3 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
4 * 2004 Wim Taymans <wim.taymans@gmail.com>
6 * gstbin.c: GstBin container object and support code
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
27 * @short_description: Base class and element that can contain other elements
29 * #GstBin is an element that can contain other #GstElement, allowing them to be
31 * Pads from the child elements can be ghosted to the bin, see #GstGhostPad.
32 * This makes the bin look like any other elements and enables creation of
33 * higher-level abstraction elements.
35 * A new #GstBin is created with gst_bin_new(). Use a #GstPipeline instead if you
36 * want to create a toplevel bin because a normal bin doesn't have a bus or
37 * handle clock distribution of its own.
39 * After the bin has been created you will typically add elements to it with
40 * gst_bin_add(). You can remove elements with gst_bin_remove().
42 * An element can be retrieved from a bin with gst_bin_get_by_name(), using the
43 * elements name. gst_bin_get_by_name_recurse_up() is mainly used for internal
44 * purposes and will query the parent bins when the element is not found in the
47 * An iterator of elements in a bin can be retrieved with
48 * gst_bin_iterate_elements(). Various other iterators exist to retrieve the
51 * gst_object_unref() is used to drop your reference to the bin.
53 * The #GstBin::element-added signal is fired whenever a new element is added to
54 * the bin. Likewise the #GstBin::element-removed signal is fired whenever an
55 * element is removed from the bin.
57 * A #GstBin internally intercepts every #GstMessage posted by its children and
58 * implements the following default behaviour for each of them:
60 * * %GST_MESSAGE_EOS: This message is only posted by sinks in the PLAYING
61 * state. If all sinks posted the EOS message, this bin will post and EOS
64 * * %GST_MESSAGE_SEGMENT_START: Just collected and never forwarded upwards.
65 * The messages are used to decide when all elements have completed playback
68 * * %GST_MESSAGE_SEGMENT_DONE: Is posted by #GstBin when all elements that posted
69 * a SEGMENT_START have posted a SEGMENT_DONE.
71 * * %GST_MESSAGE_DURATION_CHANGED: Is posted by an element that detected a change
72 * in the stream duration. The duration change is posted to the
73 * application so that it can refetch the new duration with a duration
76 * Note that these messages can be posted before the bin is prerolled, in which
77 * case the duration query might fail.
79 * Note also that there might be a discrepancy (due to internal buffering/queueing)
80 * between the stream being currently displayed and the returned duration query.
82 * Applications might want to also query for duration (and changes) by
83 * listening to the %GST_MESSAGE_STREAM_START message, signaling the active start
86 * * %GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
87 * can no longer provide a clock.
89 * The default bin behaviour is to check if the lost clock was the one provided
90 * by the bin. If so and the bin is currently in the PLAYING state, the message
91 * is forwarded to the bin parent.
93 * This message is also generated when a clock provider is removed from
94 * the bin. If this message is received by the application, it should
95 * PAUSE the pipeline and set it back to PLAYING to force a new clock
98 * * %GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
99 * can provide a clock. This mostly happens when a new clock
100 * provider is added to the bin.
102 * The default behaviour of the bin is to mark the currently selected clock as
103 * dirty, which will perform a clock recalculation the next time the bin is
104 * asked to provide a clock.
106 * This message is never sent to the application but is forwarded to
107 * the parent of the bin.
109 * * OTHERS: posted upwards.
111 * A #GstBin implements the following default behaviour for answering to a
114 * * %GST_QUERY_DURATION: The bin will forward the query to all sink
115 * elements contained within and will return the maximum value.
116 * If no sinks are available in the bin, the query fails.
118 * * %GST_QUERY_POSITION: The query is sent to all sink elements in the bin and the
119 * MAXIMUM of all values is returned. If no sinks are available in the bin,
122 * * OTHERS: the query is forwarded to all sink elements, the result
123 * of the first sink that answers the query successfully is returned. If no
124 * sink is in the bin, the query fails.
126 * A #GstBin will by default forward any event sent to it to all sink
127 * ( %GST_EVENT_TYPE_DOWNSTREAM ) or source ( %GST_EVENT_TYPE_UPSTREAM ) elements
128 * depending on the event type.
130 * If all the elements return %TRUE, the bin will also return %TRUE, else %FALSE
131 * is returned. If no elements of the required type are in the bin, the event
132 * handler will return %TRUE.
135 #include "gst_private.h"
137 #include "gstevent.h"
140 #include "gsterror.h"
142 #include "gstutils.h"
143 #include "gstchildproxy.h"
145 GST_DEBUG_CATEGORY_STATIC (bin_debug);
146 #define GST_CAT_DEFAULT bin_debug
148 /* a bin is toplevel if it has no parent or when it is configured to behave like
150 #define BIN_IS_TOPLEVEL(bin) ((GST_OBJECT_PARENT (bin) == NULL) || bin->priv->asynchandling)
152 struct _GstBinPrivate
154 gboolean asynchandling;
155 /* if we get an ASYNC_DONE message from ourselves, this means that the
156 * subclass will simulate ASYNC behaviour without having ASYNC children. When
157 * such an ASYNC_DONE message is posted while we are doing a state change, we
158 * have to process the message after finishing the state change even when no
159 * child returned GST_STATE_CHANGE_ASYNC. */
160 gboolean pending_async_done;
162 guint32 structure_cookie;
169 /* forward messages from our children */
170 gboolean message_forward;
173 gboolean posted_playing;
174 GstElementFlags suppressed_flags;
183 static void gst_bin_dispose (GObject * object);
185 static void gst_bin_set_property (GObject * object, guint prop_id,
186 const GValue * value, GParamSpec * pspec);
187 static void gst_bin_get_property (GObject * object, guint prop_id,
188 GValue * value, GParamSpec * pspec);
190 static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
191 GstStateChange transition);
192 static gboolean gst_bin_post_message (GstElement * element, GstMessage * msg);
193 static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
194 GstState * state, GstState * pending, GstClockTime timeout);
195 static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
196 gboolean flag_pending, GstClockTime running_time);
197 static void bin_handle_async_start (GstBin * bin);
198 static void bin_push_state_continue (GstBin * bin, BinContinueData * data);
199 static void bin_do_eos (GstBin * bin);
201 static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
202 static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
203 static void gst_bin_deep_element_added_func (GstBin * bin, GstBin * sub_bin,
204 GstElement * element);
205 static void gst_bin_deep_element_removed_func (GstBin * bin, GstBin * sub_bin,
206 GstElement * element);
207 static void gst_bin_update_context (GstBin * bin, GstContext * context);
208 static void gst_bin_update_context_unlocked (GstBin * bin,
209 GstContext * context);
212 static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
213 static GstIndex *gst_bin_get_index_func (GstElement * element);
216 static GstClock *gst_bin_provide_clock_func (GstElement * element);
217 static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
219 static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
220 static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
221 static GstBusSyncReply bin_bus_handler (GstBus * bus,
222 GstMessage * message, GstBin * bin);
223 static gboolean gst_bin_query (GstElement * element, GstQuery * query);
224 static void gst_bin_set_context (GstElement * element, GstContext * context);
226 static gboolean gst_bin_do_latency_func (GstBin * bin);
228 static void bin_remove_messages (GstBin * bin, GstObject * src,
229 GstMessageType types);
230 static void gst_bin_continue_func (GstBin * bin, BinContinueData * data);
231 static gint bin_element_is_sink (GstElement * child, GstBin * bin);
232 static gint bin_element_is_src (GstElement * child, GstBin * bin);
234 static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
236 /* Bin signals and properties */
243 DEEP_ELEMENT_REMOVED,
247 #define DEFAULT_ASYNC_HANDLING FALSE
248 #define DEFAULT_MESSAGE_FORWARD FALSE
254 PROP_MESSAGE_FORWARD,
258 static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
260 static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
264 static const GInterfaceInfo iface_info = { \
265 gst_bin_child_proxy_init, \
269 g_type_add_interface_static (g_define_type_id, GST_TYPE_CHILD_PROXY, &iface_info); \
271 GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
272 "debugging info for the 'bin' container element"); \
276 #define gst_bin_parent_class parent_class
277 G_DEFINE_TYPE_WITH_CODE (GstBin, gst_bin, GST_TYPE_ELEMENT,
278 G_ADD_PRIVATE (GstBin)
282 gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
288 bin = GST_BIN_CAST (child_proxy);
290 GST_OBJECT_LOCK (bin);
291 if ((res = g_list_nth_data (bin->children, index)))
292 gst_object_ref (res);
293 GST_OBJECT_UNLOCK (bin);
295 return (GObject *) res;
299 gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
304 bin = GST_BIN_CAST (child_proxy);
306 GST_OBJECT_LOCK (bin);
307 num = bin->numchildren;
308 GST_OBJECT_UNLOCK (bin);
314 gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
316 GstChildProxyInterface *iface = g_iface;
318 iface->get_children_count = gst_bin_child_proxy_get_children_count;
319 iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
323 _gst_boolean_accumulator (GSignalInvocationHint * ihint,
324 GValue * return_accu, const GValue * handler_return, gpointer dummy)
328 myboolean = g_value_get_boolean (handler_return);
329 g_value_set_boolean (return_accu, myboolean);
331 GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
338 gst_bin_class_init (GstBinClass * klass)
340 GObjectClass *gobject_class;
341 GstElementClass *gstelement_class;
343 gobject_class = (GObjectClass *) klass;
344 gstelement_class = (GstElementClass *) klass;
346 gobject_class->set_property = gst_bin_set_property;
347 gobject_class->get_property = gst_bin_get_property;
350 * GstBin:async-handling:
352 * If set to %TRUE, the bin will handle asynchronous state changes.
353 * This should be used only if the bin subclass is modifying the state
354 * of its children on its own.
356 g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
357 g_param_spec_boolean ("async-handling", "Async Handling",
358 "The bin will handle Asynchronous state changes",
359 DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
362 * GstBin::element-added:
364 * @element: the #GstElement that was added to the bin
366 * Will be emitted after the element was added to the bin.
368 gst_bin_signals[ELEMENT_ADDED] =
369 g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
370 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
371 NULL, NULL, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
373 * GstBin::element-removed:
375 * @element: the #GstElement that was removed from the bin
377 * Will be emitted after the element was removed from the bin.
379 gst_bin_signals[ELEMENT_REMOVED] =
380 g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
381 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
382 NULL, NULL, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
384 * GstBin::deep-element-added:
386 * @sub_bin: the #GstBin the element was added to
387 * @element: the #GstElement that was added to @sub_bin
389 * Will be emitted after the element was added to @sub_bin.
393 gst_bin_signals[DEEP_ELEMENT_ADDED] =
394 g_signal_new ("deep-element-added", G_TYPE_FROM_CLASS (klass),
395 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, deep_element_added),
396 NULL, NULL, NULL, G_TYPE_NONE, 2, GST_TYPE_BIN, GST_TYPE_ELEMENT);
398 * GstBin::deep-element-removed:
400 * @sub_bin: the #GstBin the element was removed from
401 * @element: the #GstElement that was removed from @sub_bin
403 * Will be emitted after the element was removed from @sub_bin.
407 gst_bin_signals[DEEP_ELEMENT_REMOVED] =
408 g_signal_new ("deep-element-removed", G_TYPE_FROM_CLASS (klass),
409 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, deep_element_removed),
410 NULL, NULL, NULL, G_TYPE_NONE, 2, GST_TYPE_BIN, GST_TYPE_ELEMENT);
412 * GstBin::do-latency:
415 * Will be emitted when the bin needs to perform latency calculations. This
416 * signal is only emitted for toplevel bins or when #GstBin:async-handling is
419 * Only one signal handler is invoked. If no signals are connected, the
420 * default handler is invoked, which will query and distribute the lowest
421 * possible latency to all sinks.
423 * Connect to this signal if the default latency calculations are not
424 * sufficient, like when you need different latencies for different sinks in
427 gst_bin_signals[DO_LATENCY] =
428 g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
429 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
430 _gst_boolean_accumulator, NULL, NULL, G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
433 * GstBin:message-forward:
435 * Forward all children messages, even those that would normally be filtered by
436 * the bin. This can be interesting when one wants to be notified of the EOS
437 * state of individual elements, for example.
439 * The messages are converted to an ELEMENT message with the bin as the
440 * source. The structure of the message is named `GstBinForwarded` and contains
441 * a field named `message` of type %GST_TYPE_MESSAGE that contains the original
444 g_object_class_install_property (gobject_class, PROP_MESSAGE_FORWARD,
445 g_param_spec_boolean ("message-forward", "Message Forward",
446 "Forwards all children messages",
447 DEFAULT_MESSAGE_FORWARD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
449 gobject_class->dispose = gst_bin_dispose;
451 gst_element_class_set_static_metadata (gstelement_class, "Generic bin",
453 "Simple container object",
454 "Erik Walthinsen <omega@cse.ogi.edu>,"
455 "Wim Taymans <wim.taymans@gmail.com>");
457 gstelement_class->change_state =
458 GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
459 gstelement_class->post_message = GST_DEBUG_FUNCPTR (gst_bin_post_message);
460 gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
462 gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
463 gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
465 gstelement_class->provide_clock =
466 GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
467 gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
469 gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
470 gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
471 gstelement_class->set_context = GST_DEBUG_FUNCPTR (gst_bin_set_context);
473 klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
474 klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
475 klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
477 klass->deep_element_added = gst_bin_deep_element_added_func;
478 klass->deep_element_removed = gst_bin_deep_element_removed_func;
480 klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
484 gst_bin_init (GstBin * bin)
488 bin->numchildren = 0;
489 bin->children = NULL;
490 bin->children_cookie = 0;
491 bin->messages = NULL;
492 bin->provided_clock = NULL;
493 bin->clock_dirty = FALSE;
495 /* Set up a bus for listening to child elements */
496 bus = g_object_new (GST_TYPE_BUS, "enable-async", FALSE, NULL);
497 gst_object_ref_sink (bus);
498 bin->child_bus = bus;
499 GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
501 gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin,
504 bin->priv = gst_bin_get_instance_private (bin);
505 bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
506 bin->priv->structure_cookie = 0;
507 bin->priv->message_forward = DEFAULT_MESSAGE_FORWARD;
511 gst_bin_dispose (GObject * object)
513 GstBin *bin = GST_BIN_CAST (object);
514 GstBus **child_bus_p = &bin->child_bus;
515 GstClock **provided_clock_p = &bin->provided_clock;
516 GstElement **clock_provider_p = &bin->clock_provider;
518 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "%p dispose", object);
520 GST_OBJECT_LOCK (object);
521 gst_object_replace ((GstObject **) child_bus_p, NULL);
522 gst_object_replace ((GstObject **) provided_clock_p, NULL);
523 gst_object_replace ((GstObject **) clock_provider_p, NULL);
524 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
525 GST_OBJECT_UNLOCK (object);
527 while (bin->children) {
528 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
530 if (G_UNLIKELY (bin->children != NULL)) {
531 g_critical ("could not remove elements from bin '%s'",
532 GST_STR_NULL (GST_OBJECT_NAME (object)));
535 G_OBJECT_CLASS (parent_class)->dispose (object);
540 * @name: (allow-none): the name of the new bin
542 * Creates a new bin with the given name.
