1 /* 2 * Copyright (c) 2015 Dario Casalinuovo <b.vitruvio@gmail.com> 3 * Copyright (c) 2002, 2003 Marcus Overhagen <Marcus@Overhagen.de> 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining 6 * a copy of this software and associated documentation files or portions 7 * thereof (the "Software"), to deal in the Software without restriction, 8 * including without limitation the rights to use, copy, modify, merge, 9 * publish, distribute, sublicense, and/or sell copies of the Software, 10 * and to permit persons to whom the Software is furnished to do so, subject 11 * to the following conditions: 12 * 13 * * Redistributions of source code must retain the above copyright notice, 14 * this list of conditions and the following disclaimer. 15 * 16 * * Redistributions in binary form must reproduce the above copyright notice 17 * in the binary, as well as this list of conditions and the following 18 * disclaimer in the documentation and/or other materials provided with 19 * the distribution. 20 * 21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 22 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 24 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 25 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 26 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 27 * THE SOFTWARE. 28 * 29 */ 30 31 #include <MediaEventLooper.h> 32 #include <TimeSource.h> 33 #include <scheduler.h> 34 #include <Buffer.h> 35 #include <ServerInterface.h> 36 #include "debug.h" 37 38 /************************************************************* 39 * protected BMediaEventLooper 40 *************************************************************/ 41 42 /* virtual */ 43 BMediaEventLooper::~BMediaEventLooper() 44 { 45 CALLED(); 46 47 // don't call Quit(); here, except if the user was stupid 48 if (fControlThread != -1) { 49 printf("You MUST call BMediaEventLooper::Quit() in your destructor!\n"); 50 Quit(); 51 } 52 } 53 54 /* explicit */ 55 BMediaEventLooper::BMediaEventLooper(uint32 apiVersion) : 56 BMediaNode("called by BMediaEventLooper"), 57 fControlThread(-1), 58 fCurrentPriority(B_URGENT_PRIORITY), 59 fSetPriority(B_URGENT_PRIORITY), 60 fRunState(B_UNREGISTERED), 61 fEventLatency(0), 62 fSchedulingLatency(0), 63 fBufferDuration(0), 64 fOfflineTime(0), 65 fApiVersion(apiVersion) 66 { 67 CALLED(); 68 fEventQueue.SetCleanupHook(BMediaEventLooper::_CleanUpEntry, this); 69 fRealTimeQueue.SetCleanupHook(BMediaEventLooper::_CleanUpEntry, this); 70 } 71 72 /* virtual */ void 73 BMediaEventLooper::NodeRegistered() 74 { 75 CALLED(); 76 // Calling Run() should be done by the derived class, 77 // at least that's how it is documented by the BeBook. 78 // It appears that BeOS R5 called it here. Calling Run() 79 // twice doesn't hurt, and some nodes need it to be called here. 80 Run(); 81 } 82 83 84 /* virtual */ void 85 BMediaEventLooper::Start(bigtime_t performance_time) 86 { 87 CALLED(); 88 // This hook function is called when a node is started 89 // by a call to the BMediaRoster. The specified 90 // performanceTime, the time at which the node 91 // should start running, may be in the future. 92 fEventQueue.AddEvent(media_timed_event(performance_time, BTimedEventQueue::B_START)); 93 } 94 95 96 /* virtual */ void 97 BMediaEventLooper::Stop(bigtime_t performance_time, 98 bool immediate) 99 { 100 CALLED(); 101 // This hook function is called when a node is stopped 102 // by a call to the BMediaRoster. The specified performanceTime, 103 // the time at which the node should stop, may be in the future. 