| 1 | /* Copyright (C) 2010-2020 The RetroArch team |
| 2 | * |
| 3 | * --------------------------------------------------------------------------------------- |
| 4 | * The following license statement only applies to this file (rthreads.c). |
| 5 | * --------------------------------------------------------------------------------------- |
| 6 | * |
| 7 | * Permission is hereby granted, free of charge, |
| 8 | * to any person obtaining a copy of this software and associated documentation files (the "Software"), |
| 9 | * to deal in the Software without restriction, including without limitation the rights to |
| 10 | * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, |
| 11 | * and to permit persons to whom the Software is furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. |
| 14 | * |
| 15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, |
| 16 | * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
| 18 | * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, |
| 19 | * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 20 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| 21 | */ |
| 22 | |
| 23 | #ifdef __unix__ |
| 24 | #ifndef __sun__ |
| 25 | #define _POSIX_C_SOURCE 199309 |
| 26 | #endif |
| 27 | #endif |
| 28 | |
| 29 | #include <stdlib.h> |
| 30 | #include <string.h> |
| 31 | |
| 32 | #include <boolean.h> |
| 33 | #include <rthreads/rthreads.h> |
| 34 | |
| 35 | /* with RETRO_WIN32_USE_PTHREADS, pthreads can be used even on win32. Maybe only supported in MSVC>=2005 */ |
| 36 | |
| 37 | #if defined(_WIN32) && !defined(RETRO_WIN32_USE_PTHREADS) |
| 38 | #define USE_WIN32_THREADS |
| 39 | #ifdef _XBOX |
| 40 | #include <xtl.h> |
| 41 | #else |
| 42 | #define WIN32_LEAN_AND_MEAN |
| 43 | #ifndef _WIN32_WINNT |
| 44 | #define _WIN32_WINNT 0x0500 /*_WIN32_WINNT_WIN2K */ |
| 45 | #endif |
| 46 | #include <windows.h> |
| 47 | #include <mmsystem.h> |
| 48 | #endif |
| 49 | #elif defined(GEKKO) |
| 50 | #include <ogc/lwp_watchdog.h> |
| 51 | #include "gx_pthread.h" |
| 52 | #elif defined(_3DS) |
| 53 | #include "ctr_pthread.h" |
| 54 | #else |
| 55 | #include <pthread.h> |
| 56 | #include <time.h> |
| 57 | #endif |
| 58 | |
| 59 | #if defined(VITA) || defined(BSD) || defined(ORBIS) || defined(__mips__) || defined(_3DS) |
| 60 | #include <sys/time.h> |
| 61 | #endif |
| 62 | |
| 63 | #ifdef __MACH__ |
| 64 | #include <mach/clock.h> |
| 65 | #include <mach/mach.h> |
| 66 | #endif |
| 67 | |
| 68 | struct thread_data |
| 69 | { |
| 70 | void (*func)(void*); |
| 71 | void *userdata; |
| 72 | }; |
| 73 | |
| 74 | struct sthread |
| 75 | { |
| 76 | #ifdef USE_WIN32_THREADS |
| 77 | HANDLE thread; |
| 78 | DWORD id; |
| 79 | #else |
| 80 | pthread_t id; |
| 81 | #endif |
| 82 | }; |
| 83 | |
| 84 | struct slock |
| 85 | { |
| 86 | #ifdef USE_WIN32_THREADS |
| 87 | CRITICAL_SECTION lock; |
| 88 | #else |
| 89 | pthread_mutex_t lock; |
| 90 | #endif |
| 91 | }; |
| 92 | |
| 93 | #ifdef USE_WIN32_THREADS |
| 94 | /* The syntax we'll use is mind-bending unless we use a struct. Plus, we might want to store more info later */ |
| 95 | /* This will be used as a linked list immplementing a queue of waiting threads */ |
| 96 | struct queue_entry |
| 97 | { |
| 98 | struct queue_entry *next; |
| 99 | }; |
| 100 | #endif |
| 101 | |
| 102 | struct scond |
| 103 | { |
| 104 | #ifdef USE_WIN32_THREADS |
| 105 | /* With this implementation of scond, we don't have any way of waking |
| 106 | * (or even identifying) specific threads |
| 107 | * But we need to wake them in the order indicated by the queue. |
| 108 | * This potato token will get get passed around every waiter. |
| 109 | * The bearer can test whether he's next, and hold onto the potato if he is. |
| 110 | * When he's done he can then put it back into play to progress |
| 111 | * the queue further */ |
| 112 | HANDLE hot_potato; |
| 113 | |
| 114 | /* The primary signalled event. Hot potatoes are passed until this is set. */ |
| 115 | HANDLE event; |
| 116 | |
| 117 | /* the head of the queue; NULL if queue is empty */ |
| 118 | struct queue_entry *head; |
