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.
158 #include "gst_private.h"
160 #include "gstevent.h"
163 #include "gsterror.h"
165 #include "gstutils.h"
166 #include "gstchildproxy.h"
168 GST_DEBUG_CATEGORY_STATIC (bin_debug);
169 #define GST_CAT_DEFAULT bin_debug
171 /* a bin is toplevel if it has no parent or when it is configured to behave like
173 #define BIN_IS_TOPLEVEL(bin) ((GST_OBJECT_PARENT (bin) == NULL) || bin->priv->asynchandling)
175 #define GST_BIN_GET_PRIVATE(obj) \
176 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BIN, GstBinPrivate))
178 struct _GstBinPrivate
180 gboolean asynchandling;
181 /* if we get an ASYNC_DONE message from ourselves, this means that the
182 * subclass will simulate ASYNC behaviour without having ASYNC children. When
183 * such an ASYNC_DONE message is posted while we are doing a state change, we
184 * have to process the message after finishing the state change even when no
185 * child returned GST_STATE_CHANGE_ASYNC. */
186 gboolean pending_async_done;
188 guint32 structure_cookie;
195 /* forward messages from our children */
196 gboolean message_forward;
199 gboolean posted_playing;
208 static void gst_bin_dispose (GObject * object);
210 static void gst_bin_set_property (GObject * object, guint prop_id,
211 const GValue * value, GParamSpec * pspec);
212 static void gst_bin_get_property (GObject * object, guint prop_id,
213 GValue * value, GParamSpec * pspec);
215 static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
216 GstStateChange transition);
217 static gboolean gst_bin_post_message (GstElement * element, GstMessage * msg);
218 static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
219 GstState * state, GstState * pending, GstClockTime timeout);
220 static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
221 gboolean flag_pending, GstClockTime running_time);
222 static void bin_handle_async_start (GstBin * bin);
223 static void bin_push_state_continue (GstBin * bin, BinContinueData * data);
224 static void bin_do_eos (GstBin * bin);
226 static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
227 static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
228 static void gst_bin_deep_element_added_func (GstBin * bin, GstBin * sub_bin,
229 GstElement * element);
230 static void gst_bin_deep_element_removed_func (GstBin * bin, GstBin * sub_bin,
231 GstElement * element);
232 static void gst_bin_update_context (GstBin * bin, GstContext * context);
233 static void gst_bin_update_context_unlocked (GstBin * bin,
234 GstContext * context);
237 static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
238 static GstIndex *gst_bin_get_index_func (GstElement * element);
241 static GstClock *gst_bin_provide_clock_func (GstElement * element);
242 static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
244 static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
245 static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
246 static GstBusSyncReply bin_bus_handler (GstBus * bus,
247 GstMessage * message, GstBin * bin);
248 static gboolean gst_bin_query (GstElement * element, GstQuery * query);
249 static void gst_bin_set_context (GstElement * element, GstContext * context);
251 static gboolean gst_bin_do_latency_func (GstBin * bin);
253 static void bin_remove_messages (GstBin * bin, GstObject * src,
254 GstMessageType types);
255 static void gst_bin_continue_func (GstBin * bin, BinContinueData * data);
256 static gint bin_element_is_sink (GstElement * child, GstBin * bin);
257 static gint bin_element_is_src (GstElement * child, GstBin * bin);
259 static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
261 /* Bin signals and properties */
268 DEEP_ELEMENT_REMOVED,
272 #define DEFAULT_ASYNC_HANDLING FALSE
273 #define DEFAULT_MESSAGE_FORWARD FALSE
279 PROP_MESSAGE_FORWARD,
283 static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
285 static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
289 static const GInterfaceInfo iface_info = { \
290 gst_bin_child_proxy_init, \
294 g_type_add_interface_static (g_define_type_id, GST_TYPE_CHILD_PROXY, &iface_info); \
296 GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
297 "debugging info for the 'bin' container element"); \
301 #define gst_bin_parent_class parent_class
302 G_DEFINE_TYPE_WITH_CODE (GstBin, gst_bin, GST_TYPE_ELEMENT, _do_init);
305 gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
311 bin = GST_BIN_CAST (child_proxy);
313 GST_OBJECT_LOCK (bin);
314 if ((res = g_list_nth_data (bin->children, index)))
315 gst_object_ref (res);
316 GST_OBJECT_UNLOCK (bin);
318 return (GObject *) res;
322 gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
327 bin = GST_BIN_CAST (child_proxy);
329 GST_OBJECT_LOCK (bin);
330 num = bin->numchildren;
331 GST_OBJECT_UNLOCK (bin);
337 gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
339 GstChildProxyInterface *iface = g_iface;
341 iface->get_children_count = gst_bin_child_proxy_get_children_count;
342 iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
346 _gst_boolean_accumulator (GSignalInvocationHint * ihint,
347 GValue * return_accu, const GValue * handler_return, gpointer dummy)
351 myboolean = g_value_get_boolean (handler_return);
352 if (!(ihint->run_type & G_SIGNAL_RUN_CLEANUP))
353 g_value_set_boolean (return_accu, myboolean);
355 GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
362 gst_bin_class_init (GstBinClass * klass)
364 GObjectClass *gobject_class;
365 GstElementClass *gstelement_class;
367 gobject_class = (GObjectClass *) klass;
368 gstelement_class = (GstElementClass *) klass;
370 g_type_class_add_private (klass, sizeof (GstBinPrivate));
372 gobject_class->set_property = gst_bin_set_property;
373 gobject_class->get_property = gst_bin_get_property;
376 * GstBin:async-handling:
378 * If set to %TRUE, the bin will handle asynchronous state changes.
379 * This should be used only if the bin subclass is modifying the state
380 * of its children on its own.
382 g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
383 g_param_spec_boolean ("async-handling", "Async Handling",
384 "The bin will handle Asynchronous state changes",
385 DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
388 * GstBin::element-added:
390 * @element: the #GstElement that was added to the bin
392 * Will be emitted after the element was added to the bin.
394 gst_bin_signals[ELEMENT_ADDED] =
395 g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
396 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
397 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
399 * GstBin::element-removed:
401 * @element: the #GstElement that was removed from the bin
403 * Will be emitted after the element was removed from the bin.
405 gst_bin_signals[ELEMENT_REMOVED] =
406 g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
407 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
408 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
410 * GstBin::deep-element-added:
412 * @sub_bin: the #GstBin the element was added to
413 * @element: the #GstElement that was added to @sub_bin
415 * Will be emitted after the element was added to sub_bin.
419 gst_bin_signals[DEEP_ELEMENT_ADDED] =
420 g_signal_new ("deep-element-added", G_TYPE_FROM_CLASS (klass),
421 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, deep_element_added),
422 NULL, NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 2, GST_TYPE_BIN,
425 * GstBin::deep-element-removed:
427 * @sub_bin: the #GstBin the element was removed from
428 * @element: the #GstElement that was removed from @sub_bin
430 * Will be emitted after the element was removed from sub_bin.
434 gst_bin_signals[DEEP_ELEMENT_REMOVED] =
435 g_signal_new ("deep-element-removed", G_TYPE_FROM_CLASS (klass),
436 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, deep_element_removed),
437 NULL, NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 2, GST_TYPE_BIN,
440 * GstBin::do-latency:
443 * Will be emitted when the bin needs to perform latency calculations. This
444 * signal is only emitted for toplevel bins or when async-handling is
447 * Only one signal handler is invoked. If no signals are connected, the
448 * default handler is invoked, which will query and distribute the lowest
449 * possible latency to all sinks.
451 * Connect to this signal if the default latency calculations are not
452 * sufficient, like when you need different latencies for different sinks in
455 gst_bin_signals[DO_LATENCY] =
456 g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
457 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
458 _gst_boolean_accumulator, NULL, g_cclosure_marshal_generic,
459 G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
462 * GstBin:message-forward:
464 * Forward all children messages, even those that would normally be filtered by
465 * the bin. This can be interesting when one wants to be notified of the EOS
466 * state of individual elements, for example.
468 * The messages are converted to an ELEMENT message with the bin as the
469 * source. The structure of the message is named 'GstBinForwarded' and contains
470 * a field named 'message' of type GST_TYPE_MESSAGE that contains the original
473 g_object_class_install_property (gobject_class, PROP_MESSAGE_FORWARD,
474 g_param_spec_boolean ("message-forward", "Message Forward",
475 "Forwards all children messages",
476 DEFAULT_MESSAGE_FORWARD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
478 gobject_class->dispose = gst_bin_dispose;
480 gst_element_class_set_static_metadata (gstelement_class, "Generic bin",
482 "Simple container object",
483 "Erik Walthinsen <omega@cse.ogi.edu>,"
484 "Wim Taymans <wim.taymans@gmail.com>");
486 gstelement_class->change_state =
487 GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
488 gstelement_class->post_message = GST_DEBUG_FUNCPTR (gst_bin_post_message);
489 gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
491 gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
492 gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
494 gstelement_class->provide_clock =
495 GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
496 gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
498 gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
499 gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
500 gstelement_class->set_context = GST_DEBUG_FUNCPTR (gst_bin_set_context);
502 klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
503 klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
504 klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
506 klass->deep_element_added = gst_bin_deep_element_added_func;
507 klass->deep_element_removed = gst_bin_deep_element_removed_func;
509 klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
513 gst_bin_init (GstBin * bin)
517 bin->numchildren = 0;
518 bin->children = NULL;
519 bin->children_cookie = 0;
520 bin->messages = NULL;
521 bin->provided_clock = NULL;
522 bin->clock_dirty = FALSE;
524 /* Set up a bus for listening to child elements */
525 bus = g_object_new (GST_TYPE_BUS, "enable-async", FALSE, NULL);
526 bin->child_bus = bus;
527 GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
529 gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin,
532 bin->priv = GST_BIN_GET_PRIVATE (bin);
533 bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
534 bin->priv->structure_cookie = 0;
535 bin->priv->message_forward = DEFAULT_MESSAGE_FORWARD;
539 gst_bin_dispose (GObject * object)
541 GstBin *bin = GST_BIN_CAST (object);
542 GstBus **child_bus_p = &bin->child_bus;
543 GstClock **provided_clock_p = &bin->provided_clock;
544 GstElement **clock_provider_p = &bin->clock_provider;
546 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "%p dispose", object);
548 GST_OBJECT_LOCK (object);
549 gst_object_replace ((GstObject **) child_bus_p, NULL);
550 gst_object_replace ((GstObject **) provided_clock_p, NULL);
551 gst_object_replace ((GstObject **) clock_provider_p, NULL);
552 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
553 GST_OBJECT_UNLOCK (object);
555 while (bin->children) {
556 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
558 if (G_UNLIKELY (bin->children != NULL)) {
559 g_critical ("could not remove elements from bin '%s'",
560 GST_STR_NULL (GST_OBJECT_NAME (object)));
563 G_OBJECT_CLASS (parent_class)->dispose (object);
568 * @name: (allow-none): the name of the new bin
570 * Creates a new bin with the given name.
572 * Returns: (transfer floating): a new #GstBin
575 gst_bin_new (const gchar * name)
577 return gst_element_factory_make ("bin", name);
581 gst_bin_set_property (GObject * object, guint prop_id,
582 const GValue * value, GParamSpec * pspec)
586 gstbin = GST_BIN_CAST (object);
589 case PROP_ASYNC_HANDLING:
590 GST_OBJECT_LOCK (gstbin);
591 gstbin->priv->asynchandling = g_value_get_boolean (value);
592 GST_OBJECT_UNLOCK (gstbin);
594 case PROP_MESSAGE_FORWARD:
595 GST_OBJECT_LOCK (gstbin);
596 gstbin->priv->message_forward = g_value_get_boolean (value);
597 GST_OBJECT_UNLOCK (gstbin);
600 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
606 gst_bin_get_property (GObject * object, guint prop_id,
607 GValue * value, GParamSpec * pspec)
611 gstbin = GST_BIN_CAST (object);
614 case PROP_ASYNC_HANDLING:
615 GST_OBJECT_LOCK (gstbin);
616 g_value_set_boolean (value, gstbin->priv->asynchandling);
617 GST_OBJECT_UNLOCK (gstbin);
619 case PROP_MESSAGE_FORWARD:
620 GST_OBJECT_LOCK (gstbin);
621 g_value_set_boolean (value, gstbin->priv->message_forward);
622 GST_OBJECT_UNLOCK (gstbin);
625 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
631 /* return the cached index */
633 gst_bin_get_index_func (GstElement * element)
638 bin = GST_BIN_CAST (element);
640 GST_OBJECT_LOCK (bin);
641 if ((result = bin->priv->index))
642 gst_object_ref (result);
643 GST_OBJECT_UNLOCK (bin);
648 /* set the index on all elements in this bin
653 gst_bin_set_index_func (GstElement * element, GstIndex * index)
659 GValue data = { 0, };
661 bin = GST_BIN_CAST (element);
663 GST_OBJECT_LOCK (bin);
664 old = bin->priv->index;
665 if (G_UNLIKELY (old == index))
668 gst_object_ref (index);
669 bin->priv->index = index;
670 GST_OBJECT_UNLOCK (bin);
673 gst_object_unref (old);
675 it = gst_bin_iterate_elements (bin);
677 /* set the index on all elements in the bin */
680 switch (gst_iterator_next (it, &data)) {
681 case GST_ITERATOR_OK:
683 GstElement *child = g_value_get_object (&data);
685 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
686 GST_ELEMENT_NAME (child));
687 gst_element_set_index (child, index);
689 g_value_reset (&data);
692 case GST_ITERATOR_RESYNC:
693 GST_DEBUG_OBJECT (bin, "iterator doing resync");
694 gst_iterator_resync (it);
697 case GST_ITERATOR_DONE:
698 GST_DEBUG_OBJECT (bin, "iterator done");
703 g_value_unset (&data);
704 gst_iterator_free (it);
709 GST_DEBUG_OBJECT (bin, "index was already set");
710 GST_OBJECT_UNLOCK (bin);
716 /* set the clock on all elements in this bin
721 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
727 GValue data = { 0, };
729 bin = GST_BIN_CAST (element);
731 it = gst_bin_iterate_elements (bin);
735 switch (gst_iterator_next (it, &data)) {
736 case GST_ITERATOR_OK:
738 GstElement *child = g_value_get_object (&data);
740 res &= gst_element_set_clock (child, clock);
742 g_value_reset (&data);
745 case GST_ITERATOR_RESYNC:
746 GST_DEBUG_OBJECT (bin, "iterator doing resync");
747 gst_iterator_resync (it);
751 case GST_ITERATOR_DONE:
752 GST_DEBUG_OBJECT (bin, "iterator done");
757 g_value_unset (&data);
758 gst_iterator_free (it);
761 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
766 /* get the clock for this bin by asking all of the children in this bin
768 * The ref of the returned clock in increased so unref after usage.
