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: (allow-none): the name of the new bin
542 * Creates a new bin with the given name.
544 * Returns: (transfer floating): a new #GstBin
547 gst_bin_new (const gchar * name)
549 return gst_element_factory_make ("bin", name);
553 gst_bin_set_property (GObject * object, guint prop_id,
554 const GValue * value, GParamSpec * pspec)
558 gstbin = GST_BIN_CAST (object);
561 case PROP_ASYNC_HANDLING:
562 GST_OBJECT_LOCK (gstbin);
563 gstbin->priv->asynchandling = g_value_get_boolean (value);
564 GST_OBJECT_UNLOCK (gstbin);
566 case PROP_MESSAGE_FORWARD:
567 GST_OBJECT_LOCK (gstbin);
568 gstbin->priv->message_forward = g_value_get_boolean (value);
569 GST_OBJECT_UNLOCK (gstbin);
572 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
578 gst_bin_get_property (GObject * object, guint prop_id,
579 GValue * value, GParamSpec * pspec)
583 gstbin = GST_BIN_CAST (object);
586 case PROP_ASYNC_HANDLING:
587 GST_OBJECT_LOCK (gstbin);
588 g_value_set_boolean (value, gstbin->priv->asynchandling);
589 GST_OBJECT_UNLOCK (gstbin);
591 case PROP_MESSAGE_FORWARD:
592 GST_OBJECT_LOCK (gstbin);
593 g_value_set_boolean (value, gstbin->priv->message_forward);
594 GST_OBJECT_UNLOCK (gstbin);
597 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
603 /* return the cached index */
605 gst_bin_get_index_func (GstElement * element)
610 bin = GST_BIN_CAST (element);
612 GST_OBJECT_LOCK (bin);
613 if ((result = bin->priv->index))
614 gst_object_ref (result);
615 GST_OBJECT_UNLOCK (bin);
620 /* set the index on all elements in this bin
625 gst_bin_set_index_func (GstElement * element, GstIndex * index)
631 GValue data = { 0, };
633 bin = GST_BIN_CAST (element);
635 GST_OBJECT_LOCK (bin);
636 old = bin->priv->index;
637 if (G_UNLIKELY (old == index))
640 gst_object_ref (index);
641 bin->priv->index = index;
642 GST_OBJECT_UNLOCK (bin);
645 gst_object_unref (old);
647 it = gst_bin_iterate_elements (bin);
649 /* set the index on all elements in the bin */
652 switch (gst_iterator_next (it, &data)) {
653 case GST_ITERATOR_OK:
655 GstElement *child = g_value_get_object (&data);
657 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
658 GST_ELEMENT_NAME (child));
659 gst_element_set_index (child, index);
661 g_value_reset (&data);
664 case GST_ITERATOR_RESYNC:
665 GST_DEBUG_OBJECT (bin, "iterator doing resync");
666 gst_iterator_resync (it);
669 case GST_ITERATOR_DONE:
670 GST_DEBUG_OBJECT (bin, "iterator done");
675 g_value_unset (&data);
676 gst_iterator_free (it);
681 GST_DEBUG_OBJECT (bin, "index was already set");
682 GST_OBJECT_UNLOCK (bin);
688 /* set the clock on all elements in this bin
693 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
699 GValue data = { 0, };
701 bin = GST_BIN_CAST (element);
703 it = gst_bin_iterate_elements (bin);
707 switch (gst_iterator_next (it, &data)) {
708 case GST_ITERATOR_OK:
710 GstElement *child = g_value_get_object (&data);
712 res &= gst_element_set_clock (child, clock);
714 g_value_reset (&data);
717 case GST_ITERATOR_RESYNC:
718 GST_DEBUG_OBJECT (bin, "iterator doing resync");
719 gst_iterator_resync (it);
723 case GST_ITERATOR_DONE:
724 GST_DEBUG_OBJECT (bin, "iterator done");
729 g_value_unset (&data);
730 gst_iterator_free (it);
733 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
738 /* get the clock for this bin by asking all of the children in this bin
740 * The ref of the returned clock in increased so unref after usage.