| 119 | |
| 120 | /* equivalent to the queue length */ |
| 121 | int waiters; |
| 122 | |
| 123 | /* how many waiters in the queue have been conceptually wakened by signals |
| 124 | * (even if we haven't managed to actually wake them yet) */ |
| 125 | int wakens; |
| 126 | |
| 127 | /* used to control access to this scond, in case the user fails */ |
| 128 | CRITICAL_SECTION cs; |
| 129 | |
| 130 | #else |
| 131 | pthread_cond_t cond; |
| 132 | #endif |
| 133 | }; |
| 134 | |
| 135 | #ifdef USE_WIN32_THREADS |
| 136 | static DWORD CALLBACK thread_wrap(void *data_) |
| 137 | #else |
| 138 | static void *thread_wrap(void *data_) |
| 139 | #endif |
| 140 | { |
| 141 | struct thread_data *data = (struct thread_data*)data_; |
| 142 | if (!data) |
| 143 | return 0; |
| 144 | data->func(data->userdata); |
| 145 | free(data); |
| 146 | return 0; |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * sthread_create: |
| 151 | * @start_routine : thread entry callback function |
| 152 | * @userdata : pointer to userdata that will be made |
| 153 | * available in thread entry callback function |
| 154 | * |
| 155 | * Create a new thread. |
| 156 | * |
| 157 | * Returns: pointer to new thread if successful, otherwise NULL. |
| 158 | */ |
| 159 | sthread_t *sthread_create(void (*thread_func)(void*), void *userdata) |
| 160 | { |
| 161 | return sthread_create_with_priority(thread_func, userdata, 0); |
| 162 | } |
| 163 | |
| 164 | /* TODO/FIXME - this needs to be implemented for Switch/3DS */ |
| 165 | #if !defined(SWITCH) && !defined(USE_WIN32_THREADS) && !defined(_3DS) && !defined(GEKKO) && !defined(__HAIKU__) && !defined(EMSCRIPTEN) |
| 166 | #define HAVE_THREAD_ATTR |
| 167 | #endif |
| 168 | |
| 169 | /** |
| 170 | * sthread_create_with_priority: |
| 171 | * @start_routine : thread entry callback function |
| 172 | * @userdata : pointer to userdata that will be made |
| 173 | * available in thread entry callback function |
| 174 | * @thread_priority : thread priority hint value from [1-100] |
| 175 | * |
| 176 | * Create a new thread. It is possible for the caller to give a hint |
| 177 | * for the thread's priority from [1-100]. Any passed in @thread_priority |
| 178 | * values that are outside of this range will cause sthread_create() to |
| 179 | * create a new thread using the operating system's default thread |
| 180 | * priority. |
| 181 | * |
| 182 | * Returns: pointer to new thread if successful, otherwise NULL. |
| 183 | */ |
| 184 | sthread_t *sthread_create_with_priority(void (*thread_func)(void*), void *userdata, int thread_priority) |
| 185 | { |
| 186 | #ifdef HAVE_THREAD_ATTR |
| 187 | pthread_attr_t thread_attr; |
| 188 | bool thread_attr_needed = false; |
| 189 | #endif |
| 190 | bool thread_created = false; |
| 191 | struct thread_data *data = NULL; |
| 192 | sthread_t *thread = (sthread_t*)malloc(sizeof(*thread)); |
| 193 | |
| 194 | if (!thread) |
| 195 | return NULL; |
| 196 | |
| 197 | if (!(data = (struct thread_data*)malloc(sizeof(*data)))) |
| 198 | { |
| 199 | free(thread); |
| 200 | return NULL; |
| 201 | } |
| 202 | |
| 203 | data->func = thread_func; |
| 204 | data->userdata = userdata; |
| 205 | |
| 206 | thread->id = 0; |
| 207 | #ifdef USE_WIN32_THREADS |
| 208 | thread->thread = CreateThread(NULL, 0, thread_wrap, |
| 209 | data, 0, &thread->id); |
| 210 | thread_created = !!thread->thread; |
| 211 | #else |
| 212 | #ifdef HAVE_THREAD_ATTR |
| 213 | pthread_attr_init(&thread_attr); |
| 214 | |
| 215 | if ((thread_priority >= 1) && (thread_priority <= 100)) |
| 216 | { |
| 217 | struct sched_param sp; |
| 218 | memset(&sp, 0, sizeof(struct sched_param)); |
| 219 | sp.sched_priority = thread_priority; |
| 220 | pthread_attr_setschedpolicy(&thread_attr, SCHED_RR); |
| 221 | pthread_attr_setschedparam(&thread_attr, &sp); |
| 222 | |
| 223 | thread_attr_needed = true; |
| 224 | } |
| 225 | |
| 226 | #if defined(VITA) |
| 227 | pthread_attr_setstacksize(&thread_attr , 0x10000 ); |
| 228 | thread_attr_needed = true; |
| 229 | #elif defined(__APPLE__) |
| 230 | /* Default stack size on Apple is 512Kb; |
