1 // -*- C++ -*- 2 //===--------------------------- thread -----------------------------------===// 3 // 4 // The LLVM Compiler Infrastructure 5 // 6 // This file is dual licensed under the MIT and the University of Illinois Open 7 // Source Licenses. See LICENSE.TXT for details. 8 // 9 //===----------------------------------------------------------------------===// 10 11 #ifndef _LIBCPP_THREAD 12 #define _LIBCPP_THREAD 13 14 /* 15 16 thread synopsis 17 18 #define __STDCPP_THREADS__ __cplusplus 19 20 namespace std 21 { 22 23 class thread 24 { 25 public: 26 class id; 27 typedef pthread_t native_handle_type; 28 29 thread() noexcept; 30 template <class F, class ...Args> explicit thread(F&& f, Args&&... args); 31 ~thread(); 32 33 thread(const thread&) = delete; 34 thread(thread&& t) noexcept; 35 36 thread& operator=(const thread&) = delete; 37 thread& operator=(thread&& t) noexcept; 38 39 void swap(thread& t) noexcept; 40 41 bool joinable() const noexcept; 42 void join(); 43 void detach(); 44 id get_id() const noexcept; 45 native_handle_type native_handle(); 46 47 static unsigned hardware_concurrency() noexcept; 48 }; 49 50 void swap(thread& x, thread& y) noexcept; 51 52 class thread::id 53 { 54 public: 55 id() noexcept; 56 }; 57 58 bool operator==(thread::id x, thread::id y) noexcept; 59 bool operator!=(thread::id x, thread::id y) noexcept; 60 bool operator< (thread::id x, thread::id y) noexcept; 61 bool operator<=(thread::id x, thread::id y) noexcept; 62 bool operator> (thread::id x, thread::id y) noexcept; 63 bool operator>=(thread::id x, thread::id y) noexcept; 64 65 template<class charT, class traits> 66 basic_ostream<charT, traits>& 67 operator<<(basic_ostream<charT, traits>& out, thread::id id); 68 69 namespace this_thread 70 { 71 72 thread::id get_id() noexcept; 73 74 void yield() noexcept; 75 76 template <class Clock, class Duration> 77 void sleep_until(const chrono::time_point<Clock, Duration>& abs_time); 78 79 template <class Rep, class Period> 80 void sleep_for(const chrono::duration<Rep, Period>& rel_time); 81 82 } // this_thread 83 84 } // std 85 86 */ 87 88 #include <__config> 89 #include <iosfwd> 90 #include <__functional_base> 91 #include <type_traits> 92 #include <cstddef> 93 #include <functional> 94 #include <memory> 95 #include <system_error> 96 #include <chrono> 97 #include <__mutex_base> 98 #ifndef _LIBCPP_HAS_NO_VARIADICS 99 #include <tuple> 100 #endif 101 #include <pthread.h> 102 103 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 104 #pragma GCC system_header 105 #endif 106 107 #define __STDCPP_THREADS__ __cplusplus 108 109 #if !_LIBCPP_SINGLE_THREADED 110 111 _LIBCPP_BEGIN_NAMESPACE_STD 112 113 template <class _Tp> 114 class __thread_specific_ptr 115 { 116 pthread_key_t __key_; 117 118 __thread_specific_ptr(const __thread_specific_ptr&); 119 __thread_specific_ptr& operator=(const __thread_specific_ptr&); 120 121 static void __at_thread_exit(void*); 122 public: 123 typedef _Tp* pointer; 124 125 __thread_specific_ptr(); 126 ~__thread_specific_ptr(); 127 128 _LIBCPP_INLINE_VISIBILITY 129 pointer get() const {return static_cast<_Tp*>(pthread_getspecific(__key_));} 130 _LIBCPP_INLINE_VISIBILITY 131 pointer operator*() const {return *get();} 132 _LIBCPP_INLINE_VISIBILITY 133 pointer operator->() const {return get();} 134 pointer release(); 135 void reset(pointer __p = nullptr); 136 }; 137 138 template <class _Tp> 139 void 140 __thread_specific_ptr<_Tp>::__at_thread_exit(void* __p) 141 { 142 delete static_cast<pointer>(__p); 143 } 144 145 template <class _Tp> 146 __thread_specific_ptr<_Tp>::__thread_specific_ptr() 147 { 148 int __ec = pthread_key_create(&__key_, &__thread_specific_ptr::__at_thread_exit); 149 #ifndef _LIBCPP_NO_EXCEPTIONS 150 if (__ec) 151 throw system_error(error_code(__ec, system_category()), 152 "__thread_specific_ptr construction failed"); 153 #endif 154 } 155 156 template <class _Tp> 157 __thread_specific_ptr<_Tp>::~__thread_specific_ptr() 158 { 159 pthread_key_delete(__key_); 160 } 161 162 template <class _Tp> 163 typename __thread_specific_ptr<_Tp>::pointer 164 __thread_specific_ptr<_Tp>::release() 165 { 166 pointer __p = get(); 167 pthread_setspecific(__key_, 0); 168 return __p; 169 } 170 171 template <class _Tp> 172 void 173 __thread_specific_ptr<_Tp>::reset(pointer __p) 174 { 175 pointer __p_old = get(); 176 pthread_setspecific(__key_, __p); 177 delete __p_old; 178 } 179 180 class _LIBCPP_TYPE_VIS thread; 181 class _LIBCPP_TYPE_VIS __thread_id; 182 183 namespace this_thread 184 { 185 186 _LIBCPP_INLINE_VISIBILITY __thread_id get_id() _NOEXCEPT; 187 188 } // this_thread 189 190 template<> struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id>; 191 192 class _LIBCPP_TYPE_VIS_ONLY __thread_id 193 { 194 // FIXME: pthread_t is a pointer on Darwin but a long on Linux. 195 // NULL is the no-thread value on Darwin. Someone needs to check 196 // on other platforms. We assume 0 works everywhere for now. 197 pthread_t __id_; 198 199 public: 200 _LIBCPP_INLINE_VISIBILITY 201 __thread_id() _NOEXCEPT : __id_(0) {} 202 203 friend _LIBCPP_INLINE_VISIBILITY 204 bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT 205 {return __x.__id_ == __y.__id_;} 206 friend _LIBCPP_INLINE_VISIBILITY 207 bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT 208 {return !(__x == __y);} 209 friend _LIBCPP_INLINE_VISIBILITY 210 bool operator< (__thread_id __x, __thread_id __y) _NOEXCEPT 211 {return __x.__id_ < __y.__id_;} 212 friend _LIBCPP_INLINE_VISIBILITY 213 bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT 214 {return !(__y < __x);} 215 friend _LIBCPP_INLINE_VISIBILITY 216 bool operator> (__thread_id __x, __thread_id __y) _NOEXCEPT 217 {return __y < __x ;} 218 friend _LIBCPP_INLINE_VISIBILITY 219 bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT 220 {return !(__x < __y);} 221 222 template<class _CharT, class _Traits> 223 friend 224 _LIBCPP_INLINE_VISIBILITY 225 basic_ostream<_CharT, _Traits>& 226 operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id) 227 {return __os << __id.__id_;} 228 229 private: 230 _LIBCPP_INLINE_VISIBILITY 231 __thread_id(pthread_t __id) : __id_(__id) {} 232 233 friend __thread_id this_thread::get_id() _NOEXCEPT; 234 friend class _LIBCPP_TYPE_VIS thread; 235 friend struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id>; 236 }; 237 238 template<> 239 struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id> 240 : public unary_function<__thread_id, size_t> 241 { 242 _LIBCPP_INLINE_VISIBILITY 243 size_t operator()(__thread_id __v) const 244 { 245 return hash<pthread_t>()(__v.__id_); 246 } 247 }; 248 249 namespace this_thread 250 { 251 252 inline _LIBCPP_INLINE_VISIBILITY 253 __thread_id 254 get_id() _NOEXCEPT 255 { 256 return pthread_self(); 257 } 258 259 } // this_thread 260 261 class _LIBCPP_TYPE_VIS thread 262 { 263 pthread_t __t_; 264 265 thread(const thread&); 266 thread& operator=(const thread&); 267 public: 268 typedef __thread_id id; 269 typedef pthread_t native_handle_type; 270 271 _LIBCPP_INLINE_VISIBILITY 272 thread() _NOEXCEPT : __t_(0) {} 273 #ifndef _LIBCPP_HAS_NO_VARIADICS 274 template <class _Fp, class ..._Args, 275 class = typename enable_if 276 < 277 !is_same<typename decay<_Fp>::type, thread>::value 278 >::type 279 > 280 explicit thread(_Fp&& __f, _Args&&... __args); 281 #else // _LIBCPP_HAS_NO_VARIADICS 282 template <class _Fp> explicit thread(_Fp __f); 283 #endif 284 ~thread(); 285 286 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 287 _LIBCPP_INLINE_VISIBILITY 288 thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) {__t.__t_ = 0;} 289 thread& operator=(thread&& __t) _NOEXCEPT; 290 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 291 292 _LIBCPP_INLINE_VISIBILITY 293 void swap(thread& __t) _NOEXCEPT {_VSTD::swap(__t_, __t.