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.
28 * @short_description: Base class and element that can contain other elements
30 * #GstBin is an element that can contain other #GstElement, allowing them to be
32 * Pads from the child elements can be ghosted to the bin, see #GstGhostPad.
33 * This makes the bin look like any other elements and enables creation of
34 * higher-level abstraction elements.
36 * A new #GstBin is created with gst_bin_new(). Use a #GstPipeline instead if you
37 * want to create a toplevel bin because a normal bin doesn't have a bus or
38 * handle clock distribution of its own.
40 * After the bin has been created you will typically add elements to it with
41 * gst_bin_add(). You can remove elements with gst_bin_remove().
43 * An element can be retrieved from a bin with gst_bin_get_by_name(), using the
44 * elements name. gst_bin_get_by_name_recurse_up() is mainly used for internal
45 * purposes and will query the parent bins when the element is not found in the
48 * An iterator of elements in a bin can be retrieved with
49 * gst_bin_iterate_elements(). Various other iterators exist to retrieve the
52 * gst_object_unref() is used to drop your reference to the bin.
54 * The #GstBin::element-added signal is fired whenever a new element is added to
55 * the bin. Likewise the #GstBin::element-removed signal is fired whenever an
56 * element is removed from the bin.
58 * <refsect2><title>Notes</title>
60 * A #GstBin internally intercepts every #GstMessage posted by its children and
61 * implements the following default behaviour for each of them:
64 * <term>GST_MESSAGE_EOS</term>
65 * <listitem><para>This message is only posted by sinks in the PLAYING
66 * state. If all sinks posted the EOS message, this bin will post and EOS
67 * message upwards.</para></listitem>
70 * <term>GST_MESSAGE_SEGMENT_START</term>
71 * <listitem><para>just collected and never forwarded upwards.
72 * The messages are used to decide when all elements have completed playback
73 * of their segment.</para></listitem>
76 * <term>GST_MESSAGE_SEGMENT_DONE</term>
77 * <listitem><para> Is posted by #GstBin when all elements that posted
78 * a SEGMENT_START have posted a SEGMENT_DONE.</para></listitem>
81 * <term>GST_MESSAGE_DURATION_CHANGED</term>
82 * <listitem><para> Is posted by an element that detected a change
83 * in the stream duration. The default bin behaviour is to clear any
84 * cached duration values so that the next duration query will perform
85 * a full duration recalculation. The duration change is posted to the
86 * application so that it can refetch the new duration with a duration
87 * query. Note that these messages can be posted before the bin is
88 * prerolled, in which case the duration query might fail.
92 * <term>GST_MESSAGE_CLOCK_LOST</term>
93 * <listitem><para> This message is posted by an element when it
94 * can no longer provide a clock. The default bin behaviour is to
95 * check if the lost clock was the one provided by the bin. If so and
96 * the bin is currently in the PLAYING state, the message is forwarded to
98 * This message is also generated when a clock provider is removed from
99 * the bin. If this message is received by the application, it should
100 * PAUSE the pipeline and set it back to PLAYING to force a new clock
105 * <term>GST_MESSAGE_CLOCK_PROVIDE</term>
106 * <listitem><para> This message is generated when an element
107 * can provide a clock. This mostly happens when a new clock
108 * provider is added to the bin. The default behaviour of the bin is to
109 * mark the currently selected clock as dirty, which will perform a clock
110 * recalculation the next time the bin is asked to provide a clock.
111 * This message is never sent tot the application but is forwarded to
112 * the parent of the bin.
116 * <term>OTHERS</term>
117 * <listitem><para> posted upwards.</para></listitem>
122 * A #GstBin implements the following default behaviour for answering to a
126 * <term>GST_QUERY_DURATION</term>
127 * <listitem><para>If the query has been asked before with the same format
128 * and the bin is a toplevel bin (ie. has no parent),
129 * use the cached previous value. If no previous value was cached, the
130 * query is sent to all sink elements in the bin and the MAXIMUM of all
131 * values is returned. If the bin is a toplevel bin the value is cached.
132 * If no sinks are available in the bin, the query fails.
136 * <term>GST_QUERY_POSITION</term>
137 * <listitem><para>The query is sent to all sink elements in the bin and the
138 * MAXIMUM of all values is returned. If no sinks are available in the bin,
143 * <term>OTHERS</term>
144 * <listitem><para>the query is forwarded to all sink elements, the result
145 * of the first sink that answers the query successfully is returned. If no
146 * sink is in the bin, the query fails.</para></listitem>
150 * A #GstBin will by default forward any event sent to it to all sink elements.
151 * If all the sinks return TRUE, the bin will also return TRUE, else FALSE is
152 * returned. If no sinks are in the bin, the event handler will return TRUE.
157 * Last reviewed on 2012-03-28 (0.11.3)
160 #include "gst_private.h"
162 #include "gstevent.h"
165 #include "gsterror.h"
167 #include "gstutils.h"
168 #include "gstchildproxy.h"
170 GST_DEBUG_CATEGORY_STATIC (bin_debug);
171 #define GST_CAT_DEFAULT bin_debug
173 /* a bin is toplevel if it has no parent or when it is configured to behave like
175 #define BIN_IS_TOPLEVEL(bin) ((GST_OBJECT_PARENT (bin) == NULL) || bin->priv->asynchandling)
177 #define GST_BIN_GET_PRIVATE(obj) \
178 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BIN, GstBinPrivate))
180 struct _GstBinPrivate
182 gboolean asynchandling;
183 /* if we get an ASYNC_DONE message from ourselves, this means that the
184 * subclass will simulate ASYNC behaviour without having ASYNC children. When
185 * such an ASYNC_DONE message is posted while we are doing a state change, we
186 * have to process the message after finishing the state change even when no
187 * child returned GST_STATE_CHANGE_ASYNC. */
188 gboolean pending_async_done;
190 guint32 structure_cookie;
197 /* forward messages from our children */
198 gboolean message_forward;
210 static void gst_bin_dispose (GObject * object);
212 static void gst_bin_set_property (GObject * object, guint prop_id,
213 const GValue * value, GParamSpec * pspec);
214 static void gst_bin_get_property (GObject * object, guint prop_id,
215 GValue * value, GParamSpec * pspec);
217 static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
218 GstStateChange transition);
219 static void gst_bin_state_changed (GstElement * element, GstState oldstate,
220 GstState newstate, GstState pending);
221 static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
222 GstState * state, GstState * pending, GstClockTime timeout);
223 static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
224 gboolean flag_pending, GstClockTime running_time);
225 static void bin_handle_async_start (GstBin * bin);
226 static void bin_push_state_continue (BinContinueData * data);
227 static void bin_do_eos (GstBin * bin);
229 static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
230 static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
233 static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
234 static GstIndex *gst_bin_get_index_func (GstElement * element);
237 static GstClock *gst_bin_provide_clock_func (GstElement * element);
238 static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
240 static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
241 static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
242 static GstBusSyncReply bin_bus_handler (GstBus * bus,
243 GstMessage * message, GstBin * bin);
244 static gboolean gst_bin_query (GstElement * element, GstQuery * query);
245 static void gst_bin_set_context (GstElement * element, GstContext * context);
247 static gboolean gst_bin_do_latency_func (GstBin * bin);
249 static void bin_remove_messages (GstBin * bin, GstObject * src,
250 GstMessageType types);
251 static void gst_bin_continue_func (BinContinueData * data);
252 static gint bin_element_is_sink (GstElement * child, GstBin * bin);
253 static gint bin_element_is_src (GstElement * child, GstBin * bin);
255 static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
257 /* Bin signals and properties */
266 #define DEFAULT_ASYNC_HANDLING FALSE
267 #define DEFAULT_MESSAGE_FORWARD FALSE
273 PROP_MESSAGE_FORWARD,
277 static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
279 static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
283 static const GInterfaceInfo iface_info = { \
284 gst_bin_child_proxy_init, \
288 g_type_add_interface_static (g_define_type_id, GST_TYPE_CHILD_PROXY, &iface_info); \
290 GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
291 "debugging info for the 'bin' container element"); \
295 #define gst_bin_parent_class parent_class
296 G_DEFINE_TYPE_WITH_CODE (GstBin, gst_bin, GST_TYPE_ELEMENT, _do_init);
299 gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
305 bin = GST_BIN_CAST (child_proxy);
307 GST_OBJECT_LOCK (bin);
308 if ((res = g_list_nth_data (bin->children, index)))
309 gst_object_ref (res);
310 GST_OBJECT_UNLOCK (bin);
312 return (GObject *) res;
316 gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
321 bin = GST_BIN_CAST (child_proxy);
323 GST_OBJECT_LOCK (bin);
324 num = bin->numchildren;
325 GST_OBJECT_UNLOCK (bin);
331 gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
333 GstChildProxyInterface *iface = g_iface;
335 iface->get_children_count = gst_bin_child_proxy_get_children_count;
336 iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
340 _gst_boolean_accumulator (GSignalInvocationHint * ihint,
341 GValue * return_accu, const GValue * handler_return, gpointer dummy)
345 myboolean = g_value_get_boolean (handler_return);
346 if (!(ihint->run_type & G_SIGNAL_RUN_CLEANUP))
347 g_value_set_boolean (return_accu, myboolean);
349 GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
356 gst_bin_class_init (GstBinClass * klass)
358 GObjectClass *gobject_class;
359 GstElementClass *gstelement_class;
362 gobject_class = (GObjectClass *) klass;
363 gstelement_class = (GstElementClass *) klass;
365 g_type_class_add_private (klass, sizeof (GstBinPrivate));
367 gobject_class->set_property = gst_bin_set_property;
368 gobject_class->get_property = gst_bin_get_property;
371 * GstBin:async-handling:
373 * If set to #TRUE, the bin will handle asynchronous state changes.
374 * This should be used only if the bin subclass is modifying the state
375 * of its children on its own.
377 g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
378 g_param_spec_boolean ("async-handling", "Async Handling",
379 "The bin will handle Asynchronous state changes",
380 DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
383 * GstBin::element-added:
385 * @element: the #GstElement that was added to the bin
387 * Will be emitted after the element was added to the bin.
389 gst_bin_signals[ELEMENT_ADDED] =
390 g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
391 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
392 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
394 * GstBin::element-removed:
396 * @element: the #GstElement that was removed from the bin
398 * Will be emitted after the element was removed from the bin.
400 gst_bin_signals[ELEMENT_REMOVED] =
401 g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
402 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
403 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
405 * GstBin::do-latency:
408 * Will be emitted when the bin needs to perform latency calculations. This
409 * signal is only emited for toplevel bins or when async-handling is
412 * Only one signal handler is invoked. If no signals are connected, the
413 * default handler is invoked, which will query and distribute the lowest
414 * possible latency to all sinks.
416 * Connect to this signal if the default latency calculations are not
417 * sufficient, like when you need different latencies for different sinks in
420 gst_bin_signals[DO_LATENCY] =
421 g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
422 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
423 _gst_boolean_accumulator, NULL, g_cclosure_marshal_generic,
424 G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
427 * GstBin:message-forward:
429 * Forward all children messages, even those that would normally be filtered by
430 * the bin. This can be interesting when one wants to be notified of the EOS
431 * state of individual elements, for example.
