1 /* GStreamer
2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2004,2005 Wim Taymans <wim@fluendo.com>
4 *
5 * gstpipeline.c: Overall pipeline management element
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
21 */
23 /**
24 * SECTION:gstpipeline
25 * @short_description: Top-level bin with clocking and bus management
26 functionality.
27 * @see_also: #GstElement, #GstBin, #GstClock, #GstBus
28 *
29 * A #GstPipeline is a special #GstBin used as the toplevel container for
30 * the filter graph. The #GstPipeline will manage the selection and
31 * distribution of a global #GstClock as well as provide a #GstBus to the
32 * application. It will also implement a default behaviour for managing
33 * seek events (see gst_element_seek()).
34 *
35 * gst_pipeline_new() is used to create a pipeline. when you are done with
36 * the pipeline, use gst_object_unref() to free its resources including all
37 * added #GstElement objects (if not otherwise referenced).
38 *
39 * Elements are added and removed from the pipeline using the #GstBin
40 * methods like gst_bin_add() and gst_bin_remove() (see #GstBin).
41 *
42 * Before changing the state of the #GstPipeline (see #GstElement) a #GstBus
43 * can be retrieved with gst_pipeline_get_bus(). This bus can then be
44 * used to receive #GstMessage from the elements in the pipeline.
45 *
46 * By default, a #GstPipeline will automatically flush the pending #GstBus
47 * messages when going to the NULL state to ensure that no circular
48 * references exist when no messages are read from the #GstBus. This
49 * behaviour can be changed with gst_pipeline_set_auto_flush_bus().
50 *
51 * When the #GstPipeline performs the PAUSED to PLAYING state change it will
52 * select a clock for the elements. The clock selection algorithm will by
53 * default select a clock provided by an element that is most upstream
54 * (closest to the source). For live pipelines (ones that return
55 * #GST_STATE_CHANGE_NO_PREROLL from the gst_element_set_state() call) this
56 * will select the clock provided by the live source. For normal pipelines
57 * this will select a clock provided by the sinks (most likely the audio
58 * sink). If no element provides a clock, a default #GstSystemClock is used.
59 *
60 * The clock selection can be controlled with the gst_pipeline_use_clock()
61 * method, which will enforce a given clock on the pipeline. With
62 * gst_pipeline_auto_clock() the default clock selection algorithm can be
63 * restored.
64 *
65 * A #GstPipeline maintains a running time for the elements. The running
66 * time is defined as the difference between the current clock time and
67 * the base time. When the pipeline goes to READY or a flushing seek is
68 * performed on it, the running time is reset to 0. When the pipeline is
69 * set from PLAYING to PAUSED, the current clock time is sampled and used to
70 * configure the base time for the elements when the pipeline is set
71 * to PLAYING again. The effect is that the running time (as the difference
72 * between the clock time and the base time) will count how much time was spent
73 * in the PLAYING state. This default behaviour can be changed with the
74 * gst_element_set_start_time() method.
75 *
76 * When sending a flushing seek event to a GstPipeline (see
77 * gst_element_seek()), it will make sure that the pipeline is properly
78 * PAUSED and resumed as well as set the new running time to 0 when the
79 * seek succeeded.
