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.
29 * @short_description: Base class and element that can contain other elements
31 * #GstBin is an element that can contain other #GstElement, allowing them to be
33 * Pads from the child elements can be ghosted to the bin, see #GstGhostPad.
34 * This makes the bin look like any other elements and enables creation of
35 * higher-level abstraction elements.
37 * A new #GstBin is created with gst_bin_new(). Use a #GstPipeline instead if you
38 * want to create a toplevel bin because a normal bin doesn't have a bus or
39 * handle clock distribution of its own.
41 * After the bin has been created you will typically add elements to it with
42 * gst_bin_add(). You can remove elements with gst_bin_remove().
44 * An element can be retrieved from a bin with gst_bin_get_by_name(), using the
45 * elements name. gst_bin_get_by_name_recurse_up() is mainly used for internal
46 * purposes and will query the parent bins when the element is not found in the
49 * An iterator of elements in a bin can be retrieved with
50 * gst_bin_iterate_elements(). Various other iterators exist to retrieve the
53 * gst_object_unref() is used to drop your reference to the bin.
55 * The #GstBin::element-added signal is fired whenever a new element is added to
56 * the bin. Likewise the #GstBin::element-removed signal is fired whenever an
57 * element is removed from the bin.
61 * A #GstBin internally intercepts every #GstMessage posted by its children and
62 * implements the following default behaviour for each of them:
64 * * GST_MESSAGE_EOS: This message is only posted by sinks in the PLAYING
65 * state. If all sinks posted the EOS message, this bin will post and EOS
68 * * GST_MESSAGE_SEGMENT_START: Just collected and never forwarded upwards.
69 * The messages are used to decide when all elements have completed playback
72 * * GST_MESSAGE_SEGMENT_DONE: Is posted by #GstBin when all elements that posted
73 * a SEGMENT_START have posted a SEGMENT_DONE.
75 * * GST_MESSAGE_DURATION_CHANGED: Is posted by an element that detected a change
76 * in the stream duration. The default bin behaviour is to clear any
77 * cached duration values so that the next duration query will perform
78 * a full duration recalculation. The duration change is posted to the
79 * application so that it can refetch the new duration with a duration
80 * query. Note that these messages can be posted before the bin is
81 * prerolled, in which case the duration query might fail.
83 * * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
84 * can no longer provide a clock. The default bin behaviour is to
85 * check if the lost clock was the one provided by the bin. If so and
86 * the bin is currently in the PLAYING state, the message is forwarded to
88 * This message is also generated when a clock provider is removed from
89 * the bin. If this message is received by the application, it should
90 * PAUSE the pipeline and set it back to PLAYING to force a new clock
93 * * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
94 * can provide a clock. This mostly happens when a new clock
95 * provider is added to the bin. The default behaviour of the bin is to
96 * mark the currently selected clock as dirty, which will perform a clock
97 * recalculation the next time the bin is asked to provide a clock.
98 * This message is never sent tot the application but is forwarded to
99 * the parent of the bin.
101 * * OTHERS: posted upwards.
103 * A #GstBin implements the following default behaviour for answering to a
106 * * GST_QUERY_DURATION:If the query has been asked before with the same format
107 * and the bin is a toplevel bin (ie. has no parent),
108 * use the cached previous value. If no previous value was cached, the
109 * query is sent to all sink elements in the bin and the MAXIMUM of all
110 * values is returned. If the bin is a toplevel bin the value is cached.
111 * If no sinks are available in the bin, the query fails.
113 * * GST_QUERY_POSITION:The query is sent to all sink elements in the bin and the
114 * MAXIMUM of all values is returned. If no sinks are available in the bin,
117 * * OTHERS:the query is forwarded to all sink elements, the result
118 * of the first sink that answers the query successfully is returned. If no
119 * sink is in the bin, the query fails.
121 * A #GstBin will by default forward any event sent to it to all sink
122 * (#GST_EVENT_TYPE_DOWNSTREAM) or source (#GST_EVENT_TYPE_UPSTREAM) elements
123 * depending on the event type.
124 * If all the elements return %TRUE, the bin will also return %TRUE, else %FALSE
125 * is returned. If no elements of the required type are in the bin, the event
126 * handler will return %TRUE.
130 #include "gst_private.h"
132 #include "gstevent.h"
135 #include "gsterror.h"
137 #include "gstutils.h"
138 #include "gstchildproxy.h"
140 GST_DEBUG_CATEGORY_STATIC (bin_debug);
141 #define GST_CAT_DEFAULT bin_debug
143 /* a bin is toplevel if it has no parent or when it is configured to behave like
145 #define BIN_IS_TOPLEVEL(bin) ((GST_OBJECT_PARENT (bin) == NULL) || bin->priv->asynchandling)
147 #define GST_BIN_GET_PRIVATE(obj) \
148 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BIN, GstBinPrivate))
150 struct _GstBinPrivate
152 gboolean asynchandling;
153 /* if we get an ASYNC_DONE message from ourselves, this means that the
154 * subclass will simulate ASYNC behaviour without having ASYNC children. When
155 * such an ASYNC_DONE message is posted while we are doing a state change, we
156 * have to process the message after finishing the state change even when no
157 * child returned GST_STATE_CHANGE_ASYNC. */
158 gboolean pending_async_done;
160 guint32 structure_cookie;
167 /* forward messages from our children */
168 gboolean message_forward;
171 gboolean posted_playing;
172 GstElementFlags suppressed_flags;
181 static void gst_bin_dispose (GObject * object);
183 static void gst_bin_set_property (GObject * object, guint prop_id,
184 const GValue * value, GParamSpec * pspec);
185 static void gst_bin_get_property (GObject * object, guint prop_id,
186 GValue * value, GParamSpec * pspec);
188 static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
189 GstStateChange transition);
190 static gboolean gst_bin_post_message (GstElement * element, GstMessage * msg);
191 static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
192 GstState * state, GstState * pending, GstClockTime timeout);
193 static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
194 gboolean flag_pending, GstClockTime running_time);
195 static void bin_handle_async_start (GstBin * bin);
196 static void bin_push_state_continue (GstBin * bin, BinContinueData * data);
197 static void bin_do_eos (GstBin * bin);
199 static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
200 static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
201 static void gst_bin_deep_element_added_func (GstBin * bin, GstBin * sub_bin,
202 GstElement * element);
203 static void gst_bin_deep_element_removed_func (GstBin * bin, GstBin * sub_bin,
204 GstElement * element);
205 static void gst_bin_update_context (GstBin * bin, GstContext * context);
206 static void gst_bin_update_context_unlocked (GstBin * bin,
207 GstContext * context);
210 static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
211 static GstIndex *gst_bin_get_index_func (GstElement * element);
214 static GstClock *gst_bin_provide_clock_func (GstElement * element);
215 static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
217 static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
218 static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
219 static GstBusSyncReply bin_bus_handler (GstBus * bus,
220 GstMessage * message, GstBin * bin);
221 static gboolean gst_bin_query (GstElement * element, GstQuery * query);
222 static void gst_bin_set_context (GstElement * element, GstContext * context);
224 static gboolean gst_bin_do_latency_func (GstBin * bin);
226 static void bin_remove_messages (GstBin * bin, GstObject * src,
227 GstMessageType types);
228 static void gst_bin_continue_func (GstBin * bin, BinContinueData * data);
229 static gint bin_element_is_sink (GstElement * child, GstBin * bin);
230 static gint bin_element_is_src (GstElement * child, GstBin * bin);
232 static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
234 /* Bin signals and properties */
241 DEEP_ELEMENT_REMOVED,
245 #define DEFAULT_ASYNC_HANDLING FALSE
246 #define DEFAULT_MESSAGE_FORWARD FALSE
252 PROP_MESSAGE_FORWARD,
256 static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
258 static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
262 static const GInterfaceInfo iface_info = { \
263 gst_bin_child_proxy_init, \
267 g_type_add_interface_static (g_define_type_id, GST_TYPE_CHILD_PROXY, &iface_info); \
269 GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
270 "debugging info for the 'bin' container element"); \
274 #define gst_bin_parent_class parent_class
275 G_DEFINE_TYPE_WITH_CODE (GstBin, gst_bin, GST_TYPE_ELEMENT, _do_init);
278 gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
284 bin = GST_BIN_CAST (child_proxy);
286 GST_OBJECT_LOCK (bin);
287 if ((res = g_list_nth_data (bin->children, index)))
288 gst_object_ref (res);
289 GST_OBJECT_UNLOCK (bin);
291 return (GObject *) res;
295 gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
300 bin = GST_BIN_CAST (child_proxy);
302 GST_OBJECT_LOCK (bin);
303 num = bin->numchildren;
304 GST_OBJECT_UNLOCK (bin);
310 gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
312 GstChildProxyInterface *iface = g_iface;
314 iface->get_children_count = gst_bin_child_proxy_get_children_count;
315 iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
319 _gst_boolean_accumulator (GSignalInvocationHint * ihint,
320 GValue * return_accu, const GValue * handler_return, gpointer dummy)
324 myboolean = g_value_get_boolean (handler_return);
325 if (!(ihint->run_type & G_SIGNAL_RUN_CLEANUP))
326 g_value_set_boolean (return_accu, myboolean);
328 GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
335 gst_bin_class_init (GstBinClass * klass)
337 GObjectClass *gobject_class;
338 GstElementClass *gstelement_class;
340 gobject_class = (GObjectClass *) klass;
341 gstelement_class = (GstElementClass *) klass;
343 g_type_class_add_private (klass, sizeof (GstBinPrivate));
345 gobject_class->set_property = gst_bin_set_property;
346 gobject_class->get_property = gst_bin_get_property;
349 * GstBin:async-handling:
351 * If set to %TRUE, the bin will handle asynchronous state changes.
352 * This should be used only if the bin subclass is modifying the state
353 * of its children on its own.
355 g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
356 g_param_spec_boolean ("async-handling", "Async Handling",
357 "The bin will handle Asynchronous state changes",
358 DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
361 * GstBin::element-added:
363 * @element: the #GstElement that was added to the bin
365 * Will be emitted after the element was added to the bin.
367 gst_bin_signals[ELEMENT_ADDED] =
368 g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
369 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
370 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
372 * GstBin::element-removed:
374 * @element: the #GstElement that was removed from the bin
376 * Will be emitted after the element was removed from the bin.
378 gst_bin_signals[ELEMENT_REMOVED] =
379 g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
380 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
381 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
383 * GstBin::deep-element-added:
385 * @sub_bin: the #GstBin the element was added to
386 * @element: the #GstElement that was added to @sub_bin
388 * Will be emitted after the element was added to sub_bin.
392 gst_bin_signals[DEEP_ELEMENT_ADDED] =
393 g_signal_new ("deep-element-added", G_TYPE_FROM_CLASS (klass),
394 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, deep_element_added),
395 NULL, NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 2, GST_TYPE_BIN,
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, g_cclosure_marshal_generic, G_TYPE_NONE, 2, GST_TYPE_BIN,
413 * GstBin::do-latency:
416 * Will be emitted when the bin needs to perform latency calculations. This
417 * signal is only emitted for toplevel bins or when async-handling is
420 * Only one signal handler is invoked. If no signals are connected, the
421 * default handler is invoked, which will query and distribute the lowest
422 * possible latency to all sinks.
424 * Connect to this signal if the default latency calculations are not
425 * sufficient, like when you need different latencies for different sinks in
428 gst_bin_signals[DO_LATENCY] =
429 g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
430 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
431 _gst_boolean_accumulator, NULL, g_cclosure_marshal_generic,
432 G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
435 * GstBin:message-forward:
437 * Forward all children messages, even those that would normally be filtered by
438 * the bin. This can be interesting when one wants to be notified of the EOS
439 * state of individual elements, for example.
441 * The messages are converted to an ELEMENT message with the bin as the
442 * source. The structure of the message is named 'GstBinForwarded' and contains
443 * a field named 'message' of type GST_TYPE_MESSAGE that contains the original
446 g_object_class_install_property (gobject_class, PROP_MESSAGE_FORWARD,
447 g_param_spec_boolean ("message-forward", "Message Forward",
448 "Forwards all children messages",
449 DEFAULT_MESSAGE_FORWARD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
451 gobject_class->dispose = gst_bin_dispose;
453 gst_element_class_set_static_metadata (gstelement_class, "Generic bin",
455 "Simple container object",
456 "Erik Walthinsen <omega@cse.ogi.edu>,"
457 "Wim Taymans <wim.taymans@gmail.com>");
459 gstelement_class->change_state =
460 GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
461 gstelement_class->post_message = GST_DEBUG_FUNCPTR (gst_bin_post_message);
462 gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
464 gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
465 gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
467 gstelement_class->provide_clock =
468 GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
469 gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
471 gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
472 gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
473 gstelement_class->set_context = GST_DEBUG_FUNCPTR (gst_bin_set_context);
475 klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
476 klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
477 klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
479 klass->deep_element_added = gst_bin_deep_element_added_func;
480 klass->deep_element_removed = gst_bin_deep_element_removed_func;
482 klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
486 gst_bin_init (GstBin * bin)
490 bin->numchildren = 0;
491 bin->children = NULL;
492 bin->children_cookie = 0;
493 bin->messages = NULL;
494 bin->provided_clock = NULL;
495 bin->clock_dirty = FALSE;
497 /* Set up a bus for listening to child elements */
498 bus = g_object_new (GST_TYPE_BUS, "enable-async", FALSE, NULL);
499 bin->child_bus = bus;
500 GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
502 gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin,
505 bin->priv = GST_BIN_GET_PRIVATE (bin);
506 bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
507 bin->priv->structure_cookie = 0;
508 bin->priv->message_forward = DEFAULT_MESSAGE_FORWARD;
512 gst_bin_dispose (GObject * object)
514 GstBin *bin = GST_BIN_CAST (object);
515 GstBus **child_bus_p = &bin->child_bus;
516 GstClock **provided_clock_p = &bin->provided_clock;
517 GstElement **clock_provider_p = &bin->clock_provider;
519 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "%p dispose", object);
521 GST_OBJECT_LOCK (object);
522 gst_object_replace ((GstObject **) child_bus_p, NULL);
523 gst_object_replace ((GstObject **) provided_clock_p, NULL);
524 gst_object_replace ((GstObject **) clock_provider_p, NULL);
525 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
526 GST_OBJECT_UNLOCK (object);
528 while (bin->children) {
529 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
531 if (G_UNLIKELY (bin->children != NULL)) {
532 g_critical ("could not remove elements from bin '%s'",
533 GST_STR_NULL (GST_OBJECT_NAME (object)));
536 G_OBJECT_CLASS (parent_class)->dispose (object);
541 * @name: (allow-none): the name of the new bin
543 * Creates a new bin with the given name.
