xref: /haiku/src/kits/media/MediaEventLooper.cpp (revision 71cc4d49983c5897e72bfd8b2eb1b6b6d704d0d7)
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 
221 	// While there are no events or it is not time for the earliest event,
222 	// process messages using WaitForMessages. Whenever this funtion times out,
223 	// we need to handle the next event
224 
225 	fSchedulingLatency = estimate_max_scheduling_latency(fControlThread);
226 	while (true) {
227 		if (RunState() == B_QUITTING)
228 			return;
229 
230 		err = WaitForMessage(waitUntil);
231 		if (err == B_TIMED_OUT
232 				|| err == B_WOULD_BLOCK) {
233 			media_timed_event event;
234 			if (hasEvent)
235 				err = fEventQueue.RemoveFirstEvent(&event);
236 			else if (hasRealtime)
237 				err = fRealTimeQueue.RemoveFirstEvent(&event);
238 
239 			if (err == B_OK) {
240 				bigtime_t lateness = waitUntil - TimeSource()->RealTime();
241 				if (lateness < 0)
242 					lateness = 0;
243 
244 				DispatchEvent(&event, lateness, hasRealtime);
245 			}
246 		} else if (err != B_OK)
247 			return;
248 
249 		// BMediaEventLooper compensates your performance time by adding
250 		// the event latency (see SetEventLatency()) and the scheduling
251 		// latency (or, for real-time events, only the scheduling latency).
252 
253 		hasRealtime = fRealTimeQueue.HasEvents();
254 		hasEvent = fEventQueue.HasEvents();
255 
256 		if (hasEvent) {
257 			waitUntil = TimeSource()->RealTimeFor(
258 				fEventQueue.FirstEventTime(),
259 				fEventLatency + fSchedulingLatency);
260 		} else if (!hasRealtime) {
261 			waitUntil = B_INFINITE_TIMEOUT;
262 			continue;
263 		}
264 
265 		if (hasRealtime) {
266 			bigtime_t realtimeWait = fRealTimeQueue.FirstEventTime()
267 				- fSchedulingLatency;
268 
269 			if (!hasEvent || realtimeWait <= waitUntil) {
270 				waitUntil = realtimeWait;
271 				hasEvent = false;
272 			} else
273 				hasRealtime = false;
274 		}
275 	}
276 }
277 
278 
279 thread_id
280 BMediaEventLooper::ControlThread()
281 {
282 	CALLED();
283 	return fControlThread;
284 }
285 
286 /*************************************************************
287  * protected BMediaEventLooper
288  *************************************************************/
289 
290 
291 BTimedEventQueue *
292 BMediaEventLooper::EventQueue()
293 {
294 	CALLED();
295 	return &fEventQueue;
296 }
297 
298 
299 BTimedEventQueue *
300 BMediaEventLooper::RealTimeQueue()
301 {
302 	CALLED();
303 	return &fRealTimeQueue;
304 }
305 
306 
307 int32
308 BMediaEventLooper::Priority() const
309 {
310 	CALLED();
311 	return fCurrentPriority;
312 }
313 
314 
315 int32
316 BMediaEventLooper::RunState() const
317 {
318 	PRINT(6, "CALLED BMediaEventLooper::RunState()\n");
319 	return fRunState;
320 }
321 
322 
323 bigtime_t
324 BMediaEventLooper::EventLatency() const
325 {
326 	CALLED();
327 	return fEventLatency;
328 }
329 
330 
331 bigtime_t
332 BMediaEventLooper::BufferDuration() const
333 {
334 	CALLED();
335 	return fBufferDuration;
336 }
337 
338 
339 bigtime_t
340 BMediaEventLooper::SchedulingLatency() const
341 {
342 	CALLED();
343 	return fSchedulingLatency;
344 }
345 
346 
347 status_t
348 BMediaEventLooper::SetPriority(int32 priority)
349 {
350 	CALLED();
351 
352 	// clamp to a valid value
353 	if (priority < 5)
354 		priority = 5;
355 
356 	if (priority > 120)
357 		priority = 120;
358 
359 	fSetPriority = priority;
360 	fCurrentPriority = (RunMode() == B_OFFLINE) ? min_c(B_NORMAL_PRIORITY, fSetPriority) : fSetPriority;
361 
362 	if (fControlThread > 0) {
