1 // <thread> -*- C++ -*- 2 3 // Copyright (C) 2008-2014 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file include/thread 26 * This is a Standard C++ Library header. 27 */ 28 29 #ifndef _GLIBCXX_THREAD 30 #define _GLIBCXX_THREAD 1 31 32 #pragma GCC system_header 33 34 #if __cplusplus < 201103L 35 # include <bits/c++0x_warning.h> 36 #else 37 38 #include <chrono> 39 #include <functional> 40 #include <memory> 41 #include <bits/functexcept.h> 42 #include <bits/functional_hash.h> 43 #include <bits/gthr.h> 44 45 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) 46 47 namespace std _GLIBCXX_VISIBILITY(default) 48 { 49 _GLIBCXX_BEGIN_NAMESPACE_VERSION 50 51 /** 52 * @defgroup threads Threads 53 * @ingroup concurrency 54 * 55 * Classes for thread support. 56 * @{ 57 */ 58 59 /// thread 60 class thread 61 { 62 public: 63 typedef __gthread_t native_handle_type; 64 struct _Impl_base; 65 typedef shared_ptr<_Impl_base> __shared_base_type; 66 67 /// thread::id 68 class id 69 { 70 native_handle_type _M_thread; 71 72 public: 73 id() noexcept : _M_thread() { } 74 75 explicit 76 id(native_handle_type __id) : _M_thread(__id) { } 77 78 private: 79 friend class thread; 80 friend class hash<thread::id>; 81 82 friend bool 83 operator==(thread::id __x, thread::id __y) noexcept 84 { return __gthread_equal(__x._M_thread, __y._M_thread); } 85 86 friend bool 87 operator<(thread::id __x, thread::id __y) noexcept 88 { return __x._M_thread < __y._M_thread; } 89 90 template<class _CharT, class _Traits> 91 friend basic_ostream<_CharT, _Traits>& 92 operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id); 93 }; 94 95 // Simple base type that the templatized, derived class containing 96 // an arbitrary functor can be converted to and called. 97 struct _Impl_base 98 { 99 __shared_base_type _M_this_ptr; 100 101 inline virtual ~_Impl_base(); 102 103 virtual void _M_run() = 0; 104 }; 105 106 template<typename _Callable> 107 struct _Impl : public _Impl_base 108 { 109 _Callable _M_func; 110 111 _Impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f)) 112 { } 113 114 void 115 _M_run() { _M_func(); } 116 }; 117 118 private: 119 id _M_id; 120 121 public: 122 thread() noexcept = default; 123 // _GLIBCXX_RESOLVE_LIB_DEFECTS 124 // 2097. packaged_task constructors should be constrained 125 thread(thread&) = delete; 126 thread(const thread&) = delete; 127 128 thread(thread&& __t) noexcept 129 { swap(__t); } 130 131 template<typename _Callable, typename... _Args> 132 explicit 133 thread(_Callable&& __f, _Args&&... __args) 134 { 135 _M_start_thread(_M_make_routine(std::__bind_simple( 136 std::forward<_Callable>(__f), 137 std::forward<_Args>(__args)...))); 138 } 139 140 ~thread() 141 { 142 if (joinable()) 143 std::terminate(); 144 } 145 146 thread& operator=(const thread&) = delete; 147 148 thread& operator=(thread&& __t) noexcept 149 { 150 if (joinable()) 151 std::terminate(); 152 swap(__t); 153 return *this; 154 } 155 156 void 157 swap(thread& __t) noexcept 158 { std::swap(_M_id, __t._M_id); } 159 160 bool 161 joinable() const noexcept 162 { return !(_M_id == id()); } 163 164 void 165 join(); 166 167 void 168 detach(); 169 170 thread::id 171 get_id() const noexcept 172 { return _M_id; } 173 174 /** @pre thread is joinable 175 */ 176 native_handle_type 177 native_handle() 178 { return _M_id._M_thread; } 179 180 // Returns a value that hints at the number of hardware thread contexts. 181 static unsigned int 182 hardware_concurrency() noexcept; 183 184 private: 185 void 186 _M_start_thread(__shared_base_type); 187 188 template<typename _Callable> 189 shared_ptr<_Impl<_Callable>> 190 _M_make_routine(_Callable&& __f) 191 { 192 // Create and allocate full data structure, not base. 193 return std::make_shared<_Impl<_Callable>>(std::forward<_Callable>(__f)); 194 } 195 }; 196 197 inline thread::_Impl_base::~_Impl_base() = default; 198 199 inline void 200 swap(thread& __x, thread& __y) noexcept 201 { __x.swap(__y); } 202 203 inline bool 204 operator!=(thread::id __x, thread::id __y) noexcept 205 { return !(__x == __y); } 206 207 inline bool 208 operator<=(thread::id __x, thread::id __y) noexcept 209 { return !(__y < __x); } 210 211 inline bool 212 operator>(thread::id __x, thread::id __y) noexcept 213 { return __y < __x; } 214 215 inline bool 216 operator>=(thread::id __x, thread::id __y) noexcept 217 { return !(__x < __y); } 218 219 // DR 889. 220 /// std::hash specialization for thread::id. 221 template<> 222 struct hash<thread::id> 223 : public __hash_base<size_t, thread::id> 224 { 225 size_t 226 operator()(const thread::id& __id) const noexcept 227 { return std::_Hash_impl::hash(__id._M_thread); } 228 }; 229 230 template<class _CharT, class _Traits> 231 inline basic_ostream<_CharT, _Traits>& 232 operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id) 233 { 234 if (__id == thread::id()) 235 return __out << "thread::id of a non-executing thread"; 236 else 237 return __out << __id._M_thread; 238 } 239 240 _GLIBCXX_END_NAMESPACE_VERSION 241 242 /** @namespace std::this_thread 243 * @brief ISO C++ 2011 entities sub-namespace for thread. 244 * 30.3.2 Namespace this_thread. 245 */ 246 namespace this_thread 247 { 248 _GLIBCXX_BEGIN_NAMESPACE_VERSION 249 250 /// get_id 251 inline thread::id 252 get_id() noexcept { return thread::id(__gthread_self()); } 253 254 /// yield 255 inline void 256 yield() noexcept 257 { 258 #ifdef _GLIBCXX_USE_SCHED_YIELD 259 __gthread_yield(); 260 #endif 261 } 262 263 void 264 __sleep_for(chrono::seconds, chrono::nanoseconds); 265 266 /// sleep_for 267 template<typename _Rep, typename _Period> 268 inline void 269 sleep_for(const chrono::duration<_Rep, _Period>& __rtime) 270 { 271 auto __s = chrono::duration_cast<chrono::seconds>(__rtime); 272 auto __ns = chrono::duration_cast<chrono::nanoseconds>(__rtime - __s); 273 #ifdef _GLIBCXX_USE_NANOSLEEP 274 __gthread_time_t __ts = 275 { 276 static_cast<std::time_t>(__s.count()), 277 static_cast<long>(__ns.count()) 278 }; 279 ::nanosleep(&__ts, 0); 280 #else 281 __sleep_for(__s, __ns); 282 #endif 283 } 284 285 /// sleep_until 286 template<typename _Clock, typename _Duration> 287 inline void 288 sleep_until(const chrono::time_point<_Clock, _Duration>& __atime) 289 { sleep_for(__atime - _Clock::now()); } 290 291 _GLIBCXX_END_NAMESPACE_VERSION 292 } 293 294 // @} group threads 295 296 } // namespace 297 298 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1 299 300 #endif // C++11 301 302 #endif // _GLIBCXX_THREAD 303