545 * Returns: (transfer floating): a new #GstBin
548 gst_bin_new (const gchar * name)
550 return gst_element_factory_make ("bin", name);
554 gst_bin_set_property (GObject * object, guint prop_id,
555 const GValue * value, GParamSpec * pspec)
559 gstbin = GST_BIN_CAST (object);
562 case PROP_ASYNC_HANDLING:
563 GST_OBJECT_LOCK (gstbin);
564 gstbin->priv->asynchandling = g_value_get_boolean (value);
565 GST_OBJECT_UNLOCK (gstbin);
567 case PROP_MESSAGE_FORWARD:
568 GST_OBJECT_LOCK (gstbin);
569 gstbin->priv->message_forward = g_value_get_boolean (value);
570 GST_OBJECT_UNLOCK (gstbin);
573 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
579 gst_bin_get_property (GObject * object, guint prop_id,
580 GValue * value, GParamSpec * pspec)
584 gstbin = GST_BIN_CAST (object);
587 case PROP_ASYNC_HANDLING:
588 GST_OBJECT_LOCK (gstbin);
589 g_value_set_boolean (value, gstbin->priv->asynchandling);
590 GST_OBJECT_UNLOCK (gstbin);
592 case PROP_MESSAGE_FORWARD:
593 GST_OBJECT_LOCK (gstbin);
594 g_value_set_boolean (value, gstbin->priv->message_forward);
595 GST_OBJECT_UNLOCK (gstbin);
598 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
604 /* return the cached index */
606 gst_bin_get_index_func (GstElement * element)
611 bin = GST_BIN_CAST (element);
613 GST_OBJECT_LOCK (bin);
614 if ((result = bin->priv->index))
615 gst_object_ref (result);
616 GST_OBJECT_UNLOCK (bin);
621 /* set the index on all elements in this bin
626 gst_bin_set_index_func (GstElement * element, GstIndex * index)
632 GValue data = { 0, };
634 bin = GST_BIN_CAST (element);
636 GST_OBJECT_LOCK (bin);
637 old = bin->priv->index;
638 if (G_UNLIKELY (old == index))
641 gst_object_ref (index);
642 bin->priv->index = index;
643 GST_OBJECT_UNLOCK (bin);
646 gst_object_unref (old);
648 it = gst_bin_iterate_elements (bin);
650 /* set the index on all elements in the bin */
653 switch (gst_iterator_next (it, &data)) {
654 case GST_ITERATOR_OK:
656 GstElement *child = g_value_get_object (&data);
658 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
659 GST_ELEMENT_NAME (child));
660 gst_element_set_index (child, index);
662 g_value_reset (&data);
665 case GST_ITERATOR_RESYNC:
666 GST_DEBUG_OBJECT (bin, "iterator doing resync");
667 gst_iterator_resync (it);
670 case GST_ITERATOR_DONE:
671 GST_DEBUG_OBJECT (bin, "iterator done");
676 g_value_unset (&data);
677 gst_iterator_free (it);
682 GST_DEBUG_OBJECT (bin, "index was already set");
683 GST_OBJECT_UNLOCK (bin);
689 /* set the clock on all elements in this bin
694 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
700 GValue data = { 0, };
702 bin = GST_BIN_CAST (element);
704 it = gst_bin_iterate_elements (bin);
708 switch (gst_iterator_next (it, &data)) {
709 case GST_ITERATOR_OK:
711 GstElement *child = g_value_get_object (&data);
713 res &= gst_element_set_clock (child, clock);
715 g_value_reset (&data);
718 case GST_ITERATOR_RESYNC:
719 GST_DEBUG_OBJECT (bin, "iterator doing resync");
720 gst_iterator_resync (it);
724 case GST_ITERATOR_DONE:
725 GST_DEBUG_OBJECT (bin, "iterator done");
730 g_value_unset (&data);
731 gst_iterator_free (it);
734 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
739 /* get the clock for this bin by asking all of the children in this bin
741 * The ref of the returned clock in increased so unref after usage.
743 * We loop the elements in state order and pick the last clock we can
744 * get. This makes sure we get a clock from the source.
749 gst_bin_provide_clock_func (GstElement * element)
751 GstClock *result = NULL;
752 GstElement *provider = NULL;
757 GstClock **provided_clock_p;
758 GstElement **clock_provider_p;
760 bin = GST_BIN_CAST (element);
762 GST_OBJECT_LOCK (bin);
763 if (!bin->clock_dirty)
766 GST_DEBUG_OBJECT (bin, "finding new clock");
768 it = gst_bin_sort_iterator_new (bin);
769 GST_OBJECT_UNLOCK (bin);
773 switch (gst_iterator_next (it, &val)) {
774 case GST_ITERATOR_OK:
776 GstElement *child = g_value_get_object (&val);
779 clock = gst_element_provide_clock (child);
781 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
782 clock, GST_ELEMENT_NAME (child));
784 gst_object_unref (result);
785 gst_object_unref (provider);
788 provider = gst_object_ref (child);
791 g_value_reset (&val);
794 case GST_ITERATOR_RESYNC:
795 gst_iterator_resync (it);
798 case GST_ITERATOR_DONE:
803 g_value_unset (&val);
804 gst_iterator_free (it);
806 GST_OBJECT_LOCK (bin);
807 if (!bin->clock_dirty) {
809 gst_object_unref (provider);
811 gst_object_unref (result);
817 provided_clock_p = &bin->provided_clock;
818 clock_provider_p = &bin->clock_provider;
819 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
820 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
821 bin->clock_dirty = FALSE;
822 GST_DEBUG_OBJECT (bin,
823 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
825 /* Provider is not being returned to caller, just the result */
827 gst_object_unref (provider);
828 GST_OBJECT_UNLOCK (bin);
834 if ((result = bin->provided_clock))
835 gst_object_ref (result);
836 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
837 GST_OBJECT_UNLOCK (bin);
844 * functions for manipulating cached messages
849 GstMessageType types;
852 /* check if a message is of given src and type */
854 message_check (GstMessage * message, MessageFind * target)
859 eq &= GST_MESSAGE_SRC (message) == target->src;
861 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
862 GST_LOG ("looking at message %p: %d", message, eq);
868 find_message (GstBin * bin, GstObject * src, GstMessageType types)
876 result = g_list_find_custom (bin->messages, &find,
877 (GCompareFunc) message_check);
880 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
881 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
884 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
885 #ifndef GST_DISABLE_GST_DEBUG
889 for (i = 0; i < 32; i++)
890 if (types & (1U << i))
891 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1U << i));
899 /* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
902 * A message that is cached and has the same SRC and type is replaced
903 * by the given message.
906 bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
912 if ((src = GST_MESSAGE_SRC (message))) {
913 /* first find the previous message posted by this element */
914 if ((previous = find_message (bin, src, types))) {
915 GstMessage *previous_msg;
917 /* if we found a previous message, replace it */
918 previous_msg = previous->data;
919 previous->data = message;
921 GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
922 GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
923 GST_MESSAGE_TYPE_NAME (message));
925 gst_message_unref (previous_msg);
927 /* keep new message */
928 bin->messages = g_list_prepend (bin->messages, message);
930 GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
931 message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
934 GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
935 GST_MESSAGE_TYPE_NAME (message));
937 gst_message_unref (message);
942 /* with LOCK. Remove all messages of given types */
944 bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
952 for (walk = bin->messages; walk; walk = next) {
953 GstMessage *message = (GstMessage *) walk->data;
955 next = g_list_next (walk);
957 if (message_check (message, &find) == 0) {
958 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
959 "deleting message %p of type %s (types 0x%08x)", message,
960 GST_MESSAGE_TYPE_NAME (message), types);
961 bin->messages = g_list_delete_link (bin->messages, walk);
962 gst_message_unref (message);
964 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
965 "not deleting message %p of type 0x%08x", message,
966 GST_MESSAGE_TYPE (message));
972 /* Check if the bin is EOS. We do this by scanning all sinks and
973 * checking if they posted an EOS message.
975 * call with bin LOCK */
977 is_eos (GstBin * bin, guint32 * seqnum)
984 for (walk = bin->children; walk; walk = g_list_next (walk)) {
987 element = GST_ELEMENT_CAST (walk->data);
988 if (bin_element_is_sink (element, bin) == 0) {
989 /* check if element posted EOS */
991 find_message (bin, GST_OBJECT_CAST (element), GST_MESSAGE_EOS))) {
992 GST_DEBUG ("sink '%s' posted EOS", GST_ELEMENT_NAME (element));
993 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
996 GST_DEBUG ("sink '%s' did not post EOS yet",
997 GST_ELEMENT_NAME (element));
1003 /* FIXME: Some tests (e.g. elements/capsfilter) use
1004 * pipelines with a dangling sinkpad but no sink element.
1005 * These tests assume that no EOS message is ever
1006 * posted on the bus so let's keep that behaviour.
1007 * In valid pipelines this doesn't make a difference.
1009 return result && n_eos > 0;
1013 /* Check if the bin is STREAM_START. We do this by scanning all sinks and
1014 * checking if they posted an STREAM_START message.
1016 * call with bin LOCK */
1018 is_stream_start (GstBin * bin, guint32 * seqnum, gboolean * have_group_id,
1024 gboolean first = TRUE, same_group_id = TRUE;
1026 *have_group_id = TRUE;
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 GST_DEBUG ("sink '%s' posted STREAM_START", GST_ELEMENT_NAME (element));
1039 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1040 if (gst_message_parse_group_id (GST_MESSAGE_CAST (msgs->data),
1044 *group_id = tmp_group_id;
1046 if (tmp_group_id != *group_id)
1047 same_group_id = FALSE;
1050 *have_group_id = FALSE;
1053 GST_DEBUG ("sink '%s' did not post STREAM_START yet",
1054 GST_ELEMENT_NAME (element));
1061 /* If all have a group_id we only consider this stream started
1062 * if all group ids were the same and all sinks posted a stream-start
1065 return same_group_id && result;
1066 /* otherwise consider this stream started after all sinks
1067 * have reported stream-start for backward compatibility.