80 *
81 * Last reviewed on 2009-05-29 (0.10.24)
82 */
84 #include "gst_private.h"
85 #include "gsterror.h"
86 #include "gst-i18n-lib.h"
88 #include "gstpipeline.h"
89 #include "gstinfo.h"
90 #include "gstsystemclock.h"
91 #include "gstutils.h"
93 GST_DEBUG_CATEGORY_STATIC (pipeline_debug);
94 #define GST_CAT_DEFAULT pipeline_debug
96 /* Pipeline signals and args */
97 enum
98 {
99 /* FILL ME */
100 LAST_SIGNAL
101 };
103 #define DEFAULT_DELAY 0
104 #define DEFAULT_AUTO_FLUSH_BUS TRUE
106 enum
107 {
108 PROP_0,
109 PROP_DELAY,
110 PROP_AUTO_FLUSH_BUS
111 };
113 #define GST_PIPELINE_GET_PRIVATE(obj) \
114 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PIPELINE, GstPipelinePrivate))
116 struct _GstPipelinePrivate
117 {
118 /* with LOCK */
119 gboolean auto_flush_bus;
121 /* when we need to update stream_time or clock when going back to
122 * PLAYING*/
123 GstClockTime last_start_time;
124 gboolean update_clock;
125 };
128 static void gst_pipeline_dispose (GObject * object);
129 static void gst_pipeline_set_property (GObject * object, guint prop_id,
130 const GValue * value, GParamSpec * pspec);
131 static void gst_pipeline_get_property (GObject * object, guint prop_id,
132 GValue * value, GParamSpec * pspec);
134 static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
135 static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
136 GstStateChange transition);
138 static void gst_pipeline_handle_message (GstBin * bin, GstMessage * message);
140 /* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
142 #define _do_init(type) \
143 { \
144 GST_DEBUG_CATEGORY_INIT (pipeline_debug, "pipeline", GST_DEBUG_BOLD, \
145 "debugging info for the 'pipeline' container element"); \
146 }
148 GST_BOILERPLATE_FULL (GstPipeline, gst_pipeline, GstBin, GST_TYPE_BIN,
149 _do_init);
151 static void
152 gst_pipeline_base_init (gpointer g_class)
153 {
154 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
156 gst_element_class_set_details_simple (gstelement_class, "Pipeline object",
157 "Generic/Bin",
158 "Complete pipeline object",
159 "Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
160 }
162 static void
163 gst_pipeline_class_init (GstPipelineClass * klass)
164 {
165 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
166 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
167 GstBinClass *gstbin_class = GST_BIN_CLASS (klass);
169 g_type_class_add_private (klass, sizeof (GstPipelinePrivate));
171 gobject_class->set_property = gst_pipeline_set_property;
172 gobject_class->get_property = gst_pipeline_get_property;
174 /**
175 * GstPipeline:delay
176 *
177 * The expected delay needed for elements to spin up to the
178 * PLAYING state expressed in nanoseconds.
179 * see gst_pipeline_set_delay() for more information on this option.
180 *
181 * Since: 0.10.5
182 **/
183 g_object_class_install_property (gobject_class, PROP_DELAY,
184 g_param_spec_uint64 ("delay", "Delay",
185 "Expected delay needed for elements "
186 "to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
187 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
189 /**
190 * GstPipeline:auto-flush-bus:
191 *
192 * Whether or not to automatically flush all messages on the
193 * pipeline's bus when going from READY to NULL state. Please see
194 * gst_pipeline_set_auto_flush_bus() for more information on this option.
195 *
196 * Since: 0.10.4
197 **/
198 g_object_class_install_property (gobject_class, PROP_AUTO_FLUSH_BUS,
199 g_param_spec_boolean ("auto-flush-bus", "Auto Flush Bus",
200 "Whether to automatically flush the pipeline's bus when going "
201 "from READY into NULL state", DEFAULT_AUTO_FLUSH_BUS,
202 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
204 gobject_class->dispose = gst_pipeline_dispose;
206 gstelement_class->change_state =
207 GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
208 gstelement_class->provide_clock =
209 GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
210 gstbin_class->handle_message =
211 GST_DEBUG_FUNCPTR (gst_pipeline_handle_message);
212 }
214 static void
215 gst_pipeline_init (GstPipeline * pipeline, GstPipelineClass * klass)
216 {
217 GstBus *bus;
219 pipeline->priv = GST_PIPELINE_GET_PRIVATE (pipeline);
221 /* set default property values */
222 pipeline->priv->auto_flush_bus = DEFAULT_AUTO_FLUSH_BUS;
223 pipeline->delay = DEFAULT_DELAY;
225 /* create and set a default bus */
226 bus = gst_bus_new ();
227 #if 0
