Update boost to 1.71 and add asio

Readme.md

@@ -1,7 +1,7 @@
 Boost libraries - trimmed down for yuzu
 ========================================
 
-This is a subset of Boost v1.68.0 generated using the bcp tool. To get a list of boost modules guaranteed to exist, check the build script.
+This is a subset of Boost v1.71.0 generated using the bcp tool. To get a list of boost modules guaranteed to exist, check the build script.
 
 Updating this repo (on Windows)
 ===============================
@@ -20,4 +20,5 @@ To update the Boost version (or to add a new library) follow these steps:
   - `cd` to this repo's directory (`...\externals\boost\`)
   - Remove the existing boost from the repo: `rm -r boost` (This is only necessary if doing a Boost version upgrade, in case they removed any files in the new version.)
   - Run `.\build.cmd $boost_dir` to build a new trimmed down distro.
+  - Remove `libs\` and `Jamroot` if you didn't introduce any new boost dependencies that aren't header only
   - Add/remove all files in git and commit.

boost/algorithm/string/case_conv.hpp

@@ -0,0 +1,176 @@
+//  Boost string_algo library case_conv.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_CASE_CONV_HPP
+#define BOOST_STRING_CASE_CONV_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <algorithm>
+#include <locale>
+#include <boost/iterator/transform_iterator.hpp>
+
+#include <boost/range/as_literal.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/value_type.hpp>
+
+#include <boost/algorithm/string/detail/case_conv.hpp>
+
+/*! \file
+    Defines sequence case-conversion algorithms.
+    Algorithms convert each element in the input sequence to the
+    desired case using provided locales.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+//  to_lower  -----------------------------------------------//
+
+        //! Convert to lower case
+        /*!
+            Each element of the input sequence is converted to lower
+            case. The result is a copy of the input converted to lower case.
+            It is returned as a sequence or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input range
+            \param Loc A locale used for conversion
+            \return 
+                An output iterator pointing just after the last inserted character or
+                a copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+                
+        */
+        template<typename OutputIteratorT, typename RangeT>
+        inline OutputIteratorT 
+        to_lower_copy(
+            OutputIteratorT Output,
+            const RangeT& Input,
+            const std::locale& Loc=std::locale())
+        {
+            return ::boost::algorithm::detail::transform_range_copy( 
+               Output,
+               ::boost::as_literal(Input),
+               ::boost::algorithm::detail::to_lowerF<
+                    typename range_value<RangeT>::type >(Loc));
+        }
+
+        //! Convert to lower case
+        /*!
+            \overload
+        */
+        template<typename SequenceT>
+        inline SequenceT to_lower_copy( 
+            const SequenceT& Input, 
+            const std::locale& Loc=std::locale())
+        {
+            return ::boost::algorithm::detail::transform_range_copy<SequenceT>(
+                Input,
+                ::boost::algorithm::detail::to_lowerF<
+                    typename range_value<SequenceT>::type >(Loc));
+        }
+
+        //! Convert to lower case
+        /*!
+            Each element of the input sequence is converted to lower
+            case. The input sequence is modified in-place.
+
+            \param Input A range
+            \param Loc a locale used for conversion
+        */
+        template<typename WritableRangeT>
+        inline void to_lower( 
+            WritableRangeT& Input, 
+            const std::locale& Loc=std::locale())
+        {
+            ::boost::algorithm::detail::transform_range(
+                ::boost::as_literal(Input),
+                ::boost::algorithm::detail::to_lowerF<
+                    typename range_value<WritableRangeT>::type >(Loc));
+        }
+        
+//  to_upper  -----------------------------------------------//
+
+        //! Convert to upper case
+        /*!
+            Each element of the input sequence is converted to upper
+            case. The result is a copy of the input converted to upper case.
+            It is returned as a sequence or copied to the output iterator
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input range
+            \param Loc A locale used for conversion
+            \return 
+                An output iterator pointing just after the last inserted character or
+                a copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<typename OutputIteratorT, typename RangeT>
+        inline OutputIteratorT 
+        to_upper_copy(
+            OutputIteratorT Output,
+            const RangeT& Input,
+            const std::locale& Loc=std::locale())
+        {
+            return ::boost::algorithm::detail::transform_range_copy( 
+               Output,
+               ::boost::as_literal(Input),
+               ::boost::algorithm::detail::to_upperF<
+                    typename range_value<RangeT>::type >(Loc));
+        }
+
+        //! Convert to upper case
+        /*!
+            \overload
+        */
+        template<typename SequenceT>
+        inline SequenceT to_upper_copy( 
+            const SequenceT& Input, 
+            const std::locale& Loc=std::locale())
+        {
+            return ::boost::algorithm::detail::transform_range_copy<SequenceT>(
+                Input,
+                ::boost::algorithm::detail::to_upperF<
+                    typename range_value<SequenceT>::type >(Loc));
+        }
+
+        //! Convert to upper case
+        /*!
+            Each element of the input sequence is converted to upper
+            case. The input sequence is modified in-place.
+
+            \param Input An input range
+            \param Loc a locale used for conversion
+        */
+        template<typename WritableRangeT>
+        inline void to_upper( 
+            WritableRangeT& Input, 
+            const std::locale& Loc=std::locale())
+        {
+            ::boost::algorithm::detail::transform_range(
+                ::boost::as_literal(Input),
+                ::boost::algorithm::detail::to_upperF<
+                    typename range_value<WritableRangeT>::type >(Loc));
+        }
+
+    } // namespace algorithm
+
+    // pull names to the boost namespace
+    using algorithm::to_lower;
+    using algorithm::to_lower_copy;
+    using algorithm::to_upper;
+    using algorithm::to_upper_copy;
+
+} // namespace boost
+
+#endif  // BOOST_STRING_CASE_CONV_HPP

boost/algorithm/string/compare.hpp

@@ -0,0 +1,199 @@
+//  Boost string_algo library compare.hpp header file  -------------------------//
+
+//  Copyright Pavol Droba 2002-2006.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_COMPARE_HPP
+#define BOOST_STRING_COMPARE_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <locale>
+
+/*! \file
+    Defines element comparison predicates. Many algorithms in this library can
+    take an additional argument with a predicate used to compare elements.
+    This makes it possible, for instance, to have case insensitive versions
+    of the algorithms.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+        //  is_equal functor  -----------------------------------------------//
+
+        //! is_equal functor
+        /*!
+            Standard STL equal_to only handle comparison between arguments
+            of the same type. This is a less restrictive version which wraps operator ==.
+        */
+        struct is_equal
+        {
+            //! Function operator
+            /*!
+                Compare two operands for equality
+            */
+            template< typename T1, typename T2 >
+                bool operator()( const T1& Arg1, const T2& Arg2 ) const
+            {
+                return Arg1==Arg2;
+            }
+        };
+
+        //! case insensitive version of is_equal
+        /*!
+            Case insensitive comparison predicate. Comparison is done using
+            specified locales.
+        */
+        struct is_iequal
+        {
+            //! Constructor
+            /*!
+                \param Loc locales used for comparison
+            */
+            is_iequal( const std::locale& Loc=std::locale() ) :
+                m_Loc( Loc ) {}
+
+            //! Function operator
+            /*!
+                Compare two operands. Case is ignored.
+            */
+            template< typename T1, typename T2 >
+                bool operator()( const T1& Arg1, const T2& Arg2 ) const
+            {
+                #if defined(__BORLANDC__) && (__BORLANDC__ >= 0x560) && (__BORLANDC__ <= 0x564) && !defined(_USE_OLD_RW_STL)
+                    return std::toupper(Arg1)==std::toupper(Arg2);
+                #else
+                    return std::toupper<T1>(Arg1,m_Loc)==std::toupper<T2>(Arg2,m_Loc);
+                #endif
+            }
+
+        private:
+            std::locale m_Loc;
+        };
+
+        //  is_less functor  -----------------------------------------------//
+
+        //! is_less functor
+        /*!
+            Convenient version of standard std::less. Operation is templated, therefore it is 
+            not required to specify the exact types upon the construction
+         */
+        struct is_less
+        {
+            //! Functor operation
+            /*!
+                Compare two operands using > operator
+             */
+            template< typename T1, typename T2 >
+                bool operator()( const T1& Arg1, const T2& Arg2 ) const
+            {
+                return Arg1<Arg2;
+            }
+        };
+
+
+        //! case insensitive version of is_less
+        /*!
+            Case insensitive comparison predicate. Comparison is done using
+            specified locales.
+        */
+        struct is_iless
+        {
+            //! Constructor
+            /*!
+                \param Loc locales used for comparison
+            */
+            is_iless( const std::locale& Loc=std::locale() ) :
+                m_Loc( Loc ) {}
+
+            //! Function operator
+            /*!
+                Compare two operands. Case is ignored.
+            */
+            template< typename T1, typename T2 >
+                bool operator()( const T1& Arg1, const T2& Arg2 ) const
+            {
+                #if defined(__BORLANDC__) && (__BORLANDC__ >= 0x560) && (__BORLANDC__ <= 0x564) && !defined(_USE_OLD_RW_STL)
+                    return std::toupper(Arg1)<std::toupper(Arg2);
+                #else
+                    return std::toupper<T1>(Arg1,m_Loc)<std::toupper<T2>(Arg2,m_Loc);
+                #endif
+            }
+
+        private:
+            std::locale m_Loc;
+        };
+
+        //  is_not_greater functor  -----------------------------------------------//
+
+        //! is_not_greater functor
+        /*!
+            Convenient version of standard std::not_greater_to. Operation is templated, therefore it is 
+            not required to specify the exact types upon the construction
+         */
+        struct is_not_greater
+        {
+            //! Functor operation
+            /*!
+                Compare two operands using > operator
+             */
+            template< typename T1, typename T2 >
+                bool operator()( const T1& Arg1, const T2& Arg2 ) const
+            {
+                return Arg1<=Arg2;
+            }
+        };
+
+
+        //! case insensitive version of is_not_greater
+        /*!
+            Case insensitive comparison predicate. Comparison is done using
+            specified locales.
+        */
+        struct is_not_igreater
+        {
+            //! Constructor
+            /*!
+                \param Loc locales used for comparison
+            */
+            is_not_igreater( const std::locale& Loc=std::locale() ) :
+                m_Loc( Loc ) {}
+
+            //! Function operator
+            /*!
+                Compare two operands. Case is ignored.
+            */
+            template< typename T1, typename T2 >
+                bool operator()( const T1& Arg1, const T2& Arg2 ) const
+            {
+                #if defined(__BORLANDC__) && (__BORLANDC__ >= 0x560) && (__BORLANDC__ <= 0x564) && !defined(_USE_OLD_RW_STL)
+                    return std::toupper(Arg1)<=std::toupper(Arg2);
+                #else
+                    return std::toupper<T1>(Arg1,m_Loc)<=std::toupper<T2>(Arg2,m_Loc);
+                #endif
+            }
+
+        private:
+            std::locale m_Loc;
+        };
+
+
+    } // namespace algorithm
+
+    // pull names to the boost namespace
+    using algorithm::is_equal;
+    using algorithm::is_iequal;
+    using algorithm::is_less;
+    using algorithm::is_iless;
+    using algorithm::is_not_greater;
+    using algorithm::is_not_igreater;
+
+} // namespace boost
+
+
+#endif  // BOOST_STRING_COMPARE_HPP

boost/algorithm/string/concept.hpp

@@ -0,0 +1,83 @@
+//  Boost string_algo library concept.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_CONCEPT_HPP
+#define BOOST_STRING_CONCEPT_HPP
+
+#include <boost/concept_check.hpp>
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+
+/*! \file 
+    Defines concepts used in string_algo library
+*/
+
+namespace boost {
+    namespace algorithm {
+
+        //! Finder concept
+        /*!
+            Defines the Finder concept. Finder is a functor which selects
+            an arbitrary part of a string. Search is performed on
+            the range specified by starting and ending iterators.
+
+            Result of the find operation must be convertible to iterator_range.
+        */
+        template<typename FinderT, typename IteratorT>
+        struct FinderConcept
+        {
+        private:
+            typedef iterator_range<IteratorT> range;
+        public:
+            void constraints()
+            {
+                // Operation
+                r=(*pF)(i,i);
+            }
+        private:
+            range r;
+            IteratorT i;
+            FinderT* pF;    
+        }; // Finder_concept
+
+        
+        //! Formatter concept
+        /*!
+            Defines the Formatter concept. Formatter is a functor, which
+            takes a result from a finder operation and transforms it
+            in a specific way.
+
+            Result must be a container supported by container_traits, 
+            or a reference to it.
+        */
+        template<typename FormatterT, typename FinderT, typename IteratorT>
+        struct FormatterConcept
+        {
+        public:
+            void constraints()
+            {
+                // Operation
+                ::boost::begin((*pFo)( (*pF)(i,i) ));
+                ::boost::end((*pFo)( (*pF)(i,i) ));
+            }
+        private:
+            IteratorT i;
+            FinderT* pF;
+            FormatterT *pFo;
+        }; // FormatterConcept;
+
+    } // namespace algorithm
+} // namespace boost
+
+
+
+
+#endif  // BOOST_STRING_CONCEPT_HPP

boost/algorithm/string/config.hpp

@@ -0,0 +1,28 @@
+//  Boost string_algo library config.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_CONFIG_HPP
+#define BOOST_STRING_CONFIG_HPP
+
+#include <boost/config.hpp>
+#include <boost/detail/workaround.hpp>
+
+#ifdef BOOST_STRING_DEDUCED_TYPENAME
+#   error "macro already defined!"
+#endif
+
+#define BOOST_STRING_TYPENAME BOOST_DEDUCED_TYPENAME
+
+// Metrowerks workaround
+#if BOOST_WORKAROUND(__MWERKS__, <= 0x3003) // 8.x
+#pragma parse_func_templ off
+#endif
+
+#endif  // BOOST_STRING_CONFIG_HPP

boost/algorithm/string/constants.hpp

@@ -0,0 +1,36 @@
+//  Boost string_algo library constants.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_CONSTANTS_HPP
+#define BOOST_STRING_CONSTANTS_HPP
+
+namespace boost {
+    namespace algorithm {
+
+    //! Token compression mode 
+    /*!
+        Specifies token compression mode for the token_finder.
+    */
+    enum token_compress_mode_type
+    {
+        token_compress_on,    //!< Compress adjacent tokens
+        token_compress_off  //!< Do not compress adjacent tokens
+    };
+    
+    } // namespace algorithm
+
+    // pull the names to the boost namespace
+    using algorithm::token_compress_on;
+    using algorithm::token_compress_off;
+
+} // namespace boost
+
+#endif  // BOOST_STRING_CONSTANTS_HPP
+

boost/algorithm/string/detail/case_conv.hpp

@@ -0,0 +1,127 @@
+//  Boost string_algo library string_funct.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_CASE_CONV_DETAIL_HPP
+#define BOOST_STRING_CASE_CONV_DETAIL_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <locale>
+#include <functional>
+
+#include <boost/type_traits/make_unsigned.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+//  case conversion functors -----------------------------------------------//
+
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
+#pragma warning(push)
+#pragma warning(disable:4512) //assignment operator could not be generated
+#endif
+
+            // a tolower functor
+            template<typename CharT>
+            struct to_lowerF
+            {
+                typedef CharT argument_type;
+                typedef CharT result_type;
+                // Constructor
+                to_lowerF( const std::locale& Loc ) : m_Loc( &Loc ) {}
+
+                // Operation
+                CharT operator ()( CharT Ch ) const
+                {
+                    #if defined(__BORLANDC__) && (__BORLANDC__ >= 0x560) && (__BORLANDC__ <= 0x564) && !defined(_USE_OLD_RW_STL)
+                        return std::tolower( static_cast<typename boost::make_unsigned <CharT>::type> ( Ch ));
+                    #else
+                        return std::tolower<CharT>( Ch, *m_Loc );
+                    #endif
+                }
+            private:
+                const std::locale* m_Loc;
+            };
+
+            // a toupper functor
+            template<typename CharT>
+            struct to_upperF
+            {
+                typedef CharT argument_type;
+                typedef CharT result_type;
+                // Constructor
+                to_upperF( const std::locale& Loc ) : m_Loc( &Loc ) {}
+
+                // Operation
+                CharT operator ()( CharT Ch ) const
+                {
+                    #if defined(__BORLANDC__) && (__BORLANDC__ >= 0x560) && (__BORLANDC__ <= 0x564) && !defined(_USE_OLD_RW_STL)
+                        return std::toupper( static_cast<typename boost::make_unsigned <CharT>::type> ( Ch ));
+                    #else
+                        return std::toupper<CharT>( Ch, *m_Loc );
+                    #endif
+                }
+            private:
+                const std::locale* m_Loc;
+            };
+
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
+#pragma warning(pop)
+#endif
+
+// algorithm implementation -------------------------------------------------------------------------
+
+            // Transform a range
+            template<typename OutputIteratorT, typename RangeT, typename FunctorT>
+            OutputIteratorT transform_range_copy(
+                OutputIteratorT Output,
+                const RangeT& Input,
+                FunctorT Functor)
+            {
+                return std::transform( 
+                    ::boost::begin(Input), 
+                    ::boost::end(Input), 
+                    Output,
+                    Functor);
+            }
+
+            // Transform a range (in-place)
+            template<typename RangeT, typename FunctorT>
+            void transform_range(
+                const RangeT& Input,
+                FunctorT Functor)
+            {
+                std::transform( 
+                    ::boost::begin(Input), 
+                    ::boost::end(Input), 
+                    ::boost::begin(Input),
+                    Functor);
+            }
+
+            template<typename SequenceT, typename RangeT, typename FunctorT>
+            inline SequenceT transform_range_copy( 
+                const RangeT& Input, 
+                FunctorT Functor)
+            {
+                return SequenceT(
+                    ::boost::make_transform_iterator(
+                        ::boost::begin(Input),
+                        Functor),
+                    ::boost::make_transform_iterator(
+                        ::boost::end(Input), 
+                        Functor));
+            }
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+
+#endif  // BOOST_STRING_CASE_CONV_DETAIL_HPP

boost/algorithm/string/detail/find_format.hpp

@@ -0,0 +1,204 @@
+//  Boost string_algo library find_format.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+// 
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FIND_FORMAT_DETAIL_HPP
+#define BOOST_STRING_FIND_FORMAT_DETAIL_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/const_iterator.hpp>
+#include <boost/range/iterator.hpp>
+#include <boost/algorithm/string/detail/find_format_store.hpp>
+#include <boost/algorithm/string/detail/replace_storage.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+// find_format_copy (iterator variant) implementation -------------------------------//
+
+           template< 
+                typename OutputIteratorT,
+                typename InputT,
+                typename FormatterT,
+                typename FindResultT,
+                typename FormatResultT >
+            inline OutputIteratorT find_format_copy_impl2(
+                OutputIteratorT Output,
+                const InputT& Input,
+                FormatterT Formatter,
+                const FindResultT& FindResult,
+                const FormatResultT& FormatResult )
+            {       
+                typedef find_format_store<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<InputT>::type, 
+                        FormatterT,
+                        FormatResultT > store_type;
+
+                // Create store for the find result
+                store_type M( FindResult, FormatResult, Formatter );
+
+                if ( !M )
+                {
+                    // Match not found - return original sequence
+                    Output = std::copy( ::boost::begin(Input), ::boost::end(Input), Output );
+                    return Output;
+                }
+
+                // Copy the beginning of the sequence
+                Output = std::copy( ::boost::begin(Input), ::boost::begin(M), Output );
+                // Format find result
+                // Copy formatted result
+                Output = std::copy( ::boost::begin(M.format_result()), ::boost::end(M.format_result()), Output );
+                // Copy the rest of the sequence
+                Output = std::copy( M.end(), ::boost::end(Input), Output );
+
+                return Output;
+            }
+
+            template< 
+                typename OutputIteratorT,
+                typename InputT,
+                typename FormatterT,
+                typename FindResultT >
+            inline OutputIteratorT find_format_copy_impl(
+                OutputIteratorT Output,
+                const InputT& Input,
+                FormatterT Formatter,
+                const FindResultT& FindResult )
+            {   
+                if( ::boost::algorithm::detail::check_find_result(Input, FindResult) ) {
+                    return ::boost::algorithm::detail::find_format_copy_impl2( 
+                        Output,
+                        Input,
+                        Formatter,
+                        FindResult,
+                        Formatter(FindResult) );
+                } else {
+                    return std::copy( ::boost::begin(Input), ::boost::end(Input), Output );
+                }
+            }
+
+ 
+// find_format_copy implementation --------------------------------------------------//
+
+           template< 
+                typename InputT, 
+                typename FormatterT,
+                typename FindResultT,
+                typename FormatResultT >
+            inline InputT find_format_copy_impl2(
+                const InputT& Input,
+                FormatterT Formatter,
+                const FindResultT& FindResult,
+                const FormatResultT& FormatResult)
+            {
+                typedef find_format_store<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<InputT>::type, 
+                        FormatterT,
+                        FormatResultT > store_type;
+
+                // Create store for the find result
+                store_type M( FindResult, FormatResult, Formatter );
+
+                if ( !M )
+                {
+                    // Match not found - return original sequence
+                    return InputT( Input );
+                }
+
+                InputT Output;
+                // Copy the beginning of the sequence
+                boost::algorithm::detail::insert( Output, ::boost::end(Output), ::boost::begin(Input), M.begin() );
+                // Copy formatted result
+                boost::algorithm::detail::insert( Output, ::boost::end(Output), M.format_result() );
+                // Copy the rest of the sequence
+                boost::algorithm::detail::insert( Output, ::boost::end(Output), M.end(), ::boost::end(Input) );
+
+                return Output;
+            }
+
+            template< 
+                typename InputT, 
+                typename FormatterT,
+                typename FindResultT >
+            inline InputT find_format_copy_impl(
+                const InputT& Input,
+                FormatterT Formatter,
+                const FindResultT& FindResult)
+            {
+                if( ::boost::algorithm::detail::check_find_result(Input, FindResult) ) {
+                    return ::boost::algorithm::detail::find_format_copy_impl2(
+                        Input,
+                        Formatter,
+                        FindResult,
+                        Formatter(FindResult) );
+                } else {
+                    return Input;
+                }
+            }
+
+ // replace implementation ----------------------------------------------------//
+        
+            template<
+                typename InputT,
+                typename FormatterT,
+                typename FindResultT,
+                typename FormatResultT >
+            inline void find_format_impl2( 
+                InputT& Input,
+                FormatterT Formatter,
+                const FindResultT& FindResult,
+                const FormatResultT& FormatResult)
+            {
+                typedef find_format_store<
+                    BOOST_STRING_TYPENAME 
+                        range_iterator<InputT>::type, 
+                        FormatterT,
+                        FormatResultT > store_type;
+
+                // Create store for the find result
+                store_type M( FindResult, FormatResult, Formatter );
+
+                if ( !M )
+                {
+                    // Search not found - return original sequence
+                    return;
+                }
+
+                // Replace match
+                ::boost::algorithm::detail::replace( Input, M.begin(), M.end(), M.format_result() );
+            }
+
+            template<
+                typename InputT,
+                typename FormatterT,
+                typename FindResultT >
+            inline void find_format_impl( 
+                InputT& Input,
+                FormatterT Formatter,
+                const FindResultT& FindResult)
+            {
+                if( ::boost::algorithm::detail::check_find_result(Input, FindResult) ) {
+                    ::boost::algorithm::detail::find_format_impl2(
+                        Input,
+                        Formatter,
+                        FindResult,
+                        Formatter(FindResult) );
+                }
+            }
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+#endif  // BOOST_STRING_FIND_FORMAT_DETAIL_HPP

boost/algorithm/string/detail/find_format_all.hpp

@@ -0,0 +1,273 @@
+//  Boost string_algo library find_format_all.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FIND_FORMAT_ALL_DETAIL_HPP
+#define BOOST_STRING_FIND_FORMAT_ALL_DETAIL_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/const_iterator.hpp>
+#include <boost/range/value_type.hpp>
+#include <boost/algorithm/string/detail/find_format_store.hpp>
+#include <boost/algorithm/string/detail/replace_storage.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+// find_format_all_copy (iterator variant) implementation ---------------------------//
+
+           template< 
+                typename OutputIteratorT,
+                typename InputT,
+                typename FinderT,
+                typename FormatterT,
+                typename FindResultT,
+                typename FormatResultT >
+            inline OutputIteratorT find_format_all_copy_impl2(
+                OutputIteratorT Output,
+                const InputT& Input,
+                FinderT Finder,
+                FormatterT Formatter,
+                const FindResultT& FindResult,
+                const FormatResultT& FormatResult )
+            {       
+                typedef BOOST_STRING_TYPENAME 
+                    range_const_iterator<InputT>::type input_iterator_type; 
+
+                typedef find_format_store<
+                        input_iterator_type, 
+                        FormatterT,
+                        FormatResultT > store_type;
+
+                // Create store for the find result
+                store_type M( FindResult, FormatResult, Formatter );
+
+                // Initialize last match
+                input_iterator_type LastMatch=::boost::begin(Input);
+
+                // Iterate through all matches
+                while( M )
+                {
+                    // Copy the beginning of the sequence
+                    Output = std::copy( LastMatch, M.begin(), Output );
+                    // Copy formatted result
+                    Output = std::copy( ::boost::begin(M.format_result()), ::boost::end(M.format_result()), Output );
+
+                    // Proceed to the next match
+                    LastMatch=M.end();
+                    M=Finder( LastMatch, ::boost::end(Input) );
+                }
+
+                // Copy the rest of the sequence
+                Output = std::copy( LastMatch, ::boost::end(Input), Output );
+
+                return Output;
+            }
+
+            template< 
+                typename OutputIteratorT,
+                typename InputT,
+                typename FinderT,
+                typename FormatterT,
+                typename FindResultT >
+            inline OutputIteratorT find_format_all_copy_impl(
+                OutputIteratorT Output,
+                const InputT& Input,
+                FinderT Finder,
+                FormatterT Formatter,
+                const FindResultT& FindResult )
+            {   
+                if( ::boost::algorithm::detail::check_find_result(Input, FindResult) ) {
+                    return ::boost::algorithm::detail::find_format_all_copy_impl2( 
+                        Output,
+                        Input,
+                        Finder,
+                        Formatter,
+                        FindResult,
+                        Formatter(FindResult) );
+                } else {
+                    return std::copy( ::boost::begin(Input), ::boost::end(Input), Output );
+                }
+            }
+
+ // find_format_all_copy implementation ----------------------------------------------//
+
+           template< 
+                typename InputT, 
+                typename FinderT,
+                typename FormatterT,
+                typename FindResultT,
+                typename FormatResultT >
+            inline InputT find_format_all_copy_impl2(
+                const InputT& Input,
+                FinderT Finder,
+                FormatterT Formatter,
+                const FindResultT& FindResult,
+                const FormatResultT& FormatResult)
+            {
+                typedef BOOST_STRING_TYPENAME 
+                    range_const_iterator<InputT>::type input_iterator_type; 
+
+                typedef find_format_store<
+                        input_iterator_type, 
+                        FormatterT,
+                        FormatResultT > store_type;
+
+                // Create store for the find result
+                store_type M( FindResult, FormatResult, Formatter );
+
+                // Initialize last match
+                input_iterator_type LastMatch=::boost::begin(Input);
+
+                // Output temporary
+                InputT Output;
+
+                // Iterate through all matches
+                while( M )
+                {
+                    // Copy the beginning of the sequence
+                    boost::algorithm::detail::insert( Output, ::boost::end(Output), LastMatch, M.begin() );
+                    // Copy formatted result
+                    boost::algorithm::detail::insert( Output, ::boost::end(Output), M.format_result() );
+
+                    // Proceed to the next match
+                    LastMatch=M.end();
+                    M=Finder( LastMatch, ::boost::end(Input) );
+                }
+
+                // Copy the rest of the sequence
+                ::boost::algorithm::detail::insert( Output, ::boost::end(Output), LastMatch, ::boost::end(Input) );
+
+                return Output;
+            }
+
+            template< 
+                typename InputT, 
+                typename FinderT,
+                typename FormatterT,
+                typename FindResultT >
+            inline InputT find_format_all_copy_impl(
+                const InputT& Input,
+                FinderT Finder,
+                FormatterT Formatter,
+                const FindResultT& FindResult)
+            {
+                if( ::boost::algorithm::detail::check_find_result(Input, FindResult) ) {
+                    return ::boost::algorithm::detail::find_format_all_copy_impl2(
+                        Input,
+                        Finder,
+                        Formatter,
+                        FindResult,
+                        Formatter(FindResult) );
+                } else {
+                    return Input;
+                }
+            }
+
+ // find_format_all implementation ------------------------------------------------//
+        
+            template<
+                typename InputT,
+                typename FinderT,
+                typename FormatterT,
+                typename FindResultT,
+                typename FormatResultT >
+            inline void find_format_all_impl2( 
+                InputT& Input,
+                FinderT Finder,
+                FormatterT Formatter,
+                FindResultT FindResult,
+                FormatResultT FormatResult)
+            {
+                typedef BOOST_STRING_TYPENAME 
+                    range_iterator<InputT>::type input_iterator_type; 
+                typedef find_format_store<
+                        input_iterator_type, 
+                        FormatterT,
+                        FormatResultT > store_type;
+
+                // Create store for the find result
+                store_type M( FindResult, FormatResult, Formatter );
+          
+                // Instantiate replacement storage
+                std::deque<
+                    BOOST_STRING_TYPENAME range_value<InputT>::type> Storage;
+
+                // Initialize replacement iterators
+                input_iterator_type InsertIt=::boost::begin(Input);
+                input_iterator_type SearchIt=::boost::begin(Input);
+                
+                while( M )
+                {
+                    // process the segment
+                    InsertIt=process_segment( 
+                        Storage,
+                        Input,
+                        InsertIt,
+                        SearchIt,
+                        M.begin() );
+                    
+                    // Adjust search iterator
+                    SearchIt=M.end();
+
+                    // Copy formatted replace to the storage
+                    ::boost::algorithm::detail::copy_to_storage( Storage, M.format_result() );
+
+                    // Find range for a next match
+                    M=Finder( SearchIt, ::boost::end(Input) );
+                }
+
+                // process the last segment
+                InsertIt=::boost::algorithm::detail::process_segment( 
+                    Storage,
+                    Input,
+                    InsertIt,
+                    SearchIt,
+                    ::boost::end(Input) );
+                
+                if ( Storage.empty() )
+                {
+                    // Truncate input
+                    ::boost::algorithm::detail::erase( Input, InsertIt, ::boost::end(Input) );
+                }
+                else
+                {
+                    // Copy remaining data to the end of input
+                    ::boost::algorithm::detail::insert( Input, ::boost::end(Input), Storage.begin(), Storage.end() );
+                }
+            }
+
+            template<
+                typename InputT,
+                typename FinderT,
+                typename FormatterT,
+                typename FindResultT >
+            inline void find_format_all_impl( 
+                InputT& Input,
+                FinderT Finder,
+                FormatterT Formatter,
+                FindResultT FindResult)
+            {
+                if( ::boost::algorithm::detail::check_find_result(Input, FindResult) ) {
+                    ::boost::algorithm::detail::find_format_all_impl2(
+                        Input,
+                        Finder,
+                        Formatter,
+                        FindResult,
+                        Formatter(FindResult) );
+                }
+            }
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+#endif  // BOOST_STRING_FIND_FORMAT_ALL_DETAIL_HPP

boost/algorithm/string/detail/find_format_store.hpp

@@ -0,0 +1,89 @@
+//  Boost string_algo library find_format_store.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FIND_FORMAT_STORE_DETAIL_HPP
+#define BOOST_STRING_FIND_FORMAT_STORE_DETAIL_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <boost/range/iterator_range_core.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+//  temporary format and find result storage --------------------------------//
+
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
+#pragma warning(push)
+#pragma warning(disable:4512) //assignment operator could not be generated
+#endif
+            template< 
+                typename ForwardIteratorT,
+                typename FormatterT,
+                typename FormatResultT >
+            class find_format_store : 
+                public iterator_range<ForwardIteratorT>
+            {
+            public:
+                // typedefs
+                typedef iterator_range<ForwardIteratorT> base_type;
+                typedef FormatterT  formatter_type;
+                typedef FormatResultT format_result_type;
+                
+            public:
+                // Construction
+                find_format_store( 
+                        const base_type& FindResult,
+                        const format_result_type& FormatResult,
+                        const formatter_type& Formatter ) :
+                    base_type(FindResult),
+                    m_FormatResult(FormatResult),
+                    m_Formatter(Formatter) {}
+
+                // Assignment
+                template< typename FindResultT >
+                find_format_store& operator=( FindResultT FindResult )
+                {
+                    iterator_range<ForwardIteratorT>::operator=(FindResult);
+                    if( !this->empty() ) {
+                        m_FormatResult=m_Formatter(FindResult);
+                    }
+                    
+                    return *this;
+                }
+
+                // Retrieve format result
+                const format_result_type& format_result()
+                {   
+                    return m_FormatResult;
+                }
+
+            private:
+                format_result_type m_FormatResult;
+                const formatter_type& m_Formatter;
+            };
+
+            template<typename InputT, typename FindResultT>
+            bool check_find_result(InputT&, FindResultT& FindResult)
+            {
+                typedef BOOST_STRING_TYPENAME 
+                    range_const_iterator<InputT>::type input_iterator_type; 
+                iterator_range<input_iterator_type> ResultRange(FindResult);
+                return !ResultRange.empty();
+            }
+
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
+#pragma warning(pop)
+#endif
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+#endif  // BOOST_STRING_FIND_FORMAT_STORE_DETAIL_HPP

boost/algorithm/string/detail/finder.hpp

@@ -0,0 +1,639 @@
+//  Boost string_algo library finder.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2006.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FINDER_DETAIL_HPP
+#define BOOST_STRING_FINDER_DETAIL_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <boost/algorithm/string/constants.hpp>
+#include <boost/detail/iterator.hpp>
+
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/empty.hpp>
+#include <boost/range/as_literal.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+
+//  find first functor -----------------------------------------------//
+
+            // find a subsequence in the sequence ( functor )
+            /*
+                Returns a pair <begin,end> marking the subsequence in the sequence.
+                If the find fails, functor returns <End,End>
+            */
+            template<typename SearchIteratorT,typename PredicateT>
+            struct first_finderF
+            {
+                typedef SearchIteratorT search_iterator_type;
+
+                // Construction
+                template< typename SearchT >
+                first_finderF( const SearchT& Search, PredicateT Comp ) :
+                    m_Search(::boost::begin(Search), ::boost::end(Search)), m_Comp(Comp) {}
+                first_finderF(
+                        search_iterator_type SearchBegin,
+                        search_iterator_type SearchEnd,
+                        PredicateT Comp ) :
+                    m_Search(SearchBegin, SearchEnd), m_Comp(Comp) {}
+
+                // Operation
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                operator()(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) const
+                {
+                    typedef iterator_range<ForwardIteratorT> result_type;
+                    typedef ForwardIteratorT input_iterator_type;
+
+                    // Outer loop
+                    for(input_iterator_type OuterIt=Begin;
+                        OuterIt!=End;
+                        ++OuterIt)
+                    {
+                        // Sanity check
+                        if( boost::empty(m_Search) )
+                            return result_type( End, End );
+
+                        input_iterator_type InnerIt=OuterIt;
+                        search_iterator_type SubstrIt=m_Search.begin();
+                        for(;
+                            InnerIt!=End && SubstrIt!=m_Search.end();
+                            ++InnerIt,++SubstrIt)
+                        {
+                            if( !( m_Comp(*InnerIt,*SubstrIt) ) )
+                                break;
+                        }
+
+                        // Substring matching succeeded
+                        if ( SubstrIt==m_Search.end() )
+                            return result_type( OuterIt, InnerIt );
+                    }
+
+                    return result_type( End, End );
+                }
+
+            private:
+                iterator_range<search_iterator_type> m_Search;
+                PredicateT m_Comp;
+            };
+
+//  find last functor -----------------------------------------------//
+
+            // find the last match a subsequence in the sequence ( functor )
+            /*
+                Returns a pair <begin,end> marking the subsequence in the sequence.
+                If the find fails, returns <End,End>
+            */
+            template<typename SearchIteratorT, typename PredicateT>
+            struct last_finderF
+            {
+                typedef SearchIteratorT search_iterator_type;
+                typedef first_finderF<
+                    search_iterator_type,
+                    PredicateT> first_finder_type;
+
+                // Construction
+                template< typename SearchT >
+                last_finderF( const SearchT& Search, PredicateT Comp ) :
+                    m_Search(::boost::begin(Search), ::boost::end(Search)), m_Comp(Comp) {}
+                last_finderF(
+                        search_iterator_type SearchBegin,
+                        search_iterator_type SearchEnd,
+                        PredicateT Comp ) :
+                    m_Search(SearchBegin, SearchEnd), m_Comp(Comp) {}
+
+                // Operation
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                operator()(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) const
+                {
+                    typedef iterator_range<ForwardIteratorT> result_type;
+
+                    if( boost::empty(m_Search) )
+                        return result_type( End, End );
+
+                    typedef BOOST_STRING_TYPENAME boost::detail::
+                        iterator_traits<ForwardIteratorT>::iterator_category category;
+
+                    return findit( Begin, End, category() );
+                }
+
+            private:
+                // forward iterator
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                findit(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End,
+                    std::forward_iterator_tag ) const
+                {
+                    typedef iterator_range<ForwardIteratorT> result_type;
+
+                    first_finder_type first_finder(
+                        m_Search.begin(), m_Search.end(), m_Comp );
+
+                    result_type M=first_finder( Begin, End );
+                    result_type Last=M;
+
+                    while( M )
+                    {
+                        Last=M;
+                        M=first_finder( ::boost::end(M), End );
+                    }
+
+                    return Last;
+                }
+
+                // bidirectional iterator
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                findit(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End,
+                    std::bidirectional_iterator_tag ) const
+                {
+                    typedef iterator_range<ForwardIteratorT> result_type;
+                    typedef ForwardIteratorT input_iterator_type;
+
+                    // Outer loop
+                    for(input_iterator_type OuterIt=End;
+                        OuterIt!=Begin; )
+                    {
+                        input_iterator_type OuterIt2=--OuterIt;
+
+                        input_iterator_type InnerIt=OuterIt2;
+                        search_iterator_type SubstrIt=m_Search.begin();
+                        for(;
+                            InnerIt!=End && SubstrIt!=m_Search.end();
+                            ++InnerIt,++SubstrIt)
+                        {
+                            if( !( m_Comp(*InnerIt,*SubstrIt) ) )
+                                break;
+                        }
+
+                        // Substring matching succeeded
+                        if( SubstrIt==m_Search.end() )
+                            return result_type( OuterIt2, InnerIt );
+                    }
+
+                    return result_type( End, End );
+                }
+
+            private:
+                iterator_range<search_iterator_type> m_Search;
+                PredicateT m_Comp;
+            };
+
+//  find n-th functor -----------------------------------------------//
+
+            // find the n-th match of a subsequence in the sequence ( functor )
+            /*
+                Returns a pair <begin,end> marking the subsequence in the sequence.
+                If the find fails, returns <End,End>
+            */
+            template<typename SearchIteratorT, typename PredicateT>
+            struct nth_finderF
+            {
+                typedef SearchIteratorT search_iterator_type;
+                typedef first_finderF<
+                    search_iterator_type,
+                    PredicateT> first_finder_type;
+                typedef last_finderF<
+                    search_iterator_type,
+                    PredicateT> last_finder_type;
+
+                // Construction
+                template< typename SearchT >
+                nth_finderF(
+                        const SearchT& Search,
+                        int Nth,
+                        PredicateT Comp) :
+                    m_Search(::boost::begin(Search), ::boost::end(Search)),
+                    m_Nth(Nth),
+                    m_Comp(Comp) {}
+                nth_finderF(
+                        search_iterator_type SearchBegin,
+                        search_iterator_type SearchEnd,
+                        int Nth,
+                        PredicateT Comp) :
+                    m_Search(SearchBegin, SearchEnd),
+                    m_Nth(Nth),
+                    m_Comp(Comp) {}
+
+                // Operation
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                operator()(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) const
+                {
+                    if(m_Nth>=0)
+                    {
+                        return find_forward(Begin, End, m_Nth);
+                    }
+                    else
+                    {
+                        return find_backward(Begin, End, -m_Nth);
+                    }
+
+                }
+
+            private:
+                // Implementation helpers
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                find_forward(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End,
+                    unsigned int N) const
+                {
+                    typedef iterator_range<ForwardIteratorT> result_type;
+
+                    // Sanity check
+                    if( boost::empty(m_Search) )
+                        return result_type( End, End );
+
+                    // Instantiate find functor
+                    first_finder_type first_finder(
+                        m_Search.begin(), m_Search.end(), m_Comp );
+
+                    result_type M( Begin, Begin );
+
+                    for( unsigned int n=0; n<=N; ++n )
+                    {
+                        // find next match
+                        M=first_finder( ::boost::end(M), End );
+
+                        if ( !M )
+                        {
+                            // Subsequence not found, return
+                            return M;
+                        }
+                    }
+
+                    return M;
+                }
+
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                find_backward(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End,
+                    unsigned int N) const
+                {
+                    typedef iterator_range<ForwardIteratorT> result_type;
+
+                    // Sanity check
+                    if( boost::empty(m_Search) )
+                        return result_type( End, End );
+
+                    // Instantiate find functor
+                    last_finder_type last_finder(
+                        m_Search.begin(), m_Search.end(), m_Comp );
+
+                    result_type M( End, End );
+
+                    for( unsigned int n=1; n<=N; ++n )
+                    {
+                        // find next match
+                        M=last_finder( Begin, ::boost::begin(M) );
+
+                        if ( !M )
+                        {
+                            // Subsequence not found, return
+                            return M;
+                        }
+                    }
+
+                    return M;
+                }
+
+
+            private:
+                iterator_range<search_iterator_type> m_Search;
+                int m_Nth;
+                PredicateT m_Comp;
+            };
+
+//  find head/tail implementation helpers ---------------------------//
+
+            template<typename ForwardIteratorT>
+                iterator_range<ForwardIteratorT>
+            find_head_impl(
+                ForwardIteratorT Begin,
+                ForwardIteratorT End,
+                unsigned int N,
+                std::forward_iterator_tag )
+            {
+                typedef ForwardIteratorT input_iterator_type;
+                typedef iterator_range<ForwardIteratorT> result_type;
+
+                input_iterator_type It=Begin;
+                for(
+                    unsigned int Index=0;
+                    Index<N && It!=End; ++Index,++It ) {};
+
+                return result_type( Begin, It );
+            }
+
+            template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+            find_head_impl(
+                ForwardIteratorT Begin,
+                ForwardIteratorT End,
+                unsigned int N,
+                std::random_access_iterator_tag )
+            {
+                typedef iterator_range<ForwardIteratorT> result_type;
+
+                if ( (End<=Begin) || ( static_cast<unsigned int>(End-Begin) < N ) )
+                    return result_type( Begin, End );
+
+                return result_type(Begin,Begin+N);
+            }
+
+            // Find head implementation
+            template<typename ForwardIteratorT>
+                iterator_range<ForwardIteratorT>
+            find_head_impl(
+                ForwardIteratorT Begin,
+                ForwardIteratorT End,
+                unsigned int N )
+            {
+                typedef BOOST_STRING_TYPENAME boost::detail::
+                    iterator_traits<ForwardIteratorT>::iterator_category category;
+
+                return ::boost::algorithm::detail::find_head_impl( Begin, End, N, category() );
+            }
+
+            template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+            find_tail_impl(
+                ForwardIteratorT Begin,
+                ForwardIteratorT End,
+                unsigned int N,
+                std::forward_iterator_tag )
+            {
+                typedef ForwardIteratorT input_iterator_type;
+                typedef iterator_range<ForwardIteratorT> result_type;
+
+                unsigned int Index=0;
+                input_iterator_type It=Begin;
+                input_iterator_type It2=Begin;
+
+                // Advance It2 by N increments
+                for( Index=0; Index<N && It2!=End; ++Index,++It2 ) {};
+
+                // Advance It, It2 to the end
+                for(; It2!=End; ++It,++It2 ) {};
+
+                return result_type( It, It2 );
+            }
+
+            template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+            find_tail_impl(
+                ForwardIteratorT Begin,
+                ForwardIteratorT End,
+                unsigned int N,
+                std::bidirectional_iterator_tag )
+            {
+                typedef ForwardIteratorT input_iterator_type;
+                typedef iterator_range<ForwardIteratorT> result_type;
+
+                input_iterator_type It=End;
+                for(
+                    unsigned int Index=0;
+                    Index<N && It!=Begin; ++Index,--It ) {};
+
+                return result_type( It, End );
+            }
+
+            template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+            find_tail_impl(
+                ForwardIteratorT Begin,
+                ForwardIteratorT End,
+                unsigned int N,
+                std::random_access_iterator_tag )
+            {
+                typedef iterator_range<ForwardIteratorT> result_type;
+
+                if ( (End<=Begin) || ( static_cast<unsigned int>(End-Begin) < N ) )
+                    return result_type( Begin, End );
+
+                return result_type( End-N, End );
+            }
+
+                        // Operation
+            template< typename ForwardIteratorT >
+            iterator_range<ForwardIteratorT>
+            find_tail_impl(
+                ForwardIteratorT Begin,
+                ForwardIteratorT End,
+                unsigned int N )
+            {
+                typedef BOOST_STRING_TYPENAME boost::detail::
+                    iterator_traits<ForwardIteratorT>::iterator_category category;
+
+                return ::boost::algorithm::detail::find_tail_impl( Begin, End, N, category() );
+            }
+
+
+
+//  find head functor -----------------------------------------------//
+
+
+            // find a head in the sequence ( functor )
+            /*
+                This functor find a head of the specified range. For
+                a specified N, the head is a subsequence of N starting
+                elements of the range.
+            */
+            struct head_finderF
+            {
+                // Construction
+                head_finderF( int N ) : m_N(N) {}
+
+                // Operation
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                operator()(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) const
+                {
+                    if(m_N>=0)
+                    {
+                        return ::boost::algorithm::detail::find_head_impl( Begin, End, m_N );
+                    }
+                    else
+                    {
+                        iterator_range<ForwardIteratorT> Res=
+                            ::boost::algorithm::detail::find_tail_impl( Begin, End, -m_N );
+
+                        return ::boost::make_iterator_range(Begin, Res.begin());
+                    }
+                }
+
+            private:
+                int m_N;
+            };
+
+//  find tail functor -----------------------------------------------//
+
+
+            // find a tail in the sequence ( functor )
+            /*
+                This functor find a tail of the specified range. For
+                a specified N, the head is a subsequence of N starting
+                elements of the range.
+            */
+            struct tail_finderF
+            {
+                // Construction
+                tail_finderF( int N ) : m_N(N) {}
+
+                // Operation
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                operator()(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) const
+                {
+                    if(m_N>=0)
+                    {
+                        return ::boost::algorithm::detail::find_tail_impl( Begin, End, m_N );
+                    }
+                    else
+                    {
+                        iterator_range<ForwardIteratorT> Res=
+                            ::boost::algorithm::detail::find_head_impl( Begin, End, -m_N );
+
+                        return ::boost::make_iterator_range(Res.end(), End);
+                    }
+                }
+
+            private:
+                int m_N;
+            };
+
+//  find token functor -----------------------------------------------//
+
+            // find a token in a sequence ( functor )
+            /*
+                This find functor finds a token specified be a predicate
+                in a sequence. It is equivalent of std::find algorithm,
+                with an exception that it return range instead of a single
+                iterator.
+
+                If bCompress is set to true, adjacent matching tokens are
+                concatenated into one match.
+            */
+            template< typename PredicateT >
+            struct token_finderF
+            {
+                // Construction
+                token_finderF(
+                    PredicateT Pred,
+                    token_compress_mode_type eCompress=token_compress_off ) :
+                        m_Pred(Pred), m_eCompress(eCompress) {}
+
+                // Operation
+                template< typename ForwardIteratorT >
+                iterator_range<ForwardIteratorT>
+                operator()(
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) const
+                {
+                    typedef iterator_range<ForwardIteratorT> result_type;
+
+                    ForwardIteratorT It=std::find_if( Begin, End, m_Pred );
+
+                    if( It==End )
+                    {
+                        return result_type( End, End );
+                    }
+                    else
+                    {
+                        ForwardIteratorT It2=It;
+
+                        if( m_eCompress==token_compress_on )
+                        {
+                            // Find first non-matching character
+                            while( It2!=End && m_Pred(*It2) ) ++It2;
+                        }
+                        else
+                        {
+                            // Advance by one position
+                            ++It2;
+                        }
+
+                        return result_type( It, It2 );
+                    }
+                }
+
+            private:
+                PredicateT m_Pred;
+                token_compress_mode_type m_eCompress;
+            };
+
+//  find range functor -----------------------------------------------//
+
+            // find a range in the sequence ( functor )
+            /*
+                This functor actually does not perform any find operation.
+                It always returns given iterator range as a result.
+            */
+            template<typename ForwardIterator1T>
+            struct range_finderF
+            {
+                typedef ForwardIterator1T input_iterator_type;
+                typedef iterator_range<input_iterator_type> result_type;
+
+                // Construction
+                range_finderF(
+                    input_iterator_type Begin,
+                    input_iterator_type End ) : m_Range(Begin, End) {}
+
+                range_finderF(const iterator_range<input_iterator_type>& Range) :
+                    m_Range(Range) {}
+
+                // Operation
+                template< typename ForwardIterator2T >
+                iterator_range<ForwardIterator2T>
+                operator()(
+                    ForwardIterator2T,
+                    ForwardIterator2T ) const
+                {
+#if BOOST_WORKAROUND( __MWERKS__, <= 0x3003 ) 
+                    return iterator_range<const ForwardIterator2T>(this->m_Range);
+#else
+                    return m_Range;
+#endif
+                }
+
+            private:
+                iterator_range<input_iterator_type> m_Range;
+            };
+
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+#endif  // BOOST_STRING_FINDER_DETAIL_HPP

boost/algorithm/string/detail/formatter.hpp

@@ -0,0 +1,119 @@
+//  Boost string_algo library formatter.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FORMATTER_DETAIL_HPP
+#define BOOST_STRING_FORMATTER_DETAIL_HPP
+
+
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/const_iterator.hpp>
+
+#include <boost/algorithm/string/detail/util.hpp>
+
+//  generic replace functors -----------------------------------------------//
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+//  const format functor ----------------------------------------------------//
+
+            // constant format functor
+            template<typename RangeT>
+            struct const_formatF
+            {
+            private:
+                typedef BOOST_STRING_TYPENAME
+                    range_const_iterator<RangeT>::type format_iterator;
+                typedef iterator_range<format_iterator> result_type;
+            
+            public:
+                // Construction
+                const_formatF(const RangeT& Format) :
+                    m_Format(::boost::begin(Format), ::boost::end(Format)) {}
+
+                // Operation
+#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
+                template<typename Range2T>
+                result_type& operator()(const Range2T&)
+                {
+                    return m_Format;
+                }
+#endif
+
+                template<typename Range2T>
+                const result_type& operator()(const Range2T&) const
+                {
+                    return m_Format;
+                }
+
+            private:
+                result_type m_Format;
+            };
+
+//  identity format functor ----------------------------------------------------//
+
+            // identity format functor
+            template<typename RangeT>
+            struct identity_formatF
+            {
+                // Operation
+                template< typename Range2T >
+                const RangeT& operator()(const Range2T& Replace) const
+                {
+                    return RangeT(::boost::begin(Replace), ::boost::end(Replace));
+                }
+            };
+
+//  empty format functor ( used by erase ) ------------------------------------//
+        
+            // empty format functor
+            template< typename CharT >
+            struct empty_formatF
+            {
+                template< typename ReplaceT >
+                empty_container<CharT> operator()(const ReplaceT&) const
+                {
+                    return empty_container<CharT>();
+                }
+            };
+
+//  dissect format functor ----------------------------------------------------//
+
+            // dissect format functor
+            template<typename FinderT>
+            struct dissect_formatF
+            {
+            public:
+                // Construction
+                dissect_formatF(FinderT Finder) :
+                  m_Finder(Finder) {}
+
+                  // Operation
+                  template<typename RangeT>
+                  inline iterator_range< 
+                      BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type>
+                  operator()(const RangeT& Replace) const
+                  {
+                      return m_Finder(::boost::begin(Replace), ::boost::end(Replace));
+                  }
+
+            private:
+                FinderT m_Finder;
+            };
+
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+#endif  // BOOST_STRING_FORMATTER_DETAIL_HPP

boost/algorithm/string/detail/replace_storage.hpp

@@ -0,0 +1,159 @@
+//  Boost string_algo library replace_storage.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_REPLACE_STORAGE_DETAIL_HPP
+#define BOOST_STRING_REPLACE_STORAGE_DETAIL_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <algorithm>
+#include <boost/mpl/bool.hpp>
+#include <boost/algorithm/string/sequence_traits.hpp>
+#include <boost/algorithm/string/detail/sequence.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+//  storage handling routines -----------------------------------------------//
+            
+            template< typename StorageT, typename OutputIteratorT >
+            inline OutputIteratorT move_from_storage(
+                StorageT& Storage,
+                OutputIteratorT DestBegin,
+                OutputIteratorT DestEnd )
+            {
+                OutputIteratorT OutputIt=DestBegin;
+                
+                while( !Storage.empty() && OutputIt!=DestEnd )
+                {
+                    *OutputIt=Storage.front();
+                    Storage.pop_front();
+                    ++OutputIt;
+                }
+
+                return OutputIt;
+            }
+
+            template< typename StorageT, typename WhatT >
+            inline void copy_to_storage(
+                StorageT& Storage,
+                const WhatT& What )
+            {
+                Storage.insert( Storage.end(), ::boost::begin(What), ::boost::end(What) );
+            }
+
+
+//  process segment routine -----------------------------------------------//
+
+            template< bool HasStableIterators >
+            struct process_segment_helper
+            {
+                // Optimized version of process_segment for generic sequence
+                template< 
+                    typename StorageT,
+                    typename InputT,
+                    typename ForwardIteratorT >
+                ForwardIteratorT operator()(
+                    StorageT& Storage,
+                    InputT& /*Input*/,
+                    ForwardIteratorT InsertIt,
+                    ForwardIteratorT SegmentBegin,
+                    ForwardIteratorT SegmentEnd )
+                {
+                    // Copy data from the storage until the beginning of the segment
+                    ForwardIteratorT It=::boost::algorithm::detail::move_from_storage( Storage, InsertIt, SegmentBegin );
+
+                    // 3 cases are possible :
+                    //   a) Storage is empty, It==SegmentBegin
+                    //   b) Storage is empty, It!=SegmentBegin
+                    //   c) Storage is not empty
+
+                    if( Storage.empty() )
+                    {
+                        if( It==SegmentBegin )
+                        {
+                            // Case a) everything is grand, just return end of segment
+                            return SegmentEnd;
+                        }
+                        else
+                        {
+                            // Case b) move the segment backwards
+                            return std::copy( SegmentBegin, SegmentEnd, It );
+                        }
+                    }
+                    else
+                    {
+                        // Case c) -> shift the segment to the left and keep the overlap in the storage
+                        while( It!=SegmentEnd )
+                        {
+                            // Store value into storage
+                            Storage.push_back( *It );
+                            // Get the top from the storage and put it here
+                            *It=Storage.front();
+                            Storage.pop_front();
+
+                            // Advance
+                            ++It;
+                        }
+
+                        return It;
+                    }
+                }
+            };
+
+            template<>
+            struct process_segment_helper< true >
+            {
+                // Optimized version of process_segment for list-like sequence
+                template< 
+                    typename StorageT,
+                    typename InputT,
+                    typename ForwardIteratorT >
+                ForwardIteratorT operator()(
+                    StorageT& Storage,
+                    InputT& Input,
+                    ForwardIteratorT InsertIt,
+                    ForwardIteratorT SegmentBegin,
+                    ForwardIteratorT SegmentEnd )
+
+                {
+                    // Call replace to do the job
+                    ::boost::algorithm::detail::replace( Input, InsertIt, SegmentBegin, Storage );
+                    // Empty the storage
+                    Storage.clear();
+                    // Iterators were not changed, simply return the end of segment
+                    return SegmentEnd;
+                }
+            };
+
+            // Process one segment in the replace_all algorithm
+            template< 
+                typename StorageT,
+                typename InputT,
+                typename ForwardIteratorT >
+            inline ForwardIteratorT process_segment(
+                StorageT& Storage,
+                InputT& Input,
+                ForwardIteratorT InsertIt,
+                ForwardIteratorT SegmentBegin,
+                ForwardIteratorT SegmentEnd )
+            {
+                return 
+                    process_segment_helper< 
+                        has_stable_iterators<InputT>::value>()(
+                                Storage, Input, InsertIt, SegmentBegin, SegmentEnd );
+            }
+            
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+#endif  // BOOST_STRING_REPLACE_STORAGE_DETAIL_HPP

boost/algorithm/string/detail/sequence.hpp

@@ -0,0 +1,200 @@
+//  Boost string_algo library sequence.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_DETAIL_SEQUENCE_HPP
+#define BOOST_STRING_DETAIL_SEQUENCE_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <boost/mpl/bool.hpp>
+#include <boost/mpl/logical.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+
+#include <boost/algorithm/string/sequence_traits.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+//  insert helpers  -------------------------------------------------//
+        
+            template< typename InputT, typename ForwardIteratorT >
+            inline void insert(
+                InputT& Input,
+                BOOST_STRING_TYPENAME InputT::iterator At,
+                ForwardIteratorT Begin,
+                ForwardIteratorT End )
+            {
+                Input.insert( At, Begin, End );
+            }
+
+            template< typename InputT, typename InsertT >
+            inline void insert(
+                InputT& Input,
+                BOOST_STRING_TYPENAME InputT::iterator At,
+                const InsertT& Insert )
+            {
+                ::boost::algorithm::detail::insert( Input, At, ::boost::begin(Insert), ::boost::end(Insert) );
+            }
+           
+//  erase helper  ---------------------------------------------------//
+
+            // Erase a range in the sequence
+            /*
+                Returns the iterator pointing just after the erase subrange
+            */
+            template< typename InputT >
+            inline typename InputT::iterator erase(
+                InputT& Input,
+                BOOST_STRING_TYPENAME InputT::iterator From,
+                BOOST_STRING_TYPENAME InputT::iterator To )
+            {
+                return Input.erase( From, To );
+            }
+
+//  replace helper implementation  ----------------------------------//
+
+            // Optimized version of replace for generic sequence containers
+            // Assumption: insert and erase are expensive
+            template< bool HasConstTimeOperations >
+            struct replace_const_time_helper
+            {
+                template< typename InputT, typename ForwardIteratorT >
+                void operator()(
+                    InputT& Input,
+                    BOOST_STRING_TYPENAME InputT::iterator From,
+                    BOOST_STRING_TYPENAME InputT::iterator To,
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End )
+                {
+                    // Copy data to the container ( as much as possible )
+                    ForwardIteratorT InsertIt=Begin;
+                    BOOST_STRING_TYPENAME InputT::iterator InputIt=From;
+                    for(; InsertIt!=End && InputIt!=To; InsertIt++, InputIt++ )
+                    {
+                        *InputIt=*InsertIt;
+                    }
+
+                    if ( InsertIt!=End )
+                    {
+                        // Replace sequence is longer, insert it
+                        Input.insert( InputIt, InsertIt, End );
+                    }
+                    else
+                    {
+                        if ( InputIt!=To )
+                        {
+                            // Replace sequence is shorter, erase the rest
+                            Input.erase( InputIt, To );
+                        }
+                    }
+                }
+            };
+
+            template<>
+            struct replace_const_time_helper< true >
+            {
+                // Const-time erase and insert methods -> use them
+                template< typename InputT, typename ForwardIteratorT >
+                void operator()(
+                    InputT& Input,
+                    BOOST_STRING_TYPENAME InputT::iterator From,
+                    BOOST_STRING_TYPENAME InputT::iterator To,
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) 
+                {
+                    BOOST_STRING_TYPENAME InputT::iterator At=Input.erase( From, To );
+                    if ( Begin!=End )
+                    {
+                        if(!Input.empty())
+                        {
+                            Input.insert( At, Begin, End );
+                        }
+                        else
+                        {
+                            Input.insert( Input.begin(), Begin, End );
+                        }
+                    }
+                }
+            };
+
+            // No native replace method
+            template< bool HasNative >
+            struct replace_native_helper
+            {
+                template< typename InputT, typename ForwardIteratorT >
+                void operator()(
+                    InputT& Input,
+                    BOOST_STRING_TYPENAME InputT::iterator From,
+                    BOOST_STRING_TYPENAME InputT::iterator To,
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End ) 
+                {
+                    replace_const_time_helper< 
+                        boost::mpl::and_<
+                            has_const_time_insert<InputT>,
+                            has_const_time_erase<InputT> >::value >()(
+                        Input, From, To, Begin, End );
+                }
+            };
+
+            // Container has native replace method
+            template<>
+            struct replace_native_helper< true >
+            {
+                template< typename InputT, typename ForwardIteratorT >
+                void operator()(
+                    InputT& Input,
+                    BOOST_STRING_TYPENAME InputT::iterator From,
+                    BOOST_STRING_TYPENAME InputT::iterator To,
+                    ForwardIteratorT Begin,
+                    ForwardIteratorT End )
+                {
+                    Input.replace( From, To, Begin, End );
+                }
+            };
+
+//  replace helper  -------------------------------------------------//
+        
+            template< typename InputT, typename ForwardIteratorT >
+            inline void replace(
+                InputT& Input,
+                BOOST_STRING_TYPENAME InputT::iterator From,
+                BOOST_STRING_TYPENAME InputT::iterator To,
+                ForwardIteratorT Begin,
+                ForwardIteratorT End )
+            {
+                replace_native_helper< has_native_replace<InputT>::value >()(
+                    Input, From, To, Begin, End );
+            }
+
+            template< typename InputT, typename InsertT >
+            inline void replace(
+                InputT& Input,
+                BOOST_STRING_TYPENAME InputT::iterator From,
+                BOOST_STRING_TYPENAME InputT::iterator To,
+                const InsertT& Insert )
+            {
+                if(From!=To)
+                {
+                    ::boost::algorithm::detail::replace( Input, From, To, ::boost::begin(Insert), ::boost::end(Insert) );
+                }
+                else
+                {
+                    ::boost::algorithm::detail::insert( Input, From, ::boost::begin(Insert), ::boost::end(Insert) );
+                }
+            }
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+
+#endif  // BOOST_STRING_DETAIL_SEQUENCE_HPP

boost/algorithm/string/detail/util.hpp

@@ -0,0 +1,107 @@
+//  Boost string_algo library util.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_UTIL_DETAIL_HPP
+#define BOOST_STRING_UTIL_DETAIL_HPP
+
+#include <boost/algorithm/string/config.hpp>
+#include <functional>
+#include <boost/range/iterator_range_core.hpp>
+
+namespace boost {
+    namespace algorithm {
+        namespace detail {
+
+//  empty container  -----------------------------------------------//
+
+            //  empty_container 
+            /*
+                This class represents always empty container,
+                containing elements of type CharT.
+
+                It is supposed to be used in a const version only
+            */
+            template< typename CharT >
+            struct empty_container 
+            {
+                typedef empty_container<CharT> type;        
+                typedef CharT value_type;
+                typedef std::size_t size_type;
+                typedef std::ptrdiff_t difference_type;
+                typedef const value_type& reference;
+                typedef const value_type& const_reference;
+                typedef const value_type* iterator;
+                typedef const value_type* const_iterator;
+
+                
+                // Operations
+                const_iterator begin() const
+                {
+                    return reinterpret_cast<const_iterator>(0);
+                }
+
+                const_iterator end() const
+                {
+                    return reinterpret_cast<const_iterator>(0);
+                }
+
+                bool empty() const
+                {
+                    return false;
+                }
+
+                size_type size() const
+                {
+                    return 0;
+                }
+            };
+    
+//  bounded copy algorithm  -----------------------------------------------//
+
+            // Bounded version of the std::copy algorithm
+            template<typename InputIteratorT, typename OutputIteratorT>
+            inline OutputIteratorT bounded_copy(
+                InputIteratorT First, 
+                InputIteratorT Last, 
+                OutputIteratorT DestFirst,
+                OutputIteratorT DestLast )
+            {
+                InputIteratorT InputIt=First;
+                OutputIteratorT OutputIt=DestFirst;
+                for(; InputIt!=Last && OutputIt!=DestLast; InputIt++, OutputIt++ )
+                {
+                    *OutputIt=*InputIt;
+                }
+
+                return OutputIt;
+            }
+
+//  iterator range utilities -----------------------------------------//
+
+            // copy range functor
+            template< 
+                typename SeqT, 
+                typename IteratorT=BOOST_STRING_TYPENAME SeqT::const_iterator >
+            struct copy_iterator_rangeF
+            {
+                typedef iterator_range<IteratorT> argument_type;
+                typedef SeqT result_type;
+                SeqT operator()( const iterator_range<IteratorT>& Range ) const
+                {
+                    return copy_range<SeqT>(Range);
+                }
+            };
+
+        } // namespace detail
+    } // namespace algorithm
+} // namespace boost
+
+
+#endif  // BOOST_STRING_UTIL_DETAIL_HPP