544 * Returns: (transfer floating): a new #GstBin
547 gst_bin_new (const gchar * name)
549 return gst_element_factory_make ("bin", name);
553 gst_bin_set_property (GObject * object, guint prop_id,
554 const GValue * value, GParamSpec * pspec)
558 gstbin = GST_BIN_CAST (object);
561 case PROP_ASYNC_HANDLING:
562 GST_OBJECT_LOCK (gstbin);
563 gstbin->priv->asynchandling = g_value_get_boolean (value);
564 GST_OBJECT_UNLOCK (gstbin);
566 case PROP_MESSAGE_FORWARD:
567 GST_OBJECT_LOCK (gstbin);
568 gstbin->priv->message_forward = g_value_get_boolean (value);
569 GST_OBJECT_UNLOCK (gstbin);
572 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
578 gst_bin_get_property (GObject * object, guint prop_id,
579 GValue * value, GParamSpec * pspec)
583 gstbin = GST_BIN_CAST (object);
586 case PROP_ASYNC_HANDLING:
587 GST_OBJECT_LOCK (gstbin);
588 g_value_set_boolean (value, gstbin->priv->asynchandling);
589 GST_OBJECT_UNLOCK (gstbin);
591 case PROP_MESSAGE_FORWARD:
592 GST_OBJECT_LOCK (gstbin);
593 g_value_set_boolean (value, gstbin->priv->message_forward);
594 GST_OBJECT_UNLOCK (gstbin);
597 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
603 /* return the cached index */
605 gst_bin_get_index_func (GstElement * element)
610 bin = GST_BIN_CAST (element);
612 GST_OBJECT_LOCK (bin);
613 if ((result = bin->priv->index))
614 gst_object_ref (result);
615 GST_OBJECT_UNLOCK (bin);
620 /* set the index on all elements in this bin
625 gst_bin_set_index_func (GstElement * element, GstIndex * index)
631 GValue data = { 0, };
633 bin = GST_BIN_CAST (element);
635 GST_OBJECT_LOCK (bin);
636 old = bin->priv->index;
637 if (G_UNLIKELY (old == index))
640 gst_object_ref (index);
641 bin->priv->index = index;
642 GST_OBJECT_UNLOCK (bin);
645 gst_object_unref (old);
647 it = gst_bin_iterate_elements (bin);
649 /* set the index on all elements in the bin */
652 switch (gst_iterator_next (it, &data)) {
653 case GST_ITERATOR_OK:
655 GstElement *child = g_value_get_object (&data);
657 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
658 GST_ELEMENT_NAME (child));
659 gst_element_set_index (child, index);
661 g_value_reset (&data);
664 case GST_ITERATOR_RESYNC:
665 GST_DEBUG_OBJECT (bin, "iterator doing resync");
666 gst_iterator_resync (it);
669 case GST_ITERATOR_DONE:
670 GST_DEBUG_OBJECT (bin, "iterator done");
675 g_value_unset (&data);
676 gst_iterator_free (it);
681 GST_DEBUG_OBJECT (bin, "index was already set");
682 GST_OBJECT_UNLOCK (bin);
688 /* set the clock on all elements in this bin
693 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
699 GValue data = { 0, };
701 bin = GST_BIN_CAST (element);
703 it = gst_bin_iterate_elements (bin);
707 switch (gst_iterator_next (it, &data)) {
708 case GST_ITERATOR_OK:
710 GstElement *child = g_value_get_object (&data);
712 res &= gst_element_set_clock (child, clock);
714 g_value_reset (&data);
717 case GST_ITERATOR_RESYNC:
718 GST_DEBUG_OBJECT (bin, "iterator doing resync");
719 gst_iterator_resync (it);
723 case GST_ITERATOR_DONE:
724 GST_DEBUG_OBJECT (bin, "iterator done");
729 g_value_unset (&data);
730 gst_iterator_free (it);
733 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
738 /* get the clock for this bin by asking all of the children in this bin
740 * The ref of the returned clock in increased so unref after usage.
742 * We loop the elements in state order and pick the last clock we can
743 * get. This makes sure we get a clock from the source.
748 gst_bin_provide_clock_func (GstElement * element)
750 GstClock *result = NULL;
751 GstElement *provider = NULL;
756 GstClock **provided_clock_p;
757 GstElement **clock_provider_p;
759 bin = GST_BIN_CAST (element);
761 GST_OBJECT_LOCK (bin);
762 if (!bin->clock_dirty)
765 GST_DEBUG_OBJECT (bin, "finding new clock");
767 it = gst_bin_sort_iterator_new (bin);
768 GST_OBJECT_UNLOCK (bin);
772 switch (gst_iterator_next (it, &val)) {
773 case GST_ITERATOR_OK:
775 GstElement *child = g_value_get_object (&val);
778 clock = gst_element_provide_clock (child);
780 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
781 clock, GST_ELEMENT_NAME (child));
783 gst_object_unref (result);
784 gst_object_unref (provider);
787 provider = gst_object_ref (child);
790 g_value_reset (&val);
793 case GST_ITERATOR_RESYNC:
794 gst_iterator_resync (it);
797 case GST_ITERATOR_DONE:
802 g_value_unset (&val);
803 gst_iterator_free (it);
805 GST_OBJECT_LOCK (bin);
806 if (!bin->clock_dirty) {
808 gst_object_unref (provider);
810 gst_object_unref (result);
816 provided_clock_p = &bin->provided_clock;
817 clock_provider_p = &bin->clock_provider;
818 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
819 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
820 bin->clock_dirty = FALSE;
821 GST_DEBUG_OBJECT (bin,
822 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
824 /* Provider is not being returned to caller, just the result */
826 gst_object_unref (provider);
827 GST_OBJECT_UNLOCK (bin);
833 if ((result = bin->provided_clock))
834 gst_object_ref (result);
835 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
836 GST_OBJECT_UNLOCK (bin);
843 * functions for manipulating cached messages
848 GstMessageType types;
851 /* check if a message is of given src and type */
853 message_check (GstMessage * message, MessageFind * target)
858 eq &= GST_MESSAGE_SRC (message) == target->src;
860 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
861 GST_LOG ("looking at message %p: %d", message, eq);
867 find_message (GstBin * bin, GstObject * src, GstMessageType types)
875 result = g_list_find_custom (bin->messages, &find,
876 (GCompareFunc) message_check);
879 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
880 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
883 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
884 #ifndef GST_DISABLE_GST_DEBUG
888 for (i = 0; i < 32; i++)
889 if (types & (1U << i))
890 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1U << i));
898 /* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
901 * A message that is cached and has the same SRC and type is replaced
902 * by the given message.
905 bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
911 if ((src = GST_MESSAGE_SRC (message))) {
912 /* first find the previous message posted by this element */
913 if ((previous = find_message (bin, src, types))) {
914 GstMessage *previous_msg;
916 /* if we found a previous message, replace it */
917 previous_msg = previous->data;
918 previous->data = message;
920 GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
921 GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
922 GST_MESSAGE_TYPE_NAME (message));
924 gst_message_unref (previous_msg);
926 /* keep new message */
927 bin->messages = g_list_prepend (bin->messages, message);
929 GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
930 message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
933 GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
934 GST_MESSAGE_TYPE_NAME (message));
936 gst_message_unref (message);
941 /* with LOCK. Remove all messages of given types */
943 bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
951 for (walk = bin->messages; walk; walk = next) {
952 GstMessage *message = (GstMessage *) walk->data;
954 next = g_list_next (walk);
956 if (message_check (message, &find) == 0) {
957 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
958 "deleting message %p of type %s (types 0x%08x)", message,
959 GST_MESSAGE_TYPE_NAME (message), types);
960 bin->messages = g_list_delete_link (bin->messages, walk);
961 gst_message_unref (message);
963 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
964 "not deleting message %p of type 0x%08x", message,
965 GST_MESSAGE_TYPE (message));
971 /* Check if the bin is EOS. We do this by scanning all sinks and
972 * checking if they posted an EOS message.
974 * call with bin LOCK */
976 is_eos (GstBin * bin, guint32 * seqnum)
983 for (walk = bin->children; walk; walk = g_list_next (walk)) {
986 element = GST_ELEMENT_CAST (walk->data);
987 if (bin_element_is_sink (element, bin) == 0) {
988 /* check if element posted EOS */
990 find_message (bin, GST_OBJECT_CAST (element), GST_MESSAGE_EOS))) {
991 GST_DEBUG ("sink '%s' posted EOS", GST_ELEMENT_NAME (element));
992 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
995 GST_DEBUG ("sink '%s' did not post EOS yet",
996 GST_ELEMENT_NAME (element));
1002 /* FIXME: Some tests (e.g. elements/capsfilter) use
1003 * pipelines with a dangling sinkpad but no sink element.
1004 * These tests assume that no EOS message is ever
1005 * posted on the bus so let's keep that behaviour.
1006 * In valid pipelines this doesn't make a difference.
1008 return result && n_eos > 0;
1012 /* Check if the bin is STREAM_START. We do this by scanning all sinks and
1013 * checking if they posted an STREAM_START message.
1015 * call with bin LOCK */
1017 is_stream_start (GstBin * bin, guint32 * seqnum, gboolean * have_group_id,
1023 gboolean first_stream_start = TRUE, first_group_id = TRUE;
1024 gboolean same_group_id = TRUE;
1026 *have_group_id = FALSE;
1029 for (walk = bin->children; walk; walk = g_list_next (walk)) {
1030 GstElement *element;
1032 element = GST_ELEMENT_CAST (walk->data);
1033 if (bin_element_is_sink (element, bin) == 0) {
1034 /* check if element posted STREAM_START */
1036 find_message (bin, GST_OBJECT_CAST (element),
1037 GST_MESSAGE_STREAM_START))) {
1038 /* Only initialize to TRUE if we have any stream-start messages at
1039 * all, otherwise it should be FALSE. */
1040 if (first_stream_start) {
1041 /* If any stream-start message do not contain a group id then we
1042 * will set it to FALSE below */
1043 *have_group_id = TRUE;
1044 /* Similarly if any sinks did not post stream-start then we will
1045 * set it to FALSE afterwards */
1047 first_stream_start = FALSE;
1050 GST_DEBUG ("sink '%s' posted STREAM_START", GST_ELEMENT_NAME (element));
1051 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1052 if (gst_message_parse_group_id (GST_MESSAGE_CAST (msgs->data),
1054 if (first_group_id) {
1055 first_group_id = FALSE;
1056 *group_id = tmp_group_id;
1058 if (tmp_group_id != *group_id)
1059 same_group_id = FALSE;
1062 *have_group_id = FALSE;
1065 GST_DEBUG ("sink '%s' did not post STREAM_START yet",
1066 GST_ELEMENT_NAME (element));
1073 /* If all have a group_id we only consider this stream started
1074 * if all group ids were the same and all sinks posted a stream-start
1077 return same_group_id && result;
1078 /* otherwise consider this stream started after all sinks
1079 * have reported stream-start for backward compatibility.