228 /* FIXME, disabled for 0.10.5 release as it caused to many regressions */
229 /* Start our bus in flushing if appropriate */
230 if (pipeline->priv->auto_flush_bus)
231 gst_bus_set_flushing (bus, TRUE);
232 #endif
234 gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
235 GST_DEBUG_OBJECT (pipeline, "set bus %" GST_PTR_FORMAT " on pipeline", bus);
236 gst_object_unref (bus);
237 }
239 static void
240 gst_pipeline_dispose (GObject * object)
241 {
242 GstPipeline *pipeline = GST_PIPELINE (object);
243 GstClock **clock_p = &pipeline->fixed_clock;
245 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
247 /* clear and unref any fixed clock */
248 gst_object_replace ((GstObject **) clock_p, NULL);
250 G_OBJECT_CLASS (parent_class)->dispose (object);
251 }
253 static void
254 gst_pipeline_set_property (GObject * object, guint prop_id,
255 const GValue * value, GParamSpec * pspec)
256 {
257 GstPipeline *pipeline = GST_PIPELINE (object);
259 switch (prop_id) {
260 case PROP_DELAY:
261 gst_pipeline_set_delay (pipeline, g_value_get_uint64 (value));
262 break;
263 case PROP_AUTO_FLUSH_BUS:
264 gst_pipeline_set_auto_flush_bus (pipeline, g_value_get_boolean (value));
265 break;
266 default:
267 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
268 break;
269 }
270 }
272 static void
273 gst_pipeline_get_property (GObject * object, guint prop_id,
274 GValue * value, GParamSpec * pspec)
275 {
276 GstPipeline *pipeline = GST_PIPELINE (object);
278 switch (prop_id) {
279 case PROP_DELAY:
280 g_value_set_uint64 (value, gst_pipeline_get_delay (pipeline));
281 break;
282 case PROP_AUTO_FLUSH_BUS:
283 g_value_set_boolean (value, gst_pipeline_get_auto_flush_bus (pipeline));
284 break;
285 default:
286 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
287 break;
288 }
289 }
291 /* set the start_time to 0, this will cause us to select a new base_time and
292 * make the running_time start from 0 again. */
293 static void
294 reset_start_time (GstPipeline * pipeline)
295 {
296 GST_OBJECT_LOCK (pipeline);
297 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
298 GST_DEBUG_OBJECT (pipeline, "reset start_time to 0");
299 GST_ELEMENT_START_TIME (pipeline) = 0;
300 pipeline->priv->last_start_time = -1;
301 } else {
302 GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
303 }
304 GST_OBJECT_UNLOCK (pipeline);
305 }
307 /**
308 * gst_pipeline_new:
309 * @name: name of new pipeline
310 *
311 * Create a new pipeline with the given name.
312 *
313 * Returns: (transfer full): newly created GstPipeline
314 *
315 * MT safe.
316 */
317 GstElement *
318 gst_pipeline_new (const gchar * name)
319 {
320 return gst_element_factory_make ("pipeline", name);
321 }
323 /* takes a snapshot of the running_time of the pipeline and store this as the
324 * element start_time. This is the time we will set as the running_time of the
325 * pipeline when we go to PLAYING next. */
326 static void
327 pipeline_update_start_time (GstElement * element)
328 {
329 GstPipeline *pipeline = GST_PIPELINE_CAST (element);
330 GstClock *clock;
332 GST_OBJECT_LOCK (element);
333 if ((clock = element->clock)) {
334 GstClockTime now;
336 gst_object_ref (clock);
337 GST_OBJECT_UNLOCK (element);
339 /* calculate the time when we stopped */
340 now = gst_clock_get_time (clock);
341 gst_object_unref (clock);
343 GST_OBJECT_LOCK (element);
344 /* store the current running time */
345 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
346 if (now != GST_CLOCK_TIME_NONE)
347 GST_ELEMENT_START_TIME (pipeline) = now - element->base_time;
348 else
349 GST_WARNING_OBJECT (element,
350 "Clock %s returned invalid time, can't calculate "
351 "running_time when going to the PAUSED state",
352 GST_OBJECT_NAME (clock));
354 /* we went to PAUSED, when going to PLAYING select clock and new
355 * base_time */
356 pipeline->priv->update_clock = TRUE;
357 }
358 GST_DEBUG_OBJECT (element,
359 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
360 ", base_time %" GST_TIME_FORMAT,
361 GST_TIME_ARGS (GST_ELEMENT_START_TIME (pipeline)),
362 GST_TIME_ARGS (now), GST_TIME_ARGS (element->base_time));
363 }
364 GST_OBJECT_UNLOCK (element);
365 }
367 /* MT safe */
368 static GstStateChangeReturn
369 gst_pipeline_change_state (GstElement * element, GstStateChange transition)
370 {
371 GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
372 GstPipeline *pipeline = GST_PIPELINE_CAST (element);
373 GstClock *clock;
