ext-boost/boost/smart_ptr/detail/local_counted_base.hpp
2019-08-24 15:39:04 +02:00

149 lines
3.1 KiB
C++

#ifndef BOOST_SMART_PTR_DETAIL_LOCAL_COUNTED_BASE_HPP_INCLUDED
#define BOOST_SMART_PTR_DETAIL_LOCAL_COUNTED_BASE_HPP_INCLUDED
// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
// detail/local_counted_base.hpp
//
// Copyright 2017 Peter Dimov
//
// 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/libs/smart_ptr/ for documentation.
#include <boost/smart_ptr/detail/shared_count.hpp>
#include <boost/config.hpp>
#include <utility>
namespace boost
{
namespace detail
{
class BOOST_SYMBOL_VISIBLE local_counted_base
{
private:
local_counted_base & operator= ( local_counted_base const & );
private:
// not 'int' or 'unsigned' to avoid aliasing and enable optimizations
enum count_type { min_ = 0, initial_ = 1, max_ = 2147483647 };
count_type local_use_count_;
public:
BOOST_CONSTEXPR local_counted_base() BOOST_SP_NOEXCEPT: local_use_count_( initial_ )
{
}
BOOST_CONSTEXPR local_counted_base( local_counted_base const & ) BOOST_SP_NOEXCEPT: local_use_count_( initial_ )
{
}
virtual ~local_counted_base() /*BOOST_SP_NOEXCEPT*/
{
}
virtual void local_cb_destroy() BOOST_SP_NOEXCEPT = 0;
virtual boost::detail::shared_count local_cb_get_shared_count() const BOOST_SP_NOEXCEPT = 0;
void add_ref() BOOST_SP_NOEXCEPT
{
#if !defined(__NVCC__)
#if defined( __has_builtin )
# if __has_builtin( __builtin_assume )
__builtin_assume( local_use_count_ >= 1 );
# endif
#endif
#endif
local_use_count_ = static_cast<count_type>( local_use_count_ + 1 );
}
void release() BOOST_SP_NOEXCEPT
{
local_use_count_ = static_cast<count_type>( local_use_count_ - 1 );
if( local_use_count_ == 0 )
{
local_cb_destroy();
}
}
long local_use_count() const BOOST_SP_NOEXCEPT
{
return local_use_count_;
}
};
class BOOST_SYMBOL_VISIBLE local_counted_impl: public local_counted_base
{
private:
local_counted_impl( local_counted_impl const & );
private:
shared_count pn_;
public:
explicit local_counted_impl( shared_count const& pn ) BOOST_SP_NOEXCEPT: pn_( pn )
{
}
#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
explicit local_counted_impl( shared_count && pn ) BOOST_SP_NOEXCEPT: pn_( std::move(pn) )
{
}
#endif
virtual void local_cb_destroy() BOOST_SP_NOEXCEPT
{
delete this;
}
virtual boost::detail::shared_count local_cb_get_shared_count() const BOOST_SP_NOEXCEPT
{
return pn_;
}
};
class BOOST_SYMBOL_VISIBLE local_counted_impl_em: public local_counted_base
{
public:
shared_count pn_;
virtual void local_cb_destroy() BOOST_SP_NOEXCEPT
{
shared_count().swap( pn_ );
}
virtual boost::detail::shared_count local_cb_get_shared_count() const BOOST_SP_NOEXCEPT
{
return pn_;
}
};
} // namespace detail
} // namespace boost
#endif // #ifndef BOOST_SMART_PTR_DETAIL_LOCAL_COUNTED_BASE_HPP_INCLUDED