770 * We loop the elements in state order and pick the last clock we can
771 * get. This makes sure we get a clock from the source.
776 gst_bin_provide_clock_func (GstElement * element)
778 GstClock *result = NULL;
779 GstElement *provider = NULL;
784 GstClock **provided_clock_p;
785 GstElement **clock_provider_p;
787 bin = GST_BIN_CAST (element);
789 GST_OBJECT_LOCK (bin);
790 if (!bin->clock_dirty)
793 GST_DEBUG_OBJECT (bin, "finding new clock");
795 it = gst_bin_sort_iterator_new (bin);
796 GST_OBJECT_UNLOCK (bin);
800 switch (gst_iterator_next (it, &val)) {
801 case GST_ITERATOR_OK:
803 GstElement *child = g_value_get_object (&val);
806 clock = gst_element_provide_clock (child);
808 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
809 clock, GST_ELEMENT_NAME (child));
811 gst_object_unref (result);
812 gst_object_unref (provider);
815 provider = gst_object_ref (child);
818 g_value_reset (&val);
821 case GST_ITERATOR_RESYNC:
822 gst_iterator_resync (it);
825 case GST_ITERATOR_DONE:
830 g_value_unset (&val);
831 gst_iterator_free (it);
833 GST_OBJECT_LOCK (bin);
834 if (!bin->clock_dirty) {
836 gst_object_unref (provider);
838 gst_object_unref (result);
844 provided_clock_p = &bin->provided_clock;
845 clock_provider_p = &bin->clock_provider;
846 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
847 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
848 bin->clock_dirty = FALSE;
849 GST_DEBUG_OBJECT (bin,
850 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
852 /* Provider is not being returned to caller, just the result */
854 gst_object_unref (provider);
855 GST_OBJECT_UNLOCK (bin);
861 if ((result = bin->provided_clock))
862 gst_object_ref (result);
863 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
864 GST_OBJECT_UNLOCK (bin);
871 * functions for manipulating cached messages
876 GstMessageType types;
879 /* check if a message is of given src and type */
881 message_check (GstMessage * message, MessageFind * target)
886 eq &= GST_MESSAGE_SRC (message) == target->src;
888 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
889 GST_LOG ("looking at message %p: %d", message, eq);
895 find_message (GstBin * bin, GstObject * src, GstMessageType types)
903 result = g_list_find_custom (bin->messages, &find,
904 (GCompareFunc) message_check);
907 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
908 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
911 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
912 #ifndef GST_DISABLE_GST_DEBUG
916 for (i = 0; i < 32; i++)
917 if (types & (1U << i))
918 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1U << i));
926 /* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
929 * A message that is cached and has the same SRC and type is replaced
930 * by the given message.
933 bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
939 if ((src = GST_MESSAGE_SRC (message))) {
940 /* first find the previous message posted by this element */
941 if ((previous = find_message (bin, src, types))) {
942 GstMessage *previous_msg;
944 /* if we found a previous message, replace it */
945 previous_msg = previous->data;
946 previous->data = message;
948 GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
949 GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
950 GST_MESSAGE_TYPE_NAME (message));
952 gst_message_unref (previous_msg);
954 /* keep new message */
955 bin->messages = g_list_prepend (bin->messages, message);
957 GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
958 message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
961 GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
962 GST_MESSAGE_TYPE_NAME (message));
964 gst_message_unref (message);
969 /* with LOCK. Remove all messages of given types */
971 bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
979 for (walk = bin->messages; walk; walk = next) {
980 GstMessage *message = (GstMessage *) walk->data;
982 next = g_list_next (walk);
984 if (message_check (message, &find) == 0) {
985 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
986 "deleting message %p of types 0x%08x", message, types);
987 bin->messages = g_list_delete_link (bin->messages, walk);
988 gst_message_unref (message);
990 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
991 "not deleting message %p of type 0x%08x", message,
992 GST_MESSAGE_TYPE (message));
998 /* Check if the bin is EOS. We do this by scanning all sinks and
999 * checking if they posted an EOS message.
1001 * call with bin LOCK */
1003 is_eos (GstBin * bin, guint32 * seqnum)
1010 for (walk = bin->children; walk; walk = g_list_next (walk)) {
1011 GstElement *element;
1013 element = GST_ELEMENT_CAST (walk->data);
1014 if (bin_element_is_sink (element, bin) == 0) {
1015 /* check if element posted EOS */
1017 find_message (bin, GST_OBJECT_CAST (element), GST_MESSAGE_EOS))) {
1018 GST_DEBUG ("sink '%s' posted EOS", GST_ELEMENT_NAME (element));
1019 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1022 GST_DEBUG ("sink '%s' did not post EOS yet",
1023 GST_ELEMENT_NAME (element));
1029 /* FIXME: Some tests (e.g. elements/capsfilter) use
1030 * pipelines with a dangling sinkpad but no sink element.
1031 * These tests assume that no EOS message is ever
1032 * posted on the bus so let's keep that behaviour.
1033 * In valid pipelines this doesn't make a difference.
1035 return result && n_eos > 0;
1039 /* Check if the bin is STREAM_START. We do this by scanning all sinks and
1040 * checking if they posted an STREAM_START message.
1042 * call with bin LOCK */
1044 is_stream_start (GstBin * bin, guint32 * seqnum, gboolean * have_group_id,
1050 gboolean first = TRUE, same_group_id = TRUE;
1052 *have_group_id = TRUE;
1055 for (walk = bin->children; walk; walk = g_list_next (walk)) {
1056 GstElement *element;
1058 element = GST_ELEMENT_CAST (walk->data);
1059 if (bin_element_is_sink (element, bin) == 0) {
1060 /* check if element posted STREAM_START */
1062 find_message (bin, GST_OBJECT_CAST (element),
1063 GST_MESSAGE_STREAM_START))) {
1064 GST_DEBUG ("sink '%s' posted STREAM_START", GST_ELEMENT_NAME (element));
1065 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1066 if (gst_message_parse_group_id (GST_MESSAGE_CAST (msgs->data),
1070 *group_id = tmp_group_id;
1072 if (tmp_group_id != *group_id)
1073 same_group_id = FALSE;
1076 *have_group_id = FALSE;
1079 GST_DEBUG ("sink '%s' did not post STREAM_START yet",
1080 GST_ELEMENT_NAME (element));
1087 /* If all have a group_id we only consider this stream started
1088 * if all group ids were the same and all sinks posted a stream-start
1091 return same_group_id && result;
1092 /* otherwise consider this stream started after all sinks
1093 * have reported stream-start for backward compatibility.
1094 * FIXME 2.0: This should go away! */
1099 unlink_pads (const GValue * item, gpointer user_data)
1104 pad = g_value_get_object (item);
1106 if ((peer = gst_pad_get_peer (pad))) {
1107 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
1108 gst_pad_unlink (pad, peer);
1110 gst_pad_unlink (peer, pad);
1111 gst_object_unref (peer);
1116 bin_deep_iterator_foreach (const GValue * item, gpointer user_data)
1118 GQueue *queue = user_data;
1120 g_queue_push_tail (queue, g_value_dup_object (item));
1124 gst_bin_do_deep_add_remove (GstBin * bin, gint sig_id, const gchar * sig_name,
1125 GstElement * element)
1127 g_signal_emit (bin, sig_id, 0, bin, element);
1129 /* When removing a bin, emit deep-element-* for everything in the bin too */
1130 if (GST_IS_BIN (element)) {
1132 GstIteratorResult ires;
1133 GQueue elements = G_QUEUE_INIT;
1135 GST_LOG_OBJECT (bin, "Recursing into bin %" GST_PTR_FORMAT " for %s",
1137 it = gst_bin_iterate_recurse (GST_BIN_CAST (element));
1139 ires = gst_iterator_foreach (it, bin_deep_iterator_foreach, &elements);
1140 if (ires != GST_ITERATOR_DONE) {
1141 g_queue_foreach (&elements, (GFunc) g_object_unref, NULL);
1142 g_queue_clear (&elements);
1144 } while (ires == GST_ITERATOR_RESYNC);
1145 if (ires != GST_ITERATOR_ERROR) {
1148 while ((e = g_queue_pop_head (&elements))) {
1149 GstObject *parent = gst_object_get_parent (GST_OBJECT_CAST (e));
1151 GST_LOG_OBJECT (bin, "calling %s for element %" GST_PTR_FORMAT
1152 " in bin %" GST_PTR_FORMAT, sig_name, e, parent);
1153 g_signal_emit (bin, sig_id, 0, parent, e);
1154 gst_object_unref (parent);
1158 gst_iterator_free (it);
1162 /* vmethod that adds an element to a bin
1167 gst_bin_add_func (GstBin * bin, GstElement * element)
1171 gboolean is_sink, is_source, provides_clock, requires_clock;
1172 GstMessage *clock_message = NULL, *async_message = NULL;
1173 GstStateChangeReturn ret;
1174 GList *l, *elem_contexts, *need_context_messages;
1176 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1178 /* we obviously can't add ourself to ourself */
1179 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1182 /* get the element name to make sure it is unique in this bin. */
1183 GST_OBJECT_LOCK (element);
1184 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1185 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1186 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1188 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1190 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1191 GST_OBJECT_UNLOCK (element);
1193 GST_OBJECT_LOCK (bin);
1195 /* then check to see if the element's name is already taken in the bin,
1196 * we can safely take the lock here. This check is probably bogus because
1197 * you can safely change the element name after this check and before setting
1198 * the object parent. The window is very small though... */
1199 if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
1200 goto duplicate_name;
1202 /* set the element's parent and add the element to the bin's list of children */
1203 if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
1204 GST_OBJECT_CAST (bin))))
1207 /* if we add a sink we become a sink */
1209 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
1211 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SINK);
1214 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was source",
1216 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SOURCE);
1218 if (provides_clock) {
1219 GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
1221 gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
1222 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1224 if (requires_clock) {
1225 GST_DEBUG_OBJECT (bin, "element \"%s\" requires a clock", elem_name);
1226 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1229 bin->children = g_list_prepend (bin->children, element);
1231 bin->children_cookie++;
1232 if (!GST_BIN_IS_NO_RESYNC (bin))
1233 bin->priv->structure_cookie++;
1235 /* distribute the bus */
1236 gst_element_set_bus (element, bin->child_bus);
1238 /* propagate the current base_time, start_time and clock */
1239 gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
1240 gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
1241 /* it's possible that the element did not accept the clock but
1242 * that is not important right now. When the pipeline goes to PLAYING,
1243 * a new clock will be selected */
1244 gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
1246 /* get the element's list of contexts before propagating our own */
1247 elem_contexts = gst_element_get_contexts (element);
1248 for (l = GST_ELEMENT_CAST (bin)->contexts; l; l = l->next)
1249 gst_element_set_context (element, l->data);
1251 need_context_messages = NULL;
1252 for (l = elem_contexts; l; l = l->next) {
1253 GstContext *replacement, *context = l->data;
1254 const gchar *context_type;
1256 context_type = gst_context_get_context_type (context);
1258 /* we already set this context above? */
1260 gst_element_get_context_unlocked (GST_ELEMENT (bin), context_type);
1262 gst_context_unref (replacement);
1267 /* ask our parent for the context */
1268 msg = gst_message_new_need_context (GST_OBJECT_CAST (bin), context_type);
1269 s = (GstStructure *) gst_message_get_structure (msg);
1270 gst_structure_set (s, "bin.old.context", GST_TYPE_CONTEXT, context, NULL);
1272 need_context_messages = g_list_prepend (need_context_messages, msg);
1277 /* set the cached index on the children */
1278 if (bin->priv->index)
1279 gst_element_set_index (element, bin->priv->index);
1282 ret = GST_STATE_RETURN (bin);
1283 /* no need to update the state if we are in error */
1284 if (ret == GST_STATE_CHANGE_FAILURE)
1285 goto no_state_recalc;
1287 /* update the bin state, the new element could have been an ASYNC or
1288 * NO_PREROLL element */
1289 ret = GST_STATE_RETURN (element);
1290 GST_DEBUG_OBJECT (bin, "added %s element",
1291 gst_element_state_change_return_get_name (ret));
1294 case GST_STATE_CHANGE_ASYNC:
1296 /* create message to track this aync element when it posts an async-done
1298 async_message = gst_message_new_async_start (GST_OBJECT_CAST (element));
1301 case GST_STATE_CHANGE_NO_PREROLL:
1302 /* ignore all async elements we might have and commit our state */
1303 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1305 case GST_STATE_CHANGE_FAILURE:
1312 GST_OBJECT_UNLOCK (bin);
1314 for (l = need_context_messages; l; l = l->next) {
1315 GstMessage *msg = l->data;