375 switch (transition) {
376 case GST_STATE_CHANGE_NULL_TO_READY:
377 GST_OBJECT_LOCK (element);
378 if (element->bus)
379 gst_bus_set_flushing (element->bus, FALSE);
380 GST_OBJECT_UNLOCK (element);
381 break;
382 case GST_STATE_CHANGE_READY_TO_PAUSED:
383 GST_OBJECT_LOCK (element);
384 pipeline->priv->update_clock = TRUE;
385 GST_OBJECT_UNLOCK (element);
386 break;
387 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
388 {
389 GstClockTime now, start_time, last_start_time, delay;
390 gboolean update_clock;
391 GstClock *cur_clock;
393 GST_DEBUG_OBJECT (element, "selecting clock and base_time");
395 GST_OBJECT_LOCK (element);
396 cur_clock = element->clock;
397 if (cur_clock)
398 gst_object_ref (cur_clock);
399 /* get the desired running_time of the first buffer aka the start_time */
400 start_time = GST_ELEMENT_START_TIME (pipeline);
401 last_start_time = pipeline->priv->last_start_time;
402 pipeline->priv->last_start_time = start_time;
403 /* see if we need to update the clock */
404 update_clock = pipeline->priv->update_clock;
405 pipeline->priv->update_clock = FALSE;
406 delay = pipeline->delay;
407 GST_OBJECT_UNLOCK (element);
409 /* running time changed, either with a PAUSED or a flush, we need to check
410 * if there is a new clock & update the base time */
411 if (update_clock || last_start_time != start_time) {
412 GST_DEBUG_OBJECT (pipeline, "Need to update start_time");
414 /* when going to PLAYING, select a clock when needed. If we just got
415 * flushed, we don't reselect the clock. */
416 if (update_clock) {
417 GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
418 clock = gst_element_provide_clock (element);
419 } else {
420 GST_DEBUG_OBJECT (pipeline,
421 "Don't need to update clock, using old clock.");
422 clock = gst_object_ref (cur_clock);
423 }
425 if (clock) {
426 now = gst_clock_get_time (clock);
427 } else {
428 GST_DEBUG_OBJECT (pipeline, "no clock, using base time of NONE");
429 now = GST_CLOCK_TIME_NONE;
430 }
432 if (clock != cur_clock) {
433 /* now distribute the clock (which could be NULL). If some
434 * element refuses the clock, this will return FALSE and
435 * we effectively fail the state change. */
436 if (!gst_element_set_clock (element, clock))
437 goto invalid_clock;
439 /* if we selected and distributed a new clock, let the app
440 * know about it */
441 gst_element_post_message (element,
442 gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
443 }
445 if (clock)
446 gst_object_unref (clock);
448 if (start_time != GST_CLOCK_TIME_NONE && now != GST_CLOCK_TIME_NONE) {
449 GstClockTime new_base_time = now - start_time + delay;
450 GST_DEBUG_OBJECT (element,
451 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
452 ", base_time %" GST_TIME_FORMAT,
453 GST_TIME_ARGS (start_time), GST_TIME_ARGS (now),
454 GST_TIME_ARGS (new_base_time));
456 gst_element_set_base_time (element, new_base_time);
457 } else {
458 GST_DEBUG_OBJECT (pipeline,
459 "NOT adjusting base_time because start_time is NONE");
460 }
461 } else {
462 GST_DEBUG_OBJECT (pipeline,
463 "NOT adjusting base_time because we selected one before");
464 }
466 if (cur_clock)
467 gst_object_unref (cur_clock);
468 break;
469 }
470 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
471 {
472 /* we take a start_time snapshot before calling the children state changes
473 * so that they know about when the pipeline PAUSED. */
474 pipeline_update_start_time (element);
475 break;
476 }
477 case GST_STATE_CHANGE_PAUSED_TO_READY:
478 case GST_STATE_CHANGE_READY_TO_NULL:
479 break;
480 }
482 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
484 switch (transition) {
485 case GST_STATE_CHANGE_NULL_TO_READY:
486 break;
487 case GST_STATE_CHANGE_READY_TO_PAUSED:
488 {
489 reset_start_time (pipeline);
490 break;
491 }
492 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
493 break;
494 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
495 {
496 /* Take a new snapshot of the start_time after calling the state change on
497 * all children. This will be the running_time of the pipeline when we go
498 * back to PLAYING */
499 pipeline_update_start_time (element);
500 break;
501 }
502 case GST_STATE_CHANGE_PAUSED_TO_READY:
503 break;
504 case GST_STATE_CHANGE_READY_TO_NULL:
505 {
506 GstBus *bus;
507 gboolean auto_flush;
509 /* grab some stuff before we release the lock to flush out the bus */
510 GST_OBJECT_LOCK (element);
