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;
211 static void gst_bin_dispose (GObject * object);
213 static void gst_bin_set_property (GObject * object, guint prop_id,
214 const GValue * value, GParamSpec * pspec);
215 static void gst_bin_get_property (GObject * object, guint prop_id,
216 GValue * value, GParamSpec * pspec);
218 static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
219 GstStateChange transition);
220 static gboolean gst_bin_post_message (GstElement * element, GstMessage * msg);
221 static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
222 GstState * state, GstState * pending, GstClockTime timeout);
223 static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
224 gboolean flag_pending, GstClockTime running_time);
225 static void bin_handle_async_start (GstBin * bin);
226 static void bin_push_state_continue (BinContinueData * data);
227 static void bin_do_eos (GstBin * bin);
229 static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
230 static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
233 static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
234 static GstIndex *gst_bin_get_index_func (GstElement * element);
237 static GstClock *gst_bin_provide_clock_func (GstElement * element);
238 static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
240 static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
241 static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
242 static GstBusSyncReply bin_bus_handler (GstBus * bus,
243 GstMessage * message, GstBin * bin);
244 static gboolean gst_bin_query (GstElement * element, GstQuery * query);
245 static void gst_bin_set_context (GstElement * element, GstContext * context);
247 static gboolean gst_bin_do_latency_func (GstBin * bin);
249 static void bin_remove_messages (GstBin * bin, GstObject * src,
250 GstMessageType types);
251 static void gst_bin_continue_func (BinContinueData * data);
252 static gint bin_element_is_sink (GstElement * child, GstBin * bin);
253 static gint bin_element_is_src (GstElement * child, GstBin * bin);
255 static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
257 /* Bin signals and properties */
266 #define DEFAULT_ASYNC_HANDLING FALSE
267 #define DEFAULT_MESSAGE_FORWARD FALSE
273 PROP_MESSAGE_FORWARD,
277 static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
279 static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
283 static const GInterfaceInfo iface_info = { \
284 gst_bin_child_proxy_init, \
288 g_type_add_interface_static (g_define_type_id, GST_TYPE_CHILD_PROXY, &iface_info); \
290 GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
291 "debugging info for the 'bin' container element"); \
295 #define gst_bin_parent_class parent_class
296 G_DEFINE_TYPE_WITH_CODE (GstBin, gst_bin, GST_TYPE_ELEMENT, _do_init);
299 gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
305 bin = GST_BIN_CAST (child_proxy);
307 GST_OBJECT_LOCK (bin);
308 if ((res = g_list_nth_data (bin->children, index)))
309 gst_object_ref (res);
310 GST_OBJECT_UNLOCK (bin);
312 return (GObject *) res;
316 gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
321 bin = GST_BIN_CAST (child_proxy);
323 GST_OBJECT_LOCK (bin);
324 num = bin->numchildren;
325 GST_OBJECT_UNLOCK (bin);
331 gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
333 GstChildProxyInterface *iface = g_iface;
335 iface->get_children_count = gst_bin_child_proxy_get_children_count;
336 iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
340 _gst_boolean_accumulator (GSignalInvocationHint * ihint,
341 GValue * return_accu, const GValue * handler_return, gpointer dummy)
345 myboolean = g_value_get_boolean (handler_return);
346 if (!(ihint->run_type & G_SIGNAL_RUN_CLEANUP))
347 g_value_set_boolean (return_accu, myboolean);
349 GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
356 gst_bin_class_init (GstBinClass * klass)
358 GObjectClass *gobject_class;
359 GstElementClass *gstelement_class;
362 gobject_class = (GObjectClass *) klass;
363 gstelement_class = (GstElementClass *) klass;
365 g_type_class_add_private (klass, sizeof (GstBinPrivate));
367 gobject_class->set_property = gst_bin_set_property;
368 gobject_class->get_property = gst_bin_get_property;
371 * GstBin:async-handling:
373 * If set to %TRUE, the bin will handle asynchronous state changes.
374 * This should be used only if the bin subclass is modifying the state
375 * of its children on its own.
377 g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
378 g_param_spec_boolean ("async-handling", "Async Handling",
379 "The bin will handle Asynchronous state changes",
380 DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
383 * GstBin::element-added:
385 * @element: the #GstElement that was added to the bin
387 * Will be emitted after the element was added to the bin.
389 gst_bin_signals[ELEMENT_ADDED] =
390 g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
391 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
392 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
394 * GstBin::element-removed:
396 * @element: the #GstElement that was removed from the bin
398 * Will be emitted after the element was removed from the bin.
400 gst_bin_signals[ELEMENT_REMOVED] =
401 g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
402 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
403 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
405 * GstBin::do-latency:
408 * Will be emitted when the bin needs to perform latency calculations. This
409 * signal is only emitted for toplevel bins or when async-handling is
412 * Only one signal handler is invoked. If no signals are connected, the
413 * default handler is invoked, which will query and distribute the lowest
414 * possible latency to all sinks.
416 * Connect to this signal if the default latency calculations are not
417 * sufficient, like when you need different latencies for different sinks in
420 gst_bin_signals[DO_LATENCY] =
421 g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
422 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
423 _gst_boolean_accumulator, NULL, g_cclosure_marshal_generic,
424 G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
427 * GstBin:message-forward:
429 * Forward all children messages, even those that would normally be filtered by
430 * the bin. This can be interesting when one wants to be notified of the EOS
431 * state of individual elements, for example.
433 * The messages are converted to an ELEMENT message with the bin as the
434 * source. The structure of the message is named 'GstBinForwarded' and contains
435 * a field named 'message' of type GST_TYPE_MESSAGE that contains the original
438 g_object_class_install_property (gobject_class, PROP_MESSAGE_FORWARD,
439 g_param_spec_boolean ("message-forward", "Message Forward",
440 "Forwards all children messages",
441 DEFAULT_MESSAGE_FORWARD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
443 gobject_class->dispose = gst_bin_dispose;
445 gst_element_class_set_static_metadata (gstelement_class, "Generic bin",
447 "Simple container object",
448 "Erik Walthinsen <omega@cse.ogi.edu>,"
449 "Wim Taymans <wim.taymans@gmail.com>");
451 gstelement_class->change_state =
452 GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
453 gstelement_class->post_message = GST_DEBUG_FUNCPTR (gst_bin_post_message);
454 gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
456 gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
457 gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
459 gstelement_class->provide_clock =
460 GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
461 gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
463 gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
464 gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
465 gstelement_class->set_context = GST_DEBUG_FUNCPTR (gst_bin_set_context);
467 klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
468 klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
469 klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
471 klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
473 GST_DEBUG ("creating bin thread pool");
476 g_thread_pool_new ((GFunc) gst_bin_continue_func, NULL, -1, FALSE, &err);
478 g_critical ("could alloc threadpool %s", err->message);
483 gst_bin_init (GstBin * bin)
487 bin->numchildren = 0;
488 bin->children = NULL;
489 bin->children_cookie = 0;
490 bin->messages = NULL;
491 bin->provided_clock = NULL;
492 bin->clock_dirty = FALSE;
494 /* Set up a bus for listening to child elements */
495 bus = g_object_new (GST_TYPE_BUS, "enable-async", FALSE, NULL);
496 bin->child_bus = bus;
497 GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
499 gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin,
502 bin->priv = GST_BIN_GET_PRIVATE (bin);
503 bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
504 bin->priv->structure_cookie = 0;
505 bin->priv->message_forward = DEFAULT_MESSAGE_FORWARD;
509 gst_bin_dispose (GObject * object)
511 GstBin *bin = GST_BIN_CAST (object);
512 GstBus **child_bus_p = &bin->child_bus;
513 GstClock **provided_clock_p = &bin->provided_clock;
514 GstElement **clock_provider_p = &bin->clock_provider;
516 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "dispose");
518 GST_OBJECT_LOCK (object);
519 gst_object_replace ((GstObject **) child_bus_p, NULL);
520 gst_object_replace ((GstObject **) provided_clock_p, NULL);
521 gst_object_replace ((GstObject **) clock_provider_p, NULL);
522 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
523 GST_OBJECT_UNLOCK (object);
525 while (bin->children) {
526 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
528 if (G_UNLIKELY (bin->children != NULL)) {
529 g_critical ("could not remove elements from bin '%s'",
530 GST_STR_NULL (GST_OBJECT_NAME (object)));
533 g_list_free_full (bin->priv->contexts, (GDestroyNotify) gst_context_unref);
535 G_OBJECT_CLASS (parent_class)->dispose (object);
540 * @name: the name of the new bin
542 * Creates a new bin with the given name.
544 * Returns: (transfer floating): a new #GstBin
547 gst_bin_new (const gchar * name)
549 return gst_element_factory_make ("bin", name);
553 gst_bin_set_property (GObject * object, guint prop_id,
554 const GValue * value, GParamSpec * pspec)
558 gstbin = GST_BIN_CAST (object);
561 case PROP_ASYNC_HANDLING:
562 GST_OBJECT_LOCK (gstbin);
563 gstbin->priv->asynchandling = g_value_get_boolean (value);
564 GST_OBJECT_UNLOCK (gstbin);
566 case PROP_MESSAGE_FORWARD:
567 GST_OBJECT_LOCK (gstbin);
568 gstbin->priv->message_forward = g_value_get_boolean (value);
569 GST_OBJECT_UNLOCK (gstbin);
572 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
578 gst_bin_get_property (GObject * object, guint prop_id,
579 GValue * value, GParamSpec * pspec)
583 gstbin = GST_BIN_CAST (object);
586 case PROP_ASYNC_HANDLING:
587 GST_OBJECT_LOCK (gstbin);
588 g_value_set_boolean (value, gstbin->priv->asynchandling);
589 GST_OBJECT_UNLOCK (gstbin);
591 case PROP_MESSAGE_FORWARD:
592 GST_OBJECT_LOCK (gstbin);
593 g_value_set_boolean (value, gstbin->priv->message_forward);
594 GST_OBJECT_UNLOCK (gstbin);
597 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
603 /* return the cached index */
605 gst_bin_get_index_func (GstElement * element)
610 bin = GST_BIN_CAST (element);
612 GST_OBJECT_LOCK (bin);
613 if ((result = bin->priv->index))
614 gst_object_ref (result);
615 GST_OBJECT_UNLOCK (bin);
620 /* set the index on all elements in this bin
625 gst_bin_set_index_func (GstElement * element, GstIndex * index)
631 GValue data = { 0, };
633 bin = GST_BIN_CAST (element);
635 GST_OBJECT_LOCK (bin);
636 old = bin->priv->index;
637 if (G_UNLIKELY (old == index))
640 gst_object_ref (index);
641 bin->priv->index = index;
642 GST_OBJECT_UNLOCK (bin);
645 gst_object_unref (old);
647 it = gst_bin_iterate_elements (bin);
649 /* set the index on all elements in the bin */
652 switch (gst_iterator_next (it, &data)) {
653 case GST_ITERATOR_OK:
655 GstElement *child = g_value_get_object (&data);
657 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
658 GST_ELEMENT_NAME (child));
659 gst_element_set_index (child, index);
661 g_value_reset (&data);
664 case GST_ITERATOR_RESYNC:
665 GST_DEBUG_OBJECT (bin, "iterator doing resync");
666 gst_iterator_resync (it);
669 case GST_ITERATOR_DONE:
670 GST_DEBUG_OBJECT (bin, "iterator done");
675 g_value_unset (&data);
676 gst_iterator_free (it);
681 GST_DEBUG_OBJECT (bin, "index was already set");
682 GST_OBJECT_UNLOCK (bin);
688 /* set the clock on all elements in this bin
693 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
699 GValue data = { 0, };
701 bin = GST_BIN_CAST (element);
703 it = gst_bin_iterate_elements (bin);
707 switch (gst_iterator_next (it, &data)) {
708 case GST_ITERATOR_OK:
710 GstElement *child = g_value_get_object (&data);
712 res &= gst_element_set_clock (child, clock);
714 g_value_reset (&data);
717 case GST_ITERATOR_RESYNC:
718 GST_DEBUG_OBJECT (bin, "iterator doing resync");
719 gst_iterator_resync (it);
723 case GST_ITERATOR_DONE:
724 GST_DEBUG_OBJECT (bin, "iterator done");
729 g_value_unset (&data);
730 gst_iterator_free (it);
733 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
738 /* get the clock for this bin by asking all of the children in this bin
740 * The ref of the returned clock in increased so unref after usage.