742 * We loop the elements in state order and pick the last clock we can
743 * get. This makes sure we get a clock from the source.
748 gst_bin_provide_clock_func (GstElement * element)
750 GstClock *result = NULL;
751 GstElement *provider = NULL;
756 GstClock **provided_clock_p;
757 GstElement **clock_provider_p;
759 bin = GST_BIN_CAST (element);
761 GST_OBJECT_LOCK (bin);
762 if (!bin->clock_dirty)
765 GST_DEBUG_OBJECT (bin, "finding new clock");
767 it = gst_bin_sort_iterator_new (bin);
768 GST_OBJECT_UNLOCK (bin);
772 switch (gst_iterator_next (it, &val)) {
773 case GST_ITERATOR_OK:
775 GstElement *child = g_value_get_object (&val);
778 clock = gst_element_provide_clock (child);
780 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
781 clock, GST_ELEMENT_NAME (child));
783 gst_object_unref (result);
784 gst_object_unref (provider);
787 provider = gst_object_ref (child);
790 g_value_reset (&val);
793 case GST_ITERATOR_RESYNC:
794 gst_iterator_resync (it);
797 case GST_ITERATOR_DONE:
802 g_value_unset (&val);
803 gst_iterator_free (it);
805 GST_OBJECT_LOCK (bin);
806 if (!bin->clock_dirty) {
808 gst_object_unref (provider);
810 gst_object_unref (result);
816 provided_clock_p = &bin->provided_clock;
817 clock_provider_p = &bin->clock_provider;
818 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
819 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
820 bin->clock_dirty = FALSE;
821 GST_DEBUG_OBJECT (bin,
822 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
824 /* Provider is not being returned to caller, just the result */
826 gst_object_unref (provider);
827 GST_OBJECT_UNLOCK (bin);
833 if ((result = bin->provided_clock))
834 gst_object_ref (result);
835 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
836 GST_OBJECT_UNLOCK (bin);
843 * functions for manipulating cached messages
848 GstMessageType types;
851 /* check if a message is of given src and type */
853 message_check (GstMessage * message, MessageFind * target)
858 eq &= GST_MESSAGE_SRC (message) == target->src;
860 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
861 GST_LOG ("looking at message %p: %d", message, eq);
867 find_message (GstBin * bin, GstObject * src, GstMessageType types)
875 result = g_list_find_custom (bin->messages, &find,
876 (GCompareFunc) message_check);
879 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
880 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
883 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
884 #ifndef GST_DISABLE_GST_DEBUG
888 for (i = 0; i < 32; i++)
889 if (types & (1U << i))
890 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1U << i));
898 /* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
901 * A message that is cached and has the same SRC and type is replaced
902 * by the given message.
905 bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
911 if ((src = GST_MESSAGE_SRC (message))) {
912 /* first find the previous message posted by this element */
913 if ((previous = find_message (bin, src, types))) {
914 GstMessage *previous_msg;
916 /* if we found a previous message, replace it */
917 previous_msg = previous->data;
918 previous->data = message;
920 GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
921 GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
922 GST_MESSAGE_TYPE_NAME (message));
924 gst_message_unref (previous_msg);
926 /* keep new message */
927 bin->messages = g_list_prepend (bin->messages, message);
929 GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
930 message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
933 GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
934 GST_MESSAGE_TYPE_NAME (message));
936 gst_message_unref (message);
941 /* with LOCK. Remove all messages of given types */
943 bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
951 for (walk = bin->messages; walk; walk = next) {
952 GstMessage *message = (GstMessage *) walk->data;
954 next = g_list_next (walk);
956 if (message_check (message, &find) == 0) {
957 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
958 "deleting message %p of 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);
1293 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1295 bclass = GST_BIN_GET_CLASS (bin);
1297 if (G_UNLIKELY (bclass->add_element == NULL))
1300 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1301 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1302 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1304 result = bclass->add_element (bin, element);
1308 /* ERROR handling */
1311 g_warning ("adding elements to bin '%s' is not supported",
1312 GST_ELEMENT_NAME (bin));