511 if ((bus = element->bus))
512 gst_object_ref (bus);
513 auto_flush = pipeline->priv->auto_flush_bus;
514 GST_OBJECT_UNLOCK (element);
516 if (bus) {
517 if (auto_flush) {
518 gst_bus_set_flushing (bus, TRUE);
519 } else {
520 GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
521 }
522 gst_object_unref (bus);
523 }
524 break;
525 }
526 }
527 return result;
529 /* ERRORS */
530 invalid_clock:
531 {
532 /* we generate this error when the selected clock was not
533 * accepted by some element */
534 GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
535 (_("Selected clock cannot be used in pipeline.")),
536 ("Pipeline cannot operate with selected clock"));
537 GST_DEBUG_OBJECT (pipeline,
538 "Pipeline cannot operate with selected clock %p", clock);
539 if (clock)
540 gst_object_unref (clock);
541 return GST_STATE_CHANGE_FAILURE;
542 }
543 }
545 /* intercept the bus messages from our children. We watch for the ASYNC_START
546 * message with is posted by the elements (sinks) that require a reset of the
547 * running_time after a flush. ASYNC_START also brings the pipeline back into
548 * the PAUSED, pending PAUSED state. When the ASYNC_DONE message is received the
549 * pipeline will redistribute the new base_time and will bring the elements back
550 * to the desired state of the pipeline. */
551 static void
552 gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
553 {
554 GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
556 switch (GST_MESSAGE_TYPE (message)) {
557 case GST_MESSAGE_ASYNC_START:
558 {
559 gboolean new_base_time;
561 gst_message_parse_async_start (message, &new_base_time);
563 /* reset our running time if we need to distribute a new base_time to the
564 * children. */
565 if (new_base_time)
566 reset_start_time (pipeline);
568 break;
569 }
570 case GST_MESSAGE_CLOCK_LOST:
571 {
572 GstClock *clock;
574 gst_message_parse_clock_lost (message, &clock);
576 GST_OBJECT_LOCK (bin);
577 if (clock == GST_ELEMENT_CAST (bin)->clock) {
578 GST_DEBUG_OBJECT (bin, "Used clock '%s' got lost",
579 GST_OBJECT_NAME (clock));
580 pipeline->priv->update_clock = TRUE;
581 }
582 GST_OBJECT_UNLOCK (bin);
583 }
584 default:
585 break;
586 }
587 GST_BIN_CLASS (parent_class)->handle_message (bin, message);
588 }
590 /**
591 * gst_pipeline_get_bus:
592 * @pipeline: a #GstPipeline
593 *
594 * Gets the #GstBus of @pipeline. The bus allows applications to receive
595 * #GstMessage packets.
596 *
597 * Returns: (transfer full): a #GstBus, unref after usage.
598 *
599 * MT safe.
600 */
601 GstBus *
602 gst_pipeline_get_bus (GstPipeline * pipeline)
603 {
604 return gst_element_get_bus (GST_ELEMENT_CAST (pipeline));
605 }
607 /**
608 * gst_pipeline_set_new_stream_time:
609 * @pipeline: a #GstPipeline
610 * @time: the new running time to set
611 *
612 * Set the new start time of @pipeline to @time. The start time is used to
613 * set the base time on the elements (see gst_element_set_base_time())
614 * in the PAUSED->PLAYING state transition.
615 *
616 * Setting @time to #GST_CLOCK_TIME_NONE will disable the pipeline's management
617 * of element base time. The application will then be responsible for
618 * performing base time distribution. This is sometimes useful if you want to
619 * synchronize capture from multiple pipelines, and you can also ensure that the
620 * pipelines have the same clock.
621 *
622 * MT safe.
623 *
624 * Deprecated: This function has the wrong name and is equivalent to
625 * gst_element_set_start_time().
626 */
627 #ifndef GST_REMOVE_DEPRECATED
628 #ifdef GST_DISABLE_DEPRECATED
629 void
630 gst_pipeline_set_new_stream_time (GstPipeline * pipeline, GstClockTime time);
631 #endif
632 void
633 gst_pipeline_set_new_stream_time (GstPipeline * pipeline, GstClockTime time)
634 {
635 g_return_if_fail (GST_IS_PIPELINE (pipeline));
637 gst_element_set_start_time (GST_ELEMENT_CAST (pipeline), time);
639 if (time == GST_CLOCK_TIME_NONE)
640 GST_DEBUG_OBJECT (pipeline, "told not to adjust base_time");
641 }
642 #endif /* GST_REMOVE_DEPRECATED */
644 /**
645 * gst_pipeline_get_last_stream_time:
646 * @pipeline: a #GstPipeline
647 *
648 * Gets the last running time of @pipeline. If the pipeline is PLAYING,
649 * the returned time is the running time used to configure the element's
650 * base time in the PAUSED->PLAYING state. If the pipeline is PAUSED, the
651 * returned time is the running time when the pipeline was paused.