boost/algorithm/string/erase.hpp

@@ -0,0 +1,844 @@
+//  Boost string_algo library erase.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2006.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_ERASE_HPP
+#define BOOST_STRING_ERASE_HPP
+
+#include <boost/algorithm/string/config.hpp>
+
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/iterator.hpp>
+#include <boost/range/const_iterator.hpp>
+
+#include <boost/algorithm/string/find_format.hpp>
+#include <boost/algorithm/string/finder.hpp>
+#include <boost/algorithm/string/formatter.hpp>
+
+/*! \file
+    Defines various erase algorithms. Each algorithm removes
+    part(s) of the input according to a searching criteria.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+//  erase_range -------------------------------------------------------//
+
+        //! Erase range algorithm
+        /*!
+            Remove the given range from the input. The result is a modified copy of 
+            the input. It is returned as a sequence or copied to the output iterator.
+    
+            \param Output An output iterator to which the result will be copied
+            \param Input An input sequence
+            \param SearchRange A range in the input to be removed
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<typename OutputIteratorT, typename RangeT>
+        inline OutputIteratorT erase_range_copy(
+            OutputIteratorT Output,
+            const RangeT& Input,
+            const iterator_range<
+                BOOST_STRING_TYPENAME 
+                    range_const_iterator<RangeT>::type>& SearchRange )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::range_finder(SearchRange),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase range algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT>
+        inline SequenceT erase_range_copy( 
+            const SequenceT& Input,
+            const iterator_range<
+                BOOST_STRING_TYPENAME 
+                    range_const_iterator<SequenceT>::type>& SearchRange )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::range_finder(SearchRange),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase range algorithm
+        /*!
+            Remove the given range from the input.
+            The input sequence is modified in-place.
+
+            \param Input An input sequence
+            \param SearchRange A range in the input to be removed
+        */
+        template<typename SequenceT>
+        inline void erase_range( 
+            SequenceT& Input,
+            const iterator_range<
+                BOOST_STRING_TYPENAME 
+                    range_iterator<SequenceT>::type>& SearchRange )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::range_finder(SearchRange),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_first  --------------------------------------------------------//
+
+        //! Erase first algorithm
+        /*!
+            Remove the first occurrence of the substring from the input.
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+            
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT erase_first_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase first algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT erase_first_copy( 
+            const SequenceT& Input,
+            const RangeT& Search )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input, 
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase first algorithm
+        /*!
+            Remove the first occurrence of the substring from the input. 
+            The input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for. 
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void erase_first( 
+            SequenceT& Input,
+            const RangeT& Search )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_first ( case insensitive ) ------------------------------------//
+
+        //! Erase first algorithm ( case insensitive )
+        /*!
+            Remove the first occurrence of the substring from the input. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT ierase_first_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase first algorithm ( case insensitive )
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT ierase_first_copy( 
+            const SequenceT& Input,
+            const RangeT& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input, 
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase first algorithm ( case insensitive )
+        /*!
+            Remove the first occurrence of the substring from the input. 
+            The input sequence is modified in-place. Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void ierase_first( 
+            SequenceT& Input,
+            const RangeT& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_last  --------------------------------------------------------//
+
+        //! Erase last algorithm
+        /*!
+            Remove the last occurrence of the substring from the input. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for.
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT erase_last_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::last_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase last algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT erase_last_copy( 
+            const SequenceT& Input,
+            const RangeT& Search )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input, 
+                ::boost::algorithm::last_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase last algorithm
+        /*!
+            Remove the last occurrence of the substring from the input. 
+            The input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void erase_last( 
+            SequenceT& Input,
+            const RangeT& Search )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::last_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_last ( case insensitive ) ------------------------------------//
+
+        //! Erase last algorithm ( case insensitive )
+        /*!
+            Remove the last occurrence of the substring from the input. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT ierase_last_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::last_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase last algorithm ( case insensitive )
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT ierase_last_copy( 
+            const SequenceT& Input,
+            const RangeT& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input, 
+                ::boost::algorithm::last_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase last algorithm ( case insensitive )
+        /*!
+            Remove the last occurrence of the substring from the input. 
+            The input sequence is modified in-place. Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void ierase_last( 
+            SequenceT& Input,
+            const RangeT& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::last_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_nth --------------------------------------------------------------------//
+
+        //! Erase nth algorithm
+        /*!
+            Remove the Nth occurrence of the substring in the input.
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT erase_nth_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            int Nth )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::nth_finder(Search, Nth),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase nth algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT erase_nth_copy( 
+            const SequenceT& Input,
+            const RangeT& Search,
+            int Nth )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input, 
+                ::boost::algorithm::nth_finder(Search, Nth),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase nth algorithm
+        /*!
+            Remove the Nth occurrence of the substring in the input.
+            The input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for. 
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void erase_nth( 
+            SequenceT& Input,
+            const RangeT& Search,
+            int Nth )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::nth_finder(Search, Nth),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_nth ( case insensitive ) ---------------------------------------------//
+
+        //! Erase nth algorithm ( case insensitive )
+        /*!
+            Remove the Nth occurrence of the substring in the input.
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator. 
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for.
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT ierase_nth_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            int Nth,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::nth_finder(Search, Nth, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase nth algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT ierase_nth_copy( 
+            const SequenceT& Input,
+            const RangeT& Search,
+            int Nth,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input, 
+                ::boost::algorithm::nth_finder(Search, Nth, is_iequal(Loc)),
+                empty_formatter(Input) );
+        }
+
+        //! Erase nth algorithm
+        /*!
+            Remove the Nth occurrence of the substring in the input.
+            The input sequence is modified in-place. Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for. 
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void ierase_nth( 
+            SequenceT& Input,
+            const RangeT& Search,
+            int Nth,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::nth_finder(Search, Nth, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+
+//  erase_all  --------------------------------------------------------//
+
+        //! Erase all algorithm
+        /*!
+            Remove all the occurrences of the string from the input. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+                        
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input sequence
+            \param Search A substring to be searched for. 
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT erase_all_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search )
+        {
+            return ::boost::algorithm::find_format_all_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase all algorithm
+        /*!
+            \overload
+        */  
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT erase_all_copy( 
+            const SequenceT& Input,
+            const RangeT& Search )
+        {
+            return ::boost::algorithm::find_format_all_copy( 
+                Input, 
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase all algorithm
+        /*!
+            Remove all the occurrences of the string from the input. 
+            The input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for. 
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void erase_all( 
+            SequenceT& Input,
+            const RangeT& Search )
+        {
+            ::boost::algorithm::find_format_all( 
+                Input, 
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_all ( case insensitive ) ------------------------------------//
+
+        //! Erase all algorithm ( case insensitive )
+        /*!
+            Remove all the occurrences of the string from the input. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator. 
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input
+
+              \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT ierase_all_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_all_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase all algorithm ( case insensitive )
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT ierase_all_copy( 
+            const SequenceT& Input,
+            const RangeT& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_all_copy( 
+                Input, 
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+        //! Erase all algorithm ( case insensitive )
+        /*!
+            Remove all the occurrences of the string from the input. 
+            The input sequence is modified in-place. Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for. 
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void ierase_all( 
+            SequenceT& Input,
+            const RangeT& Search,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format_all( 
+                Input, 
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::empty_formatter(Input) );
+        }
+
+//  erase_head --------------------------------------------------------------------//
+
+        //! Erase head algorithm
+        /*!
+            Remove the head from the input. The head is a prefix of a sequence of given size. 
+            If the sequence is shorter then required, the whole string is 
+            considered to be the head. The result is a modified copy of the input. 
+            It is returned as a sequence or copied to the output iterator.
+            
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param N Length of the head.
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename RangeT>
+        inline OutputIteratorT erase_head_copy(
+            OutputIteratorT Output,
+            const RangeT& Input,
+            int N )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::head_finder(N),
+                ::boost::algorithm::empty_formatter( Input ) );
+        }
+
+        //! Erase head algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT>
+        inline SequenceT erase_head_copy( 
+            const SequenceT& Input,
+            int N )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::head_finder(N),
+                ::boost::algorithm::empty_formatter( Input ) );
+        }
+
+        //! Erase head algorithm
+        /*!
+            Remove the head from the input. The head is a prefix of a sequence of given size. 
+            If the sequence is shorter then required, the whole string is 
+            considered to be the head. The input sequence is modified in-place.
+
+            \param Input An input string
+            \param N Length of the head
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+        */
+        template<typename SequenceT>
+        inline void erase_head( 
+            SequenceT& Input,
+            int N )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::head_finder(N),
+                ::boost::algorithm::empty_formatter( Input ) );
+        }
+
+//  erase_tail --------------------------------------------------------------------//
+
+        //! Erase tail algorithm
+        /*!
+            Remove the tail from the input. The tail is a suffix of a sequence of given size. 
+            If the sequence is shorter then required, the whole string is 
+            considered to be the tail. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param N Length of the tail.                 
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+            
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename RangeT>
+        inline OutputIteratorT erase_tail_copy(
+            OutputIteratorT Output,
+            const RangeT& Input,
+            int N )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::tail_finder(N),
+                ::boost::algorithm::empty_formatter( Input ) );
+        }
+
+        //! Erase tail algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT>
+        inline SequenceT erase_tail_copy( 
+            const SequenceT& Input,
+            int N )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::tail_finder(N),
+                ::boost::algorithm::empty_formatter( Input ) );
+        }
+
+        //! Erase tail algorithm
+        /*!
+            Remove the tail from the input. The tail is a suffix of a sequence of given size. 
+            If the sequence is shorter then required, the whole string is
+            considered to be the tail. The input sequence is modified in-place.
+
+            \param Input An input string
+            \param N Length of the tail
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+        */
+        template<typename SequenceT>
+        inline void erase_tail( 
+            SequenceT& Input,
+            int N )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::tail_finder(N),
+                ::boost::algorithm::empty_formatter( Input ) );
+        }
+
+    } // namespace algorithm
+
+    // pull names into the boost namespace
+    using algorithm::erase_range_copy;
+    using algorithm::erase_range;
+    using algorithm::erase_first_copy;
+    using algorithm::erase_first;
+    using algorithm::ierase_first_copy;
+    using algorithm::ierase_first;
+    using algorithm::erase_last_copy;
+    using algorithm::erase_last;
+    using algorithm::ierase_last_copy;
+    using algorithm::ierase_last;
+    using algorithm::erase_nth_copy;
+    using algorithm::erase_nth;
+    using algorithm::ierase_nth_copy;
+    using algorithm::ierase_nth;
+    using algorithm::erase_all_copy;
+    using algorithm::erase_all;
+    using algorithm::ierase_all_copy;
+    using algorithm::ierase_all;
+    using algorithm::erase_head_copy;
+    using algorithm::erase_head;
+    using algorithm::erase_tail_copy;
+    using algorithm::erase_tail;
+
+} // namespace boost
+
+
+#endif  // BOOST_ERASE_HPP

boost/algorithm/string/find_format.hpp

@@ -0,0 +1,287 @@
+//  Boost string_algo library find_format.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FIND_FORMAT_HPP
+#define BOOST_STRING_FIND_FORMAT_HPP
+
+#include <deque>
+#include <boost/detail/iterator.hpp>
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/const_iterator.hpp>
+#include <boost/range/as_literal.hpp>
+
+#include <boost/algorithm/string/concept.hpp>
+#include <boost/algorithm/string/detail/find_format.hpp>
+#include <boost/algorithm/string/detail/find_format_all.hpp>
+
+/*! \file
+    Defines generic replace algorithms. Each algorithm replaces
+    part(s) of the input. The part to be replaced is looked up using a Finder object.
+    Result of finding is then used by a Formatter object to generate the replacement.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+// generic replace  -----------------------------------------------------------------//
+
+        //! Generic replace algorithm
+        /*!
+            Use the Finder to search for a substring. Use the Formatter to format
+            this substring and replace it in the input.
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+    
+            \param Output An output iterator to which the result will be copied
+            \param Input An input sequence
+            \param Finder A Finder object used to search for a match to be replaced
+            \param Formatter A Formatter object used to format a match
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template< 
+            typename OutputIteratorT,
+            typename RangeT,
+            typename FinderT,
+            typename FormatterT>
+        inline OutputIteratorT find_format_copy(
+            OutputIteratorT Output,
+            const RangeT& Input,
+            FinderT Finder,
+            FormatterT Formatter )
+        {
+            // Concept check
+            BOOST_CONCEPT_ASSERT((
+                FinderConcept<
+                    FinderT,
+                    BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type>
+                ));
+            BOOST_CONCEPT_ASSERT((
+                FormatterConcept<
+                    FormatterT,
+                    FinderT,BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type>
+                ));
+
+            iterator_range<BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type> lit_input(::boost::as_literal(Input));
+
+            return detail::find_format_copy_impl(
+                Output,
+                lit_input,
+                Formatter,
+                Finder( ::boost::begin(lit_input), ::boost::end(lit_input) ) );
+        }
+
+        //! Generic replace algorithm
+        /*!
+            \overload
+        */
+        template< 
+            typename SequenceT, 
+            typename FinderT,
+            typename FormatterT>
+        inline SequenceT find_format_copy(
+            const SequenceT& Input,
+            FinderT Finder,
+            FormatterT Formatter )
+        {
+            // Concept check
+            BOOST_CONCEPT_ASSERT((
+                FinderConcept<
+                    FinderT,
+                    BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+            BOOST_CONCEPT_ASSERT((
+                FormatterConcept<
+                    FormatterT,
+                    FinderT,BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+
+            return detail::find_format_copy_impl(
+                Input,
+                Formatter,
+                Finder(::boost::begin(Input), ::boost::end(Input)));
+        }
+
+        //! Generic replace algorithm
+        /*!
+            Use the Finder to search for a substring. Use the Formatter to format
+            this substring and replace it in the input. The input is modified in-place.
+
+            \param Input An input sequence
+            \param Finder A Finder object used to search for a match to be replaced
+            \param Formatter A Formatter object used to format a match
+        */
+        template<
+            typename SequenceT,
+            typename FinderT,
+            typename FormatterT>
+        inline void find_format( 
+            SequenceT& Input,
+            FinderT Finder,
+            FormatterT Formatter)
+        {
+            // Concept check
+            BOOST_CONCEPT_ASSERT((
+                FinderConcept<
+                    FinderT,
+                    BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+            BOOST_CONCEPT_ASSERT(( 
+                FormatterConcept<
+                    FormatterT,
+                    FinderT,BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+
+            detail::find_format_impl(
+                Input,
+                Formatter,
+                Finder(::boost::begin(Input), ::boost::end(Input)));
+        }
+
+
+//  find_format_all generic ----------------------------------------------------------------//
+
+        //! Generic replace all algorithm
+        /*!
+            Use the Finder to search for a substring. Use the Formatter to format
+            this substring and replace it in the input. Repeat this for all matching
+            substrings.
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input sequence
+            \param Finder A Finder object used to search for a match to be replaced
+            \param Formatter A Formatter object used to format a match
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template< 
+            typename OutputIteratorT,
+            typename RangeT,
+            typename FinderT,
+            typename FormatterT>
+        inline OutputIteratorT find_format_all_copy(
+            OutputIteratorT Output,
+            const RangeT& Input,
+            FinderT Finder,
+            FormatterT Formatter)
+        {
+            // Concept check
+            BOOST_CONCEPT_ASSERT(( 
+                FinderConcept<
+                    FinderT,
+                    BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type>
+                ));
+            BOOST_CONCEPT_ASSERT(( 
+                FormatterConcept<
+                    FormatterT,
+                    FinderT,BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type>
+                ));
+
+            iterator_range<BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type> lit_input(::boost::as_literal(Input));
+
+            return detail::find_format_all_copy_impl(
+                Output,
+                lit_input,
+                Finder,
+                Formatter,
+                Finder(::boost::begin(lit_input), ::boost::end(lit_input)));
+        }
+
+        //! Generic replace all algorithm
+        /*!
+            \overload
+        */
+        template< 
+            typename SequenceT, 
+            typename FinderT,
+            typename FormatterT >
+        inline SequenceT find_format_all_copy(
+            const SequenceT& Input,
+            FinderT Finder,
+            FormatterT Formatter )
+        {
+            // Concept check
+            BOOST_CONCEPT_ASSERT((
+                FinderConcept<
+                    FinderT,
+                    BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+            BOOST_CONCEPT_ASSERT((
+                FormatterConcept<
+                    FormatterT,
+                    FinderT,BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+
+            return detail::find_format_all_copy_impl(
+                Input,
+                Finder,
+                Formatter,
+                Finder( ::boost::begin(Input), ::boost::end(Input) ) );
+        }
+
+        //! Generic replace all algorithm
+        /*!
+            Use the Finder to search for a substring. Use the Formatter to format
+            this substring and replace it in the input. Repeat this for all matching
+            substrings.The input is modified in-place.
+
+            \param Input An input sequence
+            \param Finder A Finder object used to search for a match to be replaced
+            \param Formatter A Formatter object used to format a match
+        */
+        template<
+            typename SequenceT,
+            typename FinderT,
+            typename FormatterT >
+        inline void find_format_all( 
+            SequenceT& Input,
+            FinderT Finder,
+            FormatterT Formatter )
+        {
+            // Concept check
+            BOOST_CONCEPT_ASSERT((
+                FinderConcept<
+                    FinderT,
+                    BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+            BOOST_CONCEPT_ASSERT((
+                FormatterConcept<
+                    FormatterT,
+                    FinderT,BOOST_STRING_TYPENAME range_const_iterator<SequenceT>::type>
+                ));
+
+            detail::find_format_all_impl(
+                Input,
+                Finder,
+                Formatter,
+                Finder(::boost::begin(Input), ::boost::end(Input)));
+
+        }
+
+    } // namespace algorithm
+
+    // pull the names to the boost namespace
+    using algorithm::find_format_copy;
+    using algorithm::find_format;
+    using algorithm::find_format_all_copy;
+    using algorithm::find_format_all;
+
+} // namespace boost
+
+
+#endif  // BOOST_STRING_FIND_FORMAT_HPP

boost/algorithm/string/finder.hpp

@@ -0,0 +1,266 @@
+//  Boost string_algo library finder.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2006.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FINDER_HPP
+#define BOOST_STRING_FINDER_HPP
+
+#include <boost/algorithm/string/config.hpp>
+
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/iterator.hpp>
+#include <boost/range/const_iterator.hpp>
+
+#include <boost/algorithm/string/constants.hpp>
+#include <boost/algorithm/string/detail/finder.hpp>
+#include <boost/algorithm/string/compare.hpp>
+
+/*! \file
+    Defines Finder generators. Finder object is a functor which is able to 
+    find a substring matching a specific criteria in the input.
+    Finders are used as a pluggable components for replace, find 
+    and split facilities. This header contains generator functions 
+    for finders provided in this library.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+//  Finder generators ------------------------------------------//
+        
+        //! "First" finder 
+        /*!
+            Construct the \c first_finder. The finder searches for the first
+            occurrence of the string in a given input.
+            The result is given as an \c iterator_range delimiting the match.
+
+            \param Search A substring to be searched for.
+            \return An instance of the \c first_finder object
+        */
+        template<typename RangeT>
+        inline detail::first_finderF<
+            BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type,
+            is_equal>
+        first_finder( const RangeT& Search )
+        {
+            return 
+                detail::first_finderF<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<RangeT>::type,
+                        is_equal>( ::boost::as_literal(Search), is_equal() ) ;
+        }
+
+        //! "First" finder
+        /*!
+            \overload
+        */
+        template<typename RangeT,typename PredicateT>
+        inline detail::first_finderF<
+            BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type,
+            PredicateT>
+        first_finder( 
+            const RangeT& Search, PredicateT Comp )
+        {
+            return 
+                detail::first_finderF<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<RangeT>::type,
+                    PredicateT>( ::boost::as_literal(Search), Comp );
+        }
+
+        //! "Last" finder
+        /*!
+            Construct the \c last_finder. The finder searches for the last
+            occurrence of the string in a given input.
+            The result is given as an \c iterator_range delimiting the match.
+
+            \param Search A substring to be searched for.
+            \return An instance of the \c last_finder object
+        */
+        template<typename RangeT>
+        inline detail::last_finderF<
+            BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type,
+            is_equal>
+        last_finder( const RangeT& Search )
+        {
+            return 
+                detail::last_finderF<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<RangeT>::type,
+                    is_equal>( ::boost::as_literal(Search), is_equal() );
+        }
+        //! "Last" finder
+        /*!
+            \overload
+        */
+        template<typename RangeT, typename PredicateT>
+        inline detail::last_finderF<
+            BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type,
+            PredicateT>
+        last_finder( const RangeT& Search, PredicateT Comp )
+        {
+            return 
+                detail::last_finderF<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<RangeT>::type,
+                    PredicateT>( ::boost::as_literal(Search), Comp ) ;
+        }
+
+        //! "Nth" finder
+        /*!
+            Construct the \c nth_finder. The finder searches for the n-th (zero-indexed)
+            occurrence of the string in a given input.
+            The result is given as an \c iterator_range delimiting the match.
+
+            \param Search A substring to be searched for.
+            \param Nth An index of the match to be find
+            \return An instance of the \c nth_finder object
+        */
+        template<typename RangeT>
+        inline detail::nth_finderF<
+            BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type,
+            is_equal>
+        nth_finder( 
+            const RangeT& Search, 
+            int Nth)
+        {
+            return 
+                detail::nth_finderF<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<RangeT>::type,
+                    is_equal>( ::boost::as_literal(Search), Nth, is_equal() ) ;
+        }
+        //! "Nth" finder
+        /*!
+            \overload
+        */
+        template<typename RangeT, typename PredicateT>
+        inline detail::nth_finderF<
+            BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type,
+            PredicateT>
+        nth_finder( 
+            const RangeT& Search, 
+            int Nth, 
+            PredicateT Comp )
+        {
+            return 
+                detail::nth_finderF<
+                    BOOST_STRING_TYPENAME 
+                        range_const_iterator<RangeT>::type,
+                    PredicateT>( ::boost::as_literal(Search), Nth, Comp );
+        }
+
+        //! "Head" finder
+        /*!
+            Construct the \c head_finder. The finder returns a head of a given
+            input. The head is a prefix of a string up to n elements in
+            size. If an input has less then n elements, whole input is 
+            considered a head.
+            The result is given as an \c iterator_range delimiting the match.
+
+            \param N The size of the head
+            \return An instance of the \c head_finder object
+        */
+        inline detail::head_finderF
+        head_finder( int N )
+        {
+            return detail::head_finderF(N);
+        }
+        
+        //! "Tail" finder
+        /*!
+            Construct the \c tail_finder. The finder returns a tail of a given
+            input. The tail is a suffix of a string up to n elements in
+            size. If an input has less then n elements, whole input is 
+            considered a head.
+            The result is given as an \c iterator_range delimiting the match.
+
+            \param N The size of the head
+            \return An instance of the \c tail_finder object
+        */
+        inline detail::tail_finderF
+        tail_finder( int N )
+        {
+            return detail::tail_finderF(N);
+        }
+
+        //! "Token" finder
+        /*!
+            Construct the \c token_finder. The finder searches for a token 
+            specified by a predicate. It is similar to std::find_if 
+            algorithm, with an exception that it return a range of
+            instead of a single iterator.
+
+            If "compress token mode" is enabled, adjacent matching tokens are 
+            concatenated into one match. Thus the finder can be used to 
+            search for continuous segments of characters satisfying the 
+            given predicate.
+
+            The result is given as an \c iterator_range delimiting the match.
+
+            \param Pred An element selection predicate
+            \param eCompress Compress flag
+            \return An instance of the \c token_finder object
+        */
+        template< typename PredicateT >
+        inline detail::token_finderF<PredicateT>
+        token_finder( 
+            PredicateT Pred, 
+            token_compress_mode_type eCompress=token_compress_off )
+        {
+            return detail::token_finderF<PredicateT>( Pred, eCompress );
+        }
+
+        //! "Range" finder
+        /*!
+            Construct the \c range_finder. The finder does not perform 
+            any operation. It simply returns the given range for 
+            any input. 
+
+            \param Begin Beginning of the range
+            \param End End of the range
+            \return An instance of the \c range_finger object
+        */
+        template< typename ForwardIteratorT >
+        inline detail::range_finderF<ForwardIteratorT>
+        range_finder(
+            ForwardIteratorT Begin,
+            ForwardIteratorT End )
+        {
+            return detail::range_finderF<ForwardIteratorT>( Begin, End );
+        }
+
+        //! "Range" finder
+        /*!       
+            \overload
+        */
+        template< typename ForwardIteratorT >
+        inline detail::range_finderF<ForwardIteratorT>
+        range_finder( iterator_range<ForwardIteratorT> Range )
+        {
+            return detail::range_finderF<ForwardIteratorT>( Range );
+        }
+
+    } // namespace algorithm
+
+    // pull the names to the boost namespace
+    using algorithm::first_finder;
+    using algorithm::last_finder;
+    using algorithm::nth_finder;
+    using algorithm::head_finder;
+    using algorithm::tail_finder;
+    using algorithm::token_finder;
+    using algorithm::range_finder;
+
+} // namespace boost
+
+
+#endif  // BOOST_STRING_FINDER_HPP

boost/algorithm/string/formatter.hpp

@@ -0,0 +1,120 @@
+//  Boost string_algo library formatter.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_FORMATTER_HPP
+#define BOOST_STRING_FORMATTER_HPP
+
+#include <boost/detail/iterator.hpp>
+#include <boost/range/value_type.hpp>
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/as_literal.hpp>
+
+#include <boost/algorithm/string/detail/formatter.hpp>
+
+/*! \file
+    Defines Formatter generators. Formatter is a functor which formats
+    a string according to given parameters. A Formatter works
+    in conjunction with a Finder. A Finder can provide additional information
+    for a specific Formatter. An example of such a cooperation is regex_finder
+    and regex_formatter.
+
+    Formatters are used as pluggable components for replace facilities. 
+    This header contains generator functions for the Formatters provided in this library.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+// generic formatters  ---------------------------------------------------------------//
+
+        //! Constant formatter
+        /*!
+            Constructs a \c const_formatter. Const formatter always returns
+            the same value, regardless of the parameter.
+
+            \param Format A predefined value used as a result for formatting
+            \return An instance of the \c const_formatter object.
+        */
+        template<typename RangeT>
+        inline detail::const_formatF<
+            iterator_range<
+                BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type> >
+        const_formatter(const RangeT& Format)
+        {
+            return detail::const_formatF<
+                iterator_range<
+                    BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type> >(::boost::as_literal(Format));
+        }
+
+        //! Identity formatter
+        /*!
+            Constructs an \c identity_formatter. Identity formatter always returns
+            the parameter.
+
+            \return An instance of the \c identity_formatter object.
+        */
+        template<typename RangeT>
+        inline detail::identity_formatF<
+            iterator_range<
+                BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type> >
+        identity_formatter()
+        {
+            return detail::identity_formatF<
+                iterator_range<
+                    BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type> >();
+        }
+
+        //! Empty formatter
+        /*!
+            Constructs an \c empty_formatter. Empty formatter always returns an empty
+            sequence. 
+
+            \param Input container used to select a correct value_type for the
+                         resulting empty_container<>.
+            \return An instance of the \c empty_formatter object.
+        */
+        template<typename RangeT>
+        inline detail::empty_formatF< 
+            BOOST_STRING_TYPENAME range_value<RangeT>::type>
+        empty_formatter(const RangeT&)
+        {
+            return detail::empty_formatF<
+                BOOST_STRING_TYPENAME range_value<RangeT>::type>();
+        }
+
+        //! Empty formatter
+        /*!
+            Constructs a \c dissect_formatter. Dissect formatter uses a specified finder
+            to extract a portion of the formatted sequence. The first finder's match is returned 
+            as a result
+
+            \param Finder a finder used to select a portion of the formatted sequence
+            \return An instance of the \c dissect_formatter object.
+        */
+        template<typename FinderT>
+        inline detail::dissect_formatF< FinderT >
+        dissect_formatter(const FinderT& Finder)
+        {
+            return detail::dissect_formatF<FinderT>(Finder);
+        }
+
+
+    } // namespace algorithm
+
+    // pull the names to the boost namespace
+    using algorithm::const_formatter;
+    using algorithm::identity_formatter;
+    using algorithm::empty_formatter;
+    using algorithm::dissect_formatter;
+
+} // namespace boost
+
+
+#endif  // BOOST_FORMATTER_HPP

boost/algorithm/string/replace.hpp

@@ -0,0 +1,926 @@
+//  Boost string_algo library replace.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2006.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_REPLACE_HPP
+#define BOOST_STRING_REPLACE_HPP
+
+#include <boost/algorithm/string/config.hpp>
+
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/iterator.hpp>
+#include <boost/range/const_iterator.hpp>
+
+#include <boost/algorithm/string/find_format.hpp>
+#include <boost/algorithm/string/finder.hpp>
+#include <boost/algorithm/string/formatter.hpp>
+#include <boost/algorithm/string/compare.hpp>
+
+/*! \file
+    Defines various replace algorithms. Each algorithm replaces
+    part(s) of the input according to set of searching and replace criteria.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+//  replace_range --------------------------------------------------------------------//
+
+        //! Replace range algorithm
+        /*!
+            Replace the given range in the input string.
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param SearchRange A range in the input to be substituted
+            \param Format A substitute string
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+              \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT replace_range_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const iterator_range<
+                BOOST_STRING_TYPENAME 
+                    range_const_iterator<Range1T>::type>& SearchRange,
+            const Range2T& Format)
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::range_finder(SearchRange),
+                ::boost::algorithm::const_formatter(Format));
+        }
+
+        //! Replace range algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT replace_range_copy( 
+            const SequenceT& Input,
+            const iterator_range<
+                BOOST_STRING_TYPENAME 
+                    range_const_iterator<SequenceT>::type>& SearchRange,
+            const RangeT& Format)
+        {
+            return ::boost::algorithm::find_format_copy(
+                Input,
+                ::boost::algorithm::range_finder(SearchRange),
+                ::boost::algorithm::const_formatter(Format));
+        }
+
+        //! Replace range algorithm
+        /*!
+            Replace the given range in the input string. 
+            The input sequence is modified in-place.
+
+            \param Input An input string
+            \param SearchRange A range in the input to be substituted
+            \param Format A substitute string
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void replace_range( 
+            SequenceT& Input,
+            const iterator_range<
+                BOOST_STRING_TYPENAME 
+                    range_iterator<SequenceT>::type>& SearchRange,
+            const RangeT& Format)
+        {
+            ::boost::algorithm::find_format(
+                Input,
+                ::boost::algorithm::range_finder(SearchRange),
+                ::boost::algorithm::const_formatter(Format));
+        }
+
+//  replace_first --------------------------------------------------------------------//
+
+        //! Replace first algorithm
+        /*!
+            Replace the first match of the search substring in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input
+
+              \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT replace_first_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const Range3T& Format)
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace first algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline SequenceT replace_first_copy( 
+            const SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace first algorithm
+        /*!
+            replace the first match of the search substring in the input 
+            with the format string. The input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void replace_first( 
+            SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+//  replace_first ( case insensitive ) ---------------------------------------------//
+
+        //! Replace first algorithm ( case insensitive )
+        /*!
+            Replace the first match of the search substring in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT ireplace_first_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const Range3T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace first algorithm ( case insensitive )
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range2T, typename Range1T>
+        inline SequenceT ireplace_first_copy( 
+            const SequenceT& Input,
+            const Range2T& Search,
+            const Range1T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace first algorithm ( case insensitive )
+        /*!
+            Replace the first match of the search substring in the input 
+            with the format string. Input sequence is modified in-place.
+            Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void ireplace_first( 
+            SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+//  replace_last --------------------------------------------------------------------//
+
+        //! Replace last algorithm
+        /*!
+            Replace the last match of the search string in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for
+            \param Format A substitute string
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input            
+
+              \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT replace_last_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const Range3T& Format )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::last_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace last algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline SequenceT replace_last_copy( 
+            const SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::last_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace last algorithm
+        /*!
+            Replace the last match of the search string in the input 
+            with the format string. Input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void replace_last( 
+            SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::last_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+//  replace_last ( case insensitive ) -----------------------------------------------//
+
+        //! Replace last algorithm ( case insensitive )
+        /*!
+            Replace the last match of the search string in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input  
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT ireplace_last_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const Range3T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::last_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace last algorithm ( case insensitive )
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline SequenceT ireplace_last_copy( 
+            const SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::last_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace last algorithm ( case insensitive )
+        /*!
+            Replace the last match of the search string in the input 
+            with the format string.The input sequence is modified in-place.
+            Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void ireplace_last( 
+            SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::last_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+//  replace_nth --------------------------------------------------------------------//
+
+        //! Replace nth algorithm
+        /*!
+            Replace an Nth (zero-indexed) match of the search string in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+            \param Format A substitute string
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT replace_nth_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            int Nth,
+            const Range3T& Format )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::nth_finder(Search, Nth),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace nth algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline SequenceT replace_nth_copy( 
+            const SequenceT& Input,
+            const Range1T& Search,
+            int Nth,
+            const Range2T& Format )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::nth_finder(Search, Nth),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace nth algorithm
+        /*!
+            Replace an Nth (zero-indexed) match of the search string in the input 
+            with the format string. Input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+            \param Format A substitute string
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void replace_nth( 
+            SequenceT& Input,
+            const Range1T& Search,
+            int Nth,
+            const Range2T& Format )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::nth_finder(Search, Nth),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+//  replace_nth ( case insensitive ) -----------------------------------------------//
+        
+        //! Replace nth algorithm ( case insensitive )
+        /*!
+            Replace an Nth (zero-indexed) match of the search string in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input            
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+       */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT ireplace_nth_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            int Nth,
+            const Range3T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::nth_finder(Search, Nth, is_iequal(Loc) ),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace nth algorithm ( case insensitive )
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline SequenceT ireplace_nth_copy( 
+            const SequenceT& Input,
+            const Range1T& Search,
+            int Nth,
+            const Range2T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::nth_finder(Search, Nth, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace nth algorithm ( case insensitive )
+        /*!
+            Replace an Nth (zero-indexed) match of the search string in the input 
+            with the format string. Input sequence is modified in-place.
+            Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Nth An index of the match to be replaced. The index is 0-based.
+                For negative N, matches are counted from the end of string.
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void ireplace_nth( 
+            SequenceT& Input,
+            const Range1T& Search,
+            int Nth,
+            const Range2T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::nth_finder(Search, Nth, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+//  replace_all --------------------------------------------------------------------//
+
+        //! Replace all algorithm
+        /*!
+            Replace all occurrences of the search string in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input 
+
+             \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT replace_all_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const Range3T& Format )
+        {
+            return ::boost::algorithm::find_format_all_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace all algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline SequenceT replace_all_copy( 
+            const SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format )
+        {
+            return ::boost::algorithm::find_format_all_copy( 
+                Input,
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace all algorithm
+        /*!
+            Replace all occurrences of the search string in the input 
+            with the format string. The input sequence is modified in-place.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void replace_all( 
+            SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format )
+        {
+            ::boost::algorithm::find_format_all( 
+                Input, 
+                ::boost::algorithm::first_finder(Search),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+        
+//  replace_all ( case insensitive ) -----------------------------------------------//
+
+        //! Replace all algorithm ( case insensitive )
+        /*!
+            Replace all occurrences of the search string in the input 
+            with the format string. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            Searching is case insensitive.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input 
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T,
+            typename Range3T>
+        inline OutputIteratorT ireplace_all_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            const Range2T& Search,
+            const Range3T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_all_copy(
+                Output,
+                Input,
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace all algorithm ( case insensitive )
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline SequenceT ireplace_all_copy( 
+            const SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            return ::boost::algorithm::find_format_all_copy( 
+                Input,
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace all algorithm ( case insensitive )
+        /*!
+            Replace all occurrences of the search string in the input 
+            with the format string.The input sequence is modified in-place.
+            Searching is case insensitive.
+
+            \param Input An input string
+            \param Search A substring to be searched for 
+            \param Format A substitute string
+            \param Loc A locale used for case insensitive comparison
+        */
+        template<typename SequenceT, typename Range1T, typename Range2T>
+        inline void ireplace_all( 
+            SequenceT& Input,
+            const Range1T& Search,
+            const Range2T& Format,
+            const std::locale& Loc=std::locale() )
+        {
+            ::boost::algorithm::find_format_all( 
+                Input, 
+                ::boost::algorithm::first_finder(Search, is_iequal(Loc)),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+        
+//  replace_head --------------------------------------------------------------------//
+
+        //! Replace head algorithm
+        /*!
+            Replace the head of the input with the given format string. 
+            The head is a prefix of a string of given size. 
+            If the sequence is shorter then required, whole string if 
+            considered to be the head. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+            
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param N Length of the head.
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+            \param Format A substitute string
+            \return An output iterator pointing just after the last inserted character or
+                a modified copy of the input  
+
+            \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT replace_head_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            int N,
+            const Range2T& Format )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::head_finder(N),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace head algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT replace_head_copy( 
+            const SequenceT& Input,
+            int N,
+            const RangeT& Format )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::head_finder(N),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace head algorithm
+        /*!
+            Replace the head of the input with the given format string. 
+            The head is a prefix of a string of given size. 
+            If the sequence is shorter then required, the whole string is 
+            considered to be the head. The input sequence is modified in-place.
+
+            \param Input An input string
+            \param N Length of the head.
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+            \param Format A substitute string
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void replace_head( 
+            SequenceT& Input,
+            int N,
+            const RangeT& Format )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::head_finder(N),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+//  replace_tail --------------------------------------------------------------------//
+
+        //! Replace tail algorithm
+        /*!
+            Replace the tail of the input with the given format string. 
+            The tail is a suffix of a string of given size. 
+            If the sequence is shorter then required, whole string is 
+            considered to be the tail. 
+            The result is a modified copy of the input. It is returned as a sequence 
+            or copied to the output iterator.
+
+            \param Output An output iterator to which the result will be copied
+            \param Input An input string
+            \param N Length of the tail.
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+            \param Format A substitute string
+            \return An output iterator pointing just after the last inserted character or
+                    a modified copy of the input   
+
+              \note The second variant of this function provides the strong exception-safety guarantee
+        */
+        template<
+            typename OutputIteratorT,
+            typename Range1T, 
+            typename Range2T>
+        inline OutputIteratorT replace_tail_copy(
+            OutputIteratorT Output,
+            const Range1T& Input,
+            int N,
+            const Range2T& Format )
+        {
+            return ::boost::algorithm::find_format_copy(
+                Output,
+                Input,
+                ::boost::algorithm::tail_finder(N),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace tail algorithm
+        /*!
+            \overload
+        */
+        template<typename SequenceT, typename RangeT>
+        inline SequenceT replace_tail_copy( 
+            const SequenceT& Input,
+            int N,
+            const RangeT& Format )
+        {
+            return ::boost::algorithm::find_format_copy( 
+                Input,
+                ::boost::algorithm::tail_finder(N),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+        //! Replace tail algorithm
+        /*!
+            Replace the tail of the input with the given format sequence. 
+            The tail is a suffix of a string of given size. 
+            If the sequence is shorter then required, the whole string is 
+            considered to be the tail. The input sequence is modified in-place.
+
+            \param Input An input string
+            \param N Length of the tail.
+                For N>=0, at most N characters are extracted.
+                For N<0, size(Input)-|N| characters are extracted.
+            \param Format A substitute string
+        */
+        template<typename SequenceT, typename RangeT>
+        inline void replace_tail( 
+            SequenceT& Input,
+            int N,
+            const RangeT& Format )
+        {
+            ::boost::algorithm::find_format( 
+                Input, 
+                ::boost::algorithm::tail_finder(N),
+                ::boost::algorithm::const_formatter(Format) );
+        }
+
+    } // namespace algorithm
+
+    // pull names to the boost namespace
+    using algorithm::replace_range_copy;
+    using algorithm::replace_range;
+    using algorithm::replace_first_copy;
+    using algorithm::replace_first;
+    using algorithm::ireplace_first_copy;
+    using algorithm::ireplace_first;
+    using algorithm::replace_last_copy;
+    using algorithm::replace_last;
+    using algorithm::ireplace_last_copy;
+    using algorithm::ireplace_last;
+    using algorithm::replace_nth_copy;
+    using algorithm::replace_nth;
+    using algorithm::ireplace_nth_copy;
+    using algorithm::ireplace_nth;
+    using algorithm::replace_all_copy;
+    using algorithm::replace_all;
+    using algorithm::ireplace_all_copy;
+    using algorithm::ireplace_all;
+    using algorithm::replace_head_copy;
+    using algorithm::replace_head;
+    using algorithm::replace_tail_copy;
+    using algorithm::replace_tail;
+
+} // namespace boost
+
+#endif  // BOOST_REPLACE_HPP

boost/algorithm/string/sequence_traits.hpp

@@ -0,0 +1,120 @@
+//  Boost string_algo library sequence_traits.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_SEQUENCE_TRAITS_HPP
+#define BOOST_STRING_SEQUENCE_TRAITS_HPP
+
+#include <boost/config.hpp>
+#include <boost/mpl/bool.hpp>
+#include <boost/algorithm/string/yes_no_type.hpp>
+
+/*! \file
+    Traits defined in this header are used by various algorithms to achieve
+    better performance for specific containers.
+    Traits provide fail-safe defaults. If a container supports some of these
+    features, it is possible to specialize the specific trait for this container.
+    For lacking compilers, it is possible of define an override for a specific tester
+    function.
+
+    Due to a language restriction, it is not currently possible to define specializations for
+    stl containers without including the corresponding header. To decrease the overhead
+    needed by this inclusion, user can selectively include a specialization
+    header for a specific container. They are located in boost/algorithm/string/stl
+    directory. Alternatively she can include boost/algorithm/string/std_collection_traits.hpp
+    header which contains specializations for all stl containers.
+*/
+
+namespace boost {
+    namespace algorithm {
+
+//  sequence traits  -----------------------------------------------//
+
+
+        //! Native replace trait
+        /*!
+            This trait specifies that the sequence has \c std::string like replace method
+        */
+        template< typename T >
+        class has_native_replace
+        {
+
+        public:
+#    if BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+            enum { value = false };
+#    else
+            BOOST_STATIC_CONSTANT(bool, value=false);
+#    endif // BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+
+
+            typedef mpl::bool_<has_native_replace<T>::value> type;
+        };
+
+
+        //! Stable iterators trait
+        /*!
+            This trait specifies that the sequence has stable iterators. It means
+            that operations like insert/erase/replace do not invalidate iterators.
+        */
+        template< typename T >
+        class has_stable_iterators
+        {
+        public:
+#    if BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+            enum { value = false };
+#    else
+            BOOST_STATIC_CONSTANT(bool, value=false);
+#    endif // BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+
+            typedef mpl::bool_<has_stable_iterators<T>::value> type;
+        };
+
+
+        //! Const time insert trait
+        /*!
+            This trait specifies that the sequence's insert method has
+            constant time complexity.
+        */
+        template< typename T >
+        class has_const_time_insert
+        {
+        public:
+#    if BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+            enum { value = false };
+#    else
+            BOOST_STATIC_CONSTANT(bool, value=false);
+#    endif // BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+
+            typedef mpl::bool_<has_const_time_insert<T>::value> type;
+        };
+
+
+        //! Const time erase trait
+        /*!
+            This trait specifies that the sequence's erase method has
+            constant time complexity.
+        */
+        template< typename T >
+        class has_const_time_erase
+        {
+        public:
+#    if BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+            enum { value = false };
+#    else
+            BOOST_STATIC_CONSTANT(bool, value=false);
+#    endif // BOOST_WORKAROUND( __IBMCPP__, <= 600 )
+
+            typedef mpl::bool_<has_const_time_erase<T>::value> type;
+        };
+
+    } // namespace algorithm
+} // namespace boost
+
+
+#endif  // BOOST_STRING_SEQUENCE_TRAITS_HPP

boost/algorithm/string/yes_no_type.hpp

@@ -0,0 +1,33 @@
+//  Boost string_algo library yes_no_type.hpp header file  ---------------------------//
+
+//  Copyright Pavol Droba 2002-2003.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/ for updates, documentation, and revision history.
+
+#ifndef BOOST_STRING_YES_NO_TYPE_DETAIL_HPP
+#define BOOST_STRING_YES_NO_TYPE_DETAIL_HPP
+
+namespace boost {
+    namespace algorithm {
+
+        // taken from boost mailing-list
+        // when yes_no_type will become officially
+        // a part of boost distribution, this header
+        // will be deprecated
+        template<int I> struct size_descriptor 
+        {
+            typedef char (& type)[I];
+        }; 
+
+        typedef size_descriptor<1>::type yes_type;
+        typedef size_descriptor<2>::type no_type;
+
+    } // namespace algorithm
+} // namespace boost
+
+
+#endif  // BOOST_STRING_YES_NO_TYPE_DETAIL_HPP

boost/array.hpp

@@ -0,0 +1,457 @@
+/* The following code declares class array,
+ * an STL container (as wrapper) for arrays of constant size.
+ *
+ * See
+ *      http://www.boost.org/libs/array/
+ * for documentation.
+ *
+ * The original author site is at: http://www.josuttis.com/
+ *
+ * (C) Copyright Nicolai M. Josuttis 2001.
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ *
+ *  9 Jan 2013 - (mtc) Added constexpr
+ * 14 Apr 2012 - (mtc) Added support for boost::hash
+ * 28 Dec 2010 - (mtc) Added cbegin and cend (and crbegin and crend) for C++Ox compatibility.
+ * 10 Mar 2010 - (mtc) fill method added, matching resolution of the standard library working group.
+ *      See <http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#776> or Trac issue #3168
+ *      Eventually, we should remove "assign" which is now a synonym for "fill" (Marshall Clow)
+ * 10 Mar 2010 - added workaround for SUNCC and !STLPort [trac #3893] (Marshall Clow)
+ * 29 Jan 2004 - c_array() added, BOOST_NO_PRIVATE_IN_AGGREGATE removed (Nico Josuttis)
+ * 23 Aug 2002 - fix for Non-MSVC compilers combined with MSVC libraries.
+ * 05 Aug 2001 - minor update (Nico Josuttis)
+ * 20 Jan 2001 - STLport fix (Beman Dawes)
+ * 29 Sep 2000 - Initial Revision (Nico Josuttis)
+ *
+ * Jan 29, 2004
+ */
+#ifndef BOOST_ARRAY_HPP
+#define BOOST_ARRAY_HPP
+
+#include <boost/detail/workaround.hpp>
+
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)  
+# pragma warning(push)  
+# pragma warning(disable:4996) // 'std::equal': Function call with parameters that may be unsafe
+# pragma warning(disable:4510) // boost::array<T,N>' : default constructor could not be generated 
+# pragma warning(disable:4610) // warning C4610: class 'boost::array<T,N>' can never be instantiated - user defined constructor required 
+#endif
+
+#include <cstddef>
+#include <stdexcept>
+#include <boost/assert.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/swap.hpp>
+
+// Handles broken standard libraries better than <iterator>
+#include <boost/detail/iterator.hpp>
+#include <boost/throw_exception.hpp>
+#include <algorithm>
+
+// FIXES for broken compilers
+#include <boost/config.hpp>
+
+
+namespace boost {
+
+    template<class T, std::size_t N>
+    class array {
+      public:
+        T elems[N];    // fixed-size array of elements of type T
+
+      public:
+        // type definitions
+        typedef T              value_type;
+        typedef T*             iterator;
+        typedef const T*       const_iterator;
+        typedef T&             reference;
+        typedef const T&       const_reference;
+        typedef std::size_t    size_type;
+        typedef std::ptrdiff_t difference_type;
+
+        // iterator support
+        iterator        begin()       { return elems; }
+        const_iterator  begin() const { return elems; }
+        const_iterator cbegin() const { return elems; }
+        
+        iterator        end()       { return elems+N; }
+        const_iterator  end() const { return elems+N; }
+        const_iterator cend() const { return elems+N; }
+
+        // reverse iterator support
+#if !defined(BOOST_MSVC_STD_ITERATOR) && !defined(BOOST_NO_STD_ITERATOR_TRAITS)
+        typedef std::reverse_iterator<iterator> reverse_iterator;
+        typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+#elif defined(_RWSTD_NO_CLASS_PARTIAL_SPEC) 
+        typedef std::reverse_iterator<iterator, std::random_access_iterator_tag, 
+              value_type, reference, iterator, difference_type> reverse_iterator; 
+        typedef std::reverse_iterator<const_iterator, std::random_access_iterator_tag,
+              value_type, const_reference, const_iterator, difference_type> const_reverse_iterator;
+#else
+        // workaround for broken reverse_iterator implementations
+        typedef std::reverse_iterator<iterator,T> reverse_iterator;
+        typedef std::reverse_iterator<const_iterator,T> const_reverse_iterator;
+#endif
+
+        reverse_iterator rbegin() { return reverse_iterator(end()); }
+        const_reverse_iterator rbegin() const {
+            return const_reverse_iterator(end());
+        }
+        const_reverse_iterator crbegin() const {
+            return const_reverse_iterator(end());
+        }
+
+        reverse_iterator rend() { return reverse_iterator(begin()); }
+        const_reverse_iterator rend() const {
+            return const_reverse_iterator(begin());
+        }
+        const_reverse_iterator crend() const {
+            return const_reverse_iterator(begin());
+        }
+
+        // operator[]
+        reference operator[](size_type i) 
+        { 
+            return BOOST_ASSERT_MSG( i < N, "out of range" ), elems[i]; 
+        }
+        
+        /*BOOST_CONSTEXPR*/ const_reference operator[](size_type i) const 
+        {     
+            return BOOST_ASSERT_MSG( i < N, "out of range" ), elems[i]; 
+        }
+
+        // at() with range check
+        reference                           at(size_type i)       { return rangecheck(i), elems[i]; }
+        /*BOOST_CONSTEXPR*/ const_reference at(size_type i) const { return rangecheck(i), elems[i]; }
+    
+        // front() and back()
+        reference front() 
+        { 
+            return elems[0]; 
+        }
+        
+        BOOST_CONSTEXPR const_reference front() const 
+        {
+            return elems[0];
+        }
+        
+        reference back() 
+        { 
+            return elems[N-1]; 
+        }
+        
+        BOOST_CONSTEXPR const_reference back() const 
+        { 
+            return elems[N-1]; 
+        }
+
+        // size is constant
+        static BOOST_CONSTEXPR size_type size() { return N; }
+        static BOOST_CONSTEXPR bool empty() { return false; }
+        static BOOST_CONSTEXPR size_type max_size() { return N; }
+        enum { static_size = N };
+
+        // swap (note: linear complexity)
+        void swap (array<T,N>& y) {
+            for (size_type i = 0; i < N; ++i)
+                boost::swap(elems[i],y.elems[i]);
+        }
+
+        // direct access to data (read-only)
+        const T* data() const { return elems; }
+        T* data() { return elems; }
+
+        // use array as C array (direct read/write access to data)
+        T* c_array() { return elems; }
+
+        // assignment with type conversion
+        template <typename T2>
+        array<T,N>& operator= (const array<T2,N>& rhs) {
+            std::copy(rhs.begin(),rhs.end(), begin());
+            return *this;
+        }
+
+        // assign one value to all elements
+        void assign (const T& value) { fill ( value ); }    // A synonym for fill
+        void fill   (const T& value)
+        {
+            std::fill_n(begin(),size(),value);
+        }
+
+        // check range (may be private because it is static)
+        static BOOST_CONSTEXPR bool rangecheck (size_type i) {
+            return i >= size() ? boost::throw_exception(std::out_of_range ("array<>: index out of range")), true : true;
+        }
+
+    };
+
+    template< class T >
+    class array< T, 0 > {
+
+      public:
+        // type definitions
+        typedef T              value_type;
+        typedef T*             iterator;
+        typedef const T*       const_iterator;
+        typedef T&             reference;
+        typedef const T&       const_reference;
+        typedef std::size_t    size_type;
+        typedef std::ptrdiff_t difference_type;
+
+        // iterator support
+        iterator        begin()       { return       iterator( reinterpret_cast<       T * >( this ) ); }
+        const_iterator  begin() const { return const_iterator( reinterpret_cast< const T * >( this ) ); }
+        const_iterator cbegin() const { return const_iterator( reinterpret_cast< const T * >( this ) ); }
+
+        iterator        end()       { return  begin(); }
+        const_iterator  end() const { return  begin(); }
+        const_iterator cend() const { return cbegin(); }
+
+        // reverse iterator support
+#if !defined(BOOST_MSVC_STD_ITERATOR) && !defined(BOOST_NO_STD_ITERATOR_TRAITS)
+        typedef std::reverse_iterator<iterator> reverse_iterator;
+        typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+#elif defined(_RWSTD_NO_CLASS_PARTIAL_SPEC) 
+        typedef std::reverse_iterator<iterator, std::random_access_iterator_tag, 
+              value_type, reference, iterator, difference_type> reverse_iterator; 
+        typedef std::reverse_iterator<const_iterator, std::random_access_iterator_tag,
+              value_type, const_reference, const_iterator, difference_type> const_reverse_iterator;
+#else
+        // workaround for broken reverse_iterator implementations
+        typedef std::reverse_iterator<iterator,T> reverse_iterator;
+        typedef std::reverse_iterator<const_iterator,T> const_reverse_iterator;
+#endif
+
+        reverse_iterator rbegin() { return reverse_iterator(end()); }
+        const_reverse_iterator rbegin() const {
+            return const_reverse_iterator(end());
+        }
+        const_reverse_iterator crbegin() const {
+            return const_reverse_iterator(end());
+        }
+
+        reverse_iterator rend() { return reverse_iterator(begin()); }
+        const_reverse_iterator rend() const {
+            return const_reverse_iterator(begin());
+        }
+        const_reverse_iterator crend() const {
+            return const_reverse_iterator(begin());
+        }
+
+        // operator[]
+        reference operator[](size_type /*i*/)
+        {
+            return failed_rangecheck();
+        }
+
+        /*BOOST_CONSTEXPR*/ const_reference operator[](size_type /*i*/) const
+        {
+            return failed_rangecheck();
+        }
+
+        // at() with range check
+        reference at(size_type /*i*/)               {   return failed_rangecheck(); }
+        /*BOOST_CONSTEXPR*/ const_reference at(size_type /*i*/) const   { return failed_rangecheck(); }
+
+        // front() and back()
+        reference front()
+        {
+            return failed_rangecheck();
+        }
+
+        BOOST_CONSTEXPR const_reference front() const
+        {
+            return failed_rangecheck();
+        }
+
+        reference back()
+        {
+            return failed_rangecheck();
+        }
+
+        BOOST_CONSTEXPR const_reference back() const
+        {
+            return failed_rangecheck();
+        }
+
+        // size is constant
+        static BOOST_CONSTEXPR size_type size() { return 0; }
+        static BOOST_CONSTEXPR bool empty() { return true; }
+        static BOOST_CONSTEXPR size_type max_size() { return 0; }
+        enum { static_size = 0 };
+
+        void swap (array<T,0>& /*y*/) {
+        }
+
+        // direct access to data (read-only)
+        const T* data() const { return 0; }
+        T* data() { return 0; }
+
+        // use array as C array (direct read/write access to data)
+        T* c_array() { return 0; }
+
+        // assignment with type conversion
+        template <typename T2>
+        array<T,0>& operator= (const array<T2,0>& ) {
+            return *this;
+        }
+
+        // assign one value to all elements
+        void assign (const T& value) { fill ( value ); }
+        void fill   (const T& ) {}
+        
+        // check range (may be private because it is static)
+        static reference failed_rangecheck () {
+                std::out_of_range e("attempt to access element of an empty array");
+                boost::throw_exception(e);
+#if defined(BOOST_NO_EXCEPTIONS) || (!defined(BOOST_MSVC) && !defined(__PATHSCALE__))
+                //
+                // We need to return something here to keep
+                // some compilers happy: however we will never
+                // actually get here....
+                //
+                static T placeholder;
+                return placeholder;
+#endif
+            }
+    };
+
+    // comparisons
+    template<class T, std::size_t N>
+    bool operator== (const array<T,N>& x, const array<T,N>& y) {
+        return std::equal(x.begin(), x.end(), y.begin());
+    }
+    template<class T, std::size_t N>
+    bool operator< (const array<T,N>& x, const array<T,N>& y) {
+        return std::lexicographical_compare(x.begin(),x.end(),y.begin(),y.end());
+    }
+    template<class T, std::size_t N>
+    bool operator!= (const array<T,N>& x, const array<T,N>& y) {
+        return !(x==y);
+    }
+    template<class T, std::size_t N>
+    bool operator> (const array<T,N>& x, const array<T,N>& y) {
+        return y<x;
+    }
+    template<class T, std::size_t N>
+    bool operator<= (const array<T,N>& x, const array<T,N>& y) {
+        return !(y<x);
+    }
+    template<class T, std::size_t N>
+    bool operator>= (const array<T,N>& x, const array<T,N>& y) {
+        return !(x<y);
+    }
+
+    // global swap()
+    template<class T, std::size_t N>
+    inline void swap (array<T,N>& x, array<T,N>& y) {
+        x.swap(y);
+    }
+
+#if defined(__SUNPRO_CC)
+//  Trac ticket #4757; the Sun Solaris compiler can't handle
+//  syntax like 'T(&get_c_array(boost::array<T,N>& arg))[N]'
+//  
+//  We can't just use this for all compilers, because the 
+//      borland compilers can't handle this form. 
+    namespace detail {
+       template <typename T, std::size_t N> struct c_array
+       {
+           typedef T type[N];
+       };
+    }
+    
+   // Specific for boost::array: simply returns its elems data member.
+   template <typename T, std::size_t N>
+   typename detail::c_array<T,N>::type& get_c_array(boost::array<T,N>& arg)
+   {
+       return arg.elems;
+   }
+
+   // Specific for boost::array: simply returns its elems data member.
+   template <typename T, std::size_t N>
+   typename detail::c_array<T,N>::type const& get_c_array(const boost::array<T,N>& arg)
+   {
+       return arg.elems;
+   }
+#else
+// Specific for boost::array: simply returns its elems data member.
+    template <typename T, std::size_t N>
+    T(&get_c_array(boost::array<T,N>& arg))[N]
+    {
+        return arg.elems;
+    }
+    
+    // Const version.
+    template <typename T, std::size_t N>
+    const T(&get_c_array(const boost::array<T,N>& arg))[N]
+    {
+        return arg.elems;
+    }
+#endif
+    
+#if 0
+    // Overload for std::array, assuming that std::array will have
+    // explicit conversion functions as discussed at the WG21 meeting
+    // in Summit, March 2009.
+    template <typename T, std::size_t N>
+    T(&get_c_array(std::array<T,N>& arg))[N]
+    {
+        return static_cast<T(&)[N]>(arg);
+    }
+    
+    // Const version.
+    template <typename T, std::size_t N>
+    const T(&get_c_array(const std::array<T,N>& arg))[N]
+    {
+        return static_cast<T(&)[N]>(arg);
+    }
+#endif
+
+    template <class It> std::size_t hash_range(It, It);
+
+    template<class T, std::size_t N>
+    std::size_t hash_value(const array<T,N>& arr)
+    {
+        return boost::hash_range(arr.begin(), arr.end());
+    }
+
+   template <size_t Idx, typename T, size_t N>
+   T &get(boost::array<T,N> &arr) BOOST_NOEXCEPT {
+       BOOST_STATIC_ASSERT_MSG ( Idx < N, "boost::get<>(boost::array &) index out of range" );
+       return arr[Idx];
+       }
+    
+   template <size_t Idx, typename T, size_t N>
+   const T &get(const boost::array<T,N> &arr) BOOST_NOEXCEPT {
+       BOOST_STATIC_ASSERT_MSG ( Idx < N, "boost::get<>(const boost::array &) index out of range" );
+       return arr[Idx];
+       }
+
+} /* namespace boost */
+
+#ifndef BOOST_NO_CXX11_HDR_ARRAY
+//  If we don't have std::array, I'm assuming that we don't have std::get
+namespace std {
+   template <size_t Idx, typename T, size_t N>
+   T &get(boost::array<T,N> &arr) BOOST_NOEXCEPT {
+       BOOST_STATIC_ASSERT_MSG ( Idx < N, "std::get<>(boost::array &) index out of range" );
+       return arr[Idx];
+       }
+    
+   template <size_t Idx, typename T, size_t N>
+   const T &get(const boost::array<T,N> &arr) BOOST_NOEXCEPT {
+       BOOST_STATIC_ASSERT_MSG ( Idx < N, "std::get<>(const boost::array &) index out of range" );
+       return arr[Idx];
+       }
+}
+#endif
+
+#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)  
+# pragma warning(pop)  
+#endif 
+
+#endif /*BOOST_ARRAY_HPP*/

boost/asio.hpp

@@ -0,0 +1,146 @@
+//
+// asio.hpp
+// ~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+//  See www.boost.org/libs/asio for documentation.
+//
+
+#ifndef BOOST_ASIO_HPP
+#define BOOST_ASIO_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/associated_allocator.hpp>
+#include <boost/asio/associated_executor.hpp>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/awaitable.hpp>
+#include <boost/asio/basic_datagram_socket.hpp>
+#include <boost/asio/basic_deadline_timer.hpp>
+#include <boost/asio/basic_io_object.hpp>
+#include <boost/asio/basic_raw_socket.hpp>
+#include <boost/asio/basic_seq_packet_socket.hpp>
+#include <boost/asio/basic_serial_port.hpp>
+#include <boost/asio/basic_signal_set.hpp>
+#include <boost/asio/basic_socket.hpp>
+#include <boost/asio/basic_socket_acceptor.hpp>
+#include <boost/asio/basic_socket_iostream.hpp>
+#include <boost/asio/basic_socket_streambuf.hpp>
+#include <boost/asio/basic_stream_socket.hpp>
+#include <boost/asio/basic_streambuf.hpp>
+#include <boost/asio/basic_waitable_timer.hpp>
+#include <boost/asio/bind_executor.hpp>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/buffered_read_stream_fwd.hpp>
+#include <boost/asio/buffered_read_stream.hpp>
+#include <boost/asio/buffered_stream_fwd.hpp>
+#include <boost/asio/buffered_stream.hpp>
+#include <boost/asio/buffered_write_stream_fwd.hpp>
+#include <boost/asio/buffered_write_stream.hpp>
+#include <boost/asio/buffers_iterator.hpp>
+#include <boost/asio/co_spawn.hpp>
+#include <boost/asio/completion_condition.hpp>
+#include <boost/asio/compose.hpp>
+#include <boost/asio/connect.hpp>
+#include <boost/asio/coroutine.hpp>
+#include <boost/asio/deadline_timer.hpp>
+#include <boost/asio/defer.hpp>
+#include <boost/asio/detached.hpp>
+#include <boost/asio/dispatch.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/executor.hpp>
+#include <boost/asio/executor_work_guard.hpp>
+#include <boost/asio/generic/basic_endpoint.hpp>
+#include <boost/asio/generic/datagram_protocol.hpp>
+#include <boost/asio/generic/raw_protocol.hpp>
+#include <boost/asio/generic/seq_packet_protocol.hpp>
+#include <boost/asio/generic/stream_protocol.hpp>
+#include <boost/asio/handler_alloc_hook.hpp>
+#include <boost/asio/handler_continuation_hook.hpp>
+#include <boost/asio/handler_invoke_hook.hpp>
+#include <boost/asio/high_resolution_timer.hpp>
+#include <boost/asio/io_context.hpp>
+#include <boost/asio/io_context_strand.hpp>
+#include <boost/asio/io_service.hpp>
+#include <boost/asio/io_service_strand.hpp>
+#include <boost/asio/ip/address.hpp>
+#include <boost/asio/ip/address_v4.hpp>
+#include <boost/asio/ip/address_v4_iterator.hpp>
+#include <boost/asio/ip/address_v4_range.hpp>
+#include <boost/asio/ip/address_v6.hpp>
+#include <boost/asio/ip/address_v6_iterator.hpp>
+#include <boost/asio/ip/address_v6_range.hpp>
+#include <boost/asio/ip/network_v4.hpp>
+#include <boost/asio/ip/network_v6.hpp>
+#include <boost/asio/ip/bad_address_cast.hpp>
+#include <boost/asio/ip/basic_endpoint.hpp>
+#include <boost/asio/ip/basic_resolver.hpp>
+#include <boost/asio/ip/basic_resolver_entry.hpp>
+#include <boost/asio/ip/basic_resolver_iterator.hpp>
+#include <boost/asio/ip/basic_resolver_query.hpp>
+#include <boost/asio/ip/host_name.hpp>
+#include <boost/asio/ip/icmp.hpp>
+#include <boost/asio/ip/multicast.hpp>
+#include <boost/asio/ip/resolver_base.hpp>
+#include <boost/asio/ip/resolver_query_base.hpp>
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/asio/ip/udp.hpp>
+#include <boost/asio/ip/unicast.hpp>
+#include <boost/asio/ip/v6_only.hpp>
+#include <boost/asio/is_executor.hpp>
+#include <boost/asio/is_read_buffered.hpp>
+#include <boost/asio/is_write_buffered.hpp>
+#include <boost/asio/local/basic_endpoint.hpp>
+#include <boost/asio/local/connect_pair.hpp>
+#include <boost/asio/local/datagram_protocol.hpp>
+#include <boost/asio/local/stream_protocol.hpp>
+#include <boost/asio/packaged_task.hpp>
+#include <boost/asio/placeholders.hpp>
+#include <boost/asio/posix/basic_descriptor.hpp>
+#include <boost/asio/posix/basic_stream_descriptor.hpp>
+#include <boost/asio/posix/descriptor.hpp>
+#include <boost/asio/posix/descriptor_base.hpp>
+#include <boost/asio/posix/stream_descriptor.hpp>
+#include <boost/asio/post.hpp>
+#include <boost/asio/read.hpp>
+#include <boost/asio/read_at.hpp>
+#include <boost/asio/read_until.hpp>
+#include <boost/asio/redirect_error.hpp>
+#include <boost/asio/serial_port.hpp>
+#include <boost/asio/serial_port_base.hpp>
+#include <boost/asio/signal_set.hpp>
+#include <boost/asio/socket_base.hpp>
+#include <boost/asio/steady_timer.hpp>
+#include <boost/asio/strand.hpp>
+#include <boost/asio/streambuf.hpp>
+#include <boost/asio/system_context.hpp>
+#include <boost/asio/system_executor.hpp>
+#include <boost/asio/system_timer.hpp>
+#include <boost/asio/this_coro.hpp>
+#include <boost/asio/thread_pool.hpp>
+#include <boost/asio/time_traits.hpp>
+#include <boost/asio/use_awaitable.hpp>
+#include <boost/asio/use_future.hpp>
+#include <boost/asio/uses_executor.hpp>
+#include <boost/asio/version.hpp>
+#include <boost/asio/wait_traits.hpp>
+#include <boost/asio/windows/basic_object_handle.hpp>
+#include <boost/asio/windows/basic_overlapped_handle.hpp>
+#include <boost/asio/windows/basic_random_access_handle.hpp>
+#include <boost/asio/windows/basic_stream_handle.hpp>
+#include <boost/asio/windows/object_handle.hpp>
+#include <boost/asio/windows/overlapped_handle.hpp>
+#include <boost/asio/windows/overlapped_ptr.hpp>
+#include <boost/asio/windows/random_access_handle.hpp>
+#include <boost/asio/windows/stream_handle.hpp>
+#include <boost/asio/write.hpp>
+#include <boost/asio/write_at.hpp>
+
+#endif // BOOST_ASIO_HPP