363 		set_thread_priority(fControlThread, fCurrentPriority);
364 		fSchedulingLatency = estimate_max_scheduling_latency(fControlThread);
365 		printf("BMediaEventLooper: SchedulingLatency is %" B_PRId64 "\n",
366 			fSchedulingLatency);
367 	}
368 
369 	return B_OK;
370 }
371 
372 
373 void
374 BMediaEventLooper::SetRunState(run_state state)
375 {
376 	CALLED();
377 
378 	// don't allow run state changes while quitting,
379 	// also needed for correct terminating of the ControlLoop()
380 	if (fRunState == B_QUITTING && state != B_TERMINATED)
381 		return;
382 
383 	fRunState = state;
384 }
385 
386 
387 void
388 BMediaEventLooper::SetEventLatency(bigtime_t latency)
389 {
390 	CALLED();
391 	// clamp to a valid value
392 	if (latency < 0)
393 		latency = 0;
394 
395 	fEventLatency = latency;
396 	write_port_etc(ControlPort(), GENERAL_PURPOSE_WAKEUP, 0, 0, B_TIMEOUT, 0);
397 }
398 
399 
400 void
401 BMediaEventLooper::SetBufferDuration(bigtime_t duration)
402 {
403 	CALLED();
404 	fBufferDuration = duration;
405 }
406 
407 
408 void
409 BMediaEventLooper::SetOfflineTime(bigtime_t offTime)
410 {
411 	CALLED();
412 	fOfflineTime = offTime;
413 }
414 
415 
416 void
417 BMediaEventLooper::Run()
418 {
419 	CALLED();
420 
421 	if (fControlThread != -1)
422 		return; // thread already running
423 
424 	// until now, the run state is B_UNREGISTERED, but we need to start in B_STOPPED state.
425 	SetRunState(B_STOPPED);
426 
427 	char threadName[32];
428 	sprintf(threadName, "%.20s control", Name());
429 	fControlThread = spawn_thread(_ControlThreadStart, threadName, fCurrentPriority, this);
430 	resume_thread(fControlThread);
431 
432 	// get latency information
433 	fSchedulingLatency = estimate_max_scheduling_latency(fControlThread);
434 }
435 
436 
437 void
438 BMediaEventLooper::Quit()
439 {
440 	CALLED();
441 
442 	if (fRunState == B_TERMINATED)
443 		return;
444 
445 	SetRunState(B_QUITTING);
446 	close_port(ControlPort());
447 	if (fControlThread != -1) {
448 		status_t err;
449 		wait_for_thread(fControlThread, &err);
450 		fControlThread = -1;
451 	}
452 	SetRunState(B_TERMINATED);
453 }
454 
455 
456 void
457 BMediaEventLooper::DispatchEvent(const media_timed_event *event,
458 								 bigtime_t lateness,
459 								 bool realTimeEvent)
460 {
461 	PRINT(6, "CALLED BMediaEventLooper::DispatchEvent()\n");
462 
463 	HandleEvent(event, lateness, realTimeEvent);
464 
465 	switch (event->type) {
466 		case BTimedEventQueue::B_START:
467 			SetRunState(B_STARTED);
468 			break;
469 
470 		case BTimedEventQueue::B_STOP:
471 			SetRunState(B_STOPPED);
472 			break;
473 
474 		case BTimedEventQueue::B_SEEK:
475 			/* nothing */
476 			break;
477 
478 		case BTimedEventQueue::B_WARP:
479 			/* nothing */
480 			break;
481 
482 		case BTimedEventQueue::B_TIMER:
483 			TimerExpired(event->event_time, event->data);
484 			break;
485 
486 		default:
487 			break;
488 	}
489 
490 	_DispatchCleanUp(event);
491 }
492 
493 /*************************************************************
494  * private BMediaEventLooper
495  *************************************************************/
496 
497 
498 /* static */ int32
499 BMediaEventLooper::_ControlThreadStart(void *arg)
500 {
501 	CALLED();
502 	((BMediaEventLooper *)arg)->SetRunState(B_STOPPED);
503 	((BMediaEventLooper *)arg)->ControlLoop();
504 	((BMediaEventLooper *)arg)->SetRunState(B_QUITTING);
505 	return 0;
506 }
507 
508 
509 /* static */ void
510 BMediaEventLooper::_CleanUpEntry(const media_timed_event *event,
511 								 void *context)
512 {