652 *
653 * This function returns #GST_CLOCK_TIME_NONE if the pipeline was
654 * configured to not handle the management of the element's base time
655 * (see gst_pipeline_set_new_stream_time()).
656 *
657 * MT safe.
658 *
659 * Returns: a #GstClockTime.
660 *
661 * Deprecated: This function has the wrong name and is equivalent to
662 * gst_element_get_start_time().
663 */
664 #ifndef GST_REMOVE_DEPRECATED
665 #ifdef GST_DISABLE_DEPRECATED
666 GstClockTime gst_pipeline_get_last_stream_time (GstPipeline * pipeline);
667 #endif
668 GstClockTime
669 gst_pipeline_get_last_stream_time (GstPipeline * pipeline)
670 {
671 GstClockTime result;
673 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
675 result = gst_element_get_start_time (GST_ELEMENT_CAST (pipeline));
677 return result;
678 }
679 #endif /* GST_REMOVE_DEPRECATED */
681 static GstClock *
682 gst_pipeline_provide_clock_func (GstElement * element)
683 {
684 GstClock *clock = NULL;
685 GstPipeline *pipeline = GST_PIPELINE (element);
687 /* if we have a fixed clock, use that one */
688 GST_OBJECT_LOCK (pipeline);
689 if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
690 clock = pipeline->fixed_clock;
691 if (clock)
692 gst_object_ref (clock);
693 GST_OBJECT_UNLOCK (pipeline);
695 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
696 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
697 } else {
698 GST_OBJECT_UNLOCK (pipeline);
699 /* let the parent bin select a clock */
700 clock =
701 GST_ELEMENT_CLASS (parent_class)->provide_clock (GST_ELEMENT
702 (pipeline));
703 /* no clock, use a system clock */
704 if (!clock) {
705 clock = gst_system_clock_obtain ();
707 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
708 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
709 } else {
710 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
711 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
712 }
713 }
714 return clock;
715 }
717 /**
718 * gst_pipeline_get_clock:
719 * @pipeline: a #GstPipeline
720 *
721 * Gets the current clock used by @pipeline.
722 *
723 * Returns: (transfer full): a #GstClock, unref after usage.
724 */
725 GstClock *
726 gst_pipeline_get_clock (GstPipeline * pipeline)
727 {
728 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
730 return gst_pipeline_provide_clock_func (GST_ELEMENT_CAST (pipeline));
731 }
734 /**
735 * gst_pipeline_use_clock:
736 * @pipeline: a #GstPipeline
737 * @clock: (transfer none): the clock to use
738 *
739 * Force @pipeline to use the given @clock. The pipeline will
740 * always use the given clock even if new clock providers are added
741 * to this pipeline.
742 *
743 * If @clock is NULL all clocking will be disabled which will make
744 * the pipeline run as fast as possible.
745 *
746 * MT safe.
747 */
748 void
749 gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
750 {
751 GstClock **clock_p;
753 g_return_if_fail (GST_IS_PIPELINE (pipeline));
755 GST_OBJECT_LOCK (pipeline);
756 GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
758 clock_p = &pipeline->fixed_clock;
759 gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
760 GST_OBJECT_UNLOCK (pipeline);
762 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
763 (clock ? GST_OBJECT_NAME (clock) : "nil"));
764 }
766 /**
767 * gst_pipeline_set_clock:
768 * @pipeline: a #GstPipeline
769 * @clock: (transfer none): the clock to set
770 *
771 * Set the clock for @pipeline. The clock will be distributed
772 * to all the elements managed by the pipeline.
773 *
774 * Returns: TRUE if the clock could be set on the pipeline. FALSE if
775 * some element did not accept the clock.
776 *
777 * MT safe.