1317 /* remove an element from the bin
1322 gst_bin_remove_func (GstBin * bin, GstElement * element)
1326 gboolean is_sink, is_source, provides_clock, requires_clock;
1327 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1328 GstMessage *clock_message = NULL;
1329 GstClock **provided_clock_p;
1330 GstElement **clock_provider_p;
1332 gboolean other_async, this_async, have_no_preroll;
1333 GstStateChangeReturn ret;
1335 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1337 /* we obviously can't remove ourself from ourself */
1338 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1339 goto removing_itself;
1341 GST_OBJECT_LOCK (bin);
1343 GST_OBJECT_LOCK (element);
1344 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1346 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1349 /* remove the parent ref */
1350 GST_OBJECT_PARENT (element) = NULL;
1352 /* grab element name so we can print it */
1353 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1354 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1356 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1358 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1359 GST_OBJECT_UNLOCK (element);
1363 othersource = FALSE;
1364 otherprovider = FALSE;
1365 otherrequirer = FALSE;
1366 have_no_preroll = FALSE;
1367 /* iterate the elements, we collect which ones are async and no_preroll. We
1368 * also remove the element when we find it. */
1369 for (walk = bin->children; walk; walk = next) {
1370 GstElement *child = GST_ELEMENT_CAST (walk->data);
1372 next = g_list_next (walk);
1374 if (child == element) {
1376 /* remove the element */
1377 bin->children = g_list_delete_link (bin->children, walk);
1379 gboolean child_sink, child_source, child_provider, child_requirer;
1381 GST_OBJECT_LOCK (child);
1382 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1383 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1385 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1387 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1388 /* when we remove a sink, check if there are other sinks. */
1389 if (is_sink && !othersink && child_sink)
1391 if (is_source && !othersource && child_source)
1393 if (provides_clock && !otherprovider && child_provider)
1394 otherprovider = TRUE;
1395 if (requires_clock && !otherrequirer && child_requirer)
1396 otherrequirer = TRUE;
1397 /* check if we have NO_PREROLL children */
1398 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1399 have_no_preroll = TRUE;
1400 GST_OBJECT_UNLOCK (child);
1404 /* the element must have been in the bin's list of children */
1405 if (G_UNLIKELY (!found))
1408 /* we now removed the element from the list of elements, increment the cookie
1409 * so that others can detect a change in the children list. */
1411 bin->children_cookie++;
1412 if (!GST_BIN_IS_NO_RESYNC (bin))
1413 bin->priv->structure_cookie++;
1415 if (is_sink && !othersink) {
1416 /* we're not a sink anymore */
1417 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1418 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1420 if (is_source && !othersource) {
1421 /* we're not a source anymore */
1422 GST_DEBUG_OBJECT (bin, "we removed the last source");
1423 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1425 if (provides_clock && !otherprovider) {
1426 /* we're not a clock provider anymore */
1427 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1428 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1430 if (requires_clock && !otherrequirer) {
1431 /* we're not a clock requirer anymore */
1432 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1433 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1436 /* if the clock provider for this element is removed, we lost
1437 * the clock as well, we need to inform the parent of this
1438 * so that it can select a new clock */
1439 if (bin->clock_provider == element) {
1440 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1441 bin->clock_dirty = TRUE;
1443 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1444 provided_clock_p = &bin->provided_clock;
1445 clock_provider_p = &bin->clock_provider;
1446 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1447 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1450 /* remove messages for the element, if there was a pending ASYNC_START
1451 * message we must see if removing the element caused the bin to lose its
1454 other_async = FALSE;
1455 for (walk = bin->messages; walk; walk = next) {
1456 GstMessage *message = (GstMessage *) walk->data;
1457 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1460 next = g_list_next (walk);
1463 switch (GST_MESSAGE_TYPE (message)) {