513 	PRINT(6, "CALLED BMediaEventLooper::_CleanUpEntry()\n");
514 	((BMediaEventLooper *)context)->_DispatchCleanUp(event);
515 }
516 
517 
518 void
519 BMediaEventLooper::_DispatchCleanUp(const media_timed_event *event)
520 {
521 	PRINT(6, "CALLED BMediaEventLooper::_DispatchCleanUp()\n");
522 
523 	// this function to clean up after custom events you've created
524 	if (event->cleanup >= BTimedEventQueue::B_USER_CLEANUP)
525 		CleanUpEvent(event);
526 }
527 
528 /*
529 // unimplemented
530 BMediaEventLooper::BMediaEventLooper(const BMediaEventLooper &)
531 BMediaEventLooper &BMediaEventLooper::operator=(const BMediaEventLooper &)
532 */
533 
534 /*************************************************************
535  * protected BMediaEventLooper
536  *************************************************************/
537 
538 
539 status_t
540 BMediaEventLooper::DeleteHook(BMediaNode *node)
541 {
542 	CALLED();
543 	// this is the DeleteHook that gets called by the media server
544 	// before the media node is deleted
545 	Quit();
546 	return BMediaNode::DeleteHook(node);
547 }
548 
549 /*************************************************************
550  * private BMediaEventLooper
551  *************************************************************/
552 
553 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_0(int32 arg,...) { return B_ERROR; }
554 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_1(int32 arg,...) { return B_ERROR; }
555 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_2(int32 arg,...) { return B_ERROR; }
556 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_3(int32 arg,...) { return B_ERROR; }
557 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_4(int32 arg,...) { return B_ERROR; }
558 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_5(int32 arg,...) { return B_ERROR; }
559 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_6(int32 arg,...) { return B_ERROR; }
560 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_7(int32 arg,...) { return B_ERROR; }
561 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_8(int32 arg,...) { return B_ERROR; }
562 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_9(int32 arg,...) { return B_ERROR; }
563 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_10(int32 arg,...) { return B_ERROR; }
564 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_11(int32 arg,...) { return B_ERROR; }
565 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_12(int32 arg,...) { return B_ERROR; }
566 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_13(int32 arg,...) { return B_ERROR; }
567 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_14(int32 arg,...) { return B_ERROR; }
568 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_15(int32 arg,...) { return B_ERROR; }
569 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_16(int32 arg,...) { return B_ERROR; }
570 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_17(int32 arg,...) { return B_ERROR; }
571 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_18(int32 arg,...) { return B_ERROR; }
572 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_19(int32 arg,...) { return B_ERROR; }
573 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_20(int32 arg,...) { return B_ERROR; }
574 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_21(int32 arg,...) { return B_ERROR; }
575 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_22(int32 arg,...) { return B_ERROR; }
576 status_t BMediaEventLooper::_Reserved_BMediaEventLooper_23(int32 arg,...) { return B_ERROR; }
577 
578