| 231 | * for PS2 disc scanning and other reasons, we'd like 2MB. */ |
| 232 | pthread_attr_setstacksize(&thread_attr , 0x200000 ); |
| 233 | thread_attr_needed = true; |
| 234 | #endif |
| 235 | |
| 236 | if (thread_attr_needed) |
| 237 | thread_created = pthread_create(&thread->id, &thread_attr, thread_wrap, data) == 0; |
| 238 | else |
| 239 | thread_created = pthread_create(&thread->id, NULL, thread_wrap, data) == 0; |
| 240 | |
| 241 | pthread_attr_destroy(&thread_attr); |
| 242 | #else |
| 243 | thread_created = pthread_create(&thread->id, NULL, thread_wrap, data) == 0; |
| 244 | #endif |
| 245 | |
| 246 | #endif |
| 247 | |
| 248 | if (thread_created) |
| 249 | return thread; |
| 250 | free(data); |
| 251 | free(thread); |
| 252 | return NULL; |
| 253 | } |
| 254 | |
| 255 | /** |
| 256 | * sthread_detach: |
| 257 | * @thread : pointer to thread object |
| 258 | * |
| 259 | * Detach a thread. When a detached thread terminates, its |
| 260 | * resources are automatically released back to the system |
| 261 | * without the need for another thread to join with the |
| 262 | * terminated thread. |
| 263 | * |
| 264 | * Returns: 0 on success, otherwise it returns a non-zero error number. |
| 265 | */ |
| 266 | int sthread_detach(sthread_t *thread) |
| 267 | { |
| 268 | #ifdef USE_WIN32_THREADS |
| 269 | CloseHandle(thread->thread); |
| 270 | free(thread); |
| 271 | return 0; |
| 272 | #else |
| 273 | int ret = pthread_detach(thread->id); |
| 274 | free(thread); |
| 275 | return ret; |
| 276 | #endif |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | * sthread_join: |
| 281 | * @thread : pointer to thread object |
| 282 | * |
| 283 | * Join with a terminated thread. Waits for the thread specified by |
| 284 | * @thread to terminate. If that thread has already terminated, then |
| 285 | * it will return immediately. The thread specified by @thread must |
| 286 | * be joinable. |
| 287 | * |
| 288 | * Returns: 0 on success, otherwise it returns a non-zero error number. |
| 289 | */ |
| 290 | void sthread_join(sthread_t *thread) |
| 291 | { |
| 292 | if (!thread) |
| 293 | return; |
| 294 | #ifdef USE_WIN32_THREADS |
| 295 | WaitForSingleObject(thread->thread, INFINITE); |
| 296 | CloseHandle(thread->thread); |
| 297 | #else |
| 298 | pthread_join(thread->id, NULL); |
| 299 | #endif |
| 300 | free(thread); |
| 301 | } |
| 302 | |
| 303 | #if !defined(GEKKO) |
| 304 | /** |
| 305 | * sthread_isself: |
| 306 | * @thread : pointer to thread object |
| 307 | * |
| 308 | * Returns: true (1) if calling thread is the specified thread |
| 309 | */ |
| 310 | bool sthread_isself(sthread_t *thread) |
| 311 | { |
| 312 | #ifdef USE_WIN32_THREADS |
| 313 | return thread ? GetCurrentThreadId() == thread->id : false; |
| 314 | #else |
| 315 | return thread ? pthread_equal(pthread_self(), thread->id) : false; |
| 316 | #endif |
| 317 | } |
| 318 | #endif |
| 319 | |
| 320 | /** |
| 321 | * slock_new: |
| 322 | * |
| 323 | * Create and initialize a new mutex. Must be manually |
| 324 | * freed. |
| 325 | * |
| 326 | * Returns: pointer to a new mutex if successful, otherwise NULL. |
| 327 | **/ |
| 328 | slock_t *slock_new(void) |
| 329 | { |
| 330 | slock_t *lock = (slock_t*)calloc(1, sizeof(*lock)); |
| 331 | if (!lock) |
| 332 | return NULL; |
| 333 | #ifdef USE_WIN32_THREADS |
| 334 | InitializeCriticalSection(&lock->lock); |
| 335 | #else |
| 336 | if (pthread_mutex_init(&lock->lock, NULL) != 0) |
| 337 | { |
| 338 | free(lock); |
| 339 | return NULL; |
| 340 | } |
| 341 | #endif |
| 342 | return lock; |
| 343 | } |
| 344 | |
| 345 | /** |
| 346 | * slock_free: |
| 347 | * @lock : pointer to mutex object |
| 348 | * |
| 349 | * Frees a mutex. |
| 350 | **/ |
| 351 | void slock_free(slock_t *lock) |
| 352 | { |
| 353 | if (!lock) |
| 354 | return; |
| 355 | |
| 356 | #ifdef USE_WIN32_THREADS |
| 357 | DeleteCriticalSection(&lock->lock); |
| 358 | #else |
| 359 | pthread_mutex_destroy(&lock->lock); |
| 360 | #endif |
| 361 | free(lock); |
| 362 | } |
| 363 | |
| 364 | /** |
| 365 | * slock_lock: |