1068 * FIXME 2.0: This should go away! */
1073 unlink_pads (const GValue * item, gpointer user_data)
1078 pad = g_value_get_object (item);
1080 if ((peer = gst_pad_get_peer (pad))) {
1081 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
1082 gst_pad_unlink (pad, peer);
1084 gst_pad_unlink (peer, pad);
1085 gst_object_unref (peer);
1090 bin_deep_iterator_foreach (const GValue * item, gpointer user_data)
1092 GQueue *queue = user_data;
1094 g_queue_push_tail (queue, g_value_dup_object (item));
1098 gst_bin_do_deep_add_remove (GstBin * bin, gint sig_id, const gchar * sig_name,
1099 GstElement * element)
1101 g_signal_emit (bin, sig_id, 0, bin, element);
1103 /* When removing a bin, emit deep-element-* for everything in the bin too */
1104 if (GST_IS_BIN (element)) {
1106 GstIteratorResult ires;
1107 GQueue elements = G_QUEUE_INIT;
1109 GST_LOG_OBJECT (bin, "Recursing into bin %" GST_PTR_FORMAT " for %s",
1111 it = gst_bin_iterate_recurse (GST_BIN_CAST (element));
1113 ires = gst_iterator_foreach (it, bin_deep_iterator_foreach, &elements);
1114 if (ires != GST_ITERATOR_DONE) {
1115 g_queue_foreach (&elements, (GFunc) g_object_unref, NULL);
1116 g_queue_clear (&elements);
1118 if (ires == GST_ITERATOR_RESYNC)
1119 gst_iterator_resync (it);
1120 } while (ires == GST_ITERATOR_RESYNC);
1121 if (ires != GST_ITERATOR_ERROR) {
1124 while ((e = g_queue_pop_head (&elements))) {
1125 GstObject *parent = gst_object_get_parent (GST_OBJECT_CAST (e));
1127 GST_LOG_OBJECT (bin, "calling %s for element %" GST_PTR_FORMAT
1128 " in bin %" GST_PTR_FORMAT, sig_name, e, parent);
1129 g_signal_emit (bin, sig_id, 0, parent, e);
1130 gst_object_unref (parent);
1134 gst_iterator_free (it);
1138 /* vmethod that adds an element to a bin
1143 gst_bin_add_func (GstBin * bin, GstElement * element)
1147 gboolean is_sink, is_source, provides_clock, requires_clock;
1148 GstMessage *clock_message = NULL, *async_message = NULL;
1149 GstStateChangeReturn ret;
1150 GList *l, *elem_contexts, *need_context_messages;
1152 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1154 /* we obviously can't add ourself to ourself */
1155 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1158 /* get the element name to make sure it is unique in this bin. */
1159 GST_OBJECT_LOCK (element);
1160 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1161 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1162 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1164 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1166 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1167 GST_OBJECT_UNLOCK (element);
1169 GST_OBJECT_LOCK (bin);
1171 /* then check to see if the element's name is already taken in the bin,
1172 * we can safely take the lock here. This check is probably bogus because
1173 * you can safely change the element name after this check and before setting
1174 * the object parent. The window is very small though... */
1175 if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
1176 goto duplicate_name;
1178 /* set the element's parent and add the element to the bin's list of children */
1179 if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
1180 GST_OBJECT_CAST (bin))))
1183 /* if we add a sink we become a sink */
1184 if (is_sink && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SINK)) {
1185 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
1187 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SINK);
1189 if (is_source && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SOURCE)) {
1190 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was source",
1192 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SOURCE);
1195 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_PROVIDE_CLOCK)) {
1196 GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
1198 gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
1199 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1202 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_REQUIRE_CLOCK)) {
1203 GST_DEBUG_OBJECT (bin, "element \"%s\" requires a clock", elem_name);
1204 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1207 bin->children = g_list_prepend (bin->children, element);
1209 bin->children_cookie++;
1210 if (!GST_BIN_IS_NO_RESYNC (bin))
1211 bin->priv->structure_cookie++;
1213 /* distribute the bus */
1214 gst_element_set_bus (element, bin->child_bus);
1216 /* propagate the current base_time, start_time and clock */
1217 gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
1218 gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
1219 /* it's possible that the element did not accept the clock but
1220 * that is not important right now. When the pipeline goes to PLAYING,
1221 * a new clock will be selected */
1222 gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
1224 /* get the element's list of contexts before propagating our own */
1225 elem_contexts = gst_element_get_contexts (element);
1226 for (l = GST_ELEMENT_CAST (bin)->contexts; l; l = l->next)
1227 gst_element_set_context (element, l->data);
1229 need_context_messages = NULL;
1230 for (l = elem_contexts; l; l = l->next) {
1231 GstContext *replacement, *context = l->data;
1232 const gchar *context_type;
1234 context_type = gst_context_get_context_type (context);
1236 /* we already set this context above? */
1238 gst_element_get_context_unlocked (GST_ELEMENT (bin), context_type);
1240 gst_context_unref (replacement);
1245 /* ask our parent for the context */
1246 msg = gst_message_new_need_context (GST_OBJECT_CAST (bin), context_type);
1247 s = (GstStructure *) gst_message_get_structure (msg);
1248 gst_structure_set (s, "bin.old.context", GST_TYPE_CONTEXT, context, NULL);
1250 need_context_messages = g_list_prepend (need_context_messages, msg);
1255 /* set the cached index on the children */
1256 if (bin->priv->index)
1257 gst_element_set_index (element, bin->priv->index);
1260 ret = GST_STATE_RETURN (bin);
1261 /* no need to update the state if we are in error */
1262 if (ret == GST_STATE_CHANGE_FAILURE)
1263 goto no_state_recalc;
1265 /* update the bin state, the new element could have been an ASYNC or
1266 * NO_PREROLL element */
1267 ret = GST_STATE_RETURN (element);
1268 GST_DEBUG_OBJECT (bin, "added %s element",
1269 gst_element_state_change_return_get_name (ret));
1272 case GST_STATE_CHANGE_ASYNC:
1274 /* create message to track this aync element when it posts an async-done
1276 async_message = gst_message_new_async_start (GST_OBJECT_CAST (element));
1279 case GST_STATE_CHANGE_NO_PREROLL:
1280 /* ignore all async elements we might have and commit our state */
1281 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1283 case GST_STATE_CHANGE_FAILURE:
1290 GST_OBJECT_UNLOCK (bin);
1292 for (l = need_context_messages; l; l = l->next) {
1293 GstMessage *msg = l->data;
1295 const gchar *context_type;
1296 GstContext *replacement, *context;
1298 gst_message_parse_context_type (msg, &context_type);
1300 GST_LOG_OBJECT (bin, "asking parent for context type: %s "
1301 "from %" GST_PTR_FORMAT, context_type, element);
1303 s = (GstStructure *) gst_message_get_structure (msg);
1304 gst_structure_get (s, "bin.old.context", GST_TYPE_CONTEXT, &context, NULL);
1305 gst_structure_remove_field (s, "bin.old.context");
1306 gst_element_post_message (GST_ELEMENT_CAST (bin), msg);
1308 /* lock to avoid losing a potential write */
1309 GST_OBJECT_LOCK (bin);
1311 gst_element_get_context_unlocked (GST_ELEMENT_CAST (bin), context_type);
1314 /* we got the context set from GstElement::set_context */
1315 gst_context_unref (replacement);
1316 GST_OBJECT_UNLOCK (bin);
1318 /* Propagate the element's context upwards */
1319 GST_LOG_OBJECT (bin, "propagating existing context type: %s %p "
1320 "from %" GST_PTR_FORMAT, context_type, context, element);
1322 gst_bin_update_context_unlocked (bin, context);
1325 gst_message_new_have_context (GST_OBJECT_CAST (bin),
1326 gst_context_ref (context));
1327 GST_OBJECT_UNLOCK (bin);
1328 gst_element_post_message (GST_ELEMENT_CAST (bin), msg);
1330 gst_context_unref (context);
1332 g_list_free_full (elem_contexts, (GDestroyNotify) gst_context_unref);
1333 g_list_free (need_context_messages);
1335 /* post the messages on the bus of the element so that the bin can handle
1338 gst_element_post_message (element, clock_message);
1341 gst_element_post_message (element, async_message);
1343 /* unlink all linked pads */
1344 it = gst_element_iterate_pads (element);
1345 while (gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads,
1346 NULL) == GST_ITERATOR_RESYNC)
1347 gst_iterator_resync (it);
1348 gst_iterator_free (it);
1350 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
1353 g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
1354 gst_child_proxy_child_added ((GstChildProxy *) bin, (GObject *) element,
1357 gst_bin_do_deep_add_remove (bin, gst_bin_signals[DEEP_ELEMENT_ADDED],
1358 "deep-element-added", element);
1364 /* ERROR handling here */
1367 GST_OBJECT_LOCK (bin);
1368 g_warning ("Cannot add bin '%s' to itself", GST_ELEMENT_NAME (bin));
1369 GST_OBJECT_UNLOCK (bin);
1370 gst_object_ref_sink (element);
1371 gst_object_unref (element);
1376 g_warning ("Name '%s' is not unique in bin '%s', not adding",
1377 elem_name, GST_ELEMENT_NAME (bin));
1378 GST_OBJECT_UNLOCK (bin);
1380 gst_object_ref_sink (element);
1381 gst_object_unref (element);
1386 g_warning ("Element '%s' already has parent", elem_name);
1387 GST_OBJECT_UNLOCK (bin);
1394 * gst_bin_set_suppressed_flags:
1396 * @flags: the #GstElementFlags to suppress
1398 * Suppress the given flags on the bin. #GstElementFlags of a
1399 * child element are propagated when it is added to the bin.
1400 * When suppressed flags are set, those specified flags will
1401 * not be propagated to the bin.
1408 gst_bin_set_suppressed_flags (GstBin * bin, GstElementFlags flags)
1410 g_return_if_fail (GST_IS_BIN (bin));
1412 GST_OBJECT_LOCK (bin);
1413 bin->priv->suppressed_flags = bin->priv->suppressed_flags | flags;
1414 GST_OBJECT_UNLOCK (bin);
1416 GST_DEBUG_OBJECT (bin, "Set suppressed flags(0x%x) to bin '%s'", flags,
1417 GST_ELEMENT_NAME (bin));
1421 * gst_bin_get_suppressed_flags:
1424 * Return the suppressed flags of the bin.
1428 * Returns: the bin's suppressed #GstElementFlags.
1433 gst_bin_get_suppressed_flags (GstBin * bin)
1435 GstElementFlags res;
1437 g_return_val_if_fail (GST_IS_BIN (bin), 0);
1439 GST_OBJECT_LOCK (bin);
1440 res = bin->priv->suppressed_flags;
1441 GST_OBJECT_UNLOCK (bin);
1446 /* signal vfunc, will be called when a new element was added */
1448 gst_bin_deep_element_added_func (GstBin * bin, GstBin * sub_bin,
1453 parent_bin = (GstBin *) gst_object_get_parent (GST_OBJECT_CAST (bin));
1454 if (parent_bin == NULL) {
1455 GST_LOG_OBJECT (bin, "no parent, reached top-level");
1459 GST_LOG_OBJECT (parent_bin, "emitting deep-element-added for element "
1460 "%" GST_PTR_FORMAT " which has just been added to %" GST_PTR_FORMAT,
1463 g_signal_emit (parent_bin, gst_bin_signals[DEEP_ELEMENT_ADDED], 0, sub_bin,
1466 gst_object_unref (parent_bin);
1469 /* signal vfunc, will be called when an element was removed */
1471 gst_bin_deep_element_removed_func (GstBin * bin, GstBin * sub_bin,
1476 parent_bin = (GstBin *) gst_object_get_parent (GST_OBJECT_CAST (bin));
1477 if (parent_bin == NULL) {
1478 GST_LOG_OBJECT (bin, "no parent, reached top-level");
1482 GST_LOG_OBJECT (parent_bin, "emitting deep-element-removed for element "
1483 "%" GST_PTR_FORMAT " which has just been removed from %" GST_PTR_FORMAT,
1486 g_signal_emit (parent_bin, gst_bin_signals[DEEP_ELEMENT_REMOVED], 0, sub_bin,
1489 gst_object_unref (parent_bin);
1495 * @element: (transfer full): the #GstElement to add
1497 * Adds the given element to the bin. Sets the element's parent, and thus
1498 * takes ownership of the element. An element can only be added to one bin.
1500 * If the element's pads are linked to other pads, the pads will be unlinked
1501 * before the element is added to the bin.
1503 * > When you add an element to an already-running pipeline, you will have to
1504 * > take care to set the state of the newly-added element to the desired
1505 * > state (usually PLAYING or PAUSED, same you set the pipeline to originally)
1506 * > with gst_element_set_state(), or use gst_element_sync_state_with_parent().
1507 * > The bin or pipeline will not take care of this for you.
1511 * Returns: %TRUE if the element could be added, %FALSE if
1512 * the bin does not want to accept the element.
1515 gst_bin_add (GstBin * bin, GstElement * element)
1517 GstBinClass *bclass;
1520 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1521 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1522 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1524 bclass = GST_BIN_GET_CLASS (bin);
1526 if (G_UNLIKELY (bclass->add_element == NULL))
1529 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1530 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1531 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1533 GST_TRACER_BIN_ADD_PRE (bin, element);
1534 result = bclass->add_element (bin, element);
1535 GST_TRACER_BIN_ADD_POST (bin, element, result);
1539 /* ERROR handling */
1542 g_warning ("adding elements to bin '%s' is not supported",
1543 GST_ELEMENT_NAME (bin));
1544 gst_object_ref_sink (element);
1545 gst_object_unref (element);
1550 /* remove an element from the bin
1555 gst_bin_remove_func (GstBin * bin, GstElement * element)
1559 gboolean is_sink, is_source, provides_clock, requires_clock;
1560 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1561 GstMessage *clock_message = NULL;
1562 GstClock **provided_clock_p;
1563 GstElement **clock_provider_p;
1565 gboolean other_async, this_async, have_no_preroll;
1566 GstStateChangeReturn ret;
1568 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1570 /* we obviously can't remove ourself from ourself */
1571 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1572 goto removing_itself;
1574 GST_OBJECT_LOCK (bin);
1576 GST_OBJECT_LOCK (element);
1577 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1579 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1582 /* remove the parent ref */
1583 GST_OBJECT_PARENT (element) = NULL;
1585 /* grab element name so we can print it */
1586 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1587 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1589 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1591 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1592 GST_OBJECT_UNLOCK (element);
1596 othersource = FALSE;
1597 otherprovider = FALSE;
1598 otherrequirer = FALSE;
1599 have_no_preroll = FALSE;
1600 /* iterate the elements, we collect which ones are async and no_preroll. We
1601 * also remove the element when we find it. */
1602 for (walk = bin->children; walk; walk = next) {
1603 GstElement *child = GST_ELEMENT_CAST (walk->data);
1605 next = g_list_next (walk);
1607 if (child == element) {
1609 /* remove the element */
1610 bin->children = g_list_delete_link (bin->children, walk);
1612 gboolean child_sink, child_source, child_provider, child_requirer;
1614 GST_OBJECT_LOCK (child);
1615 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1616 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1618 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1620 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1621 /* when we remove a sink, check if there are other sinks. */
1622 if (is_sink && !othersink && child_sink)
1624 if (is_source && !othersource && child_source)
1626 if (provides_clock && !otherprovider && child_provider)
1627 otherprovider = TRUE;
1628 if (requires_clock && !otherrequirer && child_requirer)
1629 otherrequirer = TRUE;
1630 /* check if we have NO_PREROLL children */
1631 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1632 have_no_preroll = TRUE;
1633 GST_OBJECT_UNLOCK (child);
1637 /* the element must have been in the bin's list of children */
1638 if (G_UNLIKELY (!found))
1641 /* we now removed the element from the list of elements, increment the cookie
1642 * so that others can detect a change in the children list. */
1644 bin->children_cookie++;
1645 if (!GST_BIN_IS_NO_RESYNC (bin))
1646 bin->priv->structure_cookie++;
1648 if (is_sink && !othersink
1649 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SINK)) {
1650 /* we're not a sink anymore */
1651 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1652 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1654 if (is_source && !othersource
1655 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_SOURCE)) {
1656 /* we're not a source anymore */
1657 GST_DEBUG_OBJECT (bin, "we removed the last source");
1658 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1660 if (provides_clock && !otherprovider
1661 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_PROVIDE_CLOCK)) {
1662 /* we're not a clock provider anymore */
1663 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1664 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1666 if (requires_clock && !otherrequirer
1667 && !(bin->priv->suppressed_flags & GST_ELEMENT_FLAG_REQUIRE_CLOCK)) {
1668 /* we're not a clock requirer anymore */
1669 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1670 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1673 /* if the clock provider for this element is removed, we lost
1674 * the clock as well, we need to inform the parent of this
1675 * so that it can select a new clock */
1676 if (bin->clock_provider == element) {
1677 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1678 bin->clock_dirty = TRUE;
1680 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1681 provided_clock_p = &bin->provided_clock;
1682 clock_provider_p = &bin->clock_provider;
1683 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1684 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1687 /* remove messages for the element, if there was a pending ASYNC_START
1688 * message we must see if removing the element caused the bin to lose its
1691 other_async = FALSE;
1692 for (walk = bin->messages; walk; walk = next) {
1693 GstMessage *message = (GstMessage *) walk->data;
1694 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1697 next = g_list_next (walk);
1700 switch (GST_MESSAGE_TYPE (message)) {
1701 case GST_MESSAGE_ASYNC_START:
1707 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1709 case GST_MESSAGE_STRUCTURE_CHANGE:
1713 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1715 /* it's unlikely that this message is still in the list of messages
1716 * because this would mean that a link/unlink is busy in another thread
1717 * while we remove the element. We still have to remove the message
1718 * because we might not receive the done message anymore when the element
1719 * is removed from the bin. */
1720 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1721 if (owner == element)
1732 /* delete all message types */
1733 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1734 message, elem_name);
1735 bin->messages = g_list_delete_link (bin->messages, walk);
1736 gst_message_unref (message);
1740 /* get last return */
1741 ret = GST_STATE_RETURN (bin);
1743 /* no need to update the state if we are in error */
1744 if (ret == GST_STATE_CHANGE_FAILURE)
1745 goto no_state_recalc;
1747 if (!other_async && this_async) {
1748 /* all other elements were not async and we removed the async one,
1749 * handle the async-done case because we are not async anymore now. */
1750 GST_DEBUG_OBJECT (bin,
1751 "we removed the last async element, have no_preroll %d",
1754 /* the current state return of the bin depends on if there are no_preroll
1755 * elements in the pipeline or not */
1756 if (have_no_preroll)
1757 ret = GST_STATE_CHANGE_NO_PREROLL;
1759 ret = GST_STATE_CHANGE_SUCCESS;
1761 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1763 GST_DEBUG_OBJECT (bin,
1764 "recalc state preroll: %d, other async: %d, this async %d",
1765 have_no_preroll, other_async, this_async);
1767 if (have_no_preroll) {
1768 ret = GST_STATE_CHANGE_NO_PREROLL;
1769 } else if (other_async) {
1770 /* there are other async elements and we were not doing an async state
1771 * change, change our pending state and go async */
1772 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1773 GST_STATE_NEXT (bin) = GST_STATE (bin);
1774 GST_STATE_PENDING (bin) = GST_STATE (bin);
1776 ret = GST_STATE_CHANGE_ASYNC;
1778 GST_STATE_RETURN (bin) = ret;
1782 gst_element_set_bus (element, NULL);
1783 /* Clear the clock we provided to the element */
1784 gst_element_set_clock (element, NULL);
1785 GST_OBJECT_UNLOCK (bin);
1788 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1790 /* unlink all linked pads */
1791 it = gst_element_iterate_pads (element);
1792 while (gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads,
1793 NULL) == GST_ITERATOR_RESYNC)
1794 gst_iterator_resync (it);
1795 gst_iterator_free (it);
1797 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1800 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1801 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1804 gst_bin_do_deep_add_remove (bin, gst_bin_signals[DEEP_ELEMENT_REMOVED],
1805 "deep-element-removed", element);
1808 /* element is really out of our control now */
1809 gst_object_unref (element);
1813 /* ERROR handling */
1816 GST_OBJECT_LOCK (bin);
1817 g_warning ("Cannot remove bin '%s' from itself", GST_ELEMENT_NAME (bin));
1818 GST_OBJECT_UNLOCK (bin);
1823 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1824 GST_ELEMENT_NAME (bin));
1825 GST_OBJECT_UNLOCK (element);
1826 GST_OBJECT_UNLOCK (bin);
1835 * @element: (transfer none): the #GstElement to remove
1837 * Removes the element from the bin, unparenting it as well.