1080 * FIXME 2.0: This should go away! */
1085 unlink_pads (const GValue * item, gpointer user_data)
1090 pad = g_value_get_object (item);
1092 if ((peer = gst_pad_get_peer (pad))) {
1093 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
1094 gst_pad_unlink (pad, peer);
1096 gst_pad_unlink (peer, pad);
1097 gst_object_unref (peer);
1102 bin_deep_iterator_foreach (const GValue * item, gpointer user_data)
1104 GQueue *queue = user_data;
1106 g_queue_push_tail (queue, g_value_dup_object (item));
1110 gst_bin_do_deep_add_remove (GstBin * bin, gint sig_id, const gchar * sig_name,
1111 GstElement * element)
1113 g_signal_emit (bin, sig_id, 0, bin, element);
1115 /* When removing a bin, emit deep-element-* for everything in the bin too */
1116 if (GST_IS_BIN (element)) {
1118 GstIteratorResult ires;
1119 GQueue elements = G_QUEUE_INIT;
1121 GST_LOG_OBJECT (bin, "Recursing into bin %" GST_PTR_FORMAT " for %s",
1123 it = gst_bin_iterate_recurse (GST_BIN_CAST (element));
1125 ires = gst_iterator_foreach (it, bin_deep_iterator_foreach, &elements);
1126 if (ires != GST_ITERATOR_DONE) {
1127 g_queue_foreach (&elements, (GFunc) gst_object_unref, NULL);
1128 g_queue_clear (&elements);
1130 if (ires == GST_ITERATOR_RESYNC)
1131 gst_iterator_resync (it);
1132 } while (ires == GST_ITERATOR_RESYNC);
1133 if (ires != GST_ITERATOR_ERROR) {
1136 while ((e = g_queue_pop_head (&elements))) {
1137 GstObject *parent = gst_object_get_parent (GST_OBJECT_CAST (e));
1139 /* an element could have removed some of its internal elements
1140 * meanwhile, so protect against that */
1142 GST_LOG_OBJECT (bin, "calling %s for element %" GST_PTR_FORMAT
1143 " in bin %" GST_PTR_FORMAT, sig_name, e, parent);
1144 g_signal_emit (bin, sig_id, 0, parent, e);
1145 gst_object_unref (parent);
1146 gst_object_unref (e);
1150 gst_iterator_free (it);
1154 /* vmethod that adds an element to a bin
1159 gst_bin_add_func (GstBin * bin, GstElement * element)
1163 gboolean is_sink, is_source, provides_clock, requires_clock;
1164 GstMessage *clock_message = NULL, *async_message = NULL;
1165 GstStateChangeReturn ret;
1166 GList *l, *elem_contexts, *need_context_messages;
1168 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1170 /* we obviously can't add ourself to ourself */
1171 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1174 /* get the element name to make sure it is unique in this bin. */
1175 GST_OBJECT_LOCK (element);
1176 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1177 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1178 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1180 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1182 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1183 GST_OBJECT_UNLOCK (element);
1185 GST_OBJECT_LOCK (bin);
1187 /* then check to see if the element's name is already taken in the bin,
1188 * we can safely take the lock here. This check is probably bogus because
1189 * you can safely change the element name after this check and before setting
1190 * the object parent. The window is very small though... */
1191 if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
1192 goto duplicate_name;
1194 /* set the element's parent and add the element to the bin's list of children */
1195 if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
1196 GST_OBJECT_CAST (bin))))
1199 /* if we add a sink we become a sink */
1200 if (is_sink && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SINK)) {
1201 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
1203 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SINK);
1205 if (is_source && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SOURCE)) {
1206 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was source",
1208 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SOURCE);
1211 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_PROVIDE_CLOCK)) {
1212 GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
1214 gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
1215 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1218 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_REQUIRE_CLOCK)) {
1219 GST_DEBUG_OBJECT (bin, "element \"%s\" requires a clock", elem_name);
1220 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1223 bin->children = g_list_prepend (bin->children, element);
1225 bin->children_cookie++;
1226 if (!GST_BIN_IS_NO_RESYNC (bin))
1227 bin->priv->structure_cookie++;
1229 /* distribute the bus */
1230 gst_element_set_bus (element, bin->child_bus);
1232 /* propagate the current base_time, start_time and clock */
1233 gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
1234 gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
1235 /* it's possible that the element did not accept the clock but
1236 * that is not important right now. When the pipeline goes to PLAYING,
1237 * a new clock will be selected */
1238 gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
1240 /* get the element's list of contexts before propagating our own */
1241 elem_contexts = gst_element_get_contexts (element);
1242 for (l = GST_ELEMENT_CAST (bin)->contexts; l; l = l->next)
1243 gst_element_set_context (element, l->data);
1245 need_context_messages = NULL;
1246 for (l = elem_contexts; l; l = l->next) {
1247 GstContext *replacement, *context = l->data;
1248 const gchar *context_type;
1250 context_type = gst_context_get_context_type (context);
1252 /* we already set this context above? */
1254 gst_element_get_context_unlocked (GST_ELEMENT (bin), context_type);
1256 gst_context_unref (replacement);
1261 /* ask our parent for the context */
1262 msg = gst_message_new_need_context (GST_OBJECT_CAST (bin), context_type);
1263 s = (GstStructure *) gst_message_get_structure (msg);
1264 gst_structure_set (s, "bin.old.context", GST_TYPE_CONTEXT, context, NULL);
1266 need_context_messages = g_list_prepend (need_context_messages, msg);
1271 /* set the cached index on the children */
1272 if (bin->priv->index)
1273 gst_element_set_index (element, bin->priv->index);
1276 ret = GST_STATE_RETURN (bin);
1277 /* no need to update the state if we are in error */
1278 if (ret == GST_STATE_CHANGE_FAILURE)
1279 goto no_state_recalc;
1281 /* update the bin state, the new element could have been an ASYNC or
1282 * NO_PREROLL element */
1283 ret = GST_STATE_RETURN (element);
1284 GST_DEBUG_OBJECT (bin, "added %s element",
1285 gst_element_state_change_return_get_name (ret));
1288 case GST_STATE_CHANGE_ASYNC:
1290 /* create message to track this aync element when it posts an async-done
1292 async_message = gst_message_new_async_start (GST_OBJECT_CAST (element));
1295 case GST_STATE_CHANGE_NO_PREROLL:
1296 /* ignore all async elements we might have and commit our state */
1297 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1299 case GST_STATE_CHANGE_FAILURE:
1306 GST_OBJECT_UNLOCK (bin);
1308 for (l = need_context_messages; l; l = l->next) {
1309 GstMessage *msg = l->data;
1311 const gchar *context_type;
1312 GstContext *replacement, *context;
1314 gst_message_parse_context_type (msg, &context_type);
1316 GST_LOG_OBJECT (bin, "asking parent for context type: %s "
1317 "from %" GST_PTR_FORMAT, context_type, element);
1319 s = (GstStructure *) gst_message_get_structure (msg);
1320 gst_structure_get (s, "bin.old.context", GST_TYPE_CONTEXT, &context, NULL);
1321 gst_structure_remove_field (s, "bin.old.context");
1322 /* Keep the msg around while we still need access to the context_type */
1323 gst_element_post_message (GST_ELEMENT_CAST (bin), gst_message_ref (msg));
1325 /* lock to avoid losing a potential write */
1326 GST_OBJECT_LOCK (bin);
1328 gst_element_get_context_unlocked (GST_ELEMENT_CAST (bin), context_type);
1329 gst_message_unref (msg);
1332 /* we got the context set from GstElement::set_context */
1333 gst_context_unref (replacement);
1334 GST_OBJECT_UNLOCK (bin);
1336 /* Propagate the element's context upwards */
1337 GST_LOG_OBJECT (bin, "propagating existing context type: %s %p "
1338 "from %" GST_PTR_FORMAT, context_type, context, element);
1340 gst_bin_update_context_unlocked (bin, context);
1343 gst_message_new_have_context (GST_OBJECT_CAST (bin),
1344 gst_context_ref (context));
1345 GST_OBJECT_UNLOCK (bin);
1346 gst_element_post_message (GST_ELEMENT_CAST (bin), msg);
1348 gst_context_unref (context);
1350 g_list_free_full (elem_contexts, (GDestroyNotify) gst_context_unref);
1351 g_list_free (need_context_messages);
1353 /* post the messages on the bus of the element so that the bin can handle
1356 gst_element_post_message (element, clock_message);
1359 gst_element_post_message (element, async_message);
1361 /* unlink all linked pads */
1362 it = gst_element_iterate_pads (element);
1363 while (gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads,
1364 NULL) == GST_ITERATOR_RESYNC)
1365 gst_iterator_resync (it);
1366 gst_iterator_free (it);
1368 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
1371 g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
1372 gst_child_proxy_child_added ((GstChildProxy *) bin, (GObject *) element,
1375 gst_bin_do_deep_add_remove (bin, gst_bin_signals[DEEP_ELEMENT_ADDED],
1376 "deep-element-added", element);
1382 /* ERROR handling here */
1385 GST_OBJECT_LOCK (bin);
1386 g_warning ("Cannot add bin '%s' to itself", GST_ELEMENT_NAME (bin));
1387 GST_OBJECT_UNLOCK (bin);
1388 gst_object_ref_sink (element);
1389 gst_object_unref (element);
1394 g_warning ("Name '%s' is not unique in bin '%s', not adding",
1395 elem_name, GST_ELEMENT_NAME (bin));
1396 GST_OBJECT_UNLOCK (bin);
1398 gst_object_ref_sink (element);
1399 gst_object_unref (element);
1404 g_warning ("Element '%s' already has parent", elem_name);
1405 GST_OBJECT_UNLOCK (bin);
1412 * gst_bin_set_suppressed_flags:
1414 * @flags: the #GstElementFlags to suppress
1416 * Suppresses the given flags on the bin. #GstElementFlags of a
1417 * child element are propagated when it is added to the bin.
1418 * When suppressed flags are set, those specified flags will
1419 * not be propagated to the bin.
1424 gst_bin_set_suppressed_flags (GstBin * bin, GstElementFlags flags)
1426 g_return_if_fail (GST_IS_BIN (bin));
1428 GST_OBJECT_LOCK (bin);
1429 bin->priv->suppressed_flags = bin->priv->suppressed_flags | flags;
1430 GST_OBJECT_UNLOCK (bin);
1432 GST_DEBUG_OBJECT (bin, "Set suppressed flags(0x%x) to bin '%s'", flags,
1433 GST_ELEMENT_NAME (bin));
1437 * gst_bin_get_suppressed_flags:
1440 * Returns: the bin's suppressed #GstElementFlags.
1445 gst_bin_get_suppressed_flags (GstBin * bin)
1447 GstElementFlags res;
1449 g_return_val_if_fail (GST_IS_BIN (bin), 0);
1451 GST_OBJECT_LOCK (bin);
1452 res = bin->priv->suppressed_flags;
1453 GST_OBJECT_UNLOCK (bin);
1458 /* signal vfunc, will be called when a new element was added */
1460 gst_bin_deep_element_added_func (GstBin * bin, GstBin * sub_bin,
1465 parent_bin = (GstBin *) gst_object_get_parent (GST_OBJECT_CAST (bin));
1466 if (parent_bin == NULL) {
1467 GST_LOG_OBJECT (bin, "no parent, reached top-level");
1471 GST_LOG_OBJECT (parent_bin, "emitting deep-element-added for element "
1472 "%" GST_PTR_FORMAT " which has just been added to %" GST_PTR_FORMAT,
1475 g_signal_emit (parent_bin, gst_bin_signals[DEEP_ELEMENT_ADDED], 0, sub_bin,
1478 gst_object_unref (parent_bin);
1481 /* signal vfunc, will be called when an element was removed */
1483 gst_bin_deep_element_removed_func (GstBin * bin, GstBin * sub_bin,
1488 parent_bin = (GstBin *) gst_object_get_parent (GST_OBJECT_CAST (bin));
1489 if (parent_bin == NULL) {
1490 GST_LOG_OBJECT (bin, "no parent, reached top-level");
1494 GST_LOG_OBJECT (parent_bin, "emitting deep-element-removed for element "
1495 "%" GST_PTR_FORMAT " which has just been removed from %" GST_PTR_FORMAT,
1498 g_signal_emit (parent_bin, gst_bin_signals[DEEP_ELEMENT_REMOVED], 0, sub_bin,
1501 gst_object_unref (parent_bin);
1507 * @element: (transfer floating): the #GstElement to add
1509 * Adds the given element to the bin. Sets the element's parent, and thus
1510 * takes ownership of the element. An element can only be added to one bin.
1512 * If the element's pads are linked to other pads, the pads will be unlinked
1513 * before the element is added to the bin.
1515 * > When you add an element to an already-running pipeline, you will have to
1516 * > take care to set the state of the newly-added element to the desired
1517 * > state (usually PLAYING or PAUSED, same you set the pipeline to originally)
1518 * > with gst_element_set_state(), or use gst_element_sync_state_with_parent().
1519 * > The bin or pipeline will not take care of this for you.
1521 * Returns: %TRUE if the element could be added, %FALSE if
1522 * the bin does not want to accept the element.