433 * The messages are converted to an ELEMENT message with the bin as the
434 * source. The structure of the message is named 'GstBinForwarded' and contains
435 * a field named 'message' of type GST_TYPE_MESSAGE that contains the original
438 g_object_class_install_property (gobject_class, PROP_MESSAGE_FORWARD,
439 g_param_spec_boolean ("message-forward", "Message Forward",
440 "Forwards all children messages",
441 DEFAULT_MESSAGE_FORWARD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
443 gobject_class->dispose = gst_bin_dispose;
445 gst_element_class_set_static_metadata (gstelement_class, "Generic bin",
447 "Simple container object",
448 "Erik Walthinsen <omega@cse.ogi.edu>,"
449 "Wim Taymans <wim.taymans@gmail.com>");
451 gstelement_class->change_state =
452 GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
453 gstelement_class->state_changed = GST_DEBUG_FUNCPTR (gst_bin_state_changed);
454 gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
456 gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
457 gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
459 gstelement_class->provide_clock =
460 GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
461 gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
463 gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
464 gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
465 gstelement_class->set_context = GST_DEBUG_FUNCPTR (gst_bin_set_context);
467 klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
468 klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
469 klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
471 klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
473 GST_DEBUG ("creating bin thread pool");
476 g_thread_pool_new ((GFunc) gst_bin_continue_func, NULL, -1, FALSE, &err);
478 g_critical ("could alloc threadpool %s", err->message);
483 gst_bin_init (GstBin * bin)
487 bin->numchildren = 0;
488 bin->children = NULL;
489 bin->children_cookie = 0;
490 bin->messages = NULL;
491 bin->provided_clock = NULL;
492 bin->clock_dirty = FALSE;
494 /* Set up a bus for listening to child elements */
495 bus = g_object_new (GST_TYPE_BUS, "enable-async", FALSE, NULL);
496 bin->child_bus = bus;
497 GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
499 gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin,
502 bin->priv = GST_BIN_GET_PRIVATE (bin);
503 bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
504 bin->priv->structure_cookie = 0;
505 bin->priv->message_forward = DEFAULT_MESSAGE_FORWARD;
509 gst_bin_dispose (GObject * object)
511 GstBin *bin = GST_BIN_CAST (object);
512 GstBus **child_bus_p = &bin->child_bus;
513 GstClock **provided_clock_p = &bin->provided_clock;
514 GstElement **clock_provider_p = &bin->clock_provider;
516 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "dispose");
518 GST_OBJECT_LOCK (object);
519 gst_object_replace ((GstObject **) child_bus_p, NULL);
520 gst_object_replace ((GstObject **) provided_clock_p, NULL);
521 gst_object_replace ((GstObject **) clock_provider_p, NULL);
522 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
523 GST_OBJECT_UNLOCK (object);
525 while (bin->children) {
526 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
528 if (G_UNLIKELY (bin->children != NULL)) {
529 g_critical ("could not remove elements from bin '%s'",
530 GST_STR_NULL (GST_OBJECT_NAME (object)));
533 G_OBJECT_CLASS (parent_class)->dispose (object);
538 * @name: the name of the new bin
540 * Creates a new bin with the given name.
542 * Returns: (transfer floating): a new #GstBin
545 gst_bin_new (const gchar * name)
547 return gst_element_factory_make ("bin", name);
551 gst_bin_set_property (GObject * object, guint prop_id,
552 const GValue * value, GParamSpec * pspec)
556 gstbin = GST_BIN_CAST (object);
559 case PROP_ASYNC_HANDLING:
560 GST_OBJECT_LOCK (gstbin);
561 gstbin->priv->asynchandling = g_value_get_boolean (value);
562 GST_OBJECT_UNLOCK (gstbin);
564 case PROP_MESSAGE_FORWARD:
565 GST_OBJECT_LOCK (gstbin);
566 gstbin->priv->message_forward = g_value_get_boolean (value);
567 GST_OBJECT_UNLOCK (gstbin);
570 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
576 gst_bin_get_property (GObject * object, guint prop_id,
577 GValue * value, GParamSpec * pspec)
581 gstbin = GST_BIN_CAST (object);
584 case PROP_ASYNC_HANDLING:
585 GST_OBJECT_LOCK (gstbin);
586 g_value_set_boolean (value, gstbin->priv->asynchandling);
587 GST_OBJECT_UNLOCK (gstbin);
589 case PROP_MESSAGE_FORWARD:
590 GST_OBJECT_LOCK (gstbin);
591 g_value_set_boolean (value, gstbin->priv->message_forward);
592 GST_OBJECT_UNLOCK (gstbin);
595 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
601 /* return the cached index */
603 gst_bin_get_index_func (GstElement * element)
608 bin = GST_BIN_CAST (element);
610 GST_OBJECT_LOCK (bin);
611 if ((result = bin->priv->index))
612 gst_object_ref (result);
613 GST_OBJECT_UNLOCK (bin);
618 /* set the index on all elements in this bin
623 gst_bin_set_index_func (GstElement * element, GstIndex * index)
629 GValue data = { 0, };
631 bin = GST_BIN_CAST (element);
633 GST_OBJECT_LOCK (bin);
634 old = bin->priv->index;
635 if (G_UNLIKELY (old == index))
638 gst_object_ref (index);
639 bin->priv->index = index;
640 GST_OBJECT_UNLOCK (bin);
643 gst_object_unref (old);
645 it = gst_bin_iterate_elements (bin);
647 /* set the index on all elements in the bin */
650 switch (gst_iterator_next (it, &data)) {
651 case GST_ITERATOR_OK:
653 GstElement *child = g_value_get_object (&data);
655 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
656 GST_ELEMENT_NAME (child));
657 gst_element_set_index (child, index);
659 g_value_reset (&data);
662 case GST_ITERATOR_RESYNC:
663 GST_DEBUG_OBJECT (bin, "iterator doing resync");
664 gst_iterator_resync (it);
667 case GST_ITERATOR_DONE:
668 GST_DEBUG_OBJECT (bin, "iterator done");
673 g_value_unset (&data);
674 gst_iterator_free (it);
679 GST_DEBUG_OBJECT (bin, "index was already set");
680 GST_OBJECT_UNLOCK (bin);
686 /* set the clock on all elements in this bin
691 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
697 GValue data = { 0, };
699 bin = GST_BIN_CAST (element);
701 it = gst_bin_iterate_elements (bin);
705 switch (gst_iterator_next (it, &data)) {
706 case GST_ITERATOR_OK:
708 GstElement *child = g_value_get_object (&data);
710 res &= gst_element_set_clock (child, clock);
712 g_value_reset (&data);
715 case GST_ITERATOR_RESYNC:
716 GST_DEBUG_OBJECT (bin, "iterator doing resync");
717 gst_iterator_resync (it);
721 case GST_ITERATOR_DONE:
722 GST_DEBUG_OBJECT (bin, "iterator done");
727 g_value_unset (&data);
728 gst_iterator_free (it);
731 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
736 /* get the clock for this bin by asking all of the children in this bin
738 * The ref of the returned clock in increased so unref after usage.
740 * We loop the elements in state order and pick the last clock we can
741 * get. This makes sure we get a clock from the source.
746 gst_bin_provide_clock_func (GstElement * element)
748 GstClock *result = NULL;
749 GstElement *provider = NULL;
754 GstClock **provided_clock_p;
755 GstElement **clock_provider_p;
757 bin = GST_BIN_CAST (element);
759 GST_OBJECT_LOCK (bin);
760 if (!bin->clock_dirty)
763 GST_DEBUG_OBJECT (bin, "finding new clock");
765 it = gst_bin_sort_iterator_new (bin);
766 GST_OBJECT_UNLOCK (bin);
770 switch (gst_iterator_next (it, &val)) {
771 case GST_ITERATOR_OK:
773 GstElement *child = g_value_get_object (&val);
776 clock = gst_element_provide_clock (child);
778 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
779 clock, GST_ELEMENT_NAME (child));
781 gst_object_unref (result);
782 gst_object_unref (provider);
785 provider = gst_object_ref (child);
788 g_value_reset (&val);
791 case GST_ITERATOR_RESYNC:
792 gst_iterator_resync (it);
795 case GST_ITERATOR_DONE:
800 g_value_unset (&val);
801 gst_iterator_free (it);
803 GST_OBJECT_LOCK (bin);
804 if (!bin->clock_dirty) {
806 gst_object_unref (provider);
808 gst_object_unref (result);
814 provided_clock_p = &bin->provided_clock;
815 clock_provider_p = &bin->clock_provider;
816 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
817 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
818 bin->clock_dirty = FALSE;
819 GST_DEBUG_OBJECT (bin,
820 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
822 /* Provider is not being returned to caller, just the result */
824 gst_object_unref (provider);
825 GST_OBJECT_UNLOCK (bin);
831 if ((result = bin->provided_clock))
832 gst_object_ref (result);
833 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
834 GST_OBJECT_UNLOCK (bin);
841 * functions for manipulating cached messages
846 GstMessageType types;
849 /* check if a message is of given src and type */
851 message_check (GstMessage * message, MessageFind * target)
856 eq &= GST_MESSAGE_SRC (message) == target->src;
858 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
859 GST_LOG ("looking at message %p: %d", message, eq);
865 find_message (GstBin * bin, GstObject * src, GstMessageType types)
873 result = g_list_find_custom (bin->messages, &find,
874 (GCompareFunc) message_check);
877 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
878 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
881 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
882 #ifndef GST_DISABLE_GST_DEBUG
886 for (i = 0; i < 32; i++)
887 if (types & (1 << i))
888 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1 << i));
896 /* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
899 * A message that is cached and has the same SRC and type is replaced
900 * by the given message.
903 bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
909 if ((src = GST_MESSAGE_SRC (message))) {
910 /* first find the previous message posted by this element */
911 if ((previous = find_message (bin, src, types))) {
912 GstMessage *previous_msg;
914 /* if we found a previous message, replace it */
915 previous_msg = previous->data;
916 previous->data = message;
918 GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
919 GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
920 GST_MESSAGE_TYPE_NAME (message));
922 gst_message_unref (previous_msg);
924 /* keep new message */
925 bin->messages = g_list_prepend (bin->messages, message);
927 GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
928 message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
931 GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
932 GST_MESSAGE_TYPE_NAME (message));
934 gst_message_unref (message);
939 /* with LOCK. Remove all messages of given types */
941 bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
949 for (walk = bin->messages; walk; walk = next) {
950 GstMessage *message = (GstMessage *) walk->data;
952 next = g_list_next (walk);
954 if (message_check (message, &find) == 0) {
955 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
956 "deleting message %p of types 0x%08x", message, types);
957 bin->messages = g_list_delete_link (bin->messages, walk);
958 gst_message_unref (message);
960 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
961 "not deleting message %p of type 0x%08x", message,
962 GST_MESSAGE_TYPE (message));
968 /* Check if the bin is EOS. We do this by scanning all sinks and
969 * checking if they posted an EOS message.
971 * call with bin LOCK */
973 is_eos (GstBin * bin, guint32 * seqnum)
980 for (walk = bin->children; walk; walk = g_list_next (walk)) {
983 element = GST_ELEMENT_CAST (walk->data);
984 if (bin_element_is_sink (element, bin) == 0) {
985 /* check if element posted EOS */
987 find_message (bin, GST_OBJECT_CAST (element), GST_MESSAGE_EOS))) {
988 GST_DEBUG ("sink '%s' posted EOS", GST_ELEMENT_NAME (element));
989 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
992 GST_DEBUG ("sink '%s' did not post EOS yet",
993 GST_ELEMENT_NAME (element));
999 /* FIXME: Some tests (e.g. elements/capsfilter) use
1000 * pipelines with a dangling sinkpad but no sink element.
1001 * These tests assume that no EOS message is ever
1002 * posted on the bus so let's keep that behaviour.
1003 * In valid pipelines this doesn't make a difference.
1005 return result && n_eos > 0;
1009 /* Check if the bin is STREAM_START. We do this by scanning all sinks and
1010 * checking if they posted an STREAM_START message.