1317 const gchar *context_type;
1318 GstContext *replacement, *context;
1320 gst_message_parse_context_type (msg, &context_type);
1322 GST_LOG_OBJECT (bin, "asking parent for context type: %s "
1323 "from %" GST_PTR_FORMAT, context_type, element);
1325 s = (GstStructure *) gst_message_get_structure (msg);
1326 gst_structure_get (s, "bin.old.context", GST_TYPE_CONTEXT, &context, NULL);
1327 gst_structure_remove_field (s, "bin.old.context");
1328 gst_element_post_message (GST_ELEMENT_CAST (bin), msg);
1330 /* lock to avoid losing a potential write */
1331 GST_OBJECT_LOCK (bin);
1333 gst_element_get_context_unlocked (GST_ELEMENT_CAST (bin), context_type);
1336 /* we got the context set from GstElement::set_context */
1337 gst_context_unref (replacement);
1338 GST_OBJECT_UNLOCK (bin);
1340 /* Propagate the element's context upwards */
1341 GST_LOG_OBJECT (bin, "propagating existing context type: %s %p "
1342 "from %" GST_PTR_FORMAT, context_type, context, element);
1344 gst_bin_update_context_unlocked (bin, context);
1347 gst_message_new_have_context (GST_OBJECT_CAST (bin),
1348 gst_context_ref (context));
1349 GST_OBJECT_UNLOCK (bin);
1350 gst_element_post_message (GST_ELEMENT_CAST (bin), msg);
1352 gst_context_unref (context);
1354 g_list_free_full (elem_contexts, (GDestroyNotify) gst_context_unref);
1355 g_list_free (need_context_messages);
1357 /* post the messages on the bus of the element so that the bin can handle
1360 gst_element_post_message (element, clock_message);
1363 gst_element_post_message (element, async_message);
1365 /* unlink all linked pads */
1366 it = gst_element_iterate_pads (element);
1367 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1368 gst_iterator_free (it);
1370 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
1373 g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
1374 gst_child_proxy_child_added ((GstChildProxy *) bin, (GObject *) element,
1377 gst_bin_do_deep_add_remove (bin, gst_bin_signals[DEEP_ELEMENT_ADDED],
1378 "deep-element-added", element);
1384 /* ERROR handling here */
1387 GST_OBJECT_LOCK (bin);
1388 g_warning ("Cannot add bin '%s' to itself", GST_ELEMENT_NAME (bin));
1389 GST_OBJECT_UNLOCK (bin);
1394 g_warning ("Name '%s' is not unique in bin '%s', not adding",
1395 elem_name, GST_ELEMENT_NAME (bin));
1396 GST_OBJECT_UNLOCK (bin);
1402 g_warning ("Element '%s' already has parent", elem_name);
1403 GST_OBJECT_UNLOCK (bin);
1409 /* signal vfunc, will be called when a new element was added */
1411 gst_bin_deep_element_added_func (GstBin * bin, GstBin * sub_bin,
1416 parent_bin = (GstBin *) gst_object_get_parent (GST_OBJECT_CAST (bin));
1417 if (parent_bin == NULL) {
1418 GST_LOG_OBJECT (bin, "no parent, reached top-level");
1422 GST_LOG_OBJECT (parent_bin, "emitting deep-element-added for element "
1423 "%" GST_PTR_FORMAT " which has just been added to %" GST_PTR_FORMAT,
1426 g_signal_emit (parent_bin, gst_bin_signals[DEEP_ELEMENT_ADDED], 0, sub_bin,
1429 gst_object_unref (parent_bin);
1432 /* signal vfunc, will be called when an element was removed */
1434 gst_bin_deep_element_removed_func (GstBin * bin, GstBin * sub_bin,
1439 parent_bin = (GstBin *) gst_object_get_parent (GST_OBJECT_CAST (bin));
1440 if (parent_bin == NULL) {
1441 GST_LOG_OBJECT (bin, "no parent, reached top-level");
1445 GST_LOG_OBJECT (parent_bin, "emitting deep-element-removed for element "
1446 "%" GST_PTR_FORMAT " which has just been removed from %" GST_PTR_FORMAT,
1449 g_signal_emit (parent_bin, gst_bin_signals[DEEP_ELEMENT_REMOVED], 0, sub_bin,
1452 gst_object_unref (parent_bin);
1458 * @element: (transfer full): the #GstElement to add
1460 * Adds the given element to the bin. Sets the element's parent, and thus
1461 * takes ownership of the element. An element can only be added to one bin.
1463 * If the element's pads are linked to other pads, the pads will be unlinked
1464 * before the element is added to the bin.
1467 * When you add an element to an already-running pipeline, you will have to
1468 * take care to set the state of the newly-added element to the desired
1469 * state (usually PLAYING or PAUSED, same you set the pipeline to originally)
1470 * with gst_element_set_state(), or use gst_element_sync_state_with_parent().
1471 * The bin or pipeline will not take care of this for you.
1476 * Returns: %TRUE if the element could be added, %FALSE if
1477 * the bin does not want to accept the element.
1480 gst_bin_add (GstBin * bin, GstElement * element)
1482 GstBinClass *bclass;
1485 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1486 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1487 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1489 bclass = GST_BIN_GET_CLASS (bin);
1491 if (G_UNLIKELY (bclass->add_element == NULL))
1494 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1495 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1496 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1498 GST_TRACER_BIN_ADD_PRE (bin, element);
1499 result = bclass->add_element (bin, element);
1500 GST_TRACER_BIN_ADD_POST (bin, element, result);
1504 /* ERROR handling */
1507 g_warning ("adding elements to bin '%s' is not supported",
1508 GST_ELEMENT_NAME (bin));
1513 /* remove an element from the bin
1518 gst_bin_remove_func (GstBin * bin, GstElement * element)
1522 gboolean is_sink, is_source, provides_clock, requires_clock;
1523 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1524 GstMessage *clock_message = NULL;
1525 GstClock **provided_clock_p;
1526 GstElement **clock_provider_p;
1528 gboolean other_async, this_async, have_no_preroll;
1529 GstStateChangeReturn ret;
1531 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1533 /* we obviously can't remove ourself from ourself */
1534 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1535 goto removing_itself;
1537 GST_OBJECT_LOCK (bin);
1539 GST_OBJECT_LOCK (element);
1540 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1542 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1545 /* remove the parent ref */
1546 GST_OBJECT_PARENT (element) = NULL;
1548 /* grab element name so we can print it */
1549 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1550 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1552 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1554 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1555 GST_OBJECT_UNLOCK (element);
1559 othersource = FALSE;
1560 otherprovider = FALSE;
1561 otherrequirer = FALSE;
1562 have_no_preroll = FALSE;
1563 /* iterate the elements, we collect which ones are async and no_preroll. We
1564 * also remove the element when we find it. */
1565 for (walk = bin->children; walk; walk = next) {
1566 GstElement *child = GST_ELEMENT_CAST (walk->data);
1568 next = g_list_next (walk);
1570 if (child == element) {
1572 /* remove the element */
1573 bin->children = g_list_delete_link (bin->children, walk);
1575 gboolean child_sink, child_source, child_provider, child_requirer;
1577 GST_OBJECT_LOCK (child);
1578 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1579 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1581 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1583 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1584 /* when we remove a sink, check if there are other sinks. */
1585 if (is_sink && !othersink && child_sink)
1587 if (is_source && !othersource && child_source)
1589 if (provides_clock && !otherprovider && child_provider)
1590 otherprovider = TRUE;
1591 if (requires_clock && !otherrequirer && child_requirer)
1592 otherrequirer = TRUE;
1593 /* check if we have NO_PREROLL children */
1594 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1595 have_no_preroll = TRUE;
1596 GST_OBJECT_UNLOCK (child);
1600 /* the element must have been in the bin's list of children */
1601 if (G_UNLIKELY (!found))
1604 /* we now removed the element from the list of elements, increment the cookie
1605 * so that others can detect a change in the children list. */
1607 bin->children_cookie++;
1608 if (!GST_BIN_IS_NO_RESYNC (bin))
1609 bin->priv->structure_cookie++;
1611 if (is_sink && !othersink) {
1612 /* we're not a sink anymore */
1613 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1614 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1616 if (is_source && !othersource) {
1617 /* we're not a source anymore */
1618 GST_DEBUG_OBJECT (bin, "we removed the last source");
1619 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1621 if (provides_clock && !otherprovider) {
1622 /* we're not a clock provider anymore */
1623 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1624 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1626 if (requires_clock && !otherrequirer) {
1627 /* we're not a clock requirer anymore */
1628 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1629 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1632 /* if the clock provider for this element is removed, we lost
1633 * the clock as well, we need to inform the parent of this
1634 * so that it can select a new clock */
1635 if (bin->clock_provider == element) {
1636 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1637 bin->clock_dirty = TRUE;
1639 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1640 provided_clock_p = &bin->provided_clock;
1641 clock_provider_p = &bin->clock_provider;
1642 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1643 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1646 /* remove messages for the element, if there was a pending ASYNC_START
1647 * message we must see if removing the element caused the bin to lose its
1650 other_async = FALSE;
1651 for (walk = bin->messages; walk; walk = next) {
1652 GstMessage *message = (GstMessage *) walk->data;
1653 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1656 next = g_list_next (walk);
1659 switch (GST_MESSAGE_TYPE (message)) {
1660 case GST_MESSAGE_ASYNC_START:
1666 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1668 case GST_MESSAGE_STRUCTURE_CHANGE:
1672 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1674 /* it's unlikely that this message is still in the list of messages
1675 * because this would mean that a link/unlink is busy in another thread
1676 * while we remove the element. We still have to remove the message
1677 * because we might not receive the done message anymore when the element
1678 * is removed from the bin. */
1679 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1680 if (owner == element)
1691 /* delete all message types */
1692 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1693 message, elem_name);
1694 bin->messages = g_list_delete_link (bin->messages, walk);
1695 gst_message_unref (message);
1699 /* get last return */
1700 ret = GST_STATE_RETURN (bin);
1702 /* no need to update the state if we are in error */
1703 if (ret == GST_STATE_CHANGE_FAILURE)
1704 goto no_state_recalc;
1706 if (!other_async && this_async) {
1707 /* all other elements were not async and we removed the async one,
1708 * handle the async-done case because we are not async anymore now. */
1709 GST_DEBUG_OBJECT (bin,
1710 "we removed the last async element, have no_preroll %d",
1713 /* the current state return of the bin depends on if there are no_preroll
1714 * elements in the pipeline or not */
1715 if (have_no_preroll)
1716 ret = GST_STATE_CHANGE_NO_PREROLL;
1718 ret = GST_STATE_CHANGE_SUCCESS;
1720 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1722 GST_DEBUG_OBJECT (bin,
1723 "recalc state preroll: %d, other async: %d, this async %d",
1724 have_no_preroll, other_async, this_async);
1726 if (have_no_preroll) {
1727 ret = GST_STATE_CHANGE_NO_PREROLL;
1728 } else if (other_async) {
1729 /* there are other async elements and we were not doing an async state
1730 * change, change our pending state and go async */
1731 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1732 GST_STATE_NEXT (bin) = GST_STATE (bin);
1733 GST_STATE_PENDING (bin) = GST_STATE (bin);
1735 ret = GST_STATE_CHANGE_ASYNC;
1737 GST_STATE_RETURN (bin) = ret;
1741 gst_element_set_bus (element, NULL);
1742 /* Clear the clock we provided to the element */
1743 gst_element_set_clock (element, NULL);
1744 GST_OBJECT_UNLOCK (bin);
1747 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1749 /* unlink all linked pads */
1750 it = gst_element_iterate_pads (element);
1751 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1752 gst_iterator_free (it);
1754 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1757 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1758 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1761 gst_bin_do_deep_add_remove (bin, gst_bin_signals[DEEP_ELEMENT_REMOVED],
1762 "deep-element-removed", element);
1765 /* element is really out of our control now */
1766 gst_object_unref (element);
1770 /* ERROR handling */
1773 GST_OBJECT_LOCK (bin);
1774 g_warning ("Cannot remove bin '%s' from itself", GST_ELEMENT_NAME (bin));
1775 GST_OBJECT_UNLOCK (bin);
1780 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1781 GST_ELEMENT_NAME (bin));
1782 GST_OBJECT_UNLOCK (element);
1783 GST_OBJECT_UNLOCK (bin);
1792 * @element: (transfer none): the #GstElement to remove
1794 * Removes the element from the bin, unparenting it as well.
