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