1838 * Unparenting the element means that the element will be dereferenced,
1839 * so if the bin holds the only reference to the element, the element
1840 * will be freed in the process of removing it from the bin. If you
1841 * want the element to still exist after removing, you need to call
1842 * gst_object_ref() before removing it from the bin.
1844 * If the element's pads are linked to other pads, the pads will be unlinked
1845 * before the element is removed from the bin.
1849 * Returns: %TRUE if the element could be removed, %FALSE if
1850 * the bin does not want to remove the element.
1853 gst_bin_remove (GstBin * bin, GstElement * element)
1855 GstBinClass *bclass;
1858 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1859 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1860 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1862 bclass = GST_BIN_GET_CLASS (bin);
1864 if (G_UNLIKELY (bclass->remove_element == NULL))
1867 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1868 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1870 GST_TRACER_BIN_REMOVE_PRE (bin, element);
1871 result = bclass->remove_element (bin, element);
1872 GST_TRACER_BIN_REMOVE_POST (bin, result);
1876 /* ERROR handling */
1879 g_warning ("removing elements from bin '%s' is not supported",
1880 GST_ELEMENT_NAME (bin));
1886 * gst_bin_iterate_elements:
1889 * Gets an iterator for the elements in this bin.
1891 * MT safe. Caller owns returned value.
1893 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1897 gst_bin_iterate_elements (GstBin * bin)
1899 GstIterator *result;
1901 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1903 GST_OBJECT_LOCK (bin);
1904 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1905 GST_OBJECT_GET_LOCK (bin),
1906 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1907 GST_OBJECT_UNLOCK (bin);
1912 static GstIteratorItem
1913 iterate_child_recurse (GstIterator * it, const GValue * item)
1915 GstElement *child = g_value_get_object (item);
1917 if (GST_IS_BIN (child)) {
1918 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1920 gst_iterator_push (it, other);
1922 return GST_ITERATOR_ITEM_PASS;
1926 * gst_bin_iterate_recurse:
1929 * Gets an iterator for the elements in this bin.
1930 * This iterator recurses into GstBin children.
1932 * MT safe. Caller owns returned value.
1934 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1938 gst_bin_iterate_recurse (GstBin * bin)
1940 GstIterator *result;
1942 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1944 GST_OBJECT_LOCK (bin);
1945 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1946 GST_OBJECT_GET_LOCK (bin),
1947 &bin->children_cookie,
1949 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1950 GST_OBJECT_UNLOCK (bin);
1955 /* returns 0 when TRUE because this is a GCompareFunc */
1958 bin_element_is_sink (GstElement * child, GstBin * bin)
1962 /* we lock the child here for the remainder of the function to
1963 * get its name and flag safely. */
1964 GST_OBJECT_LOCK (child);
1965 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1967 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1968 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1970 GST_OBJECT_UNLOCK (child);
1971 return is_sink ? 0 : 1;
1975 sink_iterator_filter (const GValue * vchild, GValue * vbin)
1977 GstBin *bin = g_value_get_object (vbin);
1978 GstElement *child = g_value_get_object (vchild);
1980 return (bin_element_is_sink (child, bin));
1984 * gst_bin_iterate_sinks:
1987 * Gets an iterator for all elements in the bin that have the
1988 * #GST_ELEMENT_FLAG_SINK flag set.
1990 * MT safe. Caller owns returned value.
1992 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1996 gst_bin_iterate_sinks (GstBin * bin)
1998 GstIterator *children;
1999 GstIterator *result;
2000 GValue vbin = { 0, };
2002 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2004 g_value_init (&vbin, GST_TYPE_BIN);
2005 g_value_set_object (&vbin, bin);
2007 children = gst_bin_iterate_elements (bin);
2008 result = gst_iterator_filter (children,
2009 (GCompareFunc) sink_iterator_filter, &vbin);
2011 g_value_unset (&vbin);
2016 /* returns 0 when TRUE because this is a GCompareFunc */
2019 bin_element_is_src (GstElement * child, GstBin * bin)
2023 /* we lock the child here for the remainder of the function to
2024 * get its name and other info safely. */
2025 GST_OBJECT_LOCK (child);
2026 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
2028 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2029 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
2031 GST_OBJECT_UNLOCK (child);
2032 return is_src ? 0 : 1;
2036 src_iterator_filter (const GValue * vchild, GValue * vbin)
2038 GstBin *bin = g_value_get_object (vbin);
2039 GstElement *child = g_value_get_object (vchild);
2041 return (bin_element_is_src (child, bin));
2045 * gst_bin_iterate_sources:
2048 * Gets an iterator for all elements in the bin that have the
2049 * #GST_ELEMENT_FLAG_SOURCE flag set.
2051 * MT safe. Caller owns returned value.
2053 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
2057 gst_bin_iterate_sources (GstBin * bin)
2059 GstIterator *children;
2060 GstIterator *result;
2061 GValue vbin = { 0, };
2063 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2065 g_value_init (&vbin, GST_TYPE_BIN);
2066 g_value_set_object (&vbin, bin);
2068 children = gst_bin_iterate_elements (bin);
2069 result = gst_iterator_filter (children,
2070 (GCompareFunc) src_iterator_filter, &vbin);
2072 g_value_unset (&vbin);
2080 static GstStateChangeReturn
2081 gst_bin_get_state_func (GstElement * element, GstState * state,
2082 GstState * pending, GstClockTime timeout)
2084 GstStateChangeReturn ret;
2086 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
2089 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
2095 /***********************************************
2096 * Topologically sorted iterator
2097 * see http://en.wikipedia.org/wiki/Topological_sorting
2099 * For each element in the graph, an entry is kept in a HashTable
2100 * with its number of srcpad connections (degree).
2101 * We then change state of all elements without dependencies
2102 * (degree 0) and decrement the degree of all elements connected
2103 * on the sinkpads. When an element reaches degree 0, its state is
2105 * When all elements are handled the algorithm stops.
2107 typedef struct _GstBinSortIterator
2110 GQueue queue; /* elements queued for state change */
2111 GstBin *bin; /* bin we iterate */
2112 gint mode; /* adding or removing dependency */
2113 GstElement *best; /* next element with least dependencies */
2114 gint best_deg; /* best degree */
2115 GHashTable *hash; /* hashtable with element dependencies */
2116 gboolean dirty; /* we detected structure change */
2117 } GstBinSortIterator;
2120 copy_to_queue (gpointer data, gpointer user_data)
2122 GstElement *element = data;
2123 GQueue *queue = user_data;
2125 gst_object_ref (element);
2126 g_queue_push_tail (queue, element);
2130 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
2131 GstBinSortIterator * copy)
2133 GHashTableIter iter;
2134 gpointer key, value;
2136 g_queue_init (©->queue);
2137 g_queue_foreach ((GQueue *) & it->queue, copy_to_queue, ©->queue);
2139 copy->bin = gst_object_ref (it->bin);
2141 copy->best = gst_object_ref (it->best);
2143 copy->hash = g_hash_table_new (NULL, NULL);
2144 g_hash_table_iter_init (&iter, it->hash);
2145 while (g_hash_table_iter_next (&iter, &key, &value))
2146 g_hash_table_insert (copy->hash, key, value);
2149 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
2150 #define HASH_SET_DEGREE(bit, elem, deg) \
2151 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
2152 #define HASH_GET_DEGREE(bit, elem) \
2153 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
2155 /* add element to queue of next elements in the iterator.
2156 * We push at the tail to give higher priority elements a
2159 add_to_queue (GstBinSortIterator * bit, GstElement * element)
2161 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
2162 GST_ELEMENT_NAME (element));
2163 gst_object_ref (element);
2164 g_queue_push_tail (&bit->queue, element);
2165 HASH_SET_DEGREE (bit, element, -1);
2169 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
2173 if ((find = g_queue_find (&bit->queue, element))) {
2174 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
2175 GST_ELEMENT_NAME (element));
2177 g_queue_delete_link (&bit->queue, find);
2178 gst_object_unref (element);
2180 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
2181 GST_ELEMENT_NAME (element));
2185 /* clear the queue, unref all objects as we took a ref when
2186 * we added them to the queue */
2188 clear_queue (GQueue * queue)
2192 while ((p = g_queue_pop_head (queue)))
2193 gst_object_unref (p);
2196 /* set all degrees to 0. Elements marked as a sink are
2197 * added to the queue immediately. Since we only look at the SINK flag of the
2198 * element, it is possible that we add non-sinks to the queue. These will be
2199 * removed from the queue again when we can prove that it provides data for some
2202 reset_degree (GstElement * element, GstBinSortIterator * bit)
2206 /* sinks are added right away */
2207 GST_OBJECT_LOCK (element);
2208 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
2209 GST_OBJECT_UNLOCK (element);
2212 add_to_queue (bit, element);
2214 /* others are marked with 0 and handled when sinks are done */
2215 HASH_SET_DEGREE (bit, element, 0);
2219 /* adjust the degree of all elements connected to the given
2220 * element. If a degree of an element drops to 0, it is
2221 * added to the queue of elements to schedule next.