1795 * Unparenting the element means that the element will be dereferenced,
1796 * so if the bin holds the only reference to the element, the element
1797 * will be freed in the process of removing it from the bin. If you
1798 * want the element to still exist after removing, you need to call
1799 * gst_object_ref() before removing it from the bin.
1801 * If the element's pads are linked to other pads, the pads will be unlinked
1802 * before the element is removed from the bin.
1806 * Returns: %TRUE if the element could be removed, %FALSE if
1807 * the bin does not want to remove the element.
1810 gst_bin_remove (GstBin * bin, GstElement * element)
1812 GstBinClass *bclass;
1815 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1816 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1817 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1819 bclass = GST_BIN_GET_CLASS (bin);
1821 if (G_UNLIKELY (bclass->remove_element == NULL))
1824 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1825 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1827 GST_TRACER_BIN_REMOVE_PRE (bin, element);
1828 result = bclass->remove_element (bin, element);
1829 GST_TRACER_BIN_REMOVE_POST (bin, result);
1833 /* ERROR handling */
1836 g_warning ("removing elements from bin '%s' is not supported",
1837 GST_ELEMENT_NAME (bin));
1843 * gst_bin_iterate_elements:
1846 * Gets an iterator for the elements in this bin.
1848 * MT safe. Caller owns returned value.
1850 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1854 gst_bin_iterate_elements (GstBin * bin)
1856 GstIterator *result;
1858 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1860 GST_OBJECT_LOCK (bin);
1861 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1862 GST_OBJECT_GET_LOCK (bin),
1863 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1864 GST_OBJECT_UNLOCK (bin);
1869 static GstIteratorItem
1870 iterate_child_recurse (GstIterator * it, const GValue * item)
1872 GstElement *child = g_value_get_object (item);
1874 if (GST_IS_BIN (child)) {
1875 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1877 gst_iterator_push (it, other);
1879 return GST_ITERATOR_ITEM_PASS;
1883 * gst_bin_iterate_recurse:
1886 * Gets an iterator for the elements in this bin.
1887 * This iterator recurses into GstBin children.
1889 * MT safe. Caller owns returned value.
1891 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1895 gst_bin_iterate_recurse (GstBin * bin)
1897 GstIterator *result;
1899 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1901 GST_OBJECT_LOCK (bin);
1902 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1903 GST_OBJECT_GET_LOCK (bin),
1904 &bin->children_cookie,
1906 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1907 GST_OBJECT_UNLOCK (bin);
1912 /* returns 0 when TRUE because this is a GCompareFunc */
1915 bin_element_is_sink (GstElement * child, GstBin * bin)
1919 /* we lock the child here for the remainder of the function to
1920 * get its name and flag safely. */
1921 GST_OBJECT_LOCK (child);
1922 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1924 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1925 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1927 GST_OBJECT_UNLOCK (child);
1928 return is_sink ? 0 : 1;
1932 sink_iterator_filter (const GValue * vchild, GValue * vbin)
1934 GstBin *bin = g_value_get_object (vbin);
1935 GstElement *child = g_value_get_object (vchild);
1937 return (bin_element_is_sink (child, bin));
1941 * gst_bin_iterate_sinks:
1944 * Gets an iterator for all elements in the bin that have the
1945 * #GST_ELEMENT_FLAG_SINK flag set.
1947 * MT safe. Caller owns returned value.
1949 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1953 gst_bin_iterate_sinks (GstBin * bin)
1955 GstIterator *children;
1956 GstIterator *result;
1957 GValue vbin = { 0, };
1959 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1961 g_value_init (&vbin, GST_TYPE_BIN);
1962 g_value_set_object (&vbin, bin);
1964 children = gst_bin_iterate_elements (bin);
1965 result = gst_iterator_filter (children,
1966 (GCompareFunc) sink_iterator_filter, &vbin);
1968 g_value_unset (&vbin);
1973 /* returns 0 when TRUE because this is a GCompareFunc */
1976 bin_element_is_src (GstElement * child, GstBin * bin)
1980 /* we lock the child here for the remainder of the function to
1981 * get its name and other info safely. */
1982 GST_OBJECT_LOCK (child);
1983 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1985 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1986 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
1988 GST_OBJECT_UNLOCK (child);
1989 return is_src ? 0 : 1;
1993 src_iterator_filter (const GValue * vchild, GValue * vbin)
1995 GstBin *bin = g_value_get_object (vbin);
1996 GstElement *child = g_value_get_object (vchild);
1998 return (bin_element_is_src (child, bin));
2002 * gst_bin_iterate_sources:
2005 * Gets an iterator for all elements in the bin that have the
2006 * #GST_ELEMENT_FLAG_SOURCE flag set.
2008 * MT safe. Caller owns returned value.
2010 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
2014 gst_bin_iterate_sources (GstBin * bin)
2016 GstIterator *children;
2017 GstIterator *result;
2018 GValue vbin = { 0, };
2020 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2022 g_value_init (&vbin, GST_TYPE_BIN);
2023 g_value_set_object (&vbin, bin);
2025 children = gst_bin_iterate_elements (bin);
2026 result = gst_iterator_filter (children,
2027 (GCompareFunc) src_iterator_filter, &vbin);
2029 g_value_unset (&vbin);
2037 static GstStateChangeReturn
2038 gst_bin_get_state_func (GstElement * element, GstState * state,
2039 GstState * pending, GstClockTime timeout)
2041 GstStateChangeReturn ret;
2043 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
2046 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
2052 /***********************************************
2053 * Topologically sorted iterator
2054 * see http://en.wikipedia.org/wiki/Topological_sorting
2056 * For each element in the graph, an entry is kept in a HashTable
2057 * with its number of srcpad connections (degree).
2058 * We then change state of all elements without dependencies
2059 * (degree 0) and decrement the degree of all elements connected
2060 * on the sinkpads. When an element reaches degree 0, its state is
2062 * When all elements are handled the algorithm stops.
2064 typedef struct _GstBinSortIterator
2067 GQueue queue; /* elements queued for state change */
2068 GstBin *bin; /* bin we iterate */
2069 gint mode; /* adding or removing dependency */
2070 GstElement *best; /* next element with least dependencies */
2071 gint best_deg; /* best degree */
2072 GHashTable *hash; /* hashtable with element dependencies */
2073 gboolean dirty; /* we detected structure change */
2074 } GstBinSortIterator;
2077 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
2078 GstBinSortIterator * copy)
2080 GHashTableIter iter;
2081 gpointer key, value;
2083 copy->queue = it->queue;
2084 g_queue_foreach (©->queue, (GFunc) gst_object_ref, NULL);
2086 copy->bin = gst_object_ref (it->bin);
2088 copy->best = gst_object_ref (it->best);
2090 copy->hash = g_hash_table_new (NULL, NULL);
2091 g_hash_table_iter_init (&iter, it->hash);
2092 while (g_hash_table_iter_next (&iter, &key, &value))
2093 g_hash_table_insert (copy->hash, key, value);
2096 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
2097 #define HASH_SET_DEGREE(bit, elem, deg) \
2098 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
2099 #define HASH_GET_DEGREE(bit, elem) \
2100 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
2102 /* add element to queue of next elements in the iterator.
2103 * We push at the tail to give higher priority elements a
2106 add_to_queue (GstBinSortIterator * bit, GstElement * element)
2108 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
2109 GST_ELEMENT_NAME (element));
2110 gst_object_ref (element);
2111 g_queue_push_tail (&bit->queue, element);
2112 HASH_SET_DEGREE (bit, element, -1);
2116 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
2120 if ((find = g_queue_find (&bit->queue, element))) {
2121 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
2122 GST_ELEMENT_NAME (element));
2124 g_queue_delete_link (&bit->queue, find);
2125 gst_object_unref (element);
2127 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
2128 GST_ELEMENT_NAME (element));
2132 /* clear the queue, unref all objects as we took a ref when
2133 * we added them to the queue */
2135 clear_queue (GQueue * queue)
2139 while ((p = g_queue_pop_head (queue)))
2140 gst_object_unref (p);
2143 /* set all degrees to 0. Elements marked as a sink are
2144 * added to the queue immediately. Since we only look at the SINK flag of the
2145 * element, it is possible that we add non-sinks to the queue. These will be
2146 * removed from the queue again when we can prove that it provides data for some
2149 reset_degree (GstElement * element, GstBinSortIterator * bit)
2153 /* sinks are added right away */
2154 GST_OBJECT_LOCK (element);
2155 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
2156 GST_OBJECT_UNLOCK (element);
2159 add_to_queue (bit, element);
2161 /* others are marked with 0 and handled when sinks are done */
2162 HASH_SET_DEGREE (bit, element, 0);
2166 /* adjust the degree of all elements connected to the given
2167 * element. If a degree of an element drops to 0, it is
2168 * added to the queue of elements to schedule next.
2170 * We have to make sure not to cross the bin boundary this element
2174 update_degree (GstElement * element, GstBinSortIterator * bit)
2176 gboolean linked = FALSE;
2178 GST_OBJECT_LOCK (element);
2179 /* don't touch degree if element has no sinkpads */
2180 if (element->numsinkpads != 0) {
2181 /* loop over all sinkpads, decrement degree for all connected
2182 * elements in this bin */
2185 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
2188 pad = GST_PAD_CAST (pads->data);
2190 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
2191 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
2192 GST_MESSAGE_STRUCTURE_CHANGE))) {
2193 /* mark the iterator as dirty because we won't be updating the degree
2194 * of the peer parent now. This would result in the 'loop detected'
2195 * later on because the peer parent element could become the best next
2196 * element with a degree > 0. We will simply continue our state
2197 * changes and we'll eventually resync when the unlink completed and
2198 * the iterator cookie is updated. */
2203 if ((peer = gst_pad_get_peer (pad))) {
2204 GstElement *peer_element;
2206 if ((peer_element = gst_pad_get_parent_element (peer))) {
2207 GST_OBJECT_LOCK (peer_element);
2208 /* check that we don't go outside of this bin */
2209 if (GST_OBJECT_CAST (peer_element)->parent ==
2210 GST_OBJECT_CAST (bit->bin)) {
2211 gint old_deg, new_deg;
2213 old_deg = HASH_GET_DEGREE (bit, peer_element);
2215 /* check to see if we added an element as sink that was not really a
2216 * sink because it was connected to some other element. */
2217 if (old_deg == -1) {
2218 remove_from_queue (bit, peer_element);
2221 new_deg = old_deg + bit->mode;
2223 GST_DEBUG_OBJECT (bit->bin,
2224 "change element %s, degree %d->%d, linked to %s",
2225 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
2226 GST_ELEMENT_NAME (element));
2228 /* update degree, it is possible that an element was in 0 and
2229 * reaches -1 here. This would mean that the element had no sinkpads
2230 * but became linked while the state change was happening. We will
2231 * resync on this with the structure change message. */
2233 /* degree hit 0, add to queue */
2234 add_to_queue (bit, peer_element);
2236 HASH_SET_DEGREE (bit, peer_element, new_deg);
2240 GST_OBJECT_UNLOCK (peer_element);
2241 gst_object_unref (peer_element);
2243 gst_object_unref (peer);
2248 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2249 GST_ELEMENT_NAME (element));
2251 GST_OBJECT_UNLOCK (element);
2254 /* find the next best element not handled yet. This is the one
2255 * with the lowest non-negative degree */
2257 find_element (GstElement * element, GstBinSortIterator * bit)
2261 /* element is already handled */
2262 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2265 /* first element or element with smaller degree */
2266 if (bit->best == NULL || bit->best_deg > degree) {
2267 bit->best = element;
2268 bit->best_deg = degree;
2272 /* get next element in iterator. */
2273 static GstIteratorResult
2274 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2277 GstBin *bin = bit->bin;
2279 /* empty queue, we have to find a next best element */
2280 if (g_queue_is_empty (&bit->queue)) {
2282 bit->best_deg = G_MAXINT;
2283 g_list_foreach (bin->children, (GFunc) find_element, bit);
2284 if ((best = bit->best)) {
2285 /* when we detected an unlink, don't warn because our degrees might be
2286 * screwed up. We will resync later */
2287 if (bit->best_deg != 0 && !bit->dirty) {
2288 /* we don't fail on this one yet */
2289 GST_WARNING_OBJECT (bin, "loop dected in graph");
2290 g_warning ("loop detected in the graph of bin '%s'!!",
2291 GST_ELEMENT_NAME (bin));
2293 /* best unhandled element, schedule as next element */
2294 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2295 GST_ELEMENT_NAME (best));
2296 HASH_SET_DEGREE (bit, best, -1);
2297 g_value_set_object (result, best);
2299 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2300 /* no more unhandled elements, we are done */
2301 return GST_ITERATOR_DONE;
2304 /* everything added to the queue got reffed */
2305 best = g_queue_pop_head (&bit->queue);
2306 g_value_set_object (result, best);
2307 gst_object_unref (best);
2310 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2311 /* update degrees of linked elements */
2312 update_degree (best, bit);
2314 return GST_ITERATOR_OK;
2317 /* clear queues, recalculate the degrees and restart. */
2319 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2321 GstBin *bin = bit->bin;
2323 GST_DEBUG_OBJECT (bin, "resync");
2325 clear_queue (&bit->queue);
2327 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2328 /* calc degrees, incrementing */
2330 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2331 /* for the rest of the function we decrement the degrees */
2335 /* clear queues, unref bin and free iterator. */
2337 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2339 GstBin *bin = bit->bin;
2341 GST_DEBUG_OBJECT (bin, "free");
2342 clear_queue (&bit->queue);
2343 g_hash_table_destroy (bit->hash);
2344 gst_object_unref (bin);
2347 /* should be called with the bin LOCK held */
2348 static GstIterator *
2349 gst_bin_sort_iterator_new (GstBin * bin)
2351 GstBinSortIterator *result;
2353 /* we don't need an ItemFunction because we ref the items in the _next
2355 result = (GstBinSortIterator *)
2356 gst_iterator_new (sizeof (GstBinSortIterator),
2358 GST_OBJECT_GET_LOCK (bin),
2359 &bin->priv->structure_cookie,
2360 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2361 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2362 (GstIteratorItemFunction) NULL,
2363 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2364 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2365 g_queue_init (&result->queue);
2366 result->hash = g_hash_table_new (NULL, NULL);
2367 gst_object_ref (bin);
2369 gst_bin_sort_iterator_resync (result);
2371 return (GstIterator *) result;
2375 * gst_bin_iterate_sorted:
2378 * Gets an iterator for the elements in this bin in topologically
2379 * sorted order. This means that the elements are returned from
2380 * the most downstream elements (sinks) to the sources.
