1 // -*- C++ -*- 2 //===--------------------------- mutex ------------------------------------===// 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_MUTEX 12 #define _LIBCPP_MUTEX 13 14 /* 15 mutex synopsis 16 17 namespace std 18 { 19 20 class mutex 21 { 22 public: 23 constexpr mutex() noexcept; 24 ~mutex(); 25 26 mutex(const mutex&) = delete; 27 mutex& operator=(const mutex&) = delete; 28 29 void lock(); 30 bool try_lock(); 31 void unlock(); 32 33 typedef pthread_mutex_t* native_handle_type; 34 native_handle_type native_handle(); 35 }; 36 37 class recursive_mutex 38 { 39 public: 40 recursive_mutex(); 41 ~recursive_mutex(); 42 43 recursive_mutex(const recursive_mutex&) = delete; 44 recursive_mutex& operator=(const recursive_mutex&) = delete; 45 46 void lock(); 47 bool try_lock() noexcept; 48 void unlock(); 49 50 typedef pthread_mutex_t* native_handle_type; 51 native_handle_type native_handle(); 52 }; 53 54 class timed_mutex 55 { 56 public: 57 timed_mutex(); 58 ~timed_mutex(); 59 60 timed_mutex(const timed_mutex&) = delete; 61 timed_mutex& operator=(const timed_mutex&) = delete; 62 63 void lock(); 64 bool try_lock(); 65 template <class Rep, class Period> 66 bool try_lock_for(const chrono::duration<Rep, Period>& rel_time); 67 template <class Clock, class Duration> 68 bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time); 69 void unlock(); 70 }; 71 72 class recursive_timed_mutex 73 { 74 public: 75 recursive_timed_mutex(); 76 ~recursive_timed_mutex(); 77 78 recursive_timed_mutex(const recursive_timed_mutex&) = delete; 79 recursive_timed_mutex& operator=(const recursive_timed_mutex&) = delete; 80 81 void lock(); 82 bool try_lock() noexcept; 83 template <class Rep, class Period> 84 bool try_lock_for(const chrono::duration<Rep, Period>& rel_time); 85 template <class Clock, class Duration> 86 bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time); 87 void unlock(); 88 }; 89 90 struct defer_lock_t {}; 91 struct try_to_lock_t {}; 92 struct adopt_lock_t {}; 93 94 constexpr defer_lock_t defer_lock{}; 95 constexpr try_to_lock_t try_to_lock{}; 96 constexpr adopt_lock_t adopt_lock{}; 97 98 template <class Mutex> 99 class lock_guard 100 { 101 public: 102 typedef Mutex mutex_type; 103 104 explicit lock_guard(mutex_type& m); 105 lock_guard(mutex_type& m, adopt_lock_t); 106 ~lock_guard(); 107 108 lock_guard(lock_guard const&) = delete; 109 lock_guard& operator=(lock_guard const&) = delete; 110 }; 111 112 template <class Mutex> 113 class unique_lock 114 { 115 public: 116 typedef Mutex mutex_type; 117 unique_lock() noexcept; 118 explicit unique_lock(mutex_type& m); 119 unique_lock(mutex_type& m, defer_lock_t) noexcept; 120 unique_lock(mutex_type& m, try_to_lock_t); 121 unique_lock(mutex_type& m, adopt_lock_t); 122 template <class Clock, class Duration> 123 unique_lock(mutex_type& m, const chrono::time_point<Clock, Duration>& abs_time); 124 template <class Rep, class Period> 125 unique_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time); 126 ~unique_lock(); 127 128 unique_lock(unique_lock const&) = delete; 129 unique_lock& operator=(unique_lock const&) = delete; 130 131 unique_lock(unique_lock&& u) noexcept; 132 unique_lock& operator=(unique_lock&& u) noexcept; 133 134 void lock(); 135 bool try_lock(); 136 137 template <class Rep, class Period> 138 bool try_lock_for(const chrono::duration<Rep, Period>& rel_time); 139 template <class Clock, class Duration> 