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 181 182 #include <__undef_min_max> 183 184 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 185 #pragma GCC system_header 186 #endif 187 188 _LIBCPP_BEGIN_NAMESPACE_STD 189 190 #if !_LIBCPP_SINGLE_THREADED 191 192 class _LIBCPP_TYPE_VIS recursive_mutex 193 { 194 pthread_mutex_t __m_; 195 196 public: 197 recursive_mutex(); 198 ~recursive_mutex(); 199 200 private: 201 recursive_mutex(const recursive_mutex&); // = delete; 202 recursive_mutex& operator=(const recursive_mutex&); // = delete; 203 204 public: 205 void lock(); 206 bool try_lock() _NOEXCEPT; 207 void unlock() _NOEXCEPT; 208 209 typedef pthread_mutex_t* native_handle_type; 210 _LIBCPP_INLINE_VISIBILITY 211 native_handle_type native_handle() {return &__m_;} 212 }; 213 214 class _LIBCPP_TYPE_VIS timed_mutex 215 { 216 mutex __m_; 217 condition_variable __cv_; 218 bool __locked_; 219 public: 220 timed_mutex(); 221 ~timed_mutex(); 222 223 private: 224 timed_mutex(const timed_mutex&); // = delete; 225 timed_mutex& operator=(const timed_mutex&); // = delete; 226 227 public: 228 void lock(); 229 bool try_lock() _NOEXCEPT; 230 template <class _Rep, class _Period> 231 _LIBCPP_INLINE_VISIBILITY 232 bool try_lock_for(const chrono::duration<_Rep, _Period>& __d) 233 {return try_lock_until(chrono::steady_clock::now() + __d);} 234 template <class _Clock, class _Duration> 235 bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t); 236 void unlock() _NOEXCEPT; 237 }; 238 239 template <class _Clock, class _Duration> 240 bool 241 timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) 242 { 243 using namespace chrono; 244 unique_lock<mutex> __lk(__m_); 245 bool no_timeout = _Clock::now() < __t; 246 while (no_timeout && __locked_) 247 no_timeout = __cv_.wait_until(__lk, __t) == cv_status::no_timeout; 248 if (!__locked_) 249 { 250 __locked_ = true; 251 return true; 252 } 253 return false; 254 } 255 256 class _LIBCPP_TYPE_VIS recursive_timed_mutex 257 { 258 mutex __m_; 259 condition_variable __cv_; 260 size_t __count_; 261 pthread_t __id_; 262 public: 263 recursive_timed_mutex(); 264 ~recursive_timed_mutex(); 265 266 private: 267 recursive_timed_mutex(const recursive_timed_mutex&); // = delete; 268 recursive_timed_mutex& operator=(const recursive_timed_mutex&); // = delete; 269 270 public: 271 void lock(); 272 bool try_lock() _NOEXCEPT; 273 template <class _Rep, class _Period> 274 _LIBCPP_INLINE_VISIBILITY 275 bool try_lock_for(const chrono::duration<_Rep, _Period>& __d) 276 {return try_lock_until(chrono::steady_clock::now() + __d);} 277 template <class _Clock, class _Duration> 278 bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t); 279 void unlock() _NOEXCEPT; 280 }; 281 282 template <class _Clock, class _Duration> 283 bool 284 recursive_timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) 285 { 286 using namespace chrono; 287 pthread_t __id = pthread_self(); 288 unique_lock<mutex> lk(__m_); 289 if (pthread_equal(__id, __id_)) 290 { 291 if (__count_ == numeric_limits<size_t>::max()) 292 return false; 293 ++__count_; 