libstdc++
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00001 // <thread> -*- C++ -*- 00002 00003 // Copyright (C) 2008-2015 Free Software Foundation, Inc. 00004 // 00005 // This file is part of the GNU ISO C++ Library. This library is free 00006 // software; you can redistribute it and/or modify it under the 00007 // terms of the GNU General Public License as published by the 00008 // Free Software Foundation; either version 3, or (at your option) 00009 // any later version. 00010 00011 // This library is distributed in the hope that it will be useful, 00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00014 // GNU General Public License for more details. 00015 00016 // Under Section 7 of GPL version 3, you are granted additional 00017 // permissions described in the GCC Runtime Library Exception, version 00018 // 3.1, as published by the Free Software Foundation. 00019 00020 // You should have received a copy of the GNU General Public License and 00021 // a copy of the GCC Runtime Library Exception along with this program; 00022 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 00023 // <http://www.gnu.org/licenses/>. 00024 00025 /** @file include/thread 00026 * This is a Standard C++ Library header. 00027 */ 00028 00029 #ifndef _GLIBCXX_THREAD 00030 #define _GLIBCXX_THREAD 1 00031 00032 #pragma GCC system_header 00033 00034 #if __cplusplus < 201103L 00035 # include <bits/c++0x_warning.h> 00036 #else 00037 00038 #include <chrono> 00039 #include <functional> 00040 #include <memory> 00041 #include <bits/functexcept.h> 00042 #include <bits/functional_hash.h> 00043 #include <bits/gthr.h> 00044 00045 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) 00046 00047 namespace std _GLIBCXX_VISIBILITY(default) 00048 { 00049 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00050 00051 /** 00052 * @defgroup threads Threads 00053 * @ingroup concurrency 00054 * 00055 * Classes for thread support. 00056 * @{ 00057 */ 00058 00059 /// thread 00060 class thread 00061 { 00062 public: 00063 typedef __gthread_t native_handle_type; 00064 struct _Impl_base; 00065 typedef shared_ptr<_Impl_base> __shared_base_type; 00066 00067 /// thread::id 00068 class id 00069 { 00070 native_handle_type _M_thread; 00071 00072 public: 00073 id() noexcept : _M_thread() { } 00074 00075 explicit 00076 id(native_handle_type __id) : _M_thread(__id) { } 00077 00078 private: 00079 friend class thread; 00080 friend class hash<thread::id>; 00081 00082 friend bool 00083 operator==(thread::id __x, thread::id __y) noexcept 00084 { return __gthread_equal(__x._M_thread, __y._M_thread); } 00085 00086 friend bool 00087 operator<(thread::id __x, thread::id __y) noexcept 00088 { return __x._M_thread < __y._M_thread; } 00089 00090 template<class _CharT, class _Traits> 00091 friend basic_ostream<_CharT, _Traits>& 00092 operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id); 00093 }; 00094 00095 // Simple base type that the templatized, derived class containing 00096 // an arbitrary functor can be converted to and called. 00097 struct _Impl_base 00098 { 00099 __shared_base_type _M_this_ptr; 00100 00101 inline virtual ~_Impl_base(); 00102 00103 virtual void _M_run() = 0; 00104 }; 00105 00106 template<typename _Callable> 00107 struct _Impl : public _Impl_base 00108 { 00109 _Callable _M_func; 00110 00111 _Impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f)) 00112 { } 00113 00114 void 00115 _M_run() { _M_func(); } 00116 }; 00117 00118 private: 00119 id _M_id; 00120 00121 public: 00122 thread() noexcept = default; 00123 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00124 // 2097. packaged_task constructors should be constrained 00125 thread(thread&) = delete; 00126 thread(const thread&) = delete; 00127 00128 thread(thread&& __t) noexcept 00129 { swap(__t); } 00130 00131 template<typename _Callable, typename... _Args> 00132 explicit 00133 thread(_Callable&& __f, _Args&&... __args) 00134 { 00135 #ifdef GTHR_ACTIVE_PROXY 00136 // Create a reference to pthread_create, not just the gthr weak symbol 00137 _M_start_thread(_M_make_routine(std::__bind_simple( 00138 std::forward<_Callable>(__f), 00139 std::forward<_Args>(__args)...)), 00140 reinterpret_cast<void(*)()>(&pthread_create)); 00141 #else 00142 _M_start_thread(_M_make_routine(std::__bind_simple( 00143 std::forward<_Callable>(__f), 00144 std::forward<_Args>(__args)...))); 00145 #endif 00146 } 00147 00148 ~thread() 00149 { 00150 if (joinable()) 00151 std::terminate(); 00152 } 00153 00154 thread& operator=(const thread&) = delete; 00155 00156 thread& operator=(thread&& __t) noexcept 00157 { 00158 if (joinable()) 00159 std::terminate(); 00160 swap(__t); 00161 return *this; 00162 } 00163 00164 void 00165 swap(thread& __t) noexcept 00166 { std::swap(_M_id, __t._M_id); } 00167 00168 bool 00169 joinable() const noexcept 00170 { return !