1464 case GST_MESSAGE_ASYNC_START:
1470 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1472 case GST_MESSAGE_STRUCTURE_CHANGE:
1476 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1478 /* it's unlikely that this message is still in the list of messages
1479 * because this would mean that a link/unlink is busy in another thread
1480 * while we remove the element. We still have to remove the message
1481 * because we might not receive the done message anymore when the element
1482 * is removed from the bin. */
1483 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1484 if (owner == element)
1495 /* delete all message types */
1496 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1497 message, elem_name);
1498 bin->messages = g_list_delete_link (bin->messages, walk);
1499 gst_message_unref (message);
1503 /* get last return */
1504 ret = GST_STATE_RETURN (bin);
1506 /* no need to update the state if we are in error */
1507 if (ret == GST_STATE_CHANGE_FAILURE)
1508 goto no_state_recalc;
1510 if (!other_async && this_async) {
1511 /* all other elements were not async and we removed the async one,
1512 * handle the async-done case because we are not async anymore now. */
1513 GST_DEBUG_OBJECT (bin,
1514 "we removed the last async element, have no_preroll %d",
1517 /* the current state return of the bin depends on if there are no_preroll
1518 * elements in the pipeline or not */
1519 if (have_no_preroll)
1520 ret = GST_STATE_CHANGE_NO_PREROLL;
1522 ret = GST_STATE_CHANGE_SUCCESS;
1524 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1526 GST_DEBUG_OBJECT (bin,
1527 "recalc state preroll: %d, other async: %d, this async %d",
1528 have_no_preroll, other_async, this_async);
1530 if (have_no_preroll) {
1531 ret = GST_STATE_CHANGE_NO_PREROLL;
1532 } else if (other_async) {
1533 /* there are other async elements and we were not doing an async state
1534 * change, change our pending state and go async */
1535 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1536 GST_STATE_NEXT (bin) = GST_STATE (bin);
1537 GST_STATE_PENDING (bin) = GST_STATE (bin);
1539 ret = GST_STATE_CHANGE_ASYNC;
1541 GST_STATE_RETURN (bin) = ret;
1545 gst_element_set_bus (element, NULL);
1546 /* Clear the clock we provided to the element */
1547 gst_element_set_clock (element, NULL);
1548 GST_OBJECT_UNLOCK (bin);
1551 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1553 /* unlink all linked pads */
1554 it = gst_element_iterate_pads (element);
1555 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1556 gst_iterator_free (it);
1558 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1561 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1562 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1566 /* element is really out of our control now */
1567 gst_object_unref (element);
1571 /* ERROR handling */
1574 GST_OBJECT_LOCK (bin);
1575 g_warning ("Cannot remove bin '%s' from itself", GST_ELEMENT_NAME (bin));
1576 GST_OBJECT_UNLOCK (bin);
1581 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1582 GST_ELEMENT_NAME (bin));
1583 GST_OBJECT_UNLOCK (element);
1584 GST_OBJECT_UNLOCK (bin);
1593 * @element: (transfer none): the #GstElement to remove
1595 * Removes the element from the bin, unparenting it as well.
1596 * Unparenting the element means that the element will be dereferenced,
1597 * so if the bin holds the only reference to the element, the element
1598 * will be freed in the process of removing it from the bin. If you
1599 * want the element to still exist after removing, you need to call
1600 * gst_object_ref() before removing it from the bin.
1602 * If the element's pads are linked to other pads, the pads will be unlinked
1603 * before the element is removed from the bin.
1607 * Returns: %TRUE if the element could be removed, %FALSE if
1608 * the bin does not want to remove the element.
1611 gst_bin_remove (GstBin * bin, GstElement * element)
1613 GstBinClass *bclass;
1616 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1617 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1618 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1620 bclass = GST_BIN_GET_CLASS (bin);
1622 if (G_UNLIKELY (bclass->remove_element == NULL))
1625 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1626 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1628 result = bclass->remove_element (bin, element);
1632 /* ERROR handling */
1635 g_warning ("removing elements from bin '%s' is not supported",
1636 GST_ELEMENT_NAME (bin));
1642 * gst_bin_iterate_elements:
1645 * Gets an iterator for the elements in this bin.
1647 * MT safe. Caller owns returned value.