__t_);} 294 295 _LIBCPP_INLINE_VISIBILITY 296 bool joinable() const _NOEXCEPT {return __t_ != 0;} 297 void join(); 298 void detach(); 299 _LIBCPP_INLINE_VISIBILITY 300 id get_id() const _NOEXCEPT {return __t_;} 301 _LIBCPP_INLINE_VISIBILITY 302 native_handle_type native_handle() _NOEXCEPT {return __t_;} 303 304 static unsigned hardware_concurrency() _NOEXCEPT; 305 }; 306 307 class __assoc_sub_state; 308 309 class _LIBCPP_HIDDEN __thread_struct_imp; 310 311 class _LIBCPP_TYPE_VIS __thread_struct 312 { 313 __thread_struct_imp* __p_; 314 315 __thread_struct(const __thread_struct&); 316 __thread_struct& operator=(const __thread_struct&); 317 public: 318 __thread_struct(); 319 ~__thread_struct(); 320 321 void notify_all_at_thread_exit(condition_variable*, mutex*); 322 void __make_ready_at_thread_exit(__assoc_sub_state*); 323 }; 324 325 _LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data(); 326 327 #ifndef _LIBCPP_HAS_NO_VARIADICS 328 329 template <class _Fp, class ..._Args, size_t ..._Indices> 330 inline _LIBCPP_INLINE_VISIBILITY 331 void 332 __thread_execute(tuple<_Fp, _Args...>& __t, __tuple_indices<_Indices...>) 333 { 334 __invoke(_VSTD::move(_VSTD::get<0>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...); 335 } 336 337 template <class _Fp> 338 void* 339 __thread_proxy(void* __vp) 340 { 341 __thread_local_data().reset(new __thread_struct); 342 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp)); 343 typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 1>::type _Index; 344 __thread_execute(*__p, _Index()); 345 return nullptr; 346 } 347 348 template <class _Fp, class ..._Args, 349 class 350 > 351 thread::thread(_Fp&& __f, _Args&&... __args) 352 { 353 typedef tuple<typename decay<_Fp>::type, typename decay<_Args>::type...> _Gp; 354 _VSTD::unique_ptr<_Gp> __p(new _Gp(__decay_copy(_VSTD::forward<_Fp>(__f)), 355 __decay_copy(_VSTD::forward<_Args>(__args))...)); 356 int __ec = pthread_create(&__t_, 0, &__thread_proxy<_Gp>, __p.get()); 357 if (__ec == 0) 358 __p.release(); 359 else 360 __throw_system_error(__ec, "thread constructor failed"); 361 } 362 363 #else // _LIBCPP_HAS_NO_VARIADICS 364 365 template <class _Fp> 366 void* 367 __thread_proxy(void* __vp) 368 { 369 __thread_local_data().reset(new __thread_struct); 370 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp)); 371 (*__p)(); 372 return nullptr; 373 } 374 375 template <class _Fp> 376 thread::thread(_Fp __f) 377 { 378 std::unique_ptr<_Fp> __p(new _Fp(__f)); 379 int __ec = pthread_create(&__t_, 0, &__thread_proxy<_Fp>, __p.get()); 380 if (__ec == 0) 381 __p.release(); 382 else 383 __throw_system_error(__ec, "thread constructor failed"); 384 } 385 386 #endif // _LIBCPP_HAS_NO_VARIADICS 387 388 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 389 390 inline _LIBCPP_INLINE_VISIBILITY 391 thread& 392 thread::operator=(thread&& __t) _NOEXCEPT 393 { 394 if (__t_ != 0) 395 terminate(); 396 __t_ = __t.__t_; 397 __t.__t_ = 0; 398 return *this; 399 } 400 401 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 402 403 inline _LIBCPP_INLINE_VISIBILITY 404 void swap(thread& __x, thread& __y) _NOEXCEPT {__x.swap(__y);} 405 406 namespace this_thread 407 { 408 409 _LIBCPP_FUNC_VIS void sleep_for(const chrono::nanoseconds& ns); 410 411 template <class _Rep, class _Period> 412 void 413 sleep_for(const chrono::duration<_Rep, _Period>& __d) 414 { 415 using namespace chrono; 416 if (__d > duration<_Rep, _Period>::zero()) 417 { 418 _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max(); 419 nanoseconds __ns; 420 if (__d < _Max) 421 { 422 __ns = duration_cast<nanoseconds>(__d); 423 if (__ns < __d) 424 ++__ns; 425 } 426 else 427 __ns = nanoseconds::max(); 428 sleep_for(__ns); 429 } 430 } 431 432 template <class _Clock, class _Duration> 433 void 434 sleep_until(const chrono::time_point<_Clock, _Duration>& __t) 435 { 436 using namespace chrono; 437 mutex __mut; 438 condition_variable __cv; 439 unique_lock<mutex> __lk(__mut); 440 while (_Clock::now() < __t) 441 __cv.wait_until(__lk, __t); 442 } 443 444 template <class _Duration> 445 inline _LIBCPP_INLINE_VISIBILITY 446 void 447 sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t) 448 { 449 using namespace chrono; 450 sleep_for(__t - steady_clock::now()); 451 } 452 453 inline _LIBCPP_INLINE_VISIBILITY 454 void yield() _NOEXCEPT {sched_yield();} 455 456 } // this_thread 457 458 _LIBCPP_END_NAMESPACE_STD 459 460 #endif // !_LIBCPP_SINGLE_THREADED 461 462 #endif // _LIBCPP_THREAD 463