742 * We loop the elements in state order and pick the last clock we can
743 * get. This makes sure we get a clock from the source.
748 gst_bin_provide_clock_func (GstElement * element)
750 GstClock *result = NULL;
751 GstElement *provider = NULL;
756 GstClock **provided_clock_p;
757 GstElement **clock_provider_p;
759 bin = GST_BIN_CAST (element);
761 GST_OBJECT_LOCK (bin);
762 if (!bin->clock_dirty)
765 GST_DEBUG_OBJECT (bin, "finding new clock");
767 it = gst_bin_sort_iterator_new (bin);
768 GST_OBJECT_UNLOCK (bin);
772 switch (gst_iterator_next (it, &val)) {
773 case GST_ITERATOR_OK:
775 GstElement *child = g_value_get_object (&val);
778 clock = gst_element_provide_clock (child);
780 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
781 clock, GST_ELEMENT_NAME (child));
783 gst_object_unref (result);
784 gst_object_unref (provider);
787 provider = gst_object_ref (child);
790 g_value_reset (&val);
793 case GST_ITERATOR_RESYNC:
794 gst_iterator_resync (it);
797 case GST_ITERATOR_DONE:
802 g_value_unset (&val);
803 gst_iterator_free (it);
805 GST_OBJECT_LOCK (bin);
806 if (!bin->clock_dirty) {
808 gst_object_unref (provider);
810 gst_object_unref (result);
816 provided_clock_p = &bin->provided_clock;
817 clock_provider_p = &bin->clock_provider;
818 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
819 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
820 bin->clock_dirty = FALSE;
821 GST_DEBUG_OBJECT (bin,
822 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
824 /* Provider is not being returned to caller, just the result */
826 gst_object_unref (provider);
827 GST_OBJECT_UNLOCK (bin);
833 if ((result = bin->provided_clock))
834 gst_object_ref (result);
835 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
836 GST_OBJECT_UNLOCK (bin);
843 * functions for manipulating cached messages
848 GstMessageType types;
851 /* check if a message is of given src and type */
853 message_check (GstMessage * message, MessageFind * target)
858 eq &= GST_MESSAGE_SRC (message) == target->src;
860 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
861 GST_LOG ("looking at message %p: %d", message, eq);
867 find_message (GstBin * bin, GstObject * src, GstMessageType types)
875 result = g_list_find_custom (bin->messages, &find,
876 (GCompareFunc) message_check);
879 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
880 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
883 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
884 #ifndef GST_DISABLE_GST_DEBUG
888 for (i = 0; i < 32; i++)
889 if (types & (1U << i))
890 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1U << i));
898 /* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
901 * A message that is cached and has the same SRC and type is replaced
902 * by the given message.
905 bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
911 if ((src = GST_MESSAGE_SRC (message))) {
912 /* first find the previous message posted by this element */
913 if ((previous = find_message (bin, src, types))) {
914 GstMessage *previous_msg;
916 /* if we found a previous message, replace it */
917 previous_msg = previous->data;
918 previous->data = message;
920 GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
921 GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
922 GST_MESSAGE_TYPE_NAME (message));
924 gst_message_unref (previous_msg);
926 /* keep new message */
927 bin->messages = g_list_prepend (bin->messages, message);
929 GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
930 message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
933 GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
934 GST_MESSAGE_TYPE_NAME (message));
936 gst_message_unref (message);
941 /* with LOCK. Remove all messages of given types */
943 bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
951 for (walk = bin->messages; walk; walk = next) {
952 GstMessage *message = (GstMessage *) walk->data;
954 next = g_list_next (walk);
956 if (message_check (message, &find) == 0) {
957 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
958 "deleting message %p of types 0x%08x", message, types);
959 bin->messages = g_list_delete_link (bin->messages, walk);
960 gst_message_unref (message);
962 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
963 "not deleting message %p of type 0x%08x", message,
964 GST_MESSAGE_TYPE (message));
970 /* Check if the bin is EOS. We do this by scanning all sinks and
971 * checking if they posted an EOS message.
973 * call with bin LOCK */
975 is_eos (GstBin * bin, guint32 * seqnum)
982 for (walk = bin->children; walk; walk = g_list_next (walk)) {
985 element = GST_ELEMENT_CAST (walk->data);
986 if (bin_element_is_sink (element, bin) == 0) {
987 /* check if element posted EOS */
989 find_message (bin, GST_OBJECT_CAST (element), GST_MESSAGE_EOS))) {
990 GST_DEBUG ("sink '%s' posted EOS", GST_ELEMENT_NAME (element));
991 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
994 GST_DEBUG ("sink '%s' did not post EOS yet",
995 GST_ELEMENT_NAME (element));
1001 /* FIXME: Some tests (e.g. elements/capsfilter) use
1002 * pipelines with a dangling sinkpad but no sink element.
1003 * These tests assume that no EOS message is ever
1004 * posted on the bus so let's keep that behaviour.
1005 * In valid pipelines this doesn't make a difference.
1007 return result && n_eos > 0;
1011 /* Check if the bin is STREAM_START. We do this by scanning all sinks and
1012 * checking if they posted an STREAM_START message.
1014 * call with bin LOCK */
1016 is_stream_start (GstBin * bin, guint32 * seqnum, gboolean * have_group_id,
1022 gboolean first = TRUE, same_group_id = TRUE;
1024 *have_group_id = TRUE;
1027 for (walk = bin->children; walk; walk = g_list_next (walk)) {
1028 GstElement *element;
1030 element = GST_ELEMENT_CAST (walk->data);
1031 if (bin_element_is_sink (element, bin) == 0) {
1032 /* check if element posted STREAM_START */
1034 find_message (bin, GST_OBJECT_CAST (element),
1035 GST_MESSAGE_STREAM_START))) {
1036 GST_DEBUG ("sink '%s' posted STREAM_START", GST_ELEMENT_NAME (element));
1037 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1038 if (gst_message_parse_group_id (GST_MESSAGE_CAST (msgs->data),
1042 *group_id = tmp_group_id;
1044 if (tmp_group_id != *group_id)
1045 same_group_id = FALSE;
1048 *have_group_id = FALSE;
1051 GST_DEBUG ("sink '%s' did not post STREAM_START yet",
1052 GST_ELEMENT_NAME (element));
1059 /* If all have a group_id we only consider this stream started
1060 * if all group ids were the same and all sinks posted a stream-start
1063 return same_group_id && result;
1064 /* otherwise consider this stream started after all sinks
1065 * have reported stream-start for backward compatibility.
1066 * FIXME 2.0: This should go away! */
1071 unlink_pads (const GValue * item, gpointer user_data)
1076 pad = g_value_get_object (item);
1078 if ((peer = gst_pad_get_peer (pad))) {
1079 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
1080 gst_pad_unlink (pad, peer);
1082 gst_pad_unlink (peer, pad);
1083 gst_object_unref (peer);
1087 /* vmethod that adds an element to a bin
1092 gst_bin_add_func (GstBin * bin, GstElement * element)
1096 gboolean is_sink, is_source, provides_clock, requires_clock;
1097 GstMessage *clock_message = NULL, *async_message = NULL;
1098 GstStateChangeReturn ret;
1101 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1103 /* we obviously can't add ourself to ourself */
1104 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1107 /* get the element name to make sure it is unique in this bin. */
1108 GST_OBJECT_LOCK (element);
1109 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1110 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1111 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1113 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1115 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1116 GST_OBJECT_UNLOCK (element);
1118 GST_OBJECT_LOCK (bin);
1120 /* then check to see if the element's name is already taken in the bin,
1121 * we can safely take the lock here. This check is probably bogus because
1122 * you can safely change the element name after this check and before setting
1123 * the object parent. The window is very small though... */
1124 if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
1125 goto duplicate_name;
1127 /* set the element's parent and add the element to the bin's list of children */
1128 if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
1129 GST_OBJECT_CAST (bin))))
1132 /* if we add a sink we become a sink */
1134 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
1136 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SINK);
1139 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was source",
1141 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SOURCE);
1143 if (provides_clock) {
1144 GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
1146 gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
1147 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1149 if (requires_clock) {
1150 GST_DEBUG_OBJECT (bin, "element \"%s\" requires a clock", elem_name);
1151 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1154 bin->children = g_list_prepend (bin->children, element);
1156 bin->children_cookie++;
1157 if (!GST_BIN_IS_NO_RESYNC (bin))
1158 bin->priv->structure_cookie++;
1160 /* distribute the bus */
1161 gst_element_set_bus (element, bin->child_bus);
1163 /* propagate the current base_time, start_time and clock */
1164 gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
1165 gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
1166 /* it's possible that the element did not accept the clock but
1167 * that is not important right now. When the pipeline goes to PLAYING,
1168 * a new clock will be selected */
1169 gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
1171 for (l = bin->priv->contexts; l; l = l->next)
1172 gst_element_set_context (element, l->data);
1175 /* set the cached index on the children */
1176 if (bin->priv->index)
1177 gst_element_set_index (element, bin->priv->index);
1180 ret = GST_STATE_RETURN (bin);
1181 /* no need to update the state if we are in error */
1182 if (ret == GST_STATE_CHANGE_FAILURE)
1183 goto no_state_recalc;
1185 /* update the bin state, the new element could have been an ASYNC or
1186 * NO_PREROLL element */
1187 ret = GST_STATE_RETURN (element);
1188 GST_DEBUG_OBJECT (bin, "added %s element",
1189 gst_element_state_change_return_get_name (ret));
1192 case GST_STATE_CHANGE_ASYNC:
1194 /* create message to track this aync element when it posts an async-done
1196 async_message = gst_message_new_async_start (GST_OBJECT_CAST (element));
1199 case GST_STATE_CHANGE_NO_PREROLL:
1200 /* ignore all async elements we might have and commit our state */
1201 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1203 case GST_STATE_CHANGE_FAILURE:
1210 GST_OBJECT_UNLOCK (bin);
1212 /* post the messages on the bus of the element so that the bin can handle
1215 gst_element_post_message (element, clock_message);
1218 gst_element_post_message (element, async_message);
1220 /* unlink all linked pads */
1221 it = gst_element_iterate_pads (element);
1222 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1223 gst_iterator_free (it);
1225 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
1228 g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
1229 gst_child_proxy_child_added ((GstChildProxy *) bin, (GObject *) element,
1236 /* ERROR handling here */
1239 GST_OBJECT_LOCK (bin);
1240 g_warning ("Cannot add bin '%s' to itself", GST_ELEMENT_NAME (bin));
1241 GST_OBJECT_UNLOCK (bin);
1246 g_warning ("Name '%s' is not unique in bin '%s', not adding",
1247 elem_name, GST_ELEMENT_NAME (bin));
1248 GST_OBJECT_UNLOCK (bin);
1254 g_warning ("Element '%s' already has parent", elem_name);
1255 GST_OBJECT_UNLOCK (bin);
1264 * @element: (transfer full): the #GstElement to add
1266 * Adds the given element to the bin. Sets the element's parent, and thus
1267 * takes ownership of the element. An element can only be added to one bin.
1269 * If the element's pads are linked to other pads, the pads will be unlinked
1270 * before the element is added to the bin.