(_M_id == id()); } 00171 00172 void 00173 join(); 00174 00175 void 00176 detach(); 00177 00178 thread::id 00179 get_id() const noexcept 00180 { return _M_id; } 00181 00182 /** @pre thread is joinable 00183 */ 00184 native_handle_type 00185 native_handle() 00186 { return _M_id._M_thread; } 00187 00188 // Returns a value that hints at the number of hardware thread contexts. 00189 static unsigned int 00190 hardware_concurrency() noexcept; 00191 00192 private: 00193 void 00194 _M_start_thread(__shared_base_type, void (*)()); 00195 00196 void 00197 _M_start_thread(__shared_base_type); 00198 00199 template<typename _Callable> 00200 shared_ptr<_Impl<_Callable>> 00201 _M_make_routine(_Callable&& __f) 00202 { 00203 // Create and allocate full data structure, not base. 00204 return std::make_shared<_Impl<_Callable>>(std::forward<_Callable>(__f)); 00205 } 00206 }; 00207 00208 inline thread::_Impl_base::~_Impl_base() = default; 00209 00210 inline void 00211 swap(thread& __x, thread& __y) noexcept 00212 { __x.swap(__y); } 00213 00214 inline bool 00215 operator!=(thread::id __x, thread::id __y) noexcept 00216 { return !(__x == __y); } 00217 00218 inline bool 00219 operator<=(thread::id __x, thread::id __y) noexcept 00220 { return !(__y < __x); } 00221 00222 inline bool 00223 operator>(thread::id __x, thread::id __y) noexcept 00224 { return __y < __x; } 00225 00226 inline bool 00227 operator>=(thread::id __x, thread::id __y) noexcept 00228 { return !(__x < __y); } 00229 00230 // DR 889. 00231 /// std::hash specialization for thread::id. 00232 template<> 00233 struct hash<thread::id> 00234 : public __hash_base<size_t, thread::id> 00235 { 00236 size_t 00237 operator()(const thread::id& __id) const noexcept 00238 { return std::_Hash_impl::hash(__id._M_thread); } 00239 }; 00240 00241 template<class _CharT, class _Traits> 00242 inline basic_ostream<_CharT, _Traits>& 00243 operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id) 00244 { 00245 if (__id == thread::id()) 00246 return __out << "thread::id of a non-executing thread"; 00247 else 00248 return __out << __id._M_thread; 00249 } 00250 00251 _GLIBCXX_END_NAMESPACE_VERSION 00252 00253 /** @namespace std::this_thread 00254 * @brief ISO C++ 2011 entities sub-namespace for thread. 00255 * 30.3.2 Namespace this_thread. 00256 */ 00257 namespace this_thread 00258 { 00259 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00260 00261 /// get_id 00262 inline thread::id 00263 get_id() noexcept { return thread::id(__gthread_self()); } 00264 00265 /// yield 00266 inline void 00267 yield() noexcept 00268 { 00269 #ifdef _GLIBCXX_USE_SCHED_YIELD 00270 __gthread_yield(); 00271 #endif 00272 } 00273 00274 void 00275 __sleep_for(chrono::seconds, chrono::nanoseconds); 00276 00277 /// sleep_for 00278 template<typename _Rep, typename _Period> 00279 inline void 00280 sleep_for(const chrono::duration<_Rep, _Period>& __rtime) 00281 { 00282 if (__rtime <= __rtime.zero()) 00283 return; 00284 auto __s = chrono::duration_cast<chrono::seconds>(__rtime); 00285 auto __ns = chrono::duration_cast<chrono::nanoseconds>(__rtime - __s); 00286 #ifdef _GLIBCXX_USE_NANOSLEEP 00287 __gthread_time_t __ts = 00288 { 00289 static_cast<std::time_t>(__s.count()), 00290 static_cast<long>(__ns.count()) 00291 }; 00292 ::nanosleep(&__ts, 0); 00293 #else 00294 __sleep_for(__s, __ns); 00295 #endif 00296 } 00297 00298 /// sleep_until 00299 template<typename _Clock, typename _Duration> 00300 inline void 00301 sleep_until(const chrono::time_point<_Clock, _Duration>& __atime) 00302 { 00303 auto __now = _Clock::now(); 00304 if (__now < __atime) 00305 sleep_for(__atime - __now); 00306 } 00307 00308 _GLIBCXX_END_NAMESPACE_VERSION 00309 } 00310 00311 // @} group threads 00312 00313 } // namespace 00314 00315 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1 00316 00317 #endif // C++11 00318 00319 #endif // _GLIBCXX_THREAD