1649 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1653 gst_bin_iterate_elements (GstBin * bin)
1655 GstIterator *result;
1657 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1659 GST_OBJECT_LOCK (bin);
1660 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1661 GST_OBJECT_GET_LOCK (bin),
1662 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1663 GST_OBJECT_UNLOCK (bin);
1668 static GstIteratorItem
1669 iterate_child_recurse (GstIterator * it, const GValue * item)
1671 GstElement *child = g_value_get_object (item);
1673 if (GST_IS_BIN (child)) {
1674 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1676 gst_iterator_push (it, other);
1678 return GST_ITERATOR_ITEM_PASS;
1682 * gst_bin_iterate_recurse:
1685 * Gets an iterator for the elements in this bin.
1686 * This iterator recurses into GstBin children.
1688 * MT safe. Caller owns returned value.
1690 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1694 gst_bin_iterate_recurse (GstBin * bin)
1696 GstIterator *result;
1698 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1700 GST_OBJECT_LOCK (bin);
1701 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1702 GST_OBJECT_GET_LOCK (bin),
1703 &bin->children_cookie,
1705 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1706 GST_OBJECT_UNLOCK (bin);
1711 /* returns 0 when TRUE because this is a GCompareFunc */
1714 bin_element_is_sink (GstElement * child, GstBin * bin)
1718 /* we lock the child here for the remainder of the function to
1719 * get its name and flag safely. */
1720 GST_OBJECT_LOCK (child);
1721 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1723 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1724 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1726 GST_OBJECT_UNLOCK (child);
1727 return is_sink ? 0 : 1;
1731 sink_iterator_filter (const GValue * vchild, GValue * vbin)
1733 GstBin *bin = g_value_get_object (vbin);
1734 GstElement *child = g_value_get_object (vchild);
1736 return (bin_element_is_sink (child, bin));
1740 * gst_bin_iterate_sinks:
1743 * Gets an iterator for all elements in the bin that have the
1744 * #GST_ELEMENT_FLAG_SINK flag set.
1746 * MT safe. Caller owns returned value.
1748 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1752 gst_bin_iterate_sinks (GstBin * bin)
1754 GstIterator *children;
1755 GstIterator *result;
1756 GValue vbin = { 0, };
1758 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1760 g_value_init (&vbin, GST_TYPE_BIN);
1761 g_value_set_object (&vbin, bin);
1763 children = gst_bin_iterate_elements (bin);
1764 result = gst_iterator_filter (children,
1765 (GCompareFunc) sink_iterator_filter, &vbin);
1767 g_value_unset (&vbin);
1772 /* returns 0 when TRUE because this is a GCompareFunc */
1775 bin_element_is_src (GstElement * child, GstBin * bin)
1779 /* we lock the child here for the remainder of the function to
1780 * get its name and other info safely. */
1781 GST_OBJECT_LOCK (child);
1782 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1784 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1785 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
1787 GST_OBJECT_UNLOCK (child);
1788 return is_src ? 0 : 1;
1792 src_iterator_filter (const GValue * vchild, GValue * vbin)
1794 GstBin *bin = g_value_get_object (vbin);
1795 GstElement *child = g_value_get_object (vchild);
1797 return (bin_element_is_src (child, bin));
1801 * gst_bin_iterate_sources:
1804 * Gets an iterator for all elements in the bin that have the
1805 * #GST_ELEMENT_FLAG_SOURCE flag set.
1807 * MT safe. Caller owns returned value.
1809 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1813 gst_bin_iterate_sources (GstBin * bin)
1815 GstIterator *children;
1816 GstIterator *result;
1817 GValue vbin = { 0, };
1819 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1821 g_value_init (&vbin, GST_TYPE_BIN);
1822 g_value_set_object (&vbin, bin);
1824 children = gst_bin_iterate_elements (bin);
1825 result = gst_iterator_filter (children,
1826 (GCompareFunc) src_iterator_filter, &vbin);
1828 g_value_unset (&vbin);
1836 static GstStateChangeReturn
1837 gst_bin_get_state_func (GstElement * element, GstState * state,
1838 GstState * pending, GstClockTime timeout)
1840 GstStateChangeReturn ret;
1842 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
1845 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
1851 /***********************************************
1852 * Topologically sorted iterator
1853 * see http://en.wikipedia.org/wiki/Topological_sorting
1855 * For each element in the graph, an entry is kept in a HashTable
1856 * with its number of srcpad connections (degree).
