#ifndef BOOST_THREAD_PTHREAD_ONCE_HPP #define BOOST_THREAD_PTHREAD_ONCE_HPP // once.hpp // // (C) Copyright 2007-8 Anthony Williams // (C) Copyright 2011-2012 Vicente J. Botet Escriba // // 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) #include #include #include #include #include #include #include #include #include #include #include #include namespace boost { struct once_flag; #define BOOST_ONCE_INITIAL_FLAG_VALUE 0 namespace thread_detail { typedef boost::uint32_t uintmax_atomic_t; #define BOOST_THREAD_DETAIL_UINTMAX_ATOMIC_C2(value) value##u #define BOOST_THREAD_DETAIL_UINTMAX_ATOMIC_MAX_C BOOST_THREAD_DETAIL_UINTMAX_ATOMIC_C2(~0) } #ifdef BOOST_THREAD_PROVIDES_ONCE_CXX11 #ifndef BOOST_NO_CXX11_VARIADIC_TEMPLATES template inline void call_once(once_flag& flag, BOOST_THREAD_RV_REF(Function) f, BOOST_THREAD_RV_REF(ArgTypes)... args); #else template inline void call_once(once_flag& flag, Function f); template inline void call_once(once_flag& flag, Function f, T1 p1); template inline void call_once(once_flag& flag, Function f, T1 p1, T2 p2); template inline void call_once(once_flag& flag, Function f, T1 p1, T2 p2, T3 p3); #endif struct once_flag { BOOST_THREAD_NO_COPYABLE(once_flag) BOOST_CONSTEXPR once_flag() BOOST_NOEXCEPT : epoch(BOOST_ONCE_INITIAL_FLAG_VALUE) {} private: volatile thread_detail::uintmax_atomic_t epoch; #ifndef BOOST_NO_CXX11_VARIADIC_TEMPLATES template friend void call_once(once_flag& flag, BOOST_THREAD_RV_REF(Function) f, BOOST_THREAD_RV_REF(ArgTypes)... args); #else template friend void call_once(once_flag& flag, Function f); template friend void call_once(once_flag& flag, Function f, T1 p1); template friend void call_once(once_flag& flag, Function f, T1 p1, T2 p2); template friend void call_once(once_flag& flag, Function f, T1 p1, T2 p2, T3 p3); #endif }; #define BOOST_ONCE_INIT once_flag() #else // BOOST_THREAD_PROVIDES_ONCE_CXX11 struct once_flag { volatile thread_detail::uintmax_atomic_t epoch; }; #define BOOST_ONCE_INIT {BOOST_ONCE_INITIAL_FLAG_VALUE} #endif // BOOST_THREAD_PROVIDES_ONCE_CXX11 #if defined BOOST_THREAD_PROVIDES_INVOKE #define BOOST_THREAD_INVOKE_RET_VOID detail::invoke #define BOOST_THREAD_INVOKE_RET_VOID_CALL #elif defined BOOST_THREAD_PROVIDES_INVOKE_RET #define BOOST_THREAD_INVOKE_RET_VOID detail::invoke #define BOOST_THREAD_INVOKE_RET_VOID_CALL #else #define BOOST_THREAD_INVOKE_RET_VOID boost::bind #define BOOST_THREAD_INVOKE_RET_VOID_CALL () #endif namespace thread_detail { BOOST_THREAD_DECL uintmax_atomic_t& get_once_per_thread_epoch(); BOOST_THREAD_DECL extern uintmax_atomic_t once_global_epoch; BOOST_THREAD_DECL extern pthread_mutex_t once_epoch_mutex; BOOST_THREAD_DECL extern pthread_cond_t once_epoch_cv; } // Based on Mike Burrows fast_pthread_once algorithm as described in // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2444.html #ifndef BOOST_NO_CXX11_VARIADIC_TEMPLATES template inline void call_once(once_flag& flag, BOOST_THREAD_RV_REF(Function) f, BOOST_THREAD_RV_REF(ArgTypes)... args) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch(f)), thread_detail::decay_copy(boost::forward(args))... ) BOOST_THREAD_INVOKE_RET_VOID_CALL; } BOOST_CATCH (...) { flag.epoch=uninitialized_flag; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); BOOST_RETHROW } BOOST_CATCH_END flag.epoch=--thread_detail::once_global_epoch; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); } else { while(flag.epoch==being_initialized) { BOOST_VERIFY(!pthread_cond_wait(&thread_detail::once_epoch_cv,&thread_detail::once_epoch_mutex)); } } } this_thread_epoch=thread_detail::once_global_epoch; } } #else template inline void call_once(once_flag& flag, Function f) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch inline void call_once(once_flag& flag, Function f, T1 p1) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch inline void call_once(once_flag& flag, Function f, T1 p1, T2 p2) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch inline void call_once(once_flag& flag, Function f, T1 p1, T2 p2, T3 p3) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch inline void call_once(once_flag& flag, BOOST_THREAD_RV_REF(Function) f) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch inline void call_once(once_flag& flag, BOOST_THREAD_RV_REF(Function) f, BOOST_THREAD_RV_REF(T1) p1) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch(f)), thread_detail::decay_copy(boost::forward(p1)) ) BOOST_THREAD_INVOKE_RET_VOID_CALL; } BOOST_CATCH (...) { flag.epoch=uninitialized_flag; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); BOOST_RETHROW } BOOST_CATCH_END flag.epoch=--thread_detail::once_global_epoch; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); } else { while(flag.epoch==being_initialized) { BOOST_VERIFY(!pthread_cond_wait(&thread_detail::once_epoch_cv,&thread_detail::once_epoch_mutex)); } } } this_thread_epoch=thread_detail::once_global_epoch; } } template inline void call_once(once_flag& flag, BOOST_THREAD_RV_REF(Function) f, BOOST_THREAD_RV_REF(T1) p1, BOOST_THREAD_RV_REF(T2) p2) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch(f)), thread_detail::decay_copy(boost::forward(p1)), thread_detail::decay_copy(boost::forward(p2)) ) BOOST_THREAD_INVOKE_RET_VOID_CALL; } BOOST_CATCH (...) { flag.epoch=uninitialized_flag; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); BOOST_RETHROW } BOOST_CATCH_END flag.epoch=--thread_detail::once_global_epoch; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); } else { while(flag.epoch==being_initialized) { BOOST_VERIFY(!pthread_cond_wait(&thread_detail::once_epoch_cv,&thread_detail::once_epoch_mutex)); } } } this_thread_epoch=thread_detail::once_global_epoch; } } template inline void call_once(once_flag& flag, BOOST_THREAD_RV_REF(Function) f, BOOST_THREAD_RV_REF(T1) p1, BOOST_THREAD_RV_REF(T2) p2, BOOST_THREAD_RV_REF(T3) p3) { static thread_detail::uintmax_atomic_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static thread_detail::uintmax_atomic_t const being_initialized=uninitialized_flag+1; thread_detail::uintmax_atomic_t const epoch=flag.epoch; thread_detail::uintmax_atomic_t& this_thread_epoch=thread_detail::get_once_per_thread_epoch(); if(epoch(f)), thread_detail::decay_copy(boost::forward(p1)), thread_detail::decay_copy(boost::forward(p2)), thread_detail::decay_copy(boost::forward(p3)) ) BOOST_THREAD_INVOKE_RET_VOID_CALL; } BOOST_CATCH (...) { flag.epoch=uninitialized_flag; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); BOOST_RETHROW } BOOST_CATCH_END flag.epoch=--thread_detail::once_global_epoch; BOOST_VERIFY(!pthread_cond_broadcast(&thread_detail::once_epoch_cv)); } else { while(flag.epoch==being_initialized) { BOOST_VERIFY(!pthread_cond_wait(&thread_detail::once_epoch_cv,&thread_detail::once_epoch_mutex)); } } } this_thread_epoch=thread_detail::once_global_epoch; } } #endif } #include #endif