1273 * When you add an element to an already-running pipeline, you will have to
1274 * take care to set the state of the newly-added element to the desired
1275 * state (usually PLAYING or PAUSED, same you set the pipeline to originally)
1276 * with gst_element_set_state(), or use gst_element_sync_state_with_parent().
1277 * The bin or pipeline will not take care of this for you.
1282 * Returns: %TRUE if the element could be added, %FALSE if
1283 * the bin does not want to accept the element.
1286 gst_bin_add (GstBin * bin, GstElement * element)
1288 GstBinClass *bclass;
1291 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1292 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1294 bclass = GST_BIN_GET_CLASS (bin);
1296 if (G_UNLIKELY (bclass->add_element == NULL))
1299 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1300 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1301 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1303 result = bclass->add_element (bin, element);
1307 /* ERROR handling */
1310 g_warning ("adding elements to bin '%s' is not supported",
1311 GST_ELEMENT_NAME (bin));
1316 /* remove an element from the bin
1321 gst_bin_remove_func (GstBin * bin, GstElement * element)
1325 gboolean is_sink, is_source, provides_clock, requires_clock;
1326 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1327 GstMessage *clock_message = NULL;
1328 GstClock **provided_clock_p;
1329 GstElement **clock_provider_p;
1331 gboolean other_async, this_async, have_no_preroll;
1332 GstStateChangeReturn ret;
1334 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1336 GST_OBJECT_LOCK (bin);
1338 GST_OBJECT_LOCK (element);
1339 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1341 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1344 /* remove the parent ref */
1345 GST_OBJECT_PARENT (element) = NULL;
1347 /* grab element name so we can print it */
1348 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1349 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1351 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1353 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1354 GST_OBJECT_UNLOCK (element);
1358 othersource = FALSE;
1359 otherprovider = FALSE;
1360 otherrequirer = FALSE;
1361 have_no_preroll = FALSE;
1362 /* iterate the elements, we collect which ones are async and no_preroll. We
1363 * also remove the element when we find it. */
1364 for (walk = bin->children; walk; walk = next) {
1365 GstElement *child = GST_ELEMENT_CAST (walk->data);
1367 next = g_list_next (walk);
1369 if (child == element) {
1371 /* remove the element */
1372 bin->children = g_list_delete_link (bin->children, walk);
1374 gboolean child_sink, child_source, child_provider, child_requirer;
1376 GST_OBJECT_LOCK (child);
1377 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1378 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1380 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1382 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1383 /* when we remove a sink, check if there are other sinks. */
1384 if (is_sink && !othersink && child_sink)
1386 if (is_source && !othersource && child_source)
1388 if (provides_clock && !otherprovider && child_provider)
1389 otherprovider = TRUE;
1390 if (requires_clock && !otherrequirer && child_requirer)
1391 otherrequirer = TRUE;
1392 /* check if we have NO_PREROLL children */
1393 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1394 have_no_preroll = TRUE;
1395 GST_OBJECT_UNLOCK (child);
1399 /* the element must have been in the bin's list of children */
1400 if (G_UNLIKELY (!found))
1403 /* we now removed the element from the list of elements, increment the cookie
1404 * so that others can detect a change in the children list. */
1406 bin->children_cookie++;
1407 if (!GST_BIN_IS_NO_RESYNC (bin))
1408 bin->priv->structure_cookie++;
1410 if (is_sink && !othersink) {
1411 /* we're not a sink anymore */
1412 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1413 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1415 if (is_source && !othersource) {
1416 /* we're not a source anymore */
1417 GST_DEBUG_OBJECT (bin, "we removed the last source");
1418 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1420 if (provides_clock && !otherprovider) {
1421 /* we're not a clock provider anymore */
1422 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1423 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1425 if (requires_clock && !otherrequirer) {
1426 /* we're not a clock requirer anymore */
1427 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1428 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1431 /* if the clock provider for this element is removed, we lost
1432 * the clock as well, we need to inform the parent of this
1433 * so that it can select a new clock */
1434 if (bin->clock_provider == element) {
1435 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1436 bin->clock_dirty = TRUE;
1438 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1439 provided_clock_p = &bin->provided_clock;
1440 clock_provider_p = &bin->clock_provider;
1441 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1442 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1445 /* remove messages for the element, if there was a pending ASYNC_START
1446 * message we must see if removing the element caused the bin to lose its
1449 other_async = FALSE;
1450 for (walk = bin->messages; walk; walk = next) {
1451 GstMessage *message = (GstMessage *) walk->data;
1452 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1455 next = g_list_next (walk);
1458 switch (GST_MESSAGE_TYPE (message)) {
1459 case GST_MESSAGE_ASYNC_START:
1465 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1467 case GST_MESSAGE_STRUCTURE_CHANGE:
1471 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1473 /* it's unlikely that this message is still in the list of messages
1474 * because this would mean that a link/unlink is busy in another thread
1475 * while we remove the element. We still have to remove the message
1476 * because we might not receive the done message anymore when the element
1477 * is removed from the bin. */
1478 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1479 if (owner == element)
1490 /* delete all message types */
1491 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1492 message, elem_name);
1493 bin->messages = g_list_delete_link (bin->messages, walk);
1494 gst_message_unref (message);
1498 /* get last return */
1499 ret = GST_STATE_RETURN (bin);
1501 /* no need to update the state if we are in error */
1502 if (ret == GST_STATE_CHANGE_FAILURE)
1503 goto no_state_recalc;
1505 if (!other_async && this_async) {
1506 /* all other elements were not async and we removed the async one,
1507 * handle the async-done case because we are not async anymore now. */
1508 GST_DEBUG_OBJECT (bin,
1509 "we removed the last async element, have no_preroll %d",
1512 /* the current state return of the bin depends on if there are no_preroll
1513 * elements in the pipeline or not */
1514 if (have_no_preroll)
1515 ret = GST_STATE_CHANGE_NO_PREROLL;
1517 ret = GST_STATE_CHANGE_SUCCESS;
1519 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1521 GST_DEBUG_OBJECT (bin,
1522 "recalc state preroll: %d, other async: %d, this async %d",
1523 have_no_preroll, other_async, this_async);
1525 if (have_no_preroll) {
1526 ret = GST_STATE_CHANGE_NO_PREROLL;
1527 } else if (other_async) {
1528 /* there are other async elements and we were not doing an async state
1529 * change, change our pending state and go async */
1530 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1531 GST_STATE_NEXT (bin) = GST_STATE (bin);
1532 GST_STATE_PENDING (bin) = GST_STATE (bin);
1534 ret = GST_STATE_CHANGE_ASYNC;
1536 GST_STATE_RETURN (bin) = ret;
1540 gst_element_set_bus (element, NULL);
1541 /* Clear the clock we provided to the element */
1542 gst_element_set_clock (element, NULL);
1543 GST_OBJECT_UNLOCK (bin);
1546 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1548 /* unlink all linked pads */
1549 it = gst_element_iterate_pads (element);
1550 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1551 gst_iterator_free (it);
1553 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1556 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1557 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1561 /* element is really out of our control now */
1562 gst_object_unref (element);
1566 /* ERROR handling */
1569 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1570 GST_ELEMENT_NAME (bin));
1571 GST_OBJECT_UNLOCK (element);
1572 GST_OBJECT_UNLOCK (bin);
1581 * @element: (transfer none): the #GstElement to remove
1583 * Removes the element from the bin, unparenting it as well.
1584 * Unparenting the element means that the element will be dereferenced,
1585 * so if the bin holds the only reference to the element, the element
1586 * will be freed in the process of removing it from the bin. If you
1587 * want the element to still exist after removing, you need to call
1588 * gst_object_ref() before removing it from the bin.
1590 * If the element's pads are linked to other pads, the pads will be unlinked
1591 * before the element is removed from the bin.
1595 * Returns: %TRUE if the element could be removed, %FALSE if
1596 * the bin does not want to remove the element.
1599 gst_bin_remove (GstBin * bin, GstElement * element)
1601 GstBinClass *bclass;
1604 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1605 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1607 bclass = GST_BIN_GET_CLASS (bin);
1609 if (G_UNLIKELY (bclass->remove_element == NULL))
1612 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1613 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1615 result = bclass->remove_element (bin, element);
1619 /* ERROR handling */
1622 g_warning ("removing elements from bin '%s' is not supported",
1623 GST_ELEMENT_NAME (bin));
1629 * gst_bin_iterate_elements:
1632 * Gets an iterator for the elements in this bin.
1634 * MT safe. Caller owns returned value.
1636 * Returns: (transfer full): a #GstIterator of #GstElement, or %NULL
1639 gst_bin_iterate_elements (GstBin * bin)
1641 GstIterator *result;
1643 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1645 GST_OBJECT_LOCK (bin);
1646 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1647 GST_OBJECT_GET_LOCK (bin),
1648 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1649 GST_OBJECT_UNLOCK (bin);
1654 static GstIteratorItem
1655 iterate_child_recurse (GstIterator * it, const GValue * item)
1657 GstElement *child = g_value_get_object (item);
1659 if (GST_IS_BIN (child)) {
1660 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1662 gst_iterator_push (it, other);
1664 return GST_ITERATOR_ITEM_PASS;
1668 * gst_bin_iterate_recurse:
1671 * Gets an iterator for the elements in this bin.
1672 * This iterator recurses into GstBin children.
1674 * MT safe. Caller owns returned value.
1676 * Returns: (transfer full): a #GstIterator of #GstElement, or %NULL
1679 gst_bin_iterate_recurse (GstBin * bin)
1681 GstIterator *result;
1683 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1685 GST_OBJECT_LOCK (bin);
1686 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1687 GST_OBJECT_GET_LOCK (bin),
1688 &bin->children_cookie,
1690 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1691 GST_OBJECT_UNLOCK (bin);
1696 /* returns 0 when TRUE because this is a GCompareFunc */
1699 bin_element_is_sink (GstElement * child, GstBin * bin)
1703 /* we lock the child here for the remainder of the function to
1704 * get its name and flag safely. */
1705 GST_OBJECT_LOCK (child);
1706 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1708 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1709 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1711 GST_OBJECT_UNLOCK (child);
1712 return is_sink ? 0 : 1;
1716 sink_iterator_filter (const GValue * vchild, GValue * vbin)
1718 GstBin *bin = g_value_get_object (vbin);
1719 GstElement *child = g_value_get_object (vchild);
1721 return (bin_element_is_sink (child, bin));
1725 * gst_bin_iterate_sinks:
1728 * Gets an iterator for all elements in the bin that have the
1729 * #GST_ELEMENT_FLAG_SINK flag set.
1731 * MT safe. Caller owns returned value.
1733 * Returns: (transfer full): a #GstIterator of #GstElement, or %NULL
1736 gst_bin_iterate_sinks (GstBin * bin)
1738 GstIterator *children;
1739 GstIterator *result;
1740 GValue vbin = { 0, };
1742 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1744 g_value_init (&vbin, GST_TYPE_BIN);
1745 g_value_set_object (&vbin, bin);
1747 children = gst_bin_iterate_elements (bin);
1748 result = gst_iterator_filter (children,
1749 (GCompareFunc) sink_iterator_filter, &vbin);
1751 g_value_unset (&vbin);
1756 /* returns 0 when TRUE because this is a GCompareFunc */
1759 bin_element_is_src (GstElement * child, GstBin * bin)
1763 /* we lock the child here for the remainder of the function to
1764 * get its name and other info safely. */
1765 GST_OBJECT_LOCK (child);
1766 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1768 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1769 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
1771 GST_OBJECT_UNLOCK (child);
1772 return is_src ? 0 : 1;
1776 src_iterator_filter (const GValue * vchild, GValue * vbin)
1778 GstBin *bin = g_value_get_object (vbin);
1779 GstElement *child = g_value_get_object (vchild);
1781 return (bin_element_is_src (child, bin));
1785 * gst_bin_iterate_sources:
1788 * Gets an iterator for all elements in the bin that have the
1789 * #GST_ELEMENT_FLAG_SOURCE flag set.