1012 * call with bin LOCK */
1014 is_stream_start (GstBin * bin, guint32 * seqnum)
1017 gint n_stream_start = 0;
1021 for (walk = bin->children; walk; walk = g_list_next (walk)) {
1022 GstElement *element;
1024 element = GST_ELEMENT_CAST (walk->data);
1025 if (bin_element_is_sink (element, bin) == 0) {
1026 /* check if element posted STREAM_START */
1028 find_message (bin, GST_OBJECT_CAST (element),
1029 GST_MESSAGE_STREAM_START))) {
1030 GST_DEBUG ("sink '%s' posted STREAM_START", GST_ELEMENT_NAME (element));
1031 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1034 GST_DEBUG ("sink '%s' did not post STREAM_START yet",
1035 GST_ELEMENT_NAME (element));
1046 unlink_pads (const GValue * item, gpointer user_data)
1051 pad = g_value_get_object (item);
1053 if ((peer = gst_pad_get_peer (pad))) {
1054 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
1055 gst_pad_unlink (pad, peer);
1057 gst_pad_unlink (peer, pad);
1058 gst_object_unref (peer);
1062 /* vmethod that adds an element to a bin
1067 gst_bin_add_func (GstBin * bin, GstElement * element)
1071 gboolean is_sink, is_source, provides_clock, requires_clock;
1072 GstMessage *clock_message = NULL, *async_message = NULL;
1073 GstStateChangeReturn ret;
1075 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1077 /* we obviously can't add ourself to ourself */
1078 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1081 /* get the element name to make sure it is unique in this bin. */
1082 GST_OBJECT_LOCK (element);
1083 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1084 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1085 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1087 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1089 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1090 GST_OBJECT_UNLOCK (element);
1092 GST_OBJECT_LOCK (bin);
1094 /* then check to see if the element's name is already taken in the bin,
1095 * we can safely take the lock here. This check is probably bogus because
1096 * you can safely change the element name after this check and before setting
1097 * the object parent. The window is very small though... */
1098 if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
1099 goto duplicate_name;
1101 /* set the element's parent and add the element to the bin's list of children */
1102 if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
1103 GST_OBJECT_CAST (bin))))
1106 /* if we add a sink we become a sink */
1108 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
1110 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SINK);
1113 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was source",
1115 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SOURCE);
1117 if (provides_clock) {
1118 GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
1120 gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
1121 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1123 if (requires_clock) {
1124 GST_DEBUG_OBJECT (bin, "element \"%s\" requires a clock", elem_name);
1125 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1128 bin->children = g_list_prepend (bin->children, element);
1130 bin->children_cookie++;
1131 if (!GST_BIN_IS_NO_RESYNC (bin))
1132 bin->priv->structure_cookie++;
1134 /* distribute the bus */
1135 gst_element_set_bus (element, bin->child_bus);
1137 /* propagate the current base_time, start_time and clock */
1138 gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
1139 gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
1140 /* it's possible that the element did not accept the clock but
1141 * that is not important right now. When the pipeline goes to PLAYING,
1142 * a new clock will be selected */
1143 gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
1145 if (GST_ELEMENT_CAST (bin)->context)
1146 gst_element_set_context (element, GST_ELEMENT_CAST (bin)->context);
1149 /* set the cached index on the children */
1150 if (bin->priv->index)
1151 gst_element_set_index (element, bin->priv->index);
1154 ret = GST_STATE_RETURN (bin);
1155 /* no need to update the state if we are in error */
1156 if (ret == GST_STATE_CHANGE_FAILURE)
1157 goto no_state_recalc;
1159 /* update the bin state, the new element could have been an ASYNC or
1160 * NO_PREROLL element */
1161 ret = GST_STATE_RETURN (element);
1162 GST_DEBUG_OBJECT (bin, "added %s element",
1163 gst_element_state_change_return_get_name (ret));
1166 case GST_STATE_CHANGE_ASYNC:
1168 /* create message to track this aync element when it posts an async-done
1170 async_message = gst_message_new_async_start (GST_OBJECT_CAST (element));
1173 case GST_STATE_CHANGE_NO_PREROLL:
1174 /* ignore all async elements we might have and commit our state */
1175 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1177 case GST_STATE_CHANGE_FAILURE:
1184 GST_OBJECT_UNLOCK (bin);
1186 /* post the messages on the bus of the element so that the bin can handle
1189 gst_element_post_message (element, clock_message);
1192 gst_element_post_message (element, async_message);
1194 /* unlink all linked pads */
1195 it = gst_element_iterate_pads (element);
1196 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1197 gst_iterator_free (it);
1199 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
1202 g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
1203 gst_child_proxy_child_added ((GstChildProxy *) bin, (GObject *) element,
1210 /* ERROR handling here */
1213 GST_OBJECT_LOCK (bin);
1214 g_warning ("Cannot add bin '%s' to itself", GST_ELEMENT_NAME (bin));
1215 GST_OBJECT_UNLOCK (bin);
1220 g_warning ("Name '%s' is not unique in bin '%s', not adding",
1221 elem_name, GST_ELEMENT_NAME (bin));
1222 GST_OBJECT_UNLOCK (bin);
1228 g_warning ("Element '%s' already has parent", elem_name);
1229 GST_OBJECT_UNLOCK (bin);
1238 * @element: (transfer full): the #GstElement to add
1240 * Adds the given element to the bin. Sets the element's parent, and thus
1241 * takes ownership of the element. An element can only be added to one bin.
1243 * If the element's pads are linked to other pads, the pads will be unlinked
1244 * before the element is added to the bin.
1247 * When you add an element to an already-running pipeline, you will have to
1248 * take care to set the state of the newly-added element to the desired
1249 * state (usually PLAYING or PAUSED, same you set the pipeline to originally)
1250 * with gst_element_set_state(), or use gst_element_sync_state_with_parent().
1251 * The bin or pipeline will not take care of this for you.
1256 * Returns: TRUE if the element could be added, FALSE if
1257 * the bin does not want to accept the element.
1260 gst_bin_add (GstBin * bin, GstElement * element)
1262 GstBinClass *bclass;
1265 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1266 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1268 bclass = GST_BIN_GET_CLASS (bin);
1270 if (G_UNLIKELY (bclass->add_element == NULL))
1273 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1274 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1275 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1277 result = bclass->add_element (bin, element);
1281 /* ERROR handling */
1284 g_warning ("adding elements to bin '%s' is not supported",
1285 GST_ELEMENT_NAME (bin));
1290 /* remove an element from the bin
1295 gst_bin_remove_func (GstBin * bin, GstElement * element)
1299 gboolean is_sink, is_source, provides_clock, requires_clock;
1300 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1301 GstMessage *clock_message = NULL;
1302 GstClock **provided_clock_p;
1303 GstElement **clock_provider_p;
1305 gboolean other_async, this_async, have_no_preroll;
1306 GstStateChangeReturn ret;
1308 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1310 GST_OBJECT_LOCK (bin);
1312 GST_OBJECT_LOCK (element);
1313 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1315 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1318 /* remove the parent ref */
1319 GST_OBJECT_PARENT (element) = NULL;
1321 /* grab element name so we can print it */
1322 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1323 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1325 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1327 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1328 GST_OBJECT_UNLOCK (element);
1332 othersource = FALSE;
1333 otherprovider = FALSE;
1334 otherrequirer = FALSE;
1335 have_no_preroll = FALSE;
1336 /* iterate the elements, we collect which ones are async and no_preroll. We
1337 * also remove the element when we find it. */
1338 for (walk = bin->children; walk; walk = next) {
1339 GstElement *child = GST_ELEMENT_CAST (walk->data);
1341 next = g_list_next (walk);
1343 if (child == element) {
1345 /* remove the element */
1346 bin->children = g_list_delete_link (bin->children, walk);
1348 gboolean child_sink, child_source, child_provider, child_requirer;
1350 GST_OBJECT_LOCK (child);
1351 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1352 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1354 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1356 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1357 /* when we remove a sink, check if there are other sinks. */
1358 if (is_sink && !othersink && child_sink)
1360 if (is_source && !othersource && child_source)
1362 if (provides_clock && !otherprovider && child_provider)
1363 otherprovider = TRUE;
1364 if (requires_clock && !otherrequirer && child_requirer)
1365 otherrequirer = TRUE;
1366 /* check if we have NO_PREROLL children */
1367 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1368 have_no_preroll = TRUE;
1369 GST_OBJECT_UNLOCK (child);
1373 /* the element must have been in the bin's list of children */
1374 if (G_UNLIKELY (!found))
1377 /* we now removed the element from the list of elements, increment the cookie
1378 * so that others can detect a change in the children list. */
1380 bin->children_cookie++;
1381 if (!GST_BIN_IS_NO_RESYNC (bin))
1382 bin->priv->structure_cookie++;
1384 if (is_sink && !othersink) {
1385 /* we're not a sink anymore */
1386 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1387 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1389 if (is_source && !othersource) {
1390 /* we're not a source anymore */
1391 GST_DEBUG_OBJECT (bin, "we removed the last source");
1392 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1394 if (provides_clock && !otherprovider) {
1395 /* we're not a clock provider anymore */
1396 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1397 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1399 if (requires_clock && !otherrequirer) {
1400 /* we're not a clock requirer anymore */
1401 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1402 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1405 /* if the clock provider for this element is removed, we lost
1406 * the clock as well, we need to inform the parent of this
1407 * so that it can select a new clock */
1408 if (bin->clock_provider == element) {
1409 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1410 bin->clock_dirty = TRUE;
1412 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1413 provided_clock_p = &bin->provided_clock;
1414 clock_provider_p = &bin->clock_provider;
1415 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1416 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1419 /* remove messages for the element, if there was a pending ASYNC_START
1420 * message we must see if removing the element caused the bin to lose its
1423 other_async = FALSE;
1424 for (walk = bin->messages; walk; walk = next) {
1425 GstMessage *message = (GstMessage *) walk->data;
1426 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1429 next = g_list_next (walk);
1432 switch (GST_MESSAGE_TYPE (message)) {
1433 case GST_MESSAGE_ASYNC_START:
1439 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1441 case GST_MESSAGE_STRUCTURE_CHANGE:
1445 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1447 /* it's unlikely that this message is still in the list of messages
1448 * because this would mean that a link/unlink is busy in another thread
1449 * while we remove the element. We still have to remove the message
1450 * because we might not receive the done message anymore when the element
1451 * is removed from the bin. */
1452 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1453 if (owner == element)
1464 /* delete all message types */
1465 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1466 message, elem_name);
1467 bin->messages = g_list_delete_link (bin->messages, walk);
1468 gst_message_unref (message);
1472 /* get last return */
1473 ret = GST_STATE_RETURN (bin);
1475 /* no need to update the state if we are in error */
1476 if (ret == GST_STATE_CHANGE_FAILURE)
1477 goto no_state_recalc;
1479 if (!other_async && this_async) {
1480 /* all other elements were not async and we removed the async one,
1481 * handle the async-done case because we are not async anymore now. */
1482 GST_DEBUG_OBJECT (bin,
1483 "we removed the last async element, have no_preroll %d",
1486 /* the current state return of the bin depends on if there are no_preroll
1487 * elements in the pipeline or not */
1488 if (have_no_preroll)
1489 ret = GST_STATE_CHANGE_NO_PREROLL;
1491 ret = GST_STATE_CHANGE_SUCCESS;
1493 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1495 GST_DEBUG_OBJECT (bin,
1496 "recalc state preroll: %d, other async: %d, this async %d",
1497 have_no_preroll, other_async, this_async);
1499 if (have_no_preroll) {
1500 ret = GST_STATE_CHANGE_NO_PREROLL;
1501 } else if (other_async) {
1502 /* there are other async elements and we were not doing an async state
1503 * change, change our pending state and go async */
1504 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1505 GST_STATE_NEXT (bin) = GST_STATE (bin);
1506 GST_STATE_PENDING (bin) = GST_STATE (bin);
1508 ret = GST_STATE_CHANGE_ASYNC;
1510 GST_STATE_RETURN (bin) = ret;
1514 gst_element_set_bus (element, NULL);
1515 /* Clear the clock we provided to the element */
1516 gst_element_set_clock (element, NULL);
1517 GST_OBJECT_UNLOCK (bin);
1520 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1522 /* unlink all linked pads */
1523 it = gst_element_iterate_pads (element);
1524 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1525 gst_iterator_free (it);
1527 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1530 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1531 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1535 /* element is really out of our control now */
1536 gst_object_unref (element);
1540 /* ERROR handling */
1543 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1544 GST_ELEMENT_NAME (bin));
1545 GST_OBJECT_UNLOCK (element);
1546 GST_OBJECT_UNLOCK (bin);
1555 * @element: (transfer none): the #GstElement to remove
1557 * Removes the element from the bin, unparenting it as well.
1558 * Unparenting the element means that the element will be dereferenced,
1559 * so if the bin holds the only reference to the element, the element
1560 * will be freed in the process of removing it from the bin. If you
1561 * want the element to still exist after removing, you need to call
1562 * gst_object_ref() before removing it from the bin.