1525 gst_bin_add (GstBin * bin, GstElement * element)
1527 GstBinClass *bclass;
1530 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1531 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1532 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1534 bclass = GST_BIN_GET_CLASS (bin);
1536 if (G_UNLIKELY (bclass->add_element == NULL))
1539 #ifndef TIZEN_PROFILE_TV
1540 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1541 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1542 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1544 gst_set_family_id_to_child (element, (GST_OBJECT_CAST (bin)->family_id));
1546 GST_CAT_DEBUG (GST_CAT_PARENTAGE,
1547 "adding element %s (id %d) to bin %s (id %d)",
1548 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1549 GST_OBJECT_CAST (element)->family_id,
1550 GST_STR_NULL (GST_ELEMENT_NAME (bin)), GST_OBJECT_CAST (bin)->family_id);
1553 GST_TRACER_BIN_ADD_PRE (bin, element);
1554 result = bclass->add_element (bin, element);
1555 GST_TRACER_BIN_ADD_POST (bin, element, result);
1559 /* ERROR handling */
1562 g_warning ("adding elements to bin '%s' is not supported",
1563 GST_ELEMENT_NAME (bin));
1564 gst_object_ref_sink (element);
1565 gst_object_unref (element);
1570 /* remove an element from the bin
1575 gst_bin_remove_func (GstBin * bin, GstElement * element)
1579 gboolean is_sink, is_source, provides_clock, requires_clock;
1580 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1581 GstMessage *clock_message = NULL;
1582 GstClock **provided_clock_p;
1583 GstElement **clock_provider_p;
1585 gboolean other_async, this_async, have_no_preroll, removed_eos;
1586 GstStateChangeReturn ret;
1588 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1590 /* we obviously can't remove ourself from ourself */
1591 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1592 goto removing_itself;
1594 GST_OBJECT_LOCK (bin);
1596 GST_OBJECT_LOCK (element);
1597 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1599 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1602 /* remove the parent ref */
1603 GST_OBJECT_PARENT (element) = NULL;
1605 /* grab element name so we can print it */
1606 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1607 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1609 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1611 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1612 GST_OBJECT_UNLOCK (element);
1616 othersource = FALSE;
1617 otherprovider = FALSE;
1618 otherrequirer = FALSE;
1619 have_no_preroll = FALSE;
1620 /* iterate the elements, we collect which ones are async and no_preroll. We
1621 * also remove the element when we find it. */
1622 for (walk = bin->children; walk; walk = next) {
1623 GstElement *child = GST_ELEMENT_CAST (walk->data);
1625 next = g_list_next (walk);
1627 if (child == element) {
1629 /* remove the element */
1630 bin->children = g_list_delete_link (bin->children, walk);
1632 gboolean child_sink, child_source, child_provider, child_requirer;
1634 GST_OBJECT_LOCK (child);
1635 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1636 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1638 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1640 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1641 /* when we remove a sink, check if there are other sinks. */
1642 if (is_sink && !othersink && child_sink)
1644 if (is_source && !othersource && child_source)
1646 if (provides_clock && !otherprovider && child_provider)
1647 otherprovider = TRUE;
1648 if (requires_clock && !otherrequirer && child_requirer)
1649 otherrequirer = TRUE;
1650 /* check if we have NO_PREROLL children */
1651 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1652 have_no_preroll = TRUE;
1653 GST_OBJECT_UNLOCK (child);
1657 /* the element must have been in the bin's list of children */
1658 if (G_UNLIKELY (!found))
1661 /* we now removed the element from the list of elements, increment the cookie
1662 * so that others can detect a change in the children list. */
1664 bin->children_cookie++;
1665 if (!GST_BIN_IS_NO_RESYNC (bin))
1666 bin->priv->structure_cookie++;
1668 if (is_sink && !othersink
1669 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SINK)) {
1670 /* we're not a sink anymore */
1671 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1672 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1674 if (is_source && !othersource
1675 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SOURCE)) {
1676 /* we're not a source anymore */
1677 GST_DEBUG_OBJECT (bin, "we removed the last source");
1678 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1680 if (provides_clock && !otherprovider
1681 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_PROVIDE_CLOCK)) {
1682 /* we're not a clock provider anymore */
1683 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1684 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1686 if (requires_clock && !otherrequirer
1687 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_REQUIRE_CLOCK)) {
1688 /* we're not a clock requirer anymore */
1689 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1690 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1693 /* if the clock provider for this element is removed, we lost
1694 * the clock as well, we need to inform the parent of this
1695 * so that it can select a new clock */
1696 if (bin->clock_provider == element) {
1697 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1698 bin->clock_dirty = TRUE;
1700 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1701 provided_clock_p = &bin->provided_clock;
1702 clock_provider_p = &bin->clock_provider;
1703 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1704 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1707 /* remove messages for the element, if there was a pending ASYNC_START
1708 * message we must see if removing the element caused the bin to lose its
1711 other_async = FALSE;
1712 /* If we remove an EOSed element, the bin might go EOS */
1713 removed_eos = FALSE;
1714 for (walk = bin->messages; walk; walk = next) {
1715 GstMessage *message = (GstMessage *) walk->data;
1716 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1719 next = g_list_next (walk);
1722 switch (GST_MESSAGE_TYPE (message)) {
1723 case GST_MESSAGE_ASYNC_START:
1729 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1731 case GST_MESSAGE_STRUCTURE_CHANGE:
1735 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1737 /* it's unlikely that this message is still in the list of messages
1738 * because this would mean that a link/unlink is busy in another thread
1739 * while we remove the element. We still have to remove the message
1740 * because we might not receive the done message anymore when the element
1741 * is removed from the bin. */
1742 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1743 if (owner == element)
1747 case GST_MESSAGE_EOS:
1758 /* delete all message types */
1759 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1760 message, elem_name);
1761 bin->messages = g_list_delete_link (bin->messages, walk);
1762 gst_message_unref (message);
1766 /* get last return */
1767 ret = GST_STATE_RETURN (bin);
1769 /* no need to update the state if we are in error */
1770 if (ret == GST_STATE_CHANGE_FAILURE)
1771 goto no_state_recalc;
1773 if (!other_async && this_async) {
1774 /* all other elements were not async and we removed the async one,
1775 * handle the async-done case because we are not async anymore now. */
1776 GST_DEBUG_OBJECT (bin,
1777 "we removed the last async element, have no_preroll %d",
1780 /* the current state return of the bin depends on if there are no_preroll
1781 * elements in the pipeline or not */
1782 if (have_no_preroll)
1783 ret = GST_STATE_CHANGE_NO_PREROLL;
1785 ret = GST_STATE_CHANGE_SUCCESS;
1787 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1789 GST_DEBUG_OBJECT (bin,
1790 "recalc state preroll: %d, other async: %d, this async %d",
1791 have_no_preroll, other_async, this_async);
1793 if (have_no_preroll) {
1794 ret = GST_STATE_CHANGE_NO_PREROLL;
1795 } else if (other_async) {
1796 /* there are other async elements and we were not doing an async state
1797 * change, change our pending state and go async */
1798 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1799 GST_STATE_NEXT (bin) = GST_STATE (bin);
1800 GST_STATE_PENDING (bin) = GST_STATE (bin);
1802 ret = GST_STATE_CHANGE_ASYNC;
1804 GST_STATE_RETURN (bin) = ret;
1808 gst_element_set_bus (element, NULL);
1809 /* Clear the clock we provided to the element */
1810 gst_element_set_clock (element, NULL);
1811 GST_OBJECT_UNLOCK (bin);
1813 /* If the element was a sink that had not posted EOS,
1814 * it might have been the last one we were waiting for,
1815 * so check if it's time to send EOS now */
1816 if (is_sink && !removed_eos) {
1817 GST_DEBUG_OBJECT (bin,
1818 "Removing sink that had not EOSed. Re-checking overall EOS status");
1823 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1825 /* unlink all linked pads */
1826 it = gst_element_iterate_pads (element);
1827 while (gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads,
1828 NULL) == GST_ITERATOR_RESYNC)
1829 gst_iterator_resync (it);
1830 gst_iterator_free (it);
1832 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1835 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1836 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1839 gst_bin_do_deep_add_remove (bin, gst_bin_signals[DEEP_ELEMENT_REMOVED],
1840 "deep-element-removed", element);
1843 /* element is really out of our control now */
1844 gst_object_unref (element);
1848 /* ERROR handling */
1851 GST_OBJECT_LOCK (bin);
1852 g_warning ("Cannot remove bin '%s' from itself", GST_ELEMENT_NAME (bin));
1853 GST_OBJECT_UNLOCK (bin);
1858 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1859 GST_ELEMENT_NAME (bin));
1860 GST_OBJECT_UNLOCK (element);
1861 GST_OBJECT_UNLOCK (bin);
1870 * @element: (transfer none): the #GstElement to remove
1872 * Removes the element from the bin, unparenting it as well.
1873 * Unparenting the element means that the element will be dereferenced,
1874 * so if the bin holds the only reference to the element, the element
1875 * will be freed in the process of removing it from the bin. If you
1876 * want the element to still exist after removing, you need to call
1877 * gst_object_ref() before removing it from the bin.
1879 * If the element's pads are linked to other pads, the pads will be unlinked
1880 * before the element is removed from the bin.
1882 * Returns: %TRUE if the element could be removed, %FALSE if
1883 * the bin does not want to remove the element.
1886 gst_bin_remove (GstBin * bin, GstElement * element)
1888 GstBinClass *bclass;
1891 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1892 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1893 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1895 bclass = GST_BIN_GET_CLASS (bin);
1897 if (G_UNLIKELY (bclass->remove_element == NULL))
1900 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1901 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1903 GST_TRACER_BIN_REMOVE_PRE (bin, element);
1904 result = bclass->remove_element (bin, element);
1905 GST_TRACER_BIN_REMOVE_POST (bin, result);
1909 /* ERROR handling */
1912 g_warning ("removing elements from bin '%s' is not supported",
1913 GST_ELEMENT_NAME (bin));
1919 * gst_bin_iterate_elements:
1922 * Gets an iterator for the elements in this bin.
1924 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
1927 gst_bin_iterate_elements (GstBin * bin)
1929 GstIterator *result;
1931 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1933 GST_OBJECT_LOCK (bin);
1934 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1935 GST_OBJECT_GET_LOCK (bin),
1936 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1937 GST_OBJECT_UNLOCK (bin);
1942 static GstIteratorItem
1943 iterate_child_recurse (GstIterator * it, const GValue * item)
1945 GstElement *child = g_value_get_object (item);
1947 if (GST_IS_BIN (child)) {
1948 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1950 gst_iterator_push (it, other);
1952 return GST_ITERATOR_ITEM_PASS;
1956 * gst_bin_iterate_recurse:
1959 * Gets an iterator for the elements in this bin.
1960 * This iterator recurses into GstBin children.
1962 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
1965 gst_bin_iterate_recurse (GstBin * bin)
1967 GstIterator *result;
1969 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1971 GST_OBJECT_LOCK (bin);
1972 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1973 GST_OBJECT_GET_LOCK (bin),
1974 &bin->children_cookie,
1976 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1977 GST_OBJECT_UNLOCK (bin);
1982 /* returns 0 when TRUE because this is a GCompareFunc */
1985 bin_element_is_sink (GstElement * child, GstBin * bin)
1989 /* we lock the child here for the remainder of the function to
1990 * get its name and flag safely. */
1991 GST_OBJECT_LOCK (child);
1992 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1994 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1995 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1997 GST_OBJECT_UNLOCK (child);
1998 return is_sink ? 0 : 1;
2002 sink_iterator_filter (const GValue * vchild, GValue * vbin)
2004 GstBin *bin = g_value_get_object (vbin);
2005 GstElement *child = g_value_get_object (vchild);
2007 return (bin_element_is_sink (child, bin));
2011 * gst_bin_iterate_sinks:
2014 * Gets an iterator for all elements in the bin that have the
2015 * #GST_ELEMENT_FLAG_SINK flag set.
2017 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
2020 gst_bin_iterate_sinks (GstBin * bin)
2022 GstIterator *children;
2023 GstIterator *result;
2024 GValue vbin = { 0, };
2026 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2028 g_value_init (&vbin, GST_TYPE_BIN);
2029 g_value_set_object (&vbin, bin);
2031 children = gst_bin_iterate_elements (bin);
2032 result = gst_iterator_filter (children,
2033 (GCompareFunc) sink_iterator_filter, &vbin);
2035 g_value_unset (&vbin);
2040 /* returns 0 when TRUE because this is a GCompareFunc */
2043 bin_element_is_src (GstElement * child, GstBin * bin)
2047 /* we lock the child here for the remainder of the function to
2048 * get its name and other info safely. */
2049 GST_OBJECT_LOCK (child);
2050 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
2052 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2053 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
2055 GST_OBJECT_UNLOCK (child);
2056 return is_src ? 0 : 1;
2060 src_iterator_filter (const GValue * vchild, GValue * vbin)
2062 GstBin *bin = g_value_get_object (vbin);
2063 GstElement *child = g_value_get_object (vchild);
2065 return (bin_element_is_src (child, bin));
2069 * gst_bin_iterate_sources:
2072 * Gets an iterator for all elements in the bin that have the
2073 * #GST_ELEMENT_FLAG_SOURCE flag set.
2075 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
2078 gst_bin_iterate_sources (GstBin * bin)
2080 GstIterator *children;
2081 GstIterator *result;
2082 GValue vbin = { 0, };
2084 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2086 g_value_init (&vbin, GST_TYPE_BIN);
2087 g_value_set_object (&vbin, bin);
2089 children = gst_bin_iterate_elements (bin);
2090 result = gst_iterator_filter (children,
2091 (GCompareFunc) src_iterator_filter, &vbin);
2093 g_value_unset (&vbin);
2101 static GstStateChangeReturn
2102 gst_bin_get_state_func (GstElement * element, GstState * state,
2103 GstState * pending, GstClockTime timeout)
2105 GstStateChangeReturn ret;
2107 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
2110 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
2116 /***********************************************
2117 * Topologically sorted iterator
2118 * see http://en.wikipedia.org/wiki/Topological_sorting
2120 * For each element in the graph, an entry is kept in a HashTable
2121 * with its number of srcpad connections (degree).
2122 * We then change state of all elements without dependencies
2123 * (degree 0) and decrement the degree of all elements connected
2124 * on the sinkpads. When an element reaches degree 0, its state is
2126 * When all elements are handled the algorithm stops.
2128 typedef struct _GstBinSortIterator
2131 GQueue queue; /* elements queued for state change */
2132 GstBin *bin; /* bin we iterate */
2133 gint mode; /* adding or removing dependency */
2134 GstElement *best; /* next element with least dependencies */
2135 gint best_deg; /* best degree */
2136 GHashTable *hash; /* hashtable with element dependencies */
2137 gboolean dirty; /* we detected structure change */
2138 } GstBinSortIterator;
2141 copy_to_queue (gpointer data, gpointer user_data)
2143 GstElement *element = data;
2144 GQueue *queue = user_data;
2146 gst_object_ref (element);
2147 g_queue_push_tail (queue, element);
2151 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
2152 GstBinSortIterator * copy)
2154 GHashTableIter iter;
2155 gpointer key, value;
2157 g_queue_init (©->queue);
2158 g_queue_foreach ((GQueue *) & it->queue, copy_to_queue, ©->queue);
2160 copy->bin = gst_object_ref (it->bin);
2162 copy->best = gst_object_ref (it->best);
2164 copy->hash = g_hash_table_new (NULL, NULL);
2165 g_hash_table_iter_init (&iter, it->hash);
2166 while (g_hash_table_iter_next (&iter, &key, &value))
2167 g_hash_table_insert (copy->hash, key, value);
2170 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
2171 #define HASH_SET_DEGREE(bit, elem, deg) \
2172 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
2173 #define HASH_GET_DEGREE(bit, elem) \
2174 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
2176 /* add element to queue of next elements in the iterator.
2177 * We push at the tail to give higher priority elements a
2180 add_to_queue (GstBinSortIterator * bit, GstElement * element)
2182 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
2183 GST_ELEMENT_NAME (element));
2184 gst_object_ref (element);
2185 g_queue_push_tail (&bit->queue, element);
2186 HASH_SET_DEGREE (bit, element, -1);
2190 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
2194 if ((find = g_queue_find (&bit->queue, element))) {
2195 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
2196 GST_ELEMENT_NAME (element));
2198 g_queue_delete_link (&bit->queue, find);
2199 gst_object_unref (element);
2201 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
2202 GST_ELEMENT_NAME (element));
2206 /* clear the queue, unref all objects as we took a ref when
2207 * we added them to the queue */
2209 clear_queue (GQueue * queue)
2213 while ((p = g_queue_pop_head (queue)))
2214 gst_object_unref (p);
2217 /* set all degrees to 0. Elements marked as a sink are
2218 * added to the queue immediately. Since we only look at the SINK flag of the
2219 * element, it is possible that we add non-sinks to the queue. These will be
2220 * removed from the queue again when we can prove that it provides data for some
2223 reset_degree (GstElement * element, GstBinSortIterator * bit)
2227 /* sinks are added right away */
2228 GST_OBJECT_LOCK (element);
2229 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
2230 GST_OBJECT_UNLOCK (element);
2233 add_to_queue (bit, element);
2235 /* others are marked with 0 and handled when sinks are done */
2236 HASH_SET_DEGREE (bit, element, 0);
2240 /* adjust the degree of all elements connected to the given
2241 * element. If a degree of an element drops to 0, it is
2242 * added to the queue of elements to schedule next.