2382 * This function is used internally to perform the state changes
2383 * of the bin elements and for clock selection.
2385 * MT safe. Caller owns returned value.
2387 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
2391 gst_bin_iterate_sorted (GstBin * bin)
2393 GstIterator *result;
2395 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2397 GST_OBJECT_LOCK (bin);
2398 result = gst_bin_sort_iterator_new (bin);
2399 GST_OBJECT_UNLOCK (bin);
2404 static GstStateChangeReturn
2405 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2406 GstClockTime base_time, GstClockTime start_time, GstState current,
2409 GstStateChangeReturn ret;
2410 GstState child_current, child_pending;
2414 GST_STATE_LOCK (element);
2416 GST_OBJECT_LOCK (element);
2417 /* set base_time and start time on child */
2418 GST_ELEMENT_START_TIME (element) = start_time;
2419 element->base_time = base_time;
2420 /* peel off the locked flag */
2421 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2422 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2423 ret = GST_STATE_RETURN (element);
2424 child_current = GST_STATE (element);
2425 child_pending = GST_STATE_PENDING (element);
2426 GST_OBJECT_UNLOCK (element);
2428 /* skip locked elements */
2429 if (G_UNLIKELY (locked))
2432 /* if the element was no preroll, just start changing the state regardless
2433 * if it had async elements (in the case of a bin) because they won't preroll
2435 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2436 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2440 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2441 "current %s pending %s, desired next %s",
2442 gst_element_state_get_name (child_current),
2443 gst_element_state_get_name (child_pending),
2444 gst_element_state_get_name (next));
2446 /* always recurse into bins so that we can set the base time */
2447 if (GST_IS_BIN (element))
2450 /* Try not to change the state of elements that are already in the state we're
2452 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2453 /* child is already at the requested state, return previous return. Note that
2454 * if the child has a pending state to next, we will still call the
2455 * set_state function */
2457 } else if (next > current) {
2458 /* upward state change */
2459 if (child_pending == GST_STATE_VOID_PENDING) {
2460 /* .. and the child is not busy doing anything */
2461 if (child_current > next) {
2462 /* .. and is already past the requested state, assume it got there
2464 ret = GST_STATE_CHANGE_SUCCESS;
2467 } else if (child_pending > child_current) {
2468 /* .. and the child is busy going upwards */
2469 if (child_current >= next) {
2470 /* .. and is already past the requested state, assume it got there
2472 ret = GST_STATE_CHANGE_SUCCESS;
2476 /* .. and the child is busy going downwards */
2477 if (child_current > next) {
2478 /* .. and is already past the requested state, assume it got there
2480 ret = GST_STATE_CHANGE_SUCCESS;
2484 } else if (next < current) {
2485 /* downward state change */
2486 if (child_pending == GST_STATE_VOID_PENDING) {
2487 /* .. and the child is not busy doing anything */
2488 if (child_current < next) {
2489 /* .. and is already past the requested state, assume it got there
2491 ret = GST_STATE_CHANGE_SUCCESS;
2494 } else if (child_pending < child_current) {
2495 /* .. and the child is busy going downwards */
2496 if (child_current <= next) {
2497 /* .. and is already past the requested state, assume it got there
2499 ret = GST_STATE_CHANGE_SUCCESS;
2503 /* .. and the child is busy going upwards */
2504 if (child_current < next) {
2505 /* .. and is already past the requested state, assume it got there
2507 ret = GST_STATE_CHANGE_SUCCESS;
2514 GST_OBJECT_LOCK (bin);
2515 /* the element was busy with an upwards async state change, we must wait for
2516 * an ASYNC_DONE message before we attemp to change the state. */
2518 find_message (bin, GST_OBJECT_CAST (element),
2519 GST_MESSAGE_ASYNC_START))) {
2520 #ifndef GST_DISABLE_GST_DEBUG
2521 GstMessage *message = GST_MESSAGE_CAST (found->data);
2523 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2524 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2526 /* only wait for upward state changes */
2527 if (next > current) {
2528 /* We found an async element check if we can force its state to change or
2529 * if we have to wait for it to preroll. */
2533 GST_OBJECT_UNLOCK (bin);
2536 GST_DEBUG_OBJECT (bin,
2537 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2538 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2539 GST_TIME_ARGS (base_time));
2542 ret = gst_element_set_state (element, next);
2544 GST_STATE_UNLOCK (element);
2550 GST_DEBUG_OBJECT (element,
2551 "element is locked, return previous return %s",
2552 gst_element_state_change_return_get_name (ret));
2553 GST_STATE_UNLOCK (element);
2558 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2559 "skipping transition from %s to %s",
2560 gst_element_state_get_name (child_current),
2561 gst_element_state_get_name (next));
2562 GST_STATE_UNLOCK (element);
2567 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2568 GST_OBJECT_UNLOCK (bin);
2569 GST_STATE_UNLOCK (element);
2570 return GST_STATE_CHANGE_ASYNC;
2574 /* gst_iterator_fold functions for pads_activate
2575 * Stop the iterator if activating one pad failed, but only if that pad
2576 * has not been removed from the element. */
2578 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2580 GstPad *pad = g_value_get_object (vpad);
2581 gboolean cont = TRUE;
2583 if (!gst_pad_set_active (pad, *active)) {
2584 if (GST_PAD_PARENT (pad) != NULL) {
2586 g_value_set_boolean (ret, FALSE);
2593 /* returns false on error or early cutout of the fold, true if all
2594 * pads in @iter were (de)activated successfully. */
2596 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2598 GstIteratorResult ires;
2601 /* no need to unset this later, it's just a boolean */
2602 g_value_init (&ret, G_TYPE_BOOLEAN);
2603 g_value_set_boolean (&ret, TRUE);
2606 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2609 case GST_ITERATOR_RESYNC:
2610 /* need to reset the result again */
2611 g_value_set_boolean (&ret, TRUE);
2612 gst_iterator_resync (iter);
2614 case GST_ITERATOR_DONE:
2615 /* all pads iterated, return collected value */
2618 /* iterator returned _ERROR or premature end with _OK,
2619 * mark an error and exit */
2620 g_value_set_boolean (&ret, FALSE);
2625 /* return collected value */
2626 return g_value_get_boolean (&ret);
2629 /* is called with STATE_LOCK
2632 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2637 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2639 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2640 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2641 gst_iterator_free (iter);
2642 if (G_UNLIKELY (!fold_ok))
2645 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2652 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2658 * gst_bin_recalculate_latency:
2661 * Query @bin for the current latency using and reconfigures this latency to all the
2662 * elements with a LATENCY event.
2664 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2665 * is posted on the bus.
2667 * This function simply emits the 'do-latency' signal so any custom latency
2668 * calculations will be performed.
2670 * Returns: %TRUE if the latency could be queried and reconfigured.
2673 gst_bin_recalculate_latency (GstBin * bin)
2677 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2678 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2684 gst_bin_do_latency_func (GstBin * bin)
2687 GstElement *element;
2688 GstClockTime min_latency, max_latency;
2691 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2693 element = GST_ELEMENT_CAST (bin);
2695 GST_DEBUG_OBJECT (element, "querying latency");
2697 query = gst_query_new_latency ();
2698 if ((res = gst_element_query (element, query))) {
2701 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2703 GST_DEBUG_OBJECT (element,
2704 "got min latency %" GST_TIME_FORMAT ", max latency %"
2705 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2706 GST_TIME_ARGS (max_latency), live);
2708 if (max_latency < min_latency) {
2709 /* this is an impossible situation, some parts of the pipeline might not
2710 * work correctly. We post a warning for now. */
2711 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2712 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2713 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2714 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2717 /* configure latency on elements */
2718 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2720 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2721 GST_TIME_ARGS (min_latency));
2723 GST_WARNING_OBJECT (element,
2724 "did not really configure latency of %" GST_TIME_FORMAT,
2725 GST_TIME_ARGS (min_latency));
2728 /* this is not a real problem, we just don't configure any latency. */
2729 GST_WARNING_OBJECT (element, "failed to query latency");
2731 gst_query_unref (query);
2737 gst_bin_post_message (GstElement * element, GstMessage * msg)
2739 GstElementClass *pklass = (GstElementClass *) parent_class;
2742 ret = pklass->post_message (element, gst_message_ref (msg));
2744 if (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_STATE_CHANGED &&
2745 GST_MESSAGE_SRC (msg) == GST_OBJECT_CAST (element)) {
2746 GstState newstate, pending;
2748 gst_message_parse_state_changed (msg, NULL, &newstate, &pending);
2749 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING) {
2750 GST_BIN_CAST (element)->priv->posted_playing = TRUE;
2751 bin_do_eos (GST_BIN_CAST (element));
2753 GST_BIN_CAST (element)->priv->posted_playing = FALSE;
2757 gst_message_unref (msg);
2763 reset_state (const GValue * data, gpointer user_data)
2765 GstElement *e = g_value_get_object (data);
2766 GstState state = GPOINTER_TO_INT (user_data);
2768 if (gst_element_set_state (e, state) == GST_STATE_CHANGE_FAILURE)
2769 GST_WARNING_OBJECT (e, "Failed to switch back down to %s",
2770 gst_element_state_get_name (state));
2773 static GstStateChangeReturn
2774 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2777 GstStateChangeReturn ret;
2778 GstState current, next;
2779 gboolean have_async;
2780 gboolean have_no_preroll;
2781 GstClockTime base_time, start_time;
2784 GValue data = { 0, };
2786 /* we don't need to take the STATE_LOCK, it is already taken */
2787 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2788 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2790 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2791 "changing state of children from %s to %s",
2792 gst_element_state_get_name (current), gst_element_state_get_name (next));
2794 bin = GST_BIN_CAST (element);
2797 case GST_STATE_PLAYING:
2799 gboolean toplevel, asynchandling;
2801 GST_OBJECT_LOCK (bin);
2802 toplevel = BIN_IS_TOPLEVEL (bin);
2803 asynchandling = bin->priv->asynchandling;
2804 GST_OBJECT_UNLOCK (bin);
2807 gst_bin_recalculate_latency (bin);
2809 gst_element_post_message (element,
2810 gst_message_new_latency (GST_OBJECT_CAST (element)));
2813 case GST_STATE_PAUSED:
2814 /* Clear EOS list on next PAUSED */
2815 GST_OBJECT_LOCK (bin);
2816 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2817 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2818 bin->priv->posted_eos = FALSE;
2819 if (current == GST_STATE_READY)
2820 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2821 GST_OBJECT_UNLOCK (bin);
2822 if (current == GST_STATE_READY)
2823 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2824 goto activate_failure;
2826 case GST_STATE_READY:
2827 /* Clear message list on next READY */
2828 GST_OBJECT_LOCK (bin);
2829 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2830 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2831 GST_OBJECT_UNLOCK (bin);
2832 /* We might not have reached PAUSED yet due to async errors,
2833 * make sure to always deactivate the pads nonetheless */
2834 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2835 goto activate_failure;
2837 case GST_STATE_NULL:
2838 /* Clear message list on next NULL */
2839 GST_OBJECT_LOCK (bin);
2840 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2841 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2842 GST_OBJECT_UNLOCK (bin);
2843 if (current == GST_STATE_READY) {
2844 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2845 goto activate_failure;