104 // If immediate is true, your node should ignore the performanceTime 105 // value and synchronously stop performance. When Stop() returns, 106 // you're promising not to write into any BBuffers you may have 107 // received from your downstream consumers, and you promise not 108 // to send any more buffers until Start() is called again. 109 110 if (immediate) { 111 // always be sure to add to the front of the queue so we can make sure it is 112 // handled before any buffers are sent! 113 performance_time = 0; 114 } 115 fEventQueue.AddEvent(media_timed_event(performance_time, BTimedEventQueue::B_STOP)); 116 } 117 118 119 /* virtual */ void 120 BMediaEventLooper::Seek(bigtime_t media_time, 121 bigtime_t performance_time) 122 { 123 CALLED(); 124 // This hook function is called when a node is asked to seek to 125 // the specified mediaTime by a call to the BMediaRoster. 126 // The specified performanceTime, the time at which the node 127 // should begin the seek operation, may be in the future. 128 fEventQueue.AddEvent(media_timed_event(performance_time, BTimedEventQueue::B_SEEK, NULL, 129 BTimedEventQueue::B_NO_CLEANUP, 0, media_time, NULL)); 130 } 131 132 133 /* virtual */ void 134 BMediaEventLooper::TimeWarp(bigtime_t at_real_time, 135 bigtime_t to_performance_time) 136 { 137 CALLED(); 138 // This hook function is called when the time source to which the 139 // node is slaved is repositioned (via a seek operation) such that 140 // there will be a sudden jump in the performance time progression 141 // as seen by the node. The to_performance_time argument indicates 142 // the new performance time; the change should occur at the real 143 // time specified by the at_real_time argument. 144 145 // place in the realtime queue 146 fRealTimeQueue.AddEvent(media_timed_event(at_real_time, BTimedEventQueue::B_WARP, 147 NULL, BTimedEventQueue::B_NO_CLEANUP, 0, to_performance_time, NULL)); 148 149 // BeBook: Your implementation of TimeWarp() should call through to BMediaNode::TimeWarp() 150 // BeBook: as well as all other inherited forms of TimeWarp() 151 // XXX should we do this here? 152 BMediaNode::TimeWarp(at_real_time, to_performance_time); 153 } 154 155 156 /* virtual */ status_t 157 BMediaEventLooper::AddTimer(bigtime_t at_performance_time, 158 int32 cookie) 159 { 160 CALLED(); 161 162 media_timed_event event(at_performance_time, 163 BTimedEventQueue::B_TIMER, NULL, 164 BTimedEventQueue::B_EXPIRE_TIMER); 165 event.data = cookie; 166 return EventQueue()->AddEvent(event); 167 } 168 169 170 /* virtual */ void 171 BMediaEventLooper::SetRunMode(run_mode mode) 172 { 173 CALLED(); 174 // The SetRunMode() hook function is called when someone requests that your node's run mode be changed. 175 176 // bump or reduce priority when switching from/to offline run mode 177 int32 priority; 178 priority = (mode == B_OFFLINE) ? min_c(B_NORMAL_PRIORITY, fSetPriority) : fSetPriority; 179 if (priority != fCurrentPriority) { 180 fCurrentPriority = priority; 181 if (fControlThread > 0) { 182 set_thread_priority(fControlThread, fCurrentPriority); 183 fSchedulingLatency = estimate_max_scheduling_latency(fControlThread); 184 printf("BMediaEventLooper: SchedulingLatency is %" B_PRId64 "\n", 185 fSchedulingLatency); 186 } 187 } 188 189 BMediaNode::SetRunMode(mode); 190 } 191 192 193 /* virtual */ void 194 BMediaEventLooper::CleanUpEvent(const media_timed_event *event) 195 { 196 CALLED(); 197 // Implement this function to clean up after custom events you've created 198 // and added to your queue. It's called when a custom event is removed from 199 // the queue, to let you handle any special tidying-up that the event might require. 