1564 * If the element's pads are linked to other pads, the pads will be unlinked
1565 * before the element is removed from the bin.
1569 * Returns: TRUE if the element could be removed, FALSE if
1570 * the bin does not want to remove the element.
1573 gst_bin_remove (GstBin * bin, GstElement * element)
1575 GstBinClass *bclass;
1578 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1579 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1581 bclass = GST_BIN_GET_CLASS (bin);
1583 if (G_UNLIKELY (bclass->remove_element == NULL))
1586 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1587 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1589 result = bclass->remove_element (bin, element);
1593 /* ERROR handling */
1596 g_warning ("removing elements from bin '%s' is not supported",
1597 GST_ELEMENT_NAME (bin));
1603 * gst_bin_iterate_elements:
1606 * Gets an iterator for the elements in this bin.
1608 * MT safe. Caller owns returned value.
1610 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1613 gst_bin_iterate_elements (GstBin * bin)
1615 GstIterator *result;
1617 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1619 GST_OBJECT_LOCK (bin);
1620 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1621 GST_OBJECT_GET_LOCK (bin),
1622 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1623 GST_OBJECT_UNLOCK (bin);
1628 static GstIteratorItem
1629 iterate_child_recurse (GstIterator * it, const GValue * item)
1631 GstElement *child = g_value_get_object (item);
1633 if (GST_IS_BIN (child)) {
1634 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1636 gst_iterator_push (it, other);
1638 return GST_ITERATOR_ITEM_PASS;
1642 * gst_bin_iterate_recurse:
1645 * Gets an iterator for the elements in this bin.
1646 * This iterator recurses into GstBin children.
1648 * MT safe. Caller owns returned value.
1650 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1653 gst_bin_iterate_recurse (GstBin * bin)
1655 GstIterator *result;
1657 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1659 GST_OBJECT_LOCK (bin);
1660 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1661 GST_OBJECT_GET_LOCK (bin),
1662 &bin->children_cookie,
1664 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1665 GST_OBJECT_UNLOCK (bin);
1670 /* returns 0 when TRUE because this is a GCompareFunc */
1673 bin_element_is_sink (GstElement * child, GstBin * bin)
1677 /* we lock the child here for the remainder of the function to
1678 * get its name and flag safely. */
1679 GST_OBJECT_LOCK (child);
1680 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1682 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1683 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1685 GST_OBJECT_UNLOCK (child);
1686 return is_sink ? 0 : 1;
1690 sink_iterator_filter (const GValue * vchild, GValue * vbin)
1692 GstBin *bin = g_value_get_object (vbin);
1693 GstElement *child = g_value_get_object (vchild);
1695 return (bin_element_is_sink (child, bin));
1699 * gst_bin_iterate_sinks:
1702 * Gets an iterator for all elements in the bin that have the
1703 * #GST_ELEMENT_FLAG_SINK flag set.
1705 * MT safe. Caller owns returned value.
1707 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1710 gst_bin_iterate_sinks (GstBin * bin)
1712 GstIterator *children;
1713 GstIterator *result;
1714 GValue vbin = { 0, };
1716 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1718 g_value_init (&vbin, GST_TYPE_BIN);
1719 g_value_set_object (&vbin, bin);
1721 children = gst_bin_iterate_elements (bin);
1722 result = gst_iterator_filter (children,
1723 (GCompareFunc) sink_iterator_filter, &vbin);
1725 g_value_unset (&vbin);
1730 /* returns 0 when TRUE because this is a GCompareFunc */
1733 bin_element_is_src (GstElement * child, GstBin * bin)
1737 /* we lock the child here for the remainder of the function to
1738 * get its name and other info safely. */
1739 GST_OBJECT_LOCK (child);
1740 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1742 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1743 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
1745 GST_OBJECT_UNLOCK (child);
1746 return is_src ? 0 : 1;
1750 src_iterator_filter (const GValue * vchild, GValue * vbin)
1752 GstBin *bin = g_value_get_object (vbin);
1753 GstElement *child = g_value_get_object (vchild);
1755 return (bin_element_is_src (child, bin));
1759 * gst_bin_iterate_sources:
1762 * Gets an iterator for all elements in the bin that have the
1763 * #GST_ELEMENT_FLAG_SOURCE flag set.
1765 * MT safe. Caller owns returned value.
1767 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1770 gst_bin_iterate_sources (GstBin * bin)
1772 GstIterator *children;
1773 GstIterator *result;
1774 GValue vbin = { 0, };
1776 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1778 g_value_init (&vbin, GST_TYPE_BIN);
1779 g_value_set_object (&vbin, bin);
1781 children = gst_bin_iterate_elements (bin);
1782 result = gst_iterator_filter (children,
1783 (GCompareFunc) src_iterator_filter, &vbin);
1785 g_value_unset (&vbin);
1793 static GstStateChangeReturn
1794 gst_bin_get_state_func (GstElement * element, GstState * state,
1795 GstState * pending, GstClockTime timeout)
1797 GstStateChangeReturn ret;
1799 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
1802 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
1808 /***********************************************
1809 * Topologically sorted iterator
1810 * see http://en.wikipedia.org/wiki/Topological_sorting
1812 * For each element in the graph, an entry is kept in a HashTable
1813 * with its number of srcpad connections (degree).
1814 * We then change state of all elements without dependencies
1815 * (degree 0) and decrement the degree of all elements connected
1816 * on the sinkpads. When an element reaches degree 0, its state is
1818 * When all elements are handled the algorithm stops.
1820 typedef struct _GstBinSortIterator
1823 GQueue queue; /* elements queued for state change */
1824 GstBin *bin; /* bin we iterate */
1825 gint mode; /* adding or removing dependency */
1826 GstElement *best; /* next element with least dependencies */
1827 gint best_deg; /* best degree */
1828 GHashTable *hash; /* hashtable with element dependencies */
1829 gboolean dirty; /* we detected structure change */
1830 } GstBinSortIterator;
1833 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
1834 GstBinSortIterator * copy)
1836 GHashTableIter iter;
1837 gpointer key, value;
1839 copy->queue = it->queue;
1840 g_queue_foreach (©->queue, (GFunc) gst_object_ref, NULL);
1842 copy->bin = gst_object_ref (it->bin);
1844 copy->best = gst_object_ref (it->best);
1846 copy->hash = g_hash_table_new (NULL, NULL);
1847 g_hash_table_iter_init (&iter, it->hash);
1848 while (g_hash_table_iter_next (&iter, &key, &value))
1849 g_hash_table_insert (copy->hash, key, value);
1852 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
1853 #define HASH_SET_DEGREE(bit, elem, deg) \
1854 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
1855 #define HASH_GET_DEGREE(bit, elem) \
1856 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
1858 /* add element to queue of next elements in the iterator.
1859 * We push at the tail to give higher priority elements a
1862 add_to_queue (GstBinSortIterator * bit, GstElement * element)
1864 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
1865 GST_ELEMENT_NAME (element));
1866 gst_object_ref (element);
1867 g_queue_push_tail (&bit->queue, element);
1868 HASH_SET_DEGREE (bit, element, -1);
1872 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
1876 if ((find = g_queue_find (&bit->queue, element))) {
1877 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
1878 GST_ELEMENT_NAME (element));
1880 g_queue_delete_link (&bit->queue, find);
1881 gst_object_unref (element);
1883 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
1884 GST_ELEMENT_NAME (element));
1888 /* clear the queue, unref all objects as we took a ref when
1889 * we added them to the queue */
1891 clear_queue (GQueue * queue)
1895 while ((p = g_queue_pop_head (queue)))
1896 gst_object_unref (p);
1899 /* set all degrees to 0. Elements marked as a sink are
1900 * added to the queue immediately. Since we only look at the SINK flag of the
1901 * element, it is possible that we add non-sinks to the queue. These will be
1902 * removed from the queue again when we can prove that it provides data for some
1905 reset_degree (GstElement * element, GstBinSortIterator * bit)
1909 /* sinks are added right away */
1910 GST_OBJECT_LOCK (element);
1911 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1912 GST_OBJECT_UNLOCK (element);
1915 add_to_queue (bit, element);
1917 /* others are marked with 0 and handled when sinks are done */
1918 HASH_SET_DEGREE (bit, element, 0);
1922 /* adjust the degree of all elements connected to the given
1923 * element. If a degree of an element drops to 0, it is
1924 * added to the queue of elements to schedule next.
1926 * We have to make sure not to cross the bin boundary this element
1930 update_degree (GstElement * element, GstBinSortIterator * bit)
1932 gboolean linked = FALSE;
1934 GST_OBJECT_LOCK (element);
1935 /* don't touch degree if element has no sinkpads */
1936 if (element->numsinkpads != 0) {
1937 /* loop over all sinkpads, decrement degree for all connected
1938 * elements in this bin */
1941 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
1944 pad = GST_PAD_CAST (pads->data);
1946 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
1947 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
1948 GST_MESSAGE_STRUCTURE_CHANGE))) {
1949 /* mark the iterator as dirty because we won't be updating the degree
1950 * of the peer parent now. This would result in the 'loop detected'
1951 * later on because the peer parent element could become the best next
1952 * element with a degree > 0. We will simply continue our state
1953 * changes and we'll eventually resync when the unlink completed and
1954 * the iterator cookie is updated. */
1959 if ((peer = gst_pad_get_peer (pad))) {
1960 GstElement *peer_element;
1962 if ((peer_element = gst_pad_get_parent_element (peer))) {
1963 GST_OBJECT_LOCK (peer_element);
1964 /* check that we don't go outside of this bin */
1965 if (GST_OBJECT_CAST (peer_element)->parent ==
1966 GST_OBJECT_CAST (bit->bin)) {
1967 gint old_deg, new_deg;
1969 old_deg = HASH_GET_DEGREE (bit, peer_element);
1971 /* check to see if we added an element as sink that was not really a
1972 * sink because it was connected to some other element. */
1973 if (old_deg == -1) {
1974 remove_from_queue (bit, peer_element);
1977 new_deg = old_deg + bit->mode;
1979 GST_DEBUG_OBJECT (bit->bin,
1980 "change element %s, degree %d->%d, linked to %s",
1981 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
1982 GST_ELEMENT_NAME (element));
1984 /* update degree, it is possible that an element was in 0 and
1985 * reaches -1 here. This would mean that the element had no sinkpads
1986 * but became linked while the state change was happening. We will
1987 * resync on this with the structure change message. */
1989 /* degree hit 0, add to queue */
1990 add_to_queue (bit, peer_element);
1992 HASH_SET_DEGREE (bit, peer_element, new_deg);
1996 GST_OBJECT_UNLOCK (peer_element);
1997 gst_object_unref (peer_element);
1999 gst_object_unref (peer);
2004 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2005 GST_ELEMENT_NAME (element));
2007 GST_OBJECT_UNLOCK (element);
2010 /* find the next best element not handled yet. This is the one
2011 * with the lowest non-negative degree */
2013 find_element (GstElement * element, GstBinSortIterator * bit)
2017 /* element is already handled */
2018 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2021 /* first element or element with smaller degree */
2022 if (bit->best == NULL || bit->best_deg > degree) {
2023 bit->best = element;
2024 bit->best_deg = degree;
2028 /* get next element in iterator. */
2029 static GstIteratorResult
2030 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2033 GstBin *bin = bit->bin;
2035 /* empty queue, we have to find a next best element */
2036 if (g_queue_is_empty (&bit->queue)) {
2038 bit->best_deg = G_MAXINT;
2039 g_list_foreach (bin->children, (GFunc) find_element, bit);
2040 if ((best = bit->best)) {
2041 /* when we detected an unlink, don't warn because our degrees might be
2042 * screwed up. We will resync later */
2043 if (bit->best_deg != 0 && !bit->dirty) {
2044 /* we don't fail on this one yet */
2045 GST_WARNING_OBJECT (bin, "loop dected in graph");
2046 g_warning ("loop detected in the graph of bin '%s'!!",
2047 GST_ELEMENT_NAME (bin));
2049 /* best unhandled element, schedule as next element */
2050 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2051 GST_ELEMENT_NAME (best));
2052 HASH_SET_DEGREE (bit, best, -1);
2053 g_value_set_object (result, best);
2055 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2056 /* no more unhandled elements, we are done */
2057 return GST_ITERATOR_DONE;
2060 /* everything added to the queue got reffed */
2061 best = g_queue_pop_head (&bit->queue);
2062 g_value_set_object (result, best);
2063 gst_object_unref (best);
2066 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2067 /* update degrees of linked elements */
2068 update_degree (best, bit);
2070 return GST_ITERATOR_OK;
2073 /* clear queues, recalculate the degrees and restart. */
2075 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2077 GstBin *bin = bit->bin;
2079 GST_DEBUG_OBJECT (bin, "resync");
2081 clear_queue (&bit->queue);
2083 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2084 /* calc degrees, incrementing */
2086 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2087 /* for the rest of the function we decrement the degrees */
2091 /* clear queues, unref bin and free iterator. */
2093 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2095 GstBin *bin = bit->bin;
2097 GST_DEBUG_OBJECT (bin, "free");
2098 clear_queue (&bit->queue);
2099 g_hash_table_destroy (bit->hash);
2100 gst_object_unref (bin);
2103 /* should be called with the bin LOCK held */
2104 static GstIterator *
2105 gst_bin_sort_iterator_new (GstBin * bin)
2107 GstBinSortIterator *result;
2109 /* we don't need an ItemFunction because we ref the items in the _next
2111 result = (GstBinSortIterator *)
2112 gst_iterator_new (sizeof (GstBinSortIterator),
2114 GST_OBJECT_GET_LOCK (bin),
2115 &bin->priv->structure_cookie,
2116 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2117 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2118 (GstIteratorItemFunction) NULL,
2119 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2120 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2121 g_queue_init (&result->queue);
2122 result->hash = g_hash_table_new (NULL, NULL);
2123 gst_object_ref (bin);
2125 gst_bin_sort_iterator_resync (result);
2127 return (GstIterator *) result;
2131 * gst_bin_iterate_sorted:
2134 * Gets an iterator for the elements in this bin in topologically
2135 * sorted order. This means that the elements are returned from
2136 * the most downstream elements (sinks) to the sources.