| 366 | * @lock : pointer to mutex object |
| 367 | * |
| 368 | * Locks a mutex. If a mutex is already locked by |
| 369 | * another thread, the calling thread shall block until |
| 370 | * the mutex becomes available. |
| 371 | **/ |
| 372 | void slock_lock(slock_t *lock) |
| 373 | { |
| 374 | if (!lock) |
| 375 | return; |
| 376 | #ifdef USE_WIN32_THREADS |
| 377 | EnterCriticalSection(&lock->lock); |
| 378 | #else |
| 379 | pthread_mutex_lock(&lock->lock); |
| 380 | #endif |
| 381 | } |
| 382 | |
| 383 | /** |
| 384 | * slock_try_lock: |
| 385 | * @lock : pointer to mutex object |
| 386 | * |
| 387 | * Attempts to lock a mutex. If a mutex is already locked by |
| 388 | * another thread, return false. If the lock is acquired, return true. |
| 389 | **/ |
| 390 | bool slock_try_lock(slock_t *lock) |
| 391 | { |
| 392 | #ifdef USE_WIN32_THREADS |
| 393 | return lock && TryEnterCriticalSection(&lock->lock); |
| 394 | #else |
| 395 | return lock && (pthread_mutex_trylock(&lock->lock) == 0); |
| 396 | #endif |
| 397 | } |
| 398 | |
| 399 | /** |
| 400 | * slock_unlock: |
| 401 | * @lock : pointer to mutex object |
| 402 | * |
| 403 | * Unlocks a mutex. |
| 404 | **/ |
| 405 | void slock_unlock(slock_t *lock) |
| 406 | { |
| 407 | if (!lock) |
| 408 | return; |
| 409 | #ifdef USE_WIN32_THREADS |
| 410 | LeaveCriticalSection(&lock->lock); |
| 411 | #else |
| 412 | pthread_mutex_unlock(&lock->lock); |
| 413 | #endif |
| 414 | } |
| 415 | |
| 416 | /** |
| 417 | * scond_new: |
| 418 | * |
| 419 | * Creates and initializes a condition variable. Must |
| 420 | * be manually freed. |
| 421 | * |
| 422 | * Returns: pointer to new condition variable on success, |
| 423 | * otherwise NULL. |
| 424 | **/ |
| 425 | scond_t *scond_new(void) |
| 426 | { |
| 427 | scond_t *cond = (scond_t*)calloc(1, sizeof(*cond)); |
| 428 | |
| 429 | if (!cond) |
| 430 | return NULL; |
| 431 | |
| 432 | #ifdef USE_WIN32_THREADS |
| 433 | /* This is very complex because recreating condition variable semantics |
| 434 | * with Win32 parts is not easy. |
| 435 | * |
| 436 | * The main problem is that a condition variable can't be used to |
| 437 | * "pre-wake" a thread (it will get wakened only after it's waited). |
| 438 | * |
| 439 | * Whereas a win32 event can pre-wake a thread (the event will be set |
| 440 | * in advance, so a 'waiter' won't even have to wait on it). |
| 441 | * |
| 442 | * Keep in mind a condition variable can apparently pre-wake a thread, |
| 443 | * insofar as spurious wakeups are always possible, |
| 444 | * but nobody will be expecting this and it does not need to be simulated. |
| 445 | * |
| 446 | * Moreover, we won't be doing this, because it counts as a spurious wakeup |
| 447 | * -- someone else with a genuine claim must get wakened, in any case. |
| 448 | * |
| 449 | * Therefore we choose to wake only one of the correct waiting threads. |
| 450 | * So at the very least, we need to do something clever. But there's |
| 451 | * bigger problems. |
| 452 | * We don't even have a straightforward way in win32 to satisfy |
| 453 | * pthread_cond_wait's atomicity requirement. The bulk of this |
| 454 | * algorithm is solving that. |
| 455 | * |
| 456 | * Note: We might could simplify this using vista+ condition variables, |
| 457 | * but we wanted an XP compatible solution. */ |
| 458 | if (!(cond->event = CreateEvent(NULL, FALSE, FALSE, NULL))) |
| 459 | goto error; |
| 460 | if (!(cond->hot_potato = CreateEvent(NULL, FALSE, FALSE, NULL))) |
| 461 | { |
| 462 | CloseHandle(cond->event); |
| 463 | goto error; |
| 464 | } |
| 465 | |
| 466 | InitializeCriticalSection(&cond->cs); |
| 467 | #else |
| 468 | if (pthread_cond_init(&cond->cond, NULL) != 0) |
| 469 | goto error; |
| 470 | #endif |
| 471 | |
| 472 | return cond; |
| 473 | |
| 474 | error: |
| 475 | free(cond); |
| 476 | return NULL; |
| 477 | } |
| 478 | |
| 479 | /** |
| 480 | * scond_free: |
| 481 | * @cond : pointer to condition variable object |
| 482 | * |
| 483 | * Frees a condition variable. |
| 484 | **/ |
| 485 | void scond_free(scond_t *cond) |