200 } 201 202 203 /* virtual */ bigtime_t 204 BMediaEventLooper::OfflineTime() 205 { 206 CALLED(); 207 return fOfflineTime; 208 } 209 210 211 /* virtual */ void 212 BMediaEventLooper::ControlLoop() 213 { 214 CALLED(); 215 216 status_t err; 217 bigtime_t waitUntil = B_INFINITE_TIMEOUT; 218 bool hasRealtime = false; 219 bool hasEvent = false; 220 bool hasBooted = false; 221 222 // While there are no events or it is not time for the earliest event, 223 // process messages using WaitForMessages. Whenever this funtion times out, 224 // we need to handle the next event 225 226 fSchedulingLatency = estimate_max_scheduling_latency(fControlThread); 227 while (true) { 228 if (RunState() == B_QUITTING) 229 return; 230 231 err = WaitForMessage(waitUntil); 232 if (err == B_TIMED_OUT 233 || err == B_WOULD_BLOCK) { 234 // NOTE: The reference for doing the lateness calculus this way can 235 // be found in the BeBook article "A BMediaEventLooper Example". 236 // The value which we are going to calculate, is referred there as 237 // 'lateness'. 238 media_timed_event event; 239 if (hasEvent) 240 err = fEventQueue.RemoveFirstEvent(&event); 241 else if (hasRealtime) 242 err = fRealTimeQueue.RemoveFirstEvent(&event); 243 244 if (err == B_OK) { 245 // We are going to do this calculus in real time 246 // because otherwise we could get erroneous values. 247 // This calculus allow us to detect both early and late 248 // buffers, this is the meaning of the lateness concept. 249 bigtime_t lateness = waitUntil - TimeSource()->RealTime(); 250 DispatchEvent(&event, -lateness, hasRealtime); 251 } 252 } else if (err != B_OK) 253 return; 254 255 // BMediaEventLooper compensates your performance time by adding 256 // the event latency (see SetEventLatency()) and the scheduling 257 // latency (or, for real-time events, only the scheduling latency). 258 259 hasRealtime = fRealTimeQueue.HasEvents(); 260 hasEvent = fEventQueue.HasEvents(); 261 262 if (hasEvent) { 263 waitUntil = TimeSource()->RealTimeFor( 264 fEventQueue.FirstEventTime(), 265 fEventLatency + fSchedulingLatency); 266 267 // The first event we handle will have 268 // a negative startup wait. In this case 269 // we just check the port and let the 270 // first event to be executed just now. 271 if (!hasBooted && waitUntil < 0) { 272 waitUntil = 0; 273 hasBooted = true; 274 } 275 } else if (!hasRealtime) { 276 waitUntil = B_INFINITE_TIMEOUT; 277 continue; 278 } 279 280 if (hasRealtime) { 281 bigtime_t realtimeWait = fRealTimeQueue.FirstEventTime() 282 - fSchedulingLatency; 283 284 if (!hasEvent || realtimeWait <= waitUntil) { 285 waitUntil = realtimeWait; 286 hasEvent = false; 287 } else 288 hasRealtime = false; 289 } 290 } 291 } 292 293 294 thread_id 295 BMediaEventLooper::ControlThread() 296 { 297 CALLED(); 298 return fControlThread; 299 } 300 301 /************************************************************* 302 * protected BMediaEventLooper 303 *************************************************************/ 304 305 306 BTimedEventQueue * 307 BMediaEventLooper::EventQueue() 308 { 309 CALLED(); 310 return &fEventQueue; 311 } 312 313 314 BTimedEventQueue * 315 BMediaEventLooper::RealTimeQueue() 316 { 317 CALLED(); 318 return &fRealTimeQueue; 319 } 320 321 322 int32 323 BMediaEventLooper::Priority() const 324 { 325 CALLED(); 326 return fCurrentPriority; 327 } 328 329 330 int32 331 BMediaEventLooper::RunState() const 332 { 333 PRINT(6, "CALLED BMediaEventLooper::RunState()\n"); 334 return fRunState; 335 } 336 337 338 bigtime_t 339 BMediaEventLooper::EventLatency() const 340 { 341 CALLED(); 342 return fEventLatency; 343 } 344 345 346 bigtime_t 347 BMediaEventLooper::BufferDuration() const 348 { 349 CALLED(); 350 return fBufferDuration; 351 } 352 353 354 bigtime_t 355 BMediaEventLooper::SchedulingLatency() const 356 { 357 