boost/asio/associated_allocator.hpp

@@ -0,0 +1,133 @@
+//
+// associated_allocator.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_ASSOCIATED_ALLOCATOR_HPP
+#define BOOST_ASIO_ASSOCIATED_ALLOCATOR_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <memory>
+#include <boost/asio/detail/type_traits.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename>
+struct associated_allocator_check
+{
+  typedef void type;
+};
+
+template <typename T, typename E, typename = void>
+struct associated_allocator_impl
+{
+  typedef E type;
+
+  static type get(const T&, const E& e) BOOST_ASIO_NOEXCEPT
+  {
+    return e;
+  }
+};
+
+template <typename T, typename E>
+struct associated_allocator_impl<T, E,
+  typename associated_allocator_check<typename T::allocator_type>::type>
+{
+  typedef typename T::allocator_type type;
+
+  static type get(const T& t, const E&) BOOST_ASIO_NOEXCEPT
+  {
+    return t.get_allocator();
+  }
+};
+
+} // namespace detail
+
+/// Traits type used to obtain the allocator associated with an object.
+/**
+ * A program may specialise this traits type if the @c T template parameter in
+ * the specialisation is a user-defined type. The template parameter @c
+ * Allocator shall be a type meeting the Allocator requirements.
+ *
+ * Specialisations shall meet the following requirements, where @c t is a const
+ * reference to an object of type @c T, and @c a is an object of type @c
+ * Allocator.
+ *
+ * @li Provide a nested typedef @c type that identifies a type meeting the
+ * Allocator requirements.
+ *
+ * @li Provide a noexcept static member function named @c get, callable as @c
+ * get(t) and with return type @c type.
+ *
+ * @li Provide a noexcept static member function named @c get, callable as @c
+ * get(t,a) and with return type @c type.
+ */
+template <typename T, typename Allocator = std::allocator<void> >
+struct associated_allocator
+{
+  /// If @c T has a nested type @c allocator_type, <tt>T::allocator_type</tt>.
+  /// Otherwise @c Allocator.
+#if defined(GENERATING_DOCUMENTATION)
+  typedef see_below type;
+#else // defined(GENERATING_DOCUMENTATION)
+  typedef typename detail::associated_allocator_impl<T, Allocator>::type type;
+#endif // defined(GENERATING_DOCUMENTATION)
+
+  /// If @c T has a nested type @c allocator_type, returns
+  /// <tt>t.get_allocator()</tt>. Otherwise returns @c a.
+  static type get(const T& t,
+      const Allocator& a = Allocator()) BOOST_ASIO_NOEXCEPT
+  {
+    return detail::associated_allocator_impl<T, Allocator>::get(t, a);
+  }
+};
+
+/// Helper function to obtain an object's associated allocator.
+/**
+ * @returns <tt>associated_allocator<T>::get(t)</tt>
+ */
+template <typename T>
+inline typename associated_allocator<T>::type
+get_associated_allocator(const T& t) BOOST_ASIO_NOEXCEPT
+{
+  return associated_allocator<T>::get(t);
+}
+
+/// Helper function to obtain an object's associated allocator.
+/**
+ * @returns <tt>associated_allocator<T, Allocator>::get(t, a)</tt>
+ */
+template <typename T, typename Allocator>
+inline typename associated_allocator<T, Allocator>::type
+get_associated_allocator(const T& t, const Allocator& a) BOOST_ASIO_NOEXCEPT
+{
+  return associated_allocator<T, Allocator>::get(t, a);
+}
+
+#if defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
+
+template <typename T, typename Allocator = std::allocator<void> >
+using associated_allocator_t
+  = typename associated_allocator<T, Allocator>::type;
+
+#endif // defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_ASSOCIATED_ALLOCATOR_HPP

boost/asio/associated_executor.hpp

@@ -0,0 +1,151 @@
+//
+// associated_executor.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_ASSOCIATED_EXECUTOR_HPP
+#define BOOST_ASIO_ASSOCIATED_EXECUTOR_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/is_executor.hpp>
+#include <boost/asio/system_executor.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename>
+struct associated_executor_check
+{
+  typedef void type;
+};
+
+template <typename T, typename E, typename = void>
+struct associated_executor_impl
+{
+  typedef E type;
+
+  static type get(const T&, const E& e) BOOST_ASIO_NOEXCEPT
+  {
+    return e;
+  }
+};
+
+template <typename T, typename E>
+struct associated_executor_impl<T, E,
+  typename associated_executor_check<typename T::executor_type>::type>
+{
+  typedef typename T::executor_type type;
+
+  static type get(const T& t, const E&) BOOST_ASIO_NOEXCEPT
+  {
+    return t.get_executor();
+  }
+};
+
+} // namespace detail
+
+/// Traits type used to obtain the executor associated with an object.
+/**
+ * A program may specialise this traits type if the @c T template parameter in
+ * the specialisation is a user-defined type. The template parameter @c
+ * Executor shall be a type meeting the Executor requirements.
+ *
+ * Specialisations shall meet the following requirements, where @c t is a const
+ * reference to an object of type @c T, and @c e is an object of type @c
+ * Executor.
+ *
+ * @li Provide a nested typedef @c type that identifies a type meeting the
+ * Executor requirements.
+ *
+ * @li Provide a noexcept static member function named @c get, callable as @c
+ * get(t) and with return type @c type.
+ *
+ * @li Provide a noexcept static member function named @c get, callable as @c
+ * get(t,e) and with return type @c type.
+ */
+template <typename T, typename Executor = system_executor>
+struct associated_executor
+{
+  /// If @c T has a nested type @c executor_type, <tt>T::executor_type</tt>.
+  /// Otherwise @c Executor.
+#if defined(GENERATING_DOCUMENTATION)
+  typedef see_below type;
+#else // defined(GENERATING_DOCUMENTATION)
+  typedef typename detail::associated_executor_impl<T, Executor>::type type;
+#endif // defined(GENERATING_DOCUMENTATION)
+
+  /// If @c T has a nested type @c executor_type, returns
+  /// <tt>t.get_executor()</tt>. Otherwise returns @c ex.
+  static type get(const T& t,
+      const Executor& ex = Executor()) BOOST_ASIO_NOEXCEPT
+  {
+    return detail::associated_executor_impl<T, Executor>::get(t, ex);
+  }
+};
+
+/// Helper function to obtain an object's associated executor.
+/**
+ * @returns <tt>associated_executor<T>::get(t)</tt>
+ */
+template <typename T>
+inline typename associated_executor<T>::type
+get_associated_executor(const T& t) BOOST_ASIO_NOEXCEPT
+{
+  return associated_executor<T>::get(t);
+}
+
+/// Helper function to obtain an object's associated executor.
+/**
+ * @returns <tt>associated_executor<T, Executor>::get(t, ex)</tt>
+ */
+template <typename T, typename Executor>
+inline typename associated_executor<T, Executor>::type
+get_associated_executor(const T& t, const Executor& ex,
+    typename enable_if<is_executor<
+      Executor>::value>::type* = 0) BOOST_ASIO_NOEXCEPT
+{
+  return associated_executor<T, Executor>::get(t, ex);
+}
+
+/// Helper function to obtain an object's associated executor.
+/**
+ * @returns <tt>associated_executor<T, typename
+ * ExecutionContext::executor_type>::get(t, ctx.get_executor())</tt>
+ */
+template <typename T, typename ExecutionContext>
+inline typename associated_executor<T,
+  typename ExecutionContext::executor_type>::type
+get_associated_executor(const T& t, ExecutionContext& ctx,
+    typename enable_if<is_convertible<ExecutionContext&,
+      execution_context&>::value>::type* = 0) BOOST_ASIO_NOEXCEPT
+{
+  return associated_executor<T,
+    typename ExecutionContext::executor_type>::get(t, ctx.get_executor());
+}
+
+#if defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
+
+template <typename T, typename Executor = system_executor>
+using associated_executor_t = typename associated_executor<T, Executor>::type;
+
+#endif // defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_ASSOCIATED_EXECUTOR_HPP

boost/asio/async_result.hpp

@@ -0,0 +1,358 @@
+//
+// async_result.hpp
+// ~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_ASYNC_RESULT_HPP
+#define BOOST_ASIO_ASYNC_RESULT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/detail/variadic_templates.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// An interface for customising the behaviour of an initiating function.
+/**
+ * The async_result traits class is used for determining:
+ *
+ * @li the concrete completion handler type to be called at the end of the
+ * asynchronous operation;
+ *
+ * @li the initiating function return type; and
+ *
+ * @li how the return value of the initiating function is obtained.
+ *
+ * The trait allows the handler and return types to be determined at the point
+ * where the specific completion handler signature is known.
+ *
+ * This template may be specialised for user-defined completion token types.
+ * The primary template assumes that the CompletionToken is the completion
+ * handler.
+ */
+template <typename CompletionToken, typename Signature>
+class async_result
+{
+public:
+  /// The concrete completion handler type for the specific signature.
+  typedef CompletionToken completion_handler_type;
+
+  /// The return type of the initiating function.
+  typedef void return_type;
+
+  /// Construct an async result from a given handler.
+  /**
+   * When using a specalised async_result, the constructor has an opportunity
+   * to initialise some state associated with the completion handler, which is
+   * then returned from the initiating function.
+   */
+  explicit async_result(completion_handler_type& h)
+  {
+    (void)h;
+  }
+
+  /// Obtain the value to be returned from the initiating function.
+  return_type get()
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES) \
+  || defined(GENERATING_DOCUMENTATION)
+
+  /// Initiate the asynchronous operation that will produce the result, and
+  /// obtain the value to be returned from the initiating function.
+  template <typename Initiation, typename RawCompletionToken, typename... Args>
+  static return_type initiate(
+      BOOST_ASIO_MOVE_ARG(Initiation) initiation,
+      BOOST_ASIO_MOVE_ARG(RawCompletionToken) token,
+      BOOST_ASIO_MOVE_ARG(Args)... args)
+  {
+    BOOST_ASIO_MOVE_CAST(Initiation)(initiation)(
+        BOOST_ASIO_MOVE_CAST(RawCompletionToken)(token),
+        BOOST_ASIO_MOVE_CAST(Args)(args)...);
+  }
+
+#else // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+      //   || defined(GENERATING_DOCUMENTATION)
+
+  template <typename Initiation, typename RawCompletionToken>
+  static return_type initiate(
+      BOOST_ASIO_MOVE_ARG(Initiation) initiation,
+      BOOST_ASIO_MOVE_ARG(RawCompletionToken) token)
+  {
+    BOOST_ASIO_MOVE_CAST(Initiation)(initiation)(
+        BOOST_ASIO_MOVE_CAST(RawCompletionToken)(token));
+  }
+
+#define BOOST_ASIO_PRIVATE_INITIATE_DEF(n) \
+  template <typename Initiation, typename RawCompletionToken, \
+      BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  static return_type initiate( \
+      BOOST_ASIO_MOVE_ARG(Initiation) initiation, \
+      BOOST_ASIO_MOVE_ARG(RawCompletionToken) token, \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n)) \
+  { \
+    BOOST_ASIO_MOVE_CAST(Initiation)(initiation)( \
+        BOOST_ASIO_MOVE_CAST(RawCompletionToken)(token), \
+        BOOST_ASIO_VARIADIC_MOVE_ARGS(n)); \
+  } \
+  /**/
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_INITIATE_DEF)
+#undef BOOST_ASIO_PRIVATE_INITIATE_DEF
+
+#endif // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+       //   || defined(GENERATING_DOCUMENTATION)
+
+private:
+  async_result(const async_result&) BOOST_ASIO_DELETED;
+  async_result& operator=(const async_result&) BOOST_ASIO_DELETED;
+};
+
+/// Helper template to deduce the handler type from a CompletionToken, capture
+/// a local copy of the handler, and then create an async_result for the
+/// handler.
+template <typename CompletionToken, typename Signature>
+struct async_completion
+{
+  /// The real handler type to be used for the asynchronous operation.
+  typedef typename boost::asio::async_result<
+    typename decay<CompletionToken>::type,
+      Signature>::completion_handler_type completion_handler_type;
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Constructor.
+  /**
+   * The constructor creates the concrete completion handler and makes the link
+   * between the handler and the asynchronous result.
+   */
+  explicit async_completion(CompletionToken& token)
+    : completion_handler(static_cast<typename conditional<
+        is_same<CompletionToken, completion_handler_type>::value,
+        completion_handler_type&, CompletionToken&&>::type>(token)),
+      result(completion_handler)
+  {
+  }
+#else // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  explicit async_completion(typename decay<CompletionToken>::type& token)
+    : completion_handler(token),
+      result(completion_handler)
+  {
+  }
+
+  explicit async_completion(const typename decay<CompletionToken>::type& token)
+    : completion_handler(token),
+      result(completion_handler)
+  {
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// A copy of, or reference to, a real handler object.
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  typename conditional<
+    is_same<CompletionToken, completion_handler_type>::value,
+    completion_handler_type&, completion_handler_type>::type completion_handler;
+#else // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  completion_handler_type completion_handler;
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// The result of the asynchronous operation's initiating function.
+  async_result<typename decay<CompletionToken>::type, Signature> result;
+};
+
+namespace detail {
+
+template <typename CompletionToken, typename Signature>
+struct async_result_helper
+  : async_result<typename decay<CompletionToken>::type, Signature>
+{
+};
+
+struct async_result_memfns_base
+{
+  void initiate();
+};
+
+template <typename T>
+struct async_result_memfns_derived
+  : T, async_result_memfns_base
+{
+};
+
+template <typename T, T>
+struct async_result_memfns_check
+{
+};
+
+template <typename>
+char (&async_result_initiate_memfn_helper(...))[2];
+
+template <typename T>
+char async_result_initiate_memfn_helper(
+    async_result_memfns_check<
+      void (async_result_memfns_base::*)(),
+      &async_result_memfns_derived<T>::initiate>*);
+
+template <typename CompletionToken, typename Signature>
+struct async_result_has_initiate_memfn
+  : integral_constant<bool, sizeof(async_result_initiate_memfn_helper<
+      async_result<typename decay<CompletionToken>::type, Signature>
+    >(0)) != 1>
+{
+};
+
+} // namespace detail
+
+#if defined(GENERATING_DOCUMENTATION)
+# define BOOST_ASIO_INITFN_RESULT_TYPE(ct, sig) \
+  void_or_deduced
+#elif defined(_MSC_VER) && (_MSC_VER < 1500)
+# define BOOST_ASIO_INITFN_RESULT_TYPE(ct, sig) \
+  typename ::boost::asio::detail::async_result_helper< \
+    ct, sig>::return_type
+#define BOOST_ASIO_HANDLER_TYPE(ct, sig) \
+  typename ::boost::asio::detail::async_result_helper< \
+    ct, sig>::completion_handler_type
+#else
+# define BOOST_ASIO_INITFN_RESULT_TYPE(ct, sig) \
+  typename ::boost::asio::async_result< \
+    typename ::boost::asio::decay<ct>::type, sig>::return_type
+#define BOOST_ASIO_HANDLER_TYPE(ct, sig) \
+  typename ::boost::asio::async_result< \
+    typename ::boost::asio::decay<ct>::type, sig>::completion_handler_type
+#endif
+
+#if defined(GENERATING_DOCUMENTATION)
+
+template <typename CompletionToken, typename Signature,
+    typename Initiation, typename... Args>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)
+async_initiate(BOOST_ASIO_MOVE_ARG(Initiation) initiation,
+    BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken),
+    BOOST_ASIO_MOVE_ARG(Args)... args);
+
+#elif defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+template <typename CompletionToken, typename Signature,
+    typename Initiation, typename... Args>
+inline typename enable_if<
+    detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
+    BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type
+async_initiate(BOOST_ASIO_MOVE_ARG(Initiation) initiation,
+    BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token,
+    BOOST_ASIO_MOVE_ARG(Args)... args)
+{
+  return async_result<typename decay<CompletionToken>::type,
+    Signature>::initiate(BOOST_ASIO_MOVE_CAST(Initiation)(initiation),
+      BOOST_ASIO_MOVE_CAST(CompletionToken)(token),
+      BOOST_ASIO_MOVE_CAST(Args)(args)...);
+}
+
+template <typename CompletionToken, typename Signature,
+    typename Initiation, typename... Args>
+inline typename enable_if<
+    !detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
+    BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type
+async_initiate(BOOST_ASIO_MOVE_ARG(Initiation) initiation,
+    BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token,
+    BOOST_ASIO_MOVE_ARG(Args)... args)
+{
+  async_completion<CompletionToken, Signature> completion(token);
+
+  BOOST_ASIO_MOVE_CAST(Initiation)(initiation)(
+      BOOST_ASIO_MOVE_CAST(BOOST_ASIO_HANDLER_TYPE(CompletionToken,
+        Signature))(completion.completion_handler),
+      BOOST_ASIO_MOVE_CAST(Args)(args)...);
+
+  return completion.result.get();
+}
+
+#else // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+template <typename CompletionToken, typename Signature, typename Initiation>
+inline typename enable_if<
+    detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
+    BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type
+async_initiate(BOOST_ASIO_MOVE_ARG(Initiation) initiation,
+    BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token)
+{
+  return async_result<typename decay<CompletionToken>::type,
+    Signature>::initiate(BOOST_ASIO_MOVE_CAST(Initiation)(initiation),
+      BOOST_ASIO_MOVE_CAST(CompletionToken)(token));
+}
+
+template <typename CompletionToken, typename Signature, typename Initiation>
+inline typename enable_if<
+    !detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
+    BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type
+async_initiate(BOOST_ASIO_MOVE_ARG(Initiation) initiation,
+    BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token)
+{
+  async_completion<CompletionToken, Signature> completion(token);
+
+  BOOST_ASIO_MOVE_CAST(Initiation)(initiation)(
+      BOOST_ASIO_MOVE_CAST(BOOST_ASIO_HANDLER_TYPE(CompletionToken,
+        Signature))(completion.completion_handler));
+
+  return completion.result.get();
+}
+
+#define BOOST_ASIO_PRIVATE_INITIATE_DEF(n) \
+  template <typename CompletionToken, typename Signature, \
+      typename Initiation, BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  inline typename enable_if< \
+      detail::async_result_has_initiate_memfn< \
+        CompletionToken, Signature>::value, \
+      BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type \
+  async_initiate(BOOST_ASIO_MOVE_ARG(Initiation) initiation, \
+      BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token, \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n)) \
+  { \
+    return async_result<typename decay<CompletionToken>::type, \
+      Signature>::initiate(BOOST_ASIO_MOVE_CAST(Initiation)(initiation), \
+        BOOST_ASIO_MOVE_CAST(CompletionToken)(token), \
+        BOOST_ASIO_VARIADIC_MOVE_ARGS(n)); \
+  } \
+  \
+  template <typename CompletionToken, typename Signature, \
+      typename Initiation, BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  inline typename enable_if< \
+      !detail::async_result_has_initiate_memfn< \
+        CompletionToken, Signature>::value, \
+      BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type \
+  async_initiate(BOOST_ASIO_MOVE_ARG(Initiation) initiation, \
+      BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token, \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n)) \
+  { \
+    async_completion<CompletionToken, Signature> completion(token); \
+  \
+    BOOST_ASIO_MOVE_CAST(Initiation)(initiation)( \
+        BOOST_ASIO_MOVE_CAST(BOOST_ASIO_HANDLER_TYPE(CompletionToken, \
+          Signature))(completion.completion_handler), \
+        BOOST_ASIO_VARIADIC_MOVE_ARGS(n)); \
+  \
+    return completion.result.get(); \
+  } \
+  /**/
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_INITIATE_DEF)
+#undef BOOST_ASIO_PRIVATE_INITIATE_DEF
+
+#endif // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_ASYNC_RESULT_HPP

boost/asio/awaitable.hpp

@@ -0,0 +1,125 @@
+//
+// awaitable.hpp
+// ~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_AWAITABLE_HPP
+#define BOOST_ASIO_AWAITABLE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
+
+#include <experimental/coroutine>
+#include <boost/asio/executor.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+using std::experimental::coroutine_handle;
+using std::experimental::suspend_always;
+
+template <typename> class awaitable_thread;
+template <typename, typename> class awaitable_frame;
+
+} // namespace detail
+
+/// The return type of a coroutine or asynchronous operation.
+template <typename T, typename Executor = executor>
+class awaitable
+{
+public:
+  /// The type of the awaited value.
+  typedef T value_type;
+
+  /// The executor type that will be used for the coroutine.
+  typedef Executor executor_type;
+
+  /// Default constructor.
+  constexpr awaitable() noexcept
+    : frame_(nullptr)
+  {
+  }
+
+  /// Move constructor.
+  awaitable(awaitable&& other) noexcept
+    : frame_(std::exchange(other.frame_, nullptr))
+  {
+  }
+
+  /// Destructor
+  ~awaitable()
+  {
+    if (frame_)
+      frame_->destroy();
+  }
+
+  /// Checks if the awaitable refers to a future result.
+  bool valid() const noexcept
+  {
+    return !!frame_;
+  }
+
+#if !defined(GENERATING_DOCUMENTATION)
+
+  // Support for co_await keyword.
+  bool await_ready() const noexcept
+  {
+    return false;
+  }
+
+  // Support for co_await keyword.
+  template <class U>
+  void await_suspend(
+      detail::coroutine_handle<detail::awaitable_frame<U, Executor>> h)
+  {
+    frame_->push_frame(&h.promise());
+  }
+
+  // Support for co_await keyword.
+  T await_resume()
+  {
+    return frame_->get();
+  }
+
+#endif // !defined(GENERATING_DOCUMENTATION)
+
+private:
+  template <typename> friend class detail::awaitable_thread;
+  template <typename, typename> friend class detail::awaitable_frame;
+
+  // Not copy constructible or copy assignable.
+  awaitable(const awaitable&) = delete;
+  awaitable& operator=(const awaitable&) = delete;
+
+  // Construct the awaitable from a coroutine's frame object.
+  explicit awaitable(detail::awaitable_frame<T, Executor>* a)
+    : frame_(a)
+  {
+  }
+
+  detail::awaitable_frame<T, Executor>* frame_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/impl/awaitable.hpp>
+
+#endif // defined(BOOST_ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
+
+#endif // BOOST_ASIO_AWAITABLE_HPP

boost/asio/basic_deadline_timer.hpp

@@ -0,0 +1,668 @@
+//
+// basic_deadline_timer.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_DEADLINE_TIMER_HPP
+#define BOOST_ASIO_BASIC_DEADLINE_TIMER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  || defined(GENERATING_DOCUMENTATION)
+
+#include <cstddef>
+#include <boost/asio/detail/deadline_timer_service.hpp>
+#include <boost/asio/detail/handler_type_requirements.hpp>
+#include <boost/asio/detail/io_object_impl.hpp>
+#include <boost/asio/detail/non_const_lvalue.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/executor.hpp>
+#include <boost/asio/time_traits.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Provides waitable timer functionality.
+/**
+ * The basic_deadline_timer class template provides the ability to perform a
+ * blocking or asynchronous wait for a timer to expire.
+ *
+ * A deadline timer is always in one of two states: "expired" or "not expired".
+ * If the wait() or async_wait() function is called on an expired timer, the
+ * wait operation will complete immediately.
+ *
+ * Most applications will use the boost::asio::deadline_timer typedef.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ *
+ * @par Examples
+ * Performing a blocking wait:
+ * @code
+ * // Construct a timer without setting an expiry time.
+ * boost::asio::deadline_timer timer(my_context);
+ *
+ * // Set an expiry time relative to now.
+ * timer.expires_from_now(boost::posix_time::seconds(5));
+ *
+ * // Wait for the timer to expire.
+ * timer.wait();
+ * @endcode
+ *
+ * @par 
+ * Performing an asynchronous wait:
+ * @code
+ * void handler(const boost::system::error_code& error)
+ * {
+ *   if (!error)
+ *   {
+ *     // Timer expired.
+ *   }
+ * }
+ *
+ * ...
+ *
+ * // Construct a timer with an absolute expiry time.
+ * boost::asio::deadline_timer timer(my_context,
+ *     boost::posix_time::time_from_string("2005-12-07 23:59:59.000"));
+ *
+ * // Start an asynchronous wait.
+ * timer.async_wait(handler);
+ * @endcode
+ *
+ * @par Changing an active deadline_timer's expiry time
+ *
+ * Changing the expiry time of a timer while there are pending asynchronous
+ * waits causes those wait operations to be cancelled. To ensure that the action
+ * associated with the timer is performed only once, use something like this:
+ * used:
+ *
+ * @code
+ * void on_some_event()
+ * {
+ *   if (my_timer.expires_from_now(seconds(5)) > 0)
+ *   {
+ *     // We managed to cancel the timer. Start new asynchronous wait.
+ *     my_timer.async_wait(on_timeout);
+ *   }
+ *   else
+ *   {
+ *     // Too late, timer has already expired!
+ *   }
+ * }
+ *
+ * void on_timeout(const boost::system::error_code& e)
+ * {
+ *   if (e != boost::asio::error::operation_aborted)
+ *   {
+ *     // Timer was not cancelled, take necessary action.
+ *   }
+ * }
+ * @endcode
+ *
+ * @li The boost::asio::basic_deadline_timer::expires_from_now() function
+ * cancels any pending asynchronous waits, and returns the number of
+ * asynchronous waits that were cancelled. If it returns 0 then you were too
+ * late and the wait handler has already been executed, or will soon be
+ * executed. If it returns 1 then the wait handler was successfully cancelled.
+ *
+ * @li If a wait handler is cancelled, the boost::system::error_code passed to
+ * it contains the value boost::asio::error::operation_aborted.
+ */
+template <typename Time,
+    typename TimeTraits = boost::asio::time_traits<Time>,
+    typename Executor = executor>
+class basic_deadline_timer
+{
+public:
+  /// The type of the executor associated with the object.
+  typedef Executor executor_type;
+
+  /// The time traits type.
+  typedef TimeTraits traits_type;
+
+  /// The time type.
+  typedef typename traits_type::time_type time_type;
+
+  /// The duration type.
+  typedef typename traits_type::duration_type duration_type;
+
+  /// Constructor.
+  /**
+   * This constructor creates a timer without setting an expiry time. The
+   * expires_at() or expires_from_now() functions must be called to set an
+   * expiry time before the timer can be waited on.
+   *
+   * @param ex The I/O executor that the timer will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the timer.
+   */
+  explicit basic_deadline_timer(const executor_type& ex)
+    : impl_(ex)
+  {
+  }
+
+  /// Constructor.
+  /**
+   * This constructor creates a timer without setting an expiry time. The
+   * expires_at() or expires_from_now() functions must be called to set an
+   * expiry time before the timer can be waited on.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the timer will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the timer.
+   */
+  template <typename ExecutionContext>
+  explicit basic_deadline_timer(ExecutionContext& context,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+  }
+
+  /// Constructor to set a particular expiry time as an absolute time.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param ex The I/O executor that the timer will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, expressed
+   * as an absolute time.
+   */
+  basic_deadline_timer(const executor_type& ex, const time_type& expiry_time)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_at");
+  }
+
+  /// Constructor to set a particular expiry time as an absolute time.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the timer will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, expressed
+   * as an absolute time.
+   */
+  template <typename ExecutionContext>
+  basic_deadline_timer(ExecutionContext& context, const time_type& expiry_time,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_at");
+  }
+
+  /// Constructor to set a particular expiry time relative to now.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param ex The I/O executor that the timer will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, relative to
+   * now.
+   */
+  basic_deadline_timer(const executor_type& ex,
+      const duration_type& expiry_time)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_from_now(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_from_now");
+  }
+
+  /// Constructor to set a particular expiry time relative to now.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the timer will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, relative to
+   * now.
+   */
+  template <typename ExecutionContext>
+  basic_deadline_timer(ExecutionContext& context,
+      const duration_type& expiry_time,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_from_now(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_from_now");
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Move-construct a basic_deadline_timer from another.
+  /**
+   * This constructor moves a timer from one object to another.
+   *
+   * @param other The other basic_deadline_timer object from which the move will
+   * occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_deadline_timer(const executor_type&)
+   * constructor.
+   */
+  basic_deadline_timer(basic_deadline_timer&& other)
+    : impl_(std::move(other.impl_))
+  {
+  }
+
+  /// Move-assign a basic_deadline_timer from another.
+  /**
+   * This assignment operator moves a timer from one object to another. Cancels
+   * any outstanding asynchronous operations associated with the target object.
+   *
+   * @param other The other basic_deadline_timer object from which the move will
+   * occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_deadline_timer(const executor_type&)
+   * constructor.
+   */
+  basic_deadline_timer& operator=(basic_deadline_timer&& other)
+  {
+    impl_ = std::move(other.impl_);
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Destroys the timer.
+  /**
+   * This function destroys the timer, cancelling any outstanding asynchronous
+   * wait operations associated with the timer as if by calling @c cancel.
+   */
+  ~basic_deadline_timer()
+  {
+  }
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return impl_.get_executor();
+  }
+
+  /// Cancel any asynchronous operations that are waiting on the timer.
+  /**
+   * This function forces the completion of any pending asynchronous wait
+   * operations against the timer. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when cancel() is called, then the
+   * handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel()
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().cancel(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "cancel");
+    return s;
+  }
+
+  /// Cancel any asynchronous operations that are waiting on the timer.
+  /**
+   * This function forces the completion of any pending asynchronous wait
+   * operations against the timer. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @note If the timer has already expired when cancel() is called, then the
+   * handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel(boost::system::error_code& ec)
+  {
+    return impl_.get_service().cancel(impl_.get_implementation(), ec);
+  }
+
+  /// Cancels one asynchronous operation that is waiting on the timer.
+  /**
+   * This function forces the completion of one pending asynchronous wait
+   * operation against the timer. Handlers are cancelled in FIFO order. The
+   * handler for the cancelled operation will be invoked with the
+   * boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @return The number of asynchronous operations that were cancelled. That is,
+   * either 0 or 1.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when cancel_one() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel_one()
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().cancel_one(
+        impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "cancel_one");
+    return s;
+  }
+
+  /// Cancels one asynchronous operation that is waiting on the timer.
+  /**
+   * This function forces the completion of one pending asynchronous wait
+   * operation against the timer. Handlers are cancelled in FIFO order. The
+   * handler for the cancelled operation will be invoked with the
+   * boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled. That is,
+   * either 0 or 1.
+   *
+   * @note If the timer has already expired when cancel_one() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel_one(boost::system::error_code& ec)
+  {
+    return impl_.get_service().cancel_one(impl_.get_implementation(), ec);
+  }
+
+  /// Get the timer's expiry time as an absolute time.
+  /**
+   * This function may be used to obtain the timer's current expiry time.
+   * Whether the timer has expired or not does not affect this value.
+   */
+  time_type expires_at() const
+  {
+    return impl_.get_service().expires_at(impl_.get_implementation());
+  }
+
+  /// Set the timer's expiry time as an absolute time.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when expires_at() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_at(const time_type& expiry_time)
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().expires_at(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_at");
+    return s;
+  }
+
+  /// Set the timer's expiry time as an absolute time.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @note If the timer has already expired when expires_at() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_at(const time_type& expiry_time,
+      boost::system::error_code& ec)
+  {
+    return impl_.get_service().expires_at(
+        impl_.get_implementation(), expiry_time, ec);
+  }
+
+  /// Get the timer's expiry time relative to now.
+  /**
+   * This function may be used to obtain the timer's current expiry time.
+   * Whether the timer has expired or not does not affect this value.
+   */
+  duration_type expires_from_now() const
+  {
+    return impl_.get_service().expires_from_now(impl_.get_implementation());
+  }
+
+  /// Set the timer's expiry time relative to now.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when expires_from_now() is called,
+   * then the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_from_now(const duration_type& expiry_time)
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().expires_from_now(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_from_now");
+    return s;
+  }
+
+  /// Set the timer's expiry time relative to now.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @note If the timer has already expired when expires_from_now() is called,
+   * then the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_from_now(const duration_type& expiry_time,
+      boost::system::error_code& ec)
+  {
+    return impl_.get_service().expires_from_now(
+        impl_.get_implementation(), expiry_time, ec);
+  }
+
+  /// Perform a blocking wait on the timer.
+  /**
+   * This function is used to wait for the timer to expire. This function
+   * blocks and does not return until the timer has expired.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void wait()
+  {
+    boost::system::error_code ec;
+    impl_.get_service().wait(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "wait");
+  }
+
+  /// Perform a blocking wait on the timer.
+  /**
+   * This function is used to wait for the timer to expire. This function
+   * blocks and does not return until the timer has expired.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   */
+  void wait(boost::system::error_code& ec)
+  {
+    impl_.get_service().wait(impl_.get_implementation(), ec);
+  }
+
+  /// Start an asynchronous wait on the timer.
+  /**
+   * This function may be used to initiate an asynchronous wait against the
+   * timer. It always returns immediately.
+   *
+   * For each call to async_wait(), the supplied handler will be called exactly
+   * once. The handler will be called when:
+   *
+   * @li The timer has expired.
+   *
+   * @li The timer was cancelled, in which case the handler is passed the error
+   * code boost::asio::error::operation_aborted.
+   *
+   * @param handler The handler to be called when the timer expires. Copies
+   * will be made of the handler as required. The function signature of the
+   * handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error // Result of operation.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   */
+  template <typename WaitHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WaitHandler,
+      void (boost::system::error_code))
+  async_wait(BOOST_ASIO_MOVE_ARG(WaitHandler) handler)
+  {
+    return async_initiate<WaitHandler, void (boost::system::error_code)>(
+        initiate_async_wait(), handler, this);
+  }
+
+private:
+  // Disallow copying and assignment.
+  basic_deadline_timer(const basic_deadline_timer&) BOOST_ASIO_DELETED;
+  basic_deadline_timer& operator=(
+      const basic_deadline_timer&) BOOST_ASIO_DELETED;
+
+  struct initiate_async_wait
+  {
+    template <typename WaitHandler>
+    void operator()(BOOST_ASIO_MOVE_ARG(WaitHandler) handler,
+        basic_deadline_timer* self) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a WaitHandler.
+      BOOST_ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
+
+      detail::non_const_lvalue<WaitHandler> handler2(handler);
+      self->impl_.get_service().async_wait(
+          self->impl_.get_implementation(), handler2.value,
+          self->impl_.get_implementation_executor());
+    }
+  };
+
+  detail::io_object_impl<
+    detail::deadline_timer_service<TimeTraits>, Executor> impl_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // || defined(GENERATING_DOCUMENTATION)
+
+#endif // BOOST_ASIO_BASIC_DEADLINE_TIMER_HPP

boost/asio/basic_io_object.hpp

@@ -0,0 +1,292 @@
+//
+// basic_io_object.hpp
+// ~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_IO_OBJECT_HPP
+#define BOOST_ASIO_BASIC_IO_OBJECT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/io_context.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+namespace detail
+{
+  // Type trait used to determine whether a service supports move.
+  template <typename IoObjectService>
+  class service_has_move
+  {
+  private:
+    typedef IoObjectService service_type;
+    typedef typename service_type::implementation_type implementation_type;
+
+    template <typename T, typename U>
+    static auto asio_service_has_move_eval(T* t, U* u)
+      -> decltype(t->move_construct(*u, *u), char());
+    static char (&asio_service_has_move_eval(...))[2];
+
+  public:
+    static const bool value =
+      sizeof(asio_service_has_move_eval(
+        static_cast<service_type*>(0),
+        static_cast<implementation_type*>(0))) == 1;
+  };
+}
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+/// Base class for all I/O objects.
+/**
+ * @note All I/O objects are non-copyable. However, when using C++0x, certain
+ * I/O objects do support move construction and move assignment.
+ */
+#if !defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+template <typename IoObjectService>
+#else
+template <typename IoObjectService,
+    bool Movable = detail::service_has_move<IoObjectService>::value>
+#endif
+class basic_io_object
+{
+public:
+  /// The type of the service that will be used to provide I/O operations.
+  typedef IoObjectService service_type;
+
+  /// The underlying implementation type of I/O object.
+  typedef typename service_type::implementation_type implementation_type;
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use get_executor().) Get the io_context associated with the
+  /// object.
+  /**
+   * This function may be used to obtain the io_context object that the I/O
+   * object uses to dispatch handlers for asynchronous operations.
+   *
+   * @return A reference to the io_context object that the I/O object will use
+   * to dispatch handlers. Ownership is not transferred to the caller.
+   */
+  boost::asio::io_context& get_io_context()
+  {
+    return service_.get_io_context();
+  }
+
+  /// (Deprecated: Use get_executor().) Get the io_context associated with the
+  /// object.
+  /**
+   * This function may be used to obtain the io_context object that the I/O
+   * object uses to dispatch handlers for asynchronous operations.
+   *
+   * @return A reference to the io_context object that the I/O object will use
+   * to dispatch handlers. Ownership is not transferred to the caller.
+   */
+  boost::asio::io_context& get_io_service()
+  {
+    return service_.get_io_context();
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  /// The type of the executor associated with the object.
+  typedef boost::asio::io_context::executor_type executor_type;
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return service_.get_io_context().get_executor();
+  }
+
+protected:
+  /// Construct a basic_io_object.
+  /**
+   * Performs:
+   * @code get_service().construct(get_implementation()); @endcode
+   */
+  explicit basic_io_object(boost::asio::io_context& io_context)
+    : service_(boost::asio::use_service<IoObjectService>(io_context))
+  {
+    service_.construct(implementation_);
+  }
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// Move-construct a basic_io_object.
+  /**
+   * Performs:
+   * @code get_service().move_construct(
+   *     get_implementation(), other.get_implementation()); @endcode
+   *
+   * @note Available only for services that support movability,
+   */
+  basic_io_object(basic_io_object&& other);
+
+  /// Move-assign a basic_io_object.
+  /**
+   * Performs:
+   * @code get_service().move_assign(get_implementation(),
+   *     other.get_service(), other.get_implementation()); @endcode
+   *
+   * @note Available only for services that support movability,
+   */
+  basic_io_object& operator=(basic_io_object&& other);
+
+  /// Perform a converting move-construction of a basic_io_object.
+  template <typename IoObjectService1>
+  basic_io_object(IoObjectService1& other_service,
+      typename IoObjectService1::implementation_type& other_implementation);
+#endif // defined(GENERATING_DOCUMENTATION)
+
+  /// Protected destructor to prevent deletion through this type.
+  /**
+   * Performs:
+   * @code get_service().destroy(get_implementation()); @endcode
+   */
+  ~basic_io_object()
+  {
+    service_.destroy(implementation_);
+  }
+
+  /// Get the service associated with the I/O object.
+  service_type& get_service()
+  {
+    return service_;
+  }
+
+  /// Get the service associated with the I/O object.
+  const service_type& get_service() const
+  {
+    return service_;
+  }
+
+  /// Get the underlying implementation of the I/O object.
+  implementation_type& get_implementation()
+  {
+    return implementation_;
+  }
+
+  /// Get the underlying implementation of the I/O object.
+  const implementation_type& get_implementation() const
+  {
+    return implementation_;
+  }
+
+private:
+  basic_io_object(const basic_io_object&);
+  basic_io_object& operator=(const basic_io_object&);
+
+  // The service associated with the I/O object.
+  service_type& service_;
+
+  /// The underlying implementation of the I/O object.
+  implementation_type implementation_;
+};
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+// Specialisation for movable objects.
+template <typename IoObjectService>
+class basic_io_object<IoObjectService, true>
+{
+public:
+  typedef IoObjectService service_type;
+  typedef typename service_type::implementation_type implementation_type;
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  boost::asio::io_context& get_io_context()
+  {
+    return service_->get_io_context();
+  }
+
+  boost::asio::io_context& get_io_service()
+  {
+    return service_->get_io_context();
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  typedef boost::asio::io_context::executor_type executor_type;
+
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return service_->get_io_context().get_executor();
+  }
+
+protected:
+  explicit basic_io_object(boost::asio::io_context& io_context)
+    : service_(&boost::asio::use_service<IoObjectService>(io_context))
+  {
+    service_->construct(implementation_);
+  }
+
+  basic_io_object(basic_io_object&& other)
+    : service_(&other.get_service())
+  {
+    service_->move_construct(implementation_, other.implementation_);
+  }
+
+  template <typename IoObjectService1>
+  basic_io_object(IoObjectService1& other_service,
+      typename IoObjectService1::implementation_type& other_implementation)
+    : service_(&boost::asio::use_service<IoObjectService>(
+          other_service.get_io_context()))
+  {
+    service_->converting_move_construct(implementation_,
+        other_service, other_implementation);
+  }
+
+  ~basic_io_object()
+  {
+    service_->destroy(implementation_);
+  }
+
+  basic_io_object& operator=(basic_io_object&& other)
+  {
+    service_->move_assign(implementation_,
+        *other.service_, other.implementation_);
+    service_ = other.service_;
+    return *this;
+  }
+
+  service_type& get_service()
+  {
+    return *service_;
+  }
+
+  const service_type& get_service() const
+  {
+    return *service_;
+  }
+
+  implementation_type& get_implementation()
+  {
+    return implementation_;
+  }
+
+  const implementation_type& get_implementation() const
+  {
+    return implementation_;
+  }
+
+private:
+  basic_io_object(const basic_io_object&);
+  void operator=(const basic_io_object&);
+
+  IoObjectService* service_;
+  implementation_type implementation_;
+};
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_BASIC_IO_OBJECT_HPP

boost/asio/basic_seq_packet_socket.hpp

@@ -0,0 +1,714 @@
+//
+// basic_seq_packet_socket.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_SEQ_PACKET_SOCKET_HPP
+#define BOOST_ASIO_BASIC_SEQ_PACKET_SOCKET_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/basic_socket.hpp>
+#include <boost/asio/detail/handler_type_requirements.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+#include <boost/asio/error.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+#if !defined(BOOST_ASIO_BASIC_SEQ_PACKET_SOCKET_FWD_DECL)
+#define BOOST_ASIO_BASIC_SEQ_PACKET_SOCKET_FWD_DECL
+
+// Forward declaration with defaulted arguments.
+template <typename Protocol, typename Executor = executor>
+class basic_seq_packet_socket;
+
+#endif // !defined(BOOST_ASIO_BASIC_SEQ_PACKET_SOCKET_FWD_DECL)
+
+/// Provides sequenced packet socket functionality.
+/**
+ * The basic_seq_packet_socket class template provides asynchronous and blocking
+ * sequenced packet socket functionality.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ */
+template <typename Protocol, typename Executor>
+class basic_seq_packet_socket
+  : public basic_socket<Protocol, Executor>
+{
+public:
+  /// The type of the executor associated with the object.
+  typedef Executor executor_type;
+
+  /// Rebinds the socket type to another executor.
+  template <typename Executor1>
+  struct rebind_executor
+  {
+    /// The socket type when rebound to the specified executor.
+    typedef basic_seq_packet_socket<Protocol, Executor1> other;
+  };
+
+  /// The native representation of a socket.
+#if defined(GENERATING_DOCUMENTATION)
+  typedef implementation_defined native_handle_type;
+#else
+  typedef typename basic_socket<Protocol,
+    Executor>::native_handle_type native_handle_type;
+#endif
+
+  /// The protocol type.
+  typedef Protocol protocol_type;
+
+  /// The endpoint type.
+  typedef typename Protocol::endpoint endpoint_type;
+
+  /// Construct a basic_seq_packet_socket without opening it.
+  /**
+   * This constructor creates a sequenced packet socket without opening it. The
+   * socket needs to be opened and then connected or accepted before data can
+   * be sent or received on it.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   */
+  explicit basic_seq_packet_socket(const executor_type& ex)
+    : basic_socket<Protocol, Executor>(ex)
+  {
+  }
+
+  /// Construct a basic_seq_packet_socket without opening it.
+  /**
+   * This constructor creates a sequenced packet socket without opening it. The
+   * socket needs to be opened and then connected or accepted before data can
+   * be sent or received on it.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   */
+  template <typename ExecutionContext>
+  explicit basic_seq_packet_socket(ExecutionContext& context,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context)
+  {
+  }
+
+  /// Construct and open a basic_seq_packet_socket.
+  /**
+   * This constructor creates and opens a sequenced_packet socket. The socket
+   * needs to be connected or accepted before data can be sent or received on
+   * it.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  basic_seq_packet_socket(const executor_type& ex,
+      const protocol_type& protocol)
+    : basic_socket<Protocol, Executor>(ex, protocol)
+  {
+  }
+
+  /// Construct and open a basic_seq_packet_socket.
+  /**
+   * This constructor creates and opens a sequenced_packet socket. The socket
+   * needs to be connected or accepted before data can be sent or received on
+   * it.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  template <typename ExecutionContext>
+  basic_seq_packet_socket(ExecutionContext& context,
+      const protocol_type& protocol,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context, protocol)
+  {
+  }
+
+  /// Construct a basic_seq_packet_socket, opening it and binding it to the
+  /// given local endpoint.
+  /**
+   * This constructor creates a sequenced packet socket and automatically opens
+   * it bound to the specified endpoint on the local machine. The protocol used
+   * is the protocol associated with the given endpoint.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   *
+   * @param endpoint An endpoint on the local machine to which the sequenced
+   * packet socket will be bound.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  basic_seq_packet_socket(const executor_type& ex,
+      const endpoint_type& endpoint)
+    : basic_socket<Protocol, Executor>(ex, endpoint)
+  {
+  }
+
+  /// Construct a basic_seq_packet_socket, opening it and binding it to the
+  /// given local endpoint.
+  /**
+   * This constructor creates a sequenced packet socket and automatically opens
+   * it bound to the specified endpoint on the local machine. The protocol used
+   * is the protocol associated with the given endpoint.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   *
+   * @param endpoint An endpoint on the local machine to which the sequenced
+   * packet socket will be bound.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  template <typename ExecutionContext>
+  basic_seq_packet_socket(ExecutionContext& context,
+      const endpoint_type& endpoint,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context, endpoint)
+  {
+  }
+
+  /// Construct a basic_seq_packet_socket on an existing native socket.
+  /**
+   * This constructor creates a sequenced packet socket object to hold an
+   * existing native socket.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @param native_socket The new underlying socket implementation.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  basic_seq_packet_socket(const executor_type& ex,
+      const protocol_type& protocol, const native_handle_type& native_socket)
+    : basic_socket<Protocol, Executor>(ex, protocol, native_socket)
+  {
+  }
+
+  /// Construct a basic_seq_packet_socket on an existing native socket.
+  /**
+   * This constructor creates a sequenced packet socket object to hold an
+   * existing native socket.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @param native_socket The new underlying socket implementation.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  template <typename ExecutionContext>
+  basic_seq_packet_socket(ExecutionContext& context,
+      const protocol_type& protocol, const native_handle_type& native_socket,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context, protocol, native_socket)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Move-construct a basic_seq_packet_socket from another.
+  /**
+   * This constructor moves a sequenced packet socket from one object to
+   * another.
+   *
+   * @param other The other basic_seq_packet_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_seq_packet_socket(const executor_type&)
+   * constructor.
+   */
+  basic_seq_packet_socket(basic_seq_packet_socket&& other)
+    : basic_socket<Protocol, Executor>(std::move(other))
+  {
+  }
+
+  /// Move-assign a basic_seq_packet_socket from another.
+  /**
+   * This assignment operator moves a sequenced packet socket from one object to
+   * another.
+   *
+   * @param other The other basic_seq_packet_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_seq_packet_socket(const executor_type&)
+   * constructor.
+   */
+  basic_seq_packet_socket& operator=(basic_seq_packet_socket&& other)
+  {
+    basic_socket<Protocol, Executor>::operator=(std::move(other));
+    return *this;
+  }
+
+  /// Move-construct a basic_seq_packet_socket from a socket of another protocol
+  /// type.
+  /**
+   * This constructor moves a sequenced packet socket from one object to
+   * another.
+   *
+   * @param other The other basic_seq_packet_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_seq_packet_socket(const executor_type&)
+   * constructor.
+   */
+  template <typename Protocol1, typename Executor1>
+  basic_seq_packet_socket(basic_seq_packet_socket<Protocol1, Executor1>&& other,
+      typename enable_if<
+        is_convertible<Protocol1, Protocol>::value
+          && is_convertible<Executor1, Executor>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(std::move(other))
+  {
+  }
+
+  /// Move-assign a basic_seq_packet_socket from a socket of another protocol
+  /// type.
+  /**
+   * This assignment operator moves a sequenced packet socket from one object to
+   * another.
+   *
+   * @param other The other basic_seq_packet_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_seq_packet_socket(const executor_type&)
+   * constructor.
+   */
+  template <typename Protocol1, typename Executor1>
+  typename enable_if<
+    is_convertible<Protocol1, Protocol>::value
+      && is_convertible<Executor1, Executor>::value,
+    basic_seq_packet_socket&
+  >::type operator=(basic_seq_packet_socket<Protocol1, Executor1>&& other)
+  {
+    basic_socket<Protocol, Executor>::operator=(std::move(other));
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Destroys the socket.
+  /**
+   * This function destroys the socket, cancelling any outstanding asynchronous
+   * operations associated with the socket as if by calling @c cancel.
+   */
+  ~basic_seq_packet_socket()
+  {
+  }
+
+  /// Send some data on the socket.
+  /**
+   * This function is used to send data on the sequenced packet socket. The
+   * function call will block until the data has been sent successfully, or an
+   * until error occurs.
+   *
+   * @param buffers One or more data buffers to be sent on the socket.
+   *
+   * @param flags Flags specifying how the send call is to be made.
+   *
+   * @returns The number of bytes sent.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @par Example
+   * To send a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.send(boost::asio::buffer(data, size), 0);
+   * @endcode
+   * See the @ref buffer documentation for information on sending multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t send(const ConstBufferSequence& buffers,
+      socket_base::message_flags flags)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().send(
+        this->impl_.get_implementation(), buffers, flags, ec);
+    boost::asio::detail::throw_error(ec, "send");
+    return s;
+  }
+
+  /// Send some data on the socket.
+  /**
+   * This function is used to send data on the sequenced packet socket. The
+   * function call will block the data has been sent successfully, or an until
+   * error occurs.
+   *
+   * @param buffers One or more data buffers to be sent on the socket.
+   *
+   * @param flags Flags specifying how the send call is to be made.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes sent. Returns 0 if an error occurred.
+   *
+   * @note The send operation may not transmit all of the data to the peer.
+   * Consider using the @ref write function if you need to ensure that all data
+   * is written before the blocking operation completes.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t send(const ConstBufferSequence& buffers,
+      socket_base::message_flags flags, boost::system::error_code& ec)
+  {
+    return this->impl_.get_service().send(
+        this->impl_.get_implementation(), buffers, flags, ec);
+  }
+
+  /// Start an asynchronous send.
+  /**
+   * This function is used to asynchronously send data on the sequenced packet
+   * socket. The function call always returns immediately.
+   *
+   * @param buffers One or more data buffers to be sent on the socket. Although
+   * the buffers object may be copied as necessary, ownership of the underlying
+   * memory blocks is retained by the caller, which must guarantee that they
+   * remain valid until the handler is called.
+   *
+   * @param flags Flags specifying how the send call is to be made.
+   *
+   * @param handler The handler to be called when the send operation completes.
+   * Copies will be made of the handler as required. The function signature of
+   * the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes sent.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @par Example
+   * To send a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.async_send(boost::asio::buffer(data, size), 0, handler);
+   * @endcode
+   * See the @ref buffer documentation for information on sending multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_send(const ConstBufferSequence& buffers,
+      socket_base::message_flags flags,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return async_initiate<WriteHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_send(), handler, this, buffers, flags);
+  }
+
+  /// Receive some data on the socket.
+  /**
+   * This function is used to receive data on the sequenced packet socket. The
+   * function call will block until data has been received successfully, or
+   * until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   *
+   * @param out_flags After the receive call completes, contains flags
+   * associated with the received data. For example, if the
+   * socket_base::message_end_of_record bit is set then the received data marks
+   * the end of a record.
+   *
+   * @returns The number of bytes received.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.receive(boost::asio::buffer(data, size), out_flags);
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags& out_flags)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().receive_with_flags(
+        this->impl_.get_implementation(), buffers, 0, out_flags, ec);
+    boost::asio::detail::throw_error(ec, "receive");
+    return s;
+  }
+
+  /// Receive some data on the socket.
+  /**
+   * This function is used to receive data on the sequenced packet socket. The
+   * function call will block until data has been received successfully, or
+   * until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   *
+   * @param in_flags Flags specifying how the receive call is to be made.
+   *
+   * @param out_flags After the receive call completes, contains flags
+   * associated with the received data. For example, if the
+   * socket_base::message_end_of_record bit is set then the received data marks
+   * the end of a record.
+   *
+   * @returns The number of bytes received.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @note The receive operation may not receive all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that the
+   * requested amount of data is read before the blocking operation completes.
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.receive(boost::asio::buffer(data, size), 0, out_flags);
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags in_flags,
+      socket_base::message_flags& out_flags)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().receive_with_flags(
+        this->impl_.get_implementation(), buffers, in_flags, out_flags, ec);
+    boost::asio::detail::throw_error(ec, "receive");
+    return s;
+  }
+
+  /// Receive some data on a connected socket.
+  /**
+   * This function is used to receive data on the sequenced packet socket. The
+   * function call will block until data has been received successfully, or
+   * until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   *
+   * @param in_flags Flags specifying how the receive call is to be made.
+   *
+   * @param out_flags After the receive call completes, contains flags
+   * associated with the received data. For example, if the
+   * socket_base::message_end_of_record bit is set then the received data marks
+   * the end of a record.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes received. Returns 0 if an error occurred.
+   *
+   * @note The receive operation may not receive all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that the
+   * requested amount of data is read before the blocking operation completes.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags in_flags,
+      socket_base::message_flags& out_flags, boost::system::error_code& ec)
+  {
+    return this->impl_.get_service().receive_with_flags(
+        this->impl_.get_implementation(), buffers, in_flags, out_flags, ec);
+  }
+
+  /// Start an asynchronous receive.
+  /**
+   * This function is used to asynchronously receive data from the sequenced
+   * packet socket. The function call always returns immediately.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param out_flags Once the asynchronous operation completes, contains flags
+   * associated with the received data. For example, if the
+   * socket_base::message_end_of_record bit is set then the received data marks
+   * the end of a record. The caller must guarantee that the referenced
+   * variable remains valid until the handler is called.
+   *
+   * @param handler The handler to be called when the receive operation
+   * completes. Copies will be made of the handler as required. The function
+   * signature of the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes received.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.async_receive(boost::asio::buffer(data, size), out_flags, handler);
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags& out_flags,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return async_initiate<ReadHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_receive_with_flags(), handler, this,
+        buffers, socket_base::message_flags(0), &out_flags);
+  }
+
+  /// Start an asynchronous receive.
+  /**
+   * This function is used to asynchronously receive data from the sequenced
+   * data socket. The function call always returns immediately.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param in_flags Flags specifying how the receive call is to be made.
+   *
+   * @param out_flags Once the asynchronous operation completes, contains flags
+   * associated with the received data. For example, if the
+   * socket_base::message_end_of_record bit is set then the received data marks
+   * the end of a record. The caller must guarantee that the referenced
+   * variable remains valid until the handler is called.
+   *
+   * @param handler The handler to be called when the receive operation
+   * completes. Copies will be made of the handler as required. The function
+   * signature of the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes received.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.async_receive(
+   *     boost::asio::buffer(data, size),
+   *     0, out_flags, handler);
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags in_flags,
+      socket_base::message_flags& out_flags,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return async_initiate<ReadHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_receive_with_flags(), handler,
+        this, buffers, in_flags, &out_flags);
+  }
+
+private:
+  struct initiate_async_send
+  {
+    template <typename WriteHandler, typename ConstBufferSequence>
+    void operator()(BOOST_ASIO_MOVE_ARG(WriteHandler) handler,
+        basic_seq_packet_socket* self, const ConstBufferSequence& buffers,
+        socket_base::message_flags flags) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a WriteHandler.
+      BOOST_ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
+
+      detail::non_const_lvalue<WriteHandler> handler2(handler);
+      self->impl_.get_service().async_send(
+          self->impl_.get_implementation(), buffers, flags,
+          handler2.value, self->impl_.get_implementation_executor());
+    }
+  };
+
+  struct initiate_async_receive_with_flags
+  {
+    template <typename ReadHandler, typename MutableBufferSequence>
+    void operator()(BOOST_ASIO_MOVE_ARG(ReadHandler) handler,
+        basic_seq_packet_socket* self, const MutableBufferSequence& buffers,
+        socket_base::message_flags in_flags,
+        socket_base::message_flags* out_flags) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a ReadHandler.
+      BOOST_ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
+
+      detail::non_const_lvalue<ReadHandler> handler2(handler);
+      self->impl_.get_service().async_receive_with_flags(
+          self->impl_.get_implementation(), buffers, in_flags, *out_flags,
+          handler2.value, self->impl_.get_implementation_executor());
+    }
+  };
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_BASIC_SEQ_PACKET_SOCKET_HPP