1791 * MT safe. Caller owns returned value.
1793 * Returns: (transfer full): a #GstIterator of #GstElement, or %NULL
1796 gst_bin_iterate_sources (GstBin * bin)
1798 GstIterator *children;
1799 GstIterator *result;
1800 GValue vbin = { 0, };
1802 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1804 g_value_init (&vbin, GST_TYPE_BIN);
1805 g_value_set_object (&vbin, bin);
1807 children = gst_bin_iterate_elements (bin);
1808 result = gst_iterator_filter (children,
1809 (GCompareFunc) src_iterator_filter, &vbin);
1811 g_value_unset (&vbin);
1819 static GstStateChangeReturn
1820 gst_bin_get_state_func (GstElement * element, GstState * state,
1821 GstState * pending, GstClockTime timeout)
1823 GstStateChangeReturn ret;
1825 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
1828 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
1834 /***********************************************
1835 * Topologically sorted iterator
1836 * see http://en.wikipedia.org/wiki/Topological_sorting
1838 * For each element in the graph, an entry is kept in a HashTable
1839 * with its number of srcpad connections (degree).
1840 * We then change state of all elements without dependencies
1841 * (degree 0) and decrement the degree of all elements connected
1842 * on the sinkpads. When an element reaches degree 0, its state is
1844 * When all elements are handled the algorithm stops.
1846 typedef struct _GstBinSortIterator
1849 GQueue queue; /* elements queued for state change */
1850 GstBin *bin; /* bin we iterate */
1851 gint mode; /* adding or removing dependency */
1852 GstElement *best; /* next element with least dependencies */
1853 gint best_deg; /* best degree */
1854 GHashTable *hash; /* hashtable with element dependencies */
1855 gboolean dirty; /* we detected structure change */
1856 } GstBinSortIterator;
1859 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
1860 GstBinSortIterator * copy)
1862 GHashTableIter iter;
1863 gpointer key, value;
1865 copy->queue = it->queue;
1866 g_queue_foreach (©->queue, (GFunc) gst_object_ref, NULL);
1868 copy->bin = gst_object_ref (it->bin);
1870 copy->best = gst_object_ref (it->best);
1872 copy->hash = g_hash_table_new (NULL, NULL);
1873 g_hash_table_iter_init (&iter, it->hash);
1874 while (g_hash_table_iter_next (&iter, &key, &value))
1875 g_hash_table_insert (copy->hash, key, value);
1878 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
1879 #define HASH_SET_DEGREE(bit, elem, deg) \
1880 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
1881 #define HASH_GET_DEGREE(bit, elem) \
1882 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
1884 /* add element to queue of next elements in the iterator.
1885 * We push at the tail to give higher priority elements a
1888 add_to_queue (GstBinSortIterator * bit, GstElement * element)
1890 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
1891 GST_ELEMENT_NAME (element));
1892 gst_object_ref (element);
1893 g_queue_push_tail (&bit->queue, element);
1894 HASH_SET_DEGREE (bit, element, -1);
1898 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
1902 if ((find = g_queue_find (&bit->queue, element))) {
1903 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
1904 GST_ELEMENT_NAME (element));
1906 g_queue_delete_link (&bit->queue, find);
1907 gst_object_unref (element);
1909 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
1910 GST_ELEMENT_NAME (element));
1914 /* clear the queue, unref all objects as we took a ref when
1915 * we added them to the queue */
1917 clear_queue (GQueue * queue)
1921 while ((p = g_queue_pop_head (queue)))
1922 gst_object_unref (p);
1925 /* set all degrees to 0. Elements marked as a sink are
1926 * added to the queue immediately. Since we only look at the SINK flag of the
1927 * element, it is possible that we add non-sinks to the queue. These will be
1928 * removed from the queue again when we can prove that it provides data for some
1931 reset_degree (GstElement * element, GstBinSortIterator * bit)
1935 /* sinks are added right away */
1936 GST_OBJECT_LOCK (element);
1937 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1938 GST_OBJECT_UNLOCK (element);
1941 add_to_queue (bit, element);
1943 /* others are marked with 0 and handled when sinks are done */
1944 HASH_SET_DEGREE (bit, element, 0);
1948 /* adjust the degree of all elements connected to the given
1949 * element. If a degree of an element drops to 0, it is
1950 * added to the queue of elements to schedule next.
1952 * We have to make sure not to cross the bin boundary this element
1956 update_degree (GstElement * element, GstBinSortIterator * bit)
1958 gboolean linked = FALSE;
1960 GST_OBJECT_LOCK (element);
1961 /* don't touch degree if element has no sinkpads */
1962 if (element->numsinkpads != 0) {
1963 /* loop over all sinkpads, decrement degree for all connected
1964 * elements in this bin */
1967 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
1970 pad = GST_PAD_CAST (pads->data);
1972 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
1973 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
1974 GST_MESSAGE_STRUCTURE_CHANGE))) {
1975 /* mark the iterator as dirty because we won't be updating the degree
1976 * of the peer parent now. This would result in the 'loop detected'
1977 * later on because the peer parent element could become the best next
1978 * element with a degree > 0. We will simply continue our state
1979 * changes and we'll eventually resync when the unlink completed and
1980 * the iterator cookie is updated. */
1985 if ((peer = gst_pad_get_peer (pad))) {
1986 GstElement *peer_element;
1988 if ((peer_element = gst_pad_get_parent_element (peer))) {
1989 GST_OBJECT_LOCK (peer_element);
1990 /* check that we don't go outside of this bin */
1991 if (GST_OBJECT_CAST (peer_element)->parent ==
1992 GST_OBJECT_CAST (bit->bin)) {
1993 gint old_deg, new_deg;
1995 old_deg = HASH_GET_DEGREE (bit, peer_element);
1997 /* check to see if we added an element as sink that was not really a
1998 * sink because it was connected to some other element. */
1999 if (old_deg == -1) {
2000 remove_from_queue (bit, peer_element);
2003 new_deg = old_deg + bit->mode;
2005 GST_DEBUG_OBJECT (bit->bin,
2006 "change element %s, degree %d->%d, linked to %s",
2007 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
2008 GST_ELEMENT_NAME (element));
2010 /* update degree, it is possible that an element was in 0 and
2011 * reaches -1 here. This would mean that the element had no sinkpads
2012 * but became linked while the state change was happening. We will
2013 * resync on this with the structure change message. */
2015 /* degree hit 0, add to queue */
2016 add_to_queue (bit, peer_element);
2018 HASH_SET_DEGREE (bit, peer_element, new_deg);
2022 GST_OBJECT_UNLOCK (peer_element);
2023 gst_object_unref (peer_element);
2025 gst_object_unref (peer);
2030 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2031 GST_ELEMENT_NAME (element));
2033 GST_OBJECT_UNLOCK (element);
2036 /* find the next best element not handled yet. This is the one
2037 * with the lowest non-negative degree */
2039 find_element (GstElement * element, GstBinSortIterator * bit)
2043 /* element is already handled */
2044 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2047 /* first element or element with smaller degree */
2048 if (bit->best == NULL || bit->best_deg > degree) {
2049 bit->best = element;
2050 bit->best_deg = degree;
2054 /* get next element in iterator. */
2055 static GstIteratorResult
2056 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2059 GstBin *bin = bit->bin;
2061 /* empty queue, we have to find a next best element */
2062 if (g_queue_is_empty (&bit->queue)) {
2064 bit->best_deg = G_MAXINT;
2065 g_list_foreach (bin->children, (GFunc) find_element, bit);
2066 if ((best = bit->best)) {
2067 /* when we detected an unlink, don't warn because our degrees might be
2068 * screwed up. We will resync later */
2069 if (bit->best_deg != 0 && !bit->dirty) {
2070 /* we don't fail on this one yet */
2071 GST_WARNING_OBJECT (bin, "loop dected in graph");
2072 g_warning ("loop detected in the graph of bin '%s'!!",
2073 GST_ELEMENT_NAME (bin));
2075 /* best unhandled element, schedule as next element */
2076 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2077 GST_ELEMENT_NAME (best));
2078 HASH_SET_DEGREE (bit, best, -1);
2079 g_value_set_object (result, best);
2081 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2082 /* no more unhandled elements, we are done */
2083 return GST_ITERATOR_DONE;
2086 /* everything added to the queue got reffed */
2087 best = g_queue_pop_head (&bit->queue);
2088 g_value_set_object (result, best);
2089 gst_object_unref (best);
2092 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2093 /* update degrees of linked elements */
2094 update_degree (best, bit);
2096 return GST_ITERATOR_OK;
2099 /* clear queues, recalculate the degrees and restart. */
2101 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2103 GstBin *bin = bit->bin;
2105 GST_DEBUG_OBJECT (bin, "resync");
2107 clear_queue (&bit->queue);
2109 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2110 /* calc degrees, incrementing */
2112 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2113 /* for the rest of the function we decrement the degrees */
2117 /* clear queues, unref bin and free iterator. */
2119 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2121 GstBin *bin = bit->bin;
2123 GST_DEBUG_OBJECT (bin, "free");
2124 clear_queue (&bit->queue);
2125 g_hash_table_destroy (bit->hash);
2126 gst_object_unref (bin);
2129 /* should be called with the bin LOCK held */
2130 static GstIterator *
2131 gst_bin_sort_iterator_new (GstBin * bin)
2133 GstBinSortIterator *result;
2135 /* we don't need an ItemFunction because we ref the items in the _next
2137 result = (GstBinSortIterator *)
2138 gst_iterator_new (sizeof (GstBinSortIterator),
2140 GST_OBJECT_GET_LOCK (bin),
2141 &bin->priv->structure_cookie,
2142 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2143 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2144 (GstIteratorItemFunction) NULL,
2145 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2146 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2147 g_queue_init (&result->queue);
2148 result->hash = g_hash_table_new (NULL, NULL);
2149 gst_object_ref (bin);
2151 gst_bin_sort_iterator_resync (result);
2153 return (GstIterator *) result;
2157 * gst_bin_iterate_sorted:
2160 * Gets an iterator for the elements in this bin in topologically
2161 * sorted order. This means that the elements are returned from
2162 * the most downstream elements (sinks) to the sources.
2164 * This function is used internally to perform the state changes
2165 * of the bin elements and for clock selection.
2167 * MT safe. Caller owns returned value.