2852 /* this flag is used to make the async state changes return immediately. We
2853 * don't want them to interfere with this state change */
2854 GST_OBJECT_LOCK (bin);
2855 bin->polling = TRUE;
2856 GST_OBJECT_UNLOCK (bin);
2858 /* iterate in state change order */
2859 it = gst_bin_iterate_sorted (bin);
2861 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2862 * Note how we don't reset this value when a resync happens, the reason being
2863 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2864 * even after a resync when the async element is gone */
2868 /* take base_time */
2869 base_time = gst_element_get_base_time (element);
2870 start_time = gst_element_get_start_time (element);
2872 have_no_preroll = FALSE;
2876 switch (gst_iterator_next (it, &data)) {
2877 case GST_ITERATOR_OK:
2881 child = g_value_get_object (&data);
2883 /* set state and base_time now */
2884 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2888 case GST_STATE_CHANGE_SUCCESS:
2889 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2890 "child '%s' changed state to %d(%s) successfully",
2891 GST_ELEMENT_NAME (child), next,
2892 gst_element_state_get_name (next));
2894 case GST_STATE_CHANGE_ASYNC:
2896 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2897 "child '%s' is changing state asynchronously to %s",
2898 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2902 case GST_STATE_CHANGE_FAILURE:{
2905 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2906 "child '%s' failed to go to state %d(%s)",
2907 GST_ELEMENT_NAME (child),
2908 next, gst_element_state_get_name (next));
2910 /* Only fail if the child is still inside
2911 * this bin. It might've been removed already
2912 * because of the error by the bin subclass
2913 * to ignore the error. */
2914 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2915 if (parent == GST_OBJECT_CAST (element)) {
2916 /* element is still in bin, really error now */
2917 gst_object_unref (parent);
2920 /* child removed from bin, let the resync code redo the state
2922 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2923 "child '%s' was removed from the bin",
2924 GST_ELEMENT_NAME (child));
2927 gst_object_unref (parent);
2931 case GST_STATE_CHANGE_NO_PREROLL:
2932 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2933 "child '%s' changed state to %d(%s) successfully without preroll",
2934 GST_ELEMENT_NAME (child), next,
2935 gst_element_state_get_name (next));
2936 have_no_preroll = TRUE;
2939 g_assert_not_reached ();
2942 g_value_reset (&data);
2945 case GST_ITERATOR_RESYNC:
2946 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
2947 gst_iterator_resync (it);
2950 case GST_ITERATOR_DONE:
2951 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
2957 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
2958 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
2961 if (have_no_preroll) {
2962 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2963 "we have NO_PREROLL elements %s -> NO_PREROLL",
2964 gst_element_state_change_return_get_name (ret));
2965 ret = GST_STATE_CHANGE_NO_PREROLL;
2966 } else if (have_async) {
2967 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2968 "we have ASYNC elements %s -> ASYNC",
2969 gst_element_state_change_return_get_name (ret));
2970 ret = GST_STATE_CHANGE_ASYNC;
2974 g_value_unset (&data);
2975 gst_iterator_free (it);
2977 GST_OBJECT_LOCK (bin);
2978 bin->polling = FALSE;
2979 /* it's possible that we did not get ASYNC from the children while the bin is
2980 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
2981 * itself as the source. In that case we still want to check if the state
2982 * change completed. */
2983 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
2984 /* no element returned ASYNC and there are no pending async_done messages,
2985 * we can just complete. */
2986 GST_DEBUG_OBJECT (bin, "no async elements");
2989 /* when we get here an ASYNC element was found */
2990 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
2991 /* we ignore ASYNC state changes when we go to READY or NULL */
2992 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
2993 gst_element_state_get_name (GST_STATE_TARGET (bin)));
2997 GST_DEBUG_OBJECT (bin, "check async elements");
2998 /* check if all elements managed to commit their state already */
2999 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3000 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
3001 * all the elements commited their state while we were doing the state
3002 * change. We will still return ASYNC for consistency but we commit the
3003 * state already so that a _get_state() will return immediately. */
3004 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3006 GST_DEBUG_OBJECT (bin, "async elements commited");
3007 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
3008 GST_CLOCK_TIME_NONE);
3012 bin->priv->pending_async_done = FALSE;
3013 GST_OBJECT_UNLOCK (bin);
3015 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
3016 "done changing bin's state from %s to %s, now in %s, ret %s",
3017 gst_element_state_get_name (current),
3018 gst_element_state_get_name (next),
3019 gst_element_state_get_name (GST_STATE (element)),
3020 gst_element_state_change_return_get_name (ret));
3027 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
3028 "failure (de)activating src pads");
3029 return GST_STATE_CHANGE_FAILURE;
3034 if (current < next) {
3035 GstIterator *it = gst_bin_iterate_sorted (GST_BIN (element));
3036 GstIteratorResult ret;
3038 GST_DEBUG_OBJECT (element,
3039 "Bin failed to change state, switching children back to %s",
3040 gst_element_state_get_name (current));
3043 gst_iterator_foreach (it, &reset_state, GINT_TO_POINTER (current));
3044 } while (ret == GST_ITERATOR_RESYNC);
3045 gst_iterator_free (it);
3052 * This function is a utility event handler for seek events.
3053 * It will send the event to all sinks or sources and appropriate
3054 * ghost pads depending on the event-direction.
3056 * Applications are free to override this behaviour and
3057 * implement their own seek handler, but this will work for
3058 * pretty much all cases in practice.
3061 gst_bin_send_event (GstElement * element, GstEvent * event)
3063 GstBin *bin = GST_BIN_CAST (element);
3065 gboolean res = TRUE;
3066 gboolean done = FALSE;
3067 GValue data = { 0, };
3069 if (GST_EVENT_IS_DOWNSTREAM (event)) {
3070 iter = gst_bin_iterate_sources (bin);
3071 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
3072 GST_EVENT_TYPE_NAME (event));
3074 iter = gst_bin_iterate_sinks (bin);
3075 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
3076 GST_EVENT_TYPE_NAME (event));
3080 switch (gst_iterator_next (iter, &data)) {
3081 case GST_ITERATOR_OK:
3083 GstElement *child = g_value_get_object (&data);
3085 gst_event_ref (event);
3086 res &= gst_element_send_event (child, event);
3088 GST_LOG_OBJECT (child, "After handling %s event: %d",
3089 GST_EVENT_TYPE_NAME (event), res);
3091 g_value_reset (&data);
3094 case GST_ITERATOR_RESYNC:
3095 gst_iterator_resync (iter);
3098 case GST_ITERATOR_DONE:
3101 case GST_ITERATOR_ERROR:
3102 g_assert_not_reached ();
3106 g_value_unset (&data);
3107 gst_iterator_free (iter);
3109 if (GST_EVENT_IS_DOWNSTREAM (event)) {
3110 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
3111 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
3112 GST_EVENT_TYPE_NAME (event));
3114 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
3115 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
3116 GST_EVENT_TYPE_NAME (event));
3121 switch (gst_iterator_next (iter, &data)) {
3122 case GST_ITERATOR_OK:
3124 GstPad *pad = g_value_get_object (&data);
3126 gst_event_ref (event);
3127 res &= gst_pad_send_event (pad, event);
3128 GST_LOG_OBJECT (pad, "After handling %s event: %d",
3129 GST_EVENT_TYPE_NAME (event), res);
3132 case GST_ITERATOR_RESYNC:
3133 gst_iterator_resync (iter);
3136 case GST_ITERATOR_DONE:
3139 case GST_ITERATOR_ERROR:
3140 g_assert_not_reached ();
3145 g_value_unset (&data);
3146 gst_iterator_free (iter);
3147 gst_event_unref (event);
3152 /* this is the function called by the threadpool. When async elements commit
3153 * their state, this function will attempt to bring the bin to the next state.
3156 gst_bin_continue_func (GstBin * bin, BinContinueData * data)
3158 GstState current, next, pending;
3159 GstStateChange transition;
3161 pending = data->pending;
3163 GST_DEBUG_OBJECT (bin, "waiting for state lock");
3164 GST_STATE_LOCK (bin);
3166 GST_DEBUG_OBJECT (bin, "doing state continue");
3167 GST_OBJECT_LOCK (bin);
3169 /* if a new state change happened after this thread was scheduled, we return
3171 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
3174 current = GST_STATE (bin);
3175 next = GST_STATE_GET_NEXT (current, pending);
3176 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
3178 GST_STATE_NEXT (bin) = next;
3179 GST_STATE_PENDING (bin) = pending;
3181 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3182 GST_OBJECT_UNLOCK (bin);
3184 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3185 "continue state change %s to %s, final %s",
3186 gst_element_state_get_name (current),
3187 gst_element_state_get_name (next), gst_element_state_get_name (pending));
3189 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
3191 GST_STATE_UNLOCK (bin);
3192 GST_DEBUG_OBJECT (bin, "state continue done");
3198 GST_OBJECT_UNLOCK (bin);
3199 GST_STATE_UNLOCK (bin);
3200 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
3205 static GstBusSyncReply
3206 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
3208 GstBinClass *bclass;
3210 bclass = GST_BIN_GET_CLASS (bin);
3211 if (bclass->handle_message)
3212 bclass->handle_message (bin, message);
3214 gst_message_unref (message);
3216 return GST_BUS_DROP;
3220 free_bin_continue_data (BinContinueData * data)
3222 g_slice_free (BinContinueData, data);
3226 bin_push_state_continue (GstBin * bin, BinContinueData * data)
3228 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
3229 gst_element_call_async (GST_ELEMENT_CAST (bin),
3230 (GstElementCallAsyncFunc) gst_bin_continue_func, data,
3231 (GDestroyNotify) free_bin_continue_data);
3234 /* an element started an async state change, if we were not busy with a state
3235 * change, we perform a lost state.
3236 * This function is called with the OBJECT lock.
3239 bin_handle_async_start (GstBin * bin)
3241 GstState old_state, new_state;
3243 GstMessage *amessage = NULL;
3245 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3248 /* get our toplevel state */
3249 toplevel = BIN_IS_TOPLEVEL (bin);
3251 /* prepare an ASYNC_START message, we always post the start message even if we
3252 * are busy with a state change or when we are NO_PREROLL. */
3254 /* non toplevel bin, prepare async-start for the parent */
3255 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
3257 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
3260 /* async starts are ignored when we are NO_PREROLL */
3261 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
3262 goto was_no_preroll;
3264 old_state = GST_STATE (bin);
3266 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
3267 * PLAYING after optionally redistributing the base_time. */
3268 if (old_state > GST_STATE_PAUSED)
3269 new_state = GST_STATE_PAUSED;
3271 new_state = old_state;
3273 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3274 "lost state of %s, new %s", gst_element_state_get_name (old_state),
3275 gst_element_state_get_name (new_state));
3277 GST_STATE (bin) = new_state;
3278 GST_STATE_NEXT (bin) = new_state;
3279 GST_STATE_PENDING (bin) = new_state;
3280 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3281 GST_OBJECT_UNLOCK (bin);
3284 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
3289 /* post our ASYNC_START. */
3290 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
3291 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3293 GST_OBJECT_LOCK (bin);
3299 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3304 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3305 GST_OBJECT_UNLOCK (bin);
3310 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3311 GST_OBJECT_UNLOCK (bin);
3316 /* this function is called when there are no more async elements in the bin. We
3317 * post a state changed message and an ASYNC_DONE message.
3318 * This function is called with the OBJECT lock.