boost/asio/basic_serial_port.hpp

@@ -0,0 +1,861 @@
+//
+// basic_serial_port.hpp
+// ~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_SERIAL_PORT_HPP
+#define BOOST_ASIO_BASIC_SERIAL_PORT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_SERIAL_PORT) \
+  || defined(GENERATING_DOCUMENTATION)
+
+#include <string>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/detail/handler_type_requirements.hpp>
+#include <boost/asio/detail/io_object_impl.hpp>
+#include <boost/asio/detail/non_const_lvalue.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/executor.hpp>
+#include <boost/asio/serial_port_base.hpp>
+#if defined(BOOST_ASIO_HAS_IOCP)
+# include <boost/asio/detail/win_iocp_serial_port_service.hpp>
+#else
+# include <boost/asio/detail/reactive_serial_port_service.hpp>
+#endif
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+# include <utility>
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Provides serial port functionality.
+/**
+ * The basic_serial_port class provides a wrapper over serial port
+ * functionality.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ */
+template <typename Executor = executor>
+class basic_serial_port
+  : public serial_port_base
+{
+public:
+  /// The type of the executor associated with the object.
+  typedef Executor executor_type;
+
+  /// The native representation of a serial port.
+#if defined(GENERATING_DOCUMENTATION)
+  typedef implementation_defined native_handle_type;
+#elif defined(BOOST_ASIO_HAS_IOCP)
+  typedef detail::win_iocp_serial_port_service::native_handle_type
+    native_handle_type;
+#else
+  typedef detail::reactive_serial_port_service::native_handle_type
+    native_handle_type;
+#endif
+
+  /// A basic_basic_serial_port is always the lowest layer.
+  typedef basic_serial_port lowest_layer_type;
+
+  /// Construct a basic_serial_port without opening it.
+  /**
+   * This constructor creates a serial port without opening it.
+   *
+   * @param ex The I/O executor that the serial port will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * serial port.
+   */
+  explicit basic_serial_port(const executor_type& ex)
+    : impl_(ex)
+  {
+  }
+
+  /// Construct a basic_serial_port without opening it.
+  /**
+   * This constructor creates a serial port without opening it.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the serial port will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the serial port.
+   */
+  template <typename ExecutionContext>
+  explicit basic_serial_port(ExecutionContext& context,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value,
+        basic_serial_port
+      >::type* = 0)
+    : impl_(context)
+  {
+  }
+
+  /// Construct and open a basic_serial_port.
+  /**
+   * This constructor creates and opens a serial port for the specified device
+   * name.
+   *
+   * @param ex The I/O executor that the serial port will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * serial port.
+   *
+   * @param device The platform-specific device name for this serial
+   * port.
+   */
+  basic_serial_port(const executor_type& ex, const char* device)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().open(impl_.get_implementation(), device, ec);
+    boost::asio::detail::throw_error(ec, "open");
+  }
+
+  /// Construct and open a basic_serial_port.
+  /**
+   * This constructor creates and opens a serial port for the specified device
+   * name.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the serial port will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the serial port.
+   *
+   * @param device The platform-specific device name for this serial
+   * port.
+   */
+  template <typename ExecutionContext>
+  basic_serial_port(ExecutionContext& context, const char* device,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().open(impl_.get_implementation(), device, ec);
+    boost::asio::detail::throw_error(ec, "open");
+  }
+
+  /// Construct and open a basic_serial_port.
+  /**
+   * This constructor creates and opens a serial port for the specified device
+   * name.
+   *
+   * @param ex The I/O executor that the serial port will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * serial port.
+   *
+   * @param device The platform-specific device name for this serial
+   * port.
+   */
+  basic_serial_port(const executor_type& ex, const std::string& device)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().open(impl_.get_implementation(), device, ec);
+    boost::asio::detail::throw_error(ec, "open");
+  }
+
+  /// Construct and open a basic_serial_port.
+  /**
+   * This constructor creates and opens a serial port for the specified device
+   * name.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the serial port will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the serial port.
+   *
+   * @param device The platform-specific device name for this serial
+   * port.
+   */
+  template <typename ExecutionContext>
+  basic_serial_port(ExecutionContext& context, const std::string& device,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().open(impl_.get_implementation(), device, ec);
+    boost::asio::detail::throw_error(ec, "open");
+  }
+
+  /// Construct a basic_serial_port on an existing native serial port.
+  /**
+   * This constructor creates a serial port object to hold an existing native
+   * serial port.
+   *
+   * @param ex The I/O executor that the serial port will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * serial port.
+   *
+   * @param native_serial_port A native serial port.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  basic_serial_port(const executor_type& ex,
+      const native_handle_type& native_serial_port)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().assign(impl_.get_implementation(),
+        native_serial_port, ec);
+    boost::asio::detail::throw_error(ec, "assign");
+  }
+
+  /// Construct a basic_serial_port on an existing native serial port.
+  /**
+   * This constructor creates a serial port object to hold an existing native
+   * serial port.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the serial port will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the serial port.
+   *
+   * @param native_serial_port A native serial port.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  template <typename ExecutionContext>
+  basic_serial_port(ExecutionContext& context,
+      const native_handle_type& native_serial_port,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().assign(impl_.get_implementation(),
+        native_serial_port, ec);
+    boost::asio::detail::throw_error(ec, "assign");
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Move-construct a basic_serial_port from another.
+  /**
+   * This constructor moves a serial port from one object to another.
+   *
+   * @param other The other basic_serial_port object from which the move will
+   * occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_serial_port(const executor_type&)
+   * constructor.
+   */
+  basic_serial_port(basic_serial_port&& other)
+    : impl_(std::move(other.impl_))
+  {
+  }
+
+  /// Move-assign a basic_serial_port from another.
+  /**
+   * This assignment operator moves a serial port from one object to another.
+   *
+   * @param other The other basic_serial_port object from which the move will
+   * occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_serial_port(const executor_type&)
+   * constructor.
+   */
+  basic_serial_port& operator=(basic_serial_port&& other)
+  {
+    impl_ = std::move(other.impl_);
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Destroys the serial port.
+  /**
+   * This function destroys the serial port, cancelling any outstanding
+   * asynchronous wait operations associated with the serial port as if by
+   * calling @c cancel.
+   */
+  ~basic_serial_port()
+  {
+  }
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return impl_.get_executor();
+  }
+
+  /// Get a reference to the lowest layer.
+  /**
+   * This function returns a reference to the lowest layer in a stack of
+   * layers. Since a basic_serial_port cannot contain any further layers, it
+   * simply returns a reference to itself.
+   *
+   * @return A reference to the lowest layer in the stack of layers. Ownership
+   * is not transferred to the caller.
+   */
+  lowest_layer_type& lowest_layer()
+  {
+    return *this;
+  }
+
+  /// Get a const reference to the lowest layer.
+  /**
+   * This function returns a const reference to the lowest layer in a stack of
+   * layers. Since a basic_serial_port cannot contain any further layers, it
+   * simply returns a reference to itself.
+   *
+   * @return A const reference to the lowest layer in the stack of layers.
+   * Ownership is not transferred to the caller.
+   */
+  const lowest_layer_type& lowest_layer() const
+  {
+    return *this;
+  }
+
+  /// Open the serial port using the specified device name.
+  /**
+   * This function opens the serial port for the specified device name.
+   *
+   * @param device The platform-specific device name.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void open(const std::string& device)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().open(impl_.get_implementation(), device, ec);
+    boost::asio::detail::throw_error(ec, "open");
+  }
+
+  /// Open the serial port using the specified device name.
+  /**
+   * This function opens the serial port using the given platform-specific
+   * device name.
+   *
+   * @param device The platform-specific device name.
+   *
+   * @param ec Set the indicate what error occurred, if any.
+   */
+  BOOST_ASIO_SYNC_OP_VOID open(const std::string& device,
+      boost::system::error_code& ec)
+  {
+    impl_.get_service().open(impl_.get_implementation(), device, ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Assign an existing native serial port to the serial port.
+  /*
+   * This function opens the serial port to hold an existing native serial port.
+   *
+   * @param native_serial_port A native serial port.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void assign(const native_handle_type& native_serial_port)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().assign(impl_.get_implementation(),
+        native_serial_port, ec);
+    boost::asio::detail::throw_error(ec, "assign");
+  }
+
+  /// Assign an existing native serial port to the serial port.
+  /*
+   * This function opens the serial port to hold an existing native serial port.
+   *
+   * @param native_serial_port A native serial port.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   */
+  BOOST_ASIO_SYNC_OP_VOID assign(const native_handle_type& native_serial_port,
+      boost::system::error_code& ec)
+  {
+    impl_.get_service().assign(impl_.get_implementation(),
+        native_serial_port, ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Determine whether the serial port is open.
+  bool is_open() const
+  {
+    return impl_.get_service().is_open(impl_.get_implementation());
+  }
+
+  /// Close the serial port.
+  /**
+   * This function is used to close the serial port. Any asynchronous read or
+   * write operations will be cancelled immediately, and will complete with the
+   * boost::asio::error::operation_aborted error.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void close()
+  {
+    boost::system::error_code ec;
+    impl_.get_service().close(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "close");
+  }
+
+  /// Close the serial port.
+  /**
+   * This function is used to close the serial port. Any asynchronous read or
+   * write operations will be cancelled immediately, and will complete with the
+   * boost::asio::error::operation_aborted error.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   */
+  BOOST_ASIO_SYNC_OP_VOID close(boost::system::error_code& ec)
+  {
+    impl_.get_service().close(impl_.get_implementation(), ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Get the native serial port representation.
+  /**
+   * This function may be used to obtain the underlying representation of the
+   * serial port. This is intended to allow access to native serial port
+   * functionality that is not otherwise provided.
+   */
+  native_handle_type native_handle()
+  {
+    return impl_.get_service().native_handle(impl_.get_implementation());
+  }
+
+  /// Cancel all asynchronous operations associated with the serial port.
+  /**
+   * This function causes all outstanding asynchronous read or write operations
+   * to finish immediately, and the handlers for cancelled operations will be
+   * passed the boost::asio::error::operation_aborted error.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void cancel()
+  {
+    boost::system::error_code ec;
+    impl_.get_service().cancel(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "cancel");
+  }
+
+  /// Cancel all asynchronous operations associated with the serial port.
+  /**
+   * This function causes all outstanding asynchronous read or write operations
+   * to finish immediately, and the handlers for cancelled operations will be
+   * passed the boost::asio::error::operation_aborted error.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   */
+  BOOST_ASIO_SYNC_OP_VOID cancel(boost::system::error_code& ec)
+  {
+    impl_.get_service().cancel(impl_.get_implementation(), ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Send a break sequence to the serial port.
+  /**
+   * This function causes a break sequence of platform-specific duration to be
+   * sent out the serial port.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void send_break()
+  {
+    boost::system::error_code ec;
+    impl_.get_service().send_break(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "send_break");
+  }
+
+  /// Send a break sequence to the serial port.
+  /**
+   * This function causes a break sequence of platform-specific duration to be
+   * sent out the serial port.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   */
+  BOOST_ASIO_SYNC_OP_VOID send_break(boost::system::error_code& ec)
+  {
+    impl_.get_service().send_break(impl_.get_implementation(), ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Set an option on the serial port.
+  /**
+   * This function is used to set an option on the serial port.
+   *
+   * @param option The option value to be set on the serial port.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @sa SettableSerialPortOption @n
+   * boost::asio::serial_port_base::baud_rate @n
+   * boost::asio::serial_port_base::flow_control @n
+   * boost::asio::serial_port_base::parity @n
+   * boost::asio::serial_port_base::stop_bits @n
+   * boost::asio::serial_port_base::character_size
+   */
+  template <typename SettableSerialPortOption>
+  void set_option(const SettableSerialPortOption& option)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
+    boost::asio::detail::throw_error(ec, "set_option");
+  }
+
+  /// Set an option on the serial port.
+  /**
+   * This function is used to set an option on the serial port.
+   *
+   * @param option The option value to be set on the serial port.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @sa SettableSerialPortOption @n
+   * boost::asio::serial_port_base::baud_rate @n
+   * boost::asio::serial_port_base::flow_control @n
+   * boost::asio::serial_port_base::parity @n
+   * boost::asio::serial_port_base::stop_bits @n
+   * boost::asio::serial_port_base::character_size
+   */
+  template <typename SettableSerialPortOption>
+  BOOST_ASIO_SYNC_OP_VOID set_option(const SettableSerialPortOption& option,
+      boost::system::error_code& ec)
+  {
+    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Get an option from the serial port.
+  /**
+   * This function is used to get the current value of an option on the serial
+   * port.
+   *
+   * @param option The option value to be obtained from the serial port.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @sa GettableSerialPortOption @n
+   * boost::asio::serial_port_base::baud_rate @n
+   * boost::asio::serial_port_base::flow_control @n
+   * boost::asio::serial_port_base::parity @n
+   * boost::asio::serial_port_base::stop_bits @n
+   * boost::asio::serial_port_base::character_size
+   */
+  template <typename GettableSerialPortOption>
+  void get_option(GettableSerialPortOption& option) const
+  {
+    boost::system::error_code ec;
+    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
+    boost::asio::detail::throw_error(ec, "get_option");
+  }
+
+  /// Get an option from the serial port.
+  /**
+   * This function is used to get the current value of an option on the serial
+   * port.
+   *
+   * @param option The option value to be obtained from the serial port.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @sa GettableSerialPortOption @n
+   * boost::asio::serial_port_base::baud_rate @n
+   * boost::asio::serial_port_base::flow_control @n
+   * boost::asio::serial_port_base::parity @n
+   * boost::asio::serial_port_base::stop_bits @n
+   * boost::asio::serial_port_base::character_size
+   */
+  template <typename GettableSerialPortOption>
+  BOOST_ASIO_SYNC_OP_VOID get_option(GettableSerialPortOption& option,
+      boost::system::error_code& ec) const
+  {
+    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Write some data to the serial port.
+  /**
+   * This function is used to write data to the serial port. The function call
+   * will block until one or more bytes of the data has been written
+   * successfully, or until an error occurs.
+   *
+   * @param buffers One or more data buffers to be written to the serial port.
+   *
+   * @returns The number of bytes written.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @note The write_some operation may not transmit all of the data to the
+   * peer. Consider using the @ref write function if you need to ensure that
+   * all data is written before the blocking operation completes.
+   *
+   * @par Example
+   * To write a single data buffer use the @ref buffer function as follows:
+   * @code
+   * basic_serial_port.write_some(boost::asio::buffer(data, size));
+   * @endcode
+   * See the @ref buffer documentation for information on writing multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers)
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().write_some(
+        impl_.get_implementation(), buffers, ec);
+    boost::asio::detail::throw_error(ec, "write_some");
+    return s;
+  }
+
+  /// Write some data to the serial port.
+  /**
+   * This function is used to write data to the serial port. The function call
+   * will block until one or more bytes of the data has been written
+   * successfully, or until an error occurs.
+   *
+   * @param buffers One or more data buffers to be written to the serial port.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes written. Returns 0 if an error occurred.
+   *
+   * @note The write_some operation may not transmit all of the data to the
+   * peer. Consider using the @ref write function if you need to ensure that
+   * all data is written before the blocking operation completes.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return impl_.get_service().write_some(
+        impl_.get_implementation(), buffers, ec);
+  }
+
+  /// Start an asynchronous write.
+  /**
+   * This function is used to asynchronously write data to the serial port.
+   * The function call always returns immediately.
+   *
+   * @param buffers One or more data buffers to be written to the serial port.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param handler The handler to be called when the write operation completes.
+   * Copies will be made of the handler as required. The function signature of
+   * the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes written.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The write operation may not transmit all of the data to the peer.
+   * Consider using the @ref async_write function if you need to ensure that all
+   * data is written before the asynchronous operation completes.
+   *
+   * @par Example
+   * To write a single data buffer use the @ref buffer function as follows:
+   * @code
+   * basic_serial_port.async_write_some(
+   *     boost::asio::buffer(data, size), handler);
+   * @endcode
+   * See the @ref buffer documentation for information on writing multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_write_some(const ConstBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return async_initiate<WriteHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_write_some(), handler, this, buffers);
+  }
+
+  /// Read some data from the serial port.
+  /**
+   * This function is used to read data from the serial port. The function
+   * call will block until one or more bytes of data has been read successfully,
+   * or until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be read.
+   *
+   * @returns The number of bytes read.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @note The read_some operation may not read all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that
+   * the requested amount of data is read before the blocking operation
+   * completes.
+   *
+   * @par Example
+   * To read into a single data buffer use the @ref buffer function as follows:
+   * @code
+   * basic_serial_port.read_some(boost::asio::buffer(data, size));
+   * @endcode
+   * See the @ref buffer documentation for information on reading into multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers)
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().read_some(
+        impl_.get_implementation(), buffers, ec);
+    boost::asio::detail::throw_error(ec, "read_some");
+    return s;
+  }
+
+  /// Read some data from the serial port.
+  /**
+   * This function is used to read data from the serial port. The function
+   * call will block until one or more bytes of data has been read successfully,
+   * or until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be read.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes read. Returns 0 if an error occurred.
+   *
+   * @note The read_some operation may not read all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that
+   * the requested amount of data is read before the blocking operation
+   * completes.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return impl_.get_service().read_some(
+        impl_.get_implementation(), buffers, ec);
+  }
+
+  /// Start an asynchronous read.
+  /**
+   * This function is used to asynchronously read data from the serial port.
+   * The function call always returns immediately.
+   *
+   * @param buffers One or more buffers into which the data will be read.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param handler The handler to be called when the read operation completes.
+   * Copies will be made of the handler as required. The function signature of
+   * the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes read.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The read operation may not read all of the requested number of bytes.
+   * Consider using the @ref async_read function if you need to ensure that the
+   * requested amount of data is read before the asynchronous operation
+   * completes.
+   *
+   * @par Example
+   * To read into a single data buffer use the @ref buffer function as follows:
+   * @code
+   * basic_serial_port.async_read_some(
+   *     boost::asio::buffer(data, size), handler);
+   * @endcode
+   * See the @ref buffer documentation for information on reading into multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_read_some(const MutableBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return async_initiate<ReadHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_read_some(), handler, this, buffers);
+  }
+
+private:
+  // Disallow copying and assignment.
+  basic_serial_port(const basic_serial_port&) BOOST_ASIO_DELETED;
+  basic_serial_port& operator=(const basic_serial_port&) BOOST_ASIO_DELETED;
+
+  struct initiate_async_write_some
+  {
+    template <typename WriteHandler, typename ConstBufferSequence>
+    void operator()(BOOST_ASIO_MOVE_ARG(WriteHandler) handler,
+        basic_serial_port* self, const ConstBufferSequence& buffers) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a WriteHandler.
+      BOOST_ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
+
+      detail::non_const_lvalue<WriteHandler> handler2(handler);
+      self->impl_.get_service().async_write_some(
+          self->impl_.get_implementation(), buffers, handler2.value,
+          self->impl_.get_implementation_executor());
+    }
+  };
+
+  struct initiate_async_read_some
+  {
+    template <typename ReadHandler, typename MutableBufferSequence>
+    void operator()(BOOST_ASIO_MOVE_ARG(ReadHandler) handler,
+        basic_serial_port* self, const MutableBufferSequence& buffers) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a ReadHandler.
+      BOOST_ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
+
+      detail::non_const_lvalue<ReadHandler> handler2(handler);
+      self->impl_.get_service().async_read_some(
+          self->impl_.get_implementation(), buffers, handler2.value,
+          self->impl_.get_implementation_executor());
+    }
+  };
+
+#if defined(BOOST_ASIO_HAS_IOCP)
+  detail::io_object_impl<detail::win_iocp_serial_port_service, Executor> impl_;
+#else
+  detail::io_object_impl<detail::reactive_serial_port_service, Executor> impl_;
+#endif
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(BOOST_ASIO_HAS_SERIAL_PORT)
+       //   || defined(GENERATING_DOCUMENTATION)
+
+#endif // BOOST_ASIO_BASIC_SERIAL_PORT_HPP

boost/asio/basic_signal_set.hpp

@@ -0,0 +1,543 @@
+//
+// basic_signal_set.hpp
+// ~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_SIGNAL_SET_HPP
+#define BOOST_ASIO_BASIC_SIGNAL_SET_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/detail/handler_type_requirements.hpp>
+#include <boost/asio/detail/io_object_impl.hpp>
+#include <boost/asio/detail/non_const_lvalue.hpp>
+#include <boost/asio/detail/signal_set_service.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/executor.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Provides signal functionality.
+/**
+ * The basic_signal_set class provides the ability to perform an asynchronous
+ * wait for one or more signals to occur.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ *
+ * @par Example
+ * Performing an asynchronous wait:
+ * @code
+ * void handler(
+ *     const boost::system::error_code& error,
+ *     int signal_number)
+ * {
+ *   if (!error)
+ *   {
+ *     // A signal occurred.
+ *   }
+ * }
+ *
+ * ...
+ *
+ * // Construct a signal set registered for process termination.
+ * boost::asio::signal_set signals(my_context, SIGINT, SIGTERM);
+ *
+ * // Start an asynchronous wait for one of the signals to occur.
+ * signals.async_wait(handler);
+ * @endcode
+ *
+ * @par Queueing of signal notifications
+ *
+ * If a signal is registered with a signal_set, and the signal occurs when
+ * there are no waiting handlers, then the signal notification is queued. The
+ * next async_wait operation on that signal_set will dequeue the notification.
+ * If multiple notifications are queued, subsequent async_wait operations
+ * dequeue them one at a time. Signal notifications are dequeued in order of
+ * ascending signal number.
+ *
+ * If a signal number is removed from a signal_set (using the @c remove or @c
+ * erase member functions) then any queued notifications for that signal are
+ * discarded.
+ *
+ * @par Multiple registration of signals
+ *
+ * The same signal number may be registered with different signal_set objects.
+ * When the signal occurs, one handler is called for each signal_set object.
+ *
+ * Note that multiple registration only works for signals that are registered
+ * using Asio. The application must not also register a signal handler using
+ * functions such as @c signal() or @c sigaction().
+ *
+ * @par Signal masking on POSIX platforms
+ *
+ * POSIX allows signals to be blocked using functions such as @c sigprocmask()
+ * and @c pthread_sigmask(). For signals to be delivered, programs must ensure
+ * that any signals registered using signal_set objects are unblocked in at
+ * least one thread.
+ */
+template <typename Executor = executor>
+class basic_signal_set
+{
+public:
+  /// The type of the executor associated with the object.
+  typedef Executor executor_type;
+
+  /// Construct a signal set without adding any signals.
+  /**
+   * This constructor creates a signal set without registering for any signals.
+   *
+   * @param ex The I/O executor that the signal set will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * signal set.
+   */
+  explicit basic_signal_set(const executor_type& ex)
+    : impl_(ex)
+  {
+  }
+
+  /// Construct a signal set without adding any signals.
+  /**
+   * This constructor creates a signal set without registering for any signals.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the signal set will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the signal set.
+   */
+  template <typename ExecutionContext>
+  explicit basic_signal_set(ExecutionContext& context,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+  }
+
+  /// Construct a signal set and add one signal.
+  /**
+   * This constructor creates a signal set and registers for one signal.
+   *
+   * @param ex The I/O executor that the signal set will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * signal set.
+   *
+   * @param signal_number_1 The signal number to be added.
+   *
+   * @note This constructor is equivalent to performing:
+   * @code boost::asio::signal_set signals(ex);
+   * signals.add(signal_number_1); @endcode
+   */
+  basic_signal_set(const executor_type& ex, int signal_number_1)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
+    boost::asio::detail::throw_error(ec, "add");
+  }
+
+  /// Construct a signal set and add one signal.
+  /**
+   * This constructor creates a signal set and registers for one signal.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the signal set will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the signal set.
+   *
+   * @param signal_number_1 The signal number to be added.
+   *
+   * @note This constructor is equivalent to performing:
+   * @code boost::asio::signal_set signals(context);
+   * signals.add(signal_number_1); @endcode
+   */
+  template <typename ExecutionContext>
+  basic_signal_set(ExecutionContext& context, int signal_number_1,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
+    boost::asio::detail::throw_error(ec, "add");
+  }
+
+  /// Construct a signal set and add two signals.
+  /**
+   * This constructor creates a signal set and registers for two signals.
+   *
+   * @param ex The I/O executor that the signal set will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * signal set.
+   *
+   * @param signal_number_1 The first signal number to be added.
+   *
+   * @param signal_number_2 The second signal number to be added.
+   *
+   * @note This constructor is equivalent to performing:
+   * @code boost::asio::signal_set signals(ex);
+   * signals.add(signal_number_1);
+   * signals.add(signal_number_2); @endcode
+   */
+  basic_signal_set(const executor_type& ex, int signal_number_1,
+      int signal_number_2)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
+    boost::asio::detail::throw_error(ec, "add");
+    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
+    boost::asio::detail::throw_error(ec, "add");
+  }
+
+  /// Construct a signal set and add two signals.
+  /**
+   * This constructor creates a signal set and registers for two signals.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the signal set will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the signal set.
+   *
+   * @param signal_number_1 The first signal number to be added.
+   *
+   * @param signal_number_2 The second signal number to be added.
+   *
+   * @note This constructor is equivalent to performing:
+   * @code boost::asio::signal_set signals(context);
+   * signals.add(signal_number_1);
+   * signals.add(signal_number_2); @endcode
+   */
+  template <typename ExecutionContext>
+  basic_signal_set(ExecutionContext& context, int signal_number_1,
+      int signal_number_2,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
+    boost::asio::detail::throw_error(ec, "add");
+    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
+    boost::asio::detail::throw_error(ec, "add");
+  }
+
+  /// Construct a signal set and add three signals.
+  /**
+   * This constructor creates a signal set and registers for three signals.
+   *
+   * @param ex The I/O executor that the signal set will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the
+   * signal set.
+   *
+   * @param signal_number_1 The first signal number to be added.
+   *
+   * @param signal_number_2 The second signal number to be added.
+   *
+   * @param signal_number_3 The third signal number to be added.
+   *
+   * @note This constructor is equivalent to performing:
+   * @code boost::asio::signal_set signals(ex);
+   * signals.add(signal_number_1);
+   * signals.add(signal_number_2);
+   * signals.add(signal_number_3); @endcode
+   */
+  basic_signal_set(const executor_type& ex, int signal_number_1,
+      int signal_number_2, int signal_number_3)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
+    boost::asio::detail::throw_error(ec, "add");
+    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
+    boost::asio::detail::throw_error(ec, "add");
+    impl_.get_service().add(impl_.get_implementation(), signal_number_3, ec);
+    boost::asio::detail::throw_error(ec, "add");
+  }
+
+  /// Construct a signal set and add three signals.
+  /**
+   * This constructor creates a signal set and registers for three signals.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the signal set will use, by default, to dispatch handlers for any
+   * asynchronous operations performed on the signal set.
+   *
+   * @param signal_number_1 The first signal number to be added.
+   *
+   * @param signal_number_2 The second signal number to be added.
+   *
+   * @param signal_number_3 The third signal number to be added.
+   *
+   * @note This constructor is equivalent to performing:
+   * @code boost::asio::signal_set signals(context);
+   * signals.add(signal_number_1);
+   * signals.add(signal_number_2);
+   * signals.add(signal_number_3); @endcode
+   */
+  template <typename ExecutionContext>
+  basic_signal_set(ExecutionContext& context, int signal_number_1,
+      int signal_number_2, int signal_number_3,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
+    boost::asio::detail::throw_error(ec, "add");
+    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
+    boost::asio::detail::throw_error(ec, "add");
+    impl_.get_service().add(impl_.get_implementation(), signal_number_3, ec);
+    boost::asio::detail::throw_error(ec, "add");
+  }
+
+  /// Destroys the signal set.
+  /**
+   * This function destroys the signal set, cancelling any outstanding
+   * asynchronous wait operations associated with the signal set as if by
+   * calling @c cancel.
+   */
+  ~basic_signal_set()
+  {
+  }
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return impl_.get_executor();
+  }
+
+  /// Add a signal to a signal_set.
+  /**
+   * This function adds the specified signal to the set. It has no effect if the
+   * signal is already in the set.
+   *
+   * @param signal_number The signal to be added to the set.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void add(int signal_number)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().add(impl_.get_implementation(), signal_number, ec);
+    boost::asio::detail::throw_error(ec, "add");
+  }
+
+  /// Add a signal to a signal_set.
+  /**
+   * This function adds the specified signal to the set. It has no effect if the
+   * signal is already in the set.
+   *
+   * @param signal_number The signal to be added to the set.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   */
+  BOOST_ASIO_SYNC_OP_VOID add(int signal_number,
+      boost::system::error_code& ec)
+  {
+    impl_.get_service().add(impl_.get_implementation(), signal_number, ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Remove a signal from a signal_set.
+  /**
+   * This function removes the specified signal from the set. It has no effect
+   * if the signal is not in the set.
+   *
+   * @param signal_number The signal to be removed from the set.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note Removes any notifications that have been queued for the specified
+   * signal number.
+   */
+  void remove(int signal_number)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().remove(impl_.get_implementation(), signal_number, ec);
+    boost::asio::detail::throw_error(ec, "remove");
+  }
+
+  /// Remove a signal from a signal_set.
+  /**
+   * This function removes the specified signal from the set. It has no effect
+   * if the signal is not in the set.
+   *
+   * @param signal_number The signal to be removed from the set.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @note Removes any notifications that have been queued for the specified
+   * signal number.
+   */
+  BOOST_ASIO_SYNC_OP_VOID remove(int signal_number,
+      boost::system::error_code& ec)
+  {
+    impl_.get_service().remove(impl_.get_implementation(), signal_number, ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Remove all signals from a signal_set.
+  /**
+   * This function removes all signals from the set. It has no effect if the set
+   * is already empty.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note Removes all queued notifications.
+   */
+  void clear()
+  {
+    boost::system::error_code ec;
+    impl_.get_service().clear(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "clear");
+  }
+
+  /// Remove all signals from a signal_set.
+  /**
+   * This function removes all signals from the set. It has no effect if the set
+   * is already empty.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @note Removes all queued notifications.
+   */
+  BOOST_ASIO_SYNC_OP_VOID clear(boost::system::error_code& ec)
+  {
+    impl_.get_service().clear(impl_.get_implementation(), ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Cancel all operations associated with the signal set.
+  /**
+   * This function forces the completion of any pending asynchronous wait
+   * operations against the signal set. The handler for each cancelled
+   * operation will be invoked with the boost::asio::error::operation_aborted
+   * error code.
+   *
+   * Cancellation does not alter the set of registered signals.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If a registered signal occurred before cancel() is called, then the
+   * handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  void cancel()
+  {
+    boost::system::error_code ec;
+    impl_.get_service().cancel(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "cancel");
+  }
+
+  /// Cancel all operations associated with the signal set.
+  /**
+   * This function forces the completion of any pending asynchronous wait
+   * operations against the signal set. The handler for each cancelled
+   * operation will be invoked with the boost::asio::error::operation_aborted
+   * error code.
+   *
+   * Cancellation does not alter the set of registered signals.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @note If a registered signal occurred before cancel() is called, then the
+   * handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  BOOST_ASIO_SYNC_OP_VOID cancel(boost::system::error_code& ec)
+  {
+    impl_.get_service().cancel(impl_.get_implementation(), ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Start an asynchronous operation to wait for a signal to be delivered.
+  /**
+   * This function may be used to initiate an asynchronous wait against the
+   * signal set. It always returns immediately.
+   *
+   * For each call to async_wait(), the supplied handler will be called exactly
+   * once. The handler will be called when:
+   *
+   * @li One of the registered signals in the signal set occurs; or
+   *
+   * @li The signal set was cancelled, in which case the handler is passed the
+   * error code boost::asio::error::operation_aborted.
+   *
+   * @param handler The handler to be called when the signal occurs. Copies
+   * will be made of the handler as required. The function signature of the
+   * handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   int signal_number // Indicates which signal occurred.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   */
+  template <typename SignalHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(SignalHandler,
+      void (boost::system::error_code, int))
+  async_wait(BOOST_ASIO_MOVE_ARG(SignalHandler) handler)
+  {
+    return async_initiate<SignalHandler, void (boost::system::error_code, int)>(
+        initiate_async_wait(), handler, this);
+  }
+
+private:
+  // Disallow copying and assignment.
+  basic_signal_set(const basic_signal_set&) BOOST_ASIO_DELETED;
+  basic_signal_set& operator=(const basic_signal_set&) BOOST_ASIO_DELETED;
+
+  struct initiate_async_wait
+  {
+    template <typename SignalHandler>
+    void operator()(BOOST_ASIO_MOVE_ARG(SignalHandler) handler,
+        basic_signal_set* self) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a SignalHandler.
+      BOOST_ASIO_SIGNAL_HANDLER_CHECK(SignalHandler, handler) type_check;
+
+      detail::non_const_lvalue<SignalHandler> handler2(handler);
+      self->impl_.get_service().async_wait(
+          self->impl_.get_implementation(), handler2.value,
+          self->impl_.get_implementation_executor());
+    }
+  };
+
+  detail::io_object_impl<detail::signal_set_service, Executor> impl_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_BASIC_SIGNAL_SET_HPP

boost/asio/basic_socket_iostream.hpp

@@ -0,0 +1,409 @@
+//
+// basic_socket_iostream.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_SOCKET_IOSTREAM_HPP
+#define BOOST_ASIO_BASIC_SOCKET_IOSTREAM_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#include <istream>
+#include <ostream>
+#include <boost/asio/basic_socket_streambuf.hpp>
+
+#if !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+# include <boost/asio/detail/variadic_templates.hpp>
+
+// A macro that should expand to:
+//   template <typename T1, ..., typename Tn>
+//   explicit basic_socket_iostream(T1 x1, ..., Tn xn)
+//     : std::basic_iostream<char>(
+//         &this->detail::socket_iostream_base<
+//           Protocol, Clock, WaitTraits>::streambuf_)
+//   {
+//     if (rdbuf()->connect(x1, ..., xn) == 0)
+//       this->setstate(std::ios_base::failbit);
+//   }
+// This macro should only persist within this file.
+
+# define BOOST_ASIO_PRIVATE_CTR_DEF(n) \
+  template <BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  explicit basic_socket_iostream(BOOST_ASIO_VARIADIC_BYVAL_PARAMS(n)) \
+    : std::basic_iostream<char>( \
+        &this->detail::socket_iostream_base< \
+          Protocol, Clock, WaitTraits>::streambuf_) \
+  { \
+    this->setf(std::ios_base::unitbuf); \
+    if (rdbuf()->connect(BOOST_ASIO_VARIADIC_BYVAL_ARGS(n)) == 0) \
+      this->setstate(std::ios_base::failbit); \
+  } \
+  /**/
+
+// A macro that should expand to:
+//   template <typename T1, ..., typename Tn>
+//   void connect(T1 x1, ..., Tn xn)
+//   {
+//     if (rdbuf()->connect(x1, ..., xn) == 0)
+//       this->setstate(std::ios_base::failbit);
+//   }
+// This macro should only persist within this file.
+
+# define BOOST_ASIO_PRIVATE_CONNECT_DEF(n) \
+  template <BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  void connect(BOOST_ASIO_VARIADIC_BYVAL_PARAMS(n)) \
+  { \
+    if (rdbuf()->connect(BOOST_ASIO_VARIADIC_BYVAL_ARGS(n)) == 0) \
+      this->setstate(std::ios_base::failbit); \
+  } \
+  /**/
+
+#endif // !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// A separate base class is used to ensure that the streambuf is initialised
+// prior to the basic_socket_iostream's basic_iostream base class.
+template <typename Protocol, typename Clock, typename WaitTraits>
+class socket_iostream_base
+{
+protected:
+  socket_iostream_base()
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+  socket_iostream_base(socket_iostream_base&& other)
+    : streambuf_(std::move(other.streambuf_))
+  {
+  }
+
+  socket_iostream_base(basic_stream_socket<Protocol> s)
+    : streambuf_(std::move(s))
+  {
+  }
+
+  socket_iostream_base& operator=(socket_iostream_base&& other)
+  {
+    streambuf_ = std::move(other.streambuf_);
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+  basic_socket_streambuf<Protocol, Clock, WaitTraits> streambuf_;
+};
+
+} // namespace detail
+
+#if !defined(BOOST_ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL)
+#define BOOST_ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL
+
+// Forward declaration with defaulted arguments.
+template <typename Protocol,
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+    typename Clock = boost::posix_time::ptime,
+    typename WaitTraits = time_traits<Clock> >
+#else // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+      // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+    typename Clock = chrono::steady_clock,
+    typename WaitTraits = wait_traits<Clock> >
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+class basic_socket_iostream;
+
+#endif // !defined(BOOST_ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL)
+
+/// Iostream interface for a socket.
+#if defined(GENERATING_DOCUMENTATION)
+template <typename Protocol,
+    typename Clock = chrono::steady_clock,
+    typename WaitTraits = wait_traits<Clock> >
+#else // defined(GENERATING_DOCUMENTATION)
+template <typename Protocol, typename Clock, typename WaitTraits>
+#endif // defined(GENERATING_DOCUMENTATION)
+class basic_socket_iostream
+  : private detail::socket_iostream_base<Protocol, Clock, WaitTraits>,
+    public std::basic_iostream<char>
+{
+private:
+  // These typedefs are intended keep this class's implementation independent
+  // of whether it's using Boost.DateClock, Boost.Chrono or std::chrono.
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+  typedef WaitTraits traits_helper;
+#else // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+      // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+  typedef detail::chrono_time_traits<Clock, WaitTraits> traits_helper;
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+
+public:
+  /// The protocol type.
+  typedef Protocol protocol_type;
+
+  /// The endpoint type.
+  typedef typename Protocol::endpoint endpoint_type;
+
+  /// The clock type.
+  typedef Clock clock_type;
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// (Deprecated: Use time_point.) The time type.
+  typedef typename WaitTraits::time_type time_type;
+
+  /// The time type.
+  typedef typename WaitTraits::time_point time_point;
+
+  /// (Deprecated: Use duration.) The duration type.
+  typedef typename WaitTraits::duration_type duration_type;
+
+  /// The duration type.
+  typedef typename WaitTraits::duration duration;
+#else
+# if !defined(BOOST_ASIO_NO_DEPRECATED)
+  typedef typename traits_helper::time_type time_type;
+  typedef typename traits_helper::duration_type duration_type;
+# endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+  typedef typename traits_helper::time_type time_point;
+  typedef typename traits_helper::duration_type duration;
+#endif
+
+  /// Construct a basic_socket_iostream without establishing a connection.
+  basic_socket_iostream()
+    : std::basic_iostream<char>(
+        &this->detail::socket_iostream_base<
+          Protocol, Clock, WaitTraits>::streambuf_)
+  {
+    this->setf(std::ios_base::unitbuf);
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Construct a basic_socket_iostream from the supplied socket.
+  explicit basic_socket_iostream(basic_stream_socket<protocol_type> s)
+    : detail::socket_iostream_base<
+        Protocol, Clock, WaitTraits>(std::move(s)),
+      std::basic_iostream<char>(
+        &this->detail::socket_iostream_base<
+          Protocol, Clock, WaitTraits>::streambuf_)
+  {
+    this->setf(std::ios_base::unitbuf);
+  }
+
+#if defined(BOOST_ASIO_HAS_STD_IOSTREAM_MOVE) \
+  || defined(GENERATING_DOCUMENTATION)
+  /// Move-construct a basic_socket_iostream from another.
+  basic_socket_iostream(basic_socket_iostream&& other)
+    : detail::socket_iostream_base<
+        Protocol, Clock, WaitTraits>(std::move(other)),
+      std::basic_iostream<char>(std::move(other))
+  {
+    this->set_rdbuf(&this->detail::socket_iostream_base<
+          Protocol, Clock, WaitTraits>::streambuf_);
+  }
+
+  /// Move-assign a basic_socket_iostream from another.
+  basic_socket_iostream& operator=(basic_socket_iostream&& other)
+  {
+    std::basic_iostream<char>::operator=(std::move(other));
+    detail::socket_iostream_base<
+        Protocol, Clock, WaitTraits>::operator=(std::move(other));
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_STD_IOSTREAM_MOVE)
+       //   || defined(GENERATING_DOCUMENTATION)
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// Establish a connection to an endpoint corresponding to a resolver query.
+  /**
+   * This constructor automatically establishes a connection based on the
+   * supplied resolver query parameters. The arguments are used to construct
+   * a resolver query object.
+   */
+  template <typename T1, ..., typename TN>
+  explicit basic_socket_iostream(T1 t1, ..., TN tn);
+#elif defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+  template <typename... T>
+  explicit basic_socket_iostream(T... x)
+    : std::basic_iostream<char>(
+        &this->detail::socket_iostream_base<
+          Protocol, Clock, WaitTraits>::streambuf_)
+  {
+    this->setf(std::ios_base::unitbuf);
+    if (rdbuf()->connect(x...) == 0)
+      this->setstate(std::ios_base::failbit);
+  }
+#else
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_CTR_DEF)
+#endif
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// Establish a connection to an endpoint corresponding to a resolver query.
+  /**
+   * This function automatically establishes a connection based on the supplied
+   * resolver query parameters. The arguments are used to construct a resolver
+   * query object.
+   */
+  template <typename T1, ..., typename TN>
+  void connect(T1 t1, ..., TN tn);
+#elif defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+  template <typename... T>
+  void connect(T... x)
+  {
+    if (rdbuf()->connect(x...) == 0)
+      this->setstate(std::ios_base::failbit);
+  }
+#else
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_CONNECT_DEF)
+#endif
+
+  /// Close the connection.
+  void close()
+  {
+    if (rdbuf()->close() == 0)
+      this->setstate(std::ios_base::failbit);
+  }
+
+  /// Return a pointer to the underlying streambuf.
+  basic_socket_streambuf<Protocol, Clock, WaitTraits>* rdbuf() const
+  {
+    return const_cast<basic_socket_streambuf<Protocol, Clock, WaitTraits>*>(
+        &this->detail::socket_iostream_base<
+          Protocol, Clock, WaitTraits>::streambuf_);
+  }
+
+  /// Get a reference to the underlying socket.
+  basic_socket<Protocol>& socket()
+  {
+    return rdbuf()->socket();
+  }
+
+  /// Get the last error associated with the stream.
+  /**
+   * @return An \c error_code corresponding to the last error from the stream.
+   *
+   * @par Example
+   * To print the error associated with a failure to establish a connection:
+   * @code tcp::iostream s("www.boost.org", "http");
+   * if (!s)
+   * {
+   *   std::cout << "Error: " << s.error().message() << std::endl;
+   * } @endcode
+   */
+  const boost::system::error_code& error() const
+  {
+    return rdbuf()->error();
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use expiry().) Get the stream's expiry time as an absolute
+  /// time.
+  /**
+   * @return An absolute time value representing the stream's expiry time.
+   */
+  time_point expires_at() const
+  {
+    return rdbuf()->expires_at();
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  /// Get the stream's expiry time as an absolute time.
+  /**
+   * @return An absolute time value representing the stream's expiry time.
+   */
+  time_point expiry() const
+  {
+    return rdbuf()->expiry();
+  }
+
+  /// Set the stream's expiry time as an absolute time.
+  /**
+   * This function sets the expiry time associated with the stream. Stream
+   * operations performed after this time (where the operations cannot be
+   * completed using the internal buffers) will fail with the error
+   * boost::asio::error::operation_aborted.
+   *
+   * @param expiry_time The expiry time to be used for the stream.
+   */
+  void expires_at(const time_point& expiry_time)
+  {
+    rdbuf()->expires_at(expiry_time);
+  }
+
+  /// Set the stream's expiry time relative to now.
+  /**
+   * This function sets the expiry time associated with the stream. Stream
+   * operations performed after this time (where the operations cannot be
+   * completed using the internal buffers) will fail with the error
+   * boost::asio::error::operation_aborted.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   */
+  void expires_after(const duration& expiry_time)
+  {
+    rdbuf()->expires_after(expiry_time);
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use expiry().) Get the stream's expiry time relative to now.
+  /**
+   * @return A relative time value representing the stream's expiry time.
+   */
+  duration expires_from_now() const
+  {
+    return rdbuf()->expires_from_now();
+  }
+
+  /// (Deprecated: Use expires_after().) Set the stream's expiry time relative
+  /// to now.
+  /**
+   * This function sets the expiry time associated with the stream. Stream
+   * operations performed after this time (where the operations cannot be
+   * completed using the internal buffers) will fail with the error
+   * boost::asio::error::operation_aborted.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   */
+  void expires_from_now(const duration& expiry_time)
+  {
+    rdbuf()->expires_from_now(expiry_time);
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+private:
+  // Disallow copying and assignment.
+  basic_socket_iostream(const basic_socket_iostream&) BOOST_ASIO_DELETED;
+  basic_socket_iostream& operator=(
+      const basic_socket_iostream&) BOOST_ASIO_DELETED;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#if !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+# undef BOOST_ASIO_PRIVATE_CTR_DEF
+# undef BOOST_ASIO_PRIVATE_CONNECT_DEF
+#endif // !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#endif // BOOST_ASIO_BASIC_SOCKET_IOSTREAM_HPP

boost/asio/basic_socket_streambuf.hpp

@@ -0,0 +1,689 @@
+//
+// basic_socket_streambuf.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_SOCKET_STREAMBUF_HPP
+#define BOOST_ASIO_BASIC_SOCKET_STREAMBUF_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#include <streambuf>
+#include <vector>
+#include <boost/asio/basic_socket.hpp>
+#include <boost/asio/basic_stream_socket.hpp>
+#include <boost/asio/detail/buffer_sequence_adapter.hpp>
+#include <boost/asio/detail/memory.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+#include <boost/asio/io_context.hpp>
+
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+# include <boost/asio/detail/deadline_timer_service.hpp>
+#else // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+      // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+# include <boost/asio/steady_timer.hpp>
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+
+#if !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+# include <boost/asio/detail/variadic_templates.hpp>
+
+// A macro that should expand to:
+//   template <typename T1, ..., typename Tn>
+//   basic_socket_streambuf* connect(T1 x1, ..., Tn xn)
+//   {
+//     init_buffers();
+//     typedef typename Protocol::resolver resolver_type;
+//     resolver_type resolver(socket().get_executor());
+//     connect_to_endpoints(
+//         resolver.resolve(x1, ..., xn, ec_));
+//     return !ec_ ? this : 0;
+//   }
+// This macro should only persist within this file.
+
+# define BOOST_ASIO_PRIVATE_CONNECT_DEF(n) \
+  template <BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  basic_socket_streambuf* connect(BOOST_ASIO_VARIADIC_BYVAL_PARAMS(n)) \
+  { \
+    init_buffers(); \
+    typedef typename Protocol::resolver resolver_type; \
+    resolver_type resolver(socket().get_executor()); \
+    connect_to_endpoints( \
+        resolver.resolve(BOOST_ASIO_VARIADIC_BYVAL_ARGS(n), ec_)); \
+    return !ec_ ? this : 0; \
+  } \
+  /**/
+
+#endif // !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// A separate base class is used to ensure that the io_context member is
+// initialised prior to the basic_socket_streambuf's basic_socket base class.
+class socket_streambuf_io_context
+{
+protected:
+  socket_streambuf_io_context(io_context* ctx)
+    : default_io_context_(ctx)
+  {
+  }
+
+  shared_ptr<io_context> default_io_context_;
+};
+
+// A separate base class is used to ensure that the dynamically allocated
+// buffers are constructed prior to the basic_socket_streambuf's basic_socket
+// base class. This makes moving the socket is the last potentially throwing
+// step in the streambuf's move constructor, giving the constructor a strong
+// exception safety guarantee.
+class socket_streambuf_buffers
+{
+protected:
+  socket_streambuf_buffers()
+    : get_buffer_(buffer_size),
+      put_buffer_(buffer_size)
+  {
+  }
+
+  enum { buffer_size = 512 };
+  std::vector<char> get_buffer_;
+  std::vector<char> put_buffer_;
+};
+
+} // namespace detail
+
+#if !defined(BOOST_ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL)
+#define BOOST_ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL
+
+// Forward declaration with defaulted arguments.
+template <typename Protocol,
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+    typename Clock = boost::posix_time::ptime,
+    typename WaitTraits = time_traits<Clock> >
+#else // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+      // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+    typename Clock = chrono::steady_clock,
+    typename WaitTraits = wait_traits<Clock> >
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+class basic_socket_streambuf;
+
+#endif // !defined(BOOST_ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL)
+
+/// Iostream streambuf for a socket.
+#if defined(GENERATING_DOCUMENTATION)
+template <typename Protocol,
+    typename Clock = chrono::steady_clock,
+    typename WaitTraits = wait_traits<Clock> >
+#else // defined(GENERATING_DOCUMENTATION)
+template <typename Protocol, typename Clock, typename WaitTraits>
+#endif // defined(GENERATING_DOCUMENTATION)
+class basic_socket_streambuf
+  : public std::streambuf,
+    private detail::socket_streambuf_io_context,
+    private detail::socket_streambuf_buffers,
+#if defined(BOOST_ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
+    private basic_socket<Protocol>
+#else // defined(BOOST_ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
+    public basic_socket<Protocol>
+#endif // defined(BOOST_ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
+{
+private:
+  // These typedefs are intended keep this class's implementation independent
+  // of whether it's using Boost.DateClock, Boost.Chrono or std::chrono.
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+  typedef WaitTraits traits_helper;
+#else // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+      // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+  typedef detail::chrono_time_traits<Clock, WaitTraits> traits_helper;
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+
+public:
+  /// The protocol type.
+  typedef Protocol protocol_type;
+
+  /// The endpoint type.
+  typedef typename Protocol::endpoint endpoint_type;
+
+  /// The clock type.
+  typedef Clock clock_type;
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// (Deprecated: Use time_point.) The time type.
+  typedef typename WaitTraits::time_type time_type;
+
+  /// The time type.
+  typedef typename WaitTraits::time_point time_point;
+
+  /// (Deprecated: Use duration.) The duration type.
+  typedef typename WaitTraits::duration_type duration_type;
+
+  /// The duration type.
+  typedef typename WaitTraits::duration duration;
+#else
+# if !defined(BOOST_ASIO_NO_DEPRECATED)
+  typedef typename traits_helper::time_type time_type;
+  typedef typename traits_helper::duration_type duration_type;
+# endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+  typedef typename traits_helper::time_type time_point;
+  typedef typename traits_helper::duration_type duration;
+#endif
+
+  /// Construct a basic_socket_streambuf without establishing a connection.
+  basic_socket_streambuf()
+    : detail::socket_streambuf_io_context(new io_context),
+      basic_socket<Protocol>(*default_io_context_),
+      expiry_time_(max_expiry_time())
+  {
+    init_buffers();
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Construct a basic_socket_streambuf from the supplied socket.
+  explicit basic_socket_streambuf(basic_stream_socket<protocol_type> s)
+    : detail::socket_streambuf_io_context(0),
+      basic_socket<Protocol>(std::move(s)),
+      expiry_time_(max_expiry_time())
+  {
+    init_buffers();
+  }
+
+  /// Move-construct a basic_socket_streambuf from another.
+  basic_socket_streambuf(basic_socket_streambuf&& other)
+    : detail::socket_streambuf_io_context(other),
+      basic_socket<Protocol>(std::move(other.socket())),
+      ec_(other.ec_),
+      expiry_time_(other.expiry_time_)
+  {
+    get_buffer_.swap(other.get_buffer_);
+    put_buffer_.swap(other.put_buffer_);
+    setg(other.eback(), other.gptr(), other.egptr());
+    setp(other.pptr(), other.epptr());
+    other.ec_ = boost::system::error_code();
+    other.expiry_time_ = max_expiry_time();
+    other.init_buffers();
+  }
+
+  /// Move-assign a basic_socket_streambuf from another.
+  basic_socket_streambuf& operator=(basic_socket_streambuf&& other)
+  {
+    this->close();
+    socket() = std::move(other.socket());
+    detail::socket_streambuf_io_context::operator=(other);
+    ec_ = other.ec_;
+    expiry_time_ = other.expiry_time_;
+    get_buffer_.swap(other.get_buffer_);
+    put_buffer_.swap(other.put_buffer_);
+    setg(other.eback(), other.gptr(), other.egptr());
+    setp(other.pptr(), other.epptr());
+    other.ec_ = boost::system::error_code();
+    other.expiry_time_ = max_expiry_time();
+    other.put_buffer_.resize(buffer_size);
+    other.init_buffers();
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Destructor flushes buffered data.
+  virtual ~basic_socket_streambuf()
+  {
+    if (pptr() != pbase())
+      overflow(traits_type::eof());
+  }
+
+  /// Establish a connection.
+  /**
+   * This function establishes a connection to the specified endpoint.
+   *
+   * @return \c this if a connection was successfully established, a null
+   * pointer otherwise.
+   */
+  basic_socket_streambuf* connect(const endpoint_type& endpoint)
+  {
+    init_buffers();
+    ec_ = boost::system::error_code();
+    this->connect_to_endpoints(&endpoint, &endpoint + 1);
+    return !ec_ ? this : 0;
+  }
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// Establish a connection.
+  /**
+   * This function automatically establishes a connection based on the supplied
+   * resolver query parameters. The arguments are used to construct a resolver
+   * query object.
+   *
+   * @return \c this if a connection was successfully established, a null
+   * pointer otherwise.
+   */
+  template <typename T1, ..., typename TN>
+  basic_socket_streambuf* connect(T1 t1, ..., TN tn);
+#elif defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+  template <typename... T>
+  basic_socket_streambuf* connect(T... x)
+  {
+    init_buffers();
+    typedef typename Protocol::resolver resolver_type;
+    resolver_type resolver(socket().get_executor());
+    connect_to_endpoints(resolver.resolve(x..., ec_));
+    return !ec_ ? this : 0;
+  }
+#else
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_CONNECT_DEF)
+#endif
+
+  /// Close the connection.
+  /**
+   * @return \c this if a connection was successfully established, a null
+   * pointer otherwise.
+   */
+  basic_socket_streambuf* close()
+  {
+    sync();
+    socket().close(ec_);
+    if (!ec_)
+      init_buffers();
+    return !ec_ ? this : 0;
+  }
+
+  /// Get a reference to the underlying socket.
+  basic_socket<Protocol>& socket()
+  {
+    return *this;
+  }
+
+  /// Get the last error associated with the stream buffer.
+  /**
+   * @return An \c error_code corresponding to the last error from the stream
+   * buffer.
+   */
+  const boost::system::error_code& error() const
+  {
+    return ec_;
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use error().) Get the last error associated with the stream
+  /// buffer.
+  /**
+   * @return An \c error_code corresponding to the last error from the stream
+   * buffer.
+   */
+  const boost::system::error_code& puberror() const
+  {
+    return error();
+  }
+
+  /// (Deprecated: Use expiry().) Get the stream buffer's expiry time as an
+  /// absolute time.
+  /**
+   * @return An absolute time value representing the stream buffer's expiry
+   * time.
+   */
+  time_point expires_at() const
+  {
+    return expiry_time_;
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  /// Get the stream buffer's expiry time as an absolute time.
+  /**
+   * @return An absolute time value representing the stream buffer's expiry
+   * time.
+   */
+  time_point expiry() const
+  {
+    return expiry_time_;
+  }
+
+  /// Set the stream buffer's expiry time as an absolute time.
+  /**
+   * This function sets the expiry time associated with the stream. Stream
+   * operations performed after this time (where the operations cannot be
+   * completed using the internal buffers) will fail with the error
+   * boost::asio::error::operation_aborted.
+   *
+   * @param expiry_time The expiry time to be used for the stream.
+   */
+  void expires_at(const time_point& expiry_time)
+  {
+    expiry_time_ = expiry_time;
+  }
+
+  /// Set the stream buffer's expiry time relative to now.
+  /**
+   * This function sets the expiry time associated with the stream. Stream
+   * operations performed after this time (where the operations cannot be
+   * completed using the internal buffers) will fail with the error
+   * boost::asio::error::operation_aborted.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   */
+  void expires_after(const duration& expiry_time)
+  {
+    expiry_time_ = traits_helper::add(traits_helper::now(), expiry_time);
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use expiry().) Get the stream buffer's expiry time relative
+  /// to now.
+  /**
+   * @return A relative time value representing the stream buffer's expiry time.
+   */
+  duration expires_from_now() const
+  {
+    return traits_helper::subtract(expires_at(), traits_helper::now());
+  }
+
+  /// (Deprecated: Use expires_after().) Set the stream buffer's expiry time
+  /// relative to now.
+  /**
+   * This function sets the expiry time associated with the stream. Stream
+   * operations performed after this time (where the operations cannot be
+   * completed using the internal buffers) will fail with the error
+   * boost::asio::error::operation_aborted.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   */
+  void expires_from_now(const duration& expiry_time)
+  {
+    expiry_time_ = traits_helper::add(traits_helper::now(), expiry_time);
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+protected:
+  int_type underflow()
+  {
+#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    ec_ = boost::asio::error::operation_not_supported;
+    return traits_type::eof();
+#else // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    if (gptr() != egptr())
+      return traits_type::eof();
+
+    for (;;)
+    {
+      // Check if we are past the expiry time.
+      if (traits_helper::less_than(expiry_time_, traits_helper::now()))
+      {
+        ec_ = boost::asio::error::timed_out;
+        return traits_type::eof();
+      }
+
+      // Try to complete the operation without blocking.
+      if (!socket().native_non_blocking())
+        socket().native_non_blocking(true, ec_);
+      detail::buffer_sequence_adapter<mutable_buffer, mutable_buffer>
+        bufs(boost::asio::buffer(get_buffer_) + putback_max);
+      detail::signed_size_type bytes = detail::socket_ops::recv(
+          socket().native_handle(), bufs.buffers(), bufs.count(), 0, ec_);
+
+      // Check if operation succeeded.
+      if (bytes > 0)
+      {
+        setg(&get_buffer_[0], &get_buffer_[0] + putback_max,
+            &get_buffer_[0] + putback_max + bytes);
+        return traits_type::to_int_type(*gptr());
+      }
+
+      // Check for EOF.
+      if (bytes == 0)
+      {
+        ec_ = boost::asio::error::eof;
+        return traits_type::eof();
+      }
+
+      // Operation failed.
+      if (ec_ != boost::asio::error::would_block
+          && ec_ != boost::asio::error::try_again)
+        return traits_type::eof();
+
+      // Wait for socket to become ready.
+      if (detail::socket_ops::poll_read(
+            socket().native_handle(), 0, timeout(), ec_) < 0)
+        return traits_type::eof();
+    }
+#endif // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+  }
+
+  int_type overflow(int_type c)
+  {
+#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    ec_ = boost::asio::error::operation_not_supported;
+    return traits_type::eof();
+#else // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    char_type ch = traits_type::to_char_type(c);
+
+    // Determine what needs to be sent.
+    const_buffer output_buffer;
+    if (put_buffer_.empty())
+    {
+      if (traits_type::eq_int_type(c, traits_type::eof()))
+        return traits_type::not_eof(c); // Nothing to do.
+      output_buffer = boost::asio::buffer(&ch, sizeof(char_type));
+    }
+    else
+    {
+      output_buffer = boost::asio::buffer(pbase(),
+          (pptr() - pbase()) * sizeof(char_type));
+    }
+
+    while (output_buffer.size() > 0)
+    {
+      // Check if we are past the expiry time.
+      if (traits_helper::less_than(expiry_time_, traits_helper::now()))
+      {
+        ec_ = boost::asio::error::timed_out;
+        return traits_type::eof();
+      }
+
+      // Try to complete the operation without blocking.
+      if (!socket().native_non_blocking())
+        socket().native_non_blocking(true, ec_);
+      detail::buffer_sequence_adapter<
+        const_buffer, const_buffer> bufs(output_buffer);
+      detail::signed_size_type bytes = detail::socket_ops::send(
+          socket().native_handle(), bufs.buffers(), bufs.count(), 0, ec_);
+
+      // Check if operation succeeded.
+      if (bytes > 0)
+      {
+        output_buffer += static_cast<std::size_t>(bytes);
+        continue;
+      }
+
+      // Operation failed.
+      if (ec_ != boost::asio::error::would_block
+          && ec_ != boost::asio::error::try_again)
+        return traits_type::eof();
+
+      // Wait for socket to become ready.
+      if (detail::socket_ops::poll_write(
+            socket().native_handle(), 0, timeout(), ec_) < 0)
+        return traits_type::eof();
+    }
+
+    if (!put_buffer_.empty())
+    {
+      setp(&put_buffer_[0], &put_buffer_[0] + put_buffer_.size());
+
+      // If the new character is eof then our work here is done.
+      if (traits_type::eq_int_type(c, traits_type::eof()))
+        return traits_type::not_eof(c);
+
+      // Add the new character to the output buffer.
+      *pptr() = ch;
+      pbump(1);
+    }
+
+    return c;
+#endif // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+  }
+
+  int sync()
+  {
+    return overflow(traits_type::eof());
+  }
+
+  std::streambuf* setbuf(char_type* s, std::streamsize n)
+  {
+    if (pptr() == pbase() && s == 0 && n == 0)
+    {
+      put_buffer_.clear();
+      setp(0, 0);
+      sync();
+      return this;
+    }
+
+    return 0;
+  }
+
+private:
+  // Disallow copying and assignment.
+  basic_socket_streambuf(const basic_socket_streambuf&) BOOST_ASIO_DELETED;
+  basic_socket_streambuf& operator=(
+      const basic_socket_streambuf&) BOOST_ASIO_DELETED;
+
+  void init_buffers()
+  {
+    setg(&get_buffer_[0],
+        &get_buffer_[0] + putback_max,
+        &get_buffer_[0] + putback_max);
+
+    if (put_buffer_.empty())
+      setp(0, 0);
+    else
+      setp(&put_buffer_[0], &put_buffer_[0] + put_buffer_.size());
+  }
+
+  int timeout() const
+  {
+    int64_t msec = traits_helper::to_posix_duration(
+        traits_helper::subtract(expiry_time_,
+          traits_helper::now())).total_milliseconds();
+    if (msec > (std::numeric_limits<int>::max)())
+      msec = (std::numeric_limits<int>::max)();
+    else if (msec < 0)
+      msec = 0;
+    return static_cast<int>(msec);
+  }
+
+  template <typename EndpointSequence>
+  void connect_to_endpoints(const EndpointSequence& endpoints)
+  {
+    this->connect_to_endpoints(endpoints.begin(), endpoints.end());
+  }
+
+  template <typename EndpointIterator>
+  void connect_to_endpoints(EndpointIterator begin, EndpointIterator end)
+  {
+#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    ec_ = boost::asio::error::operation_not_supported;
+#else // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    if (ec_)
+      return;
+
+    ec_ = boost::asio::error::not_found;
+    for (EndpointIterator i = begin; i != end; ++i)
+    {
+      // Check if we are past the expiry time.
+      if (traits_helper::less_than(expiry_time_, traits_helper::now()))
+      {
+        ec_ = boost::asio::error::timed_out;
+        return;
+      }
+
+      // Close and reopen the socket.
+      typename Protocol::endpoint ep(*i);
+      socket().close(ec_);
+      socket().open(ep.protocol(), ec_);
+      if (ec_)
+        continue;
+
+      // Try to complete the operation without blocking.
+      if (!socket().native_non_blocking())
+        socket().native_non_blocking(true, ec_);
+      detail::socket_ops::connect(socket().native_handle(),
+          ep.data(), ep.size(), ec_);
+
+      // Check if operation succeeded.
+      if (!ec_)
+        return;
+
+      // Operation failed.
+      if (ec_ != boost::asio::error::in_progress
+          && ec_ != boost::asio::error::would_block)
+        continue;
+
+      // Wait for socket to become ready.
+      if (detail::socket_ops::poll_connect(
+            socket().native_handle(), timeout(), ec_) < 0)
+        continue;
+
+      // Get the error code from the connect operation.
+      int connect_error = 0;
+      size_t connect_error_len = sizeof(connect_error);
+      if (detail::socket_ops::getsockopt(socket().native_handle(), 0,
+            SOL_SOCKET, SO_ERROR, &connect_error, &connect_error_len, ec_)
+          == detail::socket_error_retval)
+        return;
+
+      // Check the result of the connect operation.
+      ec_ = boost::system::error_code(connect_error,
+          boost::asio::error::get_system_category());
+      if (!ec_)
+        return;
+    }
+#endif // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+  }
+
+  // Helper function to get the maximum expiry time.
+  static time_point max_expiry_time()
+  {
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+    return boost::posix_time::pos_infin;
+#else // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+      // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+    return (time_point::max)();
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // && defined(BOOST_ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
+  }
+
+  enum { putback_max = 8 };
+  boost::system::error_code ec_;
+  time_point expiry_time_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#if !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+# undef BOOST_ASIO_PRIVATE_CONNECT_DEF
+#endif // !defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#endif // BOOST_ASIO_BASIC_SOCKET_STREAMBUF_HPP