2138 * This function is used internally to perform the state changes
2139 * of the bin elements and for clock selection.
2141 * MT safe. Caller owns returned value.
2143 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
2146 gst_bin_iterate_sorted (GstBin * bin)
2148 GstIterator *result;
2150 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2152 GST_OBJECT_LOCK (bin);
2153 result = gst_bin_sort_iterator_new (bin);
2154 GST_OBJECT_UNLOCK (bin);
2159 static GstStateChangeReturn
2160 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2161 GstClockTime base_time, GstClockTime start_time, GstState current,
2164 GstStateChangeReturn ret;
2165 GstState child_current, child_pending;
2169 GST_STATE_LOCK (element);
2171 GST_OBJECT_LOCK (element);
2172 /* set base_time and start time on child */
2173 GST_ELEMENT_START_TIME (element) = start_time;
2174 element->base_time = base_time;
2175 /* peel off the locked flag */
2176 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2177 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2178 ret = GST_STATE_RETURN (element);
2179 child_current = GST_STATE (element);
2180 child_pending = GST_STATE_PENDING (element);
2181 GST_OBJECT_UNLOCK (element);
2183 /* skip locked elements */
2184 if (G_UNLIKELY (locked))
2187 /* if the element was no preroll, just start changing the state regardless
2188 * if it had async elements (in the case of a bin) because they won't preroll
2190 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2191 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2195 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2196 "current %s pending %s, desired next %s",
2197 gst_element_state_get_name (child_current),
2198 gst_element_state_get_name (child_pending),
2199 gst_element_state_get_name (next));
2201 /* always recurse into bins so that we can set the base time */
2202 if (GST_IS_BIN (element))
2205 /* Try not to change the state of elements that are already in the state we're
2207 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2208 /* child is already at the requested state, return previous return. Note that
2209 * if the child has a pending state to next, we will still call the
2210 * set_state function */
2212 } else if (next > current) {
2213 /* upward state change */
2214 if (child_pending == GST_STATE_VOID_PENDING) {
2215 /* .. and the child is not busy doing anything */
2216 if (child_current > next) {
2217 /* .. and is already past the requested state, assume it got there
2219 ret = GST_STATE_CHANGE_SUCCESS;
2222 } else if (child_pending > child_current) {
2223 /* .. and the child is busy going upwards */
2224 if (child_current >= next) {
2225 /* .. and is already past the requested state, assume it got there
2227 ret = GST_STATE_CHANGE_SUCCESS;
2231 /* .. and the child is busy going downwards */
2232 if (child_current > next) {
2233 /* .. and is already past the requested state, assume it got there
2235 ret = GST_STATE_CHANGE_SUCCESS;
2239 } else if (next < current) {
2240 /* downward state change */
2241 if (child_pending == GST_STATE_VOID_PENDING) {
2242 /* .. and the child is not busy doing anything */
2243 if (child_current < next) {
2244 /* .. and is already past the requested state, assume it got there
2246 ret = GST_STATE_CHANGE_SUCCESS;
2249 } else if (child_pending < child_current) {
2250 /* .. and the child is busy going downwards */
2251 if (child_current <= next) {
2252 /* .. and is already past the requested state, assume it got there
2254 ret = GST_STATE_CHANGE_SUCCESS;
2258 /* .. and the child is busy going upwards */
2259 if (child_current < next) {
2260 /* .. and is already past the requested state, assume it got there
2262 ret = GST_STATE_CHANGE_SUCCESS;
2269 GST_OBJECT_LOCK (bin);
2270 /* the element was busy with an upwards async state change, we must wait for
2271 * an ASYNC_DONE message before we attemp to change the state. */
2273 find_message (bin, GST_OBJECT_CAST (element),
2274 GST_MESSAGE_ASYNC_START))) {
2275 #ifndef GST_DISABLE_GST_DEBUG
2276 GstMessage *message = GST_MESSAGE_CAST (found->data);
2278 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2279 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2281 /* only wait for upward state changes */
2282 if (next > current) {
2283 /* We found an async element check if we can force its state to change or
2284 * if we have to wait for it to preroll. */
2288 GST_OBJECT_UNLOCK (bin);
2291 GST_DEBUG_OBJECT (bin,
2292 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2293 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2294 GST_TIME_ARGS (base_time));
2297 ret = gst_element_set_state (element, next);
2299 GST_STATE_UNLOCK (element);
2305 GST_DEBUG_OBJECT (element,
2306 "element is locked, return previous return %s",
2307 gst_element_state_change_return_get_name (ret));
2308 GST_STATE_UNLOCK (element);
2313 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2314 "skipping transition from %s to %s",
2315 gst_element_state_get_name (child_current),
2316 gst_element_state_get_name (next));
2317 GST_STATE_UNLOCK (element);
2322 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2323 GST_OBJECT_UNLOCK (bin);
2324 GST_STATE_UNLOCK (element);
2325 return GST_STATE_CHANGE_ASYNC;
2329 /* gst_iterator_fold functions for pads_activate
2330 * Stop the iterator if activating one pad failed. */
2332 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2334 GstPad *pad = g_value_get_object (vpad);
2335 gboolean cont = TRUE;
2337 if (!(cont = gst_pad_set_active (pad, *active)))
2338 g_value_set_boolean (ret, FALSE);
2343 /* returns false on error or early cutout of the fold, true if all
2344 * pads in @iter were (de)activated successfully. */
2346 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2348 GstIteratorResult ires;
2351 /* no need to unset this later, it's just a boolean */
2352 g_value_init (&ret, G_TYPE_BOOLEAN);
2353 g_value_set_boolean (&ret, TRUE);
2356 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2359 case GST_ITERATOR_RESYNC:
2360 /* need to reset the result again */
2361 g_value_set_boolean (&ret, TRUE);
2362 gst_iterator_resync (iter);
2364 case GST_ITERATOR_DONE:
2365 /* all pads iterated, return collected value */
2368 /* iterator returned _ERROR or premature end with _OK,
2369 * mark an error and exit */
2370 g_value_set_boolean (&ret, FALSE);
2375 /* return collected value */
2376 return g_value_get_boolean (&ret);
2379 /* is called with STATE_LOCK
2382 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2387 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2389 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2390 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2391 gst_iterator_free (iter);
2392 if (G_UNLIKELY (!fold_ok))
2395 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2402 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2408 * gst_bin_recalculate_latency:
2411 * Query @bin for the current latency using and reconfigures this latency to all the
2412 * elements with a LATENCY event.
2414 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2415 * is posted on the bus.
2417 * This function simply emits the 'do-latency' signal so any custom latency
2418 * calculations will be performed.
2420 * Returns: %TRUE if the latency could be queried and reconfigured.