| 486 | { |
| 487 | if (!cond) |
| 488 | return; |
| 489 | |
| 490 | #ifdef USE_WIN32_THREADS |
| 491 | CloseHandle(cond->event); |
| 492 | CloseHandle(cond->hot_potato); |
| 493 | DeleteCriticalSection(&cond->cs); |
| 494 | #else |
| 495 | pthread_cond_destroy(&cond->cond); |
| 496 | #endif |
| 497 | free(cond); |
| 498 | } |
| 499 | |
| 500 | #ifdef USE_WIN32_THREADS |
| 501 | static bool _scond_wait_win32(scond_t *cond, slock_t *lock, DWORD dwMilliseconds) |
| 502 | { |
| 503 | struct queue_entry myentry; |
| 504 | struct queue_entry **ptr; |
| 505 | |
| 506 | #if _WIN32_WINNT >= 0x0500 || defined(_XBOX) |
| 507 | static LARGE_INTEGER performanceCounterFrequency; |
| 508 | LARGE_INTEGER tsBegin; |
| 509 | static bool first_init = true; |
| 510 | #else |
| 511 | static bool beginPeriod = false; |
| 512 | DWORD tsBegin; |
| 513 | #endif |
| 514 | DWORD waitResult; |
| 515 | DWORD dwFinalTimeout = dwMilliseconds; /* Careful! in case we begin in the head, |
| 516 | we don't do the hot potato stuff, |
| 517 | so this timeout needs presetting. */ |
| 518 | |
| 519 | /* Reminder: `lock` is held before this is called. */ |
| 520 | /* however, someone else may have called scond_signal without the lock. soo... */ |
| 521 | EnterCriticalSection(&cond->cs); |
| 522 | |
| 523 | /* since this library is meant for realtime game software |
| 524 | * I have no problem setting this to 1 and forgetting about it. */ |
| 525 | #if _WIN32_WINNT >= 0x0500 || defined(_XBOX) |
| 526 | if (first_init) |
| 527 | { |
| 528 | performanceCounterFrequency.QuadPart = 0; |
| 529 | first_init = false; |
| 530 | } |
| 531 | |
| 532 | if (performanceCounterFrequency.QuadPart == 0) |
| 533 | QueryPerformanceFrequency(&performanceCounterFrequency); |
| 534 | #else |
| 535 | if (!beginPeriod) |
| 536 | { |
| 537 | beginPeriod = true; |
| 538 | timeBeginPeriod(1); |
| 539 | } |
| 540 | #endif |
| 541 | |
| 542 | /* Now we can take a good timestamp for use in faking the timeout ourselves. */ |
| 543 | /* But don't bother unless we need to (to save a little time) */ |
| 544 | if (dwMilliseconds != INFINITE) |
| 545 | #if _WIN32_WINNT >= 0x0500 || defined(_XBOX) |
| 546 | QueryPerformanceCounter(&tsBegin); |
| 547 | #else |
| 548 | tsBegin = timeGetTime(); |
| 549 | #endif |
| 550 | |
| 551 | /* add ourselves to a queue of waiting threads */ |
| 552 | ptr = &cond->head; |
| 553 | |
| 554 | /* walk to the end of the linked list */ |
| 555 | while (*ptr) |
| 556 | ptr = &((*ptr)->next); |
| 557 | |
| 558 | *ptr = &myentry; |
| 559 | myentry.next = NULL; |
| 560 | |
| 561 | cond->waiters++; |
| 562 | |
| 563 | /* now the conceptual lock release and condition block are supposed to be atomic. |
| 564 | * we can't do that in Windows, but we can simulate the effects by using |
| 565 | * the queue, by the following analysis: |
| 566 | * What happens if they aren't atomic? |
| 567 | * |
| 568 | * 1. a signaller can rush in and signal, expecting a waiter to get it; |
| 569 | * but the waiter wouldn't, because he isn't blocked yet. |
| 570 | * Solution: Win32 events make this easy. The event will sit there enabled |
| 571 | * |
| 572 | * 2. a signaller can rush in and signal, and then turn right around and wait. |
| 573 | * Solution: the signaller will get queued behind the waiter, who's |
| 574 | * enqueued before he releases the mutex. */ |
| 575 | |
| 576 | /* It's my turn if I'm the head of the queue. |
| 577 | * Check to see if it's my turn. */ |
| 578 | while (cond->head != &myentry) |
| 579 | { |
| 580 | /* It isn't my turn: */ |
| 581 | DWORD timeout = INFINITE; |
| 582 | |
| 583 | /* As long as someone is even going to be able to wake up |
| 584 | * when they receive the potato, keep it going round. */ |
| 585 | if (cond->wakens > 0) |
| 586 | SetEvent(cond->hot_potato); |
| 587 | |
| 588 | /* Assess the remaining timeout time */ |
| 589 | if (dwMilliseconds != INFINITE) |
| 590 | { |
| 591 | #if _WIN32_WINNT >= 0x0500 || defined(_XBOX) |
| 592 | LARGE_INTEGER now; |
| 593 | LONGLONG elapsed; |
| 594 | |
| 595 | QueryPerformanceCounter(&now); |