boost/asio/basic_stream_socket.hpp

@@ -0,0 +1,995 @@
+//
+// basic_stream_socket.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_STREAM_SOCKET_HPP
+#define BOOST_ASIO_BASIC_STREAM_SOCKET_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/basic_socket.hpp>
+#include <boost/asio/detail/handler_type_requirements.hpp>
+#include <boost/asio/detail/non_const_lvalue.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+#include <boost/asio/error.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+#if !defined(BOOST_ASIO_BASIC_STREAM_SOCKET_FWD_DECL)
+#define BOOST_ASIO_BASIC_STREAM_SOCKET_FWD_DECL
+
+// Forward declaration with defaulted arguments.
+template <typename Protocol, typename Executor = executor>
+class basic_stream_socket;
+
+#endif // !defined(BOOST_ASIO_BASIC_STREAM_SOCKET_FWD_DECL)
+
+/// Provides stream-oriented socket functionality.
+/**
+ * The basic_stream_socket class template provides asynchronous and blocking
+ * stream-oriented socket functionality.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ *
+ * @par Concepts:
+ * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
+ */
+template <typename Protocol, typename Executor>
+class basic_stream_socket
+  : public basic_socket<Protocol, Executor>
+{
+public:
+  /// The type of the executor associated with the object.
+  typedef Executor executor_type;
+
+  /// Rebinds the socket type to another executor.
+  template <typename Executor1>
+  struct rebind_executor
+  {
+    /// The socket type when rebound to the specified executor.
+    typedef basic_stream_socket<Protocol, Executor1> other;
+  };
+
+  /// The native representation of a socket.
+#if defined(GENERATING_DOCUMENTATION)
+  typedef implementation_defined native_handle_type;
+#else
+  typedef typename basic_socket<Protocol,
+    Executor>::native_handle_type native_handle_type;
+#endif
+
+  /// The protocol type.
+  typedef Protocol protocol_type;
+
+  /// The endpoint type.
+  typedef typename Protocol::endpoint endpoint_type;
+
+  /// Construct a basic_stream_socket without opening it.
+  /**
+   * This constructor creates a stream socket without opening it. The socket
+   * needs to be opened and then connected or accepted before data can be sent
+   * or received on it.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   */
+  explicit basic_stream_socket(const executor_type& ex)
+    : basic_socket<Protocol, Executor>(ex)
+  {
+  }
+
+  /// Construct a basic_stream_socket without opening it.
+  /**
+   * This constructor creates a stream socket without opening it. The socket
+   * needs to be opened and then connected or accepted before data can be sent
+   * or received on it.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   */
+  template <typename ExecutionContext>
+  explicit basic_stream_socket(ExecutionContext& context,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context)
+  {
+  }
+
+  /// Construct and open a basic_stream_socket.
+  /**
+   * This constructor creates and opens a stream socket. The socket needs to be
+   * connected or accepted before data can be sent or received on it.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  basic_stream_socket(const executor_type& ex, const protocol_type& protocol)
+    : basic_socket<Protocol, Executor>(ex, protocol)
+  {
+  }
+
+  /// Construct and open a basic_stream_socket.
+  /**
+   * This constructor creates and opens a stream socket. The socket needs to be
+   * connected or accepted before data can be sent or received on it.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  template <typename ExecutionContext>
+  basic_stream_socket(ExecutionContext& context, const protocol_type& protocol,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context, protocol)
+  {
+  }
+
+  /// Construct a basic_stream_socket, opening it and binding it to the given
+  /// local endpoint.
+  /**
+   * This constructor creates a stream socket and automatically opens it bound
+   * to the specified endpoint on the local machine. The protocol used is the
+   * protocol associated with the given endpoint.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   *
+   * @param endpoint An endpoint on the local machine to which the stream
+   * socket will be bound.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  basic_stream_socket(const executor_type& ex, const endpoint_type& endpoint)
+    : basic_socket<Protocol, Executor>(ex, endpoint)
+  {
+  }
+
+  /// Construct a basic_stream_socket, opening it and binding it to the given
+  /// local endpoint.
+  /**
+   * This constructor creates a stream socket and automatically opens it bound
+   * to the specified endpoint on the local machine. The protocol used is the
+   * protocol associated with the given endpoint.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   *
+   * @param endpoint An endpoint on the local machine to which the stream
+   * socket will be bound.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  template <typename ExecutionContext>
+  basic_stream_socket(ExecutionContext& context, const endpoint_type& endpoint,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context, endpoint)
+  {
+  }
+
+  /// Construct a basic_stream_socket on an existing native socket.
+  /**
+   * This constructor creates a stream socket object to hold an existing native
+   * socket.
+   *
+   * @param ex The I/O executor that the socket will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @param native_socket The new underlying socket implementation.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  basic_stream_socket(const executor_type& ex,
+      const protocol_type& protocol, const native_handle_type& native_socket)
+    : basic_socket<Protocol, Executor>(ex, protocol, native_socket)
+  {
+  }
+
+  /// Construct a basic_stream_socket on an existing native socket.
+  /**
+   * This constructor creates a stream socket object to hold an existing native
+   * socket.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the socket will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the socket.
+   *
+   * @param protocol An object specifying protocol parameters to be used.
+   *
+   * @param native_socket The new underlying socket implementation.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  template <typename ExecutionContext>
+  basic_stream_socket(ExecutionContext& context,
+      const protocol_type& protocol, const native_handle_type& native_socket,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(context, protocol, native_socket)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Move-construct a basic_stream_socket from another.
+  /**
+   * This constructor moves a stream socket from one object to another.
+   *
+   * @param other The other basic_stream_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_stream_socket(const executor_type&)
+   * constructor.
+   */
+  basic_stream_socket(basic_stream_socket&& other)
+    : basic_socket<Protocol, Executor>(std::move(other))
+  {
+  }
+
+  /// Move-assign a basic_stream_socket from another.
+  /**
+   * This assignment operator moves a stream socket from one object to another.
+   *
+   * @param other The other basic_stream_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_stream_socket(const executor_type&)
+   * constructor.
+   */
+  basic_stream_socket& operator=(basic_stream_socket&& other)
+  {
+    basic_socket<Protocol, Executor>::operator=(std::move(other));
+    return *this;
+  }
+
+  /// Move-construct a basic_stream_socket from a socket of another protocol
+  /// type.
+  /**
+   * This constructor moves a stream socket from one object to another.
+   *
+   * @param other The other basic_stream_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_stream_socket(const executor_type&)
+   * constructor.
+   */
+  template <typename Protocol1, typename Executor1>
+  basic_stream_socket(basic_stream_socket<Protocol1, Executor1>&& other,
+      typename enable_if<
+        is_convertible<Protocol1, Protocol>::value
+          && is_convertible<Executor1, Executor>::value
+      >::type* = 0)
+    : basic_socket<Protocol, Executor>(std::move(other))
+  {
+  }
+
+  /// Move-assign a basic_stream_socket from a socket of another protocol type.
+  /**
+   * This assignment operator moves a stream socket from one object to another.
+   *
+   * @param other The other basic_stream_socket object from which the move
+   * will occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_stream_socket(const executor_type&)
+   * constructor.
+   */
+  template <typename Protocol1, typename Executor1>
+  typename enable_if<
+    is_convertible<Protocol1, Protocol>::value
+      && is_convertible<Executor1, Executor>::value,
+    basic_stream_socket&
+  >::type operator=(basic_stream_socket<Protocol1, Executor1>&& other)
+  {
+    basic_socket<Protocol, Executor>::operator=(std::move(other));
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Destroys the socket.
+  /**
+   * This function destroys the socket, cancelling any outstanding asynchronous
+   * operations associated with the socket as if by calling @c cancel.
+   */
+  ~basic_stream_socket()
+  {
+  }
+
+  /// Send some data on the socket.
+  /**
+   * This function is used to send data on the stream socket. The function
+   * call will block until one or more bytes of the data has been sent
+   * successfully, or an until error occurs.
+   *
+   * @param buffers One or more data buffers to be sent on the socket.
+   *
+   * @returns The number of bytes sent.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note The send operation may not transmit all of the data to the peer.
+   * Consider using the @ref write function if you need to ensure that all data
+   * is written before the blocking operation completes.
+   *
+   * @par Example
+   * To send a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.send(boost::asio::buffer(data, size));
+   * @endcode
+   * See the @ref buffer documentation for information on sending multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t send(const ConstBufferSequence& buffers)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().send(
+        this->impl_.get_implementation(), buffers, 0, ec);
+    boost::asio::detail::throw_error(ec, "send");
+    return s;
+  }
+
+  /// Send some data on the socket.
+  /**
+   * This function is used to send data on the stream socket. The function
+   * call will block until one or more bytes of the data has been sent
+   * successfully, or an until error occurs.
+   *
+   * @param buffers One or more data buffers to be sent on the socket.
+   *
+   * @param flags Flags specifying how the send call is to be made.
+   *
+   * @returns The number of bytes sent.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note The send operation may not transmit all of the data to the peer.
+   * Consider using the @ref write function if you need to ensure that all data
+   * is written before the blocking operation completes.
+   *
+   * @par Example
+   * To send a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.send(boost::asio::buffer(data, size), 0);
+   * @endcode
+   * See the @ref buffer documentation for information on sending multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t send(const ConstBufferSequence& buffers,
+      socket_base::message_flags flags)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().send(
+        this->impl_.get_implementation(), buffers, flags, ec);
+    boost::asio::detail::throw_error(ec, "send");
+    return s;
+  }
+
+  /// Send some data on the socket.
+  /**
+   * This function is used to send data on the stream socket. The function
+   * call will block until one or more bytes of the data has been sent
+   * successfully, or an until error occurs.
+   *
+   * @param buffers One or more data buffers to be sent on the socket.
+   *
+   * @param flags Flags specifying how the send call is to be made.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes sent. Returns 0 if an error occurred.
+   *
+   * @note The send operation may not transmit all of the data to the peer.
+   * Consider using the @ref write function if you need to ensure that all data
+   * is written before the blocking operation completes.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t send(const ConstBufferSequence& buffers,
+      socket_base::message_flags flags, boost::system::error_code& ec)
+  {
+    return this->impl_.get_service().send(
+        this->impl_.get_implementation(), buffers, flags, ec);
+  }
+
+  /// Start an asynchronous send.
+  /**
+   * This function is used to asynchronously send data on the stream socket.
+   * The function call always returns immediately.
+   *
+   * @param buffers One or more data buffers to be sent on the socket. Although
+   * the buffers object may be copied as necessary, ownership of the underlying
+   * memory blocks is retained by the caller, which must guarantee that they
+   * remain valid until the handler is called.
+   *
+   * @param handler The handler to be called when the send operation completes.
+   * Copies will be made of the handler as required. The function signature of
+   * the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes sent.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The send operation may not transmit all of the data to the peer.
+   * Consider using the @ref async_write function if you need to ensure that all
+   * data is written before the asynchronous operation completes.
+   *
+   * @par Example
+   * To send a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.async_send(boost::asio::buffer(data, size), handler);
+   * @endcode
+   * See the @ref buffer documentation for information on sending multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_send(const ConstBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return async_initiate<WriteHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_send(), handler, this,
+        buffers, socket_base::message_flags(0));
+  }
+
+  /// Start an asynchronous send.
+  /**
+   * This function is used to asynchronously send data on the stream socket.
+   * The function call always returns immediately.
+   *
+   * @param buffers One or more data buffers to be sent on the socket. Although
+   * the buffers object may be copied as necessary, ownership of the underlying
+   * memory blocks is retained by the caller, which must guarantee that they
+   * remain valid until the handler is called.
+   *
+   * @param flags Flags specifying how the send call is to be made.
+   *
+   * @param handler The handler to be called when the send operation completes.
+   * Copies will be made of the handler as required. The function signature of
+   * the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes sent.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The send operation may not transmit all of the data to the peer.
+   * Consider using the @ref async_write function if you need to ensure that all
+   * data is written before the asynchronous operation completes.
+   *
+   * @par Example
+   * To send a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.async_send(boost::asio::buffer(data, size), 0, handler);
+   * @endcode
+   * See the @ref buffer documentation for information on sending multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_send(const ConstBufferSequence& buffers,
+      socket_base::message_flags flags,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return async_initiate<WriteHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_send(), handler, this, buffers, flags);
+  }
+
+  /// Receive some data on the socket.
+  /**
+   * This function is used to receive data on the stream socket. The function
+   * call will block until one or more bytes of data has been received
+   * successfully, or until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   *
+   * @returns The number of bytes received.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @note The receive operation may not receive all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that the
+   * requested amount of data is read before the blocking operation completes.
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.receive(boost::asio::buffer(data, size));
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t receive(const MutableBufferSequence& buffers)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().receive(
+        this->impl_.get_implementation(), buffers, 0, ec);
+    boost::asio::detail::throw_error(ec, "receive");
+    return s;
+  }
+
+  /// Receive some data on the socket.
+  /**
+   * This function is used to receive data on the stream socket. The function
+   * call will block until one or more bytes of data has been received
+   * successfully, or until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   *
+   * @param flags Flags specifying how the receive call is to be made.
+   *
+   * @returns The number of bytes received.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @note The receive operation may not receive all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that the
+   * requested amount of data is read before the blocking operation completes.
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.receive(boost::asio::buffer(data, size), 0);
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags flags)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().receive(
+        this->impl_.get_implementation(), buffers, flags, ec);
+    boost::asio::detail::throw_error(ec, "receive");
+    return s;
+  }
+
+  /// Receive some data on a connected socket.
+  /**
+   * This function is used to receive data on the stream socket. The function
+   * call will block until one or more bytes of data has been received
+   * successfully, or until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   *
+   * @param flags Flags specifying how the receive call is to be made.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes received. Returns 0 if an error occurred.
+   *
+   * @note The receive operation may not receive all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that the
+   * requested amount of data is read before the blocking operation completes.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags flags, boost::system::error_code& ec)
+  {
+    return this->impl_.get_service().receive(
+        this->impl_.get_implementation(), buffers, flags, ec);
+  }
+
+  /// Start an asynchronous receive.
+  /**
+   * This function is used to asynchronously receive data from the stream
+   * socket. The function call always returns immediately.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param handler The handler to be called when the receive operation
+   * completes. Copies will be made of the handler as required. The function
+   * signature of the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes received.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The receive operation may not receive all of the requested number of
+   * bytes. Consider using the @ref async_read function if you need to ensure
+   * that the requested amount of data is received before the asynchronous
+   * operation completes.
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.async_receive(boost::asio::buffer(data, size), handler);
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_receive(const MutableBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return async_initiate<ReadHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_receive(), handler, this,
+        buffers, socket_base::message_flags(0));
+  }
+
+  /// Start an asynchronous receive.
+  /**
+   * This function is used to asynchronously receive data from the stream
+   * socket. The function call always returns immediately.
+   *
+   * @param buffers One or more buffers into which the data will be received.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param flags Flags specifying how the receive call is to be made.
+   *
+   * @param handler The handler to be called when the receive operation
+   * completes. Copies will be made of the handler as required. The function
+   * signature of the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes received.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The receive operation may not receive all of the requested number of
+   * bytes. Consider using the @ref async_read function if you need to ensure
+   * that the requested amount of data is received before the asynchronous
+   * operation completes.
+   *
+   * @par Example
+   * To receive into a single data buffer use the @ref buffer function as
+   * follows:
+   * @code
+   * socket.async_receive(boost::asio::buffer(data, size), 0, handler);
+   * @endcode
+   * See the @ref buffer documentation for information on receiving into
+   * multiple buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_receive(const MutableBufferSequence& buffers,
+      socket_base::message_flags flags,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return async_initiate<ReadHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_receive(), handler, this, buffers, flags);
+  }
+
+  /// Write some data to the socket.
+  /**
+   * This function is used to write data to the stream socket. The function call
+   * will block until one or more bytes of the data has been written
+   * successfully, or until an error occurs.
+   *
+   * @param buffers One or more data buffers to be written to the socket.
+   *
+   * @returns The number of bytes written.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @note The write_some operation may not transmit all of the data to the
+   * peer. Consider using the @ref write function if you need to ensure that
+   * all data is written before the blocking operation completes.
+   *
+   * @par Example
+   * To write a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.write_some(boost::asio::buffer(data, size));
+   * @endcode
+   * See the @ref buffer documentation for information on writing multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().send(
+        this->impl_.get_implementation(), buffers, 0, ec);
+    boost::asio::detail::throw_error(ec, "write_some");
+    return s;
+  }
+
+  /// Write some data to the socket.
+  /**
+   * This function is used to write data to the stream socket. The function call
+   * will block until one or more bytes of the data has been written
+   * successfully, or until an error occurs.
+   *
+   * @param buffers One or more data buffers to be written to the socket.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes written. Returns 0 if an error occurred.
+   *
+   * @note The write_some operation may not transmit all of the data to the
+   * peer. Consider using the @ref write function if you need to ensure that
+   * all data is written before the blocking operation completes.
+   */
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return this->impl_.get_service().send(
+        this->impl_.get_implementation(), buffers, 0, ec);
+  }
+
+  /// Start an asynchronous write.
+  /**
+   * This function is used to asynchronously write data to the stream socket.
+   * The function call always returns immediately.
+   *
+   * @param buffers One or more data buffers to be written to the socket.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param handler The handler to be called when the write operation completes.
+   * Copies will be made of the handler as required. The function signature of
+   * the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes written.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The write operation may not transmit all of the data to the peer.
+   * Consider using the @ref async_write function if you need to ensure that all
+   * data is written before the asynchronous operation completes.
+   *
+   * @par Example
+   * To write a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.async_write_some(boost::asio::buffer(data, size), handler);
+   * @endcode
+   * See the @ref buffer documentation for information on writing multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_write_some(const ConstBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return async_initiate<WriteHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_send(), handler, this,
+        buffers, socket_base::message_flags(0));
+  }
+
+  /// Read some data from the socket.
+  /**
+   * This function is used to read data from the stream socket. The function
+   * call will block until one or more bytes of data has been read successfully,
+   * or until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be read.
+   *
+   * @returns The number of bytes read.
+   *
+   * @throws boost::system::system_error Thrown on failure. An error code of
+   * boost::asio::error::eof indicates that the connection was closed by the
+   * peer.
+   *
+   * @note The read_some operation may not read all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that
+   * the requested amount of data is read before the blocking operation
+   * completes.
+   *
+   * @par Example
+   * To read into a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.read_some(boost::asio::buffer(data, size));
+   * @endcode
+   * See the @ref buffer documentation for information on reading into multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers)
+  {
+    boost::system::error_code ec;
+    std::size_t s = this->impl_.get_service().receive(
+        this->impl_.get_implementation(), buffers, 0, ec);
+    boost::asio::detail::throw_error(ec, "read_some");
+    return s;
+  }
+
+  /// Read some data from the socket.
+  /**
+   * This function is used to read data from the stream socket. The function
+   * call will block until one or more bytes of data has been read successfully,
+   * or until an error occurs.
+   *
+   * @param buffers One or more buffers into which the data will be read.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @returns The number of bytes read. Returns 0 if an error occurred.
+   *
+   * @note The read_some operation may not read all of the requested number of
+   * bytes. Consider using the @ref read function if you need to ensure that
+   * the requested amount of data is read before the blocking operation
+   * completes.
+   */
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return this->impl_.get_service().receive(
+        this->impl_.get_implementation(), buffers, 0, ec);
+  }
+
+  /// Start an asynchronous read.
+  /**
+   * This function is used to asynchronously read data from the stream socket.
+   * The function call always returns immediately.
+   *
+   * @param buffers One or more buffers into which the data will be read.
+   * Although the buffers object may be copied as necessary, ownership of the
+   * underlying memory blocks is retained by the caller, which must guarantee
+   * that they remain valid until the handler is called.
+   *
+   * @param handler The handler to be called when the read operation completes.
+   * Copies will be made of the handler as required. The function signature of
+   * the handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error, // Result of operation.
+   *   std::size_t bytes_transferred           // Number of bytes read.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   *
+   * @note The read operation may not read all of the requested number of bytes.
+   * Consider using the @ref async_read function if you need to ensure that the
+   * requested amount of data is read before the asynchronous operation
+   * completes.
+   *
+   * @par Example
+   * To read into a single data buffer use the @ref buffer function as follows:
+   * @code
+   * socket.async_read_some(boost::asio::buffer(data, size), handler);
+   * @endcode
+   * See the @ref buffer documentation for information on reading into multiple
+   * buffers in one go, and how to use it with arrays, boost::array or
+   * std::vector.
+   */
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_read_some(const MutableBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return async_initiate<ReadHandler,
+      void (boost::system::error_code, std::size_t)>(
+        initiate_async_receive(), handler, this,
+        buffers, socket_base::message_flags(0));
+  }
+
+private:
+  struct initiate_async_send
+  {
+    template <typename WriteHandler, typename ConstBufferSequence>
+    void operator()(BOOST_ASIO_MOVE_ARG(WriteHandler) handler,
+        basic_stream_socket* self, const ConstBufferSequence& buffers,
+        socket_base::message_flags flags) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a WriteHandler.
+      BOOST_ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
+
+      detail::non_const_lvalue<WriteHandler> handler2(handler);
+      self->impl_.get_service().async_send(
+          self->impl_.get_implementation(), buffers, flags,
+          handler2.value, self->impl_.get_implementation_executor());
+    }
+  };
+
+  struct initiate_async_receive
+  {
+    template <typename ReadHandler, typename MutableBufferSequence>
+    void operator()(BOOST_ASIO_MOVE_ARG(ReadHandler) handler,
+        basic_stream_socket* self, const MutableBufferSequence& buffers,
+        socket_base::message_flags flags) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a ReadHandler.
+      BOOST_ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
+
+      detail::non_const_lvalue<ReadHandler> handler2(handler);
+      self->impl_.get_service().async_receive(
+          self->impl_.get_implementation(), buffers, flags,
+          handler2.value, self->impl_.get_implementation_executor());
+    }
+  };
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_BASIC_STREAM_SOCKET_HPP

boost/asio/basic_streambuf.hpp

@@ -0,0 +1,454 @@
+//
+// basic_streambuf.hpp
+// ~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_STREAMBUF_HPP
+#define BOOST_ASIO_BASIC_STREAMBUF_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#include <algorithm>
+#include <cstring>
+#include <stdexcept>
+#include <streambuf>
+#include <vector>
+#include <boost/asio/basic_streambuf_fwd.hpp>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/detail/limits.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/detail/throw_exception.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Automatically resizable buffer class based on std::streambuf.
+/**
+ * The @c basic_streambuf class is derived from @c std::streambuf to associate
+ * the streambuf's input and output sequences with one or more character
+ * arrays. These character arrays are internal to the @c basic_streambuf
+ * object, but direct access to the array elements is provided to permit them
+ * to be used efficiently with I/O operations. Characters written to the output
+ * sequence of a @c basic_streambuf object are appended to the input sequence
+ * of the same object.
+ *
+ * The @c basic_streambuf class's public interface is intended to permit the
+ * following implementation strategies:
+ *
+ * @li A single contiguous character array, which is reallocated as necessary
+ * to accommodate changes in the size of the character sequence. This is the
+ * implementation approach currently used in Asio.
+ *
+ * @li A sequence of one or more character arrays, where each array is of the
+ * same size. Additional character array objects are appended to the sequence
+ * to accommodate changes in the size of the character sequence.
+ *
+ * @li A sequence of one or more character arrays of varying sizes. Additional
+ * character array objects are appended to the sequence to accommodate changes
+ * in the size of the character sequence.
+ *
+ * The constructor for basic_streambuf accepts a @c size_t argument specifying
+ * the maximum of the sum of the sizes of the input sequence and output
+ * sequence. During the lifetime of the @c basic_streambuf object, the following
+ * invariant holds:
+ * @code size() <= max_size()@endcode
+ * Any member function that would, if successful, cause the invariant to be
+ * violated shall throw an exception of class @c std::length_error.
+ *
+ * The constructor for @c basic_streambuf takes an Allocator argument. A copy
+ * of this argument is used for any memory allocation performed, by the
+ * constructor and by all member functions, during the lifetime of each @c
+ * basic_streambuf object.
+ *
+ * @par Examples
+ * Writing directly from an streambuf to a socket:
+ * @code
+ * boost::asio::streambuf b;
+ * std::ostream os(&b);
+ * os << "Hello, World!\n";
+ *
+ * // try sending some data in input sequence
+ * size_t n = sock.send(b.data());
+ *
+ * b.consume(n); // sent data is removed from input sequence
+ * @endcode
+ *
+ * Reading from a socket directly into a streambuf:
+ * @code
+ * boost::asio::streambuf b;
+ *
+ * // reserve 512 bytes in output sequence
+ * boost::asio::streambuf::mutable_buffers_type bufs = b.prepare(512);
+ *
+ * size_t n = sock.receive(bufs);
+ *
+ * // received data is "committed" from output sequence to input sequence
+ * b.commit(n);
+ *
+ * std::istream is(&b);
+ * std::string s;
+ * is >> s;
+ * @endcode
+ */
+#if defined(GENERATING_DOCUMENTATION)
+template <typename Allocator = std::allocator<char> >
+#else
+template <typename Allocator>
+#endif
+class basic_streambuf
+  : public std::streambuf,
+    private noncopyable
+{
+public:
+#if defined(GENERATING_DOCUMENTATION)
+  /// The type used to represent the input sequence as a list of buffers.
+  typedef implementation_defined const_buffers_type;
+
+  /// The type used to represent the output sequence as a list of buffers.
+  typedef implementation_defined mutable_buffers_type;
+#else
+  typedef BOOST_ASIO_CONST_BUFFER const_buffers_type;
+  typedef BOOST_ASIO_MUTABLE_BUFFER mutable_buffers_type;
+#endif
+
+  /// Construct a basic_streambuf object.
+  /**
+   * Constructs a streambuf with the specified maximum size. The initial size
+   * of the streambuf's input sequence is 0.
+   */
+  explicit basic_streambuf(
+      std::size_t maximum_size = (std::numeric_limits<std::size_t>::max)(),
+      const Allocator& allocator = Allocator())
+    : max_size_(maximum_size),
+      buffer_(allocator)
+  {
+    std::size_t pend = (std::min<std::size_t>)(max_size_, buffer_delta);
+    buffer_.resize((std::max<std::size_t>)(pend, 1));
+    setg(&buffer_[0], &buffer_[0], &buffer_[0]);
+    setp(&buffer_[0], &buffer_[0] + pend);
+  }
+
+  /// Get the size of the input sequence.
+  /**
+   * @returns The size of the input sequence. The value is equal to that
+   * calculated for @c s in the following code:
+   * @code
+   * size_t s = 0;
+   * const_buffers_type bufs = data();
+   * const_buffers_type::const_iterator i = bufs.begin();
+   * while (i != bufs.end())
+   * {
+   *   const_buffer buf(*i++);
+   *   s += buf.size();
+   * }
+   * @endcode
+   */
+  std::size_t size() const BOOST_ASIO_NOEXCEPT
+  {
+    return pptr() - gptr();
+  }
+
+  /// Get the maximum size of the basic_streambuf.
+  /**
+   * @returns The allowed maximum of the sum of the sizes of the input sequence
+   * and output sequence.
+   */
+  std::size_t max_size() const BOOST_ASIO_NOEXCEPT
+  {
+    return max_size_;
+  }
+
+  /// Get the current capacity of the basic_streambuf.
+  /**
+   * @returns The current total capacity of the streambuf, i.e. for both the
+   * input sequence and output sequence.
+   */
+  std::size_t capacity() const BOOST_ASIO_NOEXCEPT
+  {
+    return buffer_.capacity();
+  }
+
+  /// Get a list of buffers that represents the input sequence.
+  /**
+   * @returns An object of type @c const_buffers_type that satisfies
+   * ConstBufferSequence requirements, representing all character arrays in the
+   * input sequence.
+   *
+   * @note The returned object is invalidated by any @c basic_streambuf member
+   * function that modifies the input sequence or output sequence.
+   */
+  const_buffers_type data() const BOOST_ASIO_NOEXCEPT
+  {
+    return boost::asio::buffer(boost::asio::const_buffer(gptr(),
+          (pptr() - gptr()) * sizeof(char_type)));
+  }
+
+  /// Get a list of buffers that represents the output sequence, with the given
+  /// size.
+  /**
+   * Ensures that the output sequence can accommodate @c n characters,
+   * reallocating character array objects as necessary.
+   *
+   * @returns An object of type @c mutable_buffers_type that satisfies
+   * MutableBufferSequence requirements, representing character array objects
+   * at the start of the output sequence such that the sum of the buffer sizes
+   * is @c n.
+   *
+   * @throws std::length_error If <tt>size() + n > max_size()</tt>.
+   *
+   * @note The returned object is invalidated by any @c basic_streambuf member
+   * function that modifies the input sequence or output sequence.
+   */
+  mutable_buffers_type prepare(std::size_t n)
+  {
+    reserve(n);
+    return boost::asio::buffer(boost::asio::mutable_buffer(
+          pptr(), n * sizeof(char_type)));
+  }
+
+  /// Move characters from the output sequence to the input sequence.
+  /**
+   * Appends @c n characters from the start of the output sequence to the input
+   * sequence. The beginning of the output sequence is advanced by @c n
+   * characters.
+   *
+   * Requires a preceding call <tt>prepare(x)</tt> where <tt>x >= n</tt>, and
+   * no intervening operations that modify the input or output sequence.
+   *
+   * @note If @c n is greater than the size of the output sequence, the entire
+   * output sequence is moved to the input sequence and no error is issued.
+   */
+  void commit(std::size_t n)
+  {
+    n = std::min<std::size_t>(n, epptr() - pptr());
+    pbump(static_cast<int>(n));
+    setg(eback(), gptr(), pptr());
+  }
+
+  /// Remove characters from the input sequence.
+  /**
+   * Removes @c n characters from the beginning of the input sequence.
+   *
+   * @note If @c n is greater than the size of the input sequence, the entire
+   * input sequence is consumed and no error is issued.
+   */
+  void consume(std::size_t n)
+  {
+    if (egptr() < pptr())
+      setg(&buffer_[0], gptr(), pptr());
+    if (gptr() + n > pptr())
+      n = pptr() - gptr();
+    gbump(static_cast<int>(n));
+  }
+
+protected:
+  enum { buffer_delta = 128 };
+
+  /// Override std::streambuf behaviour.
+  /**
+   * Behaves according to the specification of @c std::streambuf::underflow().
+   */
+  int_type underflow()
+  {
+    if (gptr() < pptr())
+    {
+      setg(&buffer_[0], gptr(), pptr());
+      return traits_type::to_int_type(*gptr());
+    }
+    else
+    {
+      return traits_type::eof();
+    }
+  }
+
+  /// Override std::streambuf behaviour.
+  /**
+   * Behaves according to the specification of @c std::streambuf::overflow(),
+   * with the specialisation that @c std::length_error is thrown if appending
+   * the character to the input sequence would require the condition
+   * <tt>size() > max_size()</tt> to be true.
+   */
+  int_type overflow(int_type c)
+  {
+    if (!traits_type::eq_int_type(c, traits_type::eof()))
+    {
+      if (pptr() == epptr())
+      {
+        std::size_t buffer_size = pptr() - gptr();
+        if (buffer_size < max_size_ && max_size_ - buffer_size < buffer_delta)
+        {
+          reserve(max_size_ - buffer_size);
+        }
+        else
+        {
+          reserve(buffer_delta);
+        }
+      }
+
+      *pptr() = traits_type::to_char_type(c);
+      pbump(1);
+      return c;
+    }
+
+    return traits_type::not_eof(c);
+  }
+
+  void reserve(std::size_t n)
+  {
+    // Get current stream positions as offsets.
+    std::size_t gnext = gptr() - &buffer_[0];
+    std::size_t pnext = pptr() - &buffer_[0];
+    std::size_t pend = epptr() - &buffer_[0];
+
+    // Check if there is already enough space in the put area.
+    if (n <= pend - pnext)
+    {
+      return;
+    }
+
+    // Shift existing contents of get area to start of buffer.
+    if (gnext > 0)
+    {
+      pnext -= gnext;
+      std::memmove(&buffer_[0], &buffer_[0] + gnext, pnext);
+    }
+
+    // Ensure buffer is large enough to hold at least the specified size.
+    if (n > pend - pnext)
+    {
+      if (n <= max_size_ && pnext <= max_size_ - n)
+      {
+        pend = pnext + n;
+        buffer_.resize((std::max<std::size_t>)(pend, 1));
+      }
+      else
+      {
+        std::length_error ex("boost::asio::streambuf too long");
+        boost::asio::detail::throw_exception(ex);
+      }
+    }
+
+    // Update stream positions.
+    setg(&buffer_[0], &buffer_[0], &buffer_[0] + pnext);
+    setp(&buffer_[0] + pnext, &buffer_[0] + pend);
+  }
+
+private:
+  std::size_t max_size_;
+  std::vector<char_type, Allocator> buffer_;
+
+  // Helper function to get the preferred size for reading data.
+  friend std::size_t read_size_helper(
+      basic_streambuf& sb, std::size_t max_size)
+  {
+    return std::min<std::size_t>(
+        std::max<std::size_t>(512, sb.buffer_.capacity() - sb.size()),
+        std::min<std::size_t>(max_size, sb.max_size() - sb.size()));
+  }
+};
+
+/// Adapts basic_streambuf to the dynamic buffer sequence type requirements.
+#if defined(GENERATING_DOCUMENTATION)
+template <typename Allocator = std::allocator<char> >
+#else
+template <typename Allocator>
+#endif
+class basic_streambuf_ref
+{
+public:
+  /// The type used to represent the input sequence as a list of buffers.
+  typedef typename basic_streambuf<Allocator>::const_buffers_type
+    const_buffers_type;
+
+  /// The type used to represent the output sequence as a list of buffers.
+  typedef typename basic_streambuf<Allocator>::mutable_buffers_type
+    mutable_buffers_type;
+
+  /// Construct a basic_streambuf_ref for the given basic_streambuf object.
+  explicit basic_streambuf_ref(basic_streambuf<Allocator>& sb)
+    : sb_(sb)
+  {
+  }
+
+  /// Copy construct a basic_streambuf_ref.
+  basic_streambuf_ref(const basic_streambuf_ref& other) BOOST_ASIO_NOEXCEPT
+    : sb_(other.sb_)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Move construct a basic_streambuf_ref.
+  basic_streambuf_ref(basic_streambuf_ref&& other) BOOST_ASIO_NOEXCEPT
+    : sb_(other.sb_)
+  {
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Get the size of the input sequence.
+  std::size_t size() const BOOST_ASIO_NOEXCEPT
+  {
+    return sb_.size();
+  }
+
+  /// Get the maximum size of the dynamic buffer.
+  std::size_t max_size() const BOOST_ASIO_NOEXCEPT
+  {
+    return sb_.max_size();
+  }
+
+  /// Get the current capacity of the dynamic buffer.
+  std::size_t capacity() const BOOST_ASIO_NOEXCEPT
+  {
+    return sb_.capacity();
+  }
+
+  /// Get a list of buffers that represents the input sequence.
+  const_buffers_type data() const BOOST_ASIO_NOEXCEPT
+  {
+    return sb_.data();
+  }
+
+  /// Get a list of buffers that represents the output sequence, with the given
+  /// size.
+  mutable_buffers_type prepare(std::size_t n)
+  {
+    return sb_.prepare(n);
+  }
+
+  /// Move bytes from the output sequence to the input sequence.
+  void commit(std::size_t n)
+  {
+    return sb_.commit(n);
+  }
+
+  /// Remove characters from the input sequence.
+  void consume(std::size_t n)
+  {
+    return sb_.consume(n);
+  }
+
+private:
+  basic_streambuf<Allocator>& sb_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#endif // BOOST_ASIO_BASIC_STREAMBUF_HPP

boost/asio/basic_streambuf_fwd.hpp

@@ -0,0 +1,38 @@
+//
+// basic_streambuf_fwd.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_STREAMBUF_FWD_HPP
+#define BOOST_ASIO_BASIC_STREAMBUF_FWD_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#include <memory>
+
+namespace boost {
+namespace asio {
+
+template <typename Allocator = std::allocator<char> >
+class basic_streambuf;
+
+template <typename Allocator = std::allocator<char> >
+class basic_streambuf_ref;
+
+} // namespace asio
+} // namespace boost
+
+#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
+
+#endif // BOOST_ASIO_BASIC_STREAMBUF_FWD_HPP

boost/asio/basic_waitable_timer.hpp

@@ -0,0 +1,738 @@
+//
+// basic_waitable_timer.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BASIC_WAITABLE_TIMER_HPP
+#define BOOST_ASIO_BASIC_WAITABLE_TIMER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/detail/chrono_time_traits.hpp>
+#include <boost/asio/detail/deadline_timer_service.hpp>
+#include <boost/asio/detail/handler_type_requirements.hpp>
+#include <boost/asio/detail/io_object_impl.hpp>
+#include <boost/asio/detail/non_const_lvalue.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/executor.hpp>
+#include <boost/asio/wait_traits.hpp>
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+# include <utility>
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+#if !defined(BOOST_ASIO_BASIC_WAITABLE_TIMER_FWD_DECL)
+#define BOOST_ASIO_BASIC_WAITABLE_TIMER_FWD_DECL
+
+// Forward declaration with defaulted arguments.
+template <typename Clock,
+    typename WaitTraits = boost::asio::wait_traits<Clock>,
+    typename Executor = executor>
+class basic_waitable_timer;
+
+#endif // !defined(BOOST_ASIO_BASIC_WAITABLE_TIMER_FWD_DECL)
+
+/// Provides waitable timer functionality.
+/**
+ * The basic_waitable_timer class template provides the ability to perform a
+ * blocking or asynchronous wait for a timer to expire.
+ *
+ * A waitable timer is always in one of two states: "expired" or "not expired".
+ * If the wait() or async_wait() function is called on an expired timer, the
+ * wait operation will complete immediately.
+ *
+ * Most applications will use one of the boost::asio::steady_timer,
+ * boost::asio::system_timer or boost::asio::high_resolution_timer typedefs.
+ *
+ * @note This waitable timer functionality is for use with the C++11 standard
+ * library's @c &lt;chrono&gt; facility, or with the Boost.Chrono library.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ *
+ * @par Examples
+ * Performing a blocking wait (C++11):
+ * @code
+ * // Construct a timer without setting an expiry time.
+ * boost::asio::steady_timer timer(my_context);
+ *
+ * // Set an expiry time relative to now.
+ * timer.expires_after(std::chrono::seconds(5));
+ *
+ * // Wait for the timer to expire.
+ * timer.wait();
+ * @endcode
+ *
+ * @par 
+ * Performing an asynchronous wait (C++11):
+ * @code
+ * void handler(const boost::system::error_code& error)
+ * {
+ *   if (!error)
+ *   {
+ *     // Timer expired.
+ *   }
+ * }
+ *
+ * ...
+ *
+ * // Construct a timer with an absolute expiry time.
+ * boost::asio::steady_timer timer(my_context,
+ *     std::chrono::steady_clock::now() + std::chrono::seconds(60));
+ *
+ * // Start an asynchronous wait.
+ * timer.async_wait(handler);
+ * @endcode
+ *
+ * @par Changing an active waitable timer's expiry time
+ *
+ * Changing the expiry time of a timer while there are pending asynchronous
+ * waits causes those wait operations to be cancelled. To ensure that the action
+ * associated with the timer is performed only once, use something like this:
+ * used:
+ *
+ * @code
+ * void on_some_event()
+ * {
+ *   if (my_timer.expires_after(seconds(5)) > 0)
+ *   {
+ *     // We managed to cancel the timer. Start new asynchronous wait.
+ *     my_timer.async_wait(on_timeout);
+ *   }
+ *   else
+ *   {
+ *     // Too late, timer has already expired!
+ *   }
+ * }
+ *
+ * void on_timeout(const boost::system::error_code& e)
+ * {
+ *   if (e != boost::asio::error::operation_aborted)
+ *   {
+ *     // Timer was not cancelled, take necessary action.
+ *   }
+ * }
+ * @endcode
+ *
+ * @li The boost::asio::basic_waitable_timer::expires_after() function
+ * cancels any pending asynchronous waits, and returns the number of
+ * asynchronous waits that were cancelled. If it returns 0 then you were too
+ * late and the wait handler has already been executed, or will soon be
+ * executed. If it returns 1 then the wait handler was successfully cancelled.
+ *
+ * @li If a wait handler is cancelled, the boost::system::error_code passed to
+ * it contains the value boost::asio::error::operation_aborted.
+ */
+template <typename Clock, typename WaitTraits, typename Executor>
+class basic_waitable_timer
+{
+public:
+  /// The type of the executor associated with the object.
+  typedef Executor executor_type;
+
+  /// The clock type.
+  typedef Clock clock_type;
+
+  /// The duration type of the clock.
+  typedef typename clock_type::duration duration;
+
+  /// The time point type of the clock.
+  typedef typename clock_type::time_point time_point;
+
+  /// The wait traits type.
+  typedef WaitTraits traits_type;
+
+  /// Constructor.
+  /**
+   * This constructor creates a timer without setting an expiry time. The
+   * expires_at() or expires_after() functions must be called to set an expiry
+   * time before the timer can be waited on.
+   *
+   * @param ex The I/O executor that the timer will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the timer.
+   */
+  explicit basic_waitable_timer(const executor_type& ex)
+    : impl_(ex)
+  {
+  }
+
+  /// Constructor.
+  /**
+   * This constructor creates a timer without setting an expiry time. The
+   * expires_at() or expires_after() functions must be called to set an expiry
+   * time before the timer can be waited on.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the timer will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the timer.
+   */
+  template <typename ExecutionContext>
+  explicit basic_waitable_timer(ExecutionContext& context,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+  }
+
+  /// Constructor to set a particular expiry time as an absolute time.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param ex The I/O executor object that the timer will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, expressed
+   * as an absolute time.
+   */
+  basic_waitable_timer(const executor_type& ex, const time_point& expiry_time)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_at");
+  }
+
+  /// Constructor to set a particular expiry time as an absolute time.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the timer will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, expressed
+   * as an absolute time.
+   */
+  template <typename ExecutionContext>
+  explicit basic_waitable_timer(ExecutionContext& context,
+      const time_point& expiry_time,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_at");
+  }
+
+  /// Constructor to set a particular expiry time relative to now.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param ex The I/O executor that the timer will use, by default, to
+   * dispatch handlers for any asynchronous operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, relative to
+   * now.
+   */
+  basic_waitable_timer(const executor_type& ex, const duration& expiry_time)
+    : impl_(ex)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_after(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_after");
+  }
+
+  /// Constructor to set a particular expiry time relative to now.
+  /**
+   * This constructor creates a timer and sets the expiry time.
+   *
+   * @param context An execution context which provides the I/O executor that
+   * the timer will use, by default, to dispatch handlers for any asynchronous
+   * operations performed on the timer.
+   *
+   * @param expiry_time The expiry time to be used for the timer, relative to
+   * now.
+   */
+  template <typename ExecutionContext>
+  explicit basic_waitable_timer(ExecutionContext& context,
+      const duration& expiry_time,
+      typename enable_if<
+        is_convertible<ExecutionContext&, execution_context&>::value
+      >::type* = 0)
+    : impl_(context)
+  {
+    boost::system::error_code ec;
+    impl_.get_service().expires_after(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_after");
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+  /// Move-construct a basic_waitable_timer from another.
+  /**
+   * This constructor moves a timer from one object to another.
+   *
+   * @param other The other basic_waitable_timer object from which the move will
+   * occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_waitable_timer(const executor_type&)
+   * constructor.
+   */
+  basic_waitable_timer(basic_waitable_timer&& other)
+    : impl_(std::move(other.impl_))
+  {
+  }
+
+  /// Move-assign a basic_waitable_timer from another.
+  /**
+   * This assignment operator moves a timer from one object to another. Cancels
+   * any outstanding asynchronous operations associated with the target object.
+   *
+   * @param other The other basic_waitable_timer object from which the move will
+   * occur.
+   *
+   * @note Following the move, the moved-from object is in the same state as if
+   * constructed using the @c basic_waitable_timer(const executor_type&)
+   * constructor.
+   */
+  basic_waitable_timer& operator=(basic_waitable_timer&& other)
+  {
+    impl_ = std::move(other.impl_);
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Destroys the timer.
+  /**
+   * This function destroys the timer, cancelling any outstanding asynchronous
+   * wait operations associated with the timer as if by calling @c cancel.
+   */
+  ~basic_waitable_timer()
+  {
+  }
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return impl_.get_executor();
+  }
+
+  /// Cancel any asynchronous operations that are waiting on the timer.
+  /**
+   * This function forces the completion of any pending asynchronous wait
+   * operations against the timer. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when cancel() is called, then the
+   * handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel()
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().cancel(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "cancel");
+    return s;
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use non-error_code overload.) Cancel any asynchronous
+  /// operations that are waiting on the timer.
+  /**
+   * This function forces the completion of any pending asynchronous wait
+   * operations against the timer. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @note If the timer has already expired when cancel() is called, then the
+   * handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel(boost::system::error_code& ec)
+  {
+    return impl_.get_service().cancel(impl_.get_implementation(), ec);
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  /// Cancels one asynchronous operation that is waiting on the timer.
+  /**
+   * This function forces the completion of one pending asynchronous wait
+   * operation against the timer. Handlers are cancelled in FIFO order. The
+   * handler for the cancelled operation will be invoked with the
+   * boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @return The number of asynchronous operations that were cancelled. That is,
+   * either 0 or 1.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when cancel_one() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel_one()
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().cancel_one(
+        impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "cancel_one");
+    return s;
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use non-error_code overload.) Cancels one asynchronous
+  /// operation that is waiting on the timer.
+  /**
+   * This function forces the completion of one pending asynchronous wait
+   * operation against the timer. Handlers are cancelled in FIFO order. The
+   * handler for the cancelled operation will be invoked with the
+   * boost::asio::error::operation_aborted error code.
+   *
+   * Cancelling the timer does not change the expiry time.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled. That is,
+   * either 0 or 1.
+   *
+   * @note If the timer has already expired when cancel_one() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t cancel_one(boost::system::error_code& ec)
+  {
+    return impl_.get_service().cancel_one(impl_.get_implementation(), ec);
+  }
+
+  /// (Deprecated: Use expiry().) Get the timer's expiry time as an absolute
+  /// time.
+  /**
+   * This function may be used to obtain the timer's current expiry time.
+   * Whether the timer has expired or not does not affect this value.
+   */
+  time_point expires_at() const
+  {
+    return impl_.get_service().expires_at(impl_.get_implementation());
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  /// Get the timer's expiry time as an absolute time.
+  /**
+   * This function may be used to obtain the timer's current expiry time.
+   * Whether the timer has expired or not does not affect this value.
+   */
+  time_point expiry() const
+  {
+    return impl_.get_service().expiry(impl_.get_implementation());
+  }
+
+  /// Set the timer's expiry time as an absolute time.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when expires_at() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_at(const time_point& expiry_time)
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().expires_at(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_at");
+    return s;
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use non-error_code overload.) Set the timer's expiry time as
+  /// an absolute time.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @note If the timer has already expired when expires_at() is called, then
+   * the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_at(const time_point& expiry_time,
+      boost::system::error_code& ec)
+  {
+    return impl_.get_service().expires_at(
+        impl_.get_implementation(), expiry_time, ec);
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  /// Set the timer's expiry time relative to now.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when expires_after() is called,
+   * then the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_after(const duration& expiry_time)
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().expires_after(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_after");
+    return s;
+  }
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+  /// (Deprecated: Use expiry().) Get the timer's expiry time relative to now.
+  /**
+   * This function may be used to obtain the timer's current expiry time.
+   * Whether the timer has expired or not does not affect this value.
+   */
+  duration expires_from_now() const
+  {
+    return impl_.get_service().expires_from_now(impl_.get_implementation());
+  }
+
+  /// (Deprecated: Use expires_after().) Set the timer's expiry time relative
+  /// to now.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   *
+   * @note If the timer has already expired when expires_from_now() is called,
+   * then the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_from_now(const duration& expiry_time)
+  {
+    boost::system::error_code ec;
+    std::size_t s = impl_.get_service().expires_from_now(
+        impl_.get_implementation(), expiry_time, ec);
+    boost::asio::detail::throw_error(ec, "expires_from_now");
+    return s;
+  }
+
+  /// (Deprecated: Use expires_after().) Set the timer's expiry time relative
+  /// to now.
+  /**
+   * This function sets the expiry time. Any pending asynchronous wait
+   * operations will be cancelled. The handler for each cancelled operation will
+   * be invoked with the boost::asio::error::operation_aborted error code.
+   *
+   * @param expiry_time The expiry time to be used for the timer.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   *
+   * @return The number of asynchronous operations that were cancelled.
+   *
+   * @note If the timer has already expired when expires_from_now() is called,
+   * then the handlers for asynchronous wait operations will:
+   *
+   * @li have already been invoked; or
+   *
+   * @li have been queued for invocation in the near future.
+   *
+   * These handlers can no longer be cancelled, and therefore are passed an
+   * error code that indicates the successful completion of the wait operation.
+   */
+  std::size_t expires_from_now(const duration& expiry_time,
+      boost::system::error_code& ec)
+  {
+    return impl_.get_service().expires_from_now(
+        impl_.get_implementation(), expiry_time, ec);
+  }
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  /// Perform a blocking wait on the timer.
+  /**
+   * This function is used to wait for the timer to expire. This function
+   * blocks and does not return until the timer has expired.
+   *
+   * @throws boost::system::system_error Thrown on failure.
+   */
+  void wait()
+  {
+    boost::system::error_code ec;
+    impl_.get_service().wait(impl_.get_implementation(), ec);
+    boost::asio::detail::throw_error(ec, "wait");
+  }
+
+  /// Perform a blocking wait on the timer.
+  /**
+   * This function is used to wait for the timer to expire. This function
+   * blocks and does not return until the timer has expired.
+   *
+   * @param ec Set to indicate what error occurred, if any.
+   */
+  void wait(boost::system::error_code& ec)
+  {
+    impl_.get_service().wait(impl_.get_implementation(), ec);
+  }
+
+  /// Start an asynchronous wait on the timer.
+  /**
+   * This function may be used to initiate an asynchronous wait against the
+   * timer. It always returns immediately.
+   *
+   * For each call to async_wait(), the supplied handler will be called exactly
+   * once. The handler will be called when:
+   *
+   * @li The timer has expired.
+   *
+   * @li The timer was cancelled, in which case the handler is passed the error
+   * code boost::asio::error::operation_aborted.
+   *
+   * @param handler The handler to be called when the timer expires. Copies
+   * will be made of the handler as required. The function signature of the
+   * handler must be:
+   * @code void handler(
+   *   const boost::system::error_code& error // Result of operation.
+   * ); @endcode
+   * Regardless of whether the asynchronous operation completes immediately or
+   * not, the handler will not be invoked from within this function. On
+   * immediate completion, invocation of the handler will be performed in a
+   * manner equivalent to using boost::asio::post().
+   */
+  template <typename WaitHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WaitHandler,
+      void (boost::system::error_code))
+  async_wait(BOOST_ASIO_MOVE_ARG(WaitHandler) handler)
+  {
+    return async_initiate<WaitHandler, void (boost::system::error_code)>(
+        initiate_async_wait(), handler, this);
+  }
+
+private:
+  // Disallow copying and assignment.
+  basic_waitable_timer(const basic_waitable_timer&) BOOST_ASIO_DELETED;
+  basic_waitable_timer& operator=(
+      const basic_waitable_timer&) BOOST_ASIO_DELETED;
+
+  struct initiate_async_wait
+  {
+    template <typename WaitHandler>
+    void operator()(BOOST_ASIO_MOVE_ARG(WaitHandler) handler,
+        basic_waitable_timer* self) const
+    {
+      // If you get an error on the following line it means that your handler
+      // does not meet the documented type requirements for a WaitHandler.
+      BOOST_ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
+
+      detail::non_const_lvalue<WaitHandler> handler2(handler);
+      self->impl_.get_service().async_wait(
+          self->impl_.get_implementation(), handler2.value,
+          self->impl_.get_implementation_executor());
+    }
+  };
+
+  detail::io_object_impl<
+    detail::deadline_timer_service<
+      detail::chrono_time_traits<Clock, WaitTraits> >,
+    executor_type > impl_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_BASIC_WAITABLE_TIMER_HPP

boost/asio/bind_executor.hpp

@@ -0,0 +1,582 @@
+//
+// bind_executor.hpp
+// ~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BIND_EXECUTOR_HPP
+#define BOOST_ASIO_BIND_EXECUTOR_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/detail/variadic_templates.hpp>
+#include <boost/asio/associated_executor.hpp>
+#include <boost/asio/associated_allocator.hpp>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/is_executor.hpp>
+#include <boost/asio/uses_executor.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename T>
+struct executor_binder_check
+{
+  typedef void type;
+};
+
+// Helper to automatically define nested typedef result_type.
+
+template <typename T, typename = void>
+struct executor_binder_result_type
+{
+protected:
+  typedef void result_type_or_void;
+};
+
+template <typename T>
+struct executor_binder_result_type<T,
+  typename executor_binder_check<typename T::result_type>::type>
+{
+  typedef typename T::result_type result_type;
+protected:
+  typedef result_type result_type_or_void;
+};
+
+template <typename R>
+struct executor_binder_result_type<R(*)()>
+{
+  typedef R result_type;
+protected:
+  typedef result_type result_type_or_void;
+};
+
+template <typename R>
+struct executor_binder_result_type<R(&)()>
+{
+  typedef R result_type;
+protected:
+  typedef result_type result_type_or_void;
+};
+
+template <typename R, typename A1>
+struct executor_binder_result_type<R(*)(A1)>
+{
+  typedef R result_type;
+protected:
+  typedef result_type result_type_or_void;
+};
+
+template <typename R, typename A1>
+struct executor_binder_result_type<R(&)(A1)>
+{
+  typedef R result_type;
+protected:
+  typedef result_type result_type_or_void;
+};
+
+template <typename R, typename A1, typename A2>
+struct executor_binder_result_type<R(*)(A1, A2)>
+{
+  typedef R result_type;
+protected:
+  typedef result_type result_type_or_void;
+};
+
+template <typename R, typename A1, typename A2>
+struct executor_binder_result_type<R(&)(A1, A2)>
+{
+  typedef R result_type;
+protected:
+  typedef result_type result_type_or_void;
+};
+
+// Helper to automatically define nested typedef argument_type.
+
+template <typename T, typename = void>
+struct executor_binder_argument_type {};
+
+template <typename T>
+struct executor_binder_argument_type<T,
+  typename executor_binder_check<typename T::argument_type>::type>
+{
+  typedef typename T::argument_type argument_type;
+};
+
+template <typename R, typename A1>
+struct executor_binder_argument_type<R(*)(A1)>
+{
+  typedef A1 argument_type;
+};
+
+template <typename R, typename A1>
+struct executor_binder_argument_type<R(&)(A1)>
+{
+  typedef A1 argument_type;
+};
+
+// Helper to automatically define nested typedefs first_argument_type and
+// second_argument_type.
+
+template <typename T, typename = void>
+struct executor_binder_argument_types {};
+
+template <typename T>
+struct executor_binder_argument_types<T,
+  typename executor_binder_check<typename T::first_argument_type>::type>
+{
+  typedef typename T::first_argument_type first_argument_type;
+  typedef typename T::second_argument_type second_argument_type;
+};
+
+template <typename R, typename A1, typename A2>
+struct executor_binder_argument_type<R(*)(A1, A2)>
+{
+  typedef A1 first_argument_type;
+  typedef A2 second_argument_type;
+};
+
+template <typename R, typename A1, typename A2>
+struct executor_binder_argument_type<R(&)(A1, A2)>
+{
+  typedef A1 first_argument_type;
+  typedef A2 second_argument_type;
+};
+
+// Helper to:
+// - Apply the empty base optimisation to the executor.
+// - Perform uses_executor construction of the target type, if required.
+
+template <typename T, typename Executor, bool UsesExecutor>
+class executor_binder_base;
+
+template <typename T, typename Executor>
+class executor_binder_base<T, Executor, true>
+  : protected Executor
+{
+protected:
+  template <typename E, typename U>
+  executor_binder_base(BOOST_ASIO_MOVE_ARG(E) e, BOOST_ASIO_MOVE_ARG(U) u)
+    : executor_(BOOST_ASIO_MOVE_CAST(E)(e)),
+      target_(executor_arg_t(), executor_, BOOST_ASIO_MOVE_CAST(U)(u))
+  {
+  }
+
+  Executor executor_;
+  T target_;
+};
+
+template <typename T, typename Executor>
+class executor_binder_base<T, Executor, false>
+{
+protected:
+  template <typename E, typename U>
+  executor_binder_base(BOOST_ASIO_MOVE_ARG(E) e, BOOST_ASIO_MOVE_ARG(U) u)
+    : executor_(BOOST_ASIO_MOVE_CAST(E)(e)),
+      target_(BOOST_ASIO_MOVE_CAST(U)(u))
+  {
+  }
+
+  Executor executor_;
+  T target_;
+};
+
+// Helper to enable SFINAE on zero-argument operator() below.
+
+template <typename T, typename = void>
+struct executor_binder_result_of0
+{
+  typedef void type;
+};
+
+template <typename T>
+struct executor_binder_result_of0<T,
+  typename executor_binder_check<typename result_of<T()>::type>::type>
+{
+  typedef typename result_of<T()>::type type;
+};
+
+} // namespace detail
+
+/// A call wrapper type to bind an executor of type @c Executor to an object of
+/// type @c T.
+template <typename T, typename Executor>
+class executor_binder
+#if !defined(GENERATING_DOCUMENTATION)
+  : public detail::executor_binder_result_type<T>,
+    public detail::executor_binder_argument_type<T>,
+    public detail::executor_binder_argument_types<T>,
+    private detail::executor_binder_base<
+      T, Executor, uses_executor<T, Executor>::value>
+#endif // !defined(GENERATING_DOCUMENTATION)
+{
+public:
+  /// The type of the target object.
+  typedef T target_type;
+
+  /// The type of the associated executor.
+  typedef Executor executor_type;
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// The return type if a function.
+  /**
+   * The type of @c result_type is based on the type @c T of the wrapper's
+   * target object:
+   *
+   * @li if @c T is a pointer to function type, @c result_type is a synonym for
+   * the return type of @c T;
+   *
+   * @li if @c T is a class type with a member type @c result_type, then @c
+   * result_type is a synonym for @c T::result_type;
+   *
+   * @li otherwise @c result_type is not defined.
+   */
+  typedef see_below result_type;
+
+  /// The type of the function's argument.
+  /**
+   * The type of @c argument_type is based on the type @c T of the wrapper's
+   * target object:
+   *
+   * @li if @c T is a pointer to a function type accepting a single argument,
+   * @c argument_type is a synonym for the return type of @c T;
+   *
+   * @li if @c T is a class type with a member type @c argument_type, then @c
+   * argument_type is a synonym for @c T::argument_type;
+   *
+   * @li otherwise @c argument_type is not defined.
+   */
+  typedef see_below argument_type;
+
+  /// The type of the function's first argument.
+  /**
+   * The type of @c first_argument_type is based on the type @c T of the
+   * wrapper's target object:
+   *
+   * @li if @c T is a pointer to a function type accepting two arguments, @c
+   * first_argument_type is a synonym for the return type of @c T;
+   *
+   * @li if @c T is a class type with a member type @c first_argument_type,
+   * then @c first_argument_type is a synonym for @c T::first_argument_type;
+   *
+   * @li otherwise @c first_argument_type is not defined.
+   */
+  typedef see_below first_argument_type;
+
+  /// The type of the function's second argument.
+  /**
+   * The type of @c second_argument_type is based on the type @c T of the
+   * wrapper's target object:
+   *
+   * @li if @c T is a pointer to a function type accepting two arguments, @c
+   * second_argument_type is a synonym for the return type of @c T;
+   *
+   * @li if @c T is a class type with a member type @c first_argument_type,
+   * then @c second_argument_type is a synonym for @c T::second_argument_type;
+   *
+   * @li otherwise @c second_argument_type is not defined.
+   */
+  typedef see_below second_argument_type;
+#endif // defined(GENERATING_DOCUMENTATION)
+
+  /// Construct an executor wrapper for the specified object.
+  /**
+   * This constructor is only valid if the type @c T is constructible from type
+   * @c U.
+   */
+  template <typename U>
+  executor_binder(executor_arg_t, const executor_type& e,
+      BOOST_ASIO_MOVE_ARG(U) u)
+    : base_type(e, BOOST_ASIO_MOVE_CAST(U)(u))
+  {
+  }
+
+  /// Copy constructor.
+  executor_binder(const executor_binder& other)
+    : base_type(other.get_executor(), other.get())
+  {
+  }
+
+  /// Construct a copy, but specify a different executor.
+  executor_binder(executor_arg_t, const executor_type& e,
+      const executor_binder& other)
+    : base_type(e, other.get())
+  {
+  }
+
+  /// Construct a copy of a different executor wrapper type.
+  /**
+   * This constructor is only valid if the @c Executor type is constructible
+   * from type @c OtherExecutor, and the type @c T is constructible from type
+   * @c U.
+   */
+  template <typename U, typename OtherExecutor>
+  executor_binder(const executor_binder<U, OtherExecutor>& other)
+    : base_type(other.get_executor(), other.get())
+  {
+  }
+
+  /// Construct a copy of a different executor wrapper type, but specify a
+  /// different executor.
+  /**
+   * This constructor is only valid if the type @c T is constructible from type
+   * @c U.
+   */
+  template <typename U, typename OtherExecutor>
+  executor_binder(executor_arg_t, const executor_type& e,
+      const executor_binder<U, OtherExecutor>& other)
+    : base_type(e, other.get())
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Move constructor.
+  executor_binder(executor_binder&& other)
+    : base_type(BOOST_ASIO_MOVE_CAST(executor_type)(other.get_executor()),
+        BOOST_ASIO_MOVE_CAST(T)(other.get()))
+  {
+  }
+
+  /// Move construct the target object, but specify a different executor.
+  executor_binder(executor_arg_t, const executor_type& e,
+      executor_binder&& other)
+    : base_type(e, BOOST_ASIO_MOVE_CAST(T)(other.get()))
+  {
+  }
+
+  /// Move construct from a different executor wrapper type.
+  template <typename U, typename OtherExecutor>
+  executor_binder(executor_binder<U, OtherExecutor>&& other)
+    : base_type(BOOST_ASIO_MOVE_CAST(OtherExecutor)(other.get_executor()),
+        BOOST_ASIO_MOVE_CAST(U)(other.get()))
+  {
+  }
+
+  /// Move construct from a different executor wrapper type, but specify a
+  /// different executor.
+  template <typename U, typename OtherExecutor>
+  executor_binder(executor_arg_t, const executor_type& e,
+      executor_binder<U, OtherExecutor>&& other)
+    : base_type(e, BOOST_ASIO_MOVE_CAST(U)(other.get()))
+  {
+  }
+
+#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
+
+  /// Destructor.
+  ~executor_binder()
+  {
+  }
+
+  /// Obtain a reference to the target object.
+  target_type& get() BOOST_ASIO_NOEXCEPT
+  {
+    return this->target_;
+  }
+
+  /// Obtain a reference to the target object.
+  const target_type& get() const BOOST_ASIO_NOEXCEPT
+  {
+    return this->target_;
+  }
+
+  /// Obtain the associated executor.
+  executor_type get_executor() const BOOST_ASIO_NOEXCEPT
+  {
+    return this->executor_;
+  }
+
+#if defined(GENERATING_DOCUMENTATION)
+
+  template <typename... Args> auto operator()(Args&& ...);
+  template <typename... Args> auto operator()(Args&& ...) const;
+
+#elif defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+
+  /// Forwarding function call operator.
+  template <typename... Args>
+  typename result_of<T(Args...)>::type operator()(
+      BOOST_ASIO_MOVE_ARG(Args)... args)
+  {
+    return this->target_(BOOST_ASIO_MOVE_CAST(Args)(args)...);
+  }
+
+  /// Forwarding function call operator.
+  template <typename... Args>
+  typename result_of<T(Args...)>::type operator()(
+      BOOST_ASIO_MOVE_ARG(Args)... args) const
+  {
+    return this->target_(BOOST_ASIO_MOVE_CAST(Args)(args)...);
+  }
+
+#elif defined(BOOST_ASIO_HAS_STD_TYPE_TRAITS) && !defined(_MSC_VER)
+
+  typename detail::executor_binder_result_of0<T>::type operator()()
+  {
+    return this->target_();
+  }
+
+  typename detail::executor_binder_result_of0<T>::type operator()() const
+  {
+    return this->target_();
+  }
+
+#define BOOST_ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF(n) \
+  template <BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  typename result_of<T(BOOST_ASIO_VARIADIC_TARGS(n))>::type operator()( \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n)) \
+  { \
+    return this->target_(BOOST_ASIO_VARIADIC_MOVE_ARGS(n)); \
+  } \
+  \
+  template <BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  typename result_of<T(BOOST_ASIO_VARIADIC_TARGS(n))>::type operator()( \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n)) const \
+  { \
+    return this->target_(BOOST_ASIO_VARIADIC_MOVE_ARGS(n)); \
+  } \
+  /**/
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF)
+#undef BOOST_ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF
+
+#else // defined(BOOST_ASIO_HAS_STD_TYPE_TRAITS) && !defined(_MSC_VER)
+
+  typedef typename detail::executor_binder_result_type<T>::result_type_or_void
+    result_type_or_void;
+
+  result_type_or_void operator()()
+  {
+    return this->target_();
+  }
+
+  result_type_or_void operator()() const
+  {
+    return this->target_();
+  }
+
+#define BOOST_ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF(n) \
+  template <BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  result_type_or_void operator()( \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n)) \
+  { \
+    return this->target_(BOOST_ASIO_VARIADIC_MOVE_ARGS(n)); \
+  } \
+  \
+  template <BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  result_type_or_void operator()( \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n)) const \
+  { \
+    return this->target_(BOOST_ASIO_VARIADIC_MOVE_ARGS(n)); \
+  } \
+  /**/
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF)
+#undef BOOST_ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF
+
+#endif // defined(BOOST_ASIO_HAS_STD_TYPE_TRAITS) && !defined(_MSC_VER)
+
+private:
+  typedef detail::executor_binder_base<T, Executor,
+    uses_executor<T, Executor>::value> base_type;
+};
+
+/// Associate an object of type @c T with an executor of type @c Executor.
+template <typename Executor, typename T>
+inline executor_binder<typename decay<T>::type, Executor>
+bind_executor(const Executor& ex, BOOST_ASIO_MOVE_ARG(T) t,
+    typename enable_if<is_executor<Executor>::value>::type* = 0)
+{
+  return executor_binder<typename decay<T>::type, Executor>(
+      executor_arg_t(), ex, BOOST_ASIO_MOVE_CAST(T)(t));
+}
+
+/// Associate an object of type @c T with an execution context's executor.
+template <typename ExecutionContext, typename T>
+inline executor_binder<typename decay<T>::type,
+  typename ExecutionContext::executor_type>
+bind_executor(ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(T) t,
+    typename enable_if<is_convertible<
+      ExecutionContext&, execution_context&>::value>::type* = 0)
+{
+  return executor_binder<typename decay<T>::type,
+    typename ExecutionContext::executor_type>(
+      executor_arg_t(), ctx.get_executor(), BOOST_ASIO_MOVE_CAST(T)(t));
+}
+
+#if !defined(GENERATING_DOCUMENTATION)
+
+template <typename T, typename Executor>
+struct uses_executor<executor_binder<T, Executor>, Executor>
+  : true_type {};
+
+template <typename T, typename Executor, typename Signature>
+class async_result<executor_binder<T, Executor>, Signature>
+{
+public:
+  typedef executor_binder<
+    typename async_result<T, Signature>::completion_handler_type, Executor>
+      completion_handler_type;
+
+  typedef typename async_result<T, Signature>::return_type return_type;
+
+  explicit async_result(executor_binder<T, Executor>& b)
+    : target_(b.get())
+  {
+  }
+
+  return_type get()
+  {
+    return target_.get();
+  }
+
+private:
+  async_result(const async_result&) BOOST_ASIO_DELETED;
+  async_result& operator=(const async_result&) BOOST_ASIO_DELETED;
+
+  async_result<T, Signature> target_;
+};
+
+template <typename T, typename Executor, typename Allocator>
+struct associated_allocator<executor_binder<T, Executor>, Allocator>
+{
+  typedef typename associated_allocator<T, Allocator>::type type;
+
+  static type get(const executor_binder<T, Executor>& b,
+      const Allocator& a = Allocator()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_allocator<T, Allocator>::get(b.get(), a);
+  }
+};
+
+template <typename T, typename Executor, typename Executor1>
+struct associated_executor<executor_binder<T, Executor>, Executor1>
+{
+  typedef Executor type;
+
+  static type get(const executor_binder<T, Executor>& b,
+      const Executor1& = Executor1()) BOOST_ASIO_NOEXCEPT
+  {
+    return b.get_executor();
+  }
+};
+
+#endif // !defined(GENERATING_DOCUMENTATION)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_BIND_EXECUTOR_HPP

