ext-boost/boost/asio/windows/basic_object_handle.hpp
2019-08-24 15:39:04 +02:00

399 lines
13 KiB
C++

//
// windows/basic_object_handle.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
// Copyright (c) 2011 Boris Schaeling (boris@highscore.de)
//
// 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_WINDOWS_BASIC_OBJECT_HANDLE_HPP
#define BOOST_ASIO_WINDOWS_BASIC_OBJECT_HANDLE_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_WINDOWS_OBJECT_HANDLE) \
|| defined(GENERATING_DOCUMENTATION)
#include <boost/asio/async_result.hpp>
#include <boost/asio/detail/io_object_impl.hpp>
#include <boost/asio/detail/throw_error.hpp>
#include <boost/asio/detail/win_object_handle_service.hpp>
#include <boost/asio/error.hpp>
#include <boost/asio/execution_context.hpp>
#include <boost/asio/executor.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 {
namespace windows {
/// Provides object-oriented handle functionality.
/**
* The windows::basic_object_handle class provides asynchronous and blocking
* object-oriented handle functionality.
*
* @par Thread Safety
* @e Distinct @e objects: Safe.@n
* @e Shared @e objects: Unsafe.
*/
template <typename Executor = executor>
class basic_object_handle
{
public:
/// The type of the executor associated with the object.
typedef Executor executor_type;
/// The native representation of a handle.
#if defined(GENERATING_DOCUMENTATION)
typedef implementation_defined native_handle_type;
#else
typedef boost::asio::detail::win_object_handle_service::native_handle_type
native_handle_type;
#endif
/// An object handle is always the lowest layer.
typedef basic_object_handle lowest_layer_type;
/// Construct an object handle without opening it.
/**
* This constructor creates an object handle without opening it.
*
* @param ex The I/O executor that the object handle will use, by default, to
* dispatch handlers for any asynchronous operations performed on the
* object handle.
*/
explicit basic_object_handle(const executor_type& ex)
: impl_(ex)
{
}
/// Construct an object handle without opening it.
/**
* This constructor creates an object handle without opening it.
*
* @param context An execution context which provides the I/O executor that
* the object handle will use, by default, to dispatch handlers for any
* asynchronous operations performed on the object handle.
*/
template <typename ExecutionContext>
explicit basic_object_handle(ExecutionContext& context,
typename enable_if<
is_convertible<ExecutionContext&, execution_context&>::value,
basic_object_handle
>::type* = 0)
: impl_(context)
{
}
/// Construct an object handle on an existing native handle.
/**
* This constructor creates an object handle object to hold an existing native
* handle.
*
* @param ex The I/O executor that the object handle will use, by default, to
* dispatch handlers for any asynchronous operations performed on the
* object handle.
*
* @param native_handle The new underlying handle implementation.
*
* @throws boost::system::system_error Thrown on failure.
*/
basic_object_handle(const executor_type& ex,
const native_handle_type& native_handle)
: impl_(ex)
{
boost::system::error_code ec;
impl_.get_service().assign(impl_.get_implementation(), native_handle, ec);
boost::asio::detail::throw_error(ec, "assign");
}
/// Construct an object handle on an existing native handle.
/**
* This constructor creates an object handle object to hold an existing native
* handle.
*
* @param context An execution context which provides the I/O executor that
* the object handle will use, by default, to dispatch handlers for any
* asynchronous operations performed on the object handle.
*
* @param native_handle The new underlying handle implementation.
*
* @throws boost::system::system_error Thrown on failure.
*/
template <typename ExecutionContext>
basic_object_handle(ExecutionContext& context,
const native_handle_type& native_handle,
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_handle, ec);
boost::asio::detail::throw_error(ec, "assign");
}
#if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
/// Move-construct an object handle from another.
/**
* This constructor moves an object handle from one object to another.
*
* @param other The other object handle 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_object_handle(const executor_type&)
* constructor.
*/
basic_object_handle(basic_object_handle&& other)
: impl_(std::move(other.impl_))
{
}
/// Move-assign an object handle from another.
/**
* This assignment operator moves an object handle from one object to another.
*
* @param other The other object handle 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_object_handle(const executor_type&)
* constructor.
*/
basic_object_handle& operator=(basic_object_handle&& other)
{
impl_ = std::move(other.impl_);
return *this;
}
#endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
/// 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 an object handle 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 an object handle 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;
}
/// Assign an existing native handle to the handle.
/*
* This function opens the handle to hold an existing native handle.
*
* @param handle A native handle.
*
* @throws boost::system::system_error Thrown on failure.
*/
void assign(const native_handle_type& handle)
{
boost::system::error_code ec;
impl_.get_service().assign(impl_.get_implementation(), handle, ec);
boost::asio::detail::throw_error(ec, "assign");
}
/// Assign an existing native handle to the handle.
/*
* This function opens the handle to hold an existing native handle.
*
* @param handle A native handle.
*
* @param ec Set to indicate what error occurred, if any.
*/
BOOST_ASIO_SYNC_OP_VOID assign(const native_handle_type& handle,
boost::system::error_code& ec)
{
impl_.get_service().assign(impl_.get_implementation(), handle, ec);
BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
}
/// Determine whether the handle is open.
bool is_open() const
{
return impl_.get_service().is_open(impl_.get_implementation());
}
/// Close the handle.
/**
* This function is used to close the handle. 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 handle.
/**
* This function is used to close the handle. 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 handle representation.
/**
* This function may be used to obtain the underlying representation of the
* handle. This is intended to allow access to native handle 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 handle.
/**
* 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 handle.
/**
* 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);
}
/// Perform a blocking wait on the object handle.
/**
* This function is used to wait for the object handle to be set to the
* signalled state. This function blocks and does not return until the object
* handle has been set to the signalled state.
*
* @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 object handle.
/**
* This function is used to wait for the object handle to be set to the
* signalled state. This function blocks and does not return until the object
* handle has been set to the signalled state.
*
* @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 object handle.
/**
* This function is be used to initiate an asynchronous wait against the
* object handle. It always returns immediately.
*
* @param handler The handler to be called when the object handle is set to
* the signalled state. 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)
{
boost::asio::async_completion<WaitHandler,
void (boost::system::error_code)> init(handler);
impl_.get_service().async_wait(impl_.get_implementation(),
init.completion_handler, impl_.get_implementation_executor());
return init.result.get();
}
private:
// Disallow copying and assignment.
basic_object_handle(const basic_object_handle&) BOOST_ASIO_DELETED;
basic_object_handle& operator=(const basic_object_handle&) BOOST_ASIO_DELETED;
boost::asio::detail::io_object_impl<
boost::asio::detail::win_object_handle_service, Executor> impl_;
};
} // namespace windows
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#endif // defined(BOOST_ASIO_HAS_WINDOWS_OBJECT_HANDLE)
// || defined(GENERATING_DOCUMENTATION)
#endif // BOOST_ASIO_WINDOWS_BASIC_OBJECT_HANDLE_HPP