1857 * We then change state of all elements without dependencies
1858 * (degree 0) and decrement the degree of all elements connected
1859 * on the sinkpads. When an element reaches degree 0, its state is
1861 * When all elements are handled the algorithm stops.
1863 typedef struct _GstBinSortIterator
1866 GQueue queue; /* elements queued for state change */
1867 GstBin *bin; /* bin we iterate */
1868 gint mode; /* adding or removing dependency */
1869 GstElement *best; /* next element with least dependencies */
1870 gint best_deg; /* best degree */
1871 GHashTable *hash; /* hashtable with element dependencies */
1872 gboolean dirty; /* we detected structure change */
1873 } GstBinSortIterator;
1876 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
1877 GstBinSortIterator * copy)
1879 GHashTableIter iter;
1880 gpointer key, value;
1882 copy->queue = it->queue;
1883 g_queue_foreach (©->queue, (GFunc) gst_object_ref, NULL);
1885 copy->bin = gst_object_ref (it->bin);
1887 copy->best = gst_object_ref (it->best);
1889 copy->hash = g_hash_table_new (NULL, NULL);
1890 g_hash_table_iter_init (&iter, it->hash);
1891 while (g_hash_table_iter_next (&iter, &key, &value))
1892 g_hash_table_insert (copy->hash, key, value);
1895 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
1896 #define HASH_SET_DEGREE(bit, elem, deg) \
1897 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
1898 #define HASH_GET_DEGREE(bit, elem) \
1899 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
1901 /* add element to queue of next elements in the iterator.
1902 * We push at the tail to give higher priority elements a
1905 add_to_queue (GstBinSortIterator * bit, GstElement * element)
1907 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
1908 GST_ELEMENT_NAME (element));
1909 gst_object_ref (element);
1910 g_queue_push_tail (&bit->queue, element);
1911 HASH_SET_DEGREE (bit, element, -1);
1915 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
1919 if ((find = g_queue_find (&bit->queue, element))) {
1920 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
1921 GST_ELEMENT_NAME (element));
1923 g_queue_delete_link (&bit->queue, find);
1924 gst_object_unref (element);
1926 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
1927 GST_ELEMENT_NAME (element));
1931 /* clear the queue, unref all objects as we took a ref when
1932 * we added them to the queue */
1934 clear_queue (GQueue * queue)
1938 while ((p = g_queue_pop_head (queue)))
1939 gst_object_unref (p);
1942 /* set all degrees to 0. Elements marked as a sink are
1943 * added to the queue immediately. Since we only look at the SINK flag of the
1944 * element, it is possible that we add non-sinks to the queue. These will be
1945 * removed from the queue again when we can prove that it provides data for some
1948 reset_degree (GstElement * element, GstBinSortIterator * bit)
1952 /* sinks are added right away */
1953 GST_OBJECT_LOCK (element);
1954 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1955 GST_OBJECT_UNLOCK (element);
1958 add_to_queue (bit, element);
1960 /* others are marked with 0 and handled when sinks are done */
1961 HASH_SET_DEGREE (bit, element, 0);
1965 /* adjust the degree of all elements connected to the given
1966 * element. If a degree of an element drops to 0, it is
1967 * added to the queue of elements to schedule next.