boost/asio/buffered_read_stream.hpp

@@ -0,0 +1,242 @@
+//
+// buffered_read_stream.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BUFFERED_READ_STREAM_HPP
+#define BOOST_ASIO_BUFFERED_READ_STREAM_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/buffered_read_stream_fwd.hpp>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/detail/bind_handler.hpp>
+#include <boost/asio/detail/buffer_resize_guard.hpp>
+#include <boost/asio/detail/buffered_stream_storage.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/error.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Adds buffering to the read-related operations of a stream.
+/**
+ * The buffered_read_stream class template can be used to add buffering to the
+ * synchronous and asynchronous read operations of a stream.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ *
+ * @par Concepts:
+ * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
+ */
+template <typename Stream>
+class buffered_read_stream
+  : private noncopyable
+{
+public:
+  /// The type of the next layer.
+  typedef typename remove_reference<Stream>::type next_layer_type;
+
+  /// The type of the lowest layer.
+  typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
+
+  /// The type of the executor associated with the object.
+  typedef typename lowest_layer_type::executor_type executor_type;
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// The default buffer size.
+  static const std::size_t default_buffer_size = implementation_defined;
+#else
+  BOOST_ASIO_STATIC_CONSTANT(std::size_t, default_buffer_size = 1024);
+#endif
+
+  /// Construct, passing the specified argument to initialise the next layer.
+  template <typename Arg>
+  explicit buffered_read_stream(Arg& a)
+    : next_layer_(a),
+      storage_(default_buffer_size)
+  {
+  }
+
+  /// Construct, passing the specified argument to initialise the next layer.
+  template <typename Arg>
+  buffered_read_stream(Arg& a, std::size_t buffer_size)
+    : next_layer_(a),
+      storage_(buffer_size)
+  {
+  }
+
+  /// Get a reference to the next layer.
+  next_layer_type& next_layer()
+  {
+    return next_layer_;
+  }
+
+  /// Get a reference to the lowest layer.
+  lowest_layer_type& lowest_layer()
+  {
+    return next_layer_.lowest_layer();
+  }
+
+  /// Get a const reference to the lowest layer.
+  const lowest_layer_type& lowest_layer() const
+  {
+    return next_layer_.lowest_layer();
+  }
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return next_layer_.lowest_layer().get_executor();
+  }
+
+  /// Close the stream.
+  void close()
+  {
+    next_layer_.close();
+  }
+
+  /// Close the stream.
+  BOOST_ASIO_SYNC_OP_VOID close(boost::system::error_code& ec)
+  {
+    next_layer_.close(ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Write the given data to the stream. Returns the number of bytes written.
+  /// Throws an exception on failure.
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers)
+  {
+    return next_layer_.write_some(buffers);
+  }
+
+  /// Write the given data to the stream. Returns the number of bytes written,
+  /// or 0 if an error occurred.
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return next_layer_.write_some(buffers, ec);
+  }
+
+  /// Start an asynchronous write. The data being written must be valid for the
+  /// lifetime of the asynchronous operation.
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_write_some(const ConstBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return next_layer_.async_write_some(buffers,
+        BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
+  }
+
+  /// Fill the buffer with some data. Returns the number of bytes placed in the
+  /// buffer as a result of the operation. Throws an exception on failure.
+  std::size_t fill();
+
+  /// Fill the buffer with some data. Returns the number of bytes placed in the
+  /// buffer as a result of the operation, or 0 if an error occurred.
+  std::size_t fill(boost::system::error_code& ec);
+
+  /// Start an asynchronous fill.
+  template <typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_fill(BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
+
+  /// Read some data from the stream. Returns the number of bytes read. Throws
+  /// an exception on failure.
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers);
+
+  /// Read some data from the stream. Returns the number of bytes read or 0 if
+  /// an error occurred.
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec);
+
+  /// Start an asynchronous read. The buffer into which the data will be read
+  /// must be valid for the lifetime of the asynchronous operation.
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_read_some(const MutableBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
+
+  /// Peek at the incoming data on the stream. Returns the number of bytes read.
+  /// Throws an exception on failure.
+  template <typename MutableBufferSequence>
+  std::size_t peek(const MutableBufferSequence& buffers);
+
+  /// Peek at the incoming data on the stream. Returns the number of bytes read,
+  /// or 0 if an error occurred.
+  template <typename MutableBufferSequence>
+  std::size_t peek(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec);
+
+  /// Determine the amount of data that may be read without blocking.
+  std::size_t in_avail()
+  {
+    return storage_.size();
+  }
+
+  /// Determine the amount of data that may be read without blocking.
+  std::size_t in_avail(boost::system::error_code& ec)
+  {
+    ec = boost::system::error_code();
+    return storage_.size();
+  }
+
+private:
+  /// Copy data out of the internal buffer to the specified target buffer.
+  /// Returns the number of bytes copied.
+  template <typename MutableBufferSequence>
+  std::size_t copy(const MutableBufferSequence& buffers)
+  {
+    std::size_t bytes_copied = boost::asio::buffer_copy(
+        buffers, storage_.data(), storage_.size());
+    storage_.consume(bytes_copied);
+    return bytes_copied;
+  }
+
+  /// Copy data from the internal buffer to the specified target buffer, without
+  /// removing the data from the internal buffer. Returns the number of bytes
+  /// copied.
+  template <typename MutableBufferSequence>
+  std::size_t peek_copy(const MutableBufferSequence& buffers)
+  {
+    return boost::asio::buffer_copy(buffers, storage_.data(), storage_.size());
+  }
+
+  /// The next layer.
+  Stream next_layer_;
+
+  // The data in the buffer.
+  detail::buffered_stream_storage storage_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/impl/buffered_read_stream.hpp>
+
+#endif // BOOST_ASIO_BUFFERED_READ_STREAM_HPP

boost/asio/buffered_read_stream_fwd.hpp

@@ -0,0 +1,27 @@
+//
+// buffered_read_stream_fwd.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BUFFERED_READ_STREAM_FWD_HPP
+#define BOOST_ASIO_BUFFERED_READ_STREAM_FWD_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+namespace boost {
+namespace asio {
+
+template <typename Stream>
+class buffered_read_stream;
+
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_BUFFERED_READ_STREAM_FWD_HPP

boost/asio/buffered_stream.hpp

@@ -0,0 +1,263 @@
+//
+// buffered_stream.hpp
+// ~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BUFFERED_STREAM_HPP
+#define BOOST_ASIO_BUFFERED_STREAM_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/buffered_read_stream.hpp>
+#include <boost/asio/buffered_write_stream.hpp>
+#include <boost/asio/buffered_stream_fwd.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/error.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Adds buffering to the read- and write-related operations of a stream.
+/**
+ * The buffered_stream class template can be used to add buffering to the
+ * synchronous and asynchronous read and write operations of a stream.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ *
+ * @par Concepts:
+ * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
+ */
+template <typename Stream>
+class buffered_stream
+  : private noncopyable
+{
+public:
+  /// The type of the next layer.
+  typedef typename remove_reference<Stream>::type next_layer_type;
+
+  /// The type of the lowest layer.
+  typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
+
+  /// The type of the executor associated with the object.
+  typedef typename lowest_layer_type::executor_type executor_type;
+
+  /// Construct, passing the specified argument to initialise the next layer.
+  template <typename Arg>
+  explicit buffered_stream(Arg& a)
+    : inner_stream_impl_(a),
+      stream_impl_(inner_stream_impl_)
+  {
+  }
+
+  /// Construct, passing the specified argument to initialise the next layer.
+  template <typename Arg>
+  explicit buffered_stream(Arg& a, std::size_t read_buffer_size,
+      std::size_t write_buffer_size)
+    : inner_stream_impl_(a, write_buffer_size),
+      stream_impl_(inner_stream_impl_, read_buffer_size)
+  {
+  }
+
+  /// Get a reference to the next layer.
+  next_layer_type& next_layer()
+  {
+    return stream_impl_.next_layer().next_layer();
+  }
+
+  /// Get a reference to the lowest layer.
+  lowest_layer_type& lowest_layer()
+  {
+    return stream_impl_.lowest_layer();
+  }
+
+  /// Get a const reference to the lowest layer.
+  const lowest_layer_type& lowest_layer() const
+  {
+    return stream_impl_.lowest_layer();
+  }
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return stream_impl_.lowest_layer().get_executor();
+  }
+
+  /// Close the stream.
+  void close()
+  {
+    stream_impl_.close();
+  }
+
+  /// Close the stream.
+  BOOST_ASIO_SYNC_OP_VOID close(boost::system::error_code& ec)
+  {
+    stream_impl_.close(ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Flush all data from the buffer to the next layer. Returns the number of
+  /// bytes written to the next layer on the last write operation. Throws an
+  /// exception on failure.
+  std::size_t flush()
+  {
+    return stream_impl_.next_layer().flush();
+  }
+
+  /// Flush all data from the buffer to the next layer. Returns the number of
+  /// bytes written to the next layer on the last write operation, or 0 if an
+  /// error occurred.
+  std::size_t flush(boost::system::error_code& ec)
+  {
+    return stream_impl_.next_layer().flush(ec);
+  }
+
+  /// Start an asynchronous flush.
+  template <typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_flush(BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return stream_impl_.next_layer().async_flush(
+        BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
+  }
+
+  /// Write the given data to the stream. Returns the number of bytes written.
+  /// Throws an exception on failure.
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers)
+  {
+    return stream_impl_.write_some(buffers);
+  }
+
+  /// Write the given data to the stream. Returns the number of bytes written,
+  /// or 0 if an error occurred.
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return stream_impl_.write_some(buffers, ec);
+  }
+
+  /// Start an asynchronous write. The data being written must be valid for the
+  /// lifetime of the asynchronous operation.
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_write_some(const ConstBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
+  {
+    return stream_impl_.async_write_some(buffers,
+        BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
+  }
+
+  /// Fill the buffer with some data. Returns the number of bytes placed in the
+  /// buffer as a result of the operation. Throws an exception on failure.
+  std::size_t fill()
+  {
+    return stream_impl_.fill();
+  }
+
+  /// Fill the buffer with some data. Returns the number of bytes placed in the
+  /// buffer as a result of the operation, or 0 if an error occurred.
+  std::size_t fill(boost::system::error_code& ec)
+  {
+    return stream_impl_.fill(ec);
+  }
+
+  /// Start an asynchronous fill.
+  template <typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_fill(BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return stream_impl_.async_fill(BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
+  }
+
+  /// Read some data from the stream. Returns the number of bytes read. Throws
+  /// an exception on failure.
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers)
+  {
+    return stream_impl_.read_some(buffers);
+  }
+
+  /// Read some data from the stream. Returns the number of bytes read or 0 if
+  /// an error occurred.
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return stream_impl_.read_some(buffers, ec);
+  }
+
+  /// Start an asynchronous read. The buffer into which the data will be read
+  /// must be valid for the lifetime of the asynchronous operation.
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_read_some(const MutableBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return stream_impl_.async_read_some(buffers,
+        BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
+  }
+
+  /// Peek at the incoming data on the stream. Returns the number of bytes read.
+  /// Throws an exception on failure.
+  template <typename MutableBufferSequence>
+  std::size_t peek(const MutableBufferSequence& buffers)
+  {
+    return stream_impl_.peek(buffers);
+  }
+
+  /// Peek at the incoming data on the stream. Returns the number of bytes read,
+  /// or 0 if an error occurred.
+  template <typename MutableBufferSequence>
+  std::size_t peek(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return stream_impl_.peek(buffers, ec);
+  }
+
+  /// Determine the amount of data that may be read without blocking.
+  std::size_t in_avail()
+  {
+    return stream_impl_.in_avail();
+  }
+
+  /// Determine the amount of data that may be read without blocking.
+  std::size_t in_avail(boost::system::error_code& ec)
+  {
+    return stream_impl_.in_avail(ec);
+  }
+
+private:
+  // The buffered write stream.
+  typedef buffered_write_stream<Stream> write_stream_type;
+  write_stream_type inner_stream_impl_;
+
+  // The buffered read stream.
+  typedef buffered_read_stream<write_stream_type&> read_stream_type;
+  read_stream_type stream_impl_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_BUFFERED_STREAM_HPP

boost/asio/buffered_stream_fwd.hpp

@@ -0,0 +1,27 @@
+//
+// buffered_stream_fwd.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BUFFERED_STREAM_FWD_HPP
+#define BOOST_ASIO_BUFFERED_STREAM_FWD_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+namespace boost {
+namespace asio {
+
+template <typename Stream>
+class buffered_stream;
+
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_BUFFERED_STREAM_FWD_HPP

boost/asio/buffered_write_stream.hpp

@@ -0,0 +1,234 @@
+//
+// buffered_write_stream.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BUFFERED_WRITE_STREAM_HPP
+#define BOOST_ASIO_BUFFERED_WRITE_STREAM_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/buffered_write_stream_fwd.hpp>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/completion_condition.hpp>
+#include <boost/asio/detail/bind_handler.hpp>
+#include <boost/asio/detail/buffered_stream_storage.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/write.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Adds buffering to the write-related operations of a stream.
+/**
+ * The buffered_write_stream class template can be used to add buffering to the
+ * synchronous and asynchronous write operations of a stream.
+ *
+ * @par Thread Safety
+ * @e Distinct @e objects: Safe.@n
+ * @e Shared @e objects: Unsafe.
+ *
+ * @par Concepts:
+ * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
+ */
+template <typename Stream>
+class buffered_write_stream
+  : private noncopyable
+{
+public:
+  /// The type of the next layer.
+  typedef typename remove_reference<Stream>::type next_layer_type;
+
+  /// The type of the lowest layer.
+  typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
+
+  /// The type of the executor associated with the object.
+  typedef typename lowest_layer_type::executor_type executor_type;
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// The default buffer size.
+  static const std::size_t default_buffer_size = implementation_defined;
+#else
+  BOOST_ASIO_STATIC_CONSTANT(std::size_t, default_buffer_size = 1024);
+#endif
+
+  /// Construct, passing the specified argument to initialise the next layer.
+  template <typename Arg>
+  explicit buffered_write_stream(Arg& a)
+    : next_layer_(a),
+      storage_(default_buffer_size)
+  {
+  }
+
+  /// Construct, passing the specified argument to initialise the next layer.
+  template <typename Arg>
+  buffered_write_stream(Arg& a, std::size_t buffer_size)
+    : next_layer_(a),
+      storage_(buffer_size)
+  {
+  }
+
+  /// Get a reference to the next layer.
+  next_layer_type& next_layer()
+  {
+    return next_layer_;
+  }
+
+  /// Get a reference to the lowest layer.
+  lowest_layer_type& lowest_layer()
+  {
+    return next_layer_.lowest_layer();
+  }
+
+  /// Get a const reference to the lowest layer.
+  const lowest_layer_type& lowest_layer() const
+  {
+    return next_layer_.lowest_layer();
+  }
+
+  /// Get the executor associated with the object.
+  executor_type get_executor() BOOST_ASIO_NOEXCEPT
+  {
+    return next_layer_.lowest_layer().get_executor();
+  }
+
+  /// Close the stream.
+  void close()
+  {
+    next_layer_.close();
+  }
+
+  /// Close the stream.
+  BOOST_ASIO_SYNC_OP_VOID close(boost::system::error_code& ec)
+  {
+    next_layer_.close(ec);
+    BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
+  }
+
+  /// Flush all data from the buffer to the next layer. Returns the number of
+  /// bytes written to the next layer on the last write operation. Throws an
+  /// exception on failure.
+  std::size_t flush();
+
+  /// Flush all data from the buffer to the next layer. Returns the number of
+  /// bytes written to the next layer on the last write operation, or 0 if an
+  /// error occurred.
+  std::size_t flush(boost::system::error_code& ec);
+
+  /// Start an asynchronous flush.
+  template <typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_flush(BOOST_ASIO_MOVE_ARG(WriteHandler) handler);
+
+  /// Write the given data to the stream. Returns the number of bytes written.
+  /// Throws an exception on failure.
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers);
+
+  /// Write the given data to the stream. Returns the number of bytes written,
+  /// or 0 if an error occurred and the error handler did not throw.
+  template <typename ConstBufferSequence>
+  std::size_t write_some(const ConstBufferSequence& buffers,
+      boost::system::error_code& ec);
+
+  /// Start an asynchronous write. The data being written must be valid for the
+  /// lifetime of the asynchronous operation.
+  template <typename ConstBufferSequence, typename WriteHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
+      void (boost::system::error_code, std::size_t))
+  async_write_some(const ConstBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(WriteHandler) handler);
+
+  /// Read some data from the stream. Returns the number of bytes read. Throws
+  /// an exception on failure.
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers)
+  {
+    return next_layer_.read_some(buffers);
+  }
+
+  /// Read some data from the stream. Returns the number of bytes read or 0 if
+  /// an error occurred.
+  template <typename MutableBufferSequence>
+  std::size_t read_some(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return next_layer_.read_some(buffers, ec);
+  }
+
+  /// Start an asynchronous read. The buffer into which the data will be read
+  /// must be valid for the lifetime of the asynchronous operation.
+  template <typename MutableBufferSequence, typename ReadHandler>
+  BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
+      void (boost::system::error_code, std::size_t))
+  async_read_some(const MutableBufferSequence& buffers,
+      BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
+  {
+    return next_layer_.async_read_some(buffers,
+        BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
+  }
+
+  /// Peek at the incoming data on the stream. Returns the number of bytes read.
+  /// Throws an exception on failure.
+  template <typename MutableBufferSequence>
+  std::size_t peek(const MutableBufferSequence& buffers)
+  {
+    return next_layer_.peek(buffers);
+  }
+
+  /// Peek at the incoming data on the stream. Returns the number of bytes read,
+  /// or 0 if an error occurred.
+  template <typename MutableBufferSequence>
+  std::size_t peek(const MutableBufferSequence& buffers,
+      boost::system::error_code& ec)
+  {
+    return next_layer_.peek(buffers, ec);
+  }
+
+  /// Determine the amount of data that may be read without blocking.
+  std::size_t in_avail()
+  {
+    return next_layer_.in_avail();
+  }
+
+  /// Determine the amount of data that may be read without blocking.
+  std::size_t in_avail(boost::system::error_code& ec)
+  {
+    return next_layer_.in_avail(ec);
+  }
+
+private:
+  /// Copy data into the internal buffer from the specified source buffer.
+  /// Returns the number of bytes copied.
+  template <typename ConstBufferSequence>
+  std::size_t copy(const ConstBufferSequence& buffers);
+
+  /// The next layer.
+  Stream next_layer_;
+
+  // The data in the buffer.
+  detail::buffered_stream_storage storage_;
+};
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/impl/buffered_write_stream.hpp>
+
+#endif // BOOST_ASIO_BUFFERED_WRITE_STREAM_HPP

boost/asio/buffered_write_stream_fwd.hpp

@@ -0,0 +1,27 @@
+//
+// buffered_write_stream_fwd.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BUFFERED_WRITE_STREAM_FWD_HPP
+#define BOOST_ASIO_BUFFERED_WRITE_STREAM_FWD_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+namespace boost {
+namespace asio {
+
+template <typename Stream>
+class buffered_write_stream;
+
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_BUFFERED_WRITE_STREAM_FWD_HPP

boost/asio/buffers_iterator.hpp

@@ -0,0 +1,523 @@
+//
+// buffers_iterator.hpp
+// ~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_BUFFERS_ITERATOR_HPP
+#define BOOST_ASIO_BUFFERS_ITERATOR_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <iterator>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/detail/assert.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+namespace detail
+{
+  template <bool IsMutable>
+  struct buffers_iterator_types_helper;
+
+  template <>
+  struct buffers_iterator_types_helper<false>
+  {
+    typedef const_buffer buffer_type;
+    template <typename ByteType>
+    struct byte_type
+    {
+      typedef typename add_const<ByteType>::type type;
+    };
+  };
+
+  template <>
+  struct buffers_iterator_types_helper<true>
+  {
+    typedef mutable_buffer buffer_type;
+    template <typename ByteType>
+    struct byte_type
+    {
+      typedef ByteType type;
+    };
+  };
+
+  template <typename BufferSequence, typename ByteType>
+  struct buffers_iterator_types
+  {
+    enum
+    {
+      is_mutable = is_convertible<
+          typename BufferSequence::value_type,
+          mutable_buffer>::value
+    };
+    typedef buffers_iterator_types_helper<is_mutable> helper;
+    typedef typename helper::buffer_type buffer_type;
+    typedef typename helper::template byte_type<ByteType>::type byte_type;
+    typedef typename BufferSequence::const_iterator const_iterator;
+  };
+
+  template <typename ByteType>
+  struct buffers_iterator_types<mutable_buffer, ByteType>
+  {
+    typedef mutable_buffer buffer_type;
+    typedef ByteType byte_type;
+    typedef const mutable_buffer* const_iterator;
+  };
+
+  template <typename ByteType>
+  struct buffers_iterator_types<const_buffer, ByteType>
+  {
+    typedef const_buffer buffer_type;
+    typedef typename add_const<ByteType>::type byte_type;
+    typedef const const_buffer* const_iterator;
+  };
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+
+  template <typename ByteType>
+  struct buffers_iterator_types<mutable_buffers_1, ByteType>
+  {
+    typedef mutable_buffer buffer_type;
+    typedef ByteType byte_type;
+    typedef const mutable_buffer* const_iterator;
+  };
+
+  template <typename ByteType>
+  struct buffers_iterator_types<const_buffers_1, ByteType>
+  {
+    typedef const_buffer buffer_type;
+    typedef typename add_const<ByteType>::type byte_type;
+    typedef const const_buffer* const_iterator;
+  };
+
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+}
+
+/// A random access iterator over the bytes in a buffer sequence.
+template <typename BufferSequence, typename ByteType = char>
+class buffers_iterator
+{
+private:
+  typedef typename detail::buffers_iterator_types<
+      BufferSequence, ByteType>::buffer_type buffer_type;
+
+  typedef typename detail::buffers_iterator_types<BufferSequence,
+          ByteType>::const_iterator buffer_sequence_iterator_type;
+
+public:
+  /// The type used for the distance between two iterators.
+  typedef std::ptrdiff_t difference_type;
+
+  /// The type of the value pointed to by the iterator.
+  typedef ByteType value_type;
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// The type of the result of applying operator->() to the iterator.
+  /**
+   * If the buffer sequence stores buffer objects that are convertible to
+   * mutable_buffer, this is a pointer to a non-const ByteType. Otherwise, a
+   * pointer to a const ByteType.
+   */
+  typedef const_or_non_const_ByteType* pointer;
+#else // defined(GENERATING_DOCUMENTATION)
+  typedef typename detail::buffers_iterator_types<
+      BufferSequence, ByteType>::byte_type* pointer;
+#endif // defined(GENERATING_DOCUMENTATION)
+
+#if defined(GENERATING_DOCUMENTATION)
+  /// The type of the result of applying operator*() to the iterator.
+  /**
+   * If the buffer sequence stores buffer objects that are convertible to
+   * mutable_buffer, this is a reference to a non-const ByteType. Otherwise, a
+   * reference to a const ByteType.
+   */
+  typedef const_or_non_const_ByteType& reference;
+#else // defined(GENERATING_DOCUMENTATION)
+  typedef typename detail::buffers_iterator_types<
+      BufferSequence, ByteType>::byte_type& reference;
+#endif // defined(GENERATING_DOCUMENTATION)
+
+  /// The iterator category.
+  typedef std::random_access_iterator_tag iterator_category;
+
+  /// Default constructor. Creates an iterator in an undefined state.
+  buffers_iterator()
+    : current_buffer_(),
+      current_buffer_position_(0),
+      begin_(),
+      current_(),
+      end_(),
+      position_(0)
+  {
+  }
+
+  /// Construct an iterator representing the beginning of the buffers' data.
+  static buffers_iterator begin(const BufferSequence& buffers)
+#if defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
+    __attribute__ ((__noinline__))
+#endif // defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
+  {
+    buffers_iterator new_iter;
+    new_iter.begin_ = boost::asio::buffer_sequence_begin(buffers);
+    new_iter.current_ = boost::asio::buffer_sequence_begin(buffers);
+    new_iter.end_ = boost::asio::buffer_sequence_end(buffers);
+    while (new_iter.current_ != new_iter.end_)
+    {
+      new_iter.current_buffer_ = *new_iter.current_;
+      if (new_iter.current_buffer_.size() > 0)
+        break;
+      ++new_iter.current_;
+    }
+    return new_iter;
+  }
+
+  /// Construct an iterator representing the end of the buffers' data.
+  static buffers_iterator end(const BufferSequence& buffers)
+#if defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
+    __attribute__ ((__noinline__))
+#endif // defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
+  {
+    buffers_iterator new_iter;
+    new_iter.begin_ = boost::asio::buffer_sequence_begin(buffers);
+    new_iter.current_ = boost::asio::buffer_sequence_begin(buffers);
+    new_iter.end_ = boost::asio::buffer_sequence_end(buffers);
+    while (new_iter.current_ != new_iter.end_)
+    {
+      buffer_type buffer = *new_iter.current_;
+      new_iter.position_ += buffer.size();
+      ++new_iter.current_;
+    }
+    return new_iter;
+  }
+
+  /// Dereference an iterator.
+  reference operator*() const
+  {
+    return dereference();
+  }
+
+  /// Dereference an iterator.
+  pointer operator->() const
+  {
+    return &dereference();
+  }
+
+  /// Access an individual element.
+  reference operator[](std::ptrdiff_t difference) const
+  {
+    buffers_iterator tmp(*this);
+    tmp.advance(difference);
+    return *tmp;
+  }
+
+  /// Increment operator (prefix).
+  buffers_iterator& operator++()
+  {
+    increment();
+    return *this;
+  }
+
+  /// Increment operator (postfix).
+  buffers_iterator operator++(int)
+  {
+    buffers_iterator tmp(*this);
+    ++*this;
+    return tmp;
+  }
+
+  /// Decrement operator (prefix).
+  buffers_iterator& operator--()
+  {
+    decrement();
+    return *this;
+  }
+
+  /// Decrement operator (postfix).
+  buffers_iterator operator--(int)
+  {
+    buffers_iterator tmp(*this);
+    --*this;
+    return tmp;
+  }
+
+  /// Addition operator.
+  buffers_iterator& operator+=(std::ptrdiff_t difference)
+  {
+    advance(difference);
+    return *this;
+  }
+
+  /// Subtraction operator.
+  buffers_iterator& operator-=(std::ptrdiff_t difference)
+  {
+    advance(-difference);
+    return *this;
+  }
+
+  /// Addition operator.
+  friend buffers_iterator operator+(const buffers_iterator& iter,
+      std::ptrdiff_t difference)
+  {
+    buffers_iterator tmp(iter);
+    tmp.advance(difference);
+    return tmp;
+  }
+
+  /// Addition operator.
+  friend buffers_iterator operator+(std::ptrdiff_t difference,
+      const buffers_iterator& iter)
+  {
+    buffers_iterator tmp(iter);
+    tmp.advance(difference);
+    return tmp;
+  }
+
+  /// Subtraction operator.
+  friend buffers_iterator operator-(const buffers_iterator& iter,
+      std::ptrdiff_t difference)
+  {
+    buffers_iterator tmp(iter);
+    tmp.advance(-difference);
+    return tmp;
+  }
+
+  /// Subtraction operator.
+  friend std::ptrdiff_t operator-(const buffers_iterator& a,
+      const buffers_iterator& b)
+  {
+    return b.distance_to(a);
+  }
+
+  /// Test two iterators for equality.
+  friend bool operator==(const buffers_iterator& a, const buffers_iterator& b)
+  {
+    return a.equal(b);
+  }
+
+  /// Test two iterators for inequality.
+  friend bool operator!=(const buffers_iterator& a, const buffers_iterator& b)
+  {
+    return !a.equal(b);
+  }
+
+  /// Compare two iterators.
+  friend bool operator<(const buffers_iterator& a, const buffers_iterator& b)
+  {
+    return a.distance_to(b) > 0;
+  }
+
+  /// Compare two iterators.
+  friend bool operator<=(const buffers_iterator& a, const buffers_iterator& b)
+  {
+    return !(b < a);
+  }
+
+  /// Compare two iterators.
+  friend bool operator>(const buffers_iterator& a, const buffers_iterator& b)
+  {
+    return b < a;
+  }
+
+  /// Compare two iterators.
+  friend bool operator>=(const buffers_iterator& a, const buffers_iterator& b)
+  {
+    return !(a < b);
+  }
+
+private:
+  // Dereference the iterator.
+  reference dereference() const
+  {
+    return static_cast<pointer>(
+        current_buffer_.data())[current_buffer_position_];
+  }
+
+  // Compare two iterators for equality.
+  bool equal(const buffers_iterator& other) const
+  {
+    return position_ == other.position_;
+  }
+
+  // Increment the iterator.
+  void increment()
+  {
+    BOOST_ASIO_ASSERT(current_ != end_ && "iterator out of bounds");
+    ++position_;
+
+    // Check if the increment can be satisfied by the current buffer.
+    ++current_buffer_position_;
+    if (current_buffer_position_ != current_buffer_.size())
+      return;
+
+    // Find the next non-empty buffer.
+    ++current_;
+    current_buffer_position_ = 0;
+    while (current_ != end_)
+    {
+      current_buffer_ = *current_;
+      if (current_buffer_.size() > 0)
+        return;
+      ++current_;
+    }
+  }
+
+  // Decrement the iterator.
+  void decrement()
+  {
+    BOOST_ASIO_ASSERT(position_ > 0 && "iterator out of bounds");
+    --position_;
+
+    // Check if the decrement can be satisfied by the current buffer.
+    if (current_buffer_position_ != 0)
+    {
+      --current_buffer_position_;
+      return;
+    }
+
+    // Find the previous non-empty buffer.
+    buffer_sequence_iterator_type iter = current_;
+    while (iter != begin_)
+    {
+      --iter;
+      buffer_type buffer = *iter;
+      std::size_t buffer_size = buffer.size();
+      if (buffer_size > 0)
+      {
+        current_ = iter;
+        current_buffer_ = buffer;
+        current_buffer_position_ = buffer_size - 1;
+        return;
+      }
+    }
+  }
+
+  // Advance the iterator by the specified distance.
+  void advance(std::ptrdiff_t n)
+  {
+    if (n > 0)
+    {
+      BOOST_ASIO_ASSERT(current_ != end_ && "iterator out of bounds");
+      for (;;)
+      {
+        std::ptrdiff_t current_buffer_balance
+          = current_buffer_.size() - current_buffer_position_;
+
+        // Check if the advance can be satisfied by the current buffer.
+        if (current_buffer_balance > n)
+        {
+          position_ += n;
+          current_buffer_position_ += n;
+          return;
+        }
+
+        // Update position.
+        n -= current_buffer_balance;
+        position_ += current_buffer_balance;
+
+        // Move to next buffer. If it is empty then it will be skipped on the
+        // next iteration of this loop.
+        if (++current_ == end_)
+        {
+          BOOST_ASIO_ASSERT(n == 0 && "iterator out of bounds");
+          current_buffer_ = buffer_type();
+          current_buffer_position_ = 0;
+          return;
+        }
+        current_buffer_ = *current_;
+        current_buffer_position_ = 0;
+      }
+    }
+    else if (n < 0)
+    {
+      std::size_t abs_n = -n;
+      BOOST_ASIO_ASSERT(position_ >= abs_n && "iterator out of bounds");
+      for (;;)
+      {
+        // Check if the advance can be satisfied by the current buffer.
+        if (current_buffer_position_ >= abs_n)
+        {
+          position_ -= abs_n;
+          current_buffer_position_ -= abs_n;
+          return;
+        }
+
+        // Update position.
+        abs_n -= current_buffer_position_;
+        position_ -= current_buffer_position_;
+
+        // Check if we've reached the beginning of the buffers.
+        if (current_ == begin_)
+        {
+          BOOST_ASIO_ASSERT(abs_n == 0 && "iterator out of bounds");
+          current_buffer_position_ = 0;
+          return;
+        }
+
+        // Find the previous non-empty buffer.
+        buffer_sequence_iterator_type iter = current_;
+        while (iter != begin_)
+        {
+          --iter;
+          buffer_type buffer = *iter;
+          std::size_t buffer_size = buffer.size();
+          if (buffer_size > 0)
+          {
+            current_ = iter;
+            current_buffer_ = buffer;
+            current_buffer_position_ = buffer_size;
+            break;
+          }
+        }
+      }
+    }
+  }
+
+  // Determine the distance between two iterators.
+  std::ptrdiff_t distance_to(const buffers_iterator& other) const
+  {
+    return other.position_ - position_;
+  }
+
+  buffer_type current_buffer_;
+  std::size_t current_buffer_position_;
+  buffer_sequence_iterator_type begin_;
+  buffer_sequence_iterator_type current_;
+  buffer_sequence_iterator_type end_;
+  std::size_t position_;
+};
+
+/// Construct an iterator representing the beginning of the buffers' data.
+template <typename BufferSequence>
+inline buffers_iterator<BufferSequence> buffers_begin(
+    const BufferSequence& buffers)
+{
+  return buffers_iterator<BufferSequence>::begin(buffers);
+}
+
+/// Construct an iterator representing the end of the buffers' data.
+template <typename BufferSequence>
+inline buffers_iterator<BufferSequence> buffers_end(
+    const BufferSequence& buffers)
+{
+  return buffers_iterator<BufferSequence>::end(buffers);
+}
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_BUFFERS_ITERATOR_HPP

boost/asio/co_spawn.hpp

@@ -0,0 +1,90 @@
+//
+// co_spawn.hpp
+// ~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_CO_SPAWN_HPP
+#define BOOST_ASIO_CO_SPAWN_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
+
+#include <boost/asio/awaitable.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/is_executor.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename T>
+struct awaitable_signature;
+
+template <typename T, typename Executor>
+struct awaitable_signature<awaitable<T, Executor>>
+{
+  typedef void type(std::exception_ptr, T);
+};
+
+template <typename Executor>
+struct awaitable_signature<awaitable<void, Executor>>
+{
+  typedef void type(std::exception_ptr);
+};
+
+} // namespace detail
+
+/// Spawn a new thread of execution.
+/**
+ * The entry point function object @c f must have the signature:
+ *
+ * @code awaitable<void, E> f(); @endcode
+ *
+ * where @c E is convertible from @c Executor.
+ */
+template <typename Executor, typename F, typename CompletionToken>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken,
+    typename detail::awaitable_signature<typename result_of<F()>::type>::type)
+co_spawn(const Executor& ex, F&& f, CompletionToken&& token,
+    typename enable_if<
+      is_executor<Executor>::value
+    >::type* = 0);
+
+/// Spawn a new thread of execution.
+/**
+ * The entry point function object @c f must have the signature:
+ *
+ * @code awaitable<void, E> f(); @endcode
+ *
+ * where @c E is convertible from @c ExecutionContext::executor_type.
+ */
+template <typename ExecutionContext, typename F, typename CompletionToken>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken,
+    typename detail::awaitable_signature<typename result_of<F()>::type>::type)
+co_spawn(ExecutionContext& ctx, F&& f, CompletionToken&& token,
+    typename enable_if<
+      is_convertible<ExecutionContext&, execution_context&>::value
+    >::type* = 0);
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/impl/co_spawn.hpp>
+
+#endif // defined(BOOST_ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
+
+#endif // BOOST_ASIO_CO_SPAWN_HPP

boost/asio/completion_condition.hpp

@@ -0,0 +1,220 @@
+//
+// completion_condition.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_COMPLETION_CONDITION_HPP
+#define BOOST_ASIO_COMPLETION_CONDITION_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+namespace detail {
+
+// The default maximum number of bytes to transfer in a single operation.
+enum default_max_transfer_size_t { default_max_transfer_size = 65536 };
+
+// Adapt result of old-style completion conditions (which had a bool result
+// where true indicated that the operation was complete).
+inline std::size_t adapt_completion_condition_result(bool result)
+{
+  return result ? 0 : default_max_transfer_size;
+}
+
+// Adapt result of current completion conditions (which have a size_t result
+// where 0 means the operation is complete, and otherwise the result is the
+// maximum number of bytes to transfer on the next underlying operation).
+inline std::size_t adapt_completion_condition_result(std::size_t result)
+{
+  return result;
+}
+
+class transfer_all_t
+{
+public:
+  typedef std::size_t result_type;
+
+  template <typename Error>
+  std::size_t operator()(const Error& err, std::size_t)
+  {
+    return !!err ? 0 : default_max_transfer_size;
+  }
+};
+
+class transfer_at_least_t
+{
+public:
+  typedef std::size_t result_type;
+
+  explicit transfer_at_least_t(std::size_t minimum)
+    : minimum_(minimum)
+  {
+  }
+
+  template <typename Error>
+  std::size_t operator()(const Error& err, std::size_t bytes_transferred)
+  {
+    return (!!err || bytes_transferred >= minimum_)
+      ? 0 : default_max_transfer_size;
+  }
+
+private:
+  std::size_t minimum_;
+};
+
+class transfer_exactly_t
+{
+public:
+  typedef std::size_t result_type;
+
+  explicit transfer_exactly_t(std::size_t size)
+    : size_(size)
+  {
+  }
+
+  template <typename Error>
+  std::size_t operator()(const Error& err, std::size_t bytes_transferred)
+  {
+    return (!!err || bytes_transferred >= size_) ? 0 :
+      (size_ - bytes_transferred < default_max_transfer_size
+        ? size_ - bytes_transferred : std::size_t(default_max_transfer_size));
+  }
+
+private:
+  std::size_t size_;
+};
+
+} // namespace detail
+
+/**
+ * @defgroup completion_condition Completion Condition Function Objects
+ *
+ * Function objects used for determining when a read or write operation should
+ * complete.
+ */
+/*@{*/
+
+/// Return a completion condition function object that indicates that a read or
+/// write operation should continue until all of the data has been transferred,
+/// or until an error occurs.
+/**
+ * This function is used to create an object, of unspecified type, that meets
+ * CompletionCondition requirements.
+ *
+ * @par Example
+ * Reading until a buffer is full:
+ * @code
+ * boost::array<char, 128> buf;
+ * boost::system::error_code ec;
+ * std::size_t n = boost::asio::read(
+ *     sock, boost::asio::buffer(buf),
+ *     boost::asio::transfer_all(), ec);
+ * if (ec)
+ * {
+ *   // An error occurred.
+ * }
+ * else
+ * {
+ *   // n == 128
+ * }
+ * @endcode
+ */
+#if defined(GENERATING_DOCUMENTATION)
+unspecified transfer_all();
+#else
+inline detail::transfer_all_t transfer_all()
+{
+  return detail::transfer_all_t();
+}
+#endif
+
+/// Return a completion condition function object that indicates that a read or
+/// write operation should continue until a minimum number of bytes has been
+/// transferred, or until an error occurs.
+/**
+ * This function is used to create an object, of unspecified type, that meets
+ * CompletionCondition requirements.
+ *
+ * @par Example
+ * Reading until a buffer is full or contains at least 64 bytes:
+ * @code
+ * boost::array<char, 128> buf;
+ * boost::system::error_code ec;
+ * std::size_t n = boost::asio::read(
+ *     sock, boost::asio::buffer(buf),
+ *     boost::asio::transfer_at_least(64), ec);
+ * if (ec)
+ * {
+ *   // An error occurred.
+ * }
+ * else
+ * {
+ *   // n >= 64 && n <= 128
+ * }
+ * @endcode
+ */
+#if defined(GENERATING_DOCUMENTATION)
+unspecified transfer_at_least(std::size_t minimum);
+#else
+inline detail::transfer_at_least_t transfer_at_least(std::size_t minimum)
+{
+  return detail::transfer_at_least_t(minimum);
+}
+#endif
+
+/// Return a completion condition function object that indicates that a read or
+/// write operation should continue until an exact number of bytes has been
+/// transferred, or until an error occurs.
+/**
+ * This function is used to create an object, of unspecified type, that meets
+ * CompletionCondition requirements.
+ *
+ * @par Example
+ * Reading until a buffer is full or contains exactly 64 bytes:
+ * @code
+ * boost::array<char, 128> buf;
+ * boost::system::error_code ec;
+ * std::size_t n = boost::asio::read(
+ *     sock, boost::asio::buffer(buf),
+ *     boost::asio::transfer_exactly(64), ec);
+ * if (ec)
+ * {
+ *   // An error occurred.
+ * }
+ * else
+ * {
+ *   // n == 64
+ * }
+ * @endcode
+ */
+#if defined(GENERATING_DOCUMENTATION)
+unspecified transfer_exactly(std::size_t size);
+#else
+inline detail::transfer_exactly_t transfer_exactly(std::size_t size)
+{
+  return detail::transfer_exactly_t(size);
+}
+#endif
+
+/*@}*/
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_COMPLETION_CONDITION_HPP

boost/asio/compose.hpp

@@ -0,0 +1,138 @@
+//
+// compose.hpp
+// ~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_COMPOSE_HPP
+#define BOOST_ASIO_COMPOSE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/async_result.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+#if defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES) \
+  || defined(GENERATING_DOCUMENTATION)
+
+/// Launch an asynchronous operation with a stateful implementation.
+/**
+ * The async_compose function simplifies the implementation of composed
+ * asynchronous operations automatically wrapping a stateful function object
+ * with a conforming intermediate completion handler.
+ *
+ * @param implementation A function object that contains the implementation of
+ * the composed asynchronous operation. The first argument to the function
+ * object is a non-const reference to the enclosing intermediate completion
+ * handler. The remaining arguments are any arguments that originate from the
+ * completion handlers of any asynchronous operations performed by the
+ * implementation.
+
+ * @param token The completion token.
+ *
+ * @param io_objects_or_executors Zero or more I/O objects or I/O executors for
+ * which outstanding work must be maintained.
+ *
+ * @par Example:
+ *
+ * @code struct async_echo_implementation
+ * {
+ *   tcp::socket& socket_;
+ *   boost::asio::mutable_buffer buffer_;
+ *   enum { starting, reading, writing } state_;
+ *
+ *   template <typename Self>
+ *   void operator()(Self& self,
+ *       boost::system::error_code error = {},
+ *       std::size_t n = 0)
+ *   {
+ *     switch (state_)
+ *     {
+ *     case starting:
+ *       state_ = reading;
+ *       socket_.async_read_some(
+ *           buffer_, std::move(self));
+ *       break;
+ *     case reading:
+ *       if (error)
+ *       {
+ *         self.complete(error, 0);
+ *       }
+ *       else
+ *       {
+ *         state_ = writing;
+ *         boost::asio::async_write(socket_, buffer_,
+ *             boost::asio::transfer_exactly(n),
+ *             std::move(self));
+ *       }
+ *       break;
+ *     case writing:
+ *       self.complete(error, n);
+ *       break;
+ *     }
+ *   }
+ * };
+ *
+ * template <typename CompletionToken>
+ * auto async_echo(tcp::socket& socket,
+ *     boost::asio::mutable_buffer buffer,
+ *     CompletionToken&& token) ->
+ *   typename boost::asio::async_result<
+ *     typename std::decay<CompletionToken>::type,
+ *       void(boost::system::error_code, std::size_t)>::return_type
+ * {
+ *   return boost::asio::async_compose<CompletionToken,
+ *     void(boost::system::error_code, std::size_t)>(
+ *       async_echo_implementation{socket, buffer,
+ *         async_echo_implementation::starting},
+ *       token, socket);
+ * } @endcode
+ */
+template <typename CompletionToken, typename Signature,
+    typename Implementation, typename... IoObjectsOrExecutors>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)
+async_compose(BOOST_ASIO_MOVE_ARG(Implementation) implementation,
+    BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token,
+    BOOST_ASIO_MOVE_ARG(IoObjectsOrExecutors)... io_objects_or_executors);
+
+#else // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+      //   || defined(GENERATING_DOCUMENTATION)
+
+template <typename CompletionToken, typename Signature, typename Implementation>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)
+async_compose(BOOST_ASIO_MOVE_ARG(Implementation) implementation,
+    BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token);
+
+#define BOOST_ASIO_PRIVATE_ASYNC_COMPOSE_DEF(n) \
+  template <typename CompletionToken, typename Signature, \
+      typename Implementation, BOOST_ASIO_VARIADIC_TPARAMS(n)> \
+  BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature) \
+  async_compose(BOOST_ASIO_MOVE_ARG(Implementation) implementation, \
+      BOOST_ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token, \
+      BOOST_ASIO_VARIADIC_MOVE_PARAMS(n));
+  /**/
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_ASYNC_COMPOSE_DEF)
+#undef BOOST_ASIO_PRIVATE_ASYNC_COMPOSE_DEF
+
+#endif // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+       //   || defined(GENERATING_DOCUMENTATION)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/impl/compose.hpp>
+
+#endif // BOOST_ASIO_COMPOSE_HPP

boost/asio/coroutine.hpp

@@ -0,0 +1,330 @@
+//
+// coroutine.hpp
+// ~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_COROUTINE_HPP
+#define BOOST_ASIO_COROUTINE_HPP
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class coroutine_ref;
+
+} // namespace detail
+
+/// Provides support for implementing stackless coroutines.
+/**
+ * The @c coroutine class may be used to implement stackless coroutines. The
+ * class itself is used to store the current state of the coroutine.
+ *
+ * Coroutines are copy-constructible and assignable, and the space overhead is
+ * a single int. They can be used as a base class:
+ *
+ * @code class session : coroutine
+ * {
+ *   ...
+ * }; @endcode
+ *
+ * or as a data member:
+ *
+ * @code class session
+ * {
+ *   ...
+ *   coroutine coro_;
+ * }; @endcode
+ *
+ * or even bound in as a function argument using lambdas or @c bind(). The
+ * important thing is that as the application maintains a copy of the object
+ * for as long as the coroutine must be kept alive.
+ *
+ * @par Pseudo-keywords
+ *
+ * A coroutine is used in conjunction with certain "pseudo-keywords", which
+ * are implemented as macros. These macros are defined by a header file:
+ *
+ * @code #include <boost/asio/yield.hpp>@endcode
+ *
+ * and may conversely be undefined as follows:
+ *
+ * @code #include <boost/asio/unyield.hpp>@endcode
+ *
+ * <b>reenter</b>
+ *
+ * The @c reenter macro is used to define the body of a coroutine. It takes a
+ * single argument: a pointer or reference to a coroutine object. For example,
+ * if the base class is a coroutine object you may write:
+ *
+ * @code reenter (this)
+ * {
+ *   ... coroutine body ...
+ * } @endcode
+ *
+ * and if a data member or other variable you can write:
+ *
+ * @code reenter (coro_)
+ * {
+ *   ... coroutine body ...
+ * } @endcode
+ *
+ * When @c reenter is executed at runtime, control jumps to the location of the
+ * last @c yield or @c fork.
+ *
+ * The coroutine body may also be a single statement, such as:
+ *
+ * @code reenter (this) for (;;)
+ * {
+ *   ...
+ * } @endcode
+ *
+ * @b Limitation: The @c reenter macro is implemented using a switch. This
+ * means that you must take care when using local variables within the
+ * coroutine body. The local variable is not allowed in a position where
+ * reentering the coroutine could bypass the variable definition.
+ *
+ * <b>yield <em>statement</em></b>
+ *
+ * This form of the @c yield keyword is often used with asynchronous operations:
+ *
+ * @code yield socket_->async_read_some(buffer(*buffer_), *this); @endcode
+ *
+ * This divides into four logical steps:
+ *
+ * @li @c yield saves the current state of the coroutine.
+ * @li The statement initiates the asynchronous operation.
+ * @li The resume point is defined immediately following the statement.
+ * @li Control is transferred to the end of the coroutine body.
+ *
+ * When the asynchronous operation completes, the function object is invoked
+ * and @c reenter causes control to transfer to the resume point. It is
+ * important to remember to carry the coroutine state forward with the
+ * asynchronous operation. In the above snippet, the current class is a
+ * function object object with a coroutine object as base class or data member.
+ *
+ * The statement may also be a compound statement, and this permits us to
+ * define local variables with limited scope:
+ *
+ * @code yield
+ * {
+ *   mutable_buffers_1 b = buffer(*buffer_);
+ *   socket_->async_read_some(b, *this);
+ * } @endcode
+ *
+ * <b>yield return <em>expression</em> ;</b>
+ *
+ * This form of @c yield is often used in generators or coroutine-based parsers.
+ * For example, the function object:
+ *
+ * @code struct interleave : coroutine
+ * {
+ *   istream& is1;
+ *   istream& is2;
+ *   char operator()(char c)
+ *   {
+ *     reenter (this) for (;;)
+ *     {
+ *       yield return is1.get();
+ *       yield return is2.get();
+ *     }
+ *   }
+ * }; @endcode
+ *
+ * defines a trivial coroutine that interleaves the characters from two input
+ * streams.
+ *
+ * This type of @c yield divides into three logical steps:
+ *
+ * @li @c yield saves the current state of the coroutine.
+ * @li The resume point is defined immediately following the semicolon.
+ * @li The value of the expression is returned from the function.
+ *
+ * <b>yield ;</b>
+ *
+ * This form of @c yield is equivalent to the following steps:
+ *
+ * @li @c yield saves the current state of the coroutine.
+ * @li The resume point is defined immediately following the semicolon.
+ * @li Control is transferred to the end of the coroutine body.
+ *
+ * This form might be applied when coroutines are used for cooperative
+ * threading and scheduling is explicitly managed. For example:
+ *
+ * @code struct task : coroutine
+ * {
+ *   ...
+ *   void operator()()
+ *   {
+ *     reenter (this)
+ *     {
+ *       while (... not finished ...)
+ *       {
+ *         ... do something ...
+ *         yield;
+ *         ... do some more ...
+ *         yield;
+ *       }
+ *     }
+ *   }
+ *   ...
+ * };
+ * ...
+ * task t1, t2;
+ * for (;;)
+ * {
+ *   t1();
+ *   t2();
+ * } @endcode
+ *
+ * <b>yield break ;</b>
+ *
+ * The final form of @c yield is used to explicitly terminate the coroutine.
+ * This form is comprised of two steps:
+ *
+ * @li @c yield sets the coroutine state to indicate termination.
+ * @li Control is transferred to the end of the coroutine body.
+ *
+ * Once terminated, calls to is_complete() return true and the coroutine cannot
+ * be reentered.
+ *
+ * Note that a coroutine may also be implicitly terminated if the coroutine
+ * body is exited without a yield, e.g. by return, throw or by running to the
+ * end of the body.
+ *
+ * <b>fork <em>statement</em></b>
+ *
+ * The @c fork pseudo-keyword is used when "forking" a coroutine, i.e. splitting
+ * it into two (or more) copies. One use of @c fork is in a server, where a new
+ * coroutine is created to handle each client connection:
+ * 
+ * @code reenter (this)
+ * {
+ *   do
+ *   {
+ *     socket_.reset(new tcp::socket(my_context_));
+ *     yield acceptor->async_accept(*socket_, *this);
+ *     fork server(*this)();
+ *   } while (is_parent());
+ *   ... client-specific handling follows ...
+ * } @endcode
+ * 
+ * The logical steps involved in a @c fork are:
+ * 
+ * @li @c fork saves the current state of the coroutine.
+ * @li The statement creates a copy of the coroutine and either executes it
+ *     immediately or schedules it for later execution.
+ * @li The resume point is defined immediately following the semicolon.
+ * @li For the "parent", control immediately continues from the next line.
+ *
+ * The functions is_parent() and is_child() can be used to differentiate
+ * between parent and child. You would use these functions to alter subsequent
+ * control flow.
+ *
+ * Note that @c fork doesn't do the actual forking by itself. It is the
+ * application's responsibility to create a clone of the coroutine and call it.
+ * The clone can be called immediately, as above, or scheduled for delayed
+ * execution using something like boost::asio::post().
+ *
+ * @par Alternate macro names
+ *
+ * If preferred, an application can use macro names that follow a more typical
+ * naming convention, rather than the pseudo-keywords. These are:
+ *
+ * @li @c BOOST_ASIO_CORO_REENTER instead of @c reenter
+ * @li @c BOOST_ASIO_CORO_YIELD instead of @c yield
+ * @li @c BOOST_ASIO_CORO_FORK instead of @c fork
+ */
+class coroutine
+{
+public:
+  /// Constructs a coroutine in its initial state.
+  coroutine() : value_(0) {}
+
+  /// Returns true if the coroutine is the child of a fork.
+  bool is_child() const { return value_ < 0; }
+
+  /// Returns true if the coroutine is the parent of a fork.
+  bool is_parent() const { return !is_child(); }
+
+  /// Returns true if the coroutine has reached its terminal state.
+  bool is_complete() const { return value_ == -1; }
+
+private:
+  friend class detail::coroutine_ref;
+  int value_;
+};
+
+
+namespace detail {
+
+class coroutine_ref
+{
+public:
+  coroutine_ref(coroutine& c) : value_(c.value_), modified_(false) {}
+  coroutine_ref(coroutine* c) : value_(c->value_), modified_(false) {}
+  ~coroutine_ref() { if (!modified_) value_ = -1; }
+  operator int() const { return value_; }
+  int& operator=(int v) { modified_ = true; return value_ = v; }
+private:
+  void operator=(const coroutine_ref&);
+  int& value_;
+  bool modified_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#define BOOST_ASIO_CORO_REENTER(c) \
+  switch (::boost::asio::detail::coroutine_ref _coro_value = c) \
+    case -1: if (_coro_value) \
+    { \
+      goto terminate_coroutine; \
+      terminate_coroutine: \
+      _coro_value = -1; \
+      goto bail_out_of_coroutine; \
+      bail_out_of_coroutine: \
+      break; \
+    } \
+    else /* fall-through */ case 0:
+
+#define BOOST_ASIO_CORO_YIELD_IMPL(n) \
+  for (_coro_value = (n);;) \
+    if (_coro_value == 0) \
+    { \
+      case (n): ; \
+      break; \
+    } \
+    else \
+      switch (_coro_value ? 0 : 1) \
+        for (;;) \
+          /* fall-through */ case -1: if (_coro_value) \
+            goto terminate_coroutine; \
+          else for (;;) \
+            /* fall-through */ case 1: if (_coro_value) \
+              goto bail_out_of_coroutine; \
+            else /* fall-through */ case 0:
+
+#define BOOST_ASIO_CORO_FORK_IMPL(n) \
+  for (_coro_value = -(n);; _coro_value = (n)) \
+    if (_coro_value == (n)) \
+    { \
+      case -(n): ; \
+      break; \
+    } \
+    else
+
+#if defined(_MSC_VER)
+# define BOOST_ASIO_CORO_YIELD BOOST_ASIO_CORO_YIELD_IMPL(__COUNTER__ + 1)
+# define BOOST_ASIO_CORO_FORK BOOST_ASIO_CORO_FORK_IMPL(__COUNTER__ + 1)
+#else // defined(_MSC_VER)
+# define BOOST_ASIO_CORO_YIELD BOOST_ASIO_CORO_YIELD_IMPL(__LINE__)
+# define BOOST_ASIO_CORO_FORK BOOST_ASIO_CORO_FORK_IMPL(__LINE__)
+#endif // defined(_MSC_VER)
+
+#endif // BOOST_ASIO_COROUTINE_HPP

boost/asio/deadline_timer.hpp

@@ -0,0 +1,40 @@
+//
+// deadline_timer.hpp
+// ~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DEADLINE_TIMER_HPP
+#define BOOST_ASIO_DEADLINE_TIMER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_BOOST_DATE_TIME) \
+  || defined(GENERATING_DOCUMENTATION)
+
+#include <boost/asio/detail/socket_types.hpp> // Must come before posix_time.
+#include <boost/asio/basic_deadline_timer.hpp>
+
+#include <boost/date_time/posix_time/posix_time_types.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Typedef for the typical usage of timer. Uses a UTC clock.
+typedef basic_deadline_timer<boost::posix_time::ptime> deadline_timer;
+
+} // namespace asio
+} // namespace boost
+
+#endif // defined(BOOST_ASIO_HAS_BOOST_DATE_TIME)
+       // || defined(GENERATING_DOCUMENTATION)
+
+#endif // BOOST_ASIO_DEADLINE_TIMER_HPP

boost/asio/defer.hpp

@@ -0,0 +1,119 @@
+//
+// defer.hpp
+// ~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DEFER_HPP
+#define BOOST_ASIO_DEFER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/is_executor.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Submits a completion token or function object for execution.
+/**
+ * This function submits an object for execution using the object's associated
+ * executor. The function object is queued for execution, and is never called
+ * from the current thread prior to returning from <tt>defer()</tt>.
+ *
+ * The use of @c defer(), rather than @ref post(), indicates the caller's
+ * preference that the executor defer the queueing of the function object. This
+ * may allow the executor to optimise queueing for cases when the function
+ * object represents a continuation of the current call context.
+ *
+ * This function has the following effects:
+ *
+ * @li Constructs a function object handler of type @c Handler, initialized
+ * with <tt>handler(forward<CompletionToken>(token))</tt>.
+ *
+ * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
+ * initializing the object as <tt>result(handler)</tt>.
+ *
+ * @li Obtains the handler's associated executor object @c ex by performing
+ * <tt>get_associated_executor(handler)</tt>.
+ *
+ * @li Obtains the handler's associated allocator object @c alloc by performing
+ * <tt>get_associated_allocator(handler)</tt>.
+ *
+ * @li Performs <tt>ex.defer(std::move(handler), alloc)</tt>.
+ *
+ * @li Returns <tt>result.get()</tt>.
+ */
+template <typename CompletionToken>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, void()) defer(
+    BOOST_ASIO_MOVE_ARG(CompletionToken) token);
+
+/// Submits a completion token or function object for execution.
+/**
+ * This function submits an object for execution using the specified executor.
+ * The function object is queued for execution, and is never called from the
+ * current thread prior to returning from <tt>defer()</tt>.
+ *
+ * The use of @c defer(), rather than @ref post(), indicates the caller's
+ * preference that the executor defer the queueing of the function object. This
+ * may allow the executor to optimise queueing for cases when the function
+ * object represents a continuation of the current call context.
+ *
+ * This function has the following effects:
+ *
+ * @li Constructs a function object handler of type @c Handler, initialized
+ * with <tt>handler(forward<CompletionToken>(token))</tt>.
+ *
+ * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
+ * initializing the object as <tt>result(handler)</tt>.
+ *
+ * @li Obtains the handler's associated executor object @c ex1 by performing
+ * <tt>get_associated_executor(handler)</tt>.
+ *
+ * @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
+ *
+ * @li Obtains the handler's associated allocator object @c alloc by performing
+ * <tt>get_associated_allocator(handler)</tt>.
+ *
+ * @li Constructs a function object @c f with a function call operator that
+ * performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
+ * <tt>w.reset()</tt>.
+ *
+ * @li Performs <tt>Executor(ex).defer(std::move(f), alloc)</tt>.
+ *
+ * @li Returns <tt>result.get()</tt>.
+ */
+template <typename Executor, typename CompletionToken>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, void()) defer(
+    const Executor& ex, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
+    typename enable_if<is_executor<Executor>::value>::type* = 0);
+
+/// Submits a completion token or function object for execution.
+/**
+ * @returns <tt>defer(ctx.get_executor(), forward<CompletionToken>(token))</tt>.
+ */
+template <typename ExecutionContext, typename CompletionToken>
+BOOST_ASIO_INITFN_RESULT_TYPE(CompletionToken, void()) defer(
+    ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
+    typename enable_if<is_convertible<
+      ExecutionContext&, execution_context&>::value>::type* = 0);
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/impl/defer.hpp>
+
+#endif // BOOST_ASIO_DEFER_HPP

boost/asio/detached.hpp

@@ -0,0 +1,64 @@
+//
+// detached.hpp
+// ~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETACHED_HPP
+#define BOOST_ASIO_DETACHED_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <memory>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+/// Class used to specify that an asynchronous operation is detached.
+/**
+
+ * The detached_t class is used to indicate that an asynchronous operation is
+ * detached. That is, there is no completion handler waiting for the
+ * operation's result. A detached_t object may be passed as a handler to an
+ * asynchronous operation, typically using the special value
+ * @c boost::asio::detached. For example:
+
+ * @code my_socket.async_send(my_buffer, boost::asio::detached);
+ * @endcode
+ */
+class detached_t
+{
+public:
+  /// Constructor. 
+  BOOST_ASIO_CONSTEXPR detached_t()
+  {
+  }
+};
+
+/// A special value, similar to std::nothrow.
+/**
+ * See the documentation for boost::asio::detached_t for a usage example.
+ */
+#if defined(BOOST_ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
+constexpr detached_t detached;
+#elif defined(BOOST_ASIO_MSVC)
+__declspec(selectany) detached_t detached;
+#endif
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/impl/detached.hpp>
+
+#endif // BOOST_ASIO_DETACHED_HPP

boost/asio/detail/array.hpp

@@ -0,0 +1,40 @@
+//
+// detail/array.hpp
+// ~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_ARRAY_HPP
+#define BOOST_ASIO_DETAIL_ARRAY_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_STD_ARRAY)
+# include <array>
+#else // defined(BOOST_ASIO_HAS_STD_ARRAY)
+# include <boost/array.hpp>
+#endif // defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+#if defined(BOOST_ASIO_HAS_STD_ARRAY)
+using std::array;
+#else // defined(BOOST_ASIO_HAS_STD_ARRAY)
+using boost::array;
+#endif // defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_ARRAY_HPP

boost/asio/detail/array_fwd.hpp

@@ -0,0 +1,34 @@
+//
+// detail/array_fwd.hpp
+// ~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_ARRAY_FWD_HPP
+#define BOOST_ASIO_DETAIL_ARRAY_FWD_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+namespace boost {
+
+template<class T, std::size_t N>
+class array;
+
+} // namespace boost
+
+// Standard library components can't be forward declared, so we'll have to
+// include the array header. Fortunately, it's fairly lightweight and doesn't
+// add significantly to the compile time.
+#if defined(BOOST_ASIO_HAS_STD_ARRAY)
+# include <array>
+#endif // defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+#endif // BOOST_ASIO_DETAIL_ARRAY_FWD_HPP

boost/asio/detail/assert.hpp

@@ -0,0 +1,32 @@
+//
+// detail/assert.hpp
+// ~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_ASSERT_HPP
+#define BOOST_ASIO_DETAIL_ASSERT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_BOOST_ASSERT)
+# include <boost/assert.hpp>
+#else // defined(BOOST_ASIO_HAS_BOOST_ASSERT)
+# include <cassert>
+#endif // defined(BOOST_ASIO_HAS_BOOST_ASSERT)
+
+#if defined(BOOST_ASIO_HAS_BOOST_ASSERT)
+# define BOOST_ASIO_ASSERT(expr) BOOST_ASSERT(expr)
+#else // defined(BOOST_ASIO_HAS_BOOST_ASSERT)
+# define BOOST_ASIO_ASSERT(expr) assert(expr)
+#endif // defined(BOOST_ASIO_HAS_BOOST_ASSERT)
+
+#endif // BOOST_ASIO_DETAIL_ASSERT_HPP

boost/asio/detail/atomic_count.hpp

@@ -0,0 +1,47 @@
+//
+// detail/atomic_count.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_ATOMIC_COUNT_HPP
+#define BOOST_ASIO_DETAIL_ATOMIC_COUNT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_HAS_THREADS)
+// Nothing to include.
+#elif defined(BOOST_ASIO_HAS_STD_ATOMIC)
+# include <atomic>
+#else // defined(BOOST_ASIO_HAS_STD_ATOMIC)
+# include <boost/detail/atomic_count.hpp>
+#endif // defined(BOOST_ASIO_HAS_STD_ATOMIC)
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+#if !defined(BOOST_ASIO_HAS_THREADS)
+typedef long atomic_count;
+inline void increment(atomic_count& a, long b) { a += b; }
+#elif defined(BOOST_ASIO_HAS_STD_ATOMIC)
+typedef std::atomic<long> atomic_count;
+inline void increment(atomic_count& a, long b) { a += b; }
+#else // defined(BOOST_ASIO_HAS_STD_ATOMIC)
+typedef boost::detail::atomic_count atomic_count;
+inline void increment(atomic_count& a, long b) { while (b > 0) ++a, --b; }
+#endif // defined(BOOST_ASIO_HAS_STD_ATOMIC)
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_ATOMIC_COUNT_HPP

boost/asio/detail/base_from_completion_cond.hpp

@@ -0,0 +1,71 @@
+//
+// detail/base_from_completion_cond.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_BASE_FROM_COMPLETION_COND_HPP
+#define BOOST_ASIO_DETAIL_BASE_FROM_COMPLETION_COND_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/completion_condition.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename CompletionCondition>
+class base_from_completion_cond
+{
+protected:
+  explicit base_from_completion_cond(CompletionCondition& completion_condition)
+    : completion_condition_(
+        BOOST_ASIO_MOVE_CAST(CompletionCondition)(completion_condition))
+  {
+  }
+
+  std::size_t check_for_completion(
+      const boost::system::error_code& ec,
+      std::size_t total_transferred)
+  {
+    return detail::adapt_completion_condition_result(
+        completion_condition_(ec, total_transferred));
+  }
+
+private:
+  CompletionCondition completion_condition_;
+};
+
+template <>
+class base_from_completion_cond<transfer_all_t>
+{
+protected:
+  explicit base_from_completion_cond(transfer_all_t)
+  {
+  }
+
+  static std::size_t check_for_completion(
+      const boost::system::error_code& ec,
+      std::size_t total_transferred)
+  {
+    return transfer_all_t()(ec, total_transferred);
+  }
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_BASE_FROM_COMPLETION_COND_HPP

