thread revision 232924
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 20namespace std 21{ 22 23class thread 24{ 25public: 26 class id; 27 typedef pthread_t native_handle_type; 28 29 thread(); 30 template <class F, class ...Args> explicit thread(F&& f, Args&&... args); 31 ~thread(); 32 33 thread(const thread&) = delete; 34 thread(thread&& t); 35 36 thread& operator=(const thread&) = delete; 37 thread& operator=(thread&& t); 38 39 void swap(thread& t); 40 41 bool joinable() const; 42 void join(); 43 void detach(); 44 id get_id() const; 45 native_handle_type native_handle(); 46 47 static unsigned hardware_concurrency(); 48}; 49 50void swap(thread& x, thread& y); 51 52class thread::id 53{ 54public: 55 id(); 56}; 57 58bool operator==(thread::id x, thread::id y); 59bool operator!=(thread::id x, thread::id y); 60bool operator< (thread::id x, thread::id y); 61bool operator<=(thread::id x, thread::id y); 62bool operator> (thread::id x, thread::id y); 63bool operator>=(thread::id x, thread::id y); 64 65template<class charT, class traits> 66basic_ostream<charT, traits>& 67operator<<(basic_ostream<charT, traits>& out, thread::id id); 68 69namespace this_thread 70{ 71 72thread::id get_id(); 73 74void yield(); 75 76template <class Clock, class Duration> 77void sleep_until(const chrono::time_point<Clock, Duration>& abs_time); 78 79template <class Rep, class Period> 80void 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 111template <class _Tp> 112class __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*); 120public: 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 136template <class _Tp> 137void 138__thread_specific_ptr<_Tp>::__at_thread_exit(void* __p) 139{ 140 delete static_cast<pointer>(__p); 141} 142 143template <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 152template <class _Tp> 153__thread_specific_ptr<_Tp>::~__thread_specific_ptr() 154{ 155 pthread_key_delete(__key_); 156} 157 158template <class _Tp> 159typename __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 167template <class _Tp> 168void 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 176class thread; 177class __thread_id; 178 179namespace this_thread 180{ 181 182__thread_id get_id(); 183 184} // this_thread 185 186class _LIBCPP_VISIBLE __thread_id; 187template<> struct _LIBCPP_VISIBLE hash<__thread_id>; 188 189class _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 196public: 197 _LIBCPP_INLINE_VISIBILITY 198 __thread_id() : __id_(0) {} 199 200 friend _LIBCPP_INLINE_VISIBILITY 201 bool operator==(__thread_id __x, __thread_id __y) 202 {return __x.__id_ == __y.__id_;} 203 friend _LIBCPP_INLINE_VISIBILITY 204 bool operator!=(__thread_id __x, __thread_id __y) 205 {return !(__x == __y);} 206 friend _LIBCPP_INLINE_VISIBILITY 207 bool operator< (__thread_id __x, __thread_id __y) 208 {return __x.__id_ < __y.__id_;} 209 friend _LIBCPP_INLINE_VISIBILITY 210 bool operator<=(__thread_id __x, __thread_id __y) 211 {return !(__y < __x);} 212 friend _LIBCPP_INLINE_VISIBILITY 213 bool operator> (__thread_id __x, __thread_id __y) 214 {return __y < __x ;} 215 friend _LIBCPP_INLINE_VISIBILITY 216 bool operator>=(__thread_id __x, __thread_id __y) 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 226private: 227 _LIBCPP_INLINE_VISIBILITY 228 __thread_id(pthread_t __id) : __id_(__id) {} 229 230 friend __thread_id this_thread::get_id(); 231 friend class _LIBCPP_VISIBLE thread; 232 friend struct _LIBCPP_VISIBLE hash<__thread_id>; 233}; 234 235template<> 236struct _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 246namespace this_thread 247{ 248 249inline _LIBCPP_INLINE_VISIBILITY 250__thread_id 251get_id() 252{ 253 return pthread_self(); 254} 255 256} // this_thread 257 258class _LIBCPP_VISIBLE thread 259{ 260 pthread_t __t_; 261 262 thread(const thread&); 263 thread& operator=(const thread&); 264public: 265 typedef __thread_id id; 266 typedef pthread_t native_handle_type; 267 268 _LIBCPP_INLINE_VISIBILITY 269 thread() : __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) : __t_(__t.__t_) {__t.__t_ = 0;} 286 thread& operator=(thread&& __t); 287#endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 288 289 _LIBCPP_INLINE_VISIBILITY 290 void swap(thread& __t) {_VSTD::swap(__t_, __t.__t_);} 291 292 _LIBCPP_INLINE_VISIBILITY 293 bool joinable() const {return __t_ != 0;} 294 void join(); 295 void detach(); 296 _LIBCPP_INLINE_VISIBILITY 297 id get_id() const {return __t_;} 298 _LIBCPP_INLINE_VISIBILITY 299 native_handle_type native_handle() {return __t_;} 300 301 static unsigned hardware_concurrency(); 302}; 303 304class __assoc_sub_state; 305 306class _LIBCPP_HIDDEN __thread_struct_imp; 307 308class __thread_struct 309{ 310 __thread_struct_imp* __p_; 311 312 __thread_struct(const __thread_struct&); 313 __thread_struct& operator=(const __thread_struct&); 314public: 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 326template <class _Fp, class ..._Args, size_t ..._Indices> 327inline _LIBCPP_INLINE_VISIBILITY 328void 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 334template <class _Fp> 335void* 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 345template <class _Fp, class ..._Args, 346 class 347 > 348thread::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 362template <class _Fp> 363void* 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 372template <class _Fp> 373thread::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 387inline _LIBCPP_INLINE_VISIBILITY 388thread& 389thread::operator=(thread&& __t) 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 400inline _LIBCPP_INLINE_VISIBILITY 401void swap(thread& __x, thread& __y) {__x.swap(__y);} 402 403namespace this_thread 404{ 405 406void sleep_for(const chrono::nanoseconds& ns); 407 408template <class _Rep, class _Period> 409void 410sleep_for(const chrono::duration<_Rep, _Period>& __d) 411{ 412 using namespace chrono; 413 nanoseconds __ns = duration_cast<nanoseconds>(__d); 414 if (__ns < __d) 415 ++__ns; 416 sleep_for(__ns); 417} 418 419template <class _Clock, class _Duration> 420void 421sleep_until(const chrono::time_point<_Clock, _Duration>& __t) 422{ 423 using namespace chrono; 424 mutex __mut; 425 condition_variable __cv; 426 unique_lock<mutex> __lk(__mut); 427 while (_Clock::now() < __t) 428 __cv.wait_until(__lk, __t); 429} 430 431template <class _Duration> 432inline _LIBCPP_INLINE_VISIBILITY 433void 434sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t) 435{ 436 using namespace chrono; 437 sleep_for(__t - steady_clock::now()); 438} 439 440inline _LIBCPP_INLINE_VISIBILITY 441void yield() {sched_yield();} 442 443} // this_thread 444 445_LIBCPP_END_NAMESPACE_STD 446 447#endif // _LIBCPP_THREAD 448