2223 * We have to make sure not to cross the bin boundary this element
2227 update_degree (GstElement * element, GstBinSortIterator * bit)
2229 gboolean linked = FALSE;
2231 GST_OBJECT_LOCK (element);
2232 /* don't touch degree if element has no sinkpads */
2233 if (element->numsinkpads != 0) {
2234 /* loop over all sinkpads, decrement degree for all connected
2235 * elements in this bin */
2238 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
2241 pad = GST_PAD_CAST (pads->data);
2243 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
2244 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
2245 GST_MESSAGE_STRUCTURE_CHANGE))) {
2246 /* mark the iterator as dirty because we won't be updating the degree
2247 * of the peer parent now. This would result in the 'loop detected'
2248 * later on because the peer parent element could become the best next
2249 * element with a degree > 0. We will simply continue our state
2250 * changes and we'll eventually resync when the unlink completed and
2251 * the iterator cookie is updated. */
2256 if ((peer = gst_pad_get_peer (pad))) {
2257 GstElement *peer_element;
2259 if ((peer_element = gst_pad_get_parent_element (peer))) {
2260 GST_OBJECT_LOCK (peer_element);
2261 /* check that we don't go outside of this bin */
2262 if (GST_OBJECT_CAST (peer_element)->parent ==
2263 GST_OBJECT_CAST (bit->bin)) {
2264 gint old_deg, new_deg;
2266 old_deg = HASH_GET_DEGREE (bit, peer_element);
2268 /* check to see if we added an element as sink that was not really a
2269 * sink because it was connected to some other element. */
2270 if (old_deg == -1) {
2271 remove_from_queue (bit, peer_element);
2274 new_deg = old_deg + bit->mode;
2276 GST_DEBUG_OBJECT (bit->bin,
2277 "change element %s, degree %d->%d, linked to %s",
2278 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
2279 GST_ELEMENT_NAME (element));
2281 /* update degree, it is possible that an element was in 0 and
2282 * reaches -1 here. This would mean that the element had no sinkpads
2283 * but became linked while the state change was happening. We will
2284 * resync on this with the structure change message. */
2286 /* degree hit 0, add to queue */
2287 add_to_queue (bit, peer_element);
2289 HASH_SET_DEGREE (bit, peer_element, new_deg);
2293 GST_OBJECT_UNLOCK (peer_element);
2294 gst_object_unref (peer_element);
2296 gst_object_unref (peer);
2301 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2302 GST_ELEMENT_NAME (element));
2304 GST_OBJECT_UNLOCK (element);
2307 /* find the next best element not handled yet. This is the one
2308 * with the lowest non-negative degree */
2310 find_element (GstElement * element, GstBinSortIterator * bit)
2314 /* element is already handled */
2315 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2318 /* first element or element with smaller degree */
2319 if (bit->best == NULL || bit->best_deg > degree) {
2320 bit->best = element;
2321 bit->best_deg = degree;
2325 /* get next element in iterator. */
2326 static GstIteratorResult
2327 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2330 GstBin *bin = bit->bin;
2332 /* empty queue, we have to find a next best element */
2333 if (g_queue_is_empty (&bit->queue)) {
2335 bit->best_deg = G_MAXINT;
2336 g_list_foreach (bin->children, (GFunc) find_element, bit);
2337 if ((best = bit->best)) {
2338 /* when we detected an unlink, don't warn because our degrees might be
2339 * screwed up. We will resync later */
2340 if (bit->best_deg != 0 && !bit->dirty) {
2341 /* we don't fail on this one yet */
2342 GST_WARNING_OBJECT (bin, "loop dected in graph");
2343 g_warning ("loop detected in the graph of bin '%s'!!",
2344 GST_ELEMENT_NAME (bin));
2346 /* best unhandled element, schedule as next element */
2347 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2348 GST_ELEMENT_NAME (best));
2349 HASH_SET_DEGREE (bit, best, -1);
2350 g_value_set_object (result, best);
2352 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2353 /* no more unhandled elements, we are done */
2354 return GST_ITERATOR_DONE;
2357 /* everything added to the queue got reffed */
2358 best = g_queue_pop_head (&bit->queue);
2359 g_value_set_object (result, best);
2360 gst_object_unref (best);
2363 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2364 /* update degrees of linked elements */
2365 update_degree (best, bit);
2367 return GST_ITERATOR_OK;
2370 /* clear queues, recalculate the degrees and restart. */
2372 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2374 GstBin *bin = bit->bin;
2376 GST_DEBUG_OBJECT (bin, "resync");
2378 clear_queue (&bit->queue);
2380 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2381 /* calc degrees, incrementing */
2383 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2384 /* for the rest of the function we decrement the degrees */
2388 /* clear queues, unref bin and free iterator. */
2390 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2392 GstBin *bin = bit->bin;
2394 GST_DEBUG_OBJECT (bin, "free");
2395 clear_queue (&bit->queue);
2396 g_hash_table_destroy (bit->hash);
2397 gst_object_unref (bin);
2400 /* should be called with the bin LOCK held */
2401 static GstIterator *
2402 gst_bin_sort_iterator_new (GstBin * bin)
2404 GstBinSortIterator *result;
2406 /* we don't need an ItemFunction because we ref the items in the _next
2408 result = (GstBinSortIterator *)
2409 gst_iterator_new (sizeof (GstBinSortIterator),
2411 GST_OBJECT_GET_LOCK (bin),
2412 &bin->priv->structure_cookie,
2413 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2414 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2415 (GstIteratorItemFunction) NULL,
2416 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2417 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2418 g_queue_init (&result->queue);
2419 result->hash = g_hash_table_new (NULL, NULL);
2420 gst_object_ref (bin);
2422 gst_bin_sort_iterator_resync (result);
2424 return (GstIterator *) result;
2428 * gst_bin_iterate_sorted:
2431 * Gets an iterator for the elements in this bin in topologically
2432 * sorted order. This means that the elements are returned from
2433 * the most downstream elements (sinks) to the sources.
2435 * This function is used internally to perform the state changes
2436 * of the bin elements and for clock selection.
2438 * MT safe. Caller owns returned value.
2440 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
2444 gst_bin_iterate_sorted (GstBin * bin)
2446 GstIterator *result;
2448 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2450 GST_OBJECT_LOCK (bin);
2451 result = gst_bin_sort_iterator_new (bin);
2452 GST_OBJECT_UNLOCK (bin);
2457 static GstStateChangeReturn
2458 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2459 GstClockTime base_time, GstClockTime start_time, GstState current,
2462 GstStateChangeReturn ret;
2463 GstState child_current, child_pending;
2467 GST_STATE_LOCK (element);
2469 GST_OBJECT_LOCK (element);
2470 /* set base_time and start time on child */
2471 GST_ELEMENT_START_TIME (element) = start_time;
2472 element->base_time = base_time;
2473 /* peel off the locked flag */
2474 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2475 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2476 ret = GST_STATE_RETURN (element);
2477 child_current = GST_STATE (element);
2478 child_pending = GST_STATE_PENDING (element);
2479 GST_OBJECT_UNLOCK (element);
2481 /* skip locked elements */
2482 if (G_UNLIKELY (locked))
2485 /* if the element was no preroll, just start changing the state regardless
2486 * if it had async elements (in the case of a bin) because they won't preroll
2488 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2489 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2493 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2494 "current %s pending %s, desired next %s",
2495 gst_element_state_get_name (child_current),
2496 gst_element_state_get_name (child_pending),
2497 gst_element_state_get_name (next));
2499 /* always recurse into bins so that we can set the base time */
2500 if (GST_IS_BIN (element))
2503 /* Try not to change the state of elements that are already in the state we're
2505 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2506 /* child is already at the requested state, return previous return. Note that
2507 * if the child has a pending state to next, we will still call the
2508 * set_state function */
2510 } else if (next > current) {
2511 /* upward state change */
2512 if (child_pending == GST_STATE_VOID_PENDING) {
2513 /* .. and the child is not busy doing anything */
2514 if (child_current > next) {
2515 /* .. and is already past the requested state, assume it got there
2517 ret = GST_STATE_CHANGE_SUCCESS;
2520 } else if (child_pending > child_current) {
2521 /* .. and the child is busy going upwards */
2522 if (child_current >= next) {
2523 /* .. and is already past the requested state, assume it got there
2525 ret = GST_STATE_CHANGE_SUCCESS;
2529 /* .. and the child is busy going downwards */
2530 if (child_current > next) {
2531 /* .. and is already past the requested state, assume it got there
2533 ret = GST_STATE_CHANGE_SUCCESS;
2537 } else if (next < current) {
2538 /* downward state change */
2539 if (child_pending == GST_STATE_VOID_PENDING) {
2540 /* .. and the child is not busy doing anything */
2541 if (child_current < next) {
2542 /* .. and is already past the requested state, assume it got there
2544 ret = GST_STATE_CHANGE_SUCCESS;
2547 } else if (child_pending < child_current) {
2548 /* .. and the child is busy going downwards */
2549 if (child_current <= next) {
2550 /* .. and is already past the requested state, assume it got there
2552 ret = GST_STATE_CHANGE_SUCCESS;
2556 /* .. and the child is busy going upwards */
2557 if (child_current < next) {
2558 /* .. and is already past the requested state, assume it got there
2560 ret = GST_STATE_CHANGE_SUCCESS;
2567 GST_OBJECT_LOCK (bin);
2568 /* the element was busy with an upwards async state change, we must wait for
2569 * an ASYNC_DONE message before we attemp to change the state. */
2571 find_message (bin, GST_OBJECT_CAST (element),
2572 GST_MESSAGE_ASYNC_START))) {
2573 #ifndef GST_DISABLE_GST_DEBUG
2574 GstMessage *message = GST_MESSAGE_CAST (found->data);
2576 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2577 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2579 /* only wait for upward state changes */
2580 if (next > current) {
2581 /* We found an async element check if we can force its state to change or
2582 * if we have to wait for it to preroll. */
2586 GST_OBJECT_UNLOCK (bin);
2589 GST_DEBUG_OBJECT (bin,
2590 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2591 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2592 GST_TIME_ARGS (base_time));
2595 ret = gst_element_set_state (element, next);
2597 GST_STATE_UNLOCK (element);
2603 GST_DEBUG_OBJECT (element,
2604 "element is locked, return previous return %s",
2605 gst_element_state_change_return_get_name (ret));
2606 GST_STATE_UNLOCK (element);
2611 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2612 "skipping transition from %s to %s",
2613 gst_element_state_get_name (child_current),
2614 gst_element_state_get_name (next));
2615 GST_STATE_UNLOCK (element);
2620 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2621 GST_OBJECT_UNLOCK (bin);
2622 GST_STATE_UNLOCK (element);
2623 return GST_STATE_CHANGE_ASYNC;
2627 /* gst_iterator_fold functions for pads_activate
2628 * Stop the iterator if activating one pad failed, but only if that pad
2629 * has not been removed from the element. */
2631 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2633 GstPad *pad = g_value_get_object (vpad);
2634 gboolean cont = TRUE;
2636 if (!gst_pad_set_active (pad, *active)) {
2637 if (GST_PAD_PARENT (pad) != NULL) {
2639 g_value_set_boolean (ret, FALSE);
2646 /* returns false on error or early cutout of the fold, true if all
2647 * pads in @iter were (de)activated successfully. */
2649 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2651 GstIteratorResult ires;
2654 /* no need to unset this later, it's just a boolean */
2655 g_value_init (&ret, G_TYPE_BOOLEAN);
2656 g_value_set_boolean (&ret, TRUE);
2659 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2662 case GST_ITERATOR_RESYNC:
2663 /* need to reset the result again */
2664 g_value_set_boolean (&ret, TRUE);
2665 gst_iterator_resync (iter);
2667 case GST_ITERATOR_DONE:
2668 /* all pads iterated, return collected value */
2671 /* iterator returned _ERROR or premature end with _OK,
2672 * mark an error and exit */
2673 g_value_set_boolean (&ret, FALSE);
2678 /* return collected value */
2679 return g_value_get_boolean (&ret);
2682 /* is called with STATE_LOCK
2685 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2690 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2692 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2693 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2694 gst_iterator_free (iter);
2695 if (G_UNLIKELY (!fold_ok))
2698 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2705 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2711 * gst_bin_recalculate_latency:
2714 * Query @bin for the current latency using and reconfigures this latency to all the
2715 * elements with a LATENCY event.
2717 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2718 * is posted on the bus.
2720 * This function simply emits the 'do-latency' signal so any custom latency
2721 * calculations will be performed.
2723 * Returns: %TRUE if the latency could be queried and reconfigured.