140 bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time); 141 142 void unlock(); 143 144 void swap(unique_lock& u) noexcept; 145 mutex_type* release() noexcept; 146 147 bool owns_lock() const noexcept; 148 explicit operator bool () const noexcept; 149 mutex_type* mutex() const noexcept; 150 }; 151 152 template <class Mutex> 153 void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept; 154 155 template <class L1, class L2, class... L3> 156 int try_lock(L1&, L2&, L3&...); 157 template <class L1, class L2, class... L3> 158 void lock(L1&, L2&, L3&...); 159 160 struct once_flag 161 { 162 constexpr once_flag() noexcept; 163 164 once_flag(const once_flag&) = delete; 165 once_flag& operator=(const once_flag&) = delete; 166 }; 167 168 template<class Callable, class ...Args> 169 void call_once(once_flag& flag, Callable&& func, Args&&... args); 170 171 } // std 172 173 */ 174 175 #include <__config> 176 #include <__mutex_base> 177 #include <functional> 178 #ifndef _LIBCPP_HAS_NO_VARIADICS 179 #include <tuple> 180 #endif 181 #include <sched.h> 182 183 #include <__undef_min_max> 184 185 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 186 #pragma GCC system_header 187 #endif 188 189 _LIBCPP_BEGIN_NAMESPACE_STD 190 191 #ifndef _LIBCPP_HAS_NO_THREADS 192 193 class _LIBCPP_TYPE_VIS recursive_mutex 194 { 195 pthread_mutex_t __m_; 196 197 public: 198 recursive_mutex(); 199 ~recursive_mutex(); 200 201 private: 202 recursive_mutex(const recursive_mutex&); // = delete; 203 recursive_mutex& operator=(const recursive_mutex&); // = delete; 204 205 public: 206 void lock(); 207 bool try_lock() _NOEXCEPT; 208 void unlock() _NOEXCEPT; 209 210 typedef pthread_mutex_t* native_handle_type; 211 _LIBCPP_INLINE_VISIBILITY 212 native_handle_type native_handle() {return &__m_;} 213 }; 214 215 class _LIBCPP_TYPE_VIS timed_mutex 216 { 217 mutex __m_; 218 condition_variable __cv_; 219 bool __locked_; 220 public: 221 timed_mutex(); 222 ~timed_mutex(); 223 224 private: 225 timed_mutex(const timed_mutex&); // = delete; 226 timed_mutex& operator=(const timed_mutex&); // = delete; 227 228 public: 229 void lock(); 230 bool try_lock() _NOEXCEPT; 231 template <class _Rep, class _Period> 232 _LIBCPP_INLINE_VISIBILITY 233 bool try_lock_for(const chrono::duration<_Rep, _Period>& __d) 234 {return try_lock_until(chrono::steady_clock::now() + __d);} 235 template <class _Clock, class _Duration> 236 bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t); 237 void unlock() _NOEXCEPT; 238 }; 239 240 template <class _Clock, class _Duration> 241 bool 242 timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) 243 { 244 using namespace chrono; 245 unique_lock<mutex> __lk(__m_); 246 bool no_timeout = _Clock::now() < __t; 247 while (no_timeout && __locked_) 248 no_timeout = __cv_.wait_until(__lk, __t) == cv_status::no_timeout; 249 if (!__locked_) 250 { 251 __locked_ = true; 252 return true; 253 } 254 return false; 255 } 256 257 class _LIBCPP_TYPE_VIS recursive_timed_mutex 258 { 259 mutex __m_; 260 condition_variable __cv_; 261 size_t __count_; 262 pthread_t __id_; 263 public: 264 recursive_timed_mutex(); 265 ~recursive_timed_mutex(); 266 267 private: 268 recursive_timed_mutex(const recursive_timed_mutex&); // = delete; 269 recursive_timed_mutex& operator=(const recursive_timed_mutex&); // = delete; 270 271 public: 272 void lock(); 273 bool try_lock() _NOEXCEPT; 274 template <class _Rep, class _Period> 275 _LIBCPP_INLINE_VISIBILITY 276 bool try_lock_for(const chrono::duration<_Rep, _Period>& __d) 277 {return try_lock_until(chrono::steady_clock::now() + __d);} 278 template <class _Clock, class _Duration> 279 bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t); 280 void unlock() _NOEXCEPT; 281 }; 282 283 template <class _Clock, class _Duration> 284 bool 285 recursive_timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) 286 { 287 using namespace chrono; 288 pthread_t __id = pthread_self(); 289 unique_lock<mutex> lk(__m_); 290 if (pthread_equal(__id, __id_)) 291 { 292 if (__count_ == numeric_limits<size_t>::max()) 293 return false; 294 ++__count_; 295 return true; 296 } 297 bool no_timeout = _Clock::now() < __t; 298 while (no_timeout && __count_ != 0) 299 no_timeout = __cv_.wait_until(lk, __t) == cv_status::no_timeout; 300 if (__count_ == 0) 301 { 302 __count_ = 1; 303 __id_ = __id; 304 return true; 305 } 306 return false; 307 } 308 309 template <class _L0, class _L1> 310 int 311 try_lock(_L0& __l0, _L1& __l1) 312 { 313 unique_lock<_L0> __u0(__l0, try_to_lock); 314 if (__u0.owns_lock()) 315 { 316 if (__l1.try_lock()) 317 { 318 __u0.release(); 319 return -1; 320 } 321 else 322 return 1; 323 } 324 return 0; 325 } 326 327 #ifndef _LIBCPP_HAS_NO_VARIADICS 328 329 template <class _L0, class _L1, class _L2, class... _L3> 330 int 331 try_lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3&... __l3) 332 { 333 int __r = 0; 334 unique_lock<_L0> __u0(__l0, try_to_lock); 335 if (__u0.owns_lock()) 336 { 337 __r = try_lock(__l1, __l2, __l3...); 338 if (__r == -1) 339 __u0.release(); 340 else 341 ++__r; 342 } 343 return __r; 344 } 345 346 #endif // _LIBCPP_HAS_NO_VARIADICS 347 348 template <class _L0, class _L1> 349 void 350 lock(_L0& __l0, _L1& __l1) 351 { 352 while (true) 353 { 354 { 355 unique_lock<_L0> __u0(__l0); 356 if (__l1.try_lock()) 357 { 358 __u0.release(); 359 break; 360 } 361 } 362 sched_yield(); 363 { 364 unique_lock<_L1> __u1(__l1); 365 if (__l0.try_lock()) 366 { 367 __u1.release(); 368 break; 369 } 370 } 371 sched_yield(); 372 } 373 } 374 375 #ifndef _LIBCPP_HAS_NO_VARIADICS 376 377 template <class _L0, class _L1, class _L2, class ..._L3> 378 void 379 __lock_first(int __i, _L0& __l0, _L1& __l1, _L2& __l2, _L3& ...__l3) 380 { 381 while (true) 382 { 383 switch (__i) 384 { 385 case 0: 386 { 387 unique_lock<_L0> __u0(__l0); 388 __i = try_lock(__l1, __l2, __l3...); 389 if (__i == -1) 390 { 391 __u0.release(); 392 return; 393 } 394 } 395 ++__i; 396 sched_yield(); 397 break; 398 case 1: 399 { 400 unique_lock<_L1> __u1(__l1); 401 __i = try_lock(__l2, __l3..., __l0); 402 if (__i == -1) 403 { 404 __u1.release(); 405 return; 406 } 407 } 408 if (__i == sizeof...(_L3) + 1) 409 __i = 0; 410 else 411 __i += 2; 412 sched_yield(); 413 break; 414 default: 415 __lock_first(__i - 2, __l2, __l3..., __l0, __l1); 416 return; 417 } 418 } 419 } 420 421 template <class _L0, class _L1, class _L2, class ..._L3> 422 inline _LIBCPP_INLINE_VISIBILITY 423 void 424 lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3& ...__l3) 425 { 426 __lock_first(0, __l0, __l1, __l2, __l3...); 427 } 428 429 #endif // _LIBCPP_HAS_NO_VARIADICS 430 431 #endif // !