2244 * We have to make sure not to cross the bin boundary this element
2248 update_degree (GstElement * element, GstBinSortIterator * bit)
2250 gboolean linked = FALSE;
2252 GST_OBJECT_LOCK (element);
2253 /* don't touch degree if element has no sinkpads */
2254 if (element->numsinkpads != 0) {
2255 /* loop over all sinkpads, decrement degree for all connected
2256 * elements in this bin */
2259 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
2262 pad = GST_PAD_CAST (pads->data);
2264 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
2265 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
2266 GST_MESSAGE_STRUCTURE_CHANGE))) {
2267 /* mark the iterator as dirty because we won't be updating the degree
2268 * of the peer parent now. This would result in the 'loop detected'
2269 * later on because the peer parent element could become the best next
2270 * element with a degree > 0. We will simply continue our state
2271 * changes and we'll eventually resync when the unlink completed and
2272 * the iterator cookie is updated. */
2277 if ((peer = gst_pad_get_peer (pad))) {
2278 GstElement *peer_element;
2280 if ((peer_element = gst_pad_get_parent_element (peer))) {
2281 GST_OBJECT_LOCK (peer_element);
2282 /* check that we don't go outside of this bin */
2283 if (GST_OBJECT_CAST (peer_element)->parent ==
2284 GST_OBJECT_CAST (bit->bin)) {
2285 gint old_deg, new_deg;
2287 old_deg = HASH_GET_DEGREE (bit, peer_element);
2289 /* check to see if we added an element as sink that was not really a
2290 * sink because it was connected to some other element. */
2291 if (old_deg == -1) {
2292 remove_from_queue (bit, peer_element);
2295 new_deg = old_deg + bit->mode;
2297 GST_DEBUG_OBJECT (bit->bin,
2298 "change element %s, degree %d->%d, linked to %s",
2299 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
2300 GST_ELEMENT_NAME (element));
2302 /* update degree, it is possible that an element was in 0 and
2303 * reaches -1 here. This would mean that the element had no sinkpads
2304 * but became linked while the state change was happening. We will
2305 * resync on this with the structure change message. */
2307 /* degree hit 0, add to queue */
2308 add_to_queue (bit, peer_element);
2310 HASH_SET_DEGREE (bit, peer_element, new_deg);
2314 GST_OBJECT_UNLOCK (peer_element);
2315 gst_object_unref (peer_element);
2317 gst_object_unref (peer);
2322 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2323 GST_ELEMENT_NAME (element));
2325 GST_OBJECT_UNLOCK (element);
2328 /* find the next best element not handled yet. This is the one
2329 * with the lowest non-negative degree */
2331 find_element (GstElement * element, GstBinSortIterator * bit)
2335 /* element is already handled */
2336 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2339 /* first element or element with smaller degree */
2340 if (bit->best == NULL || bit->best_deg > degree) {
2341 bit->best = element;
2342 bit->best_deg = degree;
2343 } else if (bit->best_deg == degree
2344 && GST_OBJECT_FLAG_IS_SET (bit->best, GST_ELEMENT_FLAG_SOURCE)
2345 && !GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE)) {
2346 /* If two elements have the same degree, we want to ensure we
2347 * return non-source elements first. */
2348 bit->best = element;
2352 /* get next element in iterator. */
2353 static GstIteratorResult
2354 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2357 GstBin *bin = bit->bin;
2359 /* empty queue, we have to find a next best element */
2360 if (g_queue_is_empty (&bit->queue)) {
2362 bit->best_deg = G_MAXINT;
2363 g_list_foreach (bin->children, (GFunc) find_element, bit);
2364 if ((best = bit->best)) {
2365 /* when we detected an unlink, don't warn because our degrees might be
2366 * screwed up. We will resync later */
2367 if (bit->best_deg != 0 && !bit->dirty) {
2368 /* we don't fail on this one yet */
2369 GST_WARNING_OBJECT (bin, "loop dected in graph");
2370 g_warning ("loop detected in the graph of bin '%s'!!",
2371 GST_ELEMENT_NAME (bin));
2373 /* best unhandled element, schedule as next element */
2374 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2375 GST_ELEMENT_NAME (best));
2376 HASH_SET_DEGREE (bit, best, -1);
2377 g_value_set_object (result, best);
2379 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2380 /* no more unhandled elements, we are done */
2381 return GST_ITERATOR_DONE;
2384 /* everything added to the queue got reffed */
2385 best = g_queue_pop_head (&bit->queue);
2386 g_value_set_object (result, best);
2387 gst_object_unref (best);
2390 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2391 /* update degrees of linked elements */
2392 update_degree (best, bit);
2394 return GST_ITERATOR_OK;
2397 /* clear queues, recalculate the degrees and restart. */
2399 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2401 GstBin *bin = bit->bin;
2403 GST_DEBUG_OBJECT (bin, "resync");
2405 clear_queue (&bit->queue);
2407 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2408 /* calc degrees, incrementing */
2410 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2411 /* for the rest of the function we decrement the degrees */
2415 /* clear queues, unref bin and free iterator. */
2417 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2419 GstBin *bin = bit->bin;
2421 GST_DEBUG_OBJECT (bin, "free");
2422 clear_queue (&bit->queue);
2423 g_hash_table_destroy (bit->hash);
2424 gst_object_unref (bin);
2427 /* should be called with the bin LOCK held */
2428 static GstIterator *
2429 gst_bin_sort_iterator_new (GstBin * bin)
2431 GstBinSortIterator *result;
2433 /* we don't need an ItemFunction because we ref the items in the _next
2435 result = (GstBinSortIterator *)
2436 gst_iterator_new (sizeof (GstBinSortIterator),
2438 GST_OBJECT_GET_LOCK (bin),
2439 &bin->priv->structure_cookie,
2440 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2441 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2442 (GstIteratorItemFunction) NULL,
2443 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2444 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2445 g_queue_init (&result->queue);
2446 result->hash = g_hash_table_new (NULL, NULL);
2447 gst_object_ref (bin);
2449 gst_bin_sort_iterator_resync (result);
2451 return (GstIterator *) result;
2455 * gst_bin_iterate_sorted:
2458 * Gets an iterator for the elements in this bin in topologically
2459 * sorted order. This means that the elements are returned from
2460 * the most downstream elements (sinks) to the sources.
2462 * This function is used internally to perform the state changes
2463 * of the bin elements and for clock selection.
2465 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
2468 gst_bin_iterate_sorted (GstBin * bin)
2470 GstIterator *result;
2472 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2474 GST_OBJECT_LOCK (bin);
2475 result = gst_bin_sort_iterator_new (bin);
2476 GST_OBJECT_UNLOCK (bin);
2481 static GstStateChangeReturn
2482 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2483 GstClockTime base_time, GstClockTime start_time, GstState current,
2486 GstStateChangeReturn ret;
2487 GstState child_current, child_pending;
2491 GST_STATE_LOCK (element);
2493 GST_OBJECT_LOCK (element);
2494 /* set base_time and start time on child */
2495 GST_ELEMENT_START_TIME (element) = start_time;
2496 element->base_time = base_time;
2497 /* peel off the locked flag */
2498 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2499 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2500 ret = GST_STATE_RETURN (element);
2501 child_current = GST_STATE (element);
2502 child_pending = GST_STATE_PENDING (element);
2503 GST_OBJECT_UNLOCK (element);
2505 /* skip locked elements */
2506 if (G_UNLIKELY (locked))
2509 /* if the element was no preroll, just start changing the state regardless
2510 * if it had async elements (in the case of a bin) because they won't preroll
2512 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2513 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2517 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2518 "current %s pending %s, desired next %s",
2519 gst_element_state_get_name (child_current),
2520 gst_element_state_get_name (child_pending),
2521 gst_element_state_get_name (next));
2523 /* always recurse into bins so that we can set the base time */
2524 if (GST_IS_BIN (element))
2527 /* Try not to change the state of elements that are already in the state we're
2529 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2530 /* child is already at the requested state, return previous return. Note that
2531 * if the child has a pending state to next, we will still call the
2532 * set_state function */
2534 } else if (next > current) {
2535 /* upward state change */
2536 if (child_pending == GST_STATE_VOID_PENDING) {
2537 /* .. and the child is not busy doing anything */
2538 if (child_current > next) {
2539 /* .. and is already past the requested state, assume it got there
2541 ret = GST_STATE_CHANGE_SUCCESS;
2544 } else if (child_pending > child_current) {
2545 /* .. and the child is busy going upwards */
2546 if (child_current >= next) {
2547 /* .. and is already past the requested state, assume it got there
2549 ret = GST_STATE_CHANGE_SUCCESS;
2553 /* .. and the child is busy going downwards */
2554 if (child_current > next) {
2555 /* .. and is already past the requested state, assume it got there
2557 ret = GST_STATE_CHANGE_SUCCESS;
2561 } else if (next < current) {
2562 /* downward state change */
2563 if (child_pending == GST_STATE_VOID_PENDING) {
2564 /* .. and the child is not busy doing anything */
2565 if (child_current < next) {
2566 /* .. and is already past the requested state, assume it got there
2568 ret = GST_STATE_CHANGE_SUCCESS;
2571 } else if (child_pending < child_current) {
2572 /* .. and the child is busy going downwards */
2573 if (child_current <= next) {
2574 /* .. and is already past the requested state, assume it got there
2576 ret = GST_STATE_CHANGE_SUCCESS;
2580 /* .. and the child is busy going upwards */
2581 if (child_current < next) {
2582 /* .. and is already past the requested state, assume it got there
2584 ret = GST_STATE_CHANGE_SUCCESS;
2591 GST_OBJECT_LOCK (bin);
2592 /* the element was busy with an upwards async state change, we must wait for
2593 * an ASYNC_DONE message before we attempt to change the state. */
2595 find_message (bin, GST_OBJECT_CAST (element),
2596 GST_MESSAGE_ASYNC_START))) {
2597 #ifndef GST_DISABLE_GST_DEBUG
2598 GstMessage *message = GST_MESSAGE_CAST (found->data);
2600 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2601 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2603 /* only wait for upward state changes */
2604 if (next > current) {
2605 /* We found an async element check if we can force its state to change or
2606 * if we have to wait for it to preroll. */
2610 GST_OBJECT_UNLOCK (bin);
2613 GST_DEBUG_OBJECT (bin,
2614 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2615 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2616 GST_TIME_ARGS (base_time));
2619 ret = gst_element_set_state (element, next);
2621 GST_STATE_UNLOCK (element);
2627 GST_DEBUG_OBJECT (element,
2628 "element is locked, return previous return %s",
2629 gst_element_state_change_return_get_name (ret));
2630 GST_STATE_UNLOCK (element);
2635 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2636 "skipping transition from %s to %s",
2637 gst_element_state_get_name (child_current),
2638 gst_element_state_get_name (next));
2639 GST_STATE_UNLOCK (element);
2644 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2645 GST_OBJECT_UNLOCK (bin);
2646 GST_STATE_UNLOCK (element);
2647 return GST_STATE_CHANGE_ASYNC;
2651 /* gst_iterator_fold functions for pads_activate
2652 * Stop the iterator if activating one pad failed, but only if that pad
2653 * has not been removed from the element. */
2655 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2657 GstPad *pad = g_value_get_object (vpad);
2658 gboolean cont = TRUE;
2660 if (!gst_pad_set_active (pad, *active)) {
2661 if (GST_PAD_PARENT (pad) != NULL) {
2663 g_value_set_boolean (ret, FALSE);
2670 /* returns false on error or early cutout of the fold, true if all
2671 * pads in @iter were (de)activated successfully. */
2673 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2675 GstIteratorResult ires;
2678 /* no need to unset this later, it's just a boolean */
2679 g_value_init (&ret, G_TYPE_BOOLEAN);
2680 g_value_set_boolean (&ret, TRUE);
2683 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2686 case GST_ITERATOR_RESYNC:
2687 /* need to reset the result again */
2688 g_value_set_boolean (&ret, TRUE);
2689 gst_iterator_resync (iter);
2691 case GST_ITERATOR_DONE:
2692 /* all pads iterated, return collected value */
2695 /* iterator returned _ERROR or premature end with _OK,
2696 * mark an error and exit */
2697 g_value_set_boolean (&ret, FALSE);
2702 /* return collected value */
2703 return g_value_get_boolean (&ret);
2706 /* is called with STATE_LOCK
2709 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2714 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2716 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2717 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2718 gst_iterator_free (iter);
2719 if (G_UNLIKELY (!fold_ok))
2722 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2729 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2735 * gst_bin_recalculate_latency:
2738 * Queries @bin for the current latency and reconfigures this latency on all the
2739 * elements using a LATENCY event.
2741 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2742 * is posted on the bus.
2744 * This function simply emits the #GstBin::do-latency signal so any custom latency
2745 * calculations will be performed.
2747 * Returns: %TRUE if the latency could be queried and reconfigured.
