atomic/detail/once_flag.hpp

0001 /*
0002  * Distributed under the Boost Software License, Version 1.0.
0003  * (See accompanying file LICENSE_1_0.txt or copy at
0004  * http://www.boost.org/LICENSE_1_0.txt)
0005  *
0006  * Copyright (c) 2020 Andrey Semashev
0007  */
0008 /*!
0009  * \file   atomic/detail/once_flag.hpp
0010  *
0011  * This header declares \c once_flag structure for controlling one time initialization
0012  */
0013
0014 #ifndef BOOST_ATOMIC_DETAIL_ONCE_FLAG_HPP_INCLUDED_
0015 #define BOOST_ATOMIC_DETAIL_ONCE_FLAG_HPP_INCLUDED_
0016
0017 #include <boost/atomic/detail/config.hpp>
0018 #include <boost/atomic/detail/aligned_variable.hpp>
0019 #include <boost/atomic/detail/core_operations.hpp>
0020 #include <boost/atomic/detail/header.hpp>
0021
0022 #ifdef BOOST_HAS_PRAGMA_ONCE
0023 #pragma once
0024 #endif
0025
0026 namespace boost {
0027 namespace atomics {
0028 namespace detail {
0029
0030 typedef atomics::detail::core_operations< 1u, false, false > once_flag_operations;
0031
0032 struct once_flag
0033 {
0034     BOOST_ATOMIC_DETAIL_ALIGNED_VAR(once_flag_operations::storage_alignment, once_flag_operations::storage_type, m_flag);
0035 };
0036
0037 } // namespace detail
0038 } // namespace atomics
0039 } // namespace boost
0040
0041 #include <boost/atomic/detail/footer.hpp>
0042
0043 #endif // BOOST_ATOMIC_DETAIL_ONCE_FLAG_HPP_INCLUDED_