boost/asio/detail/bind_handler.hpp

@@ -0,0 +1,818 @@
+//
+// detail/bind_handler.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_BIND_HANDLER_HPP
+#define BOOST_ASIO_DETAIL_BIND_HANDLER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/associated_allocator.hpp>
+#include <boost/asio/associated_executor.hpp>
+#include <boost/asio/detail/handler_alloc_helpers.hpp>
+#include <boost/asio/detail/handler_cont_helpers.hpp>
+#include <boost/asio/detail/handler_invoke_helpers.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename Handler, typename Arg1>
+class binder1
+{
+public:
+  template <typename T>
+  binder1(int, BOOST_ASIO_MOVE_ARG(T) handler, const Arg1& arg1)
+    : handler_(BOOST_ASIO_MOVE_CAST(T)(handler)),
+      arg1_(arg1)
+  {
+  }
+
+  binder1(Handler& handler, const Arg1& arg1)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      arg1_(arg1)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+  binder1(const binder1& other)
+    : handler_(other.handler_),
+      arg1_(other.arg1_)
+  {
+  }
+
+  binder1(binder1&& other)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(other.handler_)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(other.arg1_))
+  {
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+  void operator()()
+  {
+    handler_(static_cast<const Arg1&>(arg1_));
+  }
+
+  void operator()() const
+  {
+    handler_(arg1_);
+  }
+
+//private:
+  Handler handler_;
+  Arg1 arg1_;
+};
+
+template <typename Handler, typename Arg1>
+inline void* asio_handler_allocate(std::size_t size,
+    binder1<Handler, Arg1>* this_handler)
+{
+  return boost_asio_handler_alloc_helpers::allocate(
+      size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1>
+inline void asio_handler_deallocate(void* pointer, std::size_t size,
+    binder1<Handler, Arg1>* this_handler)
+{
+  boost_asio_handler_alloc_helpers::deallocate(
+      pointer, size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1>
+inline bool asio_handler_is_continuation(
+    binder1<Handler, Arg1>* this_handler)
+{
+  return boost_asio_handler_cont_helpers::is_continuation(
+      this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1>
+inline void asio_handler_invoke(Function& function,
+    binder1<Handler, Arg1>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1>
+inline void asio_handler_invoke(const Function& function,
+    binder1<Handler, Arg1>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1>
+inline binder1<typename decay<Handler>::type, Arg1> bind_handler(
+    BOOST_ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1)
+{
+  return binder1<typename decay<Handler>::type, Arg1>(0,
+      BOOST_ASIO_MOVE_CAST(Handler)(handler), arg1);
+}
+
+template <typename Handler, typename Arg1, typename Arg2>
+class binder2
+{
+public:
+  template <typename T>
+  binder2(int, BOOST_ASIO_MOVE_ARG(T) handler,
+      const Arg1& arg1, const Arg2& arg2)
+    : handler_(BOOST_ASIO_MOVE_CAST(T)(handler)),
+      arg1_(arg1),
+      arg2_(arg2)
+  {
+  }
+
+  binder2(Handler& handler, const Arg1& arg1, const Arg2& arg2)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      arg1_(arg1),
+      arg2_(arg2)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+  binder2(const binder2& other)
+    : handler_(other.handler_),
+      arg1_(other.arg1_),
+      arg2_(other.arg2_)
+  {
+  }
+
+  binder2(binder2&& other)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(other.handler_)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(other.arg1_)),
+      arg2_(BOOST_ASIO_MOVE_CAST(Arg2)(other.arg2_))
+  {
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+  void operator()()
+  {
+    handler_(static_cast<const Arg1&>(arg1_),
+        static_cast<const Arg2&>(arg2_));
+  }
+
+  void operator()() const
+  {
+    handler_(arg1_, arg2_);
+  }
+
+//private:
+  Handler handler_;
+  Arg1 arg1_;
+  Arg2 arg2_;
+};
+
+template <typename Handler, typename Arg1, typename Arg2>
+inline void* asio_handler_allocate(std::size_t size,
+    binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  return boost_asio_handler_alloc_helpers::allocate(
+      size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2>
+inline void asio_handler_deallocate(void* pointer, std::size_t size,
+    binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  boost_asio_handler_alloc_helpers::deallocate(
+      pointer, size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2>
+inline bool asio_handler_is_continuation(
+    binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  return boost_asio_handler_cont_helpers::is_continuation(
+      this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1, typename Arg2>
+inline void asio_handler_invoke(Function& function,
+    binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1, typename Arg2>
+inline void asio_handler_invoke(const Function& function,
+    binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2>
+inline binder2<typename decay<Handler>::type, Arg1, Arg2> bind_handler(
+    BOOST_ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1, const Arg2& arg2)
+{
+  return binder2<typename decay<Handler>::type, Arg1, Arg2>(0,
+      BOOST_ASIO_MOVE_CAST(Handler)(handler), arg1, arg2);
+}
+
+template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
+class binder3
+{
+public:
+  template <typename T>
+  binder3(int, BOOST_ASIO_MOVE_ARG(T) handler, const Arg1& arg1,
+      const Arg2& arg2, const Arg3& arg3)
+    : handler_(BOOST_ASIO_MOVE_CAST(T)(handler)),
+      arg1_(arg1),
+      arg2_(arg2),
+      arg3_(arg3)
+  {
+  }
+
+  binder3(Handler& handler, const Arg1& arg1,
+      const Arg2& arg2, const Arg3& arg3)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      arg1_(arg1),
+      arg2_(arg2),
+      arg3_(arg3)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+  binder3(const binder3& other)
+    : handler_(other.handler_),
+      arg1_(other.arg1_),
+      arg2_(other.arg2_),
+      arg3_(other.arg3_)
+  {
+  }
+
+  binder3(binder3&& other)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(other.handler_)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(other.arg1_)),
+      arg2_(BOOST_ASIO_MOVE_CAST(Arg2)(other.arg2_)),
+      arg3_(BOOST_ASIO_MOVE_CAST(Arg3)(other.arg3_))
+  {
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+  void operator()()
+  {
+    handler_(static_cast<const Arg1&>(arg1_),
+        static_cast<const Arg2&>(arg2_), static_cast<const Arg3&>(arg3_));
+  }
+
+  void operator()() const
+  {
+    handler_(arg1_, arg2_, arg3_);
+  }
+
+//private:
+  Handler handler_;
+  Arg1 arg1_;
+  Arg2 arg2_;
+  Arg3 arg3_;
+};
+
+template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
+inline void* asio_handler_allocate(std::size_t size,
+    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
+{
+  return boost_asio_handler_alloc_helpers::allocate(
+      size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
+inline void asio_handler_deallocate(void* pointer, std::size_t size,
+    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
+{
+  boost_asio_handler_alloc_helpers::deallocate(
+      pointer, size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
+inline bool asio_handler_is_continuation(
+    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
+{
+  return boost_asio_handler_cont_helpers::is_continuation(
+      this_handler->handler_);
+}
+
+template <typename Function, typename Handler,
+    typename Arg1, typename Arg2, typename Arg3>
+inline void asio_handler_invoke(Function& function,
+    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Function, typename Handler,
+    typename Arg1, typename Arg2, typename Arg3>
+inline void asio_handler_invoke(const Function& function,
+    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
+inline binder3<typename decay<Handler>::type, Arg1, Arg2, Arg3> bind_handler(
+    BOOST_ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1, const Arg2& arg2,
+    const Arg3& arg3)
+{
+  return binder3<typename decay<Handler>::type, Arg1, Arg2, Arg3>(0,
+      BOOST_ASIO_MOVE_CAST(Handler)(handler), arg1, arg2, arg3);
+}
+
+template <typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4>
+class binder4
+{
+public:
+  template <typename T>
+  binder4(int, BOOST_ASIO_MOVE_ARG(T) handler, const Arg1& arg1,
+      const Arg2& arg2, const Arg3& arg3, const Arg4& arg4)
+    : handler_(BOOST_ASIO_MOVE_CAST(T)(handler)),
+      arg1_(arg1),
+      arg2_(arg2),
+      arg3_(arg3),
+      arg4_(arg4)
+  {
+  }
+
+  binder4(Handler& handler, const Arg1& arg1,
+      const Arg2& arg2, const Arg3& arg3, const Arg4& arg4)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      arg1_(arg1),
+      arg2_(arg2),
+      arg3_(arg3),
+      arg4_(arg4)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+  binder4(const binder4& other)
+    : handler_(other.handler_),
+      arg1_(other.arg1_),
+      arg2_(other.arg2_),
+      arg3_(other.arg3_),
+      arg4_(other.arg4_)
+  {
+  }
+
+  binder4(binder4&& other)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(other.handler_)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(other.arg1_)),
+      arg2_(BOOST_ASIO_MOVE_CAST(Arg2)(other.arg2_)),
+      arg3_(BOOST_ASIO_MOVE_CAST(Arg3)(other.arg3_)),
+      arg4_(BOOST_ASIO_MOVE_CAST(Arg4)(other.arg4_))
+  {
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+  void operator()()
+  {
+    handler_(static_cast<const Arg1&>(arg1_),
+        static_cast<const Arg2&>(arg2_), static_cast<const Arg3&>(arg3_),
+        static_cast<const Arg4&>(arg4_));
+  }
+
+  void operator()() const
+  {
+    handler_(arg1_, arg2_, arg3_, arg4_);
+  }
+
+//private:
+  Handler handler_;
+  Arg1 arg1_;
+  Arg2 arg2_;
+  Arg3 arg3_;
+  Arg4 arg4_;
+};
+
+template <typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4>
+inline void* asio_handler_allocate(std::size_t size,
+    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
+{
+  return boost_asio_handler_alloc_helpers::allocate(
+      size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4>
+inline void asio_handler_deallocate(void* pointer, std::size_t size,
+    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
+{
+  boost_asio_handler_alloc_helpers::deallocate(
+      pointer, size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4>
+inline bool asio_handler_is_continuation(
+    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
+{
+  return boost_asio_handler_cont_helpers::is_continuation(
+      this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4>
+inline void asio_handler_invoke(Function& function,
+    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4>
+inline void asio_handler_invoke(const Function& function,
+    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4>
+inline binder4<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4>
+bind_handler(BOOST_ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1,
+    const Arg2& arg2, const Arg3& arg3, const Arg4& arg4)
+{
+  return binder4<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4>(0,
+      BOOST_ASIO_MOVE_CAST(Handler)(handler), arg1, arg2, arg3, arg4);
+}
+
+template <typename Handler, typename Arg1, typename Arg2,
+    typename Arg3, typename Arg4, typename Arg5>
+class binder5
+{
+public:
+  template <typename T>
+  binder5(int, BOOST_ASIO_MOVE_ARG(T) handler, const Arg1& arg1,
+      const Arg2& arg2, const Arg3& arg3, const Arg4& arg4, const Arg5& arg5)
+    : handler_(BOOST_ASIO_MOVE_CAST(T)(handler)),
+      arg1_(arg1),
+      arg2_(arg2),
+      arg3_(arg3),
+      arg4_(arg4),
+      arg5_(arg5)
+  {
+  }
+
+  binder5(Handler& handler, const Arg1& arg1, const Arg2& arg2,
+      const Arg3& arg3, const Arg4& arg4, const Arg5& arg5)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      arg1_(arg1),
+      arg2_(arg2),
+      arg3_(arg3),
+      arg4_(arg4),
+      arg5_(arg5)
+  {
+  }
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+  binder5(const binder5& other)
+    : handler_(other.handler_),
+      arg1_(other.arg1_),
+      arg2_(other.arg2_),
+      arg3_(other.arg3_),
+      arg4_(other.arg4_),
+      arg5_(other.arg5_)
+  {
+  }
+
+  binder5(binder5&& other)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(other.handler_)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(other.arg1_)),
+      arg2_(BOOST_ASIO_MOVE_CAST(Arg2)(other.arg2_)),
+      arg3_(BOOST_ASIO_MOVE_CAST(Arg3)(other.arg3_)),
+      arg4_(BOOST_ASIO_MOVE_CAST(Arg4)(other.arg4_)),
+      arg5_(BOOST_ASIO_MOVE_CAST(Arg5)(other.arg5_))
+  {
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+  void operator()()
+  {
+    handler_(static_cast<const Arg1&>(arg1_),
+        static_cast<const Arg2&>(arg2_), static_cast<const Arg3&>(arg3_),
+        static_cast<const Arg4&>(arg4_), static_cast<const Arg5&>(arg5_));
+  }
+
+  void operator()() const
+  {
+    handler_(arg1_, arg2_, arg3_, arg4_, arg5_);
+  }
+
+//private:
+  Handler handler_;
+  Arg1 arg1_;
+  Arg2 arg2_;
+  Arg3 arg3_;
+  Arg4 arg4_;
+  Arg5 arg5_;
+};
+
+template <typename Handler, typename Arg1, typename Arg2,
+    typename Arg3, typename Arg4, typename Arg5>
+inline void* asio_handler_allocate(std::size_t size,
+    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
+{
+  return boost_asio_handler_alloc_helpers::allocate(
+      size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2,
+    typename Arg3, typename Arg4, typename Arg5>
+inline void asio_handler_deallocate(void* pointer, std::size_t size,
+    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
+{
+  boost_asio_handler_alloc_helpers::deallocate(
+      pointer, size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2,
+    typename Arg3, typename Arg4, typename Arg5>
+inline bool asio_handler_is_continuation(
+    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
+{
+  return boost_asio_handler_cont_helpers::is_continuation(
+      this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4, typename Arg5>
+inline void asio_handler_invoke(Function& function,
+    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1,
+    typename Arg2, typename Arg3, typename Arg4, typename Arg5>
+inline void asio_handler_invoke(const Function& function,
+    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      function, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2,
+    typename Arg3, typename Arg4, typename Arg5>
+inline binder5<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4, Arg5>
+bind_handler(BOOST_ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1,
+    const Arg2& arg2, const Arg3& arg3, const Arg4& arg4, const Arg5& arg5)
+{
+  return binder5<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4, Arg5>(0,
+      BOOST_ASIO_MOVE_CAST(Handler)(handler), arg1, arg2, arg3, arg4, arg5);
+}
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+
+template <typename Handler, typename Arg1>
+class move_binder1
+{
+public:
+  move_binder1(int, BOOST_ASIO_MOVE_ARG(Handler) handler,
+      BOOST_ASIO_MOVE_ARG(Arg1) arg1)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(arg1))
+  {
+  }
+
+  move_binder1(move_binder1&& other)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(other.handler_)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(other.arg1_))
+  {
+  }
+
+  void operator()()
+  {
+    handler_(BOOST_ASIO_MOVE_CAST(Arg1)(arg1_));
+  }
+
+//private:
+  Handler handler_;
+  Arg1 arg1_;
+};
+
+template <typename Handler, typename Arg1>
+inline void* asio_handler_allocate(std::size_t size,
+    move_binder1<Handler, Arg1>* this_handler)
+{
+  return boost_asio_handler_alloc_helpers::allocate(
+      size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1>
+inline void asio_handler_deallocate(void* pointer, std::size_t size,
+    move_binder1<Handler, Arg1>* this_handler)
+{
+  boost_asio_handler_alloc_helpers::deallocate(
+      pointer, size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1>
+inline bool asio_handler_is_continuation(
+    move_binder1<Handler, Arg1>* this_handler)
+{
+  return boost_asio_handler_cont_helpers::is_continuation(
+      this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1>
+inline void asio_handler_invoke(BOOST_ASIO_MOVE_ARG(Function) function,
+    move_binder1<Handler, Arg1>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      BOOST_ASIO_MOVE_CAST(Function)(function), this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2>
+class move_binder2
+{
+public:
+  move_binder2(int, BOOST_ASIO_MOVE_ARG(Handler) handler,
+      const Arg1& arg1, BOOST_ASIO_MOVE_ARG(Arg2) arg2)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      arg1_(arg1),
+      arg2_(BOOST_ASIO_MOVE_CAST(Arg2)(arg2))
+  {
+  }
+
+  move_binder2(move_binder2&& other)
+    : handler_(BOOST_ASIO_MOVE_CAST(Handler)(other.handler_)),
+      arg1_(BOOST_ASIO_MOVE_CAST(Arg1)(other.arg1_)),
+      arg2_(BOOST_ASIO_MOVE_CAST(Arg2)(other.arg2_))
+  {
+  }
+
+  void operator()()
+  {
+    handler_(static_cast<const Arg1&>(arg1_),
+        BOOST_ASIO_MOVE_CAST(Arg2)(arg2_));
+  }
+
+//private:
+  Handler handler_;
+  Arg1 arg1_;
+  Arg2 arg2_;
+};
+
+template <typename Handler, typename Arg1, typename Arg2>
+inline void* asio_handler_allocate(std::size_t size,
+    move_binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  return boost_asio_handler_alloc_helpers::allocate(
+      size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2>
+inline void asio_handler_deallocate(void* pointer, std::size_t size,
+    move_binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  boost_asio_handler_alloc_helpers::deallocate(
+      pointer, size, this_handler->handler_);
+}
+
+template <typename Handler, typename Arg1, typename Arg2>
+inline bool asio_handler_is_continuation(
+    move_binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  return boost_asio_handler_cont_helpers::is_continuation(
+      this_handler->handler_);
+}
+
+template <typename Function, typename Handler, typename Arg1, typename Arg2>
+inline void asio_handler_invoke(BOOST_ASIO_MOVE_ARG(Function) function,
+    move_binder2<Handler, Arg1, Arg2>* this_handler)
+{
+  boost_asio_handler_invoke_helpers::invoke(
+      BOOST_ASIO_MOVE_CAST(Function)(function), this_handler->handler_);
+}
+
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+} // namespace detail
+
+template <typename Handler, typename Arg1, typename Allocator>
+struct associated_allocator<detail::binder1<Handler, Arg1>, Allocator>
+{
+  typedef typename associated_allocator<Handler, Allocator>::type type;
+
+  static type get(const detail::binder1<Handler, Arg1>& h,
+      const Allocator& a = Allocator()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
+  }
+};
+
+template <typename Handler, typename Arg1, typename Arg2, typename Allocator>
+struct associated_allocator<detail::binder2<Handler, Arg1, Arg2>, Allocator>
+{
+  typedef typename associated_allocator<Handler, Allocator>::type type;
+
+  static type get(const detail::binder2<Handler, Arg1, Arg2>& h,
+      const Allocator& a = Allocator()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
+  }
+};
+
+template <typename Handler, typename Arg1, typename Executor>
+struct associated_executor<detail::binder1<Handler, Arg1>, Executor>
+{
+  typedef typename associated_executor<Handler, Executor>::type type;
+
+  static type get(const detail::binder1<Handler, Arg1>& h,
+      const Executor& ex = Executor()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_executor<Handler, Executor>::get(h.handler_, ex);
+  }
+};
+
+template <typename Handler, typename Arg1, typename Arg2, typename Executor>
+struct associated_executor<detail::binder2<Handler, Arg1, Arg2>, Executor>
+{
+  typedef typename associated_executor<Handler, Executor>::type type;
+
+  static type get(const detail::binder2<Handler, Arg1, Arg2>& h,
+      const Executor& ex = Executor()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_executor<Handler, Executor>::get(h.handler_, ex);
+  }
+};
+
+#if defined(BOOST_ASIO_HAS_MOVE)
+
+template <typename Handler, typename Arg1, typename Allocator>
+struct associated_allocator<detail::move_binder1<Handler, Arg1>, Allocator>
+{
+  typedef typename associated_allocator<Handler, Allocator>::type type;
+
+  static type get(const detail::move_binder1<Handler, Arg1>& h,
+      const Allocator& a = Allocator()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
+  }
+};
+
+template <typename Handler, typename Arg1, typename Arg2, typename Allocator>
+struct associated_allocator<
+    detail::move_binder2<Handler, Arg1, Arg2>, Allocator>
+{
+  typedef typename associated_allocator<Handler, Allocator>::type type;
+
+  static type get(const detail::move_binder2<Handler, Arg1, Arg2>& h,
+      const Allocator& a = Allocator()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
+  }
+};
+
+template <typename Handler, typename Arg1, typename Executor>
+struct associated_executor<detail::move_binder1<Handler, Arg1>, Executor>
+{
+  typedef typename associated_executor<Handler, Executor>::type type;
+
+  static type get(const detail::move_binder1<Handler, Arg1>& h,
+      const Executor& ex = Executor()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_executor<Handler, Executor>::get(h.handler_, ex);
+  }
+};
+
+template <typename Handler, typename Arg1, typename Arg2, typename Executor>
+struct associated_executor<detail::move_binder2<Handler, Arg1, Arg2>, Executor>
+{
+  typedef typename associated_executor<Handler, Executor>::type type;
+
+  static type get(const detail::move_binder2<Handler, Arg1, Arg2>& h,
+      const Executor& ex = Executor()) BOOST_ASIO_NOEXCEPT
+  {
+    return associated_executor<Handler, Executor>::get(h.handler_, ex);
+  }
+};
+
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_BIND_HANDLER_HPP

boost/asio/detail/buffer_resize_guard.hpp

@@ -0,0 +1,68 @@
+//
+// detail/buffer_resize_guard.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_BUFFER_RESIZE_GUARD_HPP
+#define BOOST_ASIO_DETAIL_BUFFER_RESIZE_GUARD_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/limits.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// Helper class to manage buffer resizing in an exception safe way.
+template <typename Buffer>
+class buffer_resize_guard
+{
+public:
+  // Constructor.
+  buffer_resize_guard(Buffer& buffer)
+    : buffer_(buffer),
+      old_size_(buffer.size())
+  {
+  }
+
+  // Destructor rolls back the buffer resize unless commit was called.
+  ~buffer_resize_guard()
+  {
+    if (old_size_ != (std::numeric_limits<size_t>::max)())
+    {
+      buffer_.resize(old_size_);
+    }
+  }
+
+  // Commit the resize transaction.
+  void commit()
+  {
+    old_size_ = (std::numeric_limits<size_t>::max)();
+  }
+
+private:
+  // The buffer being managed.
+  Buffer& buffer_;
+
+  // The size of the buffer at the time the guard was constructed.
+  size_t old_size_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_BUFFER_RESIZE_GUARD_HPP

boost/asio/detail/buffer_sequence_adapter.hpp

@@ -0,0 +1,546 @@
+//
+// detail/buffer_sequence_adapter.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
+#define BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/detail/array_fwd.hpp>
+#include <boost/asio/detail/socket_types.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class buffer_sequence_adapter_base
+{
+#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
+public:
+  // The maximum number of buffers to support in a single operation.
+  enum { max_buffers = 1 };
+
+protected:
+  typedef Windows::Storage::Streams::IBuffer^ native_buffer_type;
+
+  BOOST_ASIO_DECL static void init_native_buffer(
+      native_buffer_type& buf,
+      const boost::asio::mutable_buffer& buffer);
+
+  BOOST_ASIO_DECL static void init_native_buffer(
+      native_buffer_type& buf,
+      const boost::asio::const_buffer& buffer);
+#elif defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
+public:
+  // The maximum number of buffers to support in a single operation.
+  enum { max_buffers = 64 < max_iov_len ? 64 : max_iov_len };
+
+protected:
+  typedef WSABUF native_buffer_type;
+
+  static void init_native_buffer(WSABUF& buf,
+      const boost::asio::mutable_buffer& buffer)
+  {
+    buf.buf = static_cast<char*>(buffer.data());
+    buf.len = static_cast<ULONG>(buffer.size());
+  }
+
+  static void init_native_buffer(WSABUF& buf,
+      const boost::asio::const_buffer& buffer)
+  {
+    buf.buf = const_cast<char*>(static_cast<const char*>(buffer.data()));
+    buf.len = static_cast<ULONG>(buffer.size());
+  }
+#else // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
+public:
+  // The maximum number of buffers to support in a single operation.
+  enum { max_buffers = 64 < max_iov_len ? 64 : max_iov_len };
+
+protected:
+  typedef iovec native_buffer_type;
+
+  static void init_iov_base(void*& base, void* addr)
+  {
+    base = addr;
+  }
+
+  template <typename T>
+  static void init_iov_base(T& base, void* addr)
+  {
+    base = static_cast<T>(addr);
+  }
+
+  static void init_native_buffer(iovec& iov,
+      const boost::asio::mutable_buffer& buffer)
+  {
+    init_iov_base(iov.iov_base, buffer.data());
+    iov.iov_len = buffer.size();
+  }
+
+  static void init_native_buffer(iovec& iov,
+      const boost::asio::const_buffer& buffer)
+  {
+    init_iov_base(iov.iov_base, const_cast<void*>(buffer.data()));
+    iov.iov_len = buffer.size();
+  }
+#endif // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
+};
+
+// Helper class to translate buffers into the native buffer representation.
+template <typename Buffer, typename Buffers>
+class buffer_sequence_adapter
+  : buffer_sequence_adapter_base
+{
+public:
+  explicit buffer_sequence_adapter(const Buffers& buffer_sequence)
+    : count_(0), total_buffer_size_(0)
+  {
+    buffer_sequence_adapter::init(
+        boost::asio::buffer_sequence_begin(buffer_sequence),
+        boost::asio::buffer_sequence_end(buffer_sequence));
+  }
+
+  native_buffer_type* buffers()
+  {
+    return buffers_;
+  }
+
+  std::size_t count() const
+  {
+    return count_;
+  }
+
+  std::size_t total_size() const
+  {
+    return total_buffer_size_;
+  }
+
+  bool all_empty() const
+  {
+    return total_buffer_size_ == 0;
+  }
+
+  static bool all_empty(const Buffers& buffer_sequence)
+  {
+    return buffer_sequence_adapter::all_empty(
+        boost::asio::buffer_sequence_begin(buffer_sequence),
+        boost::asio::buffer_sequence_end(buffer_sequence));
+  }
+
+  static void validate(const Buffers& buffer_sequence)
+  {
+    buffer_sequence_adapter::validate(
+        boost::asio::buffer_sequence_begin(buffer_sequence),
+        boost::asio::buffer_sequence_end(buffer_sequence));
+  }
+
+  static Buffer first(const Buffers& buffer_sequence)
+  {
+    return buffer_sequence_adapter::first(
+        boost::asio::buffer_sequence_begin(buffer_sequence),
+        boost::asio::buffer_sequence_end(buffer_sequence));
+  }
+
+private:
+  template <typename Iterator>
+  void init(Iterator begin, Iterator end)
+  {
+    Iterator iter = begin;
+    for (; iter != end && count_ < max_buffers; ++iter, ++count_)
+    {
+      Buffer buffer(*iter);
+      init_native_buffer(buffers_[count_], buffer);
+      total_buffer_size_ += buffer.size();
+    }
+  }
+
+  template <typename Iterator>
+  static bool all_empty(Iterator begin, Iterator end)
+  {
+    Iterator iter = begin;
+    std::size_t i = 0;
+    for (; iter != end && i < max_buffers; ++iter, ++i)
+      if (Buffer(*iter).size() > 0)
+        return false;
+    return true;
+  }
+
+  template <typename Iterator>
+  static void validate(Iterator begin, Iterator end)
+  {
+    Iterator iter = begin;
+    for (; iter != end; ++iter)
+    {
+      Buffer buffer(*iter);
+      buffer.data();
+    }
+  }
+
+  template <typename Iterator>
+  static Buffer first(Iterator begin, Iterator end)
+  {
+    Iterator iter = begin;
+    for (; iter != end; ++iter)
+    {
+      Buffer buffer(*iter);
+      if (buffer.size() != 0)
+        return buffer;
+    }
+    return Buffer();
+  }
+
+  native_buffer_type buffers_[max_buffers];
+  std::size_t count_;
+  std::size_t total_buffer_size_;
+};
+
+template <typename Buffer>
+class buffer_sequence_adapter<Buffer, boost::asio::mutable_buffer>
+  : buffer_sequence_adapter_base
+{
+public:
+  explicit buffer_sequence_adapter(
+      const boost::asio::mutable_buffer& buffer_sequence)
+  {
+    init_native_buffer(buffer_, Buffer(buffer_sequence));
+    total_buffer_size_ = buffer_sequence.size();
+  }
+
+  native_buffer_type* buffers()
+  {
+    return &buffer_;
+  }
+
+  std::size_t count() const
+  {
+    return 1;
+  }
+
+  std::size_t total_size() const
+  {
+    return total_buffer_size_;
+  }
+
+  bool all_empty() const
+  {
+    return total_buffer_size_ == 0;
+  }
+
+  static bool all_empty(const boost::asio::mutable_buffer& buffer_sequence)
+  {
+    return buffer_sequence.size() == 0;
+  }
+
+  static void validate(const boost::asio::mutable_buffer& buffer_sequence)
+  {
+    buffer_sequence.data();
+  }
+
+  static Buffer first(const boost::asio::mutable_buffer& buffer_sequence)
+  {
+    return Buffer(buffer_sequence);
+  }
+
+private:
+  native_buffer_type buffer_;
+  std::size_t total_buffer_size_;
+};
+
+template <typename Buffer>
+class buffer_sequence_adapter<Buffer, boost::asio::const_buffer>
+  : buffer_sequence_adapter_base
+{
+public:
+  explicit buffer_sequence_adapter(
+      const boost::asio::const_buffer& buffer_sequence)
+  {
+    init_native_buffer(buffer_, Buffer(buffer_sequence));
+    total_buffer_size_ = buffer_sequence.size();
+  }
+
+  native_buffer_type* buffers()
+  {
+    return &buffer_;
+  }
+
+  std::size_t count() const
+  {
+    return 1;
+  }
+
+  std::size_t total_size() const
+  {
+    return total_buffer_size_;
+  }
+
+  bool all_empty() const
+  {
+    return total_buffer_size_ == 0;
+  }
+
+  static bool all_empty(const boost::asio::const_buffer& buffer_sequence)
+  {
+    return buffer_sequence.size() == 0;
+  }
+
+  static void validate(const boost::asio::const_buffer& buffer_sequence)
+  {
+    buffer_sequence.data();
+  }
+
+  static Buffer first(const boost::asio::const_buffer& buffer_sequence)
+  {
+    return Buffer(buffer_sequence);
+  }
+
+private:
+  native_buffer_type buffer_;
+  std::size_t total_buffer_size_;
+};
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+
+template <typename Buffer>
+class buffer_sequence_adapter<Buffer, boost::asio::mutable_buffers_1>
+  : buffer_sequence_adapter_base
+{
+public:
+  explicit buffer_sequence_adapter(
+      const boost::asio::mutable_buffers_1& buffer_sequence)
+  {
+    init_native_buffer(buffer_, Buffer(buffer_sequence));
+    total_buffer_size_ = buffer_sequence.size();
+  }
+
+  native_buffer_type* buffers()
+  {
+    return &buffer_;
+  }
+
+  std::size_t count() const
+  {
+    return 1;
+  }
+
+  std::size_t total_size() const
+  {
+    return total_buffer_size_;
+  }
+
+  bool all_empty() const
+  {
+    return total_buffer_size_ == 0;
+  }
+
+  static bool all_empty(const boost::asio::mutable_buffers_1& buffer_sequence)
+  {
+    return buffer_sequence.size() == 0;
+  }
+
+  static void validate(const boost::asio::mutable_buffers_1& buffer_sequence)
+  {
+    buffer_sequence.data();
+  }
+
+  static Buffer first(const boost::asio::mutable_buffers_1& buffer_sequence)
+  {
+    return Buffer(buffer_sequence);
+  }
+
+private:
+  native_buffer_type buffer_;
+  std::size_t total_buffer_size_;
+};
+
+template <typename Buffer>
+class buffer_sequence_adapter<Buffer, boost::asio::const_buffers_1>
+  : buffer_sequence_adapter_base
+{
+public:
+  explicit buffer_sequence_adapter(
+      const boost::asio::const_buffers_1& buffer_sequence)
+  {
+    init_native_buffer(buffer_, Buffer(buffer_sequence));
+    total_buffer_size_ = buffer_sequence.size();
+  }
+
+  native_buffer_type* buffers()
+  {
+    return &buffer_;
+  }
+
+  std::size_t count() const
+  {
+    return 1;
+  }
+
+  std::size_t total_size() const
+  {
+    return total_buffer_size_;
+  }
+
+  bool all_empty() const
+  {
+    return total_buffer_size_ == 0;
+  }
+
+  static bool all_empty(const boost::asio::const_buffers_1& buffer_sequence)
+  {
+    return buffer_sequence.size() == 0;
+  }
+
+  static void validate(const boost::asio::const_buffers_1& buffer_sequence)
+  {
+    buffer_sequence.data();
+  }
+
+  static Buffer first(const boost::asio::const_buffers_1& buffer_sequence)
+  {
+    return Buffer(buffer_sequence);
+  }
+
+private:
+  native_buffer_type buffer_;
+  std::size_t total_buffer_size_;
+};
+
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+template <typename Buffer, typename Elem>
+class buffer_sequence_adapter<Buffer, boost::array<Elem, 2> >
+  : buffer_sequence_adapter_base
+{
+public:
+  explicit buffer_sequence_adapter(
+      const boost::array<Elem, 2>& buffer_sequence)
+  {
+    init_native_buffer(buffers_[0], Buffer(buffer_sequence[0]));
+    init_native_buffer(buffers_[1], Buffer(buffer_sequence[1]));
+    total_buffer_size_ = buffer_sequence[0].size() + buffer_sequence[1].size();
+  }
+
+  native_buffer_type* buffers()
+  {
+    return buffers_;
+  }
+
+  std::size_t count() const
+  {
+    return 2;
+  }
+
+  std::size_t total_size() const
+  {
+    return total_buffer_size_;
+  }
+
+  bool all_empty() const
+  {
+    return total_buffer_size_ == 0;
+  }
+
+  static bool all_empty(const boost::array<Elem, 2>& buffer_sequence)
+  {
+    return buffer_sequence[0].size() == 0 && buffer_sequence[1].size() == 0;
+  }
+
+  static void validate(const boost::array<Elem, 2>& buffer_sequence)
+  {
+    buffer_sequence[0].data();
+    buffer_sequence[1].data();
+  }
+
+  static Buffer first(const boost::array<Elem, 2>& buffer_sequence)
+  {
+    return Buffer(buffer_sequence[0].size() != 0
+        ? buffer_sequence[0] : buffer_sequence[1]);
+  }
+
+private:
+  native_buffer_type buffers_[2];
+  std::size_t total_buffer_size_;
+};
+
+#if defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+template <typename Buffer, typename Elem>
+class buffer_sequence_adapter<Buffer, std::array<Elem, 2> >
+  : buffer_sequence_adapter_base
+{
+public:
+  explicit buffer_sequence_adapter(
+      const std::array<Elem, 2>& buffer_sequence)
+  {
+    init_native_buffer(buffers_[0], Buffer(buffer_sequence[0]));
+    init_native_buffer(buffers_[1], Buffer(buffer_sequence[1]));
+    total_buffer_size_ = buffer_sequence[0].size() + buffer_sequence[1].size();
+  }
+
+  native_buffer_type* buffers()
+  {
+    return buffers_;
+  }
+
+  std::size_t count() const
+  {
+    return 2;
+  }
+
+  std::size_t total_size() const
+  {
+    return total_buffer_size_;
+  }
+
+  bool all_empty() const
+  {
+    return total_buffer_size_ == 0;
+  }
+
+  static bool all_empty(const std::array<Elem, 2>& buffer_sequence)
+  {
+    return buffer_sequence[0].size() == 0 && buffer_sequence[1].size() == 0;
+  }
+
+  static void validate(const std::array<Elem, 2>& buffer_sequence)
+  {
+    buffer_sequence[0].data();
+    buffer_sequence[1].data();
+  }
+
+  static Buffer first(const std::array<Elem, 2>& buffer_sequence)
+  {
+    return Buffer(buffer_sequence[0].size() != 0
+        ? buffer_sequence[0] : buffer_sequence[1]);
+  }
+
+private:
+  native_buffer_type buffers_[2];
+  std::size_t total_buffer_size_;
+};
+
+#endif // defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#if defined(BOOST_ASIO_HEADER_ONLY)
+# include <boost/asio/detail/impl/buffer_sequence_adapter.ipp>
+#endif // defined(BOOST_ASIO_HEADER_ONLY)
+
+#endif // BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP

boost/asio/detail/buffered_stream_storage.hpp

@@ -0,0 +1,128 @@
+//
+// detail/buffered_stream_storage.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP
+#define BOOST_ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/detail/assert.hpp>
+#include <cstddef>
+#include <cstring>
+#include <vector>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class buffered_stream_storage
+{
+public:
+  // The type of the bytes stored in the buffer.
+  typedef unsigned char byte_type;
+
+  // The type used for offsets into the buffer.
+  typedef std::size_t size_type;
+
+  // Constructor.
+  explicit buffered_stream_storage(std::size_t buffer_capacity)
+    : begin_offset_(0),
+      end_offset_(0),
+      buffer_(buffer_capacity)
+  {
+  }
+
+  /// Clear the buffer.
+  void clear()
+  {
+    begin_offset_ = 0;
+    end_offset_ = 0;
+  }
+
+  // Return a pointer to the beginning of the unread data.
+  mutable_buffer data()
+  {
+    return boost::asio::buffer(buffer_) + begin_offset_;
+  }
+
+  // Return a pointer to the beginning of the unread data.
+  const_buffer data() const
+  {
+    return boost::asio::buffer(buffer_) + begin_offset_;
+  }
+
+  // Is there no unread data in the buffer.
+  bool empty() const
+  {
+    return begin_offset_ == end_offset_;
+  }
+
+  // Return the amount of unread data the is in the buffer.
+  size_type size() const
+  {
+    return end_offset_ - begin_offset_;
+  }
+
+  // Resize the buffer to the specified length.
+  void resize(size_type length)
+  {
+    BOOST_ASIO_ASSERT(length <= capacity());
+    if (begin_offset_ + length <= capacity())
+    {
+      end_offset_ = begin_offset_ + length;
+    }
+    else
+    {
+      using namespace std; // For memmove.
+      memmove(&buffer_[0], &buffer_[0] + begin_offset_, size());
+      end_offset_ = length;
+      begin_offset_ = 0;
+    }
+  }
+
+  // Return the maximum size for data in the buffer.
+  size_type capacity() const
+  {
+    return buffer_.size();
+  }
+
+  // Consume multiple bytes from the beginning of the buffer.
+  void consume(size_type count)
+  {
+    BOOST_ASIO_ASSERT(begin_offset_ + count <= end_offset_);
+    begin_offset_ += count;
+    if (empty())
+      clear();
+  }
+
+private:
+  // The offset to the beginning of the unread data.
+  size_type begin_offset_;
+
+  // The offset to the end of the unread data.
+  size_type end_offset_;
+  
+  // The data in the buffer.
+  std::vector<byte_type> buffer_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP

boost/asio/detail/call_stack.hpp

@@ -0,0 +1,127 @@
+//
+// detail/call_stack.hpp
+// ~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CALL_STACK_HPP
+#define BOOST_ASIO_DETAIL_CALL_STACK_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/detail/tss_ptr.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// Helper class to determine whether or not the current thread is inside an
+// invocation of io_context::run() for a specified io_context object.
+template <typename Key, typename Value = unsigned char>
+class call_stack
+{
+public:
+  // Context class automatically pushes the key/value pair on to the stack.
+  class context
+    : private noncopyable
+  {
+  public:
+    // Push the key on to the stack.
+    explicit context(Key* k)
+      : key_(k),
+        next_(call_stack<Key, Value>::top_)
+    {
+      value_ = reinterpret_cast<unsigned char*>(this);
+      call_stack<Key, Value>::top_ = this;
+    }
+
+    // Push the key/value pair on to the stack.
+    context(Key* k, Value& v)
+      : key_(k),
+        value_(&v),
+        next_(call_stack<Key, Value>::top_)
+    {
+      call_stack<Key, Value>::top_ = this;
+    }
+
+    // Pop the key/value pair from the stack.
+    ~context()
+    {
+      call_stack<Key, Value>::top_ = next_;
+    }
+
+    // Find the next context with the same key.
+    Value* next_by_key() const
+    {
+      context* elem = next_;
+      while (elem)
+      {
+        if (elem->key_ == key_)
+          return elem->value_;
+        elem = elem->next_;
+      }
+      return 0;
+    }
+
+  private:
+    friend class call_stack<Key, Value>;
+
+    // The key associated with the context.
+    Key* key_;
+
+    // The value associated with the context.
+    Value* value_;
+
+    // The next element in the stack.
+    context* next_;
+  };
+
+  friend class context;
+
+  // Determine whether the specified owner is on the stack. Returns address of
+  // key if present, 0 otherwise.
+  static Value* contains(Key* k)
+  {
+    context* elem = top_;
+    while (elem)
+    {
+      if (elem->key_ == k)
+        return elem->value_;
+      elem = elem->next_;
+    }
+    return 0;
+  }
+
+  // Obtain the value at the top of the stack.
+  static Value* top()
+  {
+    context* elem = top_;
+    return elem ? elem->value_ : 0;
+  }
+
+private:
+  // The top of the stack of calls for the current thread.
+  static tss_ptr<context> top_;
+};
+
+template <typename Key, typename Value>
+tss_ptr<typename call_stack<Key, Value>::context>
+call_stack<Key, Value>::top_;
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_CALL_STACK_HPP

boost/asio/detail/chrono.hpp

@@ -0,0 +1,68 @@
+//
+// detail/chrono.hpp
+// ~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CHRONO_HPP
+#define BOOST_ASIO_DETAIL_CHRONO_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_STD_CHRONO)
+# include <chrono>
+#elif defined(BOOST_ASIO_HAS_BOOST_CHRONO)
+# include <boost/chrono/system_clocks.hpp>
+#endif // defined(BOOST_ASIO_HAS_BOOST_CHRONO)
+
+namespace boost {
+namespace asio {
+namespace chrono {
+
+#if defined(BOOST_ASIO_HAS_STD_CHRONO)
+using std::chrono::duration;
+using std::chrono::time_point;
+using std::chrono::duration_cast;
+using std::chrono::nanoseconds;
+using std::chrono::microseconds;
+using std::chrono::milliseconds;
+using std::chrono::seconds;
+using std::chrono::minutes;
+using std::chrono::hours;
+using std::chrono::time_point_cast;
+#if defined(BOOST_ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK)
+typedef std::chrono::monotonic_clock steady_clock;
+#else // defined(BOOST_ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK)
+using std::chrono::steady_clock;
+#endif // defined(BOOST_ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK)
+using std::chrono::system_clock;
+using std::chrono::high_resolution_clock;
+#elif defined(BOOST_ASIO_HAS_BOOST_CHRONO)
+using boost::chrono::duration;
+using boost::chrono::time_point;
+using boost::chrono::duration_cast;
+using boost::chrono::nanoseconds;
+using boost::chrono::microseconds;
+using boost::chrono::milliseconds;
+using boost::chrono::seconds;
+using boost::chrono::minutes;
+using boost::chrono::hours;
+using boost::chrono::time_point_cast;
+using boost::chrono::system_clock;
+using boost::chrono::steady_clock;
+using boost::chrono::high_resolution_clock;
+#endif // defined(BOOST_ASIO_HAS_BOOST_CHRONO)
+
+} // namespace chrono
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_CHRONO_HPP

boost/asio/detail/chrono_time_traits.hpp

@@ -0,0 +1,192 @@
+//
+// detail/chrono_time_traits.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CHRONO_TIME_TRAITS_HPP
+#define BOOST_ASIO_DETAIL_CHRONO_TIME_TRAITS_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/cstdint.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// Helper template to compute the greatest common divisor.
+template <int64_t v1, int64_t v2>
+struct gcd { enum { value = gcd<v2, v1 % v2>::value }; };
+
+template <int64_t v1>
+struct gcd<v1, 0> { enum { value = v1 }; };
+
+// Adapts std::chrono clocks for use with a deadline timer.
+template <typename Clock, typename WaitTraits>
+struct chrono_time_traits
+{
+  // The clock type.
+  typedef Clock clock_type;
+
+  // The duration type of the clock.
+  typedef typename clock_type::duration duration_type;
+
+  // The time point type of the clock.
+  typedef typename clock_type::time_point time_type;
+
+  // The period of the clock.
+  typedef typename duration_type::period period_type;
+
+  // Get the current time.
+  static time_type now()
+  {
+    return clock_type::now();
+  }
+
+  // Add a duration to a time.
+  static time_type add(const time_type& t, const duration_type& d)
+  {
+    const time_type epoch;
+    if (t >= epoch)
+    {
+      if ((time_type::max)() - t < d)
+        return (time_type::max)();
+    }
+    else // t < epoch
+    {
+      if (-(t - (time_type::min)()) > d)
+        return (time_type::min)();
+    }
+
+    return t + d;
+  }
+
+  // Subtract one time from another.
+  static duration_type subtract(const time_type& t1, const time_type& t2)
+  {
+    const time_type epoch;
+    if (t1 >= epoch)
+    {
+      if (t2 >= epoch)
+      {
+        return t1 - t2;
+      }
+      else if (t2 == (time_type::min)())
+      {
+        return (duration_type::max)();
+      }
+      else if ((time_type::max)() - t1 < epoch - t2)
+      {
+        return (duration_type::max)();
+      }
+      else
+      {
+        return t1 - t2;
+      }
+    }
+    else // t1 < epoch
+    {
+      if (t2 < epoch)
+      {
+        return t1 - t2;
+      }
+      else if (t1 == (time_type::min)())
+      {
+        return (duration_type::min)();
+      }
+      else if ((time_type::max)() - t2 < epoch - t1)
+      {
+        return (duration_type::min)();
+      }
+      else
+      {
+        return -(t2 - t1);
+      }
+    }
+  }
+
+  // Test whether one time is less than another.
+  static bool less_than(const time_type& t1, const time_type& t2)
+  {
+    return t1 < t2;
+  }
+
+  // Implement just enough of the posix_time::time_duration interface to supply
+  // what the timer_queue requires.
+  class posix_time_duration
+  {
+  public:
+    explicit posix_time_duration(const duration_type& d)
+      : d_(d)
+    {
+    }
+
+    int64_t ticks() const
+    {
+      return d_.count();
+    }
+
+    int64_t total_seconds() const
+    {
+      return duration_cast<1, 1>();
+    }
+
+    int64_t total_milliseconds() const
+    {
+      return duration_cast<1, 1000>();
+    }
+
+    int64_t total_microseconds() const
+    {
+      return duration_cast<1, 1000000>();
+    }
+
+  private:
+    template <int64_t Num, int64_t Den>
+    int64_t duration_cast() const
+    {
+      const int64_t num1 = period_type::num / gcd<period_type::num, Num>::value;
+      const int64_t num2 = Num / gcd<period_type::num, Num>::value;
+
+      const int64_t den1 = period_type::den / gcd<period_type::den, Den>::value;
+      const int64_t den2 = Den / gcd<period_type::den, Den>::value;
+
+      const int64_t num = num1 * den2;
+      const int64_t den = num2 * den1;
+
+      if (num == 1 && den == 1)
+        return ticks();
+      else if (num != 1 && den == 1)
+        return ticks() * num;
+      else if (num == 1 && period_type::den != 1)
+        return ticks() / den;
+      else
+        return ticks() * num / den;
+    }
+
+    duration_type d_;
+  };
+
+  // Convert to POSIX duration type.
+  static posix_time_duration to_posix_duration(const duration_type& d)
+  {
+    return posix_time_duration(WaitTraits::to_wait_duration(d));
+  }
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_CHRONO_TIME_TRAITS_HPP

boost/asio/detail/completion_handler.hpp

@@ -0,0 +1,85 @@
+//
+// detail/completion_handler.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_COMPLETION_HANDLER_HPP
+#define BOOST_ASIO_DETAIL_COMPLETION_HANDLER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/fenced_block.hpp>
+#include <boost/asio/detail/handler_alloc_helpers.hpp>
+#include <boost/asio/detail/handler_work.hpp>
+#include <boost/asio/detail/memory.hpp>
+#include <boost/asio/detail/operation.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename Handler>
+class completion_handler : public operation
+{
+public:
+  BOOST_ASIO_DEFINE_HANDLER_PTR(completion_handler);
+
+  completion_handler(Handler& h)
+    : operation(&completion_handler::do_complete),
+      handler_(BOOST_ASIO_MOVE_CAST(Handler)(h))
+  {
+    handler_work<Handler>::start(handler_);
+  }
+
+  static void do_complete(void* owner, operation* base,
+      const boost::system::error_code& /*ec*/,
+      std::size_t /*bytes_transferred*/)
+  {
+    // Take ownership of the handler object.
+    completion_handler* h(static_cast<completion_handler*>(base));
+    ptr p = { boost::asio::detail::addressof(h->handler_), h, h };
+    handler_work<Handler> w(h->handler_);
+
+    BOOST_ASIO_HANDLER_COMPLETION((*h));
+
+    // Make a copy of the handler so that the memory can be deallocated before
+    // the upcall is made. Even if we're not about to make an upcall, a
+    // sub-object of the handler may be the true owner of the memory associated
+    // with the handler. Consequently, a local copy of the handler is required
+    // to ensure that any owning sub-object remains valid until after we have
+    // deallocated the memory here.
+    Handler handler(BOOST_ASIO_MOVE_CAST(Handler)(h->handler_));
+    p.h = boost::asio::detail::addressof(handler);
+    p.reset();
+
+    // Make the upcall if required.
+    if (owner)
+    {
+      fenced_block b(fenced_block::half);
+      BOOST_ASIO_HANDLER_INVOCATION_BEGIN(());
+      w.complete(handler, handler);
+      BOOST_ASIO_HANDLER_INVOCATION_END;
+    }
+  }
+
+private:
+  Handler handler_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_COMPLETION_HANDLER_HPP

boost/asio/detail/concurrency_hint.hpp

@@ -0,0 +1,94 @@
+//
+// detail/concurrency_hint.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CONCURRENCY_HINT_HPP
+#define BOOST_ASIO_DETAIL_CONCURRENCY_HINT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+
+// The concurrency hint ID and mask are used to identify when a "well-known"
+// concurrency hint value has been passed to the io_context.
+#define BOOST_ASIO_CONCURRENCY_HINT_ID 0xA5100000u
+#define BOOST_ASIO_CONCURRENCY_HINT_ID_MASK 0xFFFF0000u
+
+// If set, this bit indicates that the scheduler should perform locking.
+#define BOOST_ASIO_CONCURRENCY_HINT_LOCKING_SCHEDULER 0x1u
+
+// If set, this bit indicates that the reactor should perform locking when
+// managing descriptor registrations.
+#define BOOST_ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_REGISTRATION 0x2u
+
+// If set, this bit indicates that the reactor should perform locking for I/O.
+#define BOOST_ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_IO 0x4u
+
+// Helper macro to determine if we have a special concurrency hint.
+#define BOOST_ASIO_CONCURRENCY_HINT_IS_SPECIAL(hint) \
+  ((static_cast<unsigned>(hint) \
+    & BOOST_ASIO_CONCURRENCY_HINT_ID_MASK) \
+      == BOOST_ASIO_CONCURRENCY_HINT_ID)
+
+// Helper macro to determine if locking is enabled for a given facility.
+#define BOOST_ASIO_CONCURRENCY_HINT_IS_LOCKING(facility, hint) \
+  (((static_cast<unsigned>(hint) \
+    & (BOOST_ASIO_CONCURRENCY_HINT_ID_MASK \
+      | BOOST_ASIO_CONCURRENCY_HINT_LOCKING_ ## facility)) \
+        ^ BOOST_ASIO_CONCURRENCY_HINT_ID) != 0)
+
+// This special concurrency hint disables locking in both the scheduler and
+// reactor I/O. This hint has the following restrictions:
+//
+// - Care must be taken to ensure that all operations on the io_context and any
+//   of its associated I/O objects (such as sockets and timers) occur in only
+//   one thread at a time.
+//
+// - Asynchronous resolve operations fail with operation_not_supported.
+//
+// - If a signal_set is used with the io_context, signal_set objects cannot be
+//   used with any other io_context in the program.
+#define BOOST_ASIO_CONCURRENCY_HINT_UNSAFE \
+  static_cast<int>(BOOST_ASIO_CONCURRENCY_HINT_ID)
+
+// This special concurrency hint disables locking in the reactor I/O. This hint
+// has the following restrictions:
+//
+// - Care must be taken to ensure that run functions on the io_context, and all
+//   operations on the io_context's associated I/O objects (such as sockets and
+//   timers), occur in only one thread at a time.
+#define BOOST_ASIO_CONCURRENCY_HINT_UNSAFE_IO \
+  static_cast<int>(BOOST_ASIO_CONCURRENCY_HINT_ID \
+      | BOOST_ASIO_CONCURRENCY_HINT_LOCKING_SCHEDULER \
+      | BOOST_ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_REGISTRATION)
+
+// The special concurrency hint provides full thread safety.
+#define BOOST_ASIO_CONCURRENCY_HINT_SAFE \
+  static_cast<int>(BOOST_ASIO_CONCURRENCY_HINT_ID \
+      | BOOST_ASIO_CONCURRENCY_HINT_LOCKING_SCHEDULER \
+      | BOOST_ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_REGISTRATION \
+      | BOOST_ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_IO)
+
+// This #define may be overridden at compile time to specify a program-wide
+// default concurrency hint, used by the zero-argument io_context constructor.
+#if !defined(BOOST_ASIO_CONCURRENCY_HINT_DEFAULT)
+# define BOOST_ASIO_CONCURRENCY_HINT_DEFAULT -1
+#endif // !defined(BOOST_ASIO_CONCURRENCY_HINT_DEFAULT)
+
+// This #define may be overridden at compile time to specify a program-wide
+// concurrency hint, used by the one-argument io_context constructor when
+// passed a value of 1.
+#if !defined(BOOST_ASIO_CONCURRENCY_HINT_1)
+# define BOOST_ASIO_CONCURRENCY_HINT_1 1
+#endif // !defined(BOOST_ASIO_CONCURRENCY_HINT_DEFAULT)
+
+#endif // BOOST_ASIO_DETAIL_CONCURRENCY_HINT_HPP

boost/asio/detail/conditionally_enabled_event.hpp

@@ -0,0 +1,114 @@
+//
+// detail/conditionally_enabled_event.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP
+#define BOOST_ASIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/conditionally_enabled_mutex.hpp>
+#include <boost/asio/detail/event.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/detail/null_event.hpp>
+#include <boost/asio/detail/scoped_lock.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// Mutex adapter used to conditionally enable or disable locking.
+class conditionally_enabled_event
+  : private noncopyable
+{
+public:
+  // Constructor.
+  conditionally_enabled_event()
+  {
+  }
+
+  // Destructor.
+  ~conditionally_enabled_event()
+  {
+  }
+
+  // Signal the event. (Retained for backward compatibility.)
+  void signal(conditionally_enabled_mutex::scoped_lock& lock)
+  {
+    if (lock.mutex_.enabled_)
+      event_.signal(lock);
+  }
+
+  // Signal all waiters.
+  void signal_all(conditionally_enabled_mutex::scoped_lock& lock)
+  {
+    if (lock.mutex_.enabled_)
+      event_.signal_all(lock);
+  }
+
+  // Unlock the mutex and signal one waiter.
+  void unlock_and_signal_one(
+      conditionally_enabled_mutex::scoped_lock& lock)
+  {
+    if (lock.mutex_.enabled_)
+      event_.unlock_and_signal_one(lock);
+  }
+
+  // If there's a waiter, unlock the mutex and signal it.
+  bool maybe_unlock_and_signal_one(
+      conditionally_enabled_mutex::scoped_lock& lock)
+  {
+    if (lock.mutex_.enabled_)
+      return event_.maybe_unlock_and_signal_one(lock);
+    else
+      return false;
+  }
+
+  // Reset the event.
+  void clear(conditionally_enabled_mutex::scoped_lock& lock)
+  {
+    if (lock.mutex_.enabled_)
+      event_.clear(lock);
+  }
+
+  // Wait for the event to become signalled.
+  void wait(conditionally_enabled_mutex::scoped_lock& lock)
+  {
+    if (lock.mutex_.enabled_)
+      event_.wait(lock);
+    else
+      null_event().wait(lock);
+  }
+
+  // Timed wait for the event to become signalled.
+  bool wait_for_usec(
+      conditionally_enabled_mutex::scoped_lock& lock, long usec)
+  {
+    if (lock.mutex_.enabled_)
+      return event_.wait_for_usec(lock, usec);
+    else
+      return null_event().wait_for_usec(lock, usec);
+  }
+
+private:
+  boost::asio::detail::event event_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP

boost/asio/detail/conditionally_enabled_mutex.hpp

@@ -0,0 +1,151 @@
+//
+// detail/conditionally_enabled_mutex.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CONDITIONALLY_ENABLED_MUTEX_HPP
+#define BOOST_ASIO_DETAIL_CONDITIONALLY_ENABLED_MUTEX_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/mutex.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/detail/scoped_lock.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// Mutex adapter used to conditionally enable or disable locking.
+class conditionally_enabled_mutex
+  : private noncopyable
+{
+public:
+  // Helper class to lock and unlock a mutex automatically.
+  class scoped_lock
+    : private noncopyable
+  {
+  public:
+    // Tag type used to distinguish constructors.
+    enum adopt_lock_t { adopt_lock };
+
+    // Constructor adopts a lock that is already held.
+    scoped_lock(conditionally_enabled_mutex& m, adopt_lock_t)
+      : mutex_(m),
+        locked_(m.enabled_)
+    {
+    }
+
+    // Constructor acquires the lock.
+    explicit scoped_lock(conditionally_enabled_mutex& m)
+      : mutex_(m)
+    {
+      if (m.enabled_)
+      {
+        mutex_.mutex_.lock();
+        locked_ = true;
+      }
+      else
+        locked_ = false;
+    }
+
+    // Destructor releases the lock.
+    ~scoped_lock()
+    {
+      if (locked_)
+        mutex_.mutex_.unlock();
+    }
+
+    // Explicitly acquire the lock.
+    void lock()
+    {
+      if (mutex_.enabled_ && !locked_)
+      {
+        mutex_.mutex_.lock();
+        locked_ = true;
+      }
+    }
+
+    // Explicitly release the lock.
+    void unlock()
+    {
+      if (locked_)
+      {
+        mutex_.unlock();
+        locked_ = false;
+      }
+    }
+
+    // Test whether the lock is held.
+    bool locked() const
+    {
+      return locked_;
+    }
+
+    // Get the underlying mutex.
+    boost::asio::detail::mutex& mutex()
+    {
+      return mutex_.mutex_;
+    }
+
+  private:
+    friend class conditionally_enabled_event;
+    conditionally_enabled_mutex& mutex_;
+    bool locked_;
+  };
+
+  // Constructor.
+  explicit conditionally_enabled_mutex(bool enabled)
+    : enabled_(enabled)
+  {
+  }
+
+  // Destructor.
+  ~conditionally_enabled_mutex()
+  {
+  }
+
+  // Determine whether locking is enabled.
+  bool enabled() const
+  {
+    return enabled_;
+  }
+
+  // Lock the mutex.
+  void lock()
+  {
+    if (enabled_)
+      mutex_.lock();
+  }
+
+  // Unlock the mutex.
+  void unlock()
+  {
+    if (enabled_)
+      mutex_.unlock();
+  }
+
+private:
+  friend class scoped_lock;
+  friend class conditionally_enabled_event;
+  boost::asio::detail::mutex mutex_;
+  const bool enabled_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_CONDITIONALLY_ENABLED_MUTEX_HPP

boost/asio/detail/consuming_buffers.hpp

@@ -0,0 +1,416 @@
+//
+// detail/consuming_buffers.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CONSUMING_BUFFERS_HPP
+#define BOOST_ASIO_DETAIL_CONSUMING_BUFFERS_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/detail/buffer_sequence_adapter.hpp>
+#include <boost/asio/detail/limits.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+// Helper template to determine the maximum number of prepared buffers.
+template <typename Buffers>
+struct prepared_buffers_max
+{
+  enum { value = buffer_sequence_adapter_base::max_buffers };
+};
+
+template <typename Elem, std::size_t N>
+struct prepared_buffers_max<boost::array<Elem, N> >
+{
+  enum { value = N };
+};
+
+#if defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+template <typename Elem, std::size_t N>
+struct prepared_buffers_max<std::array<Elem, N> >
+{
+  enum { value = N };
+};
+
+#endif // defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+// A buffer sequence used to represent a subsequence of the buffers.
+template <typename Buffer, std::size_t MaxBuffers>
+struct prepared_buffers
+{
+  typedef Buffer value_type;
+  typedef const Buffer* const_iterator;
+
+  enum { max_buffers = MaxBuffers < 16 ? MaxBuffers : 16 };
+
+  prepared_buffers() : count(0) {}
+  const_iterator begin() const { return elems; }
+  const_iterator end() const { return elems + count; }
+
+  Buffer elems[max_buffers];
+  std::size_t count;
+};
+
+// A proxy for a sub-range in a list of buffers.
+template <typename Buffer, typename Buffers, typename Buffer_Iterator>
+class consuming_buffers
+{
+public:
+  typedef prepared_buffers<Buffer, prepared_buffers_max<Buffers>::value>
+    prepared_buffers_type;
+
+  // Construct to represent the entire list of buffers.
+  explicit consuming_buffers(const Buffers& buffers)
+    : buffers_(buffers),
+      total_consumed_(0),
+      next_elem_(0),
+      next_elem_offset_(0)
+  {
+    using boost::asio::buffer_size;
+    total_size_ = buffer_size(buffers);
+  }
+
+  // Determine if we are at the end of the buffers.
+  bool empty() const
+  {
+    return total_consumed_ >= total_size_;
+  }
+
+  // Get the buffer for a single transfer, with a size.
+  prepared_buffers_type prepare(std::size_t max_size)
+  {
+    prepared_buffers_type result;
+
+    Buffer_Iterator next = boost::asio::buffer_sequence_begin(buffers_);
+    Buffer_Iterator end = boost::asio::buffer_sequence_end(buffers_);
+
+    std::advance(next, next_elem_);
+    std::size_t elem_offset = next_elem_offset_;
+    while (next != end && max_size > 0 && (result.count) < result.max_buffers)
+    {
+      Buffer next_buf = Buffer(*next) + elem_offset;
+      result.elems[result.count] = boost::asio::buffer(next_buf, max_size);
+      max_size -= result.elems[result.count].size();
+      elem_offset = 0;
+      if (result.elems[result.count].size() > 0)
+        ++result.count;
+      ++next;
+    }
+
+    return result;
+  }
+
+  // Consume the specified number of bytes from the buffers.
+  void consume(std::size_t size)
+  {
+    total_consumed_ += size;
+
+    Buffer_Iterator next = boost::asio::buffer_sequence_begin(buffers_);
+    Buffer_Iterator end = boost::asio::buffer_sequence_end(buffers_);
+
+    std::advance(next, next_elem_);
+    while (next != end && size > 0)
+    {
+      Buffer next_buf = Buffer(*next) + next_elem_offset_;
+      if (size < next_buf.size())
+      {
+        next_elem_offset_ += size;
+        size = 0;
+      }
+      else
+      {
+        size -= next_buf.size();
+        next_elem_offset_ = 0;
+        ++next_elem_;
+        ++next;
+      }
+    }
+  }
+
+  // Get the total number of bytes consumed from the buffers.
+  std::size_t total_consumed() const
+  {
+    return total_consumed_;
+  }
+
+private:
+  Buffers buffers_;
+  std::size_t total_size_;
+  std::size_t total_consumed_;
+  std::size_t next_elem_;
+  std::size_t next_elem_offset_;
+};
+
+// Base class of all consuming_buffers specialisations for single buffers.
+template <typename Buffer>
+class consuming_single_buffer
+{
+public:
+  // Construct to represent the entire list of buffers.
+  template <typename Buffer1>
+  explicit consuming_single_buffer(const Buffer1& buffer)
+    : buffer_(buffer),
+      total_consumed_(0)
+  {
+  }
+
+  // Determine if we are at the end of the buffers.
+  bool empty() const
+  {
+    return total_consumed_ >= buffer_.size();
+  }
+
+  // Get the buffer for a single transfer, with a size.
+  Buffer prepare(std::size_t max_size)
+  {
+    return boost::asio::buffer(buffer_ + total_consumed_, max_size);
+  }
+
+  // Consume the specified number of bytes from the buffers.
+  void consume(std::size_t size)
+  {
+    total_consumed_ += size;
+  }
+
+  // Get the total number of bytes consumed from the buffers.
+  std::size_t total_consumed() const
+  {
+    return total_consumed_;
+  }
+
+private:
+  Buffer buffer_;
+  std::size_t total_consumed_;
+};
+
+template <>
+class consuming_buffers<mutable_buffer, mutable_buffer, const mutable_buffer*>
+  : public consuming_single_buffer<BOOST_ASIO_MUTABLE_BUFFER>
+{
+public:
+  explicit consuming_buffers(const mutable_buffer& buffer)
+    : consuming_single_buffer<BOOST_ASIO_MUTABLE_BUFFER>(buffer)
+  {
+  }
+};
+
+template <>
+class consuming_buffers<const_buffer, mutable_buffer, const mutable_buffer*>
+  : public consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>
+{
+public:
+  explicit consuming_buffers(const mutable_buffer& buffer)
+    : consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>(buffer)
+  {
+  }
+};
+
+template <>
+class consuming_buffers<const_buffer, const_buffer, const const_buffer*>
+  : public consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>
+{
+public:
+  explicit consuming_buffers(const const_buffer& buffer)
+    : consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>(buffer)
+  {
+  }
+};
+
+#if !defined(BOOST_ASIO_NO_DEPRECATED)
+
+template <>
+class consuming_buffers<mutable_buffer,
+    mutable_buffers_1, const mutable_buffer*>
+  : public consuming_single_buffer<BOOST_ASIO_MUTABLE_BUFFER>
+{
+public:
+  explicit consuming_buffers(const mutable_buffers_1& buffer)
+    : consuming_single_buffer<BOOST_ASIO_MUTABLE_BUFFER>(buffer)
+  {
+  }
+};
+
+template <>
+class consuming_buffers<const_buffer, mutable_buffers_1, const mutable_buffer*>
+  : public consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>
+{
+public:
+  explicit consuming_buffers(const mutable_buffers_1& buffer)
+    : consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>(buffer)
+  {
+  }
+};
+
+template <>
+class consuming_buffers<const_buffer, const_buffers_1, const const_buffer*>
+  : public consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>
+{
+public:
+  explicit consuming_buffers(const const_buffers_1& buffer)
+    : consuming_single_buffer<BOOST_ASIO_CONST_BUFFER>(buffer)
+  {
+  }
+};
+
+#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
+
+template <typename Buffer, typename Elem>
+class consuming_buffers<Buffer, boost::array<Elem, 2>,
+    typename boost::array<Elem, 2>::const_iterator>
+{
+public:
+  // Construct to represent the entire list of buffers.
+  explicit consuming_buffers(const boost::array<Elem, 2>& buffers)
+    : buffers_(buffers),
+      total_consumed_(0)
+  {
+  }
+
+  // Determine if we are at the end of the buffers.
+  bool empty() const
+  {
+    return total_consumed_ >=
+      Buffer(buffers_[0]).size() + Buffer(buffers_[1]).size();
+  }
+
+  // Get the buffer for a single transfer, with a size.
+  boost::array<Buffer, 2> prepare(std::size_t max_size)
+  {
+    boost::array<Buffer, 2> result = {{
+      Buffer(buffers_[0]), Buffer(buffers_[1]) }};
+    std::size_t buffer0_size = result[0].size();
+    result[0] = boost::asio::buffer(result[0] + total_consumed_, max_size);
+    result[1] = boost::asio::buffer(
+        result[1] + (total_consumed_ < buffer0_size
+          ? 0 : total_consumed_ - buffer0_size),
+        max_size - result[0].size());
+    return result;
+  }
+
+  // Consume the specified number of bytes from the buffers.
+  void consume(std::size_t size)
+  {
+    total_consumed_ += size;
+  }
+
+  // Get the total number of bytes consumed from the buffers.
+  std::size_t total_consumed() const
+  {
+    return total_consumed_;
+  }
+
+private:
+  boost::array<Elem, 2> buffers_;
+  std::size_t total_consumed_;
+};
+
+#if defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+template <typename Buffer, typename Elem>
+class consuming_buffers<Buffer, std::array<Elem, 2>,
+    typename std::array<Elem, 2>::const_iterator>
+{
+public:
+  // Construct to represent the entire list of buffers.
+  explicit consuming_buffers(const std::array<Elem, 2>& buffers)
+    : buffers_(buffers),
+      total_consumed_(0)
+  {
+  }
+
+  // Determine if we are at the end of the buffers.
+  bool empty() const
+  {
+    return total_consumed_ >=
+      Buffer(buffers_[0]).size() + Buffer(buffers_[1]).size();
+  }
+
+  // Get the buffer for a single transfer, with a size.
+  std::array<Buffer, 2> prepare(std::size_t max_size)
+  {
+    std::array<Buffer, 2> result = {{
+      Buffer(buffers_[0]), Buffer(buffers_[1]) }};
+    std::size_t buffer0_size = result[0].size();
+    result[0] = boost::asio::buffer(result[0] + total_consumed_, max_size);
+    result[1] = boost::asio::buffer(
+        result[1] + (total_consumed_ < buffer0_size
+          ? 0 : total_consumed_ - buffer0_size),
+        max_size - result[0].size());
+    return result;
+  }
+
+  // Consume the specified number of bytes from the buffers.
+  void consume(std::size_t size)
+  {
+    total_consumed_ += size;
+  }
+
+  // Get the total number of bytes consumed from the buffers.
+  std::size_t total_consumed() const
+  {
+    return total_consumed_;
+  }
+
+private:
+  std::array<Elem, 2> buffers_;
+  std::size_t total_consumed_;
+};
+
+#endif // defined(BOOST_ASIO_HAS_STD_ARRAY)
+
+// Specialisation for null_buffers to ensure that the null_buffers type is
+// always passed through to the underlying read or write operation.
+template <typename Buffer>
+class consuming_buffers<Buffer, null_buffers, const mutable_buffer*>
+  : public boost::asio::null_buffers
+{
+public:
+  consuming_buffers(const null_buffers&)
+  {
+    // No-op.
+  }
+
+  bool empty()
+  {
+    return false;
+  }
+
+  null_buffers prepare(std::size_t)
+  {
+    return null_buffers();
+  }
+
+  void consume(std::size_t)
+  {
+    // No-op.
+  }
+
+  std::size_t total_consumed() const
+  {
+    return 0;
+  }
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_CONSUMING_BUFFERS_HPP