2750 gst_bin_recalculate_latency (GstBin * bin)
2754 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2755 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2761 gst_bin_do_latency_func (GstBin * bin)
2764 GstElement *element;
2765 GstClockTime min_latency, max_latency;
2768 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2770 element = GST_ELEMENT_CAST (bin);
2772 GST_DEBUG_OBJECT (element, "querying latency");
2774 query = gst_query_new_latency ();
2775 if ((res = gst_element_query (element, query))) {
2778 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2780 GST_DEBUG_OBJECT (element,
2781 "got min latency %" GST_TIME_FORMAT ", max latency %"
2782 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2783 GST_TIME_ARGS (max_latency), live);
2785 if (max_latency < min_latency) {
2786 /* this is an impossible situation, some parts of the pipeline might not
2787 * work correctly. We post a warning for now. */
2788 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2789 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2790 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2791 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2794 /* configure latency on elements */
2795 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2797 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2798 GST_TIME_ARGS (min_latency));
2800 GST_WARNING_OBJECT (element,
2801 "did not really configure latency of %" GST_TIME_FORMAT,
2802 GST_TIME_ARGS (min_latency));
2805 /* this is not a real problem, we just don't configure any latency. */
2806 GST_WARNING_OBJECT (element, "failed to query latency");
2808 gst_query_unref (query);
2814 gst_bin_post_message (GstElement * element, GstMessage * msg)
2816 GstElementClass *pklass = (GstElementClass *) parent_class;
2819 ret = pklass->post_message (element, gst_message_ref (msg));
2821 if (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_STATE_CHANGED &&
2822 GST_MESSAGE_SRC (msg) == GST_OBJECT_CAST (element)) {
2823 GstState newstate, pending;
2825 gst_message_parse_state_changed (msg, NULL, &newstate, &pending);
2826 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING) {
2827 GST_BIN_CAST (element)->priv->posted_playing = TRUE;
2828 bin_do_eos (GST_BIN_CAST (element));
2830 GST_BIN_CAST (element)->priv->posted_playing = FALSE;
2834 gst_message_unref (msg);
2840 reset_state (const GValue * data, gpointer user_data)
2842 GstElement *e = g_value_get_object (data);
2843 GstState state = GPOINTER_TO_INT (user_data);
2845 if (gst_element_set_state (e, state) == GST_STATE_CHANGE_FAILURE)
2846 GST_WARNING_OBJECT (e, "Failed to switch back down to %s",
2847 gst_element_state_get_name (state));
2850 static GstStateChangeReturn
2851 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2854 GstStateChangeReturn ret;
2855 GstState current, next;
2856 gboolean have_async;
2857 gboolean have_no_preroll;
2858 GstClockTime base_time, start_time;
2861 GValue data = { 0, };
2863 /* we don't need to take the STATE_LOCK, it is already taken */
2864 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2865 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2867 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2868 "changing state of children from %s to %s",
2869 gst_element_state_get_name (current), gst_element_state_get_name (next));
2871 bin = GST_BIN_CAST (element);
2874 case GST_STATE_PLAYING:
2876 gboolean toplevel, asynchandling;
2878 GST_OBJECT_LOCK (bin);
2879 toplevel = BIN_IS_TOPLEVEL (bin);
2880 asynchandling = bin->priv->asynchandling;
2881 GST_OBJECT_UNLOCK (bin);
2884 gst_bin_recalculate_latency (bin);
2886 gst_element_post_message (element,
2887 gst_message_new_latency (GST_OBJECT_CAST (element)));
2890 case GST_STATE_PAUSED:
2891 /* Clear EOS list on next PAUSED */
2892 GST_OBJECT_LOCK (bin);
2893 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2894 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2895 bin->priv->posted_eos = FALSE;
2896 if (current == GST_STATE_READY)
2897 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2898 GST_OBJECT_UNLOCK (bin);
2899 if (current == GST_STATE_READY)
2900 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2901 goto activate_failure;
2903 case GST_STATE_READY:
2904 /* Clear message list on next READY */
2905 GST_OBJECT_LOCK (bin);
2906 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2907 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2908 GST_OBJECT_UNLOCK (bin);
2909 /* We might not have reached PAUSED yet due to async errors,
2910 * make sure to always deactivate the pads nonetheless */
2911 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2912 goto activate_failure;
2914 case GST_STATE_NULL:
2915 /* Clear message list on next NULL */
2916 GST_OBJECT_LOCK (bin);
2917 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2918 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2919 GST_OBJECT_UNLOCK (bin);
2920 if (current == GST_STATE_READY) {
2921 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2922 goto activate_failure;
2929 /* this flag is used to make the async state changes return immediately. We
2930 * don't want them to interfere with this state change */
2931 GST_OBJECT_LOCK (bin);
2932 bin->polling = TRUE;
2933 GST_OBJECT_UNLOCK (bin);
2935 /* iterate in state change order */
2936 it = gst_bin_iterate_sorted (bin);
2938 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2939 * Note how we don't reset this value when a resync happens, the reason being
2940 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2941 * even after a resync when the async element is gone */
2945 /* take base_time */
2946 base_time = gst_element_get_base_time (element);
2947 start_time = gst_element_get_start_time (element);
2949 have_no_preroll = FALSE;
2953 switch (gst_iterator_next (it, &data)) {
2954 case GST_ITERATOR_OK:
2958 child = g_value_get_object (&data);
2960 /* set state and base_time now */
2961 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2965 case GST_STATE_CHANGE_SUCCESS:
2966 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2967 "child '%s' changed state to %d(%s) successfully",
2968 GST_ELEMENT_NAME (child), next,
2969 gst_element_state_get_name (next));
2971 case GST_STATE_CHANGE_ASYNC:
2973 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2974 "child '%s' is changing state asynchronously to %s",
2975 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2979 case GST_STATE_CHANGE_FAILURE:{
2982 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2983 "child '%s' failed to go to state %d(%s)",
2984 GST_ELEMENT_NAME (child),
2985 next, gst_element_state_get_name (next));
2987 /* Only fail if the child is still inside
2988 * this bin. It might've been removed already
2989 * because of the error by the bin subclass
2990 * to ignore the error. */
2991 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2992 if (parent == GST_OBJECT_CAST (element)) {
2993 /* element is still in bin, really error now */
2994 gst_object_unref (parent);
2997 /* child removed from bin, let the resync code redo the state
2999 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
3000 "child '%s' was removed from the bin",
3001 GST_ELEMENT_NAME (child));
3004 gst_object_unref (parent);
3008 case GST_STATE_CHANGE_NO_PREROLL:
3009 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
3010 "child '%s' changed state to %d(%s) successfully without preroll",
3011 GST_ELEMENT_NAME (child), next,
3012 gst_element_state_get_name (next));
3013 have_no_preroll = TRUE;
3016 g_assert_not_reached ();
3019 g_value_reset (&data);
3022 case GST_ITERATOR_RESYNC:
3023 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
3024 gst_iterator_resync (it);
3027 case GST_ITERATOR_DONE:
3028 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
3034 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
3035 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
3038 if (have_no_preroll) {
3039 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3040 "we have NO_PREROLL elements %s -> NO_PREROLL",
3041 gst_element_state_change_return_get_name (ret));
3042 ret = GST_STATE_CHANGE_NO_PREROLL;
3043 } else if (have_async) {
3044 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3045 "we have ASYNC elements %s -> ASYNC",
3046 gst_element_state_change_return_get_name (ret));
3047 ret = GST_STATE_CHANGE_ASYNC;
3051 g_value_unset (&data);
3052 gst_iterator_free (it);
3054 GST_OBJECT_LOCK (bin);
3055 bin->polling = FALSE;
3056 /* it's possible that we did not get ASYNC from the children while the bin is
3057 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
3058 * itself as the source. In that case we still want to check if the state
3059 * change completed. */
3060 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
3061 /* no element returned ASYNC and there are no pending async_done messages,
3062 * we can just complete. */
3063 GST_DEBUG_OBJECT (bin, "no async elements");
3066 /* when we get here an ASYNC element was found */
3067 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
3068 /* we ignore ASYNC state changes when we go to READY or NULL */
3069 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
3070 gst_element_state_get_name (GST_STATE_TARGET (bin)));
3074 GST_DEBUG_OBJECT (bin, "check async elements");
3075 /* check if all elements managed to commit their state already */
3076 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3077 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
3078 * all the elements committed their state while we were doing the state
3079 * change. We will still return ASYNC for consistency but we commit the
3080 * state already so that a _get_state() will return immediately. */
3081 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3083 GST_DEBUG_OBJECT (bin, "async elements committed");
3084 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
3085 GST_CLOCK_TIME_NONE);
3089 bin->priv->pending_async_done = FALSE;
3090 GST_OBJECT_UNLOCK (bin);
3092 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
3093 "done changing bin's state from %s to %s, now in %s, ret %s",
3094 gst_element_state_get_name (current),
3095 gst_element_state_get_name (next),
3096 gst_element_state_get_name (GST_STATE (element)),
3097 gst_element_state_change_return_get_name (ret));
3104 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
3105 "failure (de)activating src pads");
3106 return GST_STATE_CHANGE_FAILURE;
3111 if (current < next) {
3112 GstIterator *it = gst_bin_iterate_sorted (GST_BIN (element));
3113 GstIteratorResult ret;
3115 GST_DEBUG_OBJECT (element,
3116 "Bin failed to change state, switching children back to %s",
3117 gst_element_state_get_name (current));
3120 gst_iterator_foreach (it, &reset_state, GINT_TO_POINTER (current));
3121 if (ret != GST_ITERATOR_RESYNC)
3123 gst_iterator_resync (it);
3125 gst_iterator_free (it);
3132 * This function is a utility event handler. It will send the event to all sinks
3133 * or sources and appropriate ghost pads depending on the event-direction.
3135 * Applications are free to override this behaviour and implement their own
3136 * handler, but this will work for pretty much all cases in practice.
3139 gst_bin_send_event (GstElement * element, GstEvent * event)
3141 GstBin *bin = GST_BIN_CAST (element);
3143 gboolean res = TRUE;
3144 gboolean done = FALSE;
3145 GValue data = { 0, };
3147 if (GST_EVENT_IS_DOWNSTREAM (event)) {
3148 iter = gst_bin_iterate_sources (bin);
3149 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
3150 GST_EVENT_TYPE_NAME (event));
3152 iter = gst_bin_iterate_sinks (bin);
3153 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
3154 GST_EVENT_TYPE_NAME (event));
3158 switch (gst_iterator_next (iter, &data)) {
3159 case GST_ITERATOR_OK:
3161 GstElement *child = g_value_get_object (&data);
3163 gst_event_ref (event);
3164 res &= gst_element_send_event (child, event);
3166 GST_LOG_OBJECT (child, "After handling %s event: %d",
3167 GST_EVENT_TYPE_NAME (event), res);
3169 g_value_reset (&data);
3172 case GST_ITERATOR_RESYNC:
3173 gst_iterator_resync (iter);
3176 case GST_ITERATOR_DONE:
3179 case GST_ITERATOR_ERROR:
3180 g_assert_not_reached ();
3184 g_value_unset (&data);
3185 gst_iterator_free (iter);
3187 if (GST_EVENT_IS_DOWNSTREAM (event)) {
3188 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
3189 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
3190 GST_EVENT_TYPE_NAME (event));
3192 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
3193 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
3194 GST_EVENT_TYPE_NAME (event));
3199 switch (gst_iterator_next (iter, &data)) {
3200 case GST_ITERATOR_OK:
3202 GstPad *pad = g_value_get_object (&data);
3204 gst_event_ref (event);
3205 res &= gst_pad_send_event (pad, event);
3206 GST_LOG_OBJECT (pad, "After handling %s event: %d",
3207 GST_EVENT_TYPE_NAME (event), res);
3210 case GST_ITERATOR_RESYNC:
3211 gst_iterator_resync (iter);
3214 case GST_ITERATOR_DONE:
3217 case GST_ITERATOR_ERROR:
3218 g_assert_not_reached ();
3223 g_value_unset (&data);
3224 gst_iterator_free (iter);
3225 gst_event_unref (event);
3230 /* this is the function called by the threadpool. When async elements commit
3231 * their state, this function will attempt to bring the bin to the next state.
3234 gst_bin_continue_func (GstBin * bin, BinContinueData * data)
3236 GstState current, next, pending;
3237 GstStateChange transition;
3239 pending = data->pending;
3241 GST_DEBUG_OBJECT (bin, "waiting for state lock");
3242 GST_STATE_LOCK (bin);
3244 GST_DEBUG_OBJECT (bin, "doing state continue");
3245 GST_OBJECT_LOCK (bin);
3247 /* if a new state change happened after this thread was scheduled, we return
3249 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
3252 current = GST_STATE (bin);
3253 next = GST_STATE_GET_NEXT (current, pending);
3254 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
3256 GST_STATE_NEXT (bin) = next;
3257 GST_STATE_PENDING (bin) = pending;
3259 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3260 GST_OBJECT_UNLOCK (bin);
3262 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3263 "continue state change %s to %s, final %s",
3264 gst_element_state_get_name (current),
3265 gst_element_state_get_name (next), gst_element_state_get_name (pending));
3267 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
3269 GST_STATE_UNLOCK (bin);
3270 GST_DEBUG_OBJECT (bin, "state continue done");
3276 GST_OBJECT_UNLOCK (bin);
3277 GST_STATE_UNLOCK (bin);
3278 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
3283 static GstBusSyncReply
3284 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
3286 GstBinClass *bclass;
3288 bclass = GST_BIN_GET_CLASS (bin);
3289 if (bclass->handle_message)
3290 bclass->handle_message (bin, message);
3292 gst_message_unref (message);
3294 return GST_BUS_DROP;
3298 free_bin_continue_data (BinContinueData * data)
3300 g_slice_free (BinContinueData, data);
3304 bin_push_state_continue (GstBin * bin, BinContinueData * data)
3306 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
3307 gst_element_call_async (GST_ELEMENT_CAST (bin),
3308 (GstElementCallAsyncFunc) gst_bin_continue_func, data,
3309 (GDestroyNotify) free_bin_continue_data);
3312 /* an element started an async state change, if we were not busy with a state
3313 * change, we perform a lost state.
3314 * This function is called with the OBJECT lock.
3317 bin_handle_async_start (GstBin * bin)
3319 GstState old_state, new_state;
3321 GstMessage *amessage = NULL;
3323 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3326 /* get our toplevel state */
3327 toplevel = BIN_IS_TOPLEVEL (bin);
3329 /* prepare an ASYNC_START message, we always post the start message even if we
3330 * are busy with a state change or when we are NO_PREROLL. */
3332 /* non toplevel bin, prepare async-start for the parent */
3333 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
3335 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
3338 /* async starts are ignored when we are NO_PREROLL */
3339 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
3340 goto was_no_preroll;
3342 old_state = GST_STATE (bin);
3344 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
3345 * PLAYING after optionally redistributing the base_time. */
3346 if (old_state > GST_STATE_PAUSED)
3347 new_state = GST_STATE_PAUSED;
3349 new_state = old_state;
3351 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3352 "lost state of %s, new %s", gst_element_state_get_name (old_state),
3353 gst_element_state_get_name (new_state));
3355 GST_STATE (bin) = new_state;
3356 GST_STATE_NEXT (bin) = new_state;
3357 GST_STATE_PENDING (bin) = new_state;
3358 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3359 GST_OBJECT_UNLOCK (bin);
3362 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
3367 /* post our ASYNC_START. */
3368 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
3369 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3371 GST_OBJECT_LOCK (bin);
3377 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3382 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3383 GST_OBJECT_UNLOCK (bin);
3388 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3389 GST_OBJECT_UNLOCK (bin);
3394 /* this function is called when there are no more async elements in the bin. We
3395 * post a state changed message and an ASYNC_DONE message.