2423 gst_bin_recalculate_latency (GstBin * bin)
2427 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2428 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2434 gst_bin_do_latency_func (GstBin * bin)
2437 GstElement *element;
2438 GstClockTime min_latency, max_latency;
2441 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2443 element = GST_ELEMENT_CAST (bin);
2445 GST_DEBUG_OBJECT (element, "querying latency");
2447 query = gst_query_new_latency ();
2448 if ((res = gst_element_query (element, query))) {
2451 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2453 GST_DEBUG_OBJECT (element,
2454 "got min latency %" GST_TIME_FORMAT ", max latency %"
2455 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2456 GST_TIME_ARGS (max_latency), live);
2458 if (max_latency < min_latency) {
2459 /* this is an impossible situation, some parts of the pipeline might not
2460 * work correctly. We post a warning for now. */
2461 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2462 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2463 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2464 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2467 /* configure latency on elements */
2468 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2470 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2471 GST_TIME_ARGS (min_latency));
2473 GST_WARNING_OBJECT (element,
2474 "did not really configure latency of %" GST_TIME_FORMAT,
2475 GST_TIME_ARGS (min_latency));
2478 /* this is not a real problem, we just don't configure any latency. */
2479 GST_WARNING_OBJECT (element, "failed to query latency");
2481 gst_query_unref (query);
2487 gst_bin_state_changed (GstElement * element, GstState oldstate,
2488 GstState newstate, GstState pending)
2490 GstElementClass *pklass = (GstElementClass *) parent_class;
2492 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING)
2493 bin_do_eos (GST_BIN_CAST (element));
2495 if (pklass->state_changed)
2496 pklass->state_changed (element, oldstate, newstate, pending);
2499 static GstStateChangeReturn
2500 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2503 GstStateChangeReturn ret;
2504 GstState current, next;
2505 gboolean have_async;
2506 gboolean have_no_preroll;
2507 GstClockTime base_time, start_time;
2510 GValue data = { 0, };
2512 /* we don't need to take the STATE_LOCK, it is already taken */
2513 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2514 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2516 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2517 "changing state of children from %s to %s",
2518 gst_element_state_get_name (current), gst_element_state_get_name (next));
2520 bin = GST_BIN_CAST (element);
2523 case GST_STATE_PLAYING:
2527 GST_OBJECT_LOCK (bin);
2528 toplevel = BIN_IS_TOPLEVEL (bin);
2529 GST_OBJECT_UNLOCK (bin);
2532 gst_bin_recalculate_latency (bin);
2535 case GST_STATE_PAUSED:
2536 /* Clear EOS list on next PAUSED */
2537 GST_OBJECT_LOCK (bin);
2538 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2539 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2540 bin->priv->posted_eos = FALSE;
2541 if (current == GST_STATE_READY)
2542 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2543 GST_OBJECT_UNLOCK (bin);
2544 if (current == GST_STATE_READY)
2545 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2546 goto activate_failure;
2548 case GST_STATE_READY:
2549 /* Clear message list on next READY */
2550 GST_OBJECT_LOCK (bin);
2551 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2552 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2553 GST_OBJECT_UNLOCK (bin);
2554 if (current == GST_STATE_PAUSED)
2555 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2556 goto activate_failure;
2558 case GST_STATE_NULL:
2559 if (current == GST_STATE_READY)
2560 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2561 goto activate_failure;
2567 /* this flag is used to make the async state changes return immediately. We
2568 * don't want them to interfere with this state change */
2569 GST_OBJECT_LOCK (bin);
2570 bin->polling = TRUE;
2571 GST_OBJECT_UNLOCK (bin);
2573 /* iterate in state change order */
2574 it = gst_bin_iterate_sorted (bin);
2576 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2577 * Note how we don't reset this value when a resync happens, the reason being
2578 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2579 * even after a resync when the async element is gone */
2583 /* take base_time */
2584 base_time = gst_element_get_base_time (element);
2585 start_time = gst_element_get_start_time (element);
2587 have_no_preroll = FALSE;
2591 switch (gst_iterator_next (it, &data)) {
2592 case GST_ITERATOR_OK:
2596 child = g_value_get_object (&data);
2598 /* set state and base_time now */
2599 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2603 case GST_STATE_CHANGE_SUCCESS:
2604 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2605 "child '%s' changed state to %d(%s) successfully",
2606 GST_ELEMENT_NAME (child), next,
2607 gst_element_state_get_name (next));
2609 case GST_STATE_CHANGE_ASYNC:
2611 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2612 "child '%s' is changing state asynchronously to %s",
2613 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2617 case GST_STATE_CHANGE_FAILURE:{
2620 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2621 "child '%s' failed to go to state %d(%s)",
2622 GST_ELEMENT_NAME (child),
2623 next, gst_element_state_get_name (next));
2625 /* Only fail if the child is still inside
2626 * this bin. It might've been removed already
2627 * because of the error by the bin subclass
2628 * to ignore the error. */
2629 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2630 if (parent == GST_OBJECT_CAST (element)) {
2631 /* element is still in bin, really error now */
2632 gst_object_unref (parent);
2635 /* child removed from bin, let the resync code redo the state
2637 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2638 "child '%s' was removed from the bin",
2639 GST_ELEMENT_NAME (child));
2642 gst_object_unref (parent);
2646 case GST_STATE_CHANGE_NO_PREROLL:
2647 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2648 "child '%s' changed state to %d(%s) successfully without preroll",
2649 GST_ELEMENT_NAME (child), next,
2650 gst_element_state_get_name (next));
2651 have_no_preroll = TRUE;
2654 g_assert_not_reached ();
2657 g_value_reset (&data);
2660 case GST_ITERATOR_RESYNC:
2661 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
2662 gst_iterator_resync (it);
2665 case GST_ITERATOR_DONE:
2666 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
2672 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
2673 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
2676 if (have_no_preroll) {
2677 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2678 "we have NO_PREROLL elements %s -> NO_PREROLL",
2679 gst_element_state_change_return_get_name (ret));
2680 ret = GST_STATE_CHANGE_NO_PREROLL;
2681 } else if (have_async) {
2682 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2683 "we have ASYNC elements %s -> ASYNC",
2684 gst_element_state_change_return_get_name (ret));
2685 ret = GST_STATE_CHANGE_ASYNC;
2689 g_value_unset (&data);
2690 gst_iterator_free (it);
2692 GST_OBJECT_LOCK (bin);
2693 bin->polling = FALSE;
2694 /* it's possible that we did not get ASYNC from the children while the bin is
2695 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
2696 * itself as the source. In that case we still want to check if the state
2697 * change completed. */
2698 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
2699 /* no element returned ASYNC and there are no pending async_done messages,
2700 * we can just complete. */
2701 GST_DEBUG_OBJECT (bin, "no async elements");
2704 /* when we get here an ASYNC element was found */
2705 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
2706 /* we ignore ASYNC state changes when we go to READY or NULL */
2707 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
2708 gst_element_state_get_name (GST_STATE_TARGET (bin)));
2712 GST_DEBUG_OBJECT (bin, "check async elements");
2713 /* check if all elements managed to commit their state already */
2714 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
2715 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
2716 * all the elements commited their state while we were doing the state
2717 * change. We will still return ASYNC for consistency but we commit the
2718 * state already so that a _get_state() will return immediately. */
2719 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
2721 GST_DEBUG_OBJECT (bin, "async elements commited");
2722 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
2723 GST_CLOCK_TIME_NONE);
2727 bin->priv->pending_async_done = FALSE;
2728 GST_OBJECT_UNLOCK (bin);
2730 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2731 "done changing bin's state from %s to %s, now in %s, ret %s",
2732 gst_element_state_get_name (current),
2733 gst_element_state_get_name (next),
2734 gst_element_state_get_name (GST_STATE (element)),
2735 gst_element_state_change_return_get_name (ret));
2742 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
2743 "failure (de)activating src pads");
2744 return GST_STATE_CHANGE_FAILURE;
2749 * This function is a utility event handler for seek events.
2750 * It will send the event to all sinks or sources and appropriate
2751 * ghost pads depending on the event-direction.
2753 * Applications are free to override this behaviour and
2754 * implement their own seek handler, but this will work for
2755 * pretty much all cases in practice.
2758 gst_bin_send_event (GstElement * element, GstEvent * event)
2760 GstBin *bin = GST_BIN_CAST (element);
2762 gboolean res = TRUE;
2763 gboolean done = FALSE;
2764 GValue data = { 0, };
2766 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2767 iter = gst_bin_iterate_sources (bin);
2768 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
2769 GST_EVENT_TYPE_NAME (event));
2771 iter = gst_bin_iterate_sinks (bin);
2772 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
2773 GST_EVENT_TYPE_NAME (event));
2777 switch (gst_iterator_next (iter, &data)) {
2778 case GST_ITERATOR_OK:
2780 GstElement *child = g_value_get_object (&data);
2782 gst_event_ref (event);
2783 res &= gst_element_send_event (child, event);
2785 GST_LOG_OBJECT (child, "After handling %s event: %d",
2786 GST_EVENT_TYPE_NAME (event), res);
2788 g_value_reset (&data);
2791 case GST_ITERATOR_RESYNC:
2792 gst_iterator_resync (iter);
2795 case GST_ITERATOR_DONE:
2798 case GST_ITERATOR_ERROR:
2799 g_assert_not_reached ();
2803 g_value_unset (&data);
2804 gst_iterator_free (iter);
2806 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2807 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
2808 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
2809 GST_EVENT_TYPE_NAME (event));
2811 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
2812 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
2813 GST_EVENT_TYPE_NAME (event));
2818 switch (gst_iterator_next (iter, &data)) {
2819 case GST_ITERATOR_OK:
2821 GstPad *pad = g_value_get_object (&data);
2823 gst_event_ref (event);
2824 res &= gst_pad_send_event (pad, event);
2825 GST_LOG_OBJECT (pad, "After handling %s event: %d",
2826 GST_EVENT_TYPE_NAME (event), res);
2829 case GST_ITERATOR_RESYNC:
2830 gst_iterator_resync (iter);
2833 case GST_ITERATOR_DONE:
2836 case GST_ITERATOR_ERROR:
2837 g_assert_not_reached ();
2842 g_value_unset (&data);
2843 gst_iterator_free (iter);
2844 gst_event_unref (event);
2849 /* this is the function called by the threadpool. When async elements commit
2850 * their state, this function will attempt to bring the bin to the next state.
2853 gst_bin_continue_func (BinContinueData * data)
2856 GstState current, next, pending;
2857 GstStateChange transition;
2860 pending = data->pending;
2862 GST_DEBUG_OBJECT (bin, "waiting for state lock");
2863 GST_STATE_LOCK (bin);
2865 GST_DEBUG_OBJECT (bin, "doing state continue");
2866 GST_OBJECT_LOCK (bin);
2868 /* if a new state change happened after this thread was scheduled, we return
2870 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
2873 current = GST_STATE (bin);
2874 next = GST_STATE_GET_NEXT (current, pending);
2875 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
2877 GST_STATE_NEXT (bin) = next;
2878 GST_STATE_PENDING (bin) = pending;
2880 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
2881 GST_OBJECT_UNLOCK (bin);
2883 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
2884 "continue state change %s to %s, final %s",
2885 gst_element_state_get_name (current),
2886 gst_element_state_get_name (next), gst_element_state_get_name (pending));
2888 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
2890 GST_STATE_UNLOCK (bin);
2891 GST_DEBUG_OBJECT (bin, "state continue done");
2893 gst_object_unref (bin);
2894 g_slice_free (BinContinueData, data);
2899 GST_OBJECT_UNLOCK (bin);
2900 GST_STATE_UNLOCK (bin);
2901 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
2902 gst_object_unref (bin);
2903 g_slice_free (BinContinueData, data);
2908 static GstBusSyncReply
2909 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
2911 GstBinClass *bclass;
2913 bclass = GST_BIN_GET_CLASS (bin);
2914 if (bclass->handle_message)
2915 bclass->handle_message (bin, message);
2917 gst_message_unref (message);
2919 return GST_BUS_DROP;
2923 bin_push_state_continue (BinContinueData * data)
2930 klass = GST_BIN_GET_CLASS (bin);
2932 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
2933 g_thread_pool_push (klass->pool, data, NULL);
2936 /* an element started an async state change, if we were not busy with a state
2937 * change, we perform a lost state.
2938 * This function is called with the OBJECT lock.
2941 bin_handle_async_start (GstBin * bin)
2943 GstState old_state, new_state;
2945 GstMessage *amessage = NULL;
2947 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
2950 /* get our toplevel state */
2951 toplevel = BIN_IS_TOPLEVEL (bin);
2953 /* prepare an ASYNC_START message, we always post the start message even if we
2954 * are busy with a state change or when we are NO_PREROLL. */
2956 /* non toplevel bin, prepare async-start for the parent */
2957 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
2959 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
2962 /* async starts are ignored when we are NO_PREROLL */
2963 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
2964 goto was_no_preroll;
2966 old_state = GST_STATE (bin);
2968 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
2969 * PLAYING after optionally redistributing the base_time. */
2970 if (old_state > GST_STATE_PAUSED)
2971 new_state = GST_STATE_PAUSED;
2973 new_state = old_state;
2975 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2976 "lost state of %s, new %s", gst_element_state_get_name (old_state),
2977 gst_element_state_get_name (new_state));
2979 GST_STATE (bin) = new_state;
2980 GST_STATE_NEXT (bin) = new_state;
2981 GST_STATE_PENDING (bin) = new_state;
2982 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
2983 GST_OBJECT_UNLOCK (bin);
2986 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
2991 /* post our ASYNC_START. */
2992 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
2993 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
2995 GST_OBJECT_LOCK (bin);
3001 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3006 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3007 GST_OBJECT_UNLOCK (bin);
3012 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3013 GST_OBJECT_UNLOCK (bin);
3018 /* this function is called when there are no more async elements in the bin. We
3019 * post a state changed message and an ASYNC_DONE message.
3020 * This function is called with the OBJECT lock.