2169 * Returns: (transfer full): a #GstIterator of #GstElement, or %NULL
2172 gst_bin_iterate_sorted (GstBin * bin)
2174 GstIterator *result;
2176 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2178 GST_OBJECT_LOCK (bin);
2179 result = gst_bin_sort_iterator_new (bin);
2180 GST_OBJECT_UNLOCK (bin);
2185 static GstStateChangeReturn
2186 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2187 GstClockTime base_time, GstClockTime start_time, GstState current,
2190 GstStateChangeReturn ret;
2191 GstState child_current, child_pending;
2195 GST_STATE_LOCK (element);
2197 GST_OBJECT_LOCK (element);
2198 /* set base_time and start time on child */
2199 GST_ELEMENT_START_TIME (element) = start_time;
2200 element->base_time = base_time;
2201 /* peel off the locked flag */
2202 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2203 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2204 ret = GST_STATE_RETURN (element);
2205 child_current = GST_STATE (element);
2206 child_pending = GST_STATE_PENDING (element);
2207 GST_OBJECT_UNLOCK (element);
2209 /* skip locked elements */
2210 if (G_UNLIKELY (locked))
2213 /* if the element was no preroll, just start changing the state regardless
2214 * if it had async elements (in the case of a bin) because they won't preroll
2216 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2217 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2221 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2222 "current %s pending %s, desired next %s",
2223 gst_element_state_get_name (child_current),
2224 gst_element_state_get_name (child_pending),
2225 gst_element_state_get_name (next));
2227 /* always recurse into bins so that we can set the base time */
2228 if (GST_IS_BIN (element))
2231 /* Try not to change the state of elements that are already in the state we're
2233 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2234 /* child is already at the requested state, return previous return. Note that
2235 * if the child has a pending state to next, we will still call the
2236 * set_state function */
2238 } else if (next > current) {
2239 /* upward state change */
2240 if (child_pending == GST_STATE_VOID_PENDING) {
2241 /* .. and the child is not busy doing anything */
2242 if (child_current > next) {
2243 /* .. and is already past the requested state, assume it got there
2245 ret = GST_STATE_CHANGE_SUCCESS;
2248 } else if (child_pending > child_current) {
2249 /* .. and the child is busy going upwards */
2250 if (child_current >= next) {
2251 /* .. and is already past the requested state, assume it got there
2253 ret = GST_STATE_CHANGE_SUCCESS;
2257 /* .. and the child is busy going downwards */
2258 if (child_current > next) {
2259 /* .. and is already past the requested state, assume it got there
2261 ret = GST_STATE_CHANGE_SUCCESS;
2265 } else if (next < current) {
2266 /* downward state change */
2267 if (child_pending == GST_STATE_VOID_PENDING) {
2268 /* .. and the child is not busy doing anything */
2269 if (child_current < next) {
2270 /* .. and is already past the requested state, assume it got there
2272 ret = GST_STATE_CHANGE_SUCCESS;
2275 } else if (child_pending < child_current) {
2276 /* .. and the child is busy going downwards */
2277 if (child_current <= next) {
2278 /* .. and is already past the requested state, assume it got there
2280 ret = GST_STATE_CHANGE_SUCCESS;
2284 /* .. and the child is busy going upwards */
2285 if (child_current < next) {
2286 /* .. and is already past the requested state, assume it got there
2288 ret = GST_STATE_CHANGE_SUCCESS;
2295 GST_OBJECT_LOCK (bin);
2296 /* the element was busy with an upwards async state change, we must wait for
2297 * an ASYNC_DONE message before we attemp to change the state. */
2299 find_message (bin, GST_OBJECT_CAST (element),
2300 GST_MESSAGE_ASYNC_START))) {
2301 #ifndef GST_DISABLE_GST_DEBUG
2302 GstMessage *message = GST_MESSAGE_CAST (found->data);
2304 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2305 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2307 /* only wait for upward state changes */
2308 if (next > current) {
2309 /* We found an async element check if we can force its state to change or
2310 * if we have to wait for it to preroll. */
2314 GST_OBJECT_UNLOCK (bin);
2317 GST_DEBUG_OBJECT (bin,
2318 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2319 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2320 GST_TIME_ARGS (base_time));
2323 ret = gst_element_set_state (element, next);
2325 GST_STATE_UNLOCK (element);
2331 GST_DEBUG_OBJECT (element,
2332 "element is locked, return previous return %s",
2333 gst_element_state_change_return_get_name (ret));
2334 GST_STATE_UNLOCK (element);
2339 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2340 "skipping transition from %s to %s",
2341 gst_element_state_get_name (child_current),
2342 gst_element_state_get_name (next));
2343 GST_STATE_UNLOCK (element);
2348 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2349 GST_OBJECT_UNLOCK (bin);
2350 GST_STATE_UNLOCK (element);
2351 return GST_STATE_CHANGE_ASYNC;
2355 /* gst_iterator_fold functions for pads_activate
2356 * Stop the iterator if activating one pad failed. */
2358 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2360 GstPad *pad = g_value_get_object (vpad);
2361 gboolean cont = TRUE;
2363 if (!(cont = gst_pad_set_active (pad, *active)))
2364 g_value_set_boolean (ret, FALSE);
2369 /* returns false on error or early cutout of the fold, true if all
2370 * pads in @iter were (de)activated successfully. */
2372 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2374 GstIteratorResult ires;
2377 /* no need to unset this later, it's just a boolean */
2378 g_value_init (&ret, G_TYPE_BOOLEAN);
2379 g_value_set_boolean (&ret, TRUE);
2382 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2385 case GST_ITERATOR_RESYNC:
2386 /* need to reset the result again */
2387 g_value_set_boolean (&ret, TRUE);
2388 gst_iterator_resync (iter);
2390 case GST_ITERATOR_DONE:
2391 /* all pads iterated, return collected value */
2394 /* iterator returned _ERROR or premature end with _OK,
2395 * mark an error and exit */
2396 g_value_set_boolean (&ret, FALSE);
2401 /* return collected value */
2402 return g_value_get_boolean (&ret);
2405 /* is called with STATE_LOCK
2408 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2413 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2415 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2416 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2417 gst_iterator_free (iter);
2418 if (G_UNLIKELY (!fold_ok))
2421 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2428 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2434 * gst_bin_recalculate_latency:
2437 * Query @bin for the current latency using and reconfigures this latency to all the
2438 * elements with a LATENCY event.
2440 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2441 * is posted on the bus.
2443 * This function simply emits the 'do-latency' signal so any custom latency
2444 * calculations will be performed.
2446 * Returns: %TRUE if the latency could be queried and reconfigured.
2449 gst_bin_recalculate_latency (GstBin * bin)
2453 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2454 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2460 gst_bin_do_latency_func (GstBin * bin)
2463 GstElement *element;
2464 GstClockTime min_latency, max_latency;
2467 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2469 element = GST_ELEMENT_CAST (bin);
2471 GST_DEBUG_OBJECT (element, "querying latency");
2473 query = gst_query_new_latency ();
2474 if ((res = gst_element_query (element, query))) {
2477 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2479 GST_DEBUG_OBJECT (element,
2480 "got min latency %" GST_TIME_FORMAT ", max latency %"
2481 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2482 GST_TIME_ARGS (max_latency), live);
2484 if (max_latency < min_latency) {
2485 /* this is an impossible situation, some parts of the pipeline might not
2486 * work correctly. We post a warning for now. */
2487 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2488 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2489 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2490 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2493 /* configure latency on elements */
2494 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2496 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2497 GST_TIME_ARGS (min_latency));
2499 GST_WARNING_OBJECT (element,
2500 "did not really configure latency of %" GST_TIME_FORMAT,
2501 GST_TIME_ARGS (min_latency));
2504 /* this is not a real problem, we just don't configure any latency. */
2505 GST_WARNING_OBJECT (element, "failed to query latency");
2507 gst_query_unref (query);
2513 gst_bin_post_message (GstElement * element, GstMessage * msg)
2515 GstElementClass *pklass = (GstElementClass *) parent_class;
2518 ret = pklass->post_message (element, gst_message_ref (msg));
2520 if (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_STATE_CHANGED &&
2521 GST_MESSAGE_SRC (msg) == GST_OBJECT_CAST (element)) {
2522 GstState newstate, pending;
2524 gst_message_parse_state_changed (msg, NULL, &newstate, &pending);
2525 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING) {
2526 GST_BIN_CAST (element)->priv->posted_playing = TRUE;
2527 bin_do_eos (GST_BIN_CAST (element));
2529 GST_BIN_CAST (element)->priv->posted_playing = FALSE;
2533 gst_message_unref (msg);
2538 static GstStateChangeReturn
2539 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2542 GstStateChangeReturn ret;
2543 GstState current, next;
2544 gboolean have_async;
2545 gboolean have_no_preroll;
2546 GstClockTime base_time, start_time;
2549 GValue data = { 0, };
2551 /* we don't need to take the STATE_LOCK, it is already taken */
2552 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2553 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2555 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2556 "changing state of children from %s to %s",
2557 gst_element_state_get_name (current), gst_element_state_get_name (next));
2559 bin = GST_BIN_CAST (element);
2562 case GST_STATE_PLAYING:
2566 GST_OBJECT_LOCK (bin);
2567 toplevel = BIN_IS_TOPLEVEL (bin);
2568 GST_OBJECT_UNLOCK (bin);
2571 gst_bin_recalculate_latency (bin);
2574 case GST_STATE_PAUSED:
2575 /* Clear EOS list on next PAUSED */
2576 GST_OBJECT_LOCK (bin);
2577 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2578 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2579 bin->priv->posted_eos = FALSE;
2580 if (current == GST_STATE_READY)
2581 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2582 GST_OBJECT_UNLOCK (bin);
2583 if (current == GST_STATE_READY)
2584 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2585 goto activate_failure;
2587 case GST_STATE_READY:
2588 /* Clear message list on next READY */
2589 GST_OBJECT_LOCK (bin);
2590 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2591 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2592 GST_OBJECT_UNLOCK (bin);
2593 /* We might not have reached PAUSED yet due to async errors,
2594 * make sure to always deactivate the pads nonetheless */
2595 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2596 goto activate_failure;
2598 case GST_STATE_NULL:
2599 if (current == GST_STATE_READY) {
2602 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2603 goto activate_failure;
2605 /* Remove all non-persistent contexts */
2606 GST_OBJECT_LOCK (bin);
2607 for (l = bin->priv->contexts; l;) {
2608 GstContext *context = l->data;
2610 if (!gst_context_is_persistent (context)) {
2613 gst_context_unref (context);
2615 bin->priv->contexts = g_list_delete_link (bin->priv->contexts, l);
2621 GST_OBJECT_UNLOCK (bin);
2628 /* this flag is used to make the async state changes return immediately. We
2629 * don't want them to interfere with this state change */
2630 GST_OBJECT_LOCK (bin);
2631 bin->polling = TRUE;
2632 GST_OBJECT_UNLOCK (bin);
2634 /* iterate in state change order */
2635 it = gst_bin_iterate_sorted (bin);
2637 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2638 * Note how we don't reset this value when a resync happens, the reason being
2639 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2640 * even after a resync when the async element is gone */
2644 /* take base_time */
2645 base_time = gst_element_get_base_time (element);
2646 start_time = gst_element_get_start_time (element);
2648 have_no_preroll = FALSE;
2652 switch (gst_iterator_next (it, &data)) {
2653 case GST_ITERATOR_OK:
2657 child = g_value_get_object (&data);
2659 /* set state and base_time now */
2660 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2664 case GST_STATE_CHANGE_SUCCESS:
2665 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2666 "child '%s' changed state to %d(%s) successfully",
2667 GST_ELEMENT_NAME (child), next,
2668 gst_element_state_get_name (next));
2670 case GST_STATE_CHANGE_ASYNC:
2672 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2673 "child '%s' is changing state asynchronously to %s",
2674 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2678 case GST_STATE_CHANGE_FAILURE:{
2681 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2682 "child '%s' failed to go to state %d(%s)",
2683 GST_ELEMENT_NAME (child),
2684 next, gst_element_state_get_name (next));
2686 /* Only fail if the child is still inside
2687 * this bin. It might've been removed already
2688 * because of the error by the bin subclass
2689 * to ignore the error. */
2690 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2691 if (parent == GST_OBJECT_CAST (element)) {
2692 /* element is still in bin, really error now */
2693 gst_object_unref (parent);
2696 /* child removed from bin, let the resync code redo the state
2698 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2699 "child '%s' was removed from the bin",
2700 GST_ELEMENT_NAME (child));
2703 gst_object_unref (parent);
2707 case GST_STATE_CHANGE_NO_PREROLL:
2708 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2709 "child '%s' changed state to %d(%s) successfully without preroll",
2710 GST_ELEMENT_NAME (child), next,
2711 gst_element_state_get_name (next));
2712 have_no_preroll = TRUE;
2715 g_assert_not_reached ();
2718 g_value_reset (&data);
2721 case GST_ITERATOR_RESYNC:
2722 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
2723 gst_iterator_resync (it);
2726 case GST_ITERATOR_DONE:
2727 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
2733 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
2734 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
2737 if (have_no_preroll) {
2738 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2739 "we have NO_PREROLL elements %s -> NO_PREROLL",
2740 gst_element_state_change_return_get_name (ret));
2741 ret = GST_STATE_CHANGE_NO_PREROLL;
2742 } else if (have_async) {
2743 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2744 "we have ASYNC elements %s -> ASYNC",
2745 gst_element_state_change_return_get_name (ret));
2746 ret = GST_STATE_CHANGE_ASYNC;
2750 g_value_unset (&data);
2751 gst_iterator_free (it);
2753 GST_OBJECT_LOCK (bin);
2754 bin->polling = FALSE;
2755 /* it's possible that we did not get ASYNC from the children while the bin is
2756 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
2757 * itself as the source. In that case we still want to check if the state
2758 * change completed. */
2759 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
2760 /* no element returned ASYNC and there are no pending async_done messages,
2761 * we can just complete. */
2762 GST_DEBUG_OBJECT (bin, "no async elements");
2765 /* when we get here an ASYNC element was found */
2766 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
2767 /* we ignore ASYNC state changes when we go to READY or NULL */
2768 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
2769 gst_element_state_get_name (GST_STATE_TARGET (bin)));
2773 GST_DEBUG_OBJECT (bin, "check async elements");
2774 /* check if all elements managed to commit their state already */
2775 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
2776 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
2777 * all the elements commited their state while we were doing the state
2778 * change. We will still return ASYNC for consistency but we commit the
2779 * state already so that a _get_state() will return immediately. */
2780 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
2782 GST_DEBUG_OBJECT (bin, "async elements commited");
2783 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
2784 GST_CLOCK_TIME_NONE);
2788 bin->priv->pending_async_done = FALSE;
2789 GST_OBJECT_UNLOCK (bin);
2791 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2792 "done changing bin's state from %s to %s, now in %s, ret %s",
2793 gst_element_state_get_name (current),
2794 gst_element_state_get_name (next),
2795 gst_element_state_get_name (GST_STATE (element)),
2796 gst_element_state_change_return_get_name (ret));
2803 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
2804 "failure (de)activating src pads");
2805 return GST_STATE_CHANGE_FAILURE;
2810 * This function is a utility event handler for seek events.