| 596 | elapsed = now.QuadPart - tsBegin.QuadPart; |
| 597 | elapsed *= 1000; |
| 598 | elapsed /= performanceCounterFrequency.QuadPart; |
| 599 | #else |
| 600 | DWORD now = timeGetTime(); |
| 601 | DWORD elapsed = now - tsBegin; |
| 602 | #endif |
| 603 | |
| 604 | /* Try one last time with a zero timeout (keeps the code simpler) */ |
| 605 | if (elapsed > dwMilliseconds) |
| 606 | elapsed = dwMilliseconds; |
| 607 | |
| 608 | timeout = dwMilliseconds - elapsed; |
| 609 | } |
| 610 | |
| 611 | /* Let someone else go */ |
| 612 | LeaveCriticalSection(&lock->lock); |
| 613 | LeaveCriticalSection(&cond->cs); |
| 614 | |
| 615 | /* Wait a while to catch the hot potato.. |
| 616 | * someone else should get a chance to go */ |
| 617 | /* After all, it isn't my turn (and it must be someone else's) */ |
| 618 | Sleep(0); |
| 619 | waitResult = WaitForSingleObject(cond->hot_potato, timeout); |
| 620 | |
| 621 | /* I should come out of here with the main lock taken */ |
| 622 | EnterCriticalSection(&lock->lock); |
| 623 | EnterCriticalSection(&cond->cs); |
| 624 | |
| 625 | if (waitResult == WAIT_TIMEOUT) |
| 626 | { |
| 627 | /* Out of time! Now, let's think about this. I do have the potato now-- |
| 628 | * maybe it's my turn, and I have the event? |
| 629 | * If that's the case, I could proceed right now without aborting |
| 630 | * due to timeout. |
| 631 | * |
| 632 | * However.. I DID wait a real long time. The caller was willing |
| 633 | * to wait that long. |
| 634 | * |
| 635 | * I choose to give him one last chance with a zero timeout |
| 636 | * in the next step |
| 637 | */ |
| 638 | if (cond->head == &myentry) |
| 639 | { |
| 640 | dwFinalTimeout = 0; |
| 641 | break; |
| 642 | } |
| 643 | else |
| 644 | { |
| 645 | /* It's not our turn and we're out of time. Give up. |
| 646 | * Remove ourself from the queue and bail. */ |
| 647 | struct queue_entry *curr = cond->head; |
| 648 | |
| 649 | while (curr->next != &myentry) |
| 650 | curr = curr->next; |
| 651 | curr->next = myentry.next; |
| 652 | cond->waiters--; |
| 653 | LeaveCriticalSection(&cond->cs); |
| 654 | return false; |
| 655 | } |
| 656 | } |
| 657 | |
| 658 | } |
| 659 | |
| 660 | /* It's my turn now -- and I hold the potato */ |
| 661 | |
| 662 | /* I still have the main lock, in any case */ |
| 663 | /* I need to release it so that someone can set the event */ |
| 664 | LeaveCriticalSection(&lock->lock); |
| 665 | LeaveCriticalSection(&cond->cs); |
| 666 | |
| 667 | /* Wait for someone to actually signal this condition */ |
| 668 | /* We're the only waiter waiting on the event right now -- everyone else |
| 669 | * is waiting on something different */ |
| 670 | waitResult = WaitForSingleObject(cond->event, dwFinalTimeout); |
| 671 | |
| 672 | /* Take the main lock so we can do work. Nobody else waits on this lock |
| 673 | * for very long, so even though it's GO TIME we won't have to wait long */ |
| 674 | EnterCriticalSection(&lock->lock); |
| 675 | EnterCriticalSection(&cond->cs); |
| 676 | |
| 677 | /* Remove ourselves from the queue */ |
| 678 | cond->head = myentry.next; |
| 679 | cond->waiters--; |
| 680 | |
| 681 | if (waitResult == WAIT_TIMEOUT) |
| 682 | { |
| 683 | /* Oops! ran out of time in the final wait. Just bail. */ |
| 684 | LeaveCriticalSection(&cond->cs); |
| 685 | return false; |
| 686 | } |
| 687 | |
| 688 | /* If any other wakenings are pending, go ahead and set it up */ |
| 689 | /* There may actually be no waiters. That's OK. The first waiter will come in, |
| 690 | * find it's his turn, and immediately get the signaled event */ |
| 691 | cond->wakens--; |
| 692 | if (cond->wakens > 0) |
| 693 | { |
| 694 | SetEvent(cond->event); |
| 695 | |
| 696 | /* Progress the queue: Put the hot potato back into play. It'll be |
| 697 | * tossed around until next in line gets it */ |
| 698 | SetEvent(cond->hot_potato); |
| 699 | } |
| 700 | |
| 701 | LeaveCriticalSection(&cond->cs); |
| 702 | return true; |
| 703 | } |
| 704 | #endif |
| 705 | |
| 706 | /** |
| 707 | * scond_wait: |
| 708 | * @cond : pointer to condition variable object |