CALLED(); 358 return fSchedulingLatency; 359 } 360 361 362 status_t 363 BMediaEventLooper::SetPriority(int32 priority) 364 { 365 CALLED(); 366 367 // clamp to a valid value 368 if (priority < 5) 369 priority = 5; 370 371 if (priority > 120) 372 priority = 120; 373 374 fSetPriority = priority; 375 fCurrentPriority = (RunMode() == B_OFFLINE) ? min_c(B_NORMAL_PRIORITY, fSetPriority) : fSetPriority; 376 377 if (fControlThread > 0) { 378 set_thread_priority(fControlThread, fCurrentPriority); 379 fSchedulingLatency = estimate_max_scheduling_latency(fControlThread); 380 printf("BMediaEventLooper: SchedulingLatency is %" B_PRId64 "\n", 381 fSchedulingLatency); 382 } 383 384 return B_OK; 385 } 386 387 388 void 389 BMediaEventLooper::SetRunState(run_state state) 390 { 391 CALLED(); 392 393 // don't allow run state changes while quitting, 394 // also needed for correct terminating of the ControlLoop() 395 if (fRunState == B_QUITTING && state != B_TERMINATED) 396 return; 397 398 fRunState = state; 399 } 400 401 402 void 403 BMediaEventLooper::SetEventLatency(bigtime_t latency) 404 { 405 CALLED(); 406 // clamp to a valid value 407 if (latency < 0) 408 latency = 0; 409 410 fEventLatency = latency; 411 write_port_etc(ControlPort(), GENERAL_PURPOSE_WAKEUP, 0, 0, B_TIMEOUT, 0); 412 } 413 414 415 void 416 BMediaEventLooper::SetBufferDuration(bigtime_t duration) 417 { 418 CALLED(); 419 fBufferDuration = duration; 420 } 421 422 423 void 424 BMediaEventLooper::SetOfflineTime(bigtime_t offTime) 425 { 426 CALLED(); 427 fOfflineTime = offTime; 428 } 429 430 431 void 432 BMediaEventLooper::Run() 433 { 434 CALLED(); 435 436 if (fControlThread != -1) 437 return; // thread already running 438 439 // until now, the run state is B_UNREGISTERED, but we need to start in B_STOPPED state. 440 SetRunState(B_STOPPED); 441 442 char threadName[32]; 443 sprintf(threadName, "%.20s control", Name()); 444 fControlThread = spawn_thread(_ControlThreadStart, threadName, fCurrentPriority, this); 445 resume_thread(fControlThread); 446 447 // get latency information 448 fSchedulingLatency = estimate_max_scheduling_latency(fControlThread); 449 } 450 451 452 void 453 BMediaEventLooper::Quit() 454 { 455 CALLED(); 456 457 if (fRunState == B_TERMINATED) 458 return; 459 460 SetRunState(B_QUITTING); 461 close_port(ControlPort()); 462 if (fControlThread != -1) { 463 status_t err; 464 wait_for_thread(fControlThread, &err); 465 fControlThread = -1; 466 } 467 SetRunState(B_TERMINATED); 468 } 469 470 471 void 472 BMediaEventLooper::DispatchEvent(const media_timed_event *event, 473 bigtime_t lateness, 474 bool realTimeEvent) 475 { 476 PRINT(6, "CALLED BMediaEventLooper::DispatchEvent()\n"); 477 478 HandleEvent(event, lateness, realTimeEvent); 479 480 switch (event->type) { 481 case BTimedEventQueue::B_START: 482 SetRunState(B_STARTED); 483 break; 484 485 case BTimedEventQueue::B_STOP: 486 SetRunState(B_STOPPED); 487 break; 488 489 case BTimedEventQueue::B_SEEK: 490 /* nothing */ 491 break; 492 493 case BTimedEventQueue::B_WARP: 494 /* nothing */ 495 break; 496 497 case BTimedEventQueue::B_TIMER: 498 TimerExpired(event->event_time, event->data); 499 break; 500 501 default: 502 break; 503 } 504 505 _DispatchCleanUp(event); 506 } 507 508 /************************************************************* 509 * private BMediaEventLooper 510 *************************************************************/ 511 512 513 /* static */ int32 514 BMediaEventLooper::_ControlThreadStart(void *arg) 515 { 516 CALLED(); 517 ((BMediaEventLooper *)arg)->SetRunState(B_STOPPED); 518 ((BMediaEventLooper *)arg)->ControlLoop(); 519 ((BMediaEventLooper *)arg)->SetRunState(B_QUITTING); 520 return 0; 