2811 * It will send the event to all sinks or sources and appropriate
2812 * ghost pads depending on the event-direction.
2814 * Applications are free to override this behaviour and
2815 * implement their own seek handler, but this will work for
2816 * pretty much all cases in practice.
2819 gst_bin_send_event (GstElement * element, GstEvent * event)
2821 GstBin *bin = GST_BIN_CAST (element);
2823 gboolean res = TRUE;
2824 gboolean done = FALSE;
2825 GValue data = { 0, };
2827 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2828 iter = gst_bin_iterate_sources (bin);
2829 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
2830 GST_EVENT_TYPE_NAME (event));
2832 iter = gst_bin_iterate_sinks (bin);
2833 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
2834 GST_EVENT_TYPE_NAME (event));
2838 switch (gst_iterator_next (iter, &data)) {
2839 case GST_ITERATOR_OK:
2841 GstElement *child = g_value_get_object (&data);
2843 gst_event_ref (event);
2844 res &= gst_element_send_event (child, event);
2846 GST_LOG_OBJECT (child, "After handling %s event: %d",
2847 GST_EVENT_TYPE_NAME (event), res);
2849 g_value_reset (&data);
2852 case GST_ITERATOR_RESYNC:
2853 gst_iterator_resync (iter);
2856 case GST_ITERATOR_DONE:
2859 case GST_ITERATOR_ERROR:
2860 g_assert_not_reached ();
2864 g_value_unset (&data);
2865 gst_iterator_free (iter);
2867 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2868 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
2869 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
2870 GST_EVENT_TYPE_NAME (event));
2872 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
2873 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
2874 GST_EVENT_TYPE_NAME (event));
2879 switch (gst_iterator_next (iter, &data)) {
2880 case GST_ITERATOR_OK:
2882 GstPad *pad = g_value_get_object (&data);
2884 gst_event_ref (event);
2885 res &= gst_pad_send_event (pad, event);
2886 GST_LOG_OBJECT (pad, "After handling %s event: %d",
2887 GST_EVENT_TYPE_NAME (event), res);
2890 case GST_ITERATOR_RESYNC:
2891 gst_iterator_resync (iter);
2894 case GST_ITERATOR_DONE:
2897 case GST_ITERATOR_ERROR:
2898 g_assert_not_reached ();
2903 g_value_unset (&data);
2904 gst_iterator_free (iter);
2905 gst_event_unref (event);
2910 /* this is the function called by the threadpool. When async elements commit
2911 * their state, this function will attempt to bring the bin to the next state.
2914 gst_bin_continue_func (BinContinueData * data)
2917 GstState current, next, pending;
2918 GstStateChange transition;
2921 pending = data->pending;
2923 GST_DEBUG_OBJECT (bin, "waiting for state lock");
2924 GST_STATE_LOCK (bin);
2926 GST_DEBUG_OBJECT (bin, "doing state continue");
2927 GST_OBJECT_LOCK (bin);
2929 /* if a new state change happened after this thread was scheduled, we return
2931 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
2934 current = GST_STATE (bin);
2935 next = GST_STATE_GET_NEXT (current, pending);
2936 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
2938 GST_STATE_NEXT (bin) = next;
2939 GST_STATE_PENDING (bin) = pending;
2941 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
2942 GST_OBJECT_UNLOCK (bin);
2944 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
2945 "continue state change %s to %s, final %s",
2946 gst_element_state_get_name (current),
2947 gst_element_state_get_name (next), gst_element_state_get_name (pending));
2949 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
2951 GST_STATE_UNLOCK (bin);
2952 GST_DEBUG_OBJECT (bin, "state continue done");
2954 gst_object_unref (bin);
2955 g_slice_free (BinContinueData, data);
2960 GST_OBJECT_UNLOCK (bin);
2961 GST_STATE_UNLOCK (bin);
2962 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
2963 gst_object_unref (bin);
2964 g_slice_free (BinContinueData, data);
2969 static GstBusSyncReply
2970 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
2972 GstBinClass *bclass;
2974 bclass = GST_BIN_GET_CLASS (bin);
2975 if (bclass->handle_message)
2976 bclass->handle_message (bin, message);
2978 gst_message_unref (message);
2980 return GST_BUS_DROP;
2984 bin_push_state_continue (BinContinueData * data)
2991 klass = GST_BIN_GET_CLASS (bin);
2993 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
2994 g_thread_pool_push (klass->pool, data, NULL);
2997 /* an element started an async state change, if we were not busy with a state
2998 * change, we perform a lost state.
2999 * This function is called with the OBJECT lock.
3002 bin_handle_async_start (GstBin * bin)
3004 GstState old_state, new_state;
3006 GstMessage *amessage = NULL;
3008 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3011 /* get our toplevel state */
3012 toplevel = BIN_IS_TOPLEVEL (bin);
3014 /* prepare an ASYNC_START message, we always post the start message even if we
3015 * are busy with a state change or when we are NO_PREROLL. */
3017 /* non toplevel bin, prepare async-start for the parent */
3018 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
3020 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
3023 /* async starts are ignored when we are NO_PREROLL */
3024 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
3025 goto was_no_preroll;
3027 old_state = GST_STATE (bin);
3029 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
3030 * PLAYING after optionally redistributing the base_time. */
3031 if (old_state > GST_STATE_PAUSED)
3032 new_state = GST_STATE_PAUSED;
3034 new_state = old_state;
3036 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3037 "lost state of %s, new %s", gst_element_state_get_name (old_state),
3038 gst_element_state_get_name (new_state));
3040 GST_STATE (bin) = new_state;
3041 GST_STATE_NEXT (bin) = new_state;
3042 GST_STATE_PENDING (bin) = new_state;
3043 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3044 GST_OBJECT_UNLOCK (bin);
3047 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
3052 /* post our ASYNC_START. */
3053 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
3054 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3056 GST_OBJECT_LOCK (bin);
3062 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3067 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3068 GST_OBJECT_UNLOCK (bin);
3073 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3074 GST_OBJECT_UNLOCK (bin);
3079 /* this function is called when there are no more async elements in the bin. We
3080 * post a state changed message and an ASYNC_DONE message.
3081 * This function is called with the OBJECT lock.
3084 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3085 gboolean flag_pending, GstClockTime running_time)
3087 GstState current, pending, target;
3088 GstStateChangeReturn old_ret;
3089 GstState old_state, old_next;
3090 gboolean toplevel, state_changed = FALSE;
3091 GstMessage *amessage = NULL;
3092 BinContinueData *cont = NULL;
3094 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3097 pending = GST_STATE_PENDING (bin);
3102 /* check if there is something to commit */
3103 if (pending == GST_STATE_VOID_PENDING)
3104 goto nothing_pending;
3106 old_ret = GST_STATE_RETURN (bin);
3107 GST_STATE_RETURN (bin) = ret;
3109 /* move to the next target state */
3110 target = GST_STATE_TARGET (bin);
3111 pending = GST_STATE_PENDING (bin) = target;
3113 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3115 old_state = GST_STATE (bin);
3116 /* this is the state we should go to next */
3117 old_next = GST_STATE_NEXT (bin);
3119 if (old_next != GST_STATE_PLAYING) {
3120 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3121 "committing state from %s to %s, old pending %s",
3122 gst_element_state_get_name (old_state),
3123 gst_element_state_get_name (old_next),
3124 gst_element_state_get_name (pending));
3126 /* update current state */
3127 current = GST_STATE (bin) = old_next;
3129 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3130 "setting state from %s to %s, pending %s",
3131 gst_element_state_get_name (old_state),
3132 gst_element_state_get_name (old_state),
3133 gst_element_state_get_name (pending));
3134 current = old_state;
3137 /* get our toplevel state */
3138 toplevel = BIN_IS_TOPLEVEL (bin);
3140 /* see if we reached the final state. If we are not toplevel, we also have to
3141 * stop here, the parent will continue our state. */
3142 if ((pending == current) || !toplevel) {
3143 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3144 "completed state change, pending VOID");
3146 /* mark VOID pending */
3147 pending = GST_STATE_VOID_PENDING;
3148 GST_STATE_PENDING (bin) = pending;
3149 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3151 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3152 "continue state change, pending %s",
3153 gst_element_state_get_name (pending));
3155 cont = g_slice_new (BinContinueData);
3157 /* ref to the bin */
3158 cont->bin = gst_object_ref (bin);
3159 /* cookie to detect concurrent state change */
3160 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3161 /* pending target state */
3162 cont->pending = pending;
3164 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3165 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3168 if (old_next != GST_STATE_PLAYING) {
3169 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3170 state_changed = TRUE;
3173 GST_OBJECT_UNLOCK (bin);
3175 if (state_changed) {
3176 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3180 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3181 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3182 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3185 GST_OBJECT_LOCK (bin);
3187 /* toplevel, start continue state */
3188 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3189 bin_push_state_continue (cont);
3191 GST_DEBUG_OBJECT (bin, "state change complete");
3192 GST_STATE_BROADCAST (bin);
3198 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3203 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3204 /* if we were busy with a state change and we are requested to flag a
3205 * pending async done, we do so here */
3207 bin->priv->pending_async_done = TRUE;
3212 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3218 bin_do_eos (GstBin * bin)
3223 GST_OBJECT_LOCK (bin);
3224 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3225 * we forward the EOS message to the parent bin or application
3227 eos = GST_STATE (bin) == GST_STATE_PLAYING
3228 && GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING
3229 && bin->priv->posted_playing && is_eos (bin, &seqnum);
3230 GST_OBJECT_UNLOCK (bin);
3233 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3235 GstMessage *tmessage;
3237 /* Clear out any further messages, and reset posted_eos so we can
3238 detect any new EOS that happens (eg, after a seek). Since all
3239 sinks have now posted an EOS, there will be no further EOS events
3240 seen unless there is a new logical EOS */
3241 GST_OBJECT_LOCK (bin);
3242 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3243 bin->priv->posted_eos = FALSE;
3244 GST_OBJECT_UNLOCK (bin);
3246 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3247 gst_message_set_seqnum (tmessage, seqnum);
3248 GST_DEBUG_OBJECT (bin,
3249 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3250 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3255 bin_do_stream_start (GstBin * bin)
3258 gboolean stream_start;
3259 gboolean have_group_id = FALSE;
3262 GST_OBJECT_LOCK (bin);
3263 /* If all sinks are STREAM_START we forward the STREAM_START message
3264 * to the parent bin or application
3266 stream_start = is_stream_start (bin, &seqnum, &have_group_id, &group_id);
3267 GST_OBJECT_UNLOCK (bin);
3270 GstMessage *tmessage;
3272 GST_OBJECT_LOCK (bin);
3273 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3274 GST_OBJECT_UNLOCK (bin);
3276 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3277 gst_message_set_seqnum (tmessage, seqnum);
3279 gst_message_set_group_id (tmessage, group_id);
3281 GST_DEBUG_OBJECT (bin,
3282 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3284 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3288 /* must be called without the object lock as it posts messages */
3290 bin_do_message_forward (GstBin * bin, GstMessage * message)
3292 if (bin->priv->message_forward) {
3293 GstMessage *forwarded;
3295 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3296 GST_MESSAGE_TYPE_NAME (message));
3298 /* we need to convert these messages to element messages so that our parent
3299 * bin can easily ignore them and so that the application can easily
3300 * distinguish between the internally forwarded and the real messages. */
3301 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3302 gst_structure_new ("GstBinForwarded",
3303 "message", GST_TYPE_MESSAGE, message, NULL));
3305 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3310 gst_bin_update_context (GstBin * bin, GstContext * context)
3313 const gchar *context_type;
3315 GST_OBJECT_LOCK (bin);
3316 context_type = gst_context_get_context_type (context);
3317 for (l = bin->priv->contexts; l; l = l->next) {
3318 GstContext *tmp = l->data;
3319 const gchar *tmp_type = gst_context_get_context_type (tmp);
3321 /* Always store newest context but never replace
3322 * a persistent one by a non-persistent one */
3323 if (strcmp (context_type, tmp_type) == 0 &&
3324 (gst_context_is_persistent (context) ||
3325 !gst_context_is_persistent (tmp))) {
3326 gst_context_replace ((GstContext **) & l->data, context);
3330 /* Not found? Add */
3332 bin->priv->contexts =
3333 g_list_prepend (bin->priv->contexts, gst_context_ref (context));
3334 GST_OBJECT_UNLOCK (bin);
3337 /* handle child messages:
3339 * This method is called synchronously when a child posts a message on
3342 * GST_MESSAGE_EOS: This message is only posted by sinks
3343 * in the PLAYING state. If all sinks posted the EOS message, post
3346 * GST_MESSAGE_STATE_DIRTY: Deprecated
3348 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3349 * element posts segment_start twice, only the last message is kept.