2726 gst_bin_recalculate_latency (GstBin * bin)
2730 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2731 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2737 gst_bin_do_latency_func (GstBin * bin)
2740 GstElement *element;
2741 GstClockTime min_latency, max_latency;
2744 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2746 element = GST_ELEMENT_CAST (bin);
2748 GST_DEBUG_OBJECT (element, "querying latency");
2750 query = gst_query_new_latency ();
2751 if ((res = gst_element_query (element, query))) {
2754 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2756 GST_DEBUG_OBJECT (element,
2757 "got min latency %" GST_TIME_FORMAT ", max latency %"
2758 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2759 GST_TIME_ARGS (max_latency), live);
2761 if (max_latency < min_latency) {
2762 /* this is an impossible situation, some parts of the pipeline might not
2763 * work correctly. We post a warning for now. */
2764 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2765 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2766 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2767 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2770 /* configure latency on elements */
2771 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2773 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2774 GST_TIME_ARGS (min_latency));
2776 GST_WARNING_OBJECT (element,
2777 "did not really configure latency of %" GST_TIME_FORMAT,
2778 GST_TIME_ARGS (min_latency));
2781 /* this is not a real problem, we just don't configure any latency. */
2782 GST_WARNING_OBJECT (element, "failed to query latency");
2784 gst_query_unref (query);
2790 gst_bin_post_message (GstElement * element, GstMessage * msg)
2792 GstElementClass *pklass = (GstElementClass *) parent_class;
2795 ret = pklass->post_message (element, gst_message_ref (msg));
2797 if (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_STATE_CHANGED &&
2798 GST_MESSAGE_SRC (msg) == GST_OBJECT_CAST (element)) {
2799 GstState newstate, pending;
2801 gst_message_parse_state_changed (msg, NULL, &newstate, &pending);
2802 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING) {
2803 GST_BIN_CAST (element)->priv->posted_playing = TRUE;
2804 bin_do_eos (GST_BIN_CAST (element));
2806 GST_BIN_CAST (element)->priv->posted_playing = FALSE;
2810 gst_message_unref (msg);
2816 reset_state (const GValue * data, gpointer user_data)
2818 GstElement *e = g_value_get_object (data);
2819 GstState state = GPOINTER_TO_INT (user_data);
2821 if (gst_element_set_state (e, state) == GST_STATE_CHANGE_FAILURE)
2822 GST_WARNING_OBJECT (e, "Failed to switch back down to %s",
2823 gst_element_state_get_name (state));
2826 static GstStateChangeReturn
2827 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2830 GstStateChangeReturn ret;
2831 GstState current, next;
2832 gboolean have_async;
2833 gboolean have_no_preroll;
2834 GstClockTime base_time, start_time;
2837 GValue data = { 0, };
2839 /* we don't need to take the STATE_LOCK, it is already taken */
2840 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2841 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2843 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2844 "changing state of children from %s to %s",
2845 gst_element_state_get_name (current), gst_element_state_get_name (next));
2847 bin = GST_BIN_CAST (element);
2850 case GST_STATE_PLAYING:
2852 gboolean toplevel, asynchandling;
2854 GST_OBJECT_LOCK (bin);
2855 toplevel = BIN_IS_TOPLEVEL (bin);
2856 asynchandling = bin->priv->asynchandling;
2857 GST_OBJECT_UNLOCK (bin);
2860 gst_bin_recalculate_latency (bin);
2862 gst_element_post_message (element,
2863 gst_message_new_latency (GST_OBJECT_CAST (element)));
2866 case GST_STATE_PAUSED:
2867 /* Clear EOS list on next PAUSED */
2868 GST_OBJECT_LOCK (bin);
2869 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2870 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2871 bin->priv->posted_eos = FALSE;
2872 if (current == GST_STATE_READY)
2873 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2874 GST_OBJECT_UNLOCK (bin);
2875 if (current == GST_STATE_READY)
2876 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2877 goto activate_failure;
2879 case GST_STATE_READY:
2880 /* Clear message list on next READY */
2881 GST_OBJECT_LOCK (bin);
2882 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2883 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2884 GST_OBJECT_UNLOCK (bin);
2885 /* We might not have reached PAUSED yet due to async errors,
2886 * make sure to always deactivate the pads nonetheless */
2887 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2888 goto activate_failure;
2890 case GST_STATE_NULL:
2891 /* Clear message list on next NULL */
2892 GST_OBJECT_LOCK (bin);
2893 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2894 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2895 GST_OBJECT_UNLOCK (bin);
2896 if (current == GST_STATE_READY) {
2897 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2898 goto activate_failure;
2905 /* this flag is used to make the async state changes return immediately. We
2906 * don't want them to interfere with this state change */
2907 GST_OBJECT_LOCK (bin);
2908 bin->polling = TRUE;
2909 GST_OBJECT_UNLOCK (bin);
2911 /* iterate in state change order */
2912 it = gst_bin_iterate_sorted (bin);
2914 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2915 * Note how we don't reset this value when a resync happens, the reason being
2916 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2917 * even after a resync when the async element is gone */
2921 /* take base_time */
2922 base_time = gst_element_get_base_time (element);
2923 start_time = gst_element_get_start_time (element);
2925 have_no_preroll = FALSE;
2929 switch (gst_iterator_next (it, &data)) {
2930 case GST_ITERATOR_OK:
2934 child = g_value_get_object (&data);
2936 /* set state and base_time now */
2937 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2941 case GST_STATE_CHANGE_SUCCESS:
2942 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2943 "child '%s' changed state to %d(%s) successfully",
2944 GST_ELEMENT_NAME (child), next,
2945 gst_element_state_get_name (next));
2947 case GST_STATE_CHANGE_ASYNC:
2949 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2950 "child '%s' is changing state asynchronously to %s",
2951 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2955 case GST_STATE_CHANGE_FAILURE:{
2958 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2959 "child '%s' failed to go to state %d(%s)",
2960 GST_ELEMENT_NAME (child),
2961 next, gst_element_state_get_name (next));
2963 /* Only fail if the child is still inside
2964 * this bin. It might've been removed already
2965 * because of the error by the bin subclass
2966 * to ignore the error. */
2967 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2968 if (parent == GST_OBJECT_CAST (element)) {
2969 /* element is still in bin, really error now */
2970 gst_object_unref (parent);
2973 /* child removed from bin, let the resync code redo the state
2975 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2976 "child '%s' was removed from the bin",
2977 GST_ELEMENT_NAME (child));
2980 gst_object_unref (parent);
2984 case GST_STATE_CHANGE_NO_PREROLL:
2985 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2986 "child '%s' changed state to %d(%s) successfully without preroll",
2987 GST_ELEMENT_NAME (child), next,
2988 gst_element_state_get_name (next));
2989 have_no_preroll = TRUE;
2992 g_assert_not_reached ();
2995 g_value_reset (&data);
2998 case GST_ITERATOR_RESYNC:
2999 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
3000 gst_iterator_resync (it);
3003 case GST_ITERATOR_DONE:
3004 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
3010 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
3011 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
3014 if (have_no_preroll) {
3015 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3016 "we have NO_PREROLL elements %s -> NO_PREROLL",
3017 gst_element_state_change_return_get_name (ret));
3018 ret = GST_STATE_CHANGE_NO_PREROLL;
3019 } else if (have_async) {
3020 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3021 "we have ASYNC elements %s -> ASYNC",
3022 gst_element_state_change_return_get_name (ret));
3023 ret = GST_STATE_CHANGE_ASYNC;
3027 g_value_unset (&data);
3028 gst_iterator_free (it);
3030 GST_OBJECT_LOCK (bin);
3031 bin->polling = FALSE;
3032 /* it's possible that we did not get ASYNC from the children while the bin is
3033 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
3034 * itself as the source. In that case we still want to check if the state
3035 * change completed. */
3036 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
3037 /* no element returned ASYNC and there are no pending async_done messages,
3038 * we can just complete. */
3039 GST_DEBUG_OBJECT (bin, "no async elements");
3042 /* when we get here an ASYNC element was found */
3043 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
3044 /* we ignore ASYNC state changes when we go to READY or NULL */
3045 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
3046 gst_element_state_get_name (GST_STATE_TARGET (bin)));
3050 GST_DEBUG_OBJECT (bin, "check async elements");
3051 /* check if all elements managed to commit their state already */
3052 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3053 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
3054 * all the elements commited their state while we were doing the state
3055 * change. We will still return ASYNC for consistency but we commit the
3056 * state already so that a _get_state() will return immediately. */
3057 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3059 GST_DEBUG_OBJECT (bin, "async elements commited");
3060 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
3061 GST_CLOCK_TIME_NONE);
3065 bin->priv->pending_async_done = FALSE;
3066 GST_OBJECT_UNLOCK (bin);
3068 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
3069 "done changing bin's state from %s to %s, now in %s, ret %s",
3070 gst_element_state_get_name (current),
3071 gst_element_state_get_name (next),
3072 gst_element_state_get_name (GST_STATE (element)),
3073 gst_element_state_change_return_get_name (ret));
3080 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
3081 "failure (de)activating src pads");
3082 return GST_STATE_CHANGE_FAILURE;
3087 if (current < next) {
3088 GstIterator *it = gst_bin_iterate_sorted (GST_BIN (element));
3089 GstIteratorResult ret;
3091 GST_DEBUG_OBJECT (element,
3092 "Bin failed to change state, switching children back to %s",
3093 gst_element_state_get_name (current));
3096 gst_iterator_foreach (it, &reset_state, GINT_TO_POINTER (current));
3097 if (ret != GST_ITERATOR_RESYNC)
3099 gst_iterator_resync (it);
3101 gst_iterator_free (it);
3108 * This function is a utility event handler. It will send the event to all sinks
3109 * or sources and appropriate ghost pads depending on the event-direction.
3111 * Applications are free to override this behaviour and implement their own
3112 * handler, but this will work for pretty much all cases in practice.
3115 gst_bin_send_event (GstElement * element, GstEvent * event)
3117 GstBin *bin = GST_BIN_CAST (element);
3119 gboolean res = TRUE;
3120 gboolean done = FALSE;
3121 GValue data = { 0, };
3123 if (GST_EVENT_IS_DOWNSTREAM (event)) {
3124 iter = gst_bin_iterate_sources (bin);
3125 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
3126 GST_EVENT_TYPE_NAME (event));
3128 iter = gst_bin_iterate_sinks (bin);
3129 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
3130 GST_EVENT_TYPE_NAME (event));
3134 switch (gst_iterator_next (iter, &data)) {
3135 case GST_ITERATOR_OK:
3137 GstElement *child = g_value_get_object (&data);
3139 gst_event_ref (event);
3140 res &= gst_element_send_event (child, event);
3142 GST_LOG_OBJECT (child, "After handling %s event: %d",
3143 GST_EVENT_TYPE_NAME (event), res);
3145 g_value_reset (&data);
3148 case GST_ITERATOR_RESYNC:
3149 gst_iterator_resync (iter);
3152 case GST_ITERATOR_DONE:
3155 case GST_ITERATOR_ERROR:
3156 g_assert_not_reached ();
3160 g_value_unset (&data);
3161 gst_iterator_free (iter);
3163 if (GST_EVENT_IS_DOWNSTREAM (event)) {
3164 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
3165 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
3166 GST_EVENT_TYPE_NAME (event));
3168 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
3169 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
3170 GST_EVENT_TYPE_NAME (event));
3175 switch (gst_iterator_next (iter, &data)) {
3176 case GST_ITERATOR_OK:
3178 GstPad *pad = g_value_get_object (&data);
3180 gst_event_ref (event);
3181 res &= gst_pad_send_event (pad, event);
3182 GST_LOG_OBJECT (pad, "After handling %s event: %d",
3183 GST_EVENT_TYPE_NAME (event), res);
3186 case GST_ITERATOR_RESYNC:
3187 gst_iterator_resync (iter);
3190 case GST_ITERATOR_DONE:
3193 case GST_ITERATOR_ERROR:
3194 g_assert_not_reached ();
3199 g_value_unset (&data);
3200 gst_iterator_free (iter);
3201 gst_event_unref (event);
3206 /* this is the function called by the threadpool. When async elements commit
3207 * their state, this function will attempt to bring the bin to the next state.
3210 gst_bin_continue_func (GstBin * bin, BinContinueData * data)
3212 GstState current, next, pending;
3213 GstStateChange transition;
3215 pending = data->pending;
3217 GST_DEBUG_OBJECT (bin, "waiting for state lock");
3218 GST_STATE_LOCK (bin);
3220 GST_DEBUG_OBJECT (bin, "doing state continue");
3221 GST_OBJECT_LOCK (bin);
3223 /* if a new state change happened after this thread was scheduled, we return
3225 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
3228 current = GST_STATE (bin);
3229 next = GST_STATE_GET_NEXT (current, pending);
3230 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
3232 GST_STATE_NEXT (bin) = next;
3233 GST_STATE_PENDING (bin) = pending;
3235 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3236 GST_OBJECT_UNLOCK (bin);
3238 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3239 "continue state change %s to %s, final %s",
3240 gst_element_state_get_name (current),
3241 gst_element_state_get_name (next), gst_element_state_get_name (pending));
3243 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
3245 GST_STATE_UNLOCK (bin);
3246 GST_DEBUG_OBJECT (bin, "state continue done");
3252 GST_OBJECT_UNLOCK (bin);
3253 GST_STATE_UNLOCK (bin);
3254 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
3259 static GstBusSyncReply
3260 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
3262 GstBinClass *bclass;
3264 bclass = GST_BIN_GET_CLASS (bin);
3265 if (bclass->handle_message)
3266 bclass->handle_message (bin, message);
3268 gst_message_unref (message);
3270 return GST_BUS_DROP;
3274 free_bin_continue_data (BinContinueData * data)
3276 g_slice_free (BinContinueData, data);
3280 bin_push_state_continue (GstBin * bin, BinContinueData * data)
3282 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
3283 gst_element_call_async (GST_ELEMENT_CAST (bin),
3284 (GstElementCallAsyncFunc) gst_bin_continue_func, data,
3285 (GDestroyNotify) free_bin_continue_data);
3288 /* an element started an async state change, if we were not busy with a state
3289 * change, we perform a lost state.
3290 * This function is called with the OBJECT lock.
3293 bin_handle_async_start (GstBin * bin)
3295 GstState old_state, new_state;
3297 GstMessage *amessage = NULL;
3299 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3302 /* get our toplevel state */
3303 toplevel = BIN_IS_TOPLEVEL (bin);
3305 /* prepare an ASYNC_START message, we always post the start message even if we
3306 * are busy with a state change or when we are NO_PREROLL. */
3308 /* non toplevel bin, prepare async-start for the parent */
3309 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
3311 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
3314 /* async starts are ignored when we are NO_PREROLL */
3315 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
3316 goto was_no_preroll;
3318 old_state = GST_STATE (bin);
3320 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
3321 * PLAYING after optionally redistributing the base_time. */
3322 if (old_state > GST_STATE_PAUSED)
3323 new_state = GST_STATE_PAUSED;
3325 new_state = old_state;
3327 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3328 "lost state of %s, new %s", gst_element_state_get_name (old_state),
3329 gst_element_state_get_name (new_state));
3331 GST_STATE (bin) = new_state;
3332 GST_STATE_NEXT (bin) = new_state;
3333 GST_STATE_PENDING (bin) = new_state;
3334 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3335 GST_OBJECT_UNLOCK (bin);
3338 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
3343 /* post our ASYNC_START. */
3344 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
3345 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3347 GST_OBJECT_LOCK (bin);
3353 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3358 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3359 GST_OBJECT_UNLOCK (bin);
3364 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3365 GST_OBJECT_UNLOCK (bin);
3370 /* this function is called when there are no more async elements in the bin. We
3371 * post a state changed message and an ASYNC_DONE message.
3372 * This function is called with the OBJECT lock.