_LIBCPP_HAS_NO_THREADS 432 433 struct _LIBCPP_TYPE_VIS_ONLY once_flag; 434 435 #ifndef _LIBCPP_HAS_NO_VARIADICS 436 437 template<class _Callable, class... _Args> 438 _LIBCPP_INLINE_VISIBILITY 439 void call_once(once_flag&, _Callable&&, _Args&&...); 440 441 #else // _LIBCPP_HAS_NO_VARIADICS 442 443 template<class _Callable> 444 _LIBCPP_INLINE_VISIBILITY 445 void call_once(once_flag&, _Callable); 446 447 #endif // _LIBCPP_HAS_NO_VARIADICS 448 449 struct _LIBCPP_TYPE_VIS_ONLY once_flag 450 { 451 _LIBCPP_INLINE_VISIBILITY 452 _LIBCPP_CONSTEXPR 453 once_flag() _NOEXCEPT : __state_(0) {} 454 455 private: 456 once_flag(const once_flag&); // = delete; 457 once_flag& operator=(const once_flag&); // = delete; 458 459 unsigned long __state_; 460 461 #ifndef _LIBCPP_HAS_NO_VARIADICS 462 template<class _Callable, class... _Args> 463 friend 464 void call_once(once_flag&, _Callable&&, _Args&&...); 465 #else // _LIBCPP_HAS_NO_VARIADICS 466 template<class _Callable> 467 friend 468 void call_once(once_flag&, _Callable); 469 #endif // _LIBCPP_HAS_NO_VARIADICS 470 }; 471 472 #ifndef _LIBCPP_HAS_NO_VARIADICS 473 474 template <class _Fp> 475 class __call_once_param 476 { 477 _Fp __f_; 478 public: 479 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 480 _LIBCPP_INLINE_VISIBILITY 481 explicit __call_once_param(_Fp&& __f) : __f_(_VSTD::move(__f)) {} 482 #else 483 _LIBCPP_INLINE_VISIBILITY 484 explicit __call_once_param(const _Fp& __f) : __f_(__f) {} 485 #endif 486 487 _LIBCPP_INLINE_VISIBILITY 488 void operator()() 489 { 490 typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 1>::type _Index; 491 __execute(_Index()); 492 } 493 494 private: 495 template <size_t ..._Indices> 496 _LIBCPP_INLINE_VISIBILITY 497 void __execute(__tuple_indices<_Indices...>) 498 { 499 __invoke(_VSTD::move(_VSTD::get<0>(__f_)), _VSTD::move(_VSTD::get<_Indices>(__f_))...); 500 } 501 }; 502 503 #else 504 505 template <class _Fp> 506 class __call_once_param 507 { 508 _Fp __f_; 509 public: 510 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 511 _LIBCPP_INLINE_VISIBILITY 512 explicit __call_once_param(_Fp&& __f) : __f_(_VSTD::move(__f)) {} 513 #else 514 _LIBCPP_INLINE_VISIBILITY 515 explicit __call_once_param(const _Fp& __f) : __f_(__f) {} 516 #endif 517 518 _LIBCPP_INLINE_VISIBILITY 519 void operator()() 520 { 521 __f_(); 522 } 523 }; 524 525 #endif 526 527 template <class _Fp> 528 void 529 __call_once_proxy(void* __vp) 530 { 531 __call_once_param<_Fp>* __p = static_cast<__call_once_param<_Fp>*>(__vp); 532 (*__p)(); 533 } 534 535 _LIBCPP_FUNC_VIS void __call_once(volatile unsigned long&, void*, void(*)(void*)); 536 537 #ifndef _LIBCPP_HAS_NO_VARIADICS 538 539 template<class _Callable, class... _Args> 540 inline _LIBCPP_INLINE_VISIBILITY 541 void 542 call_once(once_flag& __flag, _Callable&& __func, _Args&&... __args) 543 { 544 if (__flag.__state_ != ~0ul) 545 { 546 typedef tuple<typename decay<_Callable>::type, typename decay<_Args>::type...> _Gp; 547 __call_once_param<_Gp> __p(_Gp(__decay_copy(_VSTD::forward<_Callable>(__func)), 548 __decay_copy(_VSTD::forward<_Args>(__args))...)); 549 __call_once(__flag.__state_, &__p, &__call_once_proxy<_Gp>); 550 } 551 } 552 553 #else // _LIBCPP_HAS_NO_VARIADICS 554 555 template<class _Callable> 556 inline _LIBCPP_INLINE_VISIBILITY 557 void 558 call_once(once_flag& __flag, _Callable __func) 559 { 560 if (__flag.__state_ != ~0ul) 561 { 562 __call_once_param<_Callable> __p(__func); 563 __call_once(__flag.__state_, &__p, &__call_once_proxy<_Callable>); 564 } 565 } 566 567 #endif // _LIBCPP_HAS_NO_VARIADICS 568 569 _LIBCPP_END_NAMESPACE_STD 570 571 #endif // _LIBCPP_MUTEX 572
