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Diffstat (limited to 'libstdc++-v3/include/ext/concurrence.h')
| -rw-r--r-- | libstdc++-v3/include/ext/concurrence.h | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/libstdc++-v3/include/ext/concurrence.h b/libstdc++-v3/include/ext/concurrence.h new file mode 100644 index 000000000..ce999e5e3 --- /dev/null +++ b/libstdc++-v3/include/ext/concurrence.h @@ -0,0 +1,401 @@ +// Support for concurrent programing -*- C++ -*- + +// Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 +// Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// Under Section 7 of GPL version 3, you are granted additional +// permissions described in the GCC Runtime Library Exception, version +// 3.1, as published by the Free Software Foundation. + +// You should have received a copy of the GNU General Public License and +// a copy of the GCC Runtime Library Exception along with this program; +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +// <http://www.gnu.org/licenses/>. + +/** @file ext/concurrence.h + * This file is a GNU extension to the Standard C++ Library. + */ + +#ifndef _CONCURRENCE_H +#define _CONCURRENCE_H 1 + +#pragma GCC system_header + +#include <exception> +#include <bits/gthr.h> +#include <bits/functexcept.h> +#include <bits/cpp_type_traits.h> +#include <ext/type_traits.h> + +namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) +{ +_GLIBCXX_BEGIN_NAMESPACE_VERSION + + // Available locking policies: + // _S_single single-threaded code that doesn't need to be locked. + // _S_mutex multi-threaded code that requires additional support + // from gthr.h or abstraction layers in concurrence.h. + // _S_atomic multi-threaded code using atomic operations. + enum _Lock_policy { _S_single, _S_mutex, _S_atomic }; + + // Compile time constant that indicates prefered locking policy in + // the current configuration. + static const _Lock_policy __default_lock_policy = +#ifdef __GTHREADS +#if (defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_2) \ + && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)) + _S_atomic; +#else + _S_mutex; +#endif +#else + _S_single; +#endif + + // NB: As this is used in libsupc++, need to only depend on + // exception. No stdexception classes, no use of std::string. + class __concurrence_lock_error : public std::exception + { + public: + virtual char const* + what() const throw() + { return "__gnu_cxx::__concurrence_lock_error"; } + }; + + class __concurrence_unlock_error : public std::exception + { + public: + virtual char const* + what() const throw() + { return "__gnu_cxx::__concurrence_unlock_error"; } + }; + + class __concurrence_broadcast_error : public std::exception + { + public: + virtual char const* + what() const throw() + { return "__gnu_cxx::__concurrence_broadcast_error"; } + }; + + class __concurrence_wait_error : public std::exception + { + public: + virtual char const* + what() const throw() + { return "__gnu_cxx::__concurrence_wait_error"; } + }; + + // Substitute for concurrence_error object in the case of -fno-exceptions. + inline void + __throw_concurrence_lock_error() + { +#if __EXCEPTIONS + throw __concurrence_lock_error(); +#else + __builtin_abort(); +#endif + } + + inline void + __throw_concurrence_unlock_error() + { +#if __EXCEPTIONS + throw __concurrence_unlock_error(); +#else + __builtin_abort(); +#endif + } + +#ifdef __GTHREAD_HAS_COND + inline void + __throw_concurrence_broadcast_error() + { +#if __EXCEPTIONS + throw __concurrence_broadcast_error(); +#else + __builtin_abort(); +#endif + } + + inline void + __throw_concurrence_wait_error() + { +#if __EXCEPTIONS + throw __concurrence_wait_error(); +#else + __builtin_abort(); +#endif + } +#endif + + template<typename _Tp> + static inline void + __copy_gthr_type(_Tp& __to, const _Tp& __from) + { +#if defined __GXX_EXPERIMENTAL_CXX0X__ \ + && defined _GLIBCXX_GTHREADS_NO_COPY_ASSIGN_IN_CXX11 + __builtin_memcpy(&__to, &__from, sizeof(__to)); +#else + __to = __from; +#endif + } + + class __mutex + { + private: + __gthread_mutex_t _M_mutex; + + __mutex(const __mutex&); + __mutex& operator=(const __mutex&); + + public: + __mutex() + { +#if __GTHREADS + if (__gthread_active_p()) + { +#if defined __GTHREAD_MUTEX_INIT + __gthread_mutex_t __tmp = __GTHREAD_MUTEX_INIT; + __copy_gthr_type(_M_mutex, __tmp); +#else + __GTHREAD_MUTEX_INIT_FUNCTION(&_M_mutex); +#endif + } +#endif + } + +#if __GTHREADS && ! defined __GTHREAD_MUTEX_INIT + ~__mutex() + { + if (__gthread_active_p()) + __gthread_mutex_destroy(&_M_mutex); + } +#endif + + void lock() + { +#if __GTHREADS + if (__gthread_active_p()) + { + if (__gthread_mutex_lock(&_M_mutex) != 0) + __throw_concurrence_lock_error(); + } +#endif + } + + void unlock() + { +#if __GTHREADS + if (__gthread_active_p()) + { + if (__gthread_mutex_unlock(&_M_mutex) != 0) + __throw_concurrence_unlock_error(); + } +#endif + } + + __gthread_mutex_t* gthread_mutex(void) + { return &_M_mutex; } + }; + + class __recursive_mutex + { + private: + __gthread_recursive_mutex_t _M_mutex; + + __recursive_mutex(const __recursive_mutex&); + __recursive_mutex& operator=(const __recursive_mutex&); + + public: + __recursive_mutex() + { +#if __GTHREADS + if (__gthread_active_p()) + { +#if defined __GTHREAD_RECURSIVE_MUTEX_INIT + __gthread_recursive_mutex_t __tmp = __GTHREAD_RECURSIVE_MUTEX_INIT; + __copy_gthr_type(_M_mutex, __tmp); +#else + __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION(&_M_mutex); +#endif + } +#endif + } + +#if __GTHREADS && ! defined __GTHREAD_RECURSIVE_MUTEX_INIT + ~__recursive_mutex() + { + if (__gthread_active_p()) + _S_destroy(&_M_mutex); + } +#endif + + void lock() + { +#if __GTHREADS + if (__gthread_active_p()) + { + if (__gthread_recursive_mutex_lock(&_M_mutex) != 0) + __throw_concurrence_lock_error(); + } +#endif + } + + void unlock() + { +#if __GTHREADS + if (__gthread_active_p()) + { + if (__gthread_recursive_mutex_unlock(&_M_mutex) != 0) + __throw_concurrence_unlock_error(); + } +#endif + } + + __gthread_recursive_mutex_t* gthread_recursive_mutex(void) + { return &_M_mutex; } + +#if __GTHREADS && ! defined __GTHREAD_RECURSIVE_MUTEX_INIT + // FIXME: gthreads doesn't define __gthread_recursive_mutex_destroy + // so we need to obtain a __gthread_mutex_t to destroy + private: + template<typename _Mx, typename _Rm> + static void + _S_destroy_win32(_Mx* __mx, _Rm const* __rmx) + { + __mx->counter = __rmx->counter; + __mx->sema = __rmx->sema; + __gthread_mutex_destroy(__mx); + } + + // matches a gthr-win32.h recursive mutex + template<typename _Rm> + static typename __enable_if<(bool)sizeof(&_Rm::sema), void>::__type + _S_destroy(_Rm* __mx) + { + __gthread_mutex_t __tmp; + _S_destroy_win32(&__tmp, __mx); + } + + // matches a recursive mutex with a member 'actual' + template<typename _Rm> + static typename __enable_if<(bool)sizeof(&_Rm::actual), void>::__type + _S_destroy(_Rm* __mx) + { __gthread_mutex_destroy(&__mx->actual); } + + // matches when there's only one mutex type + template<typename _Rm> + static typename + __enable_if<std::__are_same<_Rm, __gthread_mutex_t>::__value, + void>::__type + _S_destroy(_Rm* __mx) + { __gthread_mutex_destroy(__mx); } +#endif + }; + + /// Scoped lock idiom. + // Acquire the mutex here with a constructor call, then release with + // the destructor call in accordance with RAII style. + class __scoped_lock + { + public: + typedef __mutex __mutex_type; + + private: + __mutex_type& _M_device; + + __scoped_lock(const __scoped_lock&); + __scoped_lock& operator=(const __scoped_lock&); + + public: + explicit __scoped_lock(__mutex_type& __name) : _M_device(__name) + { _M_device.lock(); } + + ~__scoped_lock() throw() + { _M_device.unlock(); } + }; + +#ifdef __GTHREAD_HAS_COND + class __cond + { + private: + __gthread_cond_t _M_cond; + + __cond(const __cond&); + __cond& operator=(const __cond&); + + public: + __cond() + { +#if __GTHREADS + if (__gthread_active_p()) + { +#if defined __GTHREAD_COND_INIT + __gthread_cond_t __tmp = __GTHREAD_COND_INIT; + __copy_gthr_type(_M_cond, __tmp); +#else + __GTHREAD_COND_INIT_FUNCTION(&_M_cond); +#endif + } +#endif + } + +#if __GTHREADS && ! defined __GTHREAD_COND_INIT + ~__cond() + { + if (__gthread_active_p()) + __gthread_cond_destroy(&_M_cond); + } +#endif + + void broadcast() + { +#if __GTHREADS + if (__gthread_active_p()) + { + if (__gthread_cond_broadcast(&_M_cond) != 0) + __throw_concurrence_broadcast_error(); + } +#endif + } + + void wait(__mutex *mutex) + { +#if __GTHREADS + { + if (__gthread_cond_wait(&_M_cond, mutex->gthread_mutex()) != 0) + __throw_concurrence_wait_error(); + } +#endif + } + + void wait_recursive(__recursive_mutex *mutex) + { +#if __GTHREADS + { + if (__gthread_cond_wait_recursive(&_M_cond, + mutex->gthread_recursive_mutex()) + != 0) + __throw_concurrence_wait_error(); + } +#endif + } + }; +#endif + +_GLIBCXX_END_NAMESPACE_VERSION +} // namespace + +#endif |