3023 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3024 gboolean flag_pending, GstClockTime running_time)
3026 GstState current, pending, target;
3027 GstStateChangeReturn old_ret;
3028 GstState old_state, old_next;
3029 gboolean toplevel, state_changed = FALSE;
3030 GstMessage *amessage = NULL;
3031 BinContinueData *cont = NULL;
3033 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3036 pending = GST_STATE_PENDING (bin);
3041 /* check if there is something to commit */
3042 if (pending == GST_STATE_VOID_PENDING)
3043 goto nothing_pending;
3045 old_ret = GST_STATE_RETURN (bin);
3046 GST_STATE_RETURN (bin) = ret;
3048 /* move to the next target state */
3049 target = GST_STATE_TARGET (bin);
3050 pending = GST_STATE_PENDING (bin) = target;
3052 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3054 old_state = GST_STATE (bin);
3055 /* this is the state we should go to next */
3056 old_next = GST_STATE_NEXT (bin);
3058 if (old_next != GST_STATE_PLAYING) {
3059 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3060 "committing state from %s to %s, old pending %s",
3061 gst_element_state_get_name (old_state),
3062 gst_element_state_get_name (old_next),
3063 gst_element_state_get_name (pending));
3065 /* update current state */
3066 current = GST_STATE (bin) = old_next;
3068 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3069 "setting state from %s to %s, pending %s",
3070 gst_element_state_get_name (old_state),
3071 gst_element_state_get_name (old_state),
3072 gst_element_state_get_name (pending));
3073 current = old_state;
3076 /* get our toplevel state */
3077 toplevel = BIN_IS_TOPLEVEL (bin);
3079 /* see if we reached the final state. If we are not toplevel, we also have to
3080 * stop here, the parent will continue our state. */
3081 if ((pending == current) || !toplevel) {
3082 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3083 "completed state change, pending VOID");
3085 /* mark VOID pending */
3086 pending = GST_STATE_VOID_PENDING;
3087 GST_STATE_PENDING (bin) = pending;
3088 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3090 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3091 "continue state change, pending %s",
3092 gst_element_state_get_name (pending));
3094 cont = g_slice_new (BinContinueData);
3096 /* ref to the bin */
3097 cont->bin = gst_object_ref (bin);
3098 /* cookie to detect concurrent state change */
3099 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3100 /* pending target state */
3101 cont->pending = pending;
3103 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3104 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3107 if (old_next != GST_STATE_PLAYING) {
3108 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3109 state_changed = TRUE;
3112 GST_OBJECT_UNLOCK (bin);
3114 if (state_changed) {
3115 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3119 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3120 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3121 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3124 GST_OBJECT_LOCK (bin);
3126 /* toplevel, start continue state */
3127 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3128 bin_push_state_continue (cont);
3130 GST_DEBUG_OBJECT (bin, "state change complete");
3131 GST_STATE_BROADCAST (bin);
3137 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3142 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3143 /* if we were busy with a state change and we are requested to flag a
3144 * pending async done, we do so here */
3146 bin->priv->pending_async_done = TRUE;
3151 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3157 bin_do_eos (GstBin * bin)
3162 GST_OBJECT_LOCK (bin);
3163 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3164 * we forward the EOS message to the parent bin or application
3166 eos = GST_STATE (bin) == GST_STATE_PLAYING
3167 && GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING
3168 && is_eos (bin, &seqnum);
3169 GST_OBJECT_UNLOCK (bin);
3172 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3174 GstMessage *tmessage;
3176 /* Clear out any further messages, and reset posted_eos so we can
3177 detect any new EOS that happens (eg, after a seek). Since all
3178 sinks have now posted an EOS, there will be no further EOS events
3179 seen unless there is a new logical EOS */
3180 GST_OBJECT_LOCK (bin);
3181 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3182 bin->priv->posted_eos = FALSE;
3183 GST_OBJECT_UNLOCK (bin);
3185 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3186 gst_message_set_seqnum (tmessage, seqnum);
3187 GST_DEBUG_OBJECT (bin,
3188 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3189 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3194 bin_do_stream_start (GstBin * bin)
3197 gboolean stream_start;
3199 GST_OBJECT_LOCK (bin);
3200 /* If all sinks are STREAM_START we forward the STREAM_START message
3201 * to the parent bin or application
3203 stream_start = is_stream_start (bin, &seqnum);
3204 GST_OBJECT_UNLOCK (bin);
3207 GstMessage *tmessage;
3209 GST_OBJECT_LOCK (bin);
3210 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3211 GST_OBJECT_UNLOCK (bin);
3213 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3214 gst_message_set_seqnum (tmessage, seqnum);
3215 GST_DEBUG_OBJECT (bin,
3216 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3218 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3222 /* must be called with the object lock. This function releases the lock to post
3225 bin_do_message_forward (GstBin * bin, GstMessage * message)
3227 if (bin->priv->message_forward) {
3228 GstMessage *forwarded;
3230 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3231 GST_MESSAGE_TYPE_NAME (message));
3232 GST_OBJECT_UNLOCK (bin);
3234 /* we need to convert these messages to element messages so that our parent
3235 * bin can easily ignore them and so that the application can easily
3236 * distinguish between the internally forwarded and the real messages. */
3237 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3238 gst_structure_new ("GstBinForwarded",
3239 "message", GST_TYPE_MESSAGE, message, NULL));
3241 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3243 GST_OBJECT_LOCK (bin);
3247 /* handle child messages:
3249 * This method is called synchronously when a child posts a message on
3252 * GST_MESSAGE_EOS: This message is only posted by sinks
3253 * in the PLAYING state. If all sinks posted the EOS message, post
3256 * GST_MESSAGE_STATE_DIRTY: Deprecated
3258 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3259 * element posts segment_start twice, only the last message is kept.
3261 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3262 * with the segment_done message. If there are no more segment_start
3263 * messages, post segment_done message upwards.
3265 * GST_MESSAGE_DURATION_CHANGED: clear any cached durations.
3266 * Whenever someone performs a duration query on the bin, we store the
3267 * result so we can answer it quicker the next time. Any element that
3268 * changes its duration marks our cached values invalid.
3269 * This message is also posted upwards. This is currently disabled
3270 * because too many elements don't post DURATION_CHANGED messages when
3271 * the duration changes.
3273 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3274 * can no longer provide a clock. The default bin behaviour is to
3275 * check if the lost clock was the one provided by the bin. If so and
3276 * we are currently in the PLAYING state, we forward the message to
3278 * This message is also generated when we remove a clock provider from
3279 * a bin. If this message is received by the application, it should
3280 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3281 * and a new base_time distribution.
3283 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3284 * can provide a clock. This mostly happens when we add a new clock
3285 * provider to the bin. The default behaviour of the bin is to mark the
3286 * currently selected clock as dirty, which will perform a clock
3287 * recalculation the next time we are asked to provide a clock.
3288 * This message is never sent to the application but is forwarded to
3291 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3292 * the state of the element and the fact that the element will need a
3293 * new base_time. This message is not forwarded to the application.
3295 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3296 * element when it posted ASYNC_START. If all elements are done, post a
3297 * ASYNC_DONE message to the parent.
3299 * OTHER: post upwards.
3302 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3305 GstMessageType type;
3306 GstMessage *tmessage;
3309 src = GST_MESSAGE_SRC (message);
3310 type = GST_MESSAGE_TYPE (message);
3312 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3313 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3314 GST_MESSAGE_TYPE_NAME (message));
3317 case GST_MESSAGE_ERROR:
3319 GST_OBJECT_LOCK (bin);
3321 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3322 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3323 GST_STATE_BROADCAST (bin);
3324 GST_OBJECT_UNLOCK (bin);
3328 case GST_MESSAGE_EOS:
3331 /* collect all eos messages from the children */
3332 GST_OBJECT_LOCK (bin);
3333 bin_do_message_forward (bin, message);
3334 /* ref message for future use */
3335 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3336 GST_OBJECT_UNLOCK (bin);
3341 case GST_MESSAGE_STREAM_START:
3344 /* collect all stream_start messages from the children */
3345 GST_OBJECT_LOCK (bin);
3346 /* ref message for future use */
3347 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3348 GST_OBJECT_UNLOCK (bin);
3350 bin_do_stream_start (bin);
3353 case GST_MESSAGE_STATE_DIRTY:
3355 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3358 gst_message_unref (message);
3361 case GST_MESSAGE_SEGMENT_START:{
3362 gboolean post = FALSE;
3366 gst_message_parse_segment_start (message, &format, &position);
3367 seqnum = gst_message_get_seqnum (message);
3369 GST_OBJECT_LOCK (bin);
3370 bin_do_message_forward (bin, message);
3371 /* if this is the first segment-start, post to parent but not to the
3373 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3374 (GST_OBJECT_PARENT (bin) != NULL)) {
3377 /* replace any previous segment_start message from this source
3378 * with the new segment start message */
3379 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3380 GST_OBJECT_UNLOCK (bin);
3382 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3384 gst_message_set_seqnum (tmessage, seqnum);
3386 /* post segment start with initial format and position. */
3387 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3389 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3393 case GST_MESSAGE_SEGMENT_DONE:
3395 gboolean post = FALSE;
3399 gst_message_parse_segment_done (message, &format, &position);
3400 seqnum = gst_message_get_seqnum (message);
3402 GST_OBJECT_LOCK (bin);
3403 bin_do_message_forward (bin, message);
3404 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3405 /* if there are no more segment_start messages, everybody posted
3406 * a segment_done and we can post one on the bus. */
3408 /* we don't care who still has a pending segment start */
3409 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3412 /* remove all old segment_done messages */
3413 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3415 GST_OBJECT_UNLOCK (bin);
3417 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3419 gst_message_set_seqnum (tmessage, seqnum);
3421 /* post segment done with latest format and position. */
3422 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3424 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3428 case GST_MESSAGE_DURATION_CHANGED:
3430 /* FIXME: remove all cached durations, next time somebody asks
3431 * for duration, we will recalculate. */
3433 GST_OBJECT_LOCK (bin);
3434 bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION_CHANGED);
3435 GST_OBJECT_UNLOCK (bin);
3439 case GST_MESSAGE_CLOCK_LOST:
3441 GstClock **provided_clock_p;
3442 GstElement **clock_provider_p;
3443 gboolean playing, toplevel, provided, forward;
3446 gst_message_parse_clock_lost (message, &clock);
3448 GST_OBJECT_LOCK (bin);
3449 bin->clock_dirty = TRUE;
3450 /* if we lost the clock that we provided, post to parent but
3451 * only if we are not a top-level bin or PLAYING.
3452 * The reason for this is that applications should be able
3453 * to PAUSE/PLAY if they receive this message without worrying
3454 * about the state of the pipeline. */
3455 provided = (clock == bin->provided_clock);
3456 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3457 toplevel = GST_OBJECT_PARENT (bin) == NULL;
3458 forward = provided && (playing || !toplevel);
3460 GST_DEBUG_OBJECT (bin,
3461 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3462 bin->provided_clock, bin->clock_provider);
3463 provided_clock_p = &bin->provided_clock;
3464 clock_provider_p = &bin->clock_provider;
3465 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3466 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3468 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3469 provided, playing, forward);
3470 GST_OBJECT_UNLOCK (bin);
3476 gst_message_unref (message);
3479 case GST_MESSAGE_CLOCK_PROVIDE:
3483 GST_OBJECT_LOCK (bin);
3484 bin->clock_dirty = TRUE;
3485 /* a new clock is available, post to parent but not
3486 * to the application */
3487 forward = GST_OBJECT_PARENT (bin) != NULL;
3488 GST_OBJECT_UNLOCK (bin);
3494 gst_message_unref (message);
3497 case GST_MESSAGE_ASYNC_START:
3501 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3502 src ? GST_OBJECT_NAME (src) : "(NULL)");
3504 GST_OBJECT_LOCK (bin);
3505 bin_do_message_forward (bin, message);
3507 /* we ignore the message if we are going to <= READY */
3508 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3509 goto ignore_start_message;
3511 /* takes ownership of the message */
3512 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3514 bin_handle_async_start (bin);
3515 GST_OBJECT_UNLOCK (bin);
3518 ignore_start_message:
3520 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3521 gst_element_state_get_name (target));
3522 GST_OBJECT_UNLOCK (bin);
3523 gst_message_unref (message);
3527 case GST_MESSAGE_ASYNC_DONE:
3529 GstClockTime running_time;
3532 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3533 src ? GST_OBJECT_NAME (src) : "(NULL)");
3535 gst_message_parse_async_done (message, &running_time);
3537 GST_OBJECT_LOCK (bin);
3538 bin_do_message_forward (bin, message);
3540 /* ignore messages if we are shutting down */
3541 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3542 goto ignore_done_message;
3544 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3545 /* if there are no more ASYNC_START messages, everybody posted
3546 * a ASYNC_DONE and we can post one on the bus. When checking, we
3547 * don't care who still has a pending ASYNC_START */
3548 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3549 /* nothing found, remove all old ASYNC_DONE messages */
3550 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3552 GST_DEBUG_OBJECT (bin, "async elements commited");
3553 /* when we get an async done message when a state change was busy, we
3554 * need to set the pending_done flag so that at the end of the state
3555 * change we can see if we need to verify pending async elements, hence
3556 * the TRUE argument here. */
3557 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3560 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3562 GST_OBJECT_UNLOCK (bin);
3565 ignore_done_message:
3567 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3568 gst_element_state_get_name (target));
3569 GST_OBJECT_UNLOCK (bin);
3570 gst_message_unref (message);
3574 case GST_MESSAGE_STRUCTURE_CHANGE:
3578 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3580 GST_OBJECT_LOCK (bin);
3582 /* while the pad is busy, avoid following it when doing state changes.