3375 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3376 gboolean flag_pending, GstClockTime running_time)
3378 GstState current, pending, target;
3379 GstStateChangeReturn old_ret;
3380 GstState old_state, old_next;
3381 gboolean toplevel, state_changed = FALSE;
3382 GstMessage *amessage = NULL;
3383 BinContinueData *cont = NULL;
3385 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3388 pending = GST_STATE_PENDING (bin);
3393 /* check if there is something to commit */
3394 if (pending == GST_STATE_VOID_PENDING)
3395 goto nothing_pending;
3397 old_ret = GST_STATE_RETURN (bin);
3398 GST_STATE_RETURN (bin) = ret;
3400 /* move to the next target state */
3401 target = GST_STATE_TARGET (bin);
3402 pending = GST_STATE_PENDING (bin) = target;
3404 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3406 old_state = GST_STATE (bin);
3407 /* this is the state we should go to next */
3408 old_next = GST_STATE_NEXT (bin);
3410 if (old_next != GST_STATE_PLAYING) {
3411 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3412 "committing state from %s to %s, old pending %s",
3413 gst_element_state_get_name (old_state),
3414 gst_element_state_get_name (old_next),
3415 gst_element_state_get_name (pending));
3417 /* update current state */
3418 current = GST_STATE (bin) = old_next;
3420 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3421 "setting state from %s to %s, pending %s",
3422 gst_element_state_get_name (old_state),
3423 gst_element_state_get_name (old_state),
3424 gst_element_state_get_name (pending));
3425 current = old_state;
3428 /* get our toplevel state */
3429 toplevel = BIN_IS_TOPLEVEL (bin);
3431 /* see if we reached the final state. If we are not toplevel, we also have to
3432 * stop here, the parent will continue our state. */
3433 if ((pending == current) || !toplevel) {
3434 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3435 "completed state change, pending VOID");
3437 /* mark VOID pending */
3438 pending = GST_STATE_VOID_PENDING;
3439 GST_STATE_PENDING (bin) = pending;
3440 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3442 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3443 "continue state change, pending %s",
3444 gst_element_state_get_name (pending));
3446 cont = g_slice_new (BinContinueData);
3448 /* cookie to detect concurrent state change */
3449 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3450 /* pending target state */
3451 cont->pending = pending;
3453 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3454 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3457 if (old_next != GST_STATE_PLAYING) {
3458 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3459 state_changed = TRUE;
3462 GST_OBJECT_UNLOCK (bin);
3464 if (state_changed) {
3465 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3469 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3470 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3471 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3474 GST_OBJECT_LOCK (bin);
3476 /* toplevel, start continue state */
3477 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3478 bin_push_state_continue (bin, cont);
3480 GST_DEBUG_OBJECT (bin, "state change complete");
3481 GST_STATE_BROADCAST (bin);
3487 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3492 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3493 /* if we were busy with a state change and we are requested to flag a
3494 * pending async done, we do so here */
3496 bin->priv->pending_async_done = TRUE;
3501 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3507 bin_do_eos (GstBin * bin)
3512 GST_OBJECT_LOCK (bin);
3513 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3514 * (or we're doing playing to playing and noone else will trigger posting
3515 * EOS for us) we forward the EOS message to the parent bin or application
3517 eos = GST_STATE (bin) == GST_STATE_PLAYING
3518 && (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING ||
3519 GST_STATE_PENDING (bin) == GST_STATE_PLAYING)
3520 && bin->priv->posted_playing && is_eos (bin, &seqnum);
3521 GST_OBJECT_UNLOCK (bin);
3524 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3526 GstMessage *tmessage;
3528 /* Clear out any further messages, and reset posted_eos so we can
3529 detect any new EOS that happens (eg, after a seek). Since all
3530 sinks have now posted an EOS, there will be no further EOS events
3531 seen unless there is a new logical EOS */
3532 GST_OBJECT_LOCK (bin);
3533 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3534 bin->priv->posted_eos = FALSE;
3535 GST_OBJECT_UNLOCK (bin);
3537 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3538 gst_message_set_seqnum (tmessage, seqnum);
3539 GST_DEBUG_OBJECT (bin,
3540 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3541 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3543 GST_LOG_OBJECT (bin, "Not forwarding EOS due to in progress state change, "
3544 " or already posted, or waiting for more EOS");
3549 bin_do_stream_start (GstBin * bin)
3552 gboolean stream_start;
3553 gboolean have_group_id = FALSE;
3556 GST_OBJECT_LOCK (bin);
3557 /* If all sinks are STREAM_START we forward the STREAM_START message
3558 * to the parent bin or application
3560 stream_start = is_stream_start (bin, &seqnum, &have_group_id, &group_id);
3561 GST_OBJECT_UNLOCK (bin);
3564 GstMessage *tmessage;
3566 GST_OBJECT_LOCK (bin);
3567 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3568 GST_OBJECT_UNLOCK (bin);
3570 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3571 gst_message_set_seqnum (tmessage, seqnum);
3573 gst_message_set_group_id (tmessage, group_id);
3575 GST_DEBUG_OBJECT (bin,
3576 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3578 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3582 /* must be called without the object lock as it posts messages */
3584 bin_do_message_forward (GstBin * bin, GstMessage * message)
3586 if (bin->priv->message_forward) {
3587 GstMessage *forwarded;
3589 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3590 GST_MESSAGE_TYPE_NAME (message));
3592 /* we need to convert these messages to element messages so that our parent
3593 * bin can easily ignore them and so that the application can easily
3594 * distinguish between the internally forwarded and the real messages. */
3595 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3596 gst_structure_new ("GstBinForwarded",
3597 "message", GST_TYPE_MESSAGE, message, NULL));
3599 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3604 gst_bin_update_context (GstBin * bin, GstContext * context)
3606 GST_OBJECT_LOCK (bin);
3607 gst_bin_update_context_unlocked (bin, context);
3608 GST_OBJECT_UNLOCK (bin);
3612 gst_bin_update_context_unlocked (GstBin * bin, GstContext * context)
3614 const gchar *context_type;
3615 GList *l, **contexts;
3617 contexts = &GST_ELEMENT_CAST (bin)->contexts;
3618 context_type = gst_context_get_context_type (context);
3620 GST_DEBUG_OBJECT (bin, "set context %p %" GST_PTR_FORMAT, context,
3621 gst_context_get_structure (context));
3622 for (l = *contexts; l; l = l->next) {
3623 GstContext *tmp = l->data;
3624 const gchar *tmp_type = gst_context_get_context_type (tmp);
3626 /* Always store newest context but never replace
3627 * a persistent one by a non-persistent one */
3628 if (strcmp (context_type, tmp_type) == 0 &&
3629 (gst_context_is_persistent (context) ||
3630 !gst_context_is_persistent (tmp))) {
3631 gst_context_replace ((GstContext **) & l->data, context);
3635 /* Not found? Add */
3637 *contexts = g_list_prepend (*contexts, gst_context_ref (context));
3641 /* handle child messages:
3643 * This method is called synchronously when a child posts a message on
3646 * GST_MESSAGE_EOS: This message is only posted by sinks
3647 * in the PLAYING state. If all sinks posted the EOS message, post
3650 * GST_MESSAGE_STATE_DIRTY: Deprecated
3652 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3653 * element posts segment_start twice, only the last message is kept.
3655 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3656 * with the segment_done message. If there are no more segment_start
3657 * messages, post segment_done message upwards.
3659 * GST_MESSAGE_DURATION_CHANGED: clear any cached durations.
3660 * Whenever someone performs a duration query on the bin, we store the
3661 * result so we can answer it quicker the next time. Any element that
3662 * changes its duration marks our cached values invalid.
3663 * This message is also posted upwards. This is currently disabled
3664 * because too many elements don't post DURATION_CHANGED messages when
3665 * the duration changes.
3667 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3668 * can no longer provide a clock. The default bin behaviour is to
3669 * check if the lost clock was the one provided by the bin. If so and
3670 * we are currently in the PLAYING state, we forward the message to
3672 * This message is also generated when we remove a clock provider from
3673 * a bin. If this message is received by the application, it should
3674 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3675 * and a new base_time distribution.
3677 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3678 * can provide a clock. This mostly happens when we add a new clock
3679 * provider to the bin. The default behaviour of the bin is to mark the
3680 * currently selected clock as dirty, which will perform a clock
3681 * recalculation the next time we are asked to provide a clock.
3682 * This message is never sent to the application but is forwarded to
3685 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3686 * the state of the element and the fact that the element will need a
3687 * new base_time. This message is not forwarded to the application.
3689 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3690 * element when it posted ASYNC_START. If all elements are done, post a
3691 * ASYNC_DONE message to the parent.
3693 * OTHER: post upwards.
3696 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3699 GstMessageType type;
3700 GstMessage *tmessage;
3703 src = GST_MESSAGE_SRC (message);
3704 type = GST_MESSAGE_TYPE (message);
3706 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3707 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3708 GST_MESSAGE_TYPE_NAME (message));
3711 case GST_MESSAGE_ERROR:
3713 GST_OBJECT_LOCK (bin);
3715 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3716 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3717 GST_STATE_BROADCAST (bin);
3718 GST_OBJECT_UNLOCK (bin);
3722 case GST_MESSAGE_EOS:
3725 /* collect all eos messages from the children */
3726 bin_do_message_forward (bin, message);
3727 GST_OBJECT_LOCK (bin);
3728 /* ref message for future use */
3729 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3730 GST_OBJECT_UNLOCK (bin);
3735 case GST_MESSAGE_STREAM_START:
3738 /* collect all stream_start messages from the children */
3739 GST_OBJECT_LOCK (bin);
3740 /* ref message for future use */
3741 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3742 GST_OBJECT_UNLOCK (bin);
3744 bin_do_stream_start (bin);
3747 case GST_MESSAGE_STATE_DIRTY:
3749 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3752 gst_message_unref (message);
3755 case GST_MESSAGE_SEGMENT_START:{
3756 gboolean post = FALSE;
3760 gst_message_parse_segment_start (message, &format, &position);
3761 seqnum = gst_message_get_seqnum (message);
3763 bin_do_message_forward (bin, message);
3765 GST_OBJECT_LOCK (bin);
3766 /* if this is the first segment-start, post to parent but not to the
3768 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3769 (GST_OBJECT_PARENT (bin) != NULL)) {
3772 /* replace any previous segment_start message from this source
3773 * with the new segment start message */
3774 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3775 GST_OBJECT_UNLOCK (bin);
3777 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3779 gst_message_set_seqnum (tmessage, seqnum);
3781 /* post segment start with initial format and position. */
3782 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3784 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3788 case GST_MESSAGE_SEGMENT_DONE:
3790 gboolean post = FALSE;
3794 gst_message_parse_segment_done (message, &format, &position);
3795 seqnum = gst_message_get_seqnum (message);
3797 bin_do_message_forward (bin, message);
3799 GST_OBJECT_LOCK (bin);
3800 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3801 /* if there are no more segment_start messages, everybody posted
3802 * a segment_done and we can post one on the bus. */
3804 /* we don't care who still has a pending segment start */
3805 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3808 /* remove all old segment_done messages */
3809 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3811 GST_OBJECT_UNLOCK (bin);
3813 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3815 gst_message_set_seqnum (tmessage, seqnum);
3817 /* post segment done with latest format and position. */
3818 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3820 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3824 case GST_MESSAGE_DURATION_CHANGED:
3826 /* FIXME: remove all cached durations, next time somebody asks
3827 * for duration, we will recalculate. */
3829 GST_OBJECT_LOCK (bin);
3830 bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION_CHANGED);
3831 GST_OBJECT_UNLOCK (bin);
3835 case GST_MESSAGE_CLOCK_LOST:
3837 GstClock **provided_clock_p;
3838 GstElement **clock_provider_p;
3839 gboolean playing, toplevel, provided, forward;
3842 gst_message_parse_clock_lost (message, &clock);
3844 GST_OBJECT_LOCK (bin);
3845 bin->clock_dirty = TRUE;
3846 /* if we lost the clock that we provided, post to parent but
3847 * only if we are not a top-level bin or PLAYING.
3848 * The reason for this is that applications should be able
3849 * to PAUSE/PLAY if they receive this message without worrying
3850 * about the state of the pipeline. */
3851 provided = (clock == bin->provided_clock);
3852 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3853 toplevel = GST_OBJECT_PARENT (bin) == NULL;
3854 forward = provided && (playing || !toplevel);
3856 GST_DEBUG_OBJECT (bin,
3857 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3858 bin->provided_clock, bin->clock_provider);
3859 provided_clock_p = &bin->provided_clock;
3860 clock_provider_p = &bin->clock_provider;
3861 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3862 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3864 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3865 provided, playing, forward);
3866 GST_OBJECT_UNLOCK (bin);
3872 gst_message_unref (message);
3875 case GST_MESSAGE_CLOCK_PROVIDE:
3879 GST_OBJECT_LOCK (bin);
3880 bin->clock_dirty = TRUE;
3881 /* a new clock is available, post to parent but not
3882 * to the application */
3883 forward = GST_OBJECT_PARENT (bin) != NULL;
3884 GST_OBJECT_UNLOCK (bin);
3890 gst_message_unref (message);
3893 case GST_MESSAGE_ASYNC_START:
3897 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3898 src ? GST_OBJECT_NAME (src) : "(NULL)");
3900 bin_do_message_forward (bin, message);
3902 GST_OBJECT_LOCK (bin);
3903 /* we ignore the message if we are going to <= READY */
3904 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3905 goto ignore_start_message;
3907 /* takes ownership of the message */
3908 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3910 bin_handle_async_start (bin);
3911 GST_OBJECT_UNLOCK (bin);
3914 ignore_start_message:
3916 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3917 gst_element_state_get_name (target));
3918 GST_OBJECT_UNLOCK (bin);
3919 gst_message_unref (message);
3923 case GST_MESSAGE_ASYNC_DONE:
3925 GstClockTime running_time;
3928 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3929 src ? GST_OBJECT_NAME (src) : "(NULL)");
3931 gst_message_parse_async_done (message, &running_time);
3933 bin_do_message_forward (bin, message);
3935 GST_OBJECT_LOCK (bin);
3936 /* ignore messages if we are shutting down */
3937 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3938 goto ignore_done_message;
3940 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3941 /* if there are no more ASYNC_START messages, everybody posted
3942 * a ASYNC_DONE and we can post one on the bus. When checking, we
3943 * don't care who still has a pending ASYNC_START */
3944 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3945 /* nothing found, remove all old ASYNC_DONE messages */
3946 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3948 GST_DEBUG_OBJECT (bin, "async elements commited");
3949 /* when we get an async done message when a state change was busy, we
3950 * need to set the pending_done flag so that at the end of the state
3951 * change we can see if we need to verify pending async elements, hence
3952 * the TRUE argument here. */
3953 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3956 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3958 GST_OBJECT_UNLOCK (bin);
3961 ignore_done_message:
3963 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3964 gst_element_state_get_name (target));
3965 GST_OBJECT_UNLOCK (bin);
3966 gst_message_unref (message);
3970 case GST_MESSAGE_STRUCTURE_CHANGE:
3974 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3976 GST_OBJECT_LOCK (bin);
3978 /* while the pad is busy, avoid following it when doing state changes.