| 709 | * @lock : pointer to mutex object |
| 710 | * |
| 711 | * Block on a condition variable (i.e. wait on a condition). |
| 712 | **/ |
| 713 | void scond_wait(scond_t *cond, slock_t *lock) |
| 714 | { |
| 715 | #ifdef USE_WIN32_THREADS |
| 716 | _scond_wait_win32(cond, lock, INFINITE); |
| 717 | #else |
| 718 | pthread_cond_wait(&cond->cond, &lock->lock); |
| 719 | #endif |
| 720 | } |
| 721 | |
| 722 | /** |
| 723 | * scond_broadcast: |
| 724 | * @cond : pointer to condition variable object |
| 725 | * |
| 726 | * Broadcast a condition. Unblocks all threads currently blocked |
| 727 | * on the specified condition variable @cond. |
| 728 | **/ |
| 729 | int scond_broadcast(scond_t *cond) |
| 730 | { |
| 731 | #ifdef USE_WIN32_THREADS |
| 732 | /* Remember, we currently have mutex */ |
| 733 | if (cond->waiters != 0) |
| 734 | { |
| 735 | /* Awaken everything which is currently queued up */ |
| 736 | if (cond->wakens == 0) |
| 737 | SetEvent(cond->event); |
| 738 | cond->wakens = cond->waiters; |
| 739 | |
| 740 | /* Since there is now at least one pending waken, the potato must be in play */ |
| 741 | SetEvent(cond->hot_potato); |
| 742 | } |
| 743 | return 0; |
| 744 | #else |
| 745 | return pthread_cond_broadcast(&cond->cond); |
| 746 | #endif |
| 747 | } |
| 748 | |
| 749 | /** |
| 750 | * scond_signal: |
| 751 | * @cond : pointer to condition variable object |
| 752 | * |
| 753 | * Signal a condition. Unblocks at least one of the threads currently blocked |
| 754 | * on the specified condition variable @cond. |
| 755 | **/ |
| 756 | void scond_signal(scond_t *cond) |
| 757 | { |
| 758 | #ifdef USE_WIN32_THREADS |
| 759 | |
| 760 | /* Unfortunately, pthread_cond_signal does not require that the |
| 761 | * lock be held in advance */ |
| 762 | /* To avoid stomping on the condvar from other threads, we need |
| 763 | * to control access to it with this */ |
| 764 | EnterCriticalSection(&cond->cs); |
| 765 | |
| 766 | /* remember: we currently have mutex */ |
| 767 | if (cond->waiters == 0) |
| 768 | { |
| 769 | LeaveCriticalSection(&cond->cs); |
| 770 | return; |
| 771 | } |
| 772 | |
| 773 | /* wake up the next thing in the queue */ |
| 774 | if (cond->wakens == 0) |
| 775 | SetEvent(cond->event); |
| 776 | |
| 777 | cond->wakens++; |
| 778 | |
| 779 | /* The data structure is done being modified.. I think we can leave the CS now. |
| 780 | * This would prevent some other thread from receiving the hot potato and then |
| 781 | * immediately stalling for the critical section. |
| 782 | * But remember, we were trying to replicate a semantic where this entire |
| 783 | * scond_signal call was controlled (by the user) by a lock. |
| 784 | * So in case there's trouble with this, we can move it after SetEvent() */ |
| 785 | LeaveCriticalSection(&cond->cs); |
| 786 | |
| 787 | /* Since there is now at least one pending waken, the potato must be in play */ |
| 788 | SetEvent(cond->hot_potato); |
| 789 | |
| 790 | #else |
| 791 | pthread_cond_signal(&cond->cond); |
| 792 | #endif |
| 793 | } |
| 794 | |
| 795 | /** |
| 796 | * scond_wait_timeout: |
| 797 | * @cond : pointer to condition variable object |
| 798 | * @lock : pointer to mutex object |
| 799 | * @timeout_us : timeout (in microseconds) |
| 800 | * |
| 801 | * Try to block on a condition variable (i.e. wait on a condition) until |
| 802 | * @timeout_us elapses. |
| 803 | * |
| 804 | * Returns: false (0) if timeout elapses before condition variable is |
| 805 | * signaled or broadcast, otherwise true (1). |
| 806 | **/ |
| 807 | bool scond_wait_timeout(scond_t *cond, slock_t *lock, int64_t timeout_us) |
| 808 | { |
| 809 | #ifdef USE_WIN32_THREADS |
| 810 | /* How to convert a microsecond (us) timeout to millisecond (ms)? |
| 811 | * |
| 812 | * Someone asking for a 0 timeout clearly wants immediate timeout. |
| 813 | * Someone asking for a 1 timeout clearly wants an actual timeout |
| 814 | * of the minimum length */ |
| 815 | /* The implementation of a 0 timeout here with pthreads is sketchy. |
| 816 | * It isn't clear what happens if pthread_cond_timedwait is called with NOW. |
