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 _LIBCPP_BEGIN_NAMESPACE_STD 110 111 template <class _Tp> 112 class __thread_specific_ptr 113 { 114 pthread_key_t __key_; 115 116 __thread_specific_ptr(const __thread_specific_ptr&); 117 __thread_specific_ptr& operator=(const __thread_specific_ptr&); 118 119 static void __at_thread_exit(void*); 120 public: 121 typedef _Tp* pointer; 122 123 __thread_specific_ptr(); 124 ~__thread_specific_ptr(); 125 126 _LIBCPP_INLINE_VISIBILITY 127 pointer get() const {return static_cast<_Tp*>(pthread_getspecific(__key_));} 128 _LIBCPP_INLINE_VISIBILITY 129 pointer operator*() const {return *get();} 130 _LIBCPP_INLINE_VISIBILITY 131 pointer operator->() const {return get();} 132 pointer release(); 133 void reset(pointer __p = nullptr); 134 }; 135 136 template <class _Tp> 137 void 138 __thread_specific_ptr<_Tp>::__at_thread_exit(void* __p) 139 { 140 delete static_cast<pointer>(__p); 141 } 142 143 template <class _Tp> 144 __thread_specific_ptr<_Tp>::__thread_specific_ptr() 145 { 146 int __ec = pthread_key_create(&__key_, &__thread_specific_ptr::__at_thread_exit); 147 #ifndef _LIBCPP_NO_EXCEPTIONS 148 if (__ec) 149 throw system_error(error_code(__ec, system_category()), 150 "__thread_specific_ptr construction failed"); 151 #endif 152 } 153 154 template <class _Tp> 155 __thread_specific_ptr<_Tp>::~__thread_specific_ptr() 156 { 157 pthread_key_delete(__key_); 158 } 159 160 template <class _Tp> 161 typename __thread_specific_ptr<_Tp>::pointer 162 __thread_specific_ptr<_Tp>::release() 163 { 164 pointer __p = get(); 165 pthread_setspecific(__key_, 0); 166 return __p; 167 } 168 169 template <class _Tp> 170 void 171 __thread_specific_ptr<_Tp>::reset(pointer __p) 172 { 173 pointer __p_old = get(); 174 pthread_setspecific(__key_, __p); 175 delete __p_old; 176 } 177 178 class _LIBCPP_TYPE_VIS thread; 179 class _LIBCPP_TYPE_VIS __thread_id; 180 181 namespace this_thread 182 { 183 184 _LIBCPP_INLINE_VISIBILITY __thread_id get_id() _NOEXCEPT; 185 186 } // this_thread 187 188 class _LIBCPP_TYPE_VIS __thread_id; 189 template<> struct _LIBCPP_TYPE_VIS hash<__thread_id>; 190 191 class _LIBCPP_TYPE_VIS __thread_id 192 { 193 // FIXME: pthread_t is a pointer on Darwin but a long on Linux. 194 // NULL is the no-thread value on Darwin. Someone needs to check 195 // on other platforms. We assume 0 works everywhere for now. 196 pthread_t __id_; 197 198 public: 199 _LIBCPP_INLINE_VISIBILITY 200 __thread_id() _NOEXCEPT : __id_(0) {} 201 202 friend _LIBCPP_INLINE_VISIBILITY 203 bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT 204 {return __x.__id_ == __y.__id_;} 205 friend _LIBCPP_INLINE_VISIBILITY 206 bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT 207 {return !(__x == __y);} 208 friend _LIBCPP_INLINE_VISIBILITY 209 bool operator< (__thread_id __x, __thread_id __y) _NOEXCEPT 210 {return __x.__id_ < __y.__id_;} 211 friend _LIBCPP_INLINE_VISIBILITY 212 bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT 213 {return !(__y < __x);} 214 friend _LIBCPP_INLINE_VISIBILITY 215 bool operator> (__thread_id __x, __thread_id __y) _NOEXCEPT 216 {return __y < __x ;} 217 friend _LIBCPP_INLINE_VISIBILITY 218 bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT 219 {return !