3351 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3352 * with the segment_done message. If there are no more segment_start
3353 * messages, post segment_done message upwards.
3355 * GST_MESSAGE_DURATION_CHANGED: clear any cached durations.
3356 * Whenever someone performs a duration query on the bin, we store the
3357 * result so we can answer it quicker the next time. Any element that
3358 * changes its duration marks our cached values invalid.
3359 * This message is also posted upwards. This is currently disabled
3360 * because too many elements don't post DURATION_CHANGED messages when
3361 * the duration changes.
3363 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3364 * can no longer provide a clock. The default bin behaviour is to
3365 * check if the lost clock was the one provided by the bin. If so and
3366 * we are currently in the PLAYING state, we forward the message to
3368 * This message is also generated when we remove a clock provider from
3369 * a bin. If this message is received by the application, it should
3370 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3371 * and a new base_time distribution.
3373 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3374 * can provide a clock. This mostly happens when we add a new clock
3375 * provider to the bin. The default behaviour of the bin is to mark the
3376 * currently selected clock as dirty, which will perform a clock
3377 * recalculation the next time we are asked to provide a clock.
3378 * This message is never sent to the application but is forwarded to
3381 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3382 * the state of the element and the fact that the element will need a
3383 * new base_time. This message is not forwarded to the application.
3385 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3386 * element when it posted ASYNC_START. If all elements are done, post a
3387 * ASYNC_DONE message to the parent.
3389 * OTHER: post upwards.
3392 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3395 GstMessageType type;
3396 GstMessage *tmessage;
3399 src = GST_MESSAGE_SRC (message);
3400 type = GST_MESSAGE_TYPE (message);
3402 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3403 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3404 GST_MESSAGE_TYPE_NAME (message));
3407 case GST_MESSAGE_ERROR:
3409 GST_OBJECT_LOCK (bin);
3411 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3412 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3413 GST_STATE_BROADCAST (bin);
3414 GST_OBJECT_UNLOCK (bin);
3418 case GST_MESSAGE_EOS:
3421 /* collect all eos messages from the children */
3422 bin_do_message_forward (bin, message);
3423 GST_OBJECT_LOCK (bin);
3424 /* ref message for future use */
3425 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3426 GST_OBJECT_UNLOCK (bin);
3431 case GST_MESSAGE_STREAM_START:
3434 /* collect all stream_start messages from the children */
3435 GST_OBJECT_LOCK (bin);
3436 /* ref message for future use */
3437 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3438 GST_OBJECT_UNLOCK (bin);
3440 bin_do_stream_start (bin);
3443 case GST_MESSAGE_STATE_DIRTY:
3445 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3448 gst_message_unref (message);
3451 case GST_MESSAGE_SEGMENT_START:{
3452 gboolean post = FALSE;
3456 gst_message_parse_segment_start (message, &format, &position);
3457 seqnum = gst_message_get_seqnum (message);
3459 bin_do_message_forward (bin, message);
3461 GST_OBJECT_LOCK (bin);
3462 /* if this is the first segment-start, post to parent but not to the
3464 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3465 (GST_OBJECT_PARENT (bin) != NULL)) {
3468 /* replace any previous segment_start message from this source
3469 * with the new segment start message */
3470 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3471 GST_OBJECT_UNLOCK (bin);
3473 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3475 gst_message_set_seqnum (tmessage, seqnum);
3477 /* post segment start with initial format and position. */
3478 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3480 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3484 case GST_MESSAGE_SEGMENT_DONE:
3486 gboolean post = FALSE;
3490 gst_message_parse_segment_done (message, &format, &position);
3491 seqnum = gst_message_get_seqnum (message);
3493 bin_do_message_forward (bin, message);
3495 GST_OBJECT_LOCK (bin);
3496 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3497 /* if there are no more segment_start messages, everybody posted
3498 * a segment_done and we can post one on the bus. */
3500 /* we don't care who still has a pending segment start */
3501 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3504 /* remove all old segment_done messages */
3505 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3507 GST_OBJECT_UNLOCK (bin);
3509 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3511 gst_message_set_seqnum (tmessage, seqnum);
3513 /* post segment done with latest format and position. */
3514 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3516 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3520 case GST_MESSAGE_DURATION_CHANGED:
3522 /* FIXME: remove all cached durations, next time somebody asks
3523 * for duration, we will recalculate. */
3525 GST_OBJECT_LOCK (bin);
3526 bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION_CHANGED);
3527 GST_OBJECT_UNLOCK (bin);
3531 case GST_MESSAGE_CLOCK_LOST:
3533 GstClock **provided_clock_p;
3534 GstElement **clock_provider_p;
3535 gboolean playing, toplevel, provided, forward;
3538 gst_message_parse_clock_lost (message, &clock);
3540 GST_OBJECT_LOCK (bin);
3541 bin->clock_dirty = TRUE;
3542 /* if we lost the clock that we provided, post to parent but
3543 * only if we are not a top-level bin or PLAYING.
3544 * The reason for this is that applications should be able
3545 * to PAUSE/PLAY if they receive this message without worrying
3546 * about the state of the pipeline. */
3547 provided = (clock == bin->provided_clock);
3548 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3549 toplevel = GST_OBJECT_PARENT (bin) == NULL;
3550 forward = provided && (playing || !toplevel);
3552 GST_DEBUG_OBJECT (bin,
3553 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3554 bin->provided_clock, bin->clock_provider);
3555 provided_clock_p = &bin->provided_clock;
3556 clock_provider_p = &bin->clock_provider;
3557 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3558 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3560 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3561 provided, playing, forward);
3562 GST_OBJECT_UNLOCK (bin);
3568 gst_message_unref (message);
3571 case GST_MESSAGE_CLOCK_PROVIDE:
3575 GST_OBJECT_LOCK (bin);
3576 bin->clock_dirty = TRUE;
3577 /* a new clock is available, post to parent but not
3578 * to the application */
3579 forward = GST_OBJECT_PARENT (bin) != NULL;
3580 GST_OBJECT_UNLOCK (bin);
3586 gst_message_unref (message);
3589 case GST_MESSAGE_ASYNC_START:
3593 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3594 src ? GST_OBJECT_NAME (src) : "(NULL)");
3596 bin_do_message_forward (bin, message);
3598 GST_OBJECT_LOCK (bin);
3599 /* we ignore the message if we are going to <= READY */
3600 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3601 goto ignore_start_message;
3603 /* takes ownership of the message */
3604 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3606 bin_handle_async_start (bin);
3607 GST_OBJECT_UNLOCK (bin);
3610 ignore_start_message:
3612 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3613 gst_element_state_get_name (target));
3614 GST_OBJECT_UNLOCK (bin);
3615 gst_message_unref (message);
3619 case GST_MESSAGE_ASYNC_DONE:
3621 GstClockTime running_time;
3624 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3625 src ? GST_OBJECT_NAME (src) : "(NULL)");
3627 gst_message_parse_async_done (message, &running_time);
3629 bin_do_message_forward (bin, message);
3631 GST_OBJECT_LOCK (bin);
3632 /* ignore messages if we are shutting down */
3633 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3634 goto ignore_done_message;
3636 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3637 /* if there are no more ASYNC_START messages, everybody posted
3638 * a ASYNC_DONE and we can post one on the bus. When checking, we
3639 * don't care who still has a pending ASYNC_START */
3640 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3641 /* nothing found, remove all old ASYNC_DONE messages */
3642 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3644 GST_DEBUG_OBJECT (bin, "async elements commited");
3645 /* when we get an async done message when a state change was busy, we
3646 * need to set the pending_done flag so that at the end of the state
3647 * change we can see if we need to verify pending async elements, hence
3648 * the TRUE argument here. */
3649 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3652 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3654 GST_OBJECT_UNLOCK (bin);
3657 ignore_done_message:
3659 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3660 gst_element_state_get_name (target));
3661 GST_OBJECT_UNLOCK (bin);
3662 gst_message_unref (message);
3666 case GST_MESSAGE_STRUCTURE_CHANGE:
3670 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3672 GST_OBJECT_LOCK (bin);
3674 /* while the pad is busy, avoid following it when doing state changes.