| 817 | * Moreover, it is possible that this thread gets pre-empted after the |
| 818 | * clock_gettime but before the pthread_cond_timedwait. |
| 819 | * In order to help smoke out problems caused by this strange usage, |
| 820 | * let's treat a 0 timeout as always timing out. |
| 821 | */ |
| 822 | if (timeout_us == 0) |
| 823 | return false; |
| 824 | else if (timeout_us < 1000) |
| 825 | return _scond_wait_win32(cond, lock, 1); |
| 826 | /* Someone asking for 1000 or 1001 timeout shouldn't |
| 827 | * accidentally get 2ms. */ |
| 828 | return _scond_wait_win32(cond, lock, timeout_us / 1000); |
| 829 | #else |
| 830 | int64_t seconds, remainder; |
| 831 | struct timespec now; |
| 832 | #ifdef __MACH__ |
| 833 | /* OSX doesn't have clock_gettime. */ |
| 834 | clock_serv_t cclock; |
| 835 | mach_timespec_t mts; |
| 836 | host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock); |
| 837 | clock_get_time(cclock, &mts); |
| 838 | mach_port_deallocate(mach_task_self(), cclock); |
| 839 | now.tv_sec = mts.tv_sec; |
| 840 | now.tv_nsec = mts.tv_nsec; |
| 841 | #elif !defined(__PSL1GHT__) && defined(__PS3__) |
| 842 | sys_time_sec_t s; |
| 843 | sys_time_nsec_t n; |
| 844 | sys_time_get_current_time(&s, &n); |
| 845 | now.tv_sec = s; |
| 846 | now.tv_nsec = n; |
| 847 | #elif defined(PS2) |
| 848 | int tickms = ps2_clock(); |
| 849 | now.tv_sec = tickms / 1000; |
| 850 | now.tv_nsec = tickms * 1000; |
| 851 | #elif !defined(DINGUX_BETA) && (defined(__mips__) || defined(VITA) || defined(_3DS)) |
| 852 | struct timeval tm; |
| 853 | gettimeofday(&tm, NULL); |
| 854 | now.tv_sec = tm.tv_sec; |
| 855 | now.tv_nsec = tm.tv_usec * 1000; |
| 856 | #elif defined(RETRO_WIN32_USE_PTHREADS) |
| 857 | _ftime64_s(&now); |
| 858 | #elif defined(GEKKO) |
| 859 | /* Avoid gettimeofday due to it being reported to be broken */ |
| 860 | const uint64_t tickms = gettime() / TB_TIMER_CLOCK; |
| 861 | now.tv_sec = tickms / 1000; |
| 862 | now.tv_nsec = tickms * 1000; |
| 863 | #else |
| 864 | clock_gettime(CLOCK_REALTIME, &now); |
| 865 | #endif |
| 866 | |
| 867 | seconds = timeout_us / INT64_C(1000000); |
| 868 | remainder = timeout_us % INT64_C(1000000); |
| 869 | |
| 870 | now.tv_sec += seconds; |
| 871 | now.tv_nsec += remainder * INT64_C(1000); |
| 872 | |
| 873 | if (now.tv_nsec > 1000000000) |
| 874 | { |
| 875 | now.tv_nsec -= 1000000000; |
| 876 | now.tv_sec += 1; |
| 877 | } |
| 878 | |
| 879 | return (pthread_cond_timedwait(&cond->cond, &lock->lock, &now) == 0); |
| 880 | #endif |
| 881 | } |
| 882 | |
| 883 | #ifdef HAVE_THREAD_STORAGE |
| 884 | bool sthread_tls_create(sthread_tls_t *tls) |
| 885 | { |
| 886 | #ifdef USE_WIN32_THREADS |
| 887 | return (*tls = TlsAlloc()) != TLS_OUT_OF_INDEXES; |
| 888 | #else |
| 889 | return pthread_key_create((pthread_key_t*)tls, NULL) == 0; |
| 890 | #endif |
| 891 | } |
| 892 | |
| 893 | bool sthread_tls_delete(sthread_tls_t *tls) |
| 894 | { |
| 895 | #ifdef USE_WIN32_THREADS |
| 896 | return TlsFree(*tls) != 0; |
| 897 | #else |
| 898 | return pthread_key_delete(*tls) == 0; |
| 899 | #endif |
| 900 | } |
| 901 | |
| 902 | void *sthread_tls_get(sthread_tls_t *tls) |
| 903 | { |
| 904 | #ifdef USE_WIN32_THREADS |
| 905 | return TlsGetValue(*tls); |
| 906 | #else |
| 907 | return pthread_getspecific(*tls); |
| 908 | #endif |
| 909 | } |
| 910 | |
| 911 | bool sthread_tls_set(sthread_tls_t *tls, const void *data) |
| 912 | { |
| 913 | #ifdef USE_WIN32_THREADS |
| 914 | return TlsSetValue(*tls, (void*)data) != 0; |
| 915 | #else |
| 916 | return pthread_setspecific(*tls, data) == 0; |
| 917 | #endif |
| 918 | } |
| 919 | #endif |
| 920 | |
| 921 | uintptr_t sthread_get_thread_id(sthread_t *thread) |
| 922 | { |
| 923 | if (thread) |
| 924 | return (uintptr_t)thread->id; |
| 925 | return 0; |
| 926 | } |
| 927 | |
| 928 | uintptr_t sthread_get_current_thread_id(void) |
| 929 | { |
| 930 | #ifdef USE_WIN32_THREADS |
| 931 | return (uintptr_t)GetCurrentThreadId(); |
| 932 | #else |
| 933 | return (uintptr_t)pthread_self(); |
| 934 | #endif |
| 935 | } |