294 return true; 295 } 296 bool no_timeout = _Clock::now() < __t; 297 while (no_timeout && __count_ != 0) 298 no_timeout = __cv_.wait_until(lk, __t) == cv_status::no_timeout; 299 if (__count_ == 0) 300 { 301 __count_ = 1; 302 __id_ = __id; 303 return true; 304 } 305 return false; 306 } 307 308 template <class _L0, class _L1> 309 int 310 try_lock(_L0& __l0, _L1& __l1) 311 { 312 unique_lock<_L0> __u0(__l0, try_to_lock); 313 if (__u0.owns_lock()) 314 { 315 if (__l1.try_lock()) 316 { 317 __u0.release(); 318 return -1; 319 } 320 else 321 return 1; 322 } 323 return 0; 324 } 325 326 #ifndef _LIBCPP_HAS_NO_VARIADICS 327 328 template <class _L0, class _L1, class _L2, class... _L3> 329 int 330 try_lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3&... __l3) 331 { 332 int __r = 0; 333 unique_lock<_L0> __u0(__l0, try_to_lock); 334 if (__u0.owns_lock()) 335 { 336 __r = try_lock(__l1, __l2, __l3...); 337 if (__r == -1) 338 __u0.release(); 339 else 340 ++__r; 341 } 342 return __r; 343 } 344 345 #endif // _LIBCPP_HAS_NO_VARIADICS 346 347 template <class _L0, class _L1> 348 void 349 lock(_L0& __l0, _L1& __l1) 350 { 351 while (true) 352 { 353 { 354 unique_lock<_L0> __u0(__l0); 355 if (__l1.try_lock()) 356 { 357 __u0.release(); 358 break; 359 } 360 } 361 sched_yield(); 362 { 363 unique_lock<_L1> __u1(__l1); 364 if (__l0.try_lock()) 365 { 366 __u1.release(); 367 break; 368 } 369 } 370 sched_yield(); 371 } 372 } 373 374 #ifndef _LIBCPP_HAS_NO_VARIADICS 375 376 template <class _L0, class _L1, class _L2, class ..._L3> 377 void 378 __lock_first(int __i, _L0& __l0, _L1& __l1, _L2& __l2, _L3& ...__l3) 379 { 380 while (true) 381 { 382 switch (__i) 383 { 384 case 0: 385 { 386 unique_lock<_L0> __u0(__l0); 387 __i = try_lock(__l1, __l2, __l3...); 388 if (__i == -1) 389 { 390 __u0.release(); 391 return; 392 } 393 } 394 ++__i; 395 sched_yield(); 396 break; 397 case 1: 398 { 399 unique_lock<_L1> __u1(__l1); 400 __i = try_lock(__l2, __l3..., __l0); 401 if (__i == -1) 402 { 403 __u1.release(); 404 return; 405 } 406 } 407 if (__i == sizeof...(_L3) + 1) 408 __i = 0; 409 else 410 __i += 2; 411 sched_yield(); 412 break; 413 default: 414 __lock_first(__i - 2, __l2, __l3..., __l0, __l1); 415 return; 416 } 417 } 418 } 419 420 template <class _L0, class _L1, class _L2, class ..._L3> 421 inline _LIBCPP_INLINE_VISIBILITY 422 void 423 lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3& ...__l3) 424 { 425 __lock_first(0, __l0, __l1, __l2, __l3...); 426 } 427 428 #endif // _LIBCPP_HAS_NO_VARIADICS 429 430 #endif // !_LIBCPP_SINGLE_THREADED 431 432 struct _LIBCPP_TYPE_VIS once_flag; 433 434 #ifndef _LIBCPP_HAS_NO_VARIADICS 435 436 template<class _Callable, class... _Args> 437 _LIBCPP_INLINE_VISIBILITY 438 void call_once(once_flag&, _Callable&&, _Args&&...); 439 440 #else // _LIBCPP_HAS_NO_VARIADICS 441 442 template<class _Callable> 443 _LIBCPP_INLINE_VISIBILITY 444 void call_once(once_flag&, _Callable); 445 446 #endif // _LIBCPP_HAS_NO_VARIADICS 447 448 struct _LIBCPP_TYPE_VIS_ONLY once_flag 449 { 450 _LIBCPP_INLINE_VISIBILITY 451 _LIBCPP_CONSTEXPR 452 