521 } 522 523 524 /* static */ void 525 BMediaEventLooper::_CleanUpEntry(const media_timed_event *event, 526 void *context) 527 { 528 PRINT(6, "CALLED BMediaEventLooper::_CleanUpEntry()\n"); 529 ((BMediaEventLooper *)context)->_DispatchCleanUp(event); 530 } 531 532 533 void 534 BMediaEventLooper::_DispatchCleanUp(const media_timed_event *event) 535 { 536 PRINT(6, "CALLED BMediaEventLooper::_DispatchCleanUp()\n"); 537 538 // this function to clean up after custom events you've created 539 if (event->cleanup >= BTimedEventQueue::B_USER_CLEANUP) 540 CleanUpEvent(event); 541 } 542 543 /* 544 // unimplemented 545 BMediaEventLooper::BMediaEventLooper(const BMediaEventLooper &) 546 BMediaEventLooper &BMediaEventLooper::operator=(const BMediaEventLooper &) 547 */ 548 549 /************************************************************* 550 * protected BMediaEventLooper 551 *************************************************************/ 552 553 554 status_t 555 BMediaEventLooper::DeleteHook(BMediaNode *node) 556 { 557 CALLED(); 558 // this is the DeleteHook that gets called by the media server 559 // before the media node is deleted 560 Quit(); 561 return BMediaNode::DeleteHook(node); 562 } 563 564 /************************************************************* 565 * private BMediaEventLooper 566 *************************************************************/ 567 568 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_0(int32 arg,...) { return B_ERROR; } 569 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_1(int32 arg,...) { return B_ERROR; } 570 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_2(int32 arg,...) { return B_ERROR; } 571 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_3(int32 arg,...) { return B_ERROR; } 572 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_4(int32 arg,...) { return B_ERROR; } 573 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_5(int32 arg,...) { return B_ERROR; } 574 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_6(int32 arg,...) { return B_ERROR; } 575 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_7(int32 arg,...) { return B_ERROR; } 576 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_8(int32 arg,...) { return B_ERROR; } 577 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_9(int32 arg,...) { return B_ERROR; } 578 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_10(int32 arg,...) { return B_ERROR; } 579 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_11(int32 arg,...) { return B_ERROR; } 580 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_12(int32 arg,...) { return B_ERROR; } 581 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_13(int32 arg,...) { return B_ERROR; } 582 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_14(int32 arg,...) { return B_ERROR; } 583 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_15(int32 arg,...) { return B_ERROR; } 584 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_16(int32 arg,...) { return B_ERROR; } 585 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_17(int32 arg,...) { return B_ERROR; } 586 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_18(int32 arg,...) { return B_ERROR; } 587 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_19(int32 arg,...) { return B_ERROR; } 588 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_20(int32 arg,...) { return B_ERROR; } 589 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_21(int32 arg,...) { return B_ERROR; } 590 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_22(int32 arg,...) { return B_ERROR; } 591 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_23(int32 arg,...) { return B_ERROR; } 592 593