3321 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3322 gboolean flag_pending, GstClockTime running_time)
3324 GstState current, pending, target;
3325 GstStateChangeReturn old_ret;
3326 GstState old_state, old_next;
3327 gboolean toplevel, state_changed = FALSE;
3328 GstMessage *amessage = NULL;
3329 BinContinueData *cont = NULL;
3331 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3334 pending = GST_STATE_PENDING (bin);
3339 /* check if there is something to commit */
3340 if (pending == GST_STATE_VOID_PENDING)
3341 goto nothing_pending;
3343 old_ret = GST_STATE_RETURN (bin);
3344 GST_STATE_RETURN (bin) = ret;
3346 /* move to the next target state */
3347 target = GST_STATE_TARGET (bin);
3348 pending = GST_STATE_PENDING (bin) = target;
3350 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3352 old_state = GST_STATE (bin);
3353 /* this is the state we should go to next */
3354 old_next = GST_STATE_NEXT (bin);
3356 if (old_next != GST_STATE_PLAYING) {
3357 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3358 "committing state from %s to %s, old pending %s",
3359 gst_element_state_get_name (old_state),
3360 gst_element_state_get_name (old_next),
3361 gst_element_state_get_name (pending));
3363 /* update current state */
3364 current = GST_STATE (bin) = old_next;
3366 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3367 "setting state from %s to %s, pending %s",
3368 gst_element_state_get_name (old_state),
3369 gst_element_state_get_name (old_state),
3370 gst_element_state_get_name (pending));
3371 current = old_state;
3374 /* get our toplevel state */
3375 toplevel = BIN_IS_TOPLEVEL (bin);
3377 /* see if we reached the final state. If we are not toplevel, we also have to
3378 * stop here, the parent will continue our state. */
3379 if ((pending == current) || !toplevel) {
3380 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3381 "completed state change, pending VOID");
3383 /* mark VOID pending */
3384 pending = GST_STATE_VOID_PENDING;
3385 GST_STATE_PENDING (bin) = pending;
3386 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3388 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3389 "continue state change, pending %s",
3390 gst_element_state_get_name (pending));
3392 cont = g_slice_new (BinContinueData);
3394 /* cookie to detect concurrent state change */
3395 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3396 /* pending target state */
3397 cont->pending = pending;
3399 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3400 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3403 if (old_next != GST_STATE_PLAYING) {
3404 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3405 state_changed = TRUE;
3408 GST_OBJECT_UNLOCK (bin);
3410 if (state_changed) {
3411 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3415 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3416 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3417 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3420 GST_OBJECT_LOCK (bin);
3422 /* toplevel, start continue state */
3423 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3424 bin_push_state_continue (bin, cont);
3426 GST_DEBUG_OBJECT (bin, "state change complete");
3427 GST_STATE_BROADCAST (bin);
3433 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3438 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3439 /* if we were busy with a state change and we are requested to flag a
3440 * pending async done, we do so here */
3442 bin->priv->pending_async_done = TRUE;
3447 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3453 bin_do_eos (GstBin * bin)
3458 GST_OBJECT_LOCK (bin);
3459 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3460 * (or we're doing playing to playing and noone else will trigger posting
3461 * EOS for us) we forward the EOS message to the parent bin or application
3463 eos = GST_STATE (bin) == GST_STATE_PLAYING
3464 && (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING ||
3465 GST_STATE_PENDING (bin) == GST_STATE_PLAYING)
3466 && bin->priv->posted_playing && is_eos (bin, &seqnum);
3467 GST_OBJECT_UNLOCK (bin);
3470 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3472 GstMessage *tmessage;
3474 /* Clear out any further messages, and reset posted_eos so we can
3475 detect any new EOS that happens (eg, after a seek). Since all
3476 sinks have now posted an EOS, there will be no further EOS events
3477 seen unless there is a new logical EOS */
3478 GST_OBJECT_LOCK (bin);
3479 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3480 bin->priv->posted_eos = FALSE;
3481 GST_OBJECT_UNLOCK (bin);
3483 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3484 gst_message_set_seqnum (tmessage, seqnum);
3485 GST_DEBUG_OBJECT (bin,
3486 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3487 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3489 GST_LOG_OBJECT (bin, "Not forwarding EOS due to in progress state change, "
3490 " or already posted, or waiting for more EOS");
3495 bin_do_stream_start (GstBin * bin)
3498 gboolean stream_start;
3499 gboolean have_group_id = FALSE;
3502 GST_OBJECT_LOCK (bin);
3503 /* If all sinks are STREAM_START we forward the STREAM_START message
3504 * to the parent bin or application
3506 stream_start = is_stream_start (bin, &seqnum, &have_group_id, &group_id);
3507 GST_OBJECT_UNLOCK (bin);
3510 GstMessage *tmessage;
3512 GST_OBJECT_LOCK (bin);
3513 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3514 GST_OBJECT_UNLOCK (bin);
3516 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3517 gst_message_set_seqnum (tmessage, seqnum);
3519 gst_message_set_group_id (tmessage, group_id);
3521 GST_DEBUG_OBJECT (bin,
3522 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3524 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3528 /* must be called without the object lock as it posts messages */
3530 bin_do_message_forward (GstBin * bin, GstMessage * message)
3532 if (bin->priv->message_forward) {
3533 GstMessage *forwarded;
3535 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3536 GST_MESSAGE_TYPE_NAME (message));
3538 /* we need to convert these messages to element messages so that our parent
3539 * bin can easily ignore them and so that the application can easily
3540 * distinguish between the internally forwarded and the real messages. */
3541 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3542 gst_structure_new ("GstBinForwarded",
3543 "message", GST_TYPE_MESSAGE, message, NULL));
3545 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3550 gst_bin_update_context (GstBin * bin, GstContext * context)
3552 GST_OBJECT_LOCK (bin);
3553 gst_bin_update_context_unlocked (bin, context);
3554 GST_OBJECT_UNLOCK (bin);
3558 gst_bin_update_context_unlocked (GstBin * bin, GstContext * context)
3560 const gchar *context_type;
3561 GList *l, **contexts;
3563 contexts = &GST_ELEMENT_CAST (bin)->contexts;
3564 context_type = gst_context_get_context_type (context);
3566 GST_DEBUG_OBJECT (bin, "set context %p %" GST_PTR_FORMAT, context,
3567 gst_context_get_structure (context));
3568 for (l = *contexts; l; l = l->next) {
3569 GstContext *tmp = l->data;
3570 const gchar *tmp_type = gst_context_get_context_type (tmp);
3572 /* Always store newest context but never replace
3573 * a persistent one by a non-persistent one */
3574 if (strcmp (context_type, tmp_type) == 0 &&
3575 (gst_context_is_persistent (context) ||
3576 !gst_context_is_persistent (tmp))) {
3577 gst_context_replace ((GstContext **) & l->data, context);
3581 /* Not found? Add */
3583 *contexts = g_list_prepend (*contexts, gst_context_ref (context));
3587 /* handle child messages:
3589 * This method is called synchronously when a child posts a message on
3592 * GST_MESSAGE_EOS: This message is only posted by sinks
3593 * in the PLAYING state. If all sinks posted the EOS message, post
3596 * GST_MESSAGE_STATE_DIRTY: Deprecated
3598 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3599 * element posts segment_start twice, only the last message is kept.
3601 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3602 * with the segment_done message. If there are no more segment_start
3603 * messages, post segment_done message upwards.
3605 * GST_MESSAGE_DURATION_CHANGED: clear any cached durations.
3606 * Whenever someone performs a duration query on the bin, we store the
3607 * result so we can answer it quicker the next time. Any element that
3608 * changes its duration marks our cached values invalid.
3609 * This message is also posted upwards. This is currently disabled
3610 * because too many elements don't post DURATION_CHANGED messages when
3611 * the duration changes.
3613 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3614 * can no longer provide a clock. The default bin behaviour is to
3615 * check if the lost clock was the one provided by the bin. If so and
3616 * we are currently in the PLAYING state, we forward the message to
3618 * This message is also generated when we remove a clock provider from
3619 * a bin. If this message is received by the application, it should
3620 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3621 * and a new base_time distribution.
3623 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3624 * can provide a clock. This mostly happens when we add a new clock
3625 * provider to the bin. The default behaviour of the bin is to mark the
3626 * currently selected clock as dirty, which will perform a clock
3627 * recalculation the next time we are asked to provide a clock.
3628 * This message is never sent to the application but is forwarded to
3631 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3632 * the state of the element and the fact that the element will need a
3633 * new base_time. This message is not forwarded to the application.
3635 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3636 * element when it posted ASYNC_START. If all elements are done, post a
3637 * ASYNC_DONE message to the parent.
3639 * OTHER: post upwards.
3642 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3645 GstMessageType type;
3646 GstMessage *tmessage;
3649 src = GST_MESSAGE_SRC (message);
3650 type = GST_MESSAGE_TYPE (message);
3652 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3653 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3654 GST_MESSAGE_TYPE_NAME (message));
3657 case GST_MESSAGE_ERROR:
3659 GST_OBJECT_LOCK (bin);
3661 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3662 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3663 GST_STATE_BROADCAST (bin);
3664 GST_OBJECT_UNLOCK (bin);
3668 case GST_MESSAGE_EOS:
3671 /* collect all eos messages from the children */
3672 bin_do_message_forward (bin, message);
3673 GST_OBJECT_LOCK (bin);
3674 /* ref message for future use */
3675 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3676 GST_OBJECT_UNLOCK (bin);
3681 case GST_MESSAGE_STREAM_START:
3684 /* collect all stream_start messages from the children */
3685 GST_OBJECT_LOCK (bin);
3686 /* ref message for future use */
3687 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3688 GST_OBJECT_UNLOCK (bin);
3690 bin_do_stream_start (bin);
3693 case GST_MESSAGE_STATE_DIRTY:
3695 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3698 gst_message_unref (message);
3701 case GST_MESSAGE_SEGMENT_START:{
3702 gboolean post = FALSE;
3706 gst_message_parse_segment_start (message, &format, &position);
3707 seqnum = gst_message_get_seqnum (message);
3709 bin_do_message_forward (bin, message);
3711 GST_OBJECT_LOCK (bin);
3712 /* if this is the first segment-start, post to parent but not to the
3714 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3715 (GST_OBJECT_PARENT (bin) != NULL)) {
3718 /* replace any previous segment_start message from this source
3719 * with the new segment start message */
3720 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3721 GST_OBJECT_UNLOCK (bin);
3723 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3725 gst_message_set_seqnum (tmessage, seqnum);
3727 /* post segment start with initial format and position. */
3728 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3730 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3734 case GST_MESSAGE_SEGMENT_DONE:
3736 gboolean post = FALSE;
3740 gst_message_parse_segment_done (message, &format, &position);
3741 seqnum = gst_message_get_seqnum (message);
3743 bin_do_message_forward (bin, message);
3745 GST_OBJECT_LOCK (bin);
3746 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3747 /* if there are no more segment_start messages, everybody posted
3748 * a segment_done and we can post one on the bus. */
3750 /* we don't care who still has a pending segment start */
3751 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3754 /* remove all old segment_done messages */
3755 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3757 GST_OBJECT_UNLOCK (bin);
3759 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3761 gst_message_set_seqnum (tmessage, seqnum);
3763 /* post segment done with latest format and position. */
3764 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3766 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3770 case GST_MESSAGE_DURATION_CHANGED:
3772 /* FIXME: remove all cached durations, next time somebody asks
3773 * for duration, we will recalculate. */
3775 GST_OBJECT_LOCK (bin);
3776 bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION_CHANGED);
3777 GST_OBJECT_UNLOCK (bin);
3781 case GST_MESSAGE_CLOCK_LOST:
3783 GstClock **provided_clock_p;
3784 GstElement **clock_provider_p;
3785 gboolean playing, toplevel, provided, forward;
3788 gst_message_parse_clock_lost (message, &clock);
3790 GST_OBJECT_LOCK (bin);
3791 bin->clock_dirty = TRUE;
3792 /* if we lost the clock that we provided, post to parent but
3793 * only if we are not a top-level bin or PLAYING.
3794 * The reason for this is that applications should be able
3795 * to PAUSE/PLAY if they receive this message without worrying
3796 * about the state of the pipeline. */
3797 provided = (clock == bin->provided_clock);
3798 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3799 toplevel = GST_OBJECT_PARENT (bin) == NULL;
3800 forward = provided && (playing || !toplevel);
3802 GST_DEBUG_OBJECT (bin,
3803 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3804 bin->provided_clock, bin->clock_provider);
3805 provided_clock_p = &bin->provided_clock;
3806 clock_provider_p = &bin->clock_provider;
3807 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3808 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3810 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3811 provided, playing, forward);
3812 GST_OBJECT_UNLOCK (bin);
3818 gst_message_unref (message);
3821 case GST_MESSAGE_CLOCK_PROVIDE:
3825 GST_OBJECT_LOCK (bin);
3826 bin->clock_dirty = TRUE;
3827 /* a new clock is available, post to parent but not
3828 * to the application */
3829 forward = GST_OBJECT_PARENT (bin) != NULL;
3830 GST_OBJECT_UNLOCK (bin);
3836 gst_message_unref (message);
3839 case GST_MESSAGE_ASYNC_START:
3843 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3844 src ? GST_OBJECT_NAME (src) : "(NULL)");
3846 bin_do_message_forward (bin, message);
3848 GST_OBJECT_LOCK (bin);
3849 /* we ignore the message if we are going to <= READY */
3850 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3851 goto ignore_start_message;
3853 /* takes ownership of the message */
3854 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3856 bin_handle_async_start (bin);
3857 GST_OBJECT_UNLOCK (bin);
3860 ignore_start_message:
3862 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3863 gst_element_state_get_name (target));
3864 GST_OBJECT_UNLOCK (bin);
3865 gst_message_unref (message);
3869 case GST_MESSAGE_ASYNC_DONE:
3871 GstClockTime running_time;
3874 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3875 src ? GST_OBJECT_NAME (src) : "(NULL)");
3877 gst_message_parse_async_done (message, &running_time);
3879 bin_do_message_forward (bin, message);
3881 GST_OBJECT_LOCK (bin);
3882 /* ignore messages if we are shutting down */
3883 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3884 goto ignore_done_message;
3886 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3887 /* if there are no more ASYNC_START messages, everybody posted
3888 * a ASYNC_DONE and we can post one on the bus. When checking, we
3889 * don't care who still has a pending ASYNC_START */
3890 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3891 /* nothing found, remove all old ASYNC_DONE messages */
3892 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3894 GST_DEBUG_OBJECT (bin, "async elements commited");
3895 /* when we get an async done message when a state change was busy, we
3896 * need to set the pending_done flag so that at the end of the state
3897 * change we can see if we need to verify pending async elements, hence
3898 * the TRUE argument here. */
3899 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3902 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3904 GST_OBJECT_UNLOCK (bin);
3907 ignore_done_message:
3909 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3910 gst_element_state_get_name (target));
3911 GST_OBJECT_UNLOCK (bin);
3912 gst_message_unref (message);
3916 case GST_MESSAGE_STRUCTURE_CHANGE:
3920 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3922 GST_OBJECT_LOCK (bin);
3924 /* while the pad is busy, avoid following it when doing state changes.