3396 * This function is called with the OBJECT lock.
3399 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3400 gboolean flag_pending, GstClockTime running_time)
3402 GstState current, pending, target;
3403 GstStateChangeReturn old_ret;
3404 GstState old_state, old_next;
3405 gboolean toplevel, state_changed = FALSE;
3406 GstMessage *amessage = NULL;
3407 BinContinueData *cont = NULL;
3409 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3412 pending = GST_STATE_PENDING (bin);
3417 /* check if there is something to commit */
3418 if (pending == GST_STATE_VOID_PENDING)
3419 goto nothing_pending;
3421 old_ret = GST_STATE_RETURN (bin);
3422 GST_STATE_RETURN (bin) = ret;
3424 /* move to the next target state */
3425 target = GST_STATE_TARGET (bin);
3426 pending = GST_STATE_PENDING (bin) = target;
3428 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3430 old_state = GST_STATE (bin);
3431 /* this is the state we should go to next */
3432 old_next = GST_STATE_NEXT (bin);
3434 if (old_next != GST_STATE_PLAYING) {
3435 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3436 "committing state from %s to %s, old pending %s",
3437 gst_element_state_get_name (old_state),
3438 gst_element_state_get_name (old_next),
3439 gst_element_state_get_name (pending));
3441 /* update current state */
3442 current = GST_STATE (bin) = old_next;
3444 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3445 "setting state from %s to %s, pending %s",
3446 gst_element_state_get_name (old_state),
3447 gst_element_state_get_name (old_state),
3448 gst_element_state_get_name (pending));
3449 current = old_state;
3452 /* get our toplevel state */
3453 toplevel = BIN_IS_TOPLEVEL (bin);
3455 /* see if we reached the final state. If we are not toplevel, we also have to
3456 * stop here, the parent will continue our state. */
3457 if ((pending == current) || !toplevel) {
3458 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3459 "completed state change, pending VOID");
3461 /* mark VOID pending */
3462 pending = GST_STATE_VOID_PENDING;
3463 GST_STATE_PENDING (bin) = pending;
3464 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3466 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3467 "continue state change, pending %s",
3468 gst_element_state_get_name (pending));
3470 cont = g_slice_new (BinContinueData);
3472 /* cookie to detect concurrent state change */
3473 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3474 /* pending target state */
3475 cont->pending = pending;
3477 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3478 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3481 if (old_next != GST_STATE_PLAYING) {
3482 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3483 state_changed = TRUE;
3486 GST_OBJECT_UNLOCK (bin);
3488 if (state_changed) {
3489 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3493 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3494 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3495 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3498 GST_OBJECT_LOCK (bin);
3500 /* toplevel, start continue state */
3501 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3502 bin_push_state_continue (bin, cont);
3504 GST_DEBUG_OBJECT (bin, "state change complete");
3505 GST_STATE_BROADCAST (bin);
3511 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3516 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3517 /* if we were busy with a state change and we are requested to flag a
3518 * pending async done, we do so here */
3520 bin->priv->pending_async_done = TRUE;
3525 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3531 bin_do_eos (GstBin * bin)
3533 guint32 seqnum = GST_SEQNUM_INVALID;
3536 GST_OBJECT_LOCK (bin);
3537 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3538 * (or we're doing playing to playing and no one else will trigger posting
3539 * EOS for us) we forward the EOS message to the parent bin or application
3541 eos = GST_STATE (bin) == GST_STATE_PLAYING
3542 && (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING ||
3543 GST_STATE_PENDING (bin) == GST_STATE_PLAYING)
3544 && bin->priv->posted_playing && is_eos (bin, &seqnum);
3545 GST_OBJECT_UNLOCK (bin);
3548 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3550 GstMessage *tmessage;
3552 /* Clear out any further messages, and reset posted_eos so we can
3553 detect any new EOS that happens (eg, after a seek). Since all
3554 sinks have now posted an EOS, there will be no further EOS events
3555 seen unless there is a new logical EOS */
3556 GST_OBJECT_LOCK (bin);
3557 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3558 bin->priv->posted_eos = FALSE;
3559 GST_OBJECT_UNLOCK (bin);
3561 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3562 if (seqnum != GST_SEQNUM_INVALID)
3563 gst_message_set_seqnum (tmessage, seqnum);
3564 GST_DEBUG_OBJECT (bin,
3565 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3566 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3568 GST_LOG_OBJECT (bin, "Not forwarding EOS due to in progress state change, "
3569 " or already posted, or waiting for more EOS");
3574 bin_do_stream_start (GstBin * bin)
3576 guint32 seqnum = GST_SEQNUM_INVALID;
3577 gboolean stream_start;
3578 gboolean have_group_id = FALSE;
3581 GST_OBJECT_LOCK (bin);
3582 /* If all sinks are STREAM_START we forward the STREAM_START message
3583 * to the parent bin or application
3585 stream_start = is_stream_start (bin, &seqnum, &have_group_id, &group_id);
3586 GST_OBJECT_UNLOCK (bin);
3589 GstMessage *tmessage;
3591 GST_OBJECT_LOCK (bin);
3592 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3593 GST_OBJECT_UNLOCK (bin);
3595 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3596 if (seqnum != GST_SEQNUM_INVALID)
3597 gst_message_set_seqnum (tmessage, seqnum);
3599 gst_message_set_group_id (tmessage, group_id);
3601 GST_DEBUG_OBJECT (bin,
3602 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3604 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3608 /* must be called without the object lock as it posts messages */
3610 bin_do_message_forward (GstBin * bin, GstMessage * message)
3612 if (bin->priv->message_forward) {
3613 GstMessage *forwarded;
3615 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3616 GST_MESSAGE_TYPE_NAME (message));
3618 /* we need to convert these messages to element messages so that our parent
3619 * bin can easily ignore them and so that the application can easily
3620 * distinguish between the internally forwarded and the real messages. */
3621 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3622 gst_structure_new ("GstBinForwarded",
3623 "message", GST_TYPE_MESSAGE, message, NULL));
3625 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3630 gst_bin_update_context (GstBin * bin, GstContext * context)
3632 GST_OBJECT_LOCK (bin);
3633 gst_bin_update_context_unlocked (bin, context);
3634 GST_OBJECT_UNLOCK (bin);
3638 gst_bin_update_context_unlocked (GstBin * bin, GstContext * context)
3640 const gchar *context_type;
3641 GList *l, **contexts;
3643 contexts = &GST_ELEMENT_CAST (bin)->contexts;
3644 context_type = gst_context_get_context_type (context);
3646 GST_DEBUG_OBJECT (bin, "set context %p %" GST_PTR_FORMAT, context,
3647 gst_context_get_structure (context));
3648 for (l = *contexts; l; l = l->next) {
3649 GstContext *tmp = l->data;
3650 const gchar *tmp_type = gst_context_get_context_type (tmp);
3652 /* Always store newest context but never replace
3653 * a persistent one by a non-persistent one */
3654 if (strcmp (context_type, tmp_type) == 0 &&
3655 (gst_context_is_persistent (context) ||
3656 !gst_context_is_persistent (tmp))) {
3657 gst_context_replace ((GstContext **) & l->data, context);
3661 /* Not found? Add */
3663 *contexts = g_list_prepend (*contexts, gst_context_ref (context));
3667 /* handle child messages:
3669 * This method is called synchronously when a child posts a message on
3672 * GST_MESSAGE_EOS: This message is only posted by sinks
3673 * in the PLAYING state. If all sinks posted the EOS message, post
3676 * GST_MESSAGE_STATE_DIRTY: Deprecated
3678 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3679 * element posts segment_start twice, only the last message is kept.
3681 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3682 * with the segment_done message. If there are no more segment_start
3683 * messages, post segment_done message upwards.
3685 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3686 * can no longer provide a clock. The default bin behaviour is to
3687 * check if the lost clock was the one provided by the bin. If so and
3688 * we are currently in the PLAYING state, we forward the message to
3690 * This message is also generated when we remove a clock provider from
3691 * a bin. If this message is received by the application, it should
3692 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3693 * and a new base_time distribution.
3695 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3696 * can provide a clock. This mostly happens when we add a new clock
3697 * provider to the bin. The default behaviour of the bin is to mark the
3698 * currently selected clock as dirty, which will perform a clock
3699 * recalculation the next time we are asked to provide a clock.
3700 * This message is never sent to the application but is forwarded to
3703 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3704 * the state of the element and the fact that the element will need a
3705 * new base_time. This message is not forwarded to the application.
3707 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3708 * element when it posted ASYNC_START. If all elements are done, post a
3709 * ASYNC_DONE message to the parent.
3711 * OTHER: post upwards.
3714 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3717 GstMessageType type;
3718 GstMessage *tmessage;
3721 src = GST_MESSAGE_SRC (message);
3722 type = GST_MESSAGE_TYPE (message);
3724 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3725 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3726 GST_MESSAGE_TYPE_NAME (message));
3729 case GST_MESSAGE_ERROR:
3731 GST_OBJECT_LOCK (bin);
3733 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3734 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3735 GST_STATE_BROADCAST (bin);
3736 GST_OBJECT_UNLOCK (bin);
3740 case GST_MESSAGE_EOS:
3743 /* collect all eos messages from the children */
3744 bin_do_message_forward (bin, message);
3745 GST_OBJECT_LOCK (bin);
3746 /* ref message for future use */
3747 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3748 GST_OBJECT_UNLOCK (bin);
3753 case GST_MESSAGE_STREAM_START:
3756 /* collect all stream_start messages from the children */
3757 GST_OBJECT_LOCK (bin);
3758 /* ref message for future use */
3759 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3760 GST_OBJECT_UNLOCK (bin);
3762 bin_do_stream_start (bin);
3765 case GST_MESSAGE_STATE_DIRTY:
3767 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3770 gst_message_unref (message);
3773 case GST_MESSAGE_SEGMENT_START:{
3774 gboolean post = FALSE;
3778 gst_message_parse_segment_start (message, &format, &position);
3779 seqnum = gst_message_get_seqnum (message);
3781 bin_do_message_forward (bin, message);
3783 GST_OBJECT_LOCK (bin);
3784 /* if this is the first segment-start, post to parent but not to the
3786 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3787 (GST_OBJECT_PARENT (bin) != NULL)) {
3790 /* replace any previous segment_start message from this source
3791 * with the new segment start message */
3792 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3793 GST_OBJECT_UNLOCK (bin);
3795 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3797 gst_message_set_seqnum (tmessage, seqnum);
3799 /* post segment start with initial format and position. */
3800 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3802 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3806 case GST_MESSAGE_SEGMENT_DONE:
3808 gboolean post = FALSE;
3812 gst_message_parse_segment_done (message, &format, &position);
3813 seqnum = gst_message_get_seqnum (message);
3815 bin_do_message_forward (bin, message);
3817 GST_OBJECT_LOCK (bin);
3818 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3819 /* if there are no more segment_start messages, everybody posted
3820 * a segment_done and we can post one on the bus. */
3822 /* we don't care who still has a pending segment start */
3823 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3826 /* remove all old segment_done messages */
3827 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3829 GST_OBJECT_UNLOCK (bin);
3831 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3833 gst_message_set_seqnum (tmessage, seqnum);
3835 /* post segment done with latest format and position. */
3836 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3838 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3842 case GST_MESSAGE_CLOCK_LOST:
3844 GstClock **provided_clock_p;
3845 GstElement **clock_provider_p;
3846 gboolean playing, toplevel, provided, forward;
3849 gst_message_parse_clock_lost (message, &clock);
3851 GST_OBJECT_LOCK (bin);
3852 bin->clock_dirty = TRUE;
3853 /* if we lost the clock that we provided, post to parent but
3854 * only if we are not a top-level bin or PLAYING.
3855 * The reason for this is that applications should be able
3856 * to PAUSE/PLAY if they receive this message without worrying
3857 * about the state of the pipeline. */
3858 provided = (clock == bin->provided_clock);
3859 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3860 toplevel = GST_OBJECT_PARENT (bin) == NULL;
3861 forward = provided && (playing || !toplevel);
3863 GST_DEBUG_OBJECT (bin,
3864 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3865 bin->provided_clock, bin->clock_provider);
3866 provided_clock_p = &bin->provided_clock;
3867 clock_provider_p = &bin->clock_provider;
3868 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3869 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3871 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3872 provided, playing, forward);
3873 GST_OBJECT_UNLOCK (bin);
3879 gst_message_unref (message);
3882 case GST_MESSAGE_CLOCK_PROVIDE:
3886 GST_OBJECT_LOCK (bin);
3887 bin->clock_dirty = TRUE;
3888 /* a new clock is available, post to parent but not
3889 * to the application */
3890 forward = GST_OBJECT_PARENT (bin) != NULL;
3891 GST_OBJECT_UNLOCK (bin);
3897 gst_message_unref (message);
3900 case GST_MESSAGE_ASYNC_START:
3904 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3905 src ? GST_OBJECT_NAME (src) : "(NULL)");
3907 bin_do_message_forward (bin, message);
3909 GST_OBJECT_LOCK (bin);
3910 /* we ignore the message if we are going to <= READY */
3911 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3912 goto ignore_start_message;
3914 /* takes ownership of the message */
3915 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3917 bin_handle_async_start (bin);
3918 GST_OBJECT_UNLOCK (bin);
3921 ignore_start_message:
3923 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3924 gst_element_state_get_name (target));
3925 GST_OBJECT_UNLOCK (bin);
3926 gst_message_unref (message);
3930 case GST_MESSAGE_ASYNC_DONE:
3932 GstClockTime running_time;
3935 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3936 src ? GST_OBJECT_NAME (src) : "(NULL)");
3938 gst_message_parse_async_done (message, &running_time);
3940 bin_do_message_forward (bin, message);
3942 GST_OBJECT_LOCK (bin);
3943 /* ignore messages if we are shutting down */
3944 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3945 goto ignore_done_message;
3947 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3948 /* if there are no more ASYNC_START messages, everybody posted
3949 * a ASYNC_DONE and we can post one on the bus. When checking, we
3950 * don't care who still has a pending ASYNC_START */
3951 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3952 /* nothing found, remove all old ASYNC_DONE messages */
3953 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3955 GST_DEBUG_OBJECT (bin, "async elements committed");
3956 /* when we get an async done message when a state change was busy, we
3957 * need to set the pending_done flag so that at the end of the state
3958 * change we can see if we need to verify pending async elements, hence
3959 * the TRUE argument here. */
3960 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3963 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3965 GST_OBJECT_UNLOCK (bin);
3968 ignore_done_message:
3970 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3971 gst_element_state_get_name (target));
3972 GST_OBJECT_UNLOCK (bin);
3973 gst_message_unref (message);
3977 case GST_MESSAGE_STRUCTURE_CHANGE:
3981 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3983 GST_OBJECT_LOCK (bin);
3985 /* while the pad is busy, avoid following it when doing state changes.