3675 * Don't update the cookie yet, we will do that after the structure
3676 * change finished and we are ready to inspect the new updated
3678 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3681 /* a pad link/unlink ended, signal the state change iterator that we
3682 * need to resync by updating the structure_cookie. */
3683 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3684 GST_MESSAGE_STRUCTURE_CHANGE);
3685 if (!GST_BIN_IS_NO_RESYNC (bin))
3686 bin->priv->structure_cookie++;
3688 GST_OBJECT_UNLOCK (bin);
3691 gst_message_unref (message);
3695 case GST_MESSAGE_NEED_CONTEXT:{
3696 const gchar *context_type;
3699 gst_message_parse_context_type (message, &context_type);
3700 GST_OBJECT_LOCK (bin);
3701 for (l = bin->priv->contexts; l; l = l->next) {
3702 GstContext *tmp = l->data;
3703 const gchar *tmp_type = gst_context_get_context_type (tmp);
3705 if (strcmp (context_type, tmp_type) == 0) {
3706 gst_element_set_context (GST_ELEMENT (src), l->data);
3710 GST_OBJECT_UNLOCK (bin);
3712 /* Forward if we couldn't answer the message */
3716 gst_message_unref (message);
3721 case GST_MESSAGE_HAVE_CONTEXT:{
3722 GstContext *context;
3724 gst_message_parse_have_context (message, &context);
3725 gst_bin_update_context (bin, context);
3726 gst_context_unref (context);
3738 /* Send all other messages upward */
3739 GST_DEBUG_OBJECT (bin, "posting message upward");
3740 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
3745 /* generic struct passed to all query fold methods */
3754 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
3755 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
3757 /* for duration/position we collect all durations/positions and take
3758 * the MAX of all valid results */
3760 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
3768 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3770 gboolean res = FALSE;
3771 GstObject *item = g_value_get_object (vitem);
3772 if (GST_IS_PAD (item))
3773 res = gst_pad_query (GST_PAD (item), fold->query);
3775 res = gst_element_query (GST_ELEMENT (item), fold->query);
3780 g_value_set_boolean (ret, TRUE);
3782 gst_query_parse_duration (fold->query, NULL, &duration);
3784 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
3786 if (duration == -1) {
3787 /* duration query succeeded, but duration is unknown */
3792 if (duration > fold->max)
3793 fold->max = duration;
3800 bin_query_duration_done (GstBin * bin, QueryFold * fold)
3804 gst_query_parse_duration (fold->query, &format, NULL);
3805 /* store max in query result */
3806 gst_query_set_duration (fold->query, format, fold->max);
3808 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
3810 /* FIXME: re-implement duration caching */
3813 GST_OBJECT_LOCK (bin);
3814 bin->messages = g_list_prepend (bin->messages,
3815 gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
3816 GST_OBJECT_UNLOCK (bin);
3821 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3823 gboolean res = FALSE;
3824 GstObject *item = g_value_get_object (vitem);
3825 if (GST_IS_PAD (item))
3826 res = gst_pad_query (GST_PAD (item), fold->query);
3828 res = gst_element_query (GST_ELEMENT (item), fold->query);
3833 g_value_set_boolean (ret, TRUE);
3835 gst_query_parse_position (fold->query, NULL, &position);
3837 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
3839 if (position > fold->max)
3840 fold->max = position;
3847 bin_query_position_done (GstBin * bin, QueryFold * fold)
3851 gst_query_parse_position (fold->query, &format, NULL);
3852 /* store max in query result */
3853 gst_query_set_position (fold->query, format, fold->max);
3855 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
3859 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3861 gboolean res = FALSE;
3862 GstObject *item = g_value_get_object (vitem);
3863 if (GST_IS_PAD (item))
3864 res = gst_pad_query (GST_PAD (item), fold->query);
3866 res = gst_element_query (GST_ELEMENT (item), fold->query);
3868 GstClockTime min, max;
3871 gst_query_parse_latency (fold->query, &live, &min, &max);
3873 GST_DEBUG_OBJECT (item,
3874 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3875 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
3877 /* for the combined latency we collect the MAX of all min latencies and
3878 * the MIN of all max latencies */
3880 if (min > fold->min)
3882 if (fold->max == -1)
3884 else if (max < fold->max)
3886 if (fold->live == FALSE)
3890 g_value_set_boolean (ret, FALSE);
3891 GST_DEBUG_OBJECT (item, "failed query");
3898 bin_query_latency_done (GstBin * bin, QueryFold * fold)
3900 /* store max in query result */
3901 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
3903 GST_DEBUG_OBJECT (bin,
3904 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3905 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
3909 /* generic fold, return first valid result */
3911 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3913 gboolean res = FALSE;
3914 GstObject *item = g_value_get_object (vitem);
3915 if (GST_IS_PAD (item))
3916 res = gst_pad_query (GST_PAD (item), fold->query);
3918 res = gst_element_query (GST_ELEMENT (item), fold->query);
3920 g_value_set_boolean (ret, TRUE);
3921 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
3924 /* and stop as soon as we have a valid result */
3928 /* Perform a query iteration for the given bin. The query is stored in
3929 * QueryFold and iter should be either a GstPad iterator or a
3930 * GstElement iterator. */
3932 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
3933 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
3934 QueryFold fold_data, gboolean default_return)
3936 gboolean res = default_return;
3938 /* set the result of the query to FALSE initially */
3939 g_value_init (&ret, G_TYPE_BOOLEAN);
3940 g_value_set_boolean (&ret, res);
3943 GstIteratorResult ires;
3945 ires = gst_iterator_fold (iter, fold_func, &ret, &fold_data);
3948 case GST_ITERATOR_RESYNC:
3949 gst_iterator_resync (iter);
3951 fold_init (bin, &fold_data);
3952 g_value_set_boolean (&ret, res);
3954 case GST_ITERATOR_OK:
3955 case GST_ITERATOR_DONE:
3956 res = g_value_get_boolean (&ret);
3957 if (fold_done != NULL && res)
3958 fold_done (bin, &fold_data);
3970 gst_bin_query (GstElement * element, GstQuery * query)
3972 GstBin *bin = GST_BIN_CAST (element);
3974 gboolean default_return = FALSE;
3975 gboolean res = FALSE;
3976 gboolean src_pads_query_result = FALSE;
3977 GstIteratorFoldFunction fold_func;
3978 QueryInitFunction fold_init = NULL;
3979 QueryDoneFunction fold_done = NULL;
3980 QueryFold fold_data;
3982 switch (GST_QUERY_TYPE (query)) {
3983 case GST_QUERY_DURATION:
3985 /* FIXME: implement duration caching in GstBin again */
3990 gst_query_parse_duration (query, &qformat, NULL);
3992 /* find cached duration query */
3993 GST_OBJECT_LOCK (bin);
3994 for (cached = bin->messages; cached; cached = g_list_next (cached)) {
3995 GstMessage *message = (GstMessage *) cached->data;
3997 if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION_CHANGED &&
3998 GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
4002 gst_message_parse_duration (message, &format, &duration);
4004 /* if cached same format, copy duration in query result */
4005 if (format == qformat) {
4006 GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
4008 GST_OBJECT_UNLOCK (bin);
4010 gst_query_set_duration (query, qformat, duration);
4016 GST_OBJECT_UNLOCK (bin);
4018 GST_FIXME ("implement duration caching in GstBin again");
4020 /* no cached value found, iterate and collect durations */
4021 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
4022 fold_init = bin_query_min_max_init;
4023 fold_done = bin_query_duration_done;
4026 case GST_QUERY_POSITION:
4028 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
4029 fold_init = bin_query_min_max_init;
4030 fold_done = bin_query_position_done;
4033 case GST_QUERY_LATENCY:
4035 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
4036 fold_init = bin_query_min_max_init;
4037 fold_done = bin_query_latency_done;
4038 default_return = TRUE;
4042 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
4046 fold_data.query = query;
4048 iter = gst_bin_iterate_sinks (bin);
4049 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
4050 query, GST_QUERY_TYPE_NAME (query));
4053 fold_init (bin, &fold_data);
4056 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, fold_data,
4058 gst_iterator_free (iter);
4061 /* Query the source pads of the element */
4062 iter = gst_element_iterate_src_pads (element);
4063 src_pads_query_result =
4064 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
4065 fold_data, default_return);
4066 gst_iterator_free (iter);
4068 if (src_pads_query_result)
4072 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
4078 set_context (const GValue * item, gpointer user_data)
4080 GstElement *element = g_value_get_object (item);
4082 gst_element_set_context (element, user_data);
4086 gst_bin_set_context (GstElement * element, GstContext * context)
4089 GstIterator *children;
4091 g_return_if_fail (GST_IS_BIN (element));
4093 bin = GST_BIN (element);
4095 gst_bin_update_context (bin, context);
4097 children = gst_bin_iterate_elements (bin);
4098 while (gst_iterator_foreach (children, set_context,
4099 context) == GST_ITERATOR_RESYNC)
4100 gst_iterator_resync (children);
4101 gst_iterator_free (children);
4105 compare_name (const GValue * velement, const gchar * name)
4108 GstElement *element = g_value_get_object (velement);
4110 GST_OBJECT_LOCK (element);
4111 eq = strcmp (GST_ELEMENT_NAME (element), name);
4112 GST_OBJECT_UNLOCK (element);
4118 * gst_bin_get_by_name:
4120 * @name: the element name to search for
4122 * Gets the element with the given name from a bin. This
4123 * function recurses into child bins.
4125 * Returns %NULL if no element with the given name is found in the bin.
4127 * MT safe. Caller owns returned reference.
4129 * Returns: (transfer full): the #GstElement with the given name, or %NULL
4132 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4134 GstIterator *children;
4135 GValue result = { 0, };
4136 GstElement *element;
4139 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4141 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4142 GST_ELEMENT_NAME (bin), name);
4144 children = gst_bin_iterate_recurse (bin);
4145 found = gst_iterator_find_custom (children,
4146 (GCompareFunc) compare_name, &result, (gpointer) name);
4147 gst_iterator_free (children);
4150 element = g_value_dup_object (&result);
4151 g_value_unset (&result);
4160 * gst_bin_get_by_name_recurse_up:
4162 * @name: the element name to search for
4164 * Gets the element with the given name from this bin. If the
4165 * element is not found, a recursion is performed on the parent bin.
4168 * - no element with the given name is found in the bin
4170 * MT safe. Caller owns returned reference.
4172 * Returns: (transfer full): the #GstElement with the given name, or %NULL
4175 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4179 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4180 g_return_val_if_fail (name != NULL, NULL);
4182 result = gst_bin_get_by_name (bin, name);
4187 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4189 if (GST_IS_BIN (parent)) {
4190 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4192 gst_object_unref (parent);
4200 compare_interface (const GValue * velement, GValue * interface)
4202 GstElement *element = g_value_get_object (velement);
4203 GType interface_type = (GType) g_value_get_pointer (interface);
4206 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4215 * gst_bin_get_by_interface:
4217 * @iface: the #GType of an interface
4219 * Looks for an element inside the bin that implements the given
4220 * interface. If such an element is found, it returns the element.
4221 * You can cast this element to the given interface afterwards. If you want
4222 * all elements that implement the interface, use
4223 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4225 * MT safe. Caller owns returned reference.
4227 * Returns: (transfer full): A #GstElement inside the bin implementing the interface
4230 gst_bin_get_by_interface (GstBin * bin, GType iface)
4232 GstIterator *children;
4233 GValue result = { 0, };
4234 GstElement *element;
4236 GValue viface = { 0, };
4238 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4239 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4241 g_value_init (&viface, G_TYPE_POINTER);
4242 g_value_set_pointer (&viface, (gpointer) iface);
4244 children = gst_bin_iterate_recurse (bin);
4245 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4247 gst_iterator_free (children);
4250 element = g_value_dup_object (&result);
4251 g_value_unset (&result);
4255 g_value_unset (&viface);
4261 * gst_bin_iterate_all_by_interface:
4263 * @iface: the #GType of an interface
4265 * Looks for all elements inside the bin that implements the given
4266 * interface. You can safely cast all returned elements to the given interface.
4267 * The function recurses inside child bins. The iterator will yield a series
4268 * of #GstElement that should be unreffed after use.
4270 * MT safe. Caller owns returned value.
4272 * Returns: (transfer full): a #GstIterator of #GstElement for all elements
4273 * in the bin implementing the given interface, or %NULL
4276 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4278 GstIterator *children;
4279 GstIterator *result;
4280 GValue viface = { 0, };
4282 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4283 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4285 g_value_init (&viface, G_TYPE_POINTER);
4286 g_value_set_pointer (&viface, (gpointer) iface);
4288 children = gst_bin_iterate_recurse (bin);
4289 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4292 g_value_unset (&viface);