(__x < __y);} 220 221 template<class _CharT, class _Traits> 222 friend 223 _LIBCPP_INLINE_VISIBILITY 224 basic_ostream<_CharT, _Traits>& 225 operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id) 226 {return __os << __id.__id_;} 227 228 private: 229 _LIBCPP_INLINE_VISIBILITY 230 __thread_id(pthread_t __id) : __id_(__id) {} 231 232 friend __thread_id this_thread::get_id() _NOEXCEPT; 233 friend class _LIBCPP_TYPE_VIS thread; 234 friend struct _LIBCPP_TYPE_VIS hash<__thread_id>; 235 }; 236 237 template<> 238 struct _LIBCPP_TYPE_VIS hash<__thread_id> 239 : public unary_function<__thread_id, size_t> 240 { 241 _LIBCPP_INLINE_VISIBILITY 242 size_t operator()(__thread_id __v) const 243 { 244 return hash<pthread_t>()(__v.__id_); 245 } 246 }; 247 248 namespace this_thread 249 { 250 251 inline _LIBCPP_INLINE_VISIBILITY 252 __thread_id 253 get_id() _NOEXCEPT 254 { 255 return pthread_self(); 256 } 257 258 } // this_thread 259 260 class _LIBCPP_TYPE_VIS thread 261 { 262 pthread_t __t_; 263 264 thread(const thread&); 265 thread& operator=(const thread&); 266 public: 267 typedef __thread_id id; 268 typedef pthread_t native_handle_type; 269 270 _LIBCPP_INLINE_VISIBILITY 271 thread() _NOEXCEPT : __t_(0) {} 272 #ifndef _LIBCPP_HAS_NO_VARIADICS 273 template <class _Fp, class ..._Args, 274 class = typename enable_if 275 < 276 !is_same<typename decay<_Fp>::type, thread>::value 277 >::type 278 > 279 explicit thread(_Fp&& __f, _Args&&... __args); 280 #else // _LIBCPP_HAS_NO_VARIADICS 281 template <class _Fp> explicit thread(_Fp __f); 282 #endif 283 ~thread(); 284 285 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 286 _LIBCPP_INLINE_VISIBILITY 287 thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) {__t.__t_ = 0;} 288 thread& operator=(thread&& __t) _NOEXCEPT; 289 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 290 291 _LIBCPP_INLINE_VISIBILITY 292 void swap(thread& __t) _NOEXCEPT {_VSTD::swap(__t_, __t.__t_);} 293 294 _LIBCPP_INLINE_VISIBILITY 295 bool joinable() const _NOEXCEPT {return __t_ != 0;} 296 void join(); 297 void detach(); 298 _LIBCPP_INLINE_VISIBILITY 299 id get_id() const _NOEXCEPT {return __t_;} 300 _LIBCPP_INLINE_VISIBILITY 301 native_handle_type native_handle() _NOEXCEPT {return __t_;} 302 303 static unsigned hardware_concurrency() _NOEXCEPT; 304 }; 305 306 class __assoc_sub_state; 307 308 class _LIBCPP_HIDDEN __thread_struct_imp; 309 310 class __thread_struct 311 { 312 __thread_struct_imp* __p_; 313 314 __thread_struct(const __thread_struct&); 315 __thread_struct& operator=(const __thread_struct&); 316 public: 317 __thread_struct(); 318 ~__thread_struct(); 319 320 void notify_all_at_thread_exit(condition_variable*, mutex*); 321 void __make_ready_at_thread_exit(__assoc_sub_state*); 322 }; 323 324 __thread_specific_ptr<__thread_struct>& __thread_local_data(); 325 326 #ifndef _LIBCPP_HAS_NO_VARIADICS 327 328 template <class _Fp, class ..._Args, size_t ..._Indices> 329 inline _LIBCPP_INLINE_VISIBILITY 330 void 331 __thread_execute(tuple<_Fp, _Args...>& __t, __tuple_indices<_Indices...