3986 * Don't update the cookie yet, we will do that after the structure
3987 * change finished and we are ready to inspect the new updated
3989 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3992 /* a pad link/unlink ended, signal the state change iterator that we
3993 * need to resync by updating the structure_cookie. */
3994 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3995 GST_MESSAGE_STRUCTURE_CHANGE);
3996 if (!GST_BIN_IS_NO_RESYNC (bin))
3997 bin->priv->structure_cookie++;
3999 GST_OBJECT_UNLOCK (bin);
4002 gst_message_unref (message);
4006 case GST_MESSAGE_NEED_CONTEXT:{
4007 const gchar *context_type;
4008 GList *l, *contexts;
4010 gst_message_parse_context_type (message, &context_type);
4013 GST_OBJECT_LOCK (bin);
4014 contexts = GST_ELEMENT_CAST (bin)->contexts;
4015 GST_LOG_OBJECT (bin, "got need-context message type: %s", context_type);
4016 for (l = contexts; l; l = l->next) {
4017 GstContext *tmp = l->data;
4018 const gchar *tmp_type = gst_context_get_context_type (tmp);
4020 if (strcmp (context_type, tmp_type) == 0) {
4021 gst_element_set_context (GST_ELEMENT (src), l->data);
4025 GST_OBJECT_UNLOCK (bin);
4027 /* Forward if we couldn't answer the message */
4031 gst_message_unref (message);
4035 ("Got need-context message in bin '%s' without source element, dropping",
4036 GST_ELEMENT_NAME (bin));
4037 gst_message_unref (message);
4042 case GST_MESSAGE_HAVE_CONTEXT:{
4043 GstContext *context;
4045 gst_message_parse_have_context (message, &context);
4046 gst_bin_update_context (bin, context);
4047 gst_context_unref (context);
4059 /* Send all other messages upward */
4060 GST_DEBUG_OBJECT (bin, "posting message upward");
4061 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
4066 /* generic struct passed to all query fold methods */
4075 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
4076 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
4078 /* for duration/position we collect all durations/positions and take
4079 * the MAX of all valid results */
4081 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
4089 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4091 gboolean res = FALSE;
4092 GstObject *item = g_value_get_object (vitem);
4093 if (GST_IS_PAD (item))
4094 res = gst_pad_query (GST_PAD (item), fold->query);
4096 res = gst_element_query (GST_ELEMENT (item), fold->query);
4101 g_value_set_boolean (ret, TRUE);
4103 gst_query_parse_duration (fold->query, NULL, &duration);
4105 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
4107 if (duration == -1) {
4108 /* duration query succeeded, but duration is unknown */
4113 if (duration > fold->max)
4114 fold->max = duration;
4121 bin_query_duration_done (GstBin * bin, QueryFold * fold)
4125 gst_query_parse_duration (fold->query, &format, NULL);
4126 /* store max in query result */
4127 gst_query_set_duration (fold->query, format, fold->max);
4129 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
4133 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4135 gboolean res = FALSE;
4136 GstObject *item = g_value_get_object (vitem);
4137 if (GST_IS_PAD (item))
4138 res = gst_pad_query (GST_PAD (item), fold->query);
4140 res = gst_element_query (GST_ELEMENT (item), fold->query);
4145 g_value_set_boolean (ret, TRUE);
4147 gst_query_parse_position (fold->query, NULL, &position);
4149 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
4151 if (position > fold->max)
4152 fold->max = position;
4159 bin_query_position_done (GstBin * bin, QueryFold * fold)
4163 gst_query_parse_position (fold->query, &format, NULL);
4164 /* store max in query result */
4165 gst_query_set_position (fold->query, format, fold->max);
4167 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
4171 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4173 gboolean res = FALSE;
4174 GstObject *item = g_value_get_object (vitem);
4175 if (GST_IS_PAD (item))
4176 res = gst_pad_query (GST_PAD (item), fold->query);
4178 res = gst_element_query (GST_ELEMENT (item), fold->query);
4180 GstClockTime min, max;
4183 gst_query_parse_latency (fold->query, &live, &min, &max);
4185 GST_DEBUG_OBJECT (item,
4186 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
4187 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
4189 /* for the combined latency we collect the MAX of all min latencies and
4190 * the MIN of all max latencies */
4192 if (min > fold->min)
4194 if (fold->max == -1)
4196 else if (max < fold->max)
4202 g_value_set_boolean (ret, FALSE);
4203 GST_DEBUG_OBJECT (item, "failed query");
4210 bin_query_latency_done (GstBin * bin, QueryFold * fold)
4212 /* store max in query result */
4213 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
4215 GST_DEBUG_OBJECT (bin,
4216 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
4217 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
4221 /* generic fold, return first valid result */
4223 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4225 gboolean res = FALSE;
4226 GstObject *item = g_value_get_object (vitem);
4227 if (GST_IS_PAD (item))
4228 res = gst_pad_query (GST_PAD (item), fold->query);
4230 res = gst_element_query (GST_ELEMENT (item), fold->query);
4232 g_value_set_boolean (ret, TRUE);
4233 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
4236 /* and stop as soon as we have a valid result */
4240 /* Perform a query iteration for the given bin. The query is stored in
4241 * QueryFold and iter should be either a GstPad iterator or a
4242 * GstElement iterator. */
4244 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
4245 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
4246 QueryFold * fold_data, gboolean default_return)
4248 gboolean res = default_return;
4250 /* set the result of the query to FALSE initially */
4251 g_value_init (&ret, G_TYPE_BOOLEAN);
4252 g_value_set_boolean (&ret, res);
4255 GstIteratorResult ires;
4257 ires = gst_iterator_fold (iter, fold_func, &ret, fold_data);
4260 case GST_ITERATOR_RESYNC:
4261 gst_iterator_resync (iter);
4263 fold_init (bin, fold_data);
4264 g_value_set_boolean (&ret, res);
4266 case GST_ITERATOR_OK:
4267 case GST_ITERATOR_DONE:
4268 res = g_value_get_boolean (&ret);
4269 if (fold_done != NULL && res)
4270 fold_done (bin, fold_data);
4282 gst_bin_query (GstElement * element, GstQuery * query)
4284 GstBin *bin = GST_BIN_CAST (element);
4286 gboolean default_return = FALSE;
4287 gboolean res = FALSE;
4288 gboolean src_pads_query_result = FALSE;
4289 GstIteratorFoldFunction fold_func;
4290 QueryInitFunction fold_init = NULL;
4291 QueryDoneFunction fold_done = NULL;
4292 QueryFold fold_data;
4294 switch (GST_QUERY_TYPE (query)) {
4295 case GST_QUERY_DURATION:
4297 /* iterate and collect durations */
4298 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
4299 fold_init = bin_query_min_max_init;
4300 fold_done = bin_query_duration_done;
4303 case GST_QUERY_POSITION:
4305 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
4306 fold_init = bin_query_min_max_init;
4307 fold_done = bin_query_position_done;
4310 case GST_QUERY_LATENCY:
4312 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
4313 fold_init = bin_query_min_max_init;
4314 fold_done = bin_query_latency_done;
4315 default_return = TRUE;
4319 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
4323 fold_data.query = query;
4325 iter = gst_bin_iterate_sinks (bin);
4326 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
4327 query, GST_QUERY_TYPE_NAME (query));
4330 fold_init (bin, &fold_data);
4333 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, &fold_data,
4335 gst_iterator_free (iter);
4338 /* Query the source pads of the element */
4339 iter = gst_element_iterate_src_pads (element);
4340 src_pads_query_result =
4341 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
4342 &fold_data, default_return);
4343 gst_iterator_free (iter);
4345 if (src_pads_query_result)
4349 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
4355 set_context (const GValue * item, gpointer user_data)
4357 GstElement *element = g_value_get_object (item);
4359 gst_element_set_context (element, user_data);
4363 gst_bin_set_context (GstElement * element, GstContext * context)
4366 GstIterator *children;
4368 g_return_if_fail (GST_IS_BIN (element));
4370 bin = GST_BIN (element);
4372 GST_ELEMENT_CLASS (parent_class)->set_context (element, context);
4374 children = gst_bin_iterate_elements (bin);
4375 while (gst_iterator_foreach (children, set_context,
4376 context) == GST_ITERATOR_RESYNC)
4377 gst_iterator_resync (children);
4378 gst_iterator_free (children);
4382 compare_name (const GValue * velement, const gchar * name)
4385 GstElement *element = g_value_get_object (velement);
4387 GST_OBJECT_LOCK (element);
4388 eq = strcmp (GST_ELEMENT_NAME (element), name);
4389 GST_OBJECT_UNLOCK (element);
4395 * gst_bin_get_by_name:
4397 * @name: the element name to search for
4399 * Gets the element with the given name from a bin. This
4400 * function recurses into child bins.
4402 * Returns: (transfer full) (nullable): the #GstElement with the given
4406 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4408 GstIterator *children;
4409 GValue result = { 0, };
4410 GstElement *element;
4413 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4415 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4416 GST_ELEMENT_NAME (bin), name);
4418 children = gst_bin_iterate_recurse (bin);
4419 found = gst_iterator_find_custom (children,
4420 (GCompareFunc) compare_name, &result, (gpointer) name);
4421 gst_iterator_free (children);
4424 element = g_value_dup_object (&result);
4425 g_value_unset (&result);
4434 * gst_bin_get_by_name_recurse_up:
4436 * @name: the element name to search for
4438 * Gets the element with the given name from this bin. If the
4439 * element is not found, a recursion is performed on the parent bin.
4441 * Returns: (transfer full) (nullable): the #GstElement with the given
4445 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4449 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4450 g_return_val_if_fail (name != NULL, NULL);
4452 result = gst_bin_get_by_name (bin, name);
4457 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4459 if (GST_IS_BIN (parent)) {
4460 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4462 gst_object_unref (parent);
4470 compare_interface (const GValue * velement, GValue * interface)
4472 GstElement *element = g_value_get_object (velement);
4473 GType interface_type = (GType) g_value_get_pointer (interface);
4476 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4485 * gst_bin_get_by_interface:
4487 * @iface: the #GType of an interface
4489 * Looks for an element inside the bin that implements the given
4490 * interface. If such an element is found, it returns the element.
4491 * You can cast this element to the given interface afterwards. If you want
4492 * all elements that implement the interface, use
4493 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4495 * Returns: (transfer full) (nullable): A #GstElement inside the bin
4496 * implementing the interface
4499 gst_bin_get_by_interface (GstBin * bin, GType iface)
4501 GstIterator *children;
4502 GValue result = { 0, };
4503 GstElement *element;
4505 GValue viface = { 0, };
4507 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4508 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4510 g_value_init (&viface, G_TYPE_POINTER);
4511 g_value_set_pointer (&viface, (gpointer) iface);
4513 children = gst_bin_iterate_recurse (bin);
4514 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4516 gst_iterator_free (children);
4519 element = g_value_dup_object (&result);
4520 g_value_unset (&result);
4524 g_value_unset (&viface);
4530 * gst_bin_iterate_all_by_interface:
4532 * @iface: the #GType of an interface
4534 * Looks for all elements inside the bin that implements the given
4535 * interface. You can safely cast all returned elements to the given interface.
4536 * The function recurses inside child bins. The iterator will yield a series
4539 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
4540 * for all elements in the bin implementing the given interface
4543 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4545 GstIterator *children;
4546 GstIterator *result;
4547 GValue viface = { 0, };
4549 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4550 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4552 g_value_init (&viface, G_TYPE_POINTER);
4553 g_value_set_pointer (&viface, (gpointer) iface);
4555 children = gst_bin_iterate_recurse (bin);
4556 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4559 g_value_unset (&viface);
4565 compare_factory_names (const GValue * velement, GValue * factory_name_val)
4567 GstElement *element = g_value_get_object (velement);
4568 GstElementFactory *factory = gst_element_get_factory (element);
4569 const gchar *factory_name = g_value_get_string (factory_name_val);
4571 if (factory == NULL)
4574 return g_strcmp0 (GST_OBJECT_NAME (factory), factory_name);
4578 * gst_bin_iterate_all_by_element_factory_name:
4580 * @factory_name: (not nullable): the name of the #GstElementFactory
4582 * Looks for all elements inside the bin with the given element factory name.
4583 * The function recurses inside child bins. The iterator will yield a series of
4586 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
4587 * for all elements in the bin with the given element factory name
4592 gst_bin_iterate_all_by_element_factory_name (GstBin * bin,
4593 const gchar * factory_name)
4595 GstIterator *children;
4596 GstIterator *result;
4597 GValue factory_name_val = G_VALUE_INIT;
4599 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4600 g_return_val_if_fail (factory_name && *factory_name, NULL);
4602 g_value_init (&factory_name_val, G_TYPE_STRING);
4603 g_value_set_string (&factory_name_val, factory_name);
4605 children = gst_bin_iterate_recurse (bin);
4606 result = gst_iterator_filter (children, (GCompareFunc) compare_factory_names,
4609 g_value_unset (&factory_name_val);