3979 * Don't update the cookie yet, we will do that after the structure
3980 * change finished and we are ready to inspect the new updated
3982 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3985 /* a pad link/unlink ended, signal the state change iterator that we
3986 * need to resync by updating the structure_cookie. */
3987 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3988 GST_MESSAGE_STRUCTURE_CHANGE);
3989 if (!GST_BIN_IS_NO_RESYNC (bin))
3990 bin->priv->structure_cookie++;
3992 GST_OBJECT_UNLOCK (bin);
3995 gst_message_unref (message);
3999 case GST_MESSAGE_NEED_CONTEXT:{
4000 const gchar *context_type;
4001 GList *l, *contexts;
4003 gst_message_parse_context_type (message, &context_type);
4004 GST_OBJECT_LOCK (bin);
4005 contexts = GST_ELEMENT_CAST (bin)->contexts;
4006 GST_LOG_OBJECT (bin, "got need-context message type: %s", context_type);
4007 for (l = contexts; l; l = l->next) {
4008 GstContext *tmp = l->data;
4009 const gchar *tmp_type = gst_context_get_context_type (tmp);
4011 if (strcmp (context_type, tmp_type) == 0) {
4012 gst_element_set_context (GST_ELEMENT (src), l->data);
4016 GST_OBJECT_UNLOCK (bin);
4018 /* Forward if we couldn't answer the message */
4022 gst_message_unref (message);
4027 case GST_MESSAGE_HAVE_CONTEXT:{
4028 GstContext *context;
4030 gst_message_parse_have_context (message, &context);
4031 gst_bin_update_context (bin, context);
4032 gst_context_unref (context);
4044 /* Send all other messages upward */
4045 GST_DEBUG_OBJECT (bin, "posting message upward");
4046 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
4051 /* generic struct passed to all query fold methods */
4060 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
4061 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
4063 /* for duration/position we collect all durations/positions and take
4064 * the MAX of all valid results */
4066 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
4074 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4076 gboolean res = FALSE;
4077 GstObject *item = g_value_get_object (vitem);
4078 if (GST_IS_PAD (item))
4079 res = gst_pad_query (GST_PAD (item), fold->query);
4081 res = gst_element_query (GST_ELEMENT (item), fold->query);
4086 g_value_set_boolean (ret, TRUE);
4088 gst_query_parse_duration (fold->query, NULL, &duration);
4090 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
4092 if (duration == -1) {
4093 /* duration query succeeded, but duration is unknown */
4098 if (duration > fold->max)
4099 fold->max = duration;
4106 bin_query_duration_done (GstBin * bin, QueryFold * fold)
4110 gst_query_parse_duration (fold->query, &format, NULL);
4111 /* store max in query result */
4112 gst_query_set_duration (fold->query, format, fold->max);
4114 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
4116 /* FIXME: re-implement duration caching */
4119 GST_OBJECT_LOCK (bin);
4120 bin->messages = g_list_prepend (bin->messages,
4121 gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
4122 GST_OBJECT_UNLOCK (bin);
4127 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4129 gboolean res = FALSE;
4130 GstObject *item = g_value_get_object (vitem);
4131 if (GST_IS_PAD (item))
4132 res = gst_pad_query (GST_PAD (item), fold->query);
4134 res = gst_element_query (GST_ELEMENT (item), fold->query);
4139 g_value_set_boolean (ret, TRUE);
4141 gst_query_parse_position (fold->query, NULL, &position);
4143 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
4145 if (position > fold->max)
4146 fold->max = position;
4153 bin_query_position_done (GstBin * bin, QueryFold * fold)
4157 gst_query_parse_position (fold->query, &format, NULL);
4158 /* store max in query result */
4159 gst_query_set_position (fold->query, format, fold->max);
4161 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
4165 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4167 gboolean res = FALSE;
4168 GstObject *item = g_value_get_object (vitem);
4169 if (GST_IS_PAD (item))
4170 res = gst_pad_query (GST_PAD (item), fold->query);
4172 res = gst_element_query (GST_ELEMENT (item), fold->query);
4174 GstClockTime min, max;
4177 gst_query_parse_latency (fold->query, &live, &min, &max);
4179 GST_DEBUG_OBJECT (item,
4180 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
4181 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
4183 /* for the combined latency we collect the MAX of all min latencies and
4184 * the MIN of all max latencies */
4186 if (min > fold->min)
4188 if (fold->max == -1)
4190 else if (max < fold->max)
4196 g_value_set_boolean (ret, FALSE);
4197 GST_DEBUG_OBJECT (item, "failed query");
4204 bin_query_latency_done (GstBin * bin, QueryFold * fold)
4206 /* store max in query result */
4207 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
4209 GST_DEBUG_OBJECT (bin,
4210 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
4211 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
4215 /* generic fold, return first valid result */
4217 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4219 gboolean res = FALSE;
4220 GstObject *item = g_value_get_object (vitem);
4221 if (GST_IS_PAD (item))
4222 res = gst_pad_query (GST_PAD (item), fold->query);
4224 res = gst_element_query (GST_ELEMENT (item), fold->query);
4226 g_value_set_boolean (ret, TRUE);
4227 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
4230 /* and stop as soon as we have a valid result */
4234 /* Perform a query iteration for the given bin. The query is stored in
4235 * QueryFold and iter should be either a GstPad iterator or a
4236 * GstElement iterator. */
4238 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
4239 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
4240 QueryFold * fold_data, gboolean default_return)
4242 gboolean res = default_return;
4244 /* set the result of the query to FALSE initially */
4245 g_value_init (&ret, G_TYPE_BOOLEAN);
4246 g_value_set_boolean (&ret, res);
4249 GstIteratorResult ires;
4251 ires = gst_iterator_fold (iter, fold_func, &ret, fold_data);
4254 case GST_ITERATOR_RESYNC:
4255 gst_iterator_resync (iter);
4257 fold_init (bin, fold_data);
4258 g_value_set_boolean (&ret, res);
4260 case GST_ITERATOR_OK:
4261 case GST_ITERATOR_DONE:
4262 res = g_value_get_boolean (&ret);
4263 if (fold_done != NULL && res)
4264 fold_done (bin, fold_data);
4276 gst_bin_query (GstElement * element, GstQuery * query)
4278 GstBin *bin = GST_BIN_CAST (element);
4280 gboolean default_return = FALSE;
4281 gboolean res = FALSE;
4282 gboolean src_pads_query_result = FALSE;
4283 GstIteratorFoldFunction fold_func;
4284 QueryInitFunction fold_init = NULL;
4285 QueryDoneFunction fold_done = NULL;
4286 QueryFold fold_data;
4288 switch (GST_QUERY_TYPE (query)) {
4289 case GST_QUERY_DURATION:
4291 /* FIXME: implement duration caching in GstBin again */
4296 gst_query_parse_duration (query, &qformat, NULL);
4298 /* find cached duration query */
4299 GST_OBJECT_LOCK (bin);
4300 for (cached = bin->messages; cached; cached = g_list_next (cached)) {
4301 GstMessage *message = (GstMessage *) cached->data;
4303 if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION_CHANGED &&
4304 GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
4308 gst_message_parse_duration (message, &format, &duration);
4310 /* if cached same format, copy duration in query result */
4311 if (format == qformat) {
4312 GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
4314 GST_OBJECT_UNLOCK (bin);
4316 gst_query_set_duration (query, qformat, duration);
4322 GST_OBJECT_UNLOCK (bin);
4324 #ifndef GST_DISABLE_GST_DEBUG
4326 /* Quieten this particularly annoying FIXME a bit: */
4327 static gboolean printed_fixme = FALSE;
4328 if (!printed_fixme) {
4329 GST_FIXME ("implement duration caching in GstBin again");
4330 printed_fixme = TRUE;
4336 /* no cached value found, iterate and collect durations */
4337 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
4338 fold_init = bin_query_min_max_init;
4339 fold_done = bin_query_duration_done;
4342 case GST_QUERY_POSITION:
4344 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
4345 fold_init = bin_query_min_max_init;
4346 fold_done = bin_query_position_done;
4349 case GST_QUERY_LATENCY:
4351 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
4352 fold_init = bin_query_min_max_init;
4353 fold_done = bin_query_latency_done;
4354 default_return = TRUE;
4358 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
4362 fold_data.query = query;
4364 iter = gst_bin_iterate_sinks (bin);
4365 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
4366 query, GST_QUERY_TYPE_NAME (query));
4369 fold_init (bin, &fold_data);
4372 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, &fold_data,
4374 gst_iterator_free (iter);
4377 /* Query the source pads of the element */
4378 iter = gst_element_iterate_src_pads (element);
4379 src_pads_query_result =
4380 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
4381 &fold_data, default_return);
4382 gst_iterator_free (iter);
4384 if (src_pads_query_result)
4388 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
4394 set_context (const GValue * item, gpointer user_data)
4396 GstElement *element = g_value_get_object (item);
4398 gst_element_set_context (element, user_data);
4402 gst_bin_set_context (GstElement * element, GstContext * context)
4405 GstIterator *children;
4407 g_return_if_fail (GST_IS_BIN (element));
4409 bin = GST_BIN (element);
4411 GST_ELEMENT_CLASS (parent_class)->set_context (element, context);
4413 children = gst_bin_iterate_elements (bin);
4414 while (gst_iterator_foreach (children, set_context,
4415 context) == GST_ITERATOR_RESYNC)
4416 gst_iterator_resync (children);
4417 gst_iterator_free (children);
4421 compare_name (const GValue * velement, const gchar * name)
4424 GstElement *element = g_value_get_object (velement);
4426 GST_OBJECT_LOCK (element);
4427 eq = strcmp (GST_ELEMENT_NAME (element), name);
4428 GST_OBJECT_UNLOCK (element);
4434 * gst_bin_get_by_name:
4436 * @name: the element name to search for
4438 * Gets the element with the given name from a bin. This
4439 * function recurses into child bins.
4441 * Returns %NULL if no element with the given name is found in the bin.
4443 * MT safe. Caller owns returned reference.
4445 * Returns: (transfer full) (nullable): the #GstElement with the given
4449 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4451 GstIterator *children;
4452 GValue result = { 0, };
4453 GstElement *element;
4456 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4458 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4459 GST_ELEMENT_NAME (bin), name);
4461 children = gst_bin_iterate_recurse (bin);
4462 found = gst_iterator_find_custom (children,
4463 (GCompareFunc) compare_name, &result, (gpointer) name);
4464 gst_iterator_free (children);
4467 element = g_value_dup_object (&result);
4468 g_value_unset (&result);
4477 * gst_bin_get_by_name_recurse_up:
4479 * @name: the element name to search for
4481 * Gets the element with the given name from this bin. If the
4482 * element is not found, a recursion is performed on the parent bin.
4485 * - no element with the given name is found in the bin
4487 * MT safe. Caller owns returned reference.
4489 * Returns: (transfer full) (nullable): the #GstElement with the given
4493 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4497 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4498 g_return_val_if_fail (name != NULL, NULL);
4500 result = gst_bin_get_by_name (bin, name);
4505 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4507 if (GST_IS_BIN (parent)) {
4508 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4510 gst_object_unref (parent);
4518 compare_interface (const GValue * velement, GValue * interface)
4520 GstElement *element = g_value_get_object (velement);
4521 GType interface_type = (GType) g_value_get_pointer (interface);
4524 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4533 * gst_bin_get_by_interface:
4535 * @iface: the #GType of an interface
4537 * Looks for an element inside the bin that implements the given
4538 * interface. If such an element is found, it returns the element.
4539 * You can cast this element to the given interface afterwards. If you want
4540 * all elements that implement the interface, use
4541 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4543 * MT safe. Caller owns returned reference.
4545 * Returns: (transfer full): A #GstElement inside the bin implementing the interface
4548 gst_bin_get_by_interface (GstBin * bin, GType iface)
4550 GstIterator *children;
4551 GValue result = { 0, };
4552 GstElement *element;
4554 GValue viface = { 0, };
4556 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4557 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4559 g_value_init (&viface, G_TYPE_POINTER);
4560 g_value_set_pointer (&viface, (gpointer) iface);
4562 children = gst_bin_iterate_recurse (bin);
4563 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4565 gst_iterator_free (children);
4568 element = g_value_dup_object (&result);
4569 g_value_unset (&result);
4573 g_value_unset (&viface);
4579 * gst_bin_iterate_all_by_interface:
4581 * @iface: the #GType of an interface
4583 * Looks for all elements inside the bin that implements the given
4584 * interface. You can safely cast all returned elements to the given interface.
4585 * The function recurses inside child bins. The iterator will yield a series
4586 * of #GstElement that should be unreffed after use.
4588 * MT safe. Caller owns returned value.
4590 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
4591 * for all elements in the bin implementing the given interface,
4595 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4597 GstIterator *children;
4598 GstIterator *result;
4599 GValue viface = { 0, };
4601 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4602 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4604 g_value_init (&viface, G_TYPE_POINTER);
4605 g_value_set_pointer (&viface, (gpointer) iface);
4607 children = gst_bin_iterate_recurse (bin);
4608 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4611 g_value_unset (&viface);