>) 332 { 333 __invoke(_VSTD::move(_VSTD::get<0>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...); 334 } 335 336 template <class _Fp> 337 void* 338 __thread_proxy(void* __vp) 339 { 340 __thread_local_data().reset(new __thread_struct); 341 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp)); 342 typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 1>::type _Index; 343 __thread_execute(*__p, _Index()); 344 return nullptr; 345 } 346 347 template <class _Fp, class ..._Args, 348 class 349 > 350 thread::thread(_Fp&& __f, _Args&&... __args) 351 { 352 typedef tuple<typename decay<_Fp>::type, typename decay<_Args>::type...> _Gp; 353 _VSTD::unique_ptr<_Gp> __p(new _Gp(__decay_copy(_VSTD::forward<_Fp>(__f)), 354 __decay_copy(_VSTD::forward<_Args>(__args))...)); 355 int __ec = pthread_create(&__t_, 0, &__thread_proxy<_Gp>, __p.get()); 356 if (__ec == 0) 357 __p.release(); 358 else 359 __throw_system_error(__ec, "thread constructor failed"); 360 } 361 362 #else // _LIBCPP_HAS_NO_VARIADICS 363 364 template <class _Fp> 365 void* 366 __thread_proxy(void* __vp) 367 { 368 __thread_local_data().reset(new __thread_struct); 369 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp)); 370 (*__p)(); 371 return nullptr; 372 } 373 374 template <class _Fp> 375 thread::thread(_Fp __f) 376 { 377 std::unique_ptr<_Fp> __p(new _Fp(__f)); 378 int __ec = pthread_create(&__t_, 0, &__thread_proxy<_Fp>, __p.get()); 379 if (__ec == 0) 380 __p.release(); 381 else 382 __throw_system_error(__ec, "thread constructor failed"); 383 } 384 385 #endif // _LIBCPP_HAS_NO_VARIADICS 386 387 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 388 389 inline _LIBCPP_INLINE_VISIBILITY 390 thread& 391 thread::operator=(thread&& __t) _NOEXCEPT 392 { 393 if (__t_ != 0) 394 terminate(); 395 __t_ = __t.__t_; 396 __t.__t_ = 0; 397 return *this; 398 } 399 400 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 401 402 inline _LIBCPP_INLINE_VISIBILITY 403 void swap(thread& __x, thread& __y) _NOEXCEPT {__x.swap(__y);} 404 405 namespace this_thread 406 { 407 408 void sleep_for(const chrono::nanoseconds& ns); 409 410 template <class _Rep, class _Period> 411 void 412 sleep_for(const chrono::duration<_Rep, _Period>& __d) 413 { 414 using namespace chrono; 415 if (__d > duration<_Rep, _Period>::zero()) 416 { 417 _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max(); 418 nanoseconds __ns; 419 if (__d < _Max) 420 { 421 __ns = duration_cast<nanoseconds>(__d); 422 if (__ns < __d) 423 ++__ns; 424 } 425 else 426 __ns = nanoseconds::max(); 427 sleep_for(__ns); 428 } 429 } 430 431 template <class _Clock, class _Duration> 432 void 433 sleep_until(const chrono::time_point<_Clock, _Duration>& __t) 434 { 435 using namespace chrono; 436 mutex __mut; 437 condition_variable __cv; 438 unique_lock<mutex> __lk(__mut); 439 while (_Clock::now() < __t) 440 __cv.wait_until(__lk, __t); 441 } 442 443 template <class _Duration> 444 inline _LIBCPP_INLINE_VISIBILITY 445 void 446 sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t) 447 { 448 using namespace chrono; 449 sleep_for(__t - steady_clock::now()); 450 } 451 452 inline _LIBCPP_INLINE_VISIBILITY 453 void yield() _NOEXCEPT {sched_yield();} 454 455 } // this_thread 456 457 _LIBCPP_END_NAMESPACE_STD 458 459 #endif // _LIBCPP_THREAD 460