once_flag() _NOEXCEPT : __state_(0) {} 453 454 private: 455 once_flag(const once_flag&); // = delete; 456 once_flag& operator=(const once_flag&); // = delete; 457 458 unsigned long __state_; 459 460 #ifndef _LIBCPP_HAS_NO_VARIADICS 461 template<class _Callable, class... _Args> 462 friend 463 void call_once(once_flag&, _Callable&&, _Args&&...); 464 #else // _LIBCPP_HAS_NO_VARIADICS 465 template<class _Callable> 466 friend 467 void call_once(once_flag&, _Callable); 468 #endif // _LIBCPP_HAS_NO_VARIADICS 469 }; 470 471 #ifndef _LIBCPP_HAS_NO_VARIADICS 472 473 template <class _Fp> 474 class __call_once_param 475 { 476 _Fp __f_; 477 public: 478 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 479 _LIBCPP_INLINE_VISIBILITY 480 explicit __call_once_param(_Fp&& __f) : __f_(_VSTD::move(__f)) {} 481 #else 482 _LIBCPP_INLINE_VISIBILITY 483 explicit __call_once_param(const _Fp& __f) : __f_(__f) {} 484 #endif 485 486 _LIBCPP_INLINE_VISIBILITY 487 void operator()() 488 { 489 typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 1>::type _Index; 490 __execute(_Index()); 491 } 492 493 private: 494 template <size_t ..._Indices> 495 _LIBCPP_INLINE_VISIBILITY 496 void __execute(__tuple_indices<_Indices...>) 497 { 498 __invoke(_VSTD::move(_VSTD::get<0>(__f_)), _VSTD::move(_VSTD::get<_Indices>(__f_))...); 499 } 500 }; 501 502 #else 503 504 template <class _Fp> 505 class __call_once_param 506 { 507 _Fp __f_; 508 public: 509 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 510 _LIBCPP_INLINE_VISIBILITY 511 explicit __call_once_param(_Fp&& __f) : __f_(_VSTD::move(__f)) {} 512 #else 513 _LIBCPP_INLINE_VISIBILITY 514 explicit __call_once_param(const _Fp& __f) : __f_(__f) {} 515 #endif 516 517 _LIBCPP_INLINE_VISIBILITY 518 void operator()() 519 { 520 __f_(); 521 } 522 }; 523 524 #endif 525 526 template <class _Fp> 527 void 528 __call_once_proxy(void* __vp) 529 { 530 __call_once_param<_Fp>* __p = static_cast<__call_once_param<_Fp>*>(__vp); 531 (*__p)(); 532 } 533 534 _LIBCPP_FUNC_VIS void __call_once(volatile unsigned long&, void*, void(*)(void*)); 535 536 #ifndef _LIBCPP_HAS_NO_VARIADICS 537 538 template<class _Callable, class... _Args> 539 inline _LIBCPP_INLINE_VISIBILITY 540 void 541 call_once(once_flag& __flag, _Callable&& __func, _Args&&... __args) 542 { 543 if (__flag.__state_ != ~0ul) 544 { 545 typedef tuple<typename decay<_Callable>::type, typename decay<_Args>::type...> _Gp; 546 __call_once_param<_Gp> __p(_Gp(__decay_copy(_VSTD::forward<_Callable>(__func)), 547 __decay_copy(_VSTD::forward<_Args>(__args))...)); 548 __call_once(__flag.__state_, &__p, &__call_once_proxy<_Gp>); 549 } 550 } 551 552 #else // _LIBCPP_HAS_NO_VARIADICS 553 554 template<class _Callable> 555 inline _LIBCPP_INLINE_VISIBILITY 556 void 557 call_once(once_flag& __flag, _Callable __func) 558 { 559 if (__flag.__state_ != ~0ul) 560 { 561 __call_once_param<_Callable> __p(__func); 562 __call_once(__flag.__state_, &__p, &__call_once_proxy<_Callable>); 563 } 564 } 565 566 #endif // _LIBCPP_HAS_NO_VARIADICS 567 568 _LIBCPP_END_NAMESPACE_STD 569 570 #endif // _LIBCPP_MUTEX 571