3583 * Don't update the cookie yet, we will do that after the structure
3584 * change finished and we are ready to inspect the new updated
3586 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3589 /* a pad link/unlink ended, signal the state change iterator that we
3590 * need to resync by updating the structure_cookie. */
3591 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3592 GST_MESSAGE_STRUCTURE_CHANGE);
3593 if (!GST_BIN_IS_NO_RESYNC (bin))
3594 bin->priv->structure_cookie++;
3596 GST_OBJECT_UNLOCK (bin);
3599 gst_message_unref (message);
3610 /* Send all other messages upward */
3611 GST_DEBUG_OBJECT (bin, "posting message upward");
3612 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
3617 /* generic struct passed to all query fold methods */
3626 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
3627 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
3629 /* for duration/position we collect all durations/positions and take
3630 * the MAX of all valid results */
3632 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
3640 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3642 gboolean res = FALSE;
3643 GstObject *item = g_value_get_object (vitem);
3644 if (GST_IS_PAD (item))
3645 res = gst_pad_query (GST_PAD (item), fold->query);
3647 res = gst_element_query (GST_ELEMENT (item), fold->query);
3652 g_value_set_boolean (ret, TRUE);
3654 gst_query_parse_duration (fold->query, NULL, &duration);
3656 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
3658 if (duration == -1) {
3659 /* duration query succeeded, but duration is unknown */
3664 if (duration > fold->max)
3665 fold->max = duration;
3672 bin_query_duration_done (GstBin * bin, QueryFold * fold)
3676 gst_query_parse_duration (fold->query, &format, NULL);
3677 /* store max in query result */
3678 gst_query_set_duration (fold->query, format, fold->max);
3680 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
3682 /* FIXME: re-implement duration caching */
3685 GST_OBJECT_LOCK (bin);
3686 bin->messages = g_list_prepend (bin->messages,
3687 gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
3688 GST_OBJECT_UNLOCK (bin);
3693 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3695 gboolean res = FALSE;
3696 GstObject *item = g_value_get_object (vitem);
3697 if (GST_IS_PAD (item))
3698 res = gst_pad_query (GST_PAD (item), fold->query);
3700 res = gst_element_query (GST_ELEMENT (item), fold->query);
3705 g_value_set_boolean (ret, TRUE);
3707 gst_query_parse_position (fold->query, NULL, &position);
3709 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
3711 if (position > fold->max)
3712 fold->max = position;
3719 bin_query_position_done (GstBin * bin, QueryFold * fold)
3723 gst_query_parse_position (fold->query, &format, NULL);
3724 /* store max in query result */
3725 gst_query_set_position (fold->query, format, fold->max);
3727 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
3731 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3733 gboolean res = FALSE;
3734 GstObject *item = g_value_get_object (vitem);
3735 if (GST_IS_PAD (item))
3736 res = gst_pad_query (GST_PAD (item), fold->query);
3738 res = gst_element_query (GST_ELEMENT (item), fold->query);
3740 GstClockTime min, max;
3743 gst_query_parse_latency (fold->query, &live, &min, &max);
3745 GST_DEBUG_OBJECT (item,
3746 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3747 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
3749 /* for the combined latency we collect the MAX of all min latencies and
3750 * the MIN of all max latencies */
3752 if (min > fold->min)
3754 if (fold->max == -1)
3756 else if (max < fold->max)
3758 if (fold->live == FALSE)
3762 g_value_set_boolean (ret, FALSE);
3763 GST_DEBUG_OBJECT (item, "failed query");
3770 bin_query_latency_done (GstBin * bin, QueryFold * fold)
3772 /* store max in query result */
3773 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
3775 GST_DEBUG_OBJECT (bin,
3776 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3777 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
3781 /* generic fold, return first valid result */
3783 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3785 gboolean res = FALSE;
3786 GstObject *item = g_value_get_object (vitem);
3787 if (GST_IS_PAD (item))
3788 res = gst_pad_query (GST_PAD (item), fold->query);
3790 res = gst_element_query (GST_ELEMENT (item), fold->query);
3792 g_value_set_boolean (ret, TRUE);
3793 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
3796 /* and stop as soon as we have a valid result */
3800 /* Perform a query iteration for the given bin. The query is stored in
3801 * QueryFold and iter should be either a GstPad iterator or a
3802 * GstElement iterator. */
3804 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
3805 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
3806 QueryFold fold_data, gboolean default_return)
3808 gboolean res = default_return;
3810 /* set the result of the query to FALSE initially */
3811 g_value_init (&ret, G_TYPE_BOOLEAN);
3812 g_value_set_boolean (&ret, res);
3815 GstIteratorResult ires;
3817 ires = gst_iterator_fold (iter, fold_func, &ret, &fold_data);
3820 case GST_ITERATOR_RESYNC:
3821 gst_iterator_resync (iter);
3823 fold_init (bin, &fold_data);
3824 g_value_set_boolean (&ret, res);
3826 case GST_ITERATOR_OK:
3827 case GST_ITERATOR_DONE:
3828 res = g_value_get_boolean (&ret);
3829 if (fold_done != NULL && res)
3830 fold_done (bin, &fold_data);
3842 gst_bin_query (GstElement * element, GstQuery * query)
3844 GstBin *bin = GST_BIN_CAST (element);
3846 gboolean default_return = FALSE;
3847 gboolean res = FALSE;
3848 gboolean src_pads_query_result = FALSE;
3849 GstIteratorFoldFunction fold_func;
3850 QueryInitFunction fold_init = NULL;
3851 QueryDoneFunction fold_done = NULL;
3852 QueryFold fold_data;
3854 switch (GST_QUERY_TYPE (query)) {
3855 case GST_QUERY_DURATION:
3857 /* FIXME: implement duration caching in GstBin again */
3862 gst_query_parse_duration (query, &qformat, NULL);
3864 /* find cached duration query */
3865 GST_OBJECT_LOCK (bin);
3866 for (cached = bin->messages; cached; cached = g_list_next (cached)) {
3867 GstMessage *message = (GstMessage *) cached->data;
3869 if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION_CHANGED &&
3870 GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
3874 gst_message_parse_duration (message, &format, &duration);
3876 /* if cached same format, copy duration in query result */
3877 if (format == qformat) {
3878 GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
3880 GST_OBJECT_UNLOCK (bin);
3882 gst_query_set_duration (query, qformat, duration);
3888 GST_OBJECT_UNLOCK (bin);
3890 GST_FIXME ("implement duration caching in GstBin again");
3892 /* no cached value found, iterate and collect durations */
3893 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
3894 fold_init = bin_query_min_max_init;
3895 fold_done = bin_query_duration_done;
3898 case GST_QUERY_POSITION:
3900 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
3901 fold_init = bin_query_min_max_init;
3902 fold_done = bin_query_position_done;
3905 case GST_QUERY_LATENCY:
3907 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
3908 fold_init = bin_query_min_max_init;
3909 fold_done = bin_query_latency_done;
3910 default_return = TRUE;
3914 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
3918 fold_data.query = query;
3920 iter = gst_bin_iterate_sinks (bin);
3921 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
3922 query, GST_QUERY_TYPE_NAME (query));
3925 fold_init (bin, &fold_data);
3928 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, fold_data,
3930 gst_iterator_free (iter);
3933 /* Query the source pads of the element */
3934 iter = gst_element_iterate_src_pads (element);
3935 src_pads_query_result =
3936 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
3937 fold_data, default_return);
3938 gst_iterator_free (iter);
3940 if (src_pads_query_result)
3944 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
3950 set_context (const GValue * item, gpointer user_data)
3952 GstElement *element = g_value_get_object (item);
3954 gst_element_set_context (element, user_data);
3958 gst_bin_set_context (GstElement * element, GstContext * context)
3961 GstIterator *children;
3963 g_return_if_fail (GST_IS_BIN (element));
3965 bin = GST_BIN (element);
3967 children = gst_bin_iterate_elements (bin);
3968 while (gst_iterator_foreach (children, set_context,
3969 context) == GST_ITERATOR_RESYNC);
3970 gst_iterator_free (children);
3974 compare_name (const GValue * velement, const gchar * name)
3977 GstElement *element = g_value_get_object (velement);
3979 GST_OBJECT_LOCK (element);
3980 eq = strcmp (GST_ELEMENT_NAME (element), name);
3981 GST_OBJECT_UNLOCK (element);
3987 * gst_bin_get_by_name:
3989 * @name: the element name to search for
3991 * Gets the element with the given name from a bin. This
3992 * function recurses into child bins.
3994 * Returns NULL if no element with the given name is found in the bin.
3996 * MT safe. Caller owns returned reference.
3998 * Returns: (transfer full): the #GstElement with the given name, or NULL
4001 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4003 GstIterator *children;
4004 GValue result = { 0, };
4005 GstElement *element;
4008 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4010 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4011 GST_ELEMENT_NAME (bin), name);
4013 children = gst_bin_iterate_recurse (bin);
4014 found = gst_iterator_find_custom (children,
4015 (GCompareFunc) compare_name, &result, (gpointer) name);
4016 gst_iterator_free (children);
4019 element = g_value_dup_object (&result);
4020 g_value_unset (&result);
4029 * gst_bin_get_by_name_recurse_up:
4031 * @name: the element name to search for
4033 * Gets the element with the given name from this bin. If the
4034 * element is not found, a recursion is performed on the parent bin.
4037 * - no element with the given name is found in the bin
4039 * MT safe. Caller owns returned reference.
4041 * Returns: (transfer full): the #GstElement with the given name, or NULL
4044 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4048 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4049 g_return_val_if_fail (name != NULL, NULL);
4051 result = gst_bin_get_by_name (bin, name);
4056 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4058 if (GST_IS_BIN (parent)) {
4059 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4061 gst_object_unref (parent);
4069 compare_interface (const GValue * velement, GValue * interface)
4071 GstElement *element = g_value_get_object (velement);
4072 GType interface_type = (GType) g_value_get_pointer (interface);
4075 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4084 * gst_bin_get_by_interface:
4086 * @iface: the #GType of an interface
4088 * Looks for an element inside the bin that implements the given
4089 * interface. If such an element is found, it returns the element.
4090 * You can cast this element to the given interface afterwards. If you want
4091 * all elements that implement the interface, use
4092 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4094 * MT safe. Caller owns returned reference.
4096 * Returns: (transfer full): A #GstElement inside the bin implementing the interface
4099 gst_bin_get_by_interface (GstBin * bin, GType iface)
4101 GstIterator *children;
4102 GValue result = { 0, };
4103 GstElement *element;
4105 GValue viface = { 0, };
4107 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4108 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4110 g_value_init (&viface, G_TYPE_POINTER);
4111 g_value_set_pointer (&viface, (gpointer) iface);
4113 children = gst_bin_iterate_recurse (bin);
4114 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4116 gst_iterator_free (children);
4119 element = g_value_dup_object (&result);
4120 g_value_unset (&result);
4124 g_value_unset (&viface);
4130 * gst_bin_iterate_all_by_interface:
4132 * @iface: the #GType of an interface
4134 * Looks for all elements inside the bin that implements the given
4135 * interface. You can safely cast all returned elements to the given interface.
4136 * The function recurses inside child bins. The iterator will yield a series
4137 * of #GstElement that should be unreffed after use.
4139 * MT safe. Caller owns returned value.
4141 * Returns: (transfer full): a #GstIterator of #GstElement for all elements
4142 * in the bin implementing the given interface, or NULL
4145 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4147 GstIterator *children;
4148 GstIterator *result;
4149 GValue viface = { 0, };
4151 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4152 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4154 g_value_init (&viface, G_TYPE_POINTER);
4155 g_value_set_pointer (&viface, (gpointer) iface);
4157 children = gst_bin_iterate_recurse (bin);
4158 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4161 g_value_unset (&viface);