778 */
779 gboolean
780 gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
781 {
782 g_return_val_if_fail (pipeline != NULL, FALSE);
783 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
785 return
786 GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT_CAST (pipeline),
787 clock);
788 }
790 /**
791 * gst_pipeline_auto_clock:
792 * @pipeline: a #GstPipeline
793 *
794 * Let @pipeline select a clock automatically. This is the default
795 * behaviour.
796 *
797 * Use this function if you previous forced a fixed clock with
798 * gst_pipeline_use_clock() and want to restore the default
799 * pipeline clock selection algorithm.
800 *
801 * MT safe.
802 */
803 void
804 gst_pipeline_auto_clock (GstPipeline * pipeline)
805 {
806 GstClock **clock_p;
808 g_return_if_fail (pipeline != NULL);
809 g_return_if_fail (GST_IS_PIPELINE (pipeline));
811 GST_OBJECT_LOCK (pipeline);
812 GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
814 clock_p = &pipeline->fixed_clock;
815 gst_object_replace ((GstObject **) clock_p, NULL);
816 GST_OBJECT_UNLOCK (pipeline);
818 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
819 }
821 /**
822 * gst_pipeline_set_delay:
823 * @pipeline: a #GstPipeline
824 * @delay: the delay
825 *
826 * Set the expected delay needed for all elements to perform the
827 * PAUSED to PLAYING state change. @delay will be added to the
828 * base time of the elements so that they wait an additional @delay
829 * amount of time before starting to process buffers and cannot be
830 * #GST_CLOCK_TIME_NONE.
831 *
832 * This option is used for tuning purposes and should normally not be
833 * used.
834 *
835 * MT safe.
836 *
837 * Since: 0.10.5
838 */
839 void
840 gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
841 {
842 g_return_if_fail (GST_IS_PIPELINE (pipeline));
843 g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
845 GST_OBJECT_LOCK (pipeline);
846 pipeline->delay = delay;
847 GST_OBJECT_UNLOCK (pipeline);
848 }
850 /**
851 * gst_pipeline_get_delay:
852 * @pipeline: a #GstPipeline
853 *
854 * Get the configured delay (see gst_pipeline_set_delay()).
855 *
856 * Returns: The configured delay.
857 *
858 * MT safe.
859 *
860 * Since: 0.10.5
861 */
862 GstClockTime
863 gst_pipeline_get_delay (GstPipeline * pipeline)
864 {
865 GstClockTime res;
867 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
869 GST_OBJECT_LOCK (pipeline);
870 res = pipeline->delay;
871 GST_OBJECT_UNLOCK (pipeline);
873 return res;
874 }
876 /**
877 * gst_pipeline_set_auto_flush_bus:
878 * @pipeline: a #GstPipeline
879 * @auto_flush: whether or not to automatically flush the bus when
880 * the pipeline goes from READY to NULL state
881 *
882 * Usually, when a pipeline goes from READY to NULL state, it automatically
883 * flushes all pending messages on the bus, which is done for refcounting
884 * purposes, to break circular references.
885 *
886 * This means that applications that update state using (async) bus messages
887 * (e.g. do certain things when a pipeline goes from PAUSED to READY) might
888 * not get to see messages when the pipeline is shut down, because they might
889 * be flushed before they can be dispatched in the main thread. This behaviour
890 * can be disabled using this function.
891 *
892 * It is important that all messages on the bus are handled when the
893 * automatic flushing is disabled else memory leaks will be introduced.
894 *
895 * MT safe.
896 *
897 * Since: 0.10.4
898 */
899 void
900 gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
901 {
902 g_return_if_fail (GST_IS_PIPELINE (pipeline));
904 GST_OBJECT_LOCK (pipeline);
905 pipeline->priv->auto_flush_bus = auto_flush;
906 GST_OBJECT_UNLOCK (pipeline);
907 }
909 /**
910 * gst_pipeline_get_auto_flush_bus:
911 * @pipeline: a #GstPipeline
912 *
913 * Check if @pipeline will automatically flush messages when going to
914 * the NULL state.
915 *
916 * Returns: whether the pipeline will automatically flush its bus when
917 * going from READY to NULL state or not.
918 *
919 * MT safe.
920 *
921 * Since: 0.10.4
922 */
923 gboolean
924 gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
925 {
926 gboolean res;
928 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
930 GST_OBJECT_LOCK (pipeline);
931 res = pipeline->priv->auto_flush_bus;
932 GST_OBJECT_UNLOCK (pipeline);
934 return res;
935 }