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