3925 * Don't update the cookie yet, we will do that after the structure
3926 * change finished and we are ready to inspect the new updated
3928 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3931 /* a pad link/unlink ended, signal the state change iterator that we
3932 * need to resync by updating the structure_cookie. */
3933 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3934 GST_MESSAGE_STRUCTURE_CHANGE);
3935 if (!GST_BIN_IS_NO_RESYNC (bin))
3936 bin->priv->structure_cookie++;
3938 GST_OBJECT_UNLOCK (bin);
3941 gst_message_unref (message);
3945 case GST_MESSAGE_NEED_CONTEXT:{
3946 const gchar *context_type;
3947 GList *l, *contexts;
3949 gst_message_parse_context_type (message, &context_type);
3950 GST_OBJECT_LOCK (bin);
3951 contexts = GST_ELEMENT_CAST (bin)->contexts;
3952 GST_LOG_OBJECT (bin, "got need-context message type: %s", context_type);
3953 for (l = contexts; l; l = l->next) {
3954 GstContext *tmp = l->data;
3955 const gchar *tmp_type = gst_context_get_context_type (tmp);
3957 if (strcmp (context_type, tmp_type) == 0) {
3958 gst_element_set_context (GST_ELEMENT (src), l->data);
3962 GST_OBJECT_UNLOCK (bin);
3964 /* Forward if we couldn't answer the message */
3968 gst_message_unref (message);
3973 case GST_MESSAGE_HAVE_CONTEXT:{
3974 GstContext *context;
3976 gst_message_parse_have_context (message, &context);
3977 gst_bin_update_context (bin, context);
3978 gst_context_unref (context);
3990 /* Send all other messages upward */
3991 GST_DEBUG_OBJECT (bin, "posting message upward");
3992 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
3997 /* generic struct passed to all query fold methods */
4006 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
4007 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
4009 /* for duration/position we collect all durations/positions and take
4010 * the MAX of all valid results */
4012 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
4020 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4022 gboolean res = FALSE;
4023 GstObject *item = g_value_get_object (vitem);
4024 if (GST_IS_PAD (item))
4025 res = gst_pad_query (GST_PAD (item), fold->query);
4027 res = gst_element_query (GST_ELEMENT (item), fold->query);
4032 g_value_set_boolean (ret, TRUE);
4034 gst_query_parse_duration (fold->query, NULL, &duration);
4036 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
4038 if (duration == -1) {
4039 /* duration query succeeded, but duration is unknown */
4044 if (duration > fold->max)
4045 fold->max = duration;
4052 bin_query_duration_done (GstBin * bin, QueryFold * fold)
4056 gst_query_parse_duration (fold->query, &format, NULL);
4057 /* store max in query result */
4058 gst_query_set_duration (fold->query, format, fold->max);
4060 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
4062 /* FIXME: re-implement duration caching */
4065 GST_OBJECT_LOCK (bin);
4066 bin->messages = g_list_prepend (bin->messages,
4067 gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
4068 GST_OBJECT_UNLOCK (bin);
4073 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4075 gboolean res = FALSE;
4076 GstObject *item = g_value_get_object (vitem);
4077 if (GST_IS_PAD (item))
4078 res = gst_pad_query (GST_PAD (item), fold->query);
4080 res = gst_element_query (GST_ELEMENT (item), fold->query);
4085 g_value_set_boolean (ret, TRUE);
4087 gst_query_parse_position (fold->query, NULL, &position);
4089 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
4091 if (position > fold->max)
4092 fold->max = position;
4099 bin_query_position_done (GstBin * bin, QueryFold * fold)
4103 gst_query_parse_position (fold->query, &format, NULL);
4104 /* store max in query result */
4105 gst_query_set_position (fold->query, format, fold->max);
4107 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
4111 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4113 gboolean res = FALSE;
4114 GstObject *item = g_value_get_object (vitem);
4115 if (GST_IS_PAD (item))
4116 res = gst_pad_query (GST_PAD (item), fold->query);
4118 res = gst_element_query (GST_ELEMENT (item), fold->query);
4120 GstClockTime min, max;
4123 gst_query_parse_latency (fold->query, &live, &min, &max);
4125 GST_DEBUG_OBJECT (item,
4126 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
4127 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
4129 /* for the combined latency we collect the MAX of all min latencies and
4130 * the MIN of all max latencies */
4132 if (min > fold->min)
4134 if (fold->max == -1)
4136 else if (max < fold->max)
4142 g_value_set_boolean (ret, FALSE);
4143 GST_DEBUG_OBJECT (item, "failed query");
4150 bin_query_latency_done (GstBin * bin, QueryFold * fold)
4152 /* store max in query result */
4153 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
4155 GST_DEBUG_OBJECT (bin,
4156 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
4157 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
4161 /* generic fold, return first valid result */
4163 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4165 gboolean res = FALSE;
4166 GstObject *item = g_value_get_object (vitem);
4167 if (GST_IS_PAD (item))
4168 res = gst_pad_query (GST_PAD (item), fold->query);
4170 res = gst_element_query (GST_ELEMENT (item), fold->query);
4172 g_value_set_boolean (ret, TRUE);
4173 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
4176 /* and stop as soon as we have a valid result */
4180 /* Perform a query iteration for the given bin. The query is stored in
4181 * QueryFold and iter should be either a GstPad iterator or a
4182 * GstElement iterator. */
4184 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
4185 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
4186 QueryFold * fold_data, gboolean default_return)
4188 gboolean res = default_return;
4190 /* set the result of the query to FALSE initially */
4191 g_value_init (&ret, G_TYPE_BOOLEAN);
4192 g_value_set_boolean (&ret, res);
4195 GstIteratorResult ires;
4197 ires = gst_iterator_fold (iter, fold_func, &ret, fold_data);
4200 case GST_ITERATOR_RESYNC:
4201 gst_iterator_resync (iter);
4203 fold_init (bin, fold_data);
4204 g_value_set_boolean (&ret, res);
4206 case GST_ITERATOR_OK:
4207 case GST_ITERATOR_DONE:
4208 res = g_value_get_boolean (&ret);
4209 if (fold_done != NULL && res)
4210 fold_done (bin, fold_data);
4222 gst_bin_query (GstElement * element, GstQuery * query)
4224 GstBin *bin = GST_BIN_CAST (element);
4226 gboolean default_return = FALSE;
4227 gboolean res = FALSE;
4228 gboolean src_pads_query_result = FALSE;
4229 GstIteratorFoldFunction fold_func;
4230 QueryInitFunction fold_init = NULL;
4231 QueryDoneFunction fold_done = NULL;
4232 QueryFold fold_data;
4234 switch (GST_QUERY_TYPE (query)) {
4235 case GST_QUERY_DURATION:
4237 /* FIXME: implement duration caching in GstBin again */
4242 gst_query_parse_duration (query, &qformat, NULL);
4244 /* find cached duration query */
4245 GST_OBJECT_LOCK (bin);
4246 for (cached = bin->messages; cached; cached = g_list_next (cached)) {
4247 GstMessage *message = (GstMessage *) cached->data;
4249 if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION_CHANGED &&
4250 GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
4254 gst_message_parse_duration (message, &format, &duration);
4256 /* if cached same format, copy duration in query result */
4257 if (format == qformat) {
4258 GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
4260 GST_OBJECT_UNLOCK (bin);
4262 gst_query_set_duration (query, qformat, duration);
4268 GST_OBJECT_UNLOCK (bin);
4270 GST_FIXME ("implement duration caching in GstBin again");
4272 /* no cached value found, iterate and collect durations */
4273 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
4274 fold_init = bin_query_min_max_init;
4275 fold_done = bin_query_duration_done;
4278 case GST_QUERY_POSITION:
4280 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
4281 fold_init = bin_query_min_max_init;
4282 fold_done = bin_query_position_done;
4285 case GST_QUERY_LATENCY:
4287 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
4288 fold_init = bin_query_min_max_init;
4289 fold_done = bin_query_latency_done;
4290 default_return = TRUE;
4294 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
4298 fold_data.query = query;
4300 iter = gst_bin_iterate_sinks (bin);
4301 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
4302 query, GST_QUERY_TYPE_NAME (query));
4305 fold_init (bin, &fold_data);
4308 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, &fold_data,
4310 gst_iterator_free (iter);
4313 /* Query the source pads of the element */
4314 iter = gst_element_iterate_src_pads (element);
4315 src_pads_query_result =
4316 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
4317 &fold_data, default_return);
4318 gst_iterator_free (iter);
4320 if (src_pads_query_result)
4324 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
4330 set_context (const GValue * item, gpointer user_data)
4332 GstElement *element = g_value_get_object (item);
4334 gst_element_set_context (element, user_data);
4338 gst_bin_set_context (GstElement * element, GstContext * context)
4341 GstIterator *children;
4343 g_return_if_fail (GST_IS_BIN (element));
4345 bin = GST_BIN (element);
4347 GST_ELEMENT_CLASS (parent_class)->set_context (element, context);
4349 children = gst_bin_iterate_elements (bin);
4350 while (gst_iterator_foreach (children, set_context,
4351 context) == GST_ITERATOR_RESYNC)
4352 gst_iterator_resync (children);
4353 gst_iterator_free (children);
4357 compare_name (const GValue * velement, const gchar * name)
4360 GstElement *element = g_value_get_object (velement);
4362 GST_OBJECT_LOCK (element);
4363 eq = strcmp (GST_ELEMENT_NAME (element), name);
4364 GST_OBJECT_UNLOCK (element);
4370 * gst_bin_get_by_name:
4372 * @name: the element name to search for
4374 * Gets the element with the given name from a bin. This
4375 * function recurses into child bins.
4377 * Returns %NULL if no element with the given name is found in the bin.
4379 * MT safe. Caller owns returned reference.
4381 * Returns: (transfer full) (nullable): the #GstElement with the given
4385 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4387 GstIterator *children;
4388 GValue result = { 0, };
4389 GstElement *element;
4392 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4394 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4395 GST_ELEMENT_NAME (bin), name);
4397 children = gst_bin_iterate_recurse (bin);
4398 found = gst_iterator_find_custom (children,
4399 (GCompareFunc) compare_name, &result, (gpointer) name);
4400 gst_iterator_free (children);
4403 element = g_value_dup_object (&result);
4404 g_value_unset (&result);
4413 * gst_bin_get_by_name_recurse_up:
4415 * @name: the element name to search for
4417 * Gets the element with the given name from this bin. If the
4418 * element is not found, a recursion is performed on the parent bin.
4421 * - no element with the given name is found in the bin
4423 * MT safe. Caller owns returned reference.
4425 * Returns: (transfer full) (nullable): the #GstElement with the given
4429 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4433 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4434 g_return_val_if_fail (name != NULL, NULL);
4436 result = gst_bin_get_by_name (bin, name);
4441 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4443 if (GST_IS_BIN (parent)) {
4444 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4446 gst_object_unref (parent);
4454 compare_interface (const GValue * velement, GValue * interface)
4456 GstElement *element = g_value_get_object (velement);
4457 GType interface_type = (GType) g_value_get_pointer (interface);
4460 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4469 * gst_bin_get_by_interface:
4471 * @iface: the #GType of an interface
4473 * Looks for an element inside the bin that implements the given
4474 * interface. If such an element is found, it returns the element.
4475 * You can cast this element to the given interface afterwards. If you want
4476 * all elements that implement the interface, use
4477 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4479 * MT safe. Caller owns returned reference.
4481 * Returns: (transfer full): A #GstElement inside the bin implementing the interface
4484 gst_bin_get_by_interface (GstBin * bin, GType iface)
4486 GstIterator *children;
4487 GValue result = { 0, };
4488 GstElement *element;
4490 GValue viface = { 0, };
4492 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4493 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4495 g_value_init (&viface, G_TYPE_POINTER);
4496 g_value_set_pointer (&viface, (gpointer) iface);
4498 children = gst_bin_iterate_recurse (bin);
4499 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4501 gst_iterator_free (children);
4504 element = g_value_dup_object (&result);
4505 g_value_unset (&result);
4509 g_value_unset (&viface);
4515 * gst_bin_iterate_all_by_interface:
4517 * @iface: the #GType of an interface
4519 * Looks for all elements inside the bin that implements the given
4520 * interface. You can safely cast all returned elements to the given interface.
4521 * The function recurses inside child bins. The iterator will yield a series
4522 * of #GstElement that should be unreffed after use.
4524 * MT safe. Caller owns returned value.
4526 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
4527 * for all elements in the bin implementing the given interface,
4531 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4533 GstIterator *children;
4534 GstIterator *result;
4535 GValue viface = { 0, };
4537 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4538 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4540 g_value_init (&viface, G_TYPE_POINTER);
4541 g_value_set_pointer (&viface, (gpointer) iface);
4543 children = gst_bin_iterate_recurse (bin);
4544 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4547 g_value_unset (&viface);