boost/asio/detail/cstddef.hpp

@@ -0,0 +1,33 @@
+//
+// detail/cstddef.hpp
+// ~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CSTDDEF_HPP
+#define BOOST_ASIO_DETAIL_CSTDDEF_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+
+namespace boost {
+namespace asio {
+
+#if defined(BOOST_ASIO_HAS_NULLPTR)
+using std::nullptr_t;
+#else // defined(BOOST_ASIO_HAS_NULLPTR)
+struct nullptr_t {};
+#endif // defined(BOOST_ASIO_HAS_NULLPTR)
+
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_CSTDDEF_HPP

boost/asio/detail/cstdint.hpp

@@ -0,0 +1,62 @@
+//
+// detail/cstdint.hpp
+// ~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_CSTDINT_HPP
+#define BOOST_ASIO_DETAIL_CSTDINT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_CSTDINT)
+# include <cstdint>
+#else // defined(BOOST_ASIO_HAS_CSTDINT)
+# include <boost/cstdint.hpp>
+#endif // defined(BOOST_ASIO_HAS_CSTDINT)
+
+namespace boost {
+namespace asio {
+
+#if defined(BOOST_ASIO_HAS_CSTDINT)
+using std::int16_t;
+using std::int_least16_t;
+using std::uint16_t;
+using std::uint_least16_t;
+using std::int32_t;
+using std::int_least32_t;
+using std::uint32_t;
+using std::uint_least32_t;
+using std::int64_t;
+using std::int_least64_t;
+using std::uint64_t;
+using std::uint_least64_t;
+using std::uintmax_t;
+#else // defined(BOOST_ASIO_HAS_CSTDINT)
+using boost::int16_t;
+using boost::int_least16_t;
+using boost::uint16_t;
+using boost::uint_least16_t;
+using boost::int32_t;
+using boost::int_least32_t;
+using boost::uint32_t;
+using boost::uint_least32_t;
+using boost::int64_t;
+using boost::int_least64_t;
+using boost::uint64_t;
+using boost::uint_least64_t;
+using boost::uintmax_t;
+#endif // defined(BOOST_ASIO_HAS_CSTDINT)
+
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_CSTDINT_HPP

boost/asio/detail/date_time_fwd.hpp

@@ -0,0 +1,34 @@
+//
+// detail/date_time_fwd.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_DATE_TIME_FWD_HPP
+#define BOOST_ASIO_DETAIL_DATE_TIME_FWD_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+namespace boost {
+namespace date_time {
+
+template<class T, class TimeSystem>
+class base_time;
+
+} // namespace date_time
+namespace posix_time {
+
+class ptime;
+
+} // namespace posix_time
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_DATE_TIME_FWD_HPP

boost/asio/detail/deadline_timer_service.hpp

@@ -0,0 +1,282 @@
+//
+// detail/deadline_timer_service.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
+#define BOOST_ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <cstddef>
+#include <boost/asio/error.hpp>
+#include <boost/asio/execution_context.hpp>
+#include <boost/asio/detail/bind_handler.hpp>
+#include <boost/asio/detail/fenced_block.hpp>
+#include <boost/asio/detail/memory.hpp>
+#include <boost/asio/detail/noncopyable.hpp>
+#include <boost/asio/detail/socket_ops.hpp>
+#include <boost/asio/detail/socket_types.hpp>
+#include <boost/asio/detail/timer_queue.hpp>
+#include <boost/asio/detail/timer_queue_ptime.hpp>
+#include <boost/asio/detail/timer_scheduler.hpp>
+#include <boost/asio/detail/wait_handler.hpp>
+#include <boost/asio/detail/wait_op.hpp>
+
+#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
+# include <chrono>
+# include <thread>
+#endif // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename Time_Traits>
+class deadline_timer_service
+  : public execution_context_service_base<deadline_timer_service<Time_Traits> >
+{
+public:
+  // The time type.
+  typedef typename Time_Traits::time_type time_type;
+
+  // The duration type.
+  typedef typename Time_Traits::duration_type duration_type;
+
+  // The implementation type of the timer. This type is dependent on the
+  // underlying implementation of the timer service.
+  struct implementation_type
+    : private boost::asio::detail::noncopyable
+  {
+    time_type expiry;
+    bool might_have_pending_waits;
+    typename timer_queue<Time_Traits>::per_timer_data timer_data;
+  };
+
+  // Constructor.
+  deadline_timer_service(execution_context& context)
+    : execution_context_service_base<
+        deadline_timer_service<Time_Traits> >(context),
+      scheduler_(boost::asio::use_service<timer_scheduler>(context))
+  {
+    scheduler_.init_task();
+    scheduler_.add_timer_queue(timer_queue_);
+  }
+
+  // Destructor.
+  ~deadline_timer_service()
+  {
+    scheduler_.remove_timer_queue(timer_queue_);
+  }
+
+  // Destroy all user-defined handler objects owned by the service.
+  void shutdown()
+  {
+  }
+
+  // Construct a new timer implementation.
+  void construct(implementation_type& impl)
+  {
+    impl.expiry = time_type();
+    impl.might_have_pending_waits = false;
+  }
+
+  // Destroy a timer implementation.
+  void destroy(implementation_type& impl)
+  {
+    boost::system::error_code ec;
+    cancel(impl, ec);
+  }
+
+  // Move-construct a new serial port implementation.
+  void move_construct(implementation_type& impl,
+      implementation_type& other_impl)
+  {
+    scheduler_.move_timer(timer_queue_, impl.timer_data, other_impl.timer_data);
+
+    impl.expiry = other_impl.expiry;
+    other_impl.expiry = time_type();
+
+    impl.might_have_pending_waits = other_impl.might_have_pending_waits;
+    other_impl.might_have_pending_waits = false;
+  }
+
+  // Move-assign from another serial port implementation.
+  void move_assign(implementation_type& impl,
+      deadline_timer_service& other_service,
+      implementation_type& other_impl)
+  {
+    if (this != &other_service)
+      if (impl.might_have_pending_waits)
+        scheduler_.cancel_timer(timer_queue_, impl.timer_data);
+
+    other_service.scheduler_.move_timer(other_service.timer_queue_,
+        impl.timer_data, other_impl.timer_data);
+
+    impl.expiry = other_impl.expiry;
+    other_impl.expiry = time_type();
+
+    impl.might_have_pending_waits = other_impl.might_have_pending_waits;
+    other_impl.might_have_pending_waits = false;
+  }
+
+  // Cancel any asynchronous wait operations associated with the timer.
+  std::size_t cancel(implementation_type& impl, boost::system::error_code& ec)
+  {
+    if (!impl.might_have_pending_waits)
+    {
+      ec = boost::system::error_code();
+      return 0;
+    }
+
+    BOOST_ASIO_HANDLER_OPERATION((scheduler_.context(),
+          "deadline_timer", &impl, 0, "cancel"));
+
+    std::size_t count = scheduler_.cancel_timer(timer_queue_, impl.timer_data);
+    impl.might_have_pending_waits = false;
+    ec = boost::system::error_code();
+    return count;
+  }
+
+  // Cancels one asynchronous wait operation associated with the timer.
+  std::size_t cancel_one(implementation_type& impl,
+      boost::system::error_code& ec)
+  {
+    if (!impl.might_have_pending_waits)
+    {
+      ec = boost::system::error_code();
+      return 0;
+    }
+
+    BOOST_ASIO_HANDLER_OPERATION((scheduler_.context(),
+          "deadline_timer", &impl, 0, "cancel_one"));
+
+    std::size_t count = scheduler_.cancel_timer(
+        timer_queue_, impl.timer_data, 1);
+    if (count == 0)
+      impl.might_have_pending_waits = false;
+    ec = boost::system::error_code();
+    return count;
+  }
+
+  // Get the expiry time for the timer as an absolute time.
+  time_type expiry(const implementation_type& impl) const
+  {
+    return impl.expiry;
+  }
+
+  // Get the expiry time for the timer as an absolute time.
+  time_type expires_at(const implementation_type& impl) const
+  {
+    return impl.expiry;
+  }
+
+  // Get the expiry time for the timer relative to now.
+  duration_type expires_from_now(const implementation_type& impl) const
+  {
+    return Time_Traits::subtract(this->expiry(impl), Time_Traits::now());
+  }
+
+  // Set the expiry time for the timer as an absolute time.
+  std::size_t expires_at(implementation_type& impl,
+      const time_type& expiry_time, boost::system::error_code& ec)
+  {
+    std::size_t count = cancel(impl, ec);
+    impl.expiry = expiry_time;
+    ec = boost::system::error_code();
+    return count;
+  }
+
+  // Set the expiry time for the timer relative to now.
+  std::size_t expires_after(implementation_type& impl,
+      const duration_type& expiry_time, boost::system::error_code& ec)
+  {
+    return expires_at(impl,
+        Time_Traits::add(Time_Traits::now(), expiry_time), ec);
+  }
+
+  // Set the expiry time for the timer relative to now.
+  std::size_t expires_from_now(implementation_type& impl,
+      const duration_type& expiry_time, boost::system::error_code& ec)
+  {
+    return expires_at(impl,
+        Time_Traits::add(Time_Traits::now(), expiry_time), ec);
+  }
+
+  // Perform a blocking wait on the timer.
+  void wait(implementation_type& impl, boost::system::error_code& ec)
+  {
+    time_type now = Time_Traits::now();
+    ec = boost::system::error_code();
+    while (Time_Traits::less_than(now, impl.expiry) && !ec)
+    {
+      this->do_wait(Time_Traits::to_posix_duration(
+            Time_Traits::subtract(impl.expiry, now)), ec);
+      now = Time_Traits::now();
+    }
+  }
+
+  // Start an asynchronous wait on the timer.
+  template <typename Handler, typename IoExecutor>
+  void async_wait(implementation_type& impl,
+      Handler& handler, const IoExecutor& io_ex)
+  {
+    // Allocate and construct an operation to wrap the handler.
+    typedef wait_handler<Handler, IoExecutor> op;
+    typename op::ptr p = { boost::asio::detail::addressof(handler),
+      op::ptr::allocate(handler), 0 };
+    p.p = new (p.v) op(handler, io_ex);
+
+    impl.might_have_pending_waits = true;
+
+    BOOST_ASIO_HANDLER_CREATION((scheduler_.context(),
+          *p.p, "deadline_timer", &impl, 0, "async_wait"));
+
+    scheduler_.schedule_timer(timer_queue_, impl.expiry, impl.timer_data, p.p);
+    p.v = p.p = 0;
+  }
+
+private:
+  // Helper function to wait given a duration type. The duration type should
+  // either be of type boost::posix_time::time_duration, or implement the
+  // required subset of its interface.
+  template <typename Duration>
+  void do_wait(const Duration& timeout, boost::system::error_code& ec)
+  {
+#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    std::this_thread::sleep_for(
+        std::chrono::seconds(timeout.total_seconds())
+        + std::chrono::microseconds(timeout.total_microseconds()));
+    ec = boost::system::error_code();
+#else // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+    ::timeval tv;
+    tv.tv_sec = timeout.total_seconds();
+    tv.tv_usec = timeout.total_microseconds() % 1000000;
+    socket_ops::select(0, 0, 0, 0, &tv, ec);
+#endif // defined(BOOST_ASIO_WINDOWS_RUNTIME)
+  }
+
+  // The queue of timers.
+  timer_queue<Time_Traits> timer_queue_;
+
+  // The object that schedules and executes timers. Usually a reactor.
+  timer_scheduler& scheduler_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP

boost/asio/detail/dependent_type.hpp

@@ -0,0 +1,38 @@
+//
+// detail/dependent_type.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_DEPENDENT_TYPE_HPP
+#define BOOST_ASIO_DETAIL_DEPENDENT_TYPE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename DependsOn, typename T>
+struct dependent_type
+{
+  typedef T type;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_DEPENDENT_TYPE_HPP

boost/asio/detail/descriptor_ops.hpp

@@ -0,0 +1,123 @@
+//
+// detail/descriptor_ops.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_DESCRIPTOR_OPS_HPP
+#define BOOST_ASIO_DETAIL_DESCRIPTOR_OPS_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_WINDOWS) \
+  && !defined(BOOST_ASIO_WINDOWS_RUNTIME) \
+  && !defined(__CYGWIN__)
+
+#include <cstddef>
+#include <boost/asio/error.hpp>
+#include <boost/system/error_code.hpp>
+#include <boost/asio/detail/socket_types.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+namespace descriptor_ops {
+
+// Descriptor state bits.
+enum
+{
+  // The user wants a non-blocking descriptor.
+  user_set_non_blocking = 1,
+
+  // The descriptor has been set non-blocking.
+  internal_non_blocking = 2,
+
+  // Helper "state" used to determine whether the descriptor is non-blocking.
+  non_blocking = user_set_non_blocking | internal_non_blocking,
+
+  // The descriptor may have been dup()-ed.
+  possible_dup = 4
+};
+
+typedef unsigned char state_type;
+
+template <typename ReturnType>
+inline ReturnType error_wrapper(ReturnType return_value,
+    boost::system::error_code& ec)
+{
+  ec = boost::system::error_code(errno,
+      boost::asio::error::get_system_category());
+  return return_value;
+}
+
+BOOST_ASIO_DECL int open(const char* path, int flags,
+    boost::system::error_code& ec);
+
+BOOST_ASIO_DECL int close(int d, state_type& state,
+    boost::system::error_code& ec);
+
+BOOST_ASIO_DECL bool set_user_non_blocking(int d,
+    state_type& state, bool value, boost::system::error_code& ec);
+
+BOOST_ASIO_DECL bool set_internal_non_blocking(int d,
+    state_type& state, bool value, boost::system::error_code& ec);
+
+typedef iovec buf;
+
+BOOST_ASIO_DECL std::size_t sync_read(int d, state_type state, buf* bufs,
+    std::size_t count, bool all_empty, boost::system::error_code& ec);
+
+BOOST_ASIO_DECL bool non_blocking_read(int d, buf* bufs, std::size_t count,
+    boost::system::error_code& ec, std::size_t& bytes_transferred);
+
+BOOST_ASIO_DECL std::size_t sync_write(int d, state_type state,
+    const buf* bufs, std::size_t count, bool all_empty,
+    boost::system::error_code& ec);
+
+BOOST_ASIO_DECL bool non_blocking_write(int d,
+    const buf* bufs, std::size_t count,
+    boost::system::error_code& ec, std::size_t& bytes_transferred);
+
+BOOST_ASIO_DECL int ioctl(int d, state_type& state, long cmd,
+    ioctl_arg_type* arg, boost::system::error_code& ec);
+
+BOOST_ASIO_DECL int fcntl(int d, int cmd, boost::system::error_code& ec);
+
+BOOST_ASIO_DECL int fcntl(int d, int cmd,
+    long arg, boost::system::error_code& ec);
+
+BOOST_ASIO_DECL int poll_read(int d,
+    state_type state, boost::system::error_code& ec);
+
+BOOST_ASIO_DECL int poll_write(int d,
+    state_type state, boost::system::error_code& ec);
+
+BOOST_ASIO_DECL int poll_error(int d,
+    state_type state, boost::system::error_code& ec);
+
+} // namespace descriptor_ops
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#if defined(BOOST_ASIO_HEADER_ONLY)
+# include <boost/asio/detail/impl/descriptor_ops.ipp>
+#endif // defined(BOOST_ASIO_HEADER_ONLY)
+
+#endif // !defined(BOOST_ASIO_WINDOWS)
+       //   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
+       //   && !defined(__CYGWIN__)
+
+#endif // BOOST_ASIO_DETAIL_DESCRIPTOR_OPS_HPP

boost/asio/detail/descriptor_read_op.hpp

@@ -0,0 +1,132 @@
+//
+// detail/descriptor_read_op.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_DESCRIPTOR_READ_OP_HPP
+#define BOOST_ASIO_DETAIL_DESCRIPTOR_READ_OP_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_WINDOWS) && !defined(__CYGWIN__)
+
+#include <boost/asio/detail/bind_handler.hpp>
+#include <boost/asio/detail/buffer_sequence_adapter.hpp>
+#include <boost/asio/detail/descriptor_ops.hpp>
+#include <boost/asio/detail/fenced_block.hpp>
+#include <boost/asio/detail/handler_work.hpp>
+#include <boost/asio/detail/memory.hpp>
+#include <boost/asio/detail/reactor_op.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename MutableBufferSequence>
+class descriptor_read_op_base : public reactor_op
+{
+public:
+  descriptor_read_op_base(int descriptor,
+      const MutableBufferSequence& buffers, func_type complete_func)
+    : reactor_op(&descriptor_read_op_base::do_perform, complete_func),
+      descriptor_(descriptor),
+      buffers_(buffers)
+  {
+  }
+
+  static status do_perform(reactor_op* base)
+  {
+    descriptor_read_op_base* o(static_cast<descriptor_read_op_base*>(base));
+
+    buffer_sequence_adapter<boost::asio::mutable_buffer,
+        MutableBufferSequence> bufs(o->buffers_);
+
+    status result = descriptor_ops::non_blocking_read(o->descriptor_,
+        bufs.buffers(), bufs.count(), o->ec_, o->bytes_transferred_)
+      ? done : not_done;
+
+    BOOST_ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_read",
+          o->ec_, o->bytes_transferred_));
+
+    return result;
+  }
+
+private:
+  int descriptor_;
+  MutableBufferSequence buffers_;
+};
+
+template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
+class descriptor_read_op
+  : public descriptor_read_op_base<MutableBufferSequence>
+{
+public:
+  BOOST_ASIO_DEFINE_HANDLER_PTR(descriptor_read_op);
+
+  descriptor_read_op(int descriptor, const MutableBufferSequence& buffers,
+      Handler& handler, const IoExecutor& io_ex)
+    : descriptor_read_op_base<MutableBufferSequence>(
+        descriptor, buffers, &descriptor_read_op::do_complete),
+      handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      io_executor_(io_ex)
+  {
+    handler_work<Handler, IoExecutor>::start(handler_, io_executor_);
+  }
+
+  static void do_complete(void* owner, operation* base,
+      const boost::system::error_code& /*ec*/,
+      std::size_t /*bytes_transferred*/)
+  {
+    // Take ownership of the handler object.
+    descriptor_read_op* o(static_cast<descriptor_read_op*>(base));
+    ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
+    handler_work<Handler, IoExecutor> w(o->handler_, o->io_executor_);
+
+    BOOST_ASIO_HANDLER_COMPLETION((*o));
+
+    // Make a copy of the handler so that the memory can be deallocated before
+    // the upcall is made. Even if we're not about to make an upcall, a
+    // sub-object of the handler may be the true owner of the memory associated
+    // with the handler. Consequently, a local copy of the handler is required
+    // to ensure that any owning sub-object remains valid until after we have
+    // deallocated the memory here.
+    detail::binder2<Handler, boost::system::error_code, std::size_t>
+      handler(o->handler_, o->ec_, o->bytes_transferred_);
+    p.h = boost::asio::detail::addressof(handler.handler_);
+    p.reset();
+
+    // Make the upcall if required.
+    if (owner)
+    {
+      fenced_block b(fenced_block::half);
+      BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
+      w.complete(handler, handler.handler_);
+      BOOST_ASIO_HANDLER_INVOCATION_END;
+    }
+  }
+
+private:
+  Handler handler_;
+  IoExecutor io_executor_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // !defined(BOOST_ASIO_WINDOWS) && !defined(__CYGWIN__)
+
+#endif // BOOST_ASIO_DETAIL_DESCRIPTOR_READ_OP_HPP

boost/asio/detail/descriptor_write_op.hpp

@@ -0,0 +1,132 @@
+//
+// detail/descriptor_write_op.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_DESCRIPTOR_WRITE_OP_HPP
+#define BOOST_ASIO_DETAIL_DESCRIPTOR_WRITE_OP_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_WINDOWS) && !defined(__CYGWIN__)
+
+#include <boost/asio/detail/bind_handler.hpp>
+#include <boost/asio/detail/buffer_sequence_adapter.hpp>
+#include <boost/asio/detail/descriptor_ops.hpp>
+#include <boost/asio/detail/fenced_block.hpp>
+#include <boost/asio/detail/handler_work.hpp>
+#include <boost/asio/detail/memory.hpp>
+#include <boost/asio/detail/reactor_op.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename ConstBufferSequence>
+class descriptor_write_op_base : public reactor_op
+{
+public:
+  descriptor_write_op_base(int descriptor,
+      const ConstBufferSequence& buffers, func_type complete_func)
+    : reactor_op(&descriptor_write_op_base::do_perform, complete_func),
+      descriptor_(descriptor),
+      buffers_(buffers)
+  {
+  }
+
+  static status do_perform(reactor_op* base)
+  {
+    descriptor_write_op_base* o(static_cast<descriptor_write_op_base*>(base));
+
+    buffer_sequence_adapter<boost::asio::const_buffer,
+        ConstBufferSequence> bufs(o->buffers_);
+
+    status result = descriptor_ops::non_blocking_write(o->descriptor_,
+        bufs.buffers(), bufs.count(), o->ec_, o->bytes_transferred_)
+      ? done : not_done;
+
+    BOOST_ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_write",
+          o->ec_, o->bytes_transferred_));
+
+    return result;
+  }
+
+private:
+  int descriptor_;
+  ConstBufferSequence buffers_;
+};
+
+template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
+class descriptor_write_op
+  : public descriptor_write_op_base<ConstBufferSequence>
+{
+public:
+  BOOST_ASIO_DEFINE_HANDLER_PTR(descriptor_write_op);
+
+  descriptor_write_op(int descriptor, const ConstBufferSequence& buffers,
+      Handler& handler, const IoExecutor& io_ex)
+    : descriptor_write_op_base<ConstBufferSequence>(
+        descriptor, buffers, &descriptor_write_op::do_complete),
+      handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
+      io_executor_(io_ex)
+  {
+    handler_work<Handler, IoExecutor>::start(handler_, io_executor_);
+  }
+
+  static void do_complete(void* owner, operation* base,
+      const boost::system::error_code& /*ec*/,
+      std::size_t /*bytes_transferred*/)
+  {
+    // Take ownership of the handler object.
+    descriptor_write_op* o(static_cast<descriptor_write_op*>(base));
+    ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
+    handler_work<Handler, IoExecutor> w(o->handler_, o->io_executor_);
+
+    BOOST_ASIO_HANDLER_COMPLETION((*o));
+
+    // Make a copy of the handler so that the memory can be deallocated before
+    // the upcall is made. Even if we're not about to make an upcall, a
+    // sub-object of the handler may be the true owner of the memory associated
+    // with the handler. Consequently, a local copy of the handler is required
+    // to ensure that any owning sub-object remains valid until after we have
+    // deallocated the memory here.
+    detail::binder2<Handler, boost::system::error_code, std::size_t>
+      handler(o->handler_, o->ec_, o->bytes_transferred_);
+    p.h = boost::asio::detail::addressof(handler.handler_);
+    p.reset();
+
+    // Make the upcall if required.
+    if (owner)
+    {
+      fenced_block b(fenced_block::half);
+      BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
+      w.complete(handler, handler.handler_);
+      BOOST_ASIO_HANDLER_INVOCATION_END;
+    }
+  }
+
+private:
+  Handler handler_;
+  IoExecutor io_executor_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // !defined(BOOST_ASIO_WINDOWS) && !defined(__CYGWIN__)
+
+#endif // BOOST_ASIO_DETAIL_DESCRIPTOR_WRITE_OP_HPP

boost/asio/detail/dev_poll_reactor.hpp

@@ -0,0 +1,220 @@
+//
+// detail/dev_poll_reactor.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_DEV_POLL_REACTOR_HPP
+#define BOOST_ASIO_DETAIL_DEV_POLL_REACTOR_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_DEV_POLL)
+
+#include <cstddef>
+#include <vector>
+#include <sys/devpoll.h>
+#include <boost/asio/detail/hash_map.hpp>
+#include <boost/asio/detail/limits.hpp>
+#include <boost/asio/detail/mutex.hpp>
+#include <boost/asio/detail/op_queue.hpp>
+#include <boost/asio/detail/reactor_op.hpp>
+#include <boost/asio/detail/reactor_op_queue.hpp>
+#include <boost/asio/detail/select_interrupter.hpp>
+#include <boost/asio/detail/socket_types.hpp>
+#include <boost/asio/detail/timer_queue_base.hpp>
+#include <boost/asio/detail/timer_queue_set.hpp>
+#include <boost/asio/detail/wait_op.hpp>
+#include <boost/asio/execution_context.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class dev_poll_reactor
+  : public execution_context_service_base<dev_poll_reactor>
+{
+public:
+  enum op_types { read_op = 0, write_op = 1,
+    connect_op = 1, except_op = 2, max_ops = 3 };
+
+  // Per-descriptor data.
+  struct per_descriptor_data
+  {
+  };
+
+  // Constructor.
+  BOOST_ASIO_DECL dev_poll_reactor(boost::asio::execution_context& ctx);
+
+  // Destructor.
+  BOOST_ASIO_DECL ~dev_poll_reactor();
+
+  // Destroy all user-defined handler objects owned by the service.
+  BOOST_ASIO_DECL void shutdown();
+
+  // Recreate internal descriptors following a fork.
+  BOOST_ASIO_DECL void notify_fork(
+      boost::asio::execution_context::fork_event fork_ev);
+
+  // Initialise the task.
+  BOOST_ASIO_DECL void init_task();
+
+  // Register a socket with the reactor. Returns 0 on success, system error
+  // code on failure.
+  BOOST_ASIO_DECL int register_descriptor(socket_type, per_descriptor_data&);
+
+  // Register a descriptor with an associated single operation. Returns 0 on
+  // success, system error code on failure.
+  BOOST_ASIO_DECL int register_internal_descriptor(
+      int op_type, socket_type descriptor,
+      per_descriptor_data& descriptor_data, reactor_op* op);
+
+  // Move descriptor registration from one descriptor_data object to another.
+  BOOST_ASIO_DECL void move_descriptor(socket_type descriptor,
+      per_descriptor_data& target_descriptor_data,
+      per_descriptor_data& source_descriptor_data);
+
+  // Post a reactor operation for immediate completion.
+  void post_immediate_completion(reactor_op* op, bool is_continuation)
+  {
+    scheduler_.post_immediate_completion(op, is_continuation);
+  }
+
+  // Start a new operation. The reactor operation will be performed when the
+  // given descriptor is flagged as ready, or an error has occurred.
+  BOOST_ASIO_DECL void start_op(int op_type, socket_type descriptor,
+      per_descriptor_data&, reactor_op* op,
+      bool is_continuation, bool allow_speculative);
+
+  // Cancel all operations associated with the given descriptor. The
+  // handlers associated with the descriptor will be invoked with the
+  // operation_aborted error.
+  BOOST_ASIO_DECL void cancel_ops(socket_type descriptor, per_descriptor_data&);
+
+  // Cancel any operations that are running against the descriptor and remove
+  // its registration from the reactor. The reactor resources associated with
+  // the descriptor must be released by calling cleanup_descriptor_data.
+  BOOST_ASIO_DECL void deregister_descriptor(socket_type descriptor,
+      per_descriptor_data&, bool closing);
+
+  // Remove the descriptor's registration from the reactor. The reactor
+  // resources associated with the descriptor must be released by calling
+  // cleanup_descriptor_data.
+  BOOST_ASIO_DECL void deregister_internal_descriptor(
+      socket_type descriptor, per_descriptor_data&);
+
+  // Perform any post-deregistration cleanup tasks associated with the
+  // descriptor data.
+  BOOST_ASIO_DECL void cleanup_descriptor_data(per_descriptor_data&);
+
+  // Add a new timer queue to the reactor.
+  template <typename Time_Traits>
+  void add_timer_queue(timer_queue<Time_Traits>& queue);
+
+  // Remove a timer queue from the reactor.
+  template <typename Time_Traits>
+  void remove_timer_queue(timer_queue<Time_Traits>& queue);
+
+  // Schedule a new operation in the given timer queue to expire at the
+  // specified absolute time.
+  template <typename Time_Traits>
+  void schedule_timer(timer_queue<Time_Traits>& queue,
+      const typename Time_Traits::time_type& time,
+      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
+
+  // Cancel the timer operations associated with the given token. Returns the
+  // number of operations that have been posted or dispatched.
+  template <typename Time_Traits>
+  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
+      typename timer_queue<Time_Traits>::per_timer_data& timer,
+      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
+
+  // Move the timer operations associated with the given timer.
+  template <typename Time_Traits>
+  void move_timer(timer_queue<Time_Traits>& queue,
+      typename timer_queue<Time_Traits>::per_timer_data& target,
+      typename timer_queue<Time_Traits>::per_timer_data& source);
+
+  // Run /dev/poll once until interrupted or events are ready to be dispatched.
+  BOOST_ASIO_DECL void run(long usec, op_queue<operation>& ops);
+
+  // Interrupt the select loop.
+  BOOST_ASIO_DECL void interrupt();
+
+private:
+  // Create the /dev/poll file descriptor. Throws an exception if the descriptor
+  // cannot be created.
+  BOOST_ASIO_DECL static int do_dev_poll_create();
+
+  // Helper function to add a new timer queue.
+  BOOST_ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
+
+  // Helper function to remove a timer queue.
+  BOOST_ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
+
+  // Get the timeout value for the /dev/poll DP_POLL operation. The timeout
+  // value is returned as a number of milliseconds. A return value of -1
+  // indicates that the poll should block indefinitely.
+  BOOST_ASIO_DECL int get_timeout(int msec);
+
+  // Cancel all operations associated with the given descriptor. The do_cancel
+  // function of the handler objects will be invoked. This function does not
+  // acquire the dev_poll_reactor's mutex.
+  BOOST_ASIO_DECL void cancel_ops_unlocked(socket_type descriptor,
+      const boost::system::error_code& ec);
+
+  // Add a pending event entry for the given descriptor.
+  BOOST_ASIO_DECL ::pollfd& add_pending_event_change(int descriptor);
+
+  // The scheduler implementation used to post completions.
+  scheduler& scheduler_;
+
+  // Mutex to protect access to internal data.
+  boost::asio::detail::mutex mutex_;
+
+  // The /dev/poll file descriptor.
+  int dev_poll_fd_;
+
+  // Vector of /dev/poll events waiting to be written to the descriptor.
+  std::vector< ::pollfd> pending_event_changes_;
+
+  // Hash map to associate a descriptor with a pending event change index.
+  hash_map<int, std::size_t> pending_event_change_index_;
+
+  // The interrupter is used to break a blocking DP_POLL operation.
+  select_interrupter interrupter_;
+
+  // The queues of read, write and except operations.
+  reactor_op_queue<socket_type> op_queue_[max_ops];
+
+  // The timer queues.
+  timer_queue_set timer_queues_;
+
+  // Whether the service has been shut down.
+  bool shutdown_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/detail/impl/dev_poll_reactor.hpp>
+#if defined(BOOST_ASIO_HEADER_ONLY)
+# include <boost/asio/detail/impl/dev_poll_reactor.ipp>
+#endif // defined(BOOST_ASIO_HEADER_ONLY)
+
+#endif // defined(BOOST_ASIO_HAS_DEV_POLL)
+
+#endif // BOOST_ASIO_DETAIL_DEV_POLL_REACTOR_HPP

boost/asio/detail/epoll_reactor.hpp

@@ -0,0 +1,268 @@
+//
+// detail/epoll_reactor.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_EPOLL_REACTOR_HPP
+#define BOOST_ASIO_DETAIL_EPOLL_REACTOR_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_EPOLL)
+
+#include <boost/asio/detail/atomic_count.hpp>
+#include <boost/asio/detail/conditionally_enabled_mutex.hpp>
+#include <boost/asio/detail/limits.hpp>
+#include <boost/asio/detail/object_pool.hpp>
+#include <boost/asio/detail/op_queue.hpp>
+#include <boost/asio/detail/reactor_op.hpp>
+#include <boost/asio/detail/select_interrupter.hpp>
+#include <boost/asio/detail/socket_types.hpp>
+#include <boost/asio/detail/timer_queue_base.hpp>
+#include <boost/asio/detail/timer_queue_set.hpp>
+#include <boost/asio/detail/wait_op.hpp>
+#include <boost/asio/execution_context.hpp>
+
+#if defined(BOOST_ASIO_HAS_TIMERFD)
+# include <sys/timerfd.h>
+#endif // defined(BOOST_ASIO_HAS_TIMERFD)
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class epoll_reactor
+  : public execution_context_service_base<epoll_reactor>
+{
+private:
+  // The mutex type used by this reactor.
+  typedef conditionally_enabled_mutex mutex;
+
+public:
+  enum op_types { read_op = 0, write_op = 1,
+    connect_op = 1, except_op = 2, max_ops = 3 };
+
+  // Per-descriptor queues.
+  class descriptor_state : operation
+  {
+    friend class epoll_reactor;
+    friend class object_pool_access;
+
+    descriptor_state* next_;
+    descriptor_state* prev_;
+
+    mutex mutex_;
+    epoll_reactor* reactor_;
+    int descriptor_;
+    uint32_t registered_events_;
+    op_queue<reactor_op> op_queue_[max_ops];
+    bool try_speculative_[max_ops];
+    bool shutdown_;
+
+    BOOST_ASIO_DECL descriptor_state(bool locking);
+    void set_ready_events(uint32_t events) { task_result_ = events; }
+    void add_ready_events(uint32_t events) { task_result_ |= events; }
+    BOOST_ASIO_DECL operation* perform_io(uint32_t events);
+    BOOST_ASIO_DECL static void do_complete(
+        void* owner, operation* base,
+        const boost::system::error_code& ec, std::size_t bytes_transferred);
+  };
+
+  // Per-descriptor data.
+  typedef descriptor_state* per_descriptor_data;
+
+  // Constructor.
+  BOOST_ASIO_DECL epoll_reactor(boost::asio::execution_context& ctx);
+
+  // Destructor.
+  BOOST_ASIO_DECL ~epoll_reactor();
+
+  // Destroy all user-defined handler objects owned by the service.
+  BOOST_ASIO_DECL void shutdown();
+
+  // Recreate internal descriptors following a fork.
+  BOOST_ASIO_DECL void notify_fork(
+      boost::asio::execution_context::fork_event fork_ev);
+
+  // Initialise the task.
+  BOOST_ASIO_DECL void init_task();
+
+  // Register a socket with the reactor. Returns 0 on success, system error
+  // code on failure.
+  BOOST_ASIO_DECL int register_descriptor(socket_type descriptor,
+      per_descriptor_data& descriptor_data);
+
+  // Register a descriptor with an associated single operation. Returns 0 on
+  // success, system error code on failure.
+  BOOST_ASIO_DECL int register_internal_descriptor(
+      int op_type, socket_type descriptor,
+      per_descriptor_data& descriptor_data, reactor_op* op);
+
+  // Move descriptor registration from one descriptor_data object to another.
+  BOOST_ASIO_DECL void move_descriptor(socket_type descriptor,
+      per_descriptor_data& target_descriptor_data,
+      per_descriptor_data& source_descriptor_data);
+
+  // Post a reactor operation for immediate completion.
+  void post_immediate_completion(reactor_op* op, bool is_continuation)
+  {
+    scheduler_.post_immediate_completion(op, is_continuation);
+  }
+
+  // Start a new operation. The reactor operation will be performed when the
+  // given descriptor is flagged as ready, or an error has occurred.
+  BOOST_ASIO_DECL void start_op(int op_type, socket_type descriptor,
+      per_descriptor_data& descriptor_data, reactor_op* op,
+      bool is_continuation, bool allow_speculative);
+
+  // Cancel all operations associated with the given descriptor. The
+  // handlers associated with the descriptor will be invoked with the
+  // operation_aborted error.
+  BOOST_ASIO_DECL void cancel_ops(socket_type descriptor,
+      per_descriptor_data& descriptor_data);
+
+  // Cancel any operations that are running against the descriptor and remove
+  // its registration from the reactor. The reactor resources associated with
+  // the descriptor must be released by calling cleanup_descriptor_data.
+  BOOST_ASIO_DECL void deregister_descriptor(socket_type descriptor,
+      per_descriptor_data& descriptor_data, bool closing);
+
+  // Remove the descriptor's registration from the reactor. The reactor
+  // resources associated with the descriptor must be released by calling
+  // cleanup_descriptor_data.
+  BOOST_ASIO_DECL void deregister_internal_descriptor(
+      socket_type descriptor, per_descriptor_data& descriptor_data);
+
+  // Perform any post-deregistration cleanup tasks associated with the
+  // descriptor data.
+  BOOST_ASIO_DECL void cleanup_descriptor_data(
+      per_descriptor_data& descriptor_data);
+
+  // Add a new timer queue to the reactor.
+  template <typename Time_Traits>
+  void add_timer_queue(timer_queue<Time_Traits>& timer_queue);
+
+  // Remove a timer queue from the reactor.
+  template <typename Time_Traits>
+  void remove_timer_queue(timer_queue<Time_Traits>& timer_queue);
+
+  // Schedule a new operation in the given timer queue to expire at the
+  // specified absolute time.
+  template <typename Time_Traits>
+  void schedule_timer(timer_queue<Time_Traits>& queue,
+      const typename Time_Traits::time_type& time,
+      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
+
+  // Cancel the timer operations associated with the given token. Returns the
+  // number of operations that have been posted or dispatched.
+  template <typename Time_Traits>
+  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
+      typename timer_queue<Time_Traits>::per_timer_data& timer,
+      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
+
+  // Move the timer operations associated with the given timer.
+  template <typename Time_Traits>
+  void move_timer(timer_queue<Time_Traits>& queue,
+      typename timer_queue<Time_Traits>::per_timer_data& target,
+      typename timer_queue<Time_Traits>::per_timer_data& source);
+
+  // Run epoll once until interrupted or events are ready to be dispatched.
+  BOOST_ASIO_DECL void run(long usec, op_queue<operation>& ops);
+
+  // Interrupt the select loop.
+  BOOST_ASIO_DECL void interrupt();
+
+private:
+  // The hint to pass to epoll_create to size its data structures.
+  enum { epoll_size = 20000 };
+
+  // Create the epoll file descriptor. Throws an exception if the descriptor
+  // cannot be created.
+  BOOST_ASIO_DECL static int do_epoll_create();
+
+  // Create the timerfd file descriptor. Does not throw.
+  BOOST_ASIO_DECL static int do_timerfd_create();
+
+  // Allocate a new descriptor state object.
+  BOOST_ASIO_DECL descriptor_state* allocate_descriptor_state();
+
+  // Free an existing descriptor state object.
+  BOOST_ASIO_DECL void free_descriptor_state(descriptor_state* s);
+
+  // Helper function to add a new timer queue.
+  BOOST_ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
+
+  // Helper function to remove a timer queue.
+  BOOST_ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
+
+  // Called to recalculate and update the timeout.
+  BOOST_ASIO_DECL void update_timeout();
+
+  // Get the timeout value for the epoll_wait call. The timeout value is
+  // returned as a number of milliseconds. A return value of -1 indicates
+  // that epoll_wait should block indefinitely.
+  BOOST_ASIO_DECL int get_timeout(int msec);
+
+#if defined(BOOST_ASIO_HAS_TIMERFD)
+  // Get the timeout value for the timer descriptor. The return value is the
+  // flag argument to be used when calling timerfd_settime.
+  BOOST_ASIO_DECL int get_timeout(itimerspec& ts);
+#endif // defined(BOOST_ASIO_HAS_TIMERFD)
+
+  // The scheduler implementation used to post completions.
+  scheduler& scheduler_;
+
+  // Mutex to protect access to internal data.
+  mutex mutex_;
+
+  // The interrupter is used to break a blocking epoll_wait call.
+  select_interrupter interrupter_;
+
+  // The epoll file descriptor.
+  int epoll_fd_;
+
+  // The timer file descriptor.
+  int timer_fd_;
+
+  // The timer queues.
+  timer_queue_set timer_queues_;
+
+  // Whether the service has been shut down.
+  bool shutdown_;
+
+  // Mutex to protect access to the registered descriptors.
+  mutex registered_descriptors_mutex_;
+
+  // Keep track of all registered descriptors.
+  object_pool<descriptor_state> registered_descriptors_;
+
+  // Helper class to do post-perform_io cleanup.
+  struct perform_io_cleanup_on_block_exit;
+  friend struct perform_io_cleanup_on_block_exit;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/detail/impl/epoll_reactor.hpp>
+#if defined(BOOST_ASIO_HEADER_ONLY)
+# include <boost/asio/detail/impl/epoll_reactor.ipp>
+#endif // defined(BOOST_ASIO_HEADER_ONLY)
+
+#endif // defined(BOOST_ASIO_HAS_EPOLL)
+
+#endif // BOOST_ASIO_DETAIL_EPOLL_REACTOR_HPP

boost/asio/detail/event.hpp

@@ -0,0 +1,50 @@
+//
+// detail/event.hpp
+// ~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_EVENT_HPP
+#define BOOST_ASIO_DETAIL_EVENT_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_HAS_THREADS)
+# include <boost/asio/detail/null_event.hpp>
+#elif defined(BOOST_ASIO_WINDOWS)
+# include <boost/asio/detail/win_event.hpp>
+#elif defined(BOOST_ASIO_HAS_PTHREADS)
+# include <boost/asio/detail/posix_event.hpp>
+#elif defined(BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR)
+# include <boost/asio/detail/std_event.hpp>
+#else
+# error Only Windows, POSIX and std::condition_variable are supported!
+#endif
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+#if !defined(BOOST_ASIO_HAS_THREADS)
+typedef null_event event;
+#elif defined(BOOST_ASIO_WINDOWS)
+typedef win_event event;
+#elif defined(BOOST_ASIO_HAS_PTHREADS)
+typedef posix_event event;
+#elif defined(BOOST_ASIO_HAS_STD_MUTEX_AND_CONDVAR)
+typedef std_event event;
+#endif
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_EVENT_HPP

boost/asio/detail/eventfd_select_interrupter.hpp

@@ -0,0 +1,85 @@
+//
+// detail/eventfd_select_interrupter.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+// Copyright (c) 2008 Roelof Naude (roelof.naude at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP
+#define BOOST_ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_EVENTFD)
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class eventfd_select_interrupter
+{
+public:
+  // Constructor.
+  BOOST_ASIO_DECL eventfd_select_interrupter();
+
+  // Destructor.
+  BOOST_ASIO_DECL ~eventfd_select_interrupter();
+
+  // Recreate the interrupter's descriptors. Used after a fork.
+  BOOST_ASIO_DECL void recreate();
+
+  // Interrupt the select call.
+  BOOST_ASIO_DECL void interrupt();
+
+  // Reset the select interrupt. Returns true if the call was interrupted.
+  BOOST_ASIO_DECL bool reset();
+
+  // Get the read descriptor to be passed to select.
+  int read_descriptor() const
+  {
+    return read_descriptor_;
+  }
+
+private:
+  // Open the descriptors. Throws on error.
+  BOOST_ASIO_DECL void open_descriptors();
+
+  // Close the descriptors.
+  BOOST_ASIO_DECL void close_descriptors();
+
+  // The read end of a connection used to interrupt the select call. This file
+  // descriptor is passed to select such that when it is time to stop, a single
+  // 64bit value will be written on the other end of the connection and this
+  // descriptor will become readable.
+  int read_descriptor_;
+
+  // The write end of a connection used to interrupt the select call. A single
+  // 64bit non-zero value may be written to this to wake up the select which is
+  // waiting for the other end to become readable. This descriptor will only
+  // differ from the read descriptor when a pipe is used.
+  int write_descriptor_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#if defined(BOOST_ASIO_HEADER_ONLY)
+# include <boost/asio/detail/impl/eventfd_select_interrupter.ipp>
+#endif // defined(BOOST_ASIO_HEADER_ONLY)
+
+#endif // defined(BOOST_ASIO_HAS_EVENTFD)
+
+#endif // BOOST_ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP

boost/asio/detail/executor_function.hpp

@@ -0,0 +1,106 @@
+//
+// detail/executor_function.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_EXECUTOR_FUNCTION_HPP
+#define BOOST_ASIO_DETAIL_EXECUTOR_FUNCTION_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/handler_alloc_helpers.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class executor_function_base
+{
+public:
+  void complete()
+  {
+    func_(this, true);
+  }
+
+  void destroy()
+  {
+    func_(this, false);
+  }
+
+protected:
+  typedef void (*func_type)(executor_function_base*, bool);
+
+  executor_function_base(func_type func)
+    : func_(func)
+  {
+  }
+
+  // Prevents deletion through this type.
+  ~executor_function_base()
+  {
+  }
+
+private:
+  func_type func_;
+};
+
+template <typename Function, typename Alloc>
+class executor_function : public executor_function_base
+{
+public:
+  BOOST_ASIO_DEFINE_TAGGED_HANDLER_ALLOCATOR_PTR(
+      thread_info_base::executor_function_tag, executor_function);
+
+  template <typename F>
+  executor_function(BOOST_ASIO_MOVE_ARG(F) f, const Alloc& allocator)
+    : executor_function_base(&executor_function::do_complete),
+      function_(BOOST_ASIO_MOVE_CAST(F)(f)),
+      allocator_(allocator)
+  {
+  }
+
+  static void do_complete(executor_function_base* base, bool call)
+  {
+    // Take ownership of the function object.
+    executor_function* o(static_cast<executor_function*>(base));
+    Alloc allocator(o->allocator_);
+    ptr p = { detail::addressof(allocator), o, o };
+
+    // Make a copy of the function so that the memory can be deallocated before
+    // the upcall is made. Even if we're not about to make an upcall, a
+    // sub-object of the function may be the true owner of the memory
+    // associated with the function. Consequently, a local copy of the function
+    // is required to ensure that any owning sub-object remains valid until
+    // after we have deallocated the memory here.
+    Function function(BOOST_ASIO_MOVE_CAST(Function)(o->function_));
+    p.reset();
+
+    // Make the upcall if required.
+    if (call)
+    {
+      function();
+    }
+  }
+
+private:
+  Function function_;
+  Alloc allocator_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_EXECUTOR_FUNCTION_HPP

boost/asio/detail/executor_op.hpp

@@ -0,0 +1,86 @@
+//
+// detail/executor_op.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_EXECUTOR_OP_HPP
+#define BOOST_ASIO_DETAIL_EXECUTOR_OP_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/fenced_block.hpp>
+#include <boost/asio/detail/handler_alloc_helpers.hpp>
+#include <boost/asio/detail/handler_invoke_helpers.hpp>
+#include <boost/asio/detail/scheduler_operation.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename Handler, typename Alloc,
+    typename Operation = scheduler_operation>
+class executor_op : public Operation
+{
+public:
+  BOOST_ASIO_DEFINE_HANDLER_ALLOCATOR_PTR(executor_op);
+
+  template <typename H>
+  executor_op(BOOST_ASIO_MOVE_ARG(H) h, const Alloc& allocator)
+    : Operation(&executor_op::do_complete),
+      handler_(BOOST_ASIO_MOVE_CAST(H)(h)),
+      allocator_(allocator)
+  {
+  }
+
+  static void do_complete(void* owner, Operation* base,
+      const boost::system::error_code& /*ec*/,
+      std::size_t /*bytes_transferred*/)
+  {
+    // Take ownership of the handler object.
+    executor_op* o(static_cast<executor_op*>(base));
+    Alloc allocator(o->allocator_);
+    ptr p = { detail::addressof(allocator), o, o };
+
+    BOOST_ASIO_HANDLER_COMPLETION((*o));
+
+    // Make a copy of the handler so that the memory can be deallocated before
+    // the upcall is made. Even if we're not about to make an upcall, a
+    // sub-object of the handler may be the true owner of the memory associated
+    // with the handler. Consequently, a local copy of the handler is required
+    // to ensure that any owning sub-object remains valid until after we have
+    // deallocated the memory here.
+    Handler handler(BOOST_ASIO_MOVE_CAST(Handler)(o->handler_));
+    p.reset();
+
+    // Make the upcall if required.
+    if (owner)
+    {
+      fenced_block b(fenced_block::half);
+      BOOST_ASIO_HANDLER_INVOCATION_BEGIN(());
+      boost_asio_handler_invoke_helpers::invoke(handler, handler);
+      BOOST_ASIO_HANDLER_INVOCATION_END;
+    }
+  }
+
+private:
+  Handler handler_;
+  Alloc allocator_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_EXECUTOR_OP_HPP

boost/asio/detail/fd_set_adapter.hpp

@@ -0,0 +1,41 @@
+//
+// detail/fd_set_adapter.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_FD_SET_ADAPTER_HPP
+#define BOOST_ASIO_DETAIL_FD_SET_ADAPTER_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_WINDOWS_RUNTIME)
+
+#include <boost/asio/detail/posix_fd_set_adapter.hpp>
+#include <boost/asio/detail/win_fd_set_adapter.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+#if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
+typedef win_fd_set_adapter fd_set_adapter;
+#else
+typedef posix_fd_set_adapter fd_set_adapter;
+#endif
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#endif // !defined(BOOST_ASIO_WINDOWS_RUNTIME)
+
+#endif // BOOST_ASIO_DETAIL_FD_SET_ADAPTER_HPP

boost/asio/detail/fenced_block.hpp

@@ -0,0 +1,82 @@
+//
+// detail/fenced_block.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_FENCED_BLOCK_HPP
+#define BOOST_ASIO_DETAIL_FENCED_BLOCK_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if !defined(BOOST_ASIO_HAS_THREADS) \
+  || defined(BOOST_ASIO_DISABLE_FENCED_BLOCK)
+# include <boost/asio/detail/null_fenced_block.hpp>
+#elif defined(BOOST_ASIO_HAS_STD_ATOMIC)
+# include <boost/asio/detail/std_fenced_block.hpp>
+#elif defined(__MACH__) && defined(__APPLE__)
+# include <boost/asio/detail/macos_fenced_block.hpp>
+#elif defined(__sun)
+# include <boost/asio/detail/solaris_fenced_block.hpp>
+#elif defined(__GNUC__) && defined(__arm__) \
+  && !defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
+# include <boost/asio/detail/gcc_arm_fenced_block.hpp>
+#elif defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
+# include <boost/asio/detail/gcc_hppa_fenced_block.hpp>
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+# include <boost/asio/detail/gcc_x86_fenced_block.hpp>
+#elif defined(__GNUC__) \
+  && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)) \
+  && !defined(__INTEL_COMPILER) && !defined(__ICL) \
+  && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
+# include <boost/asio/detail/gcc_sync_fenced_block.hpp>
+#elif defined(BOOST_ASIO_WINDOWS) && !defined(UNDER_CE)
+# include <boost/asio/detail/win_fenced_block.hpp>
+#else
+# include <boost/asio/detail/null_fenced_block.hpp>
+#endif
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+#if !defined(BOOST_ASIO_HAS_THREADS) \
+  || defined(BOOST_ASIO_DISABLE_FENCED_BLOCK)
+typedef null_fenced_block fenced_block;
+#elif defined(BOOST_ASIO_HAS_STD_ATOMIC)
+typedef std_fenced_block fenced_block;
+#elif defined(__MACH__) && defined(__APPLE__)
+typedef macos_fenced_block fenced_block;
+#elif defined(__sun)
+typedef solaris_fenced_block fenced_block;
+#elif defined(__GNUC__) && defined(__arm__) \
+  && !defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
+typedef gcc_arm_fenced_block fenced_block;
+#elif defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
+typedef gcc_hppa_fenced_block fenced_block;
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+typedef gcc_x86_fenced_block fenced_block;
+#elif defined(__GNUC__) \
+  && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)) \
+  && !defined(__INTEL_COMPILER) && !defined(__ICL) \
+  && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
+typedef gcc_sync_fenced_block fenced_block;
+#elif defined(BOOST_ASIO_WINDOWS) && !defined(UNDER_CE)
+typedef win_fenced_block fenced_block;
+#else
+typedef null_fenced_block fenced_block;
+#endif
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_FENCED_BLOCK_HPP

boost/asio/detail/functional.hpp

@@ -0,0 +1,40 @@
+//
+// detail/functional.hpp
+// ~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_FUNCTIONAL_HPP
+#define BOOST_ASIO_DETAIL_FUNCTIONAL_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#include <functional>
+
+#if !defined(BOOST_ASIO_HAS_STD_FUNCTION)
+# include <boost/function.hpp>
+#endif // !defined(BOOST_ASIO_HAS_STD_FUNCTION)
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+#if defined(BOOST_ASIO_HAS_STD_FUNCTION)
+using std::function;
+#else // defined(BOOST_ASIO_HAS_STD_FUNCTION)
+using boost::function;
+#endif // defined(BOOST_ASIO_HAS_STD_FUNCTION)
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#endif // BOOST_ASIO_DETAIL_FUNCTIONAL_HPP

boost/asio/detail/future.hpp

@@ -0,0 +1,33 @@
+//
+// detail/future.hpp
+// ~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_FUTURE_HPP
+#define BOOST_ASIO_DETAIL_FUTURE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#if defined(BOOST_ASIO_HAS_STD_FUTURE)
+# include <future>
+// Even though the future header is available, libstdc++ may not implement the
+// std::future class itself. However, we need to have already included the
+// future header to reliably test for _GLIBCXX_HAS_GTHREADS.
+# if defined(__GNUC__) && !defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
+#  if defined(_GLIBCXX_HAS_GTHREADS)
+#   define BOOST_ASIO_HAS_STD_FUTURE_CLASS 1
+#  endif // defined(_GLIBCXX_HAS_GTHREADS)
+# else // defined(__GNUC__) && !defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
+#  define BOOST_ASIO_HAS_STD_FUTURE_CLASS 1
+# endif // defined(__GNUC__) && !defined(BOOST_ASIO_HAS_CLANG_LIBCXX)
+#endif // defined(BOOST_ASIO_HAS_STD_FUTURE)
+
+#endif // BOOST_ASIO_DETAIL_FUTURE_HPP

boost/asio/detail/gcc_arm_fenced_block.hpp

@@ -0,0 +1,93 @@
+//
+// detail/gcc_arm_fenced_block.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_GCC_ARM_FENCED_BLOCK_HPP
+#define BOOST_ASIO_DETAIL_GCC_ARM_FENCED_BLOCK_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(__GNUC__) && defined(__arm__)
+
+#include <boost/asio/detail/noncopyable.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class gcc_arm_fenced_block
+  : private noncopyable
+{
+public:
+  enum half_t { half };
+  enum full_t { full };
+
+  // Constructor for a half fenced block.
+  explicit gcc_arm_fenced_block(half_t)
+  {
+  }
+
+  // Constructor for a full fenced block.
+  explicit gcc_arm_fenced_block(full_t)
+  {
+    barrier();
+  }
+
+  // Destructor.
+  ~gcc_arm_fenced_block()
+  {
+    barrier();
+  }
+
+private:
+  static void barrier()
+  {
+#if defined(__ARM_ARCH_4__) \
+    || defined(__ARM_ARCH_4T__) \
+    || defined(__ARM_ARCH_5__) \
+    || defined(__ARM_ARCH_5E__) \
+    || defined(__ARM_ARCH_5T__) \
+    || defined(__ARM_ARCH_5TE__) \
+    || defined(__ARM_ARCH_5TEJ__) \
+    || defined(__ARM_ARCH_6__) \
+    || defined(__ARM_ARCH_6J__) \
+    || defined(__ARM_ARCH_6K__) \
+    || defined(__ARM_ARCH_6Z__) \
+    || defined(__ARM_ARCH_6ZK__) \
+    || defined(__ARM_ARCH_6T2__)
+# if defined(__thumb__)
+    // This is just a placeholder and almost certainly not sufficient.
+    __asm__ __volatile__ ("" : : : "memory");
+# else // defined(__thumb__)
+    int a = 0, b = 0;
+    __asm__ __volatile__ ("swp %0, %1, [%2]"
+        : "=&r"(a) : "r"(1), "r"(&b) : "memory", "cc");
+# endif // defined(__thumb__)
+#else
+    // ARMv7 and later.
+    __asm__ __volatile__ ("dmb" : : : "memory");
+#endif
+  }
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(__GNUC__) && defined(__arm__)
+
+#endif // BOOST_ASIO_DETAIL_GCC_ARM_FENCED_BLOCK_HPP

boost/asio/detail/gcc_hppa_fenced_block.hpp

@@ -0,0 +1,70 @@
+//
+// detail/gcc_hppa_fenced_block.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_GCC_HPPA_FENCED_BLOCK_HPP
+#define BOOST_ASIO_DETAIL_GCC_HPPA_FENCED_BLOCK_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
+
+#include <boost/asio/detail/noncopyable.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class gcc_hppa_fenced_block
+  : private noncopyable
+{
+public:
+  enum half_t { half };
+  enum full_t { full };
+
+  // Constructor for a half fenced block.
+  explicit gcc_hppa_fenced_block(half_t)
+  {
+  }
+
+  // Constructor for a full fenced block.
+  explicit gcc_hppa_fenced_block(full_t)
+  {
+    barrier();
+  }
+
+  // Destructor.
+  ~gcc_hppa_fenced_block()
+  {
+    barrier();
+  }
+
+private:
+  static void barrier()
+  {
+    // This is just a placeholder and almost certainly not sufficient.
+    __asm__ __volatile__ ("" : : : "memory");
+  }
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
+
+#endif // BOOST_ASIO_DETAIL_GCC_HPPA_FENCED_BLOCK_HPP

boost/asio/detail/gcc_sync_fenced_block.hpp

@@ -0,0 +1,67 @@
+//
+// detail/gcc_sync_fenced_block.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_HPP
+#define BOOST_ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(__GNUC__) \
+  && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)) \
+  && !defined(__INTEL_COMPILER) && !defined(__ICL) \
+  && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
+
+#include <boost/asio/detail/noncopyable.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class gcc_sync_fenced_block
+  : private noncopyable
+{
+public:
+  enum half_or_full_t { half, full };
+
+  // Constructor.
+  explicit gcc_sync_fenced_block(half_or_full_t)
+    : value_(0)
+  {
+    __sync_lock_test_and_set(&value_, 1);
+  }
+
+  // Destructor.
+  ~gcc_sync_fenced_block()
+  {
+    __sync_lock_release(&value_);
+  }
+
+private:
+  int value_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(__GNUC__)
+       // && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4))
+       // && !defined(__INTEL_COMPILER) && !defined(__ICL)
+       // && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
+
+#endif // BOOST_ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_HPP

boost/asio/detail/gcc_x86_fenced_block.hpp

@@ -0,0 +1,101 @@
+//
+// detail/gcc_x86_fenced_block.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP
+#define BOOST_ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+
+#include <boost/asio/detail/noncopyable.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class gcc_x86_fenced_block
+  : private noncopyable
+{
+public:
+  enum half_t { half };
+  enum full_t { full };
+
+  // Constructor for a half fenced block.
+  explicit gcc_x86_fenced_block(half_t)
+  {
+  }
+
+  // Constructor for a full fenced block.
+  explicit gcc_x86_fenced_block(full_t)
+  {
+    lbarrier();
+  }
+
+  // Destructor.
+  ~gcc_x86_fenced_block()
+  {
+    sbarrier();
+  }
+
+private:
+  static int barrier()
+  {
+    int r = 0, m = 1;
+    __asm__ __volatile__ (
+        "xchgl %0, %1" :
+        "=r"(r), "=m"(m) :
+        "0"(1), "m"(m) :
+        "memory", "cc");
+    return r;
+  }
+
+  static void lbarrier()
+  {
+#if defined(__SSE2__)
+# if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
+    __builtin_ia32_lfence();
+# else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
+    __asm__ __volatile__ ("lfence" ::: "memory");
+# endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
+#else // defined(__SSE2__)
+    barrier();
+#endif // defined(__SSE2__)
+  }
+
+  static void sbarrier()
+  {
+#if defined(__SSE2__)
+# if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
+    __builtin_ia32_sfence();
+# else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
+    __asm__ __volatile__ ("sfence" ::: "memory");
+# endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
+#else // defined(__SSE2__)
+    barrier();
+#endif // defined(__SSE2__)
+  }
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+
+#endif // BOOST_ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP