| /* |
| * 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) |
| * |
| * Copyright (c) 2009 Helge Bahmann |
| * Copyright (c) 2012 Tim Blechmann |
| * Copyright (c) 2013 - 2014 Andrey Semashev |
| */ |
| /*! |
| * \file atomic/detail/casts.hpp |
| * |
| * This header defines \c union_cast and \c memcpy_cast used to convert between storage and value types |
| */ |
| |
| #ifndef BOOST_ATOMIC_DETAIL_CASTS_HPP_INCLUDED_ |
| #define BOOST_ATOMIC_DETAIL_CASTS_HPP_INCLUDED_ |
| |
| #include <cstring> |
| #include <boost/atomic/detail/config.hpp> |
| |
| #ifdef BOOST_HAS_PRAGMA_ONCE |
| #pragma once |
| #endif |
| |
| namespace boost { |
| namespace atomics { |
| namespace detail { |
| |
| template< typename To, typename From > |
| BOOST_FORCEINLINE To union_cast(From const& from) BOOST_NOEXCEPT |
| { |
| union |
| { |
| To as_to; |
| From as_from; |
| } |
| caster = {}; |
| caster.as_from = from; |
| return caster.as_to; |
| } |
| |
| template< typename To, typename From > |
| BOOST_FORCEINLINE To memcpy_cast(From const& from) BOOST_NOEXCEPT |
| { |
| struct |
| { |
| To to; |
| } |
| value = {}; |
| std::memcpy |
| ( |
| &reinterpret_cast< char& >(value.to), |
| &reinterpret_cast< const char& >(from), |
| (sizeof(From) < sizeof(To) ? sizeof(From) : sizeof(To)) |
| ); |
| return value.to; |
| } |
| |
| } // namespace detail |
| } // namespace atomics |
| } // namespace boost |
| |
| #endif // BOOST_ATOMIC_DETAIL_CASTS_HPP_INCLUDED_ |