1969 * We have to make sure not to cross the bin boundary this element
1973 update_degree (GstElement * element, GstBinSortIterator * bit)
1975 gboolean linked = FALSE;
1977 GST_OBJECT_LOCK (element);
1978 /* don't touch degree if element has no sinkpads */
1979 if (element->numsinkpads != 0) {
1980 /* loop over all sinkpads, decrement degree for all connected
1981 * elements in this bin */
1984 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
1987 pad = GST_PAD_CAST (pads->data);
1989 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
1990 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
1991 GST_MESSAGE_STRUCTURE_CHANGE))) {
1992 /* mark the iterator as dirty because we won't be updating the degree
1993 * of the peer parent now. This would result in the 'loop detected'
1994 * later on because the peer parent element could become the best next
1995 * element with a degree > 0. We will simply continue our state
1996 * changes and we'll eventually resync when the unlink completed and
1997 * the iterator cookie is updated. */
2002 if ((peer = gst_pad_get_peer (pad))) {
2003 GstElement *peer_element;
2005 if ((peer_element = gst_pad_get_parent_element (peer))) {
2006 GST_OBJECT_LOCK (peer_element);
2007 /* check that we don't go outside of this bin */
2008 if (GST_OBJECT_CAST (peer_element)->parent ==
2009 GST_OBJECT_CAST (bit->bin)) {
2010 gint old_deg, new_deg;
2012 old_deg = HASH_GET_DEGREE (bit, peer_element);
2014 /* check to see if we added an element as sink that was not really a
2015 * sink because it was connected to some other element. */
2016 if (old_deg == -1) {
2017 remove_from_queue (bit, peer_element);
2020 new_deg = old_deg + bit->mode;
2022 GST_DEBUG_OBJECT (bit->bin,
2023 "change element %s, degree %d->%d, linked to %s",
2024 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
2025 GST_ELEMENT_NAME (element));
2027 /* update degree, it is possible that an element was in 0 and
2028 * reaches -1 here. This would mean that the element had no sinkpads
2029 * but became linked while the state change was happening. We will
2030 * resync on this with the structure change message. */
2032 /* degree hit 0, add to queue */
2033 add_to_queue (bit, peer_element);
2035 HASH_SET_DEGREE (bit, peer_element, new_deg);
2039 GST_OBJECT_UNLOCK (peer_element);
2040 gst_object_unref (peer_element);
2042 gst_object_unref (peer);
2047 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2048 GST_ELEMENT_NAME (element));
2050 GST_OBJECT_UNLOCK (element);
2053 /* find the next best element not handled yet. This is the one
2054 * with the lowest non-negative degree */
2056 find_element (GstElement * element, GstBinSortIterator * bit)
2060 /* element is already handled */
2061 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2064 /* first element or element with smaller degree */
2065 if (bit->best == NULL || bit->best_deg > degree) {
2066 bit->best = element;
2067 bit->best_deg = degree;
2071 /* get next element in iterator. */
2072 static GstIteratorResult
2073 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2076 GstBin *bin = bit->bin;
2078 /* empty queue, we have to find a next best element */
2079 if (g_queue_is_empty (&bit->queue)) {
2081 bit->best_deg = G_MAXINT;
2082 g_list_foreach (bin->children, (GFunc) find_element, bit);
2083 if ((best = bit->best)) {
2084 /* when we detected an unlink, don't warn because our degrees might be
2085 * screwed up. We will resync later */
2086 if (bit->best_deg != 0 && !bit->dirty) {
2087 /* we don't fail on this one yet */
2088 GST_WARNING_OBJECT (bin, "loop dected in graph");
2089 g_warning ("loop detected in the graph of bin '%s'!!",
2090 GST_ELEMENT_NAME (bin));
2092 /* best unhandled element, schedule as next element */
2093 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2094 GST_ELEMENT_NAME (best));
2095 HASH_SET_DEGREE (bit, best, -1);
2096 g_value_set_object (result, best);
2098 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2099 /* no more unhandled elements, we are done */
2100 return GST_ITERATOR_DONE;
2103 /* everything added to the queue got reffed */
2104 best = g_queue_pop_head (&bit->queue);
2105 g_value_set_object (result, best);
2106 gst_object_unref (best);
2109 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2110 /* update degrees of linked elements */
2111 update_degree (best, bit);
2113 return GST_ITERATOR_OK;
2116 /* clear queues, recalculate the degrees and restart. */
2118 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2120 GstBin *bin = bit->bin;
2122 GST_DEBUG_OBJECT (bin, "resync");
2124 clear_queue (&bit->queue);
2126 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2127 /* calc degrees, incrementing */
2129 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2130 /* for the rest of the function we decrement the degrees */
2134 /* clear queues, unref bin and free iterator. */
2136 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2138 GstBin *bin = bit->bin;
2140 GST_DEBUG_OBJECT (bin, "free");
2141 clear_queue (&bit->queue);
2142 g_hash_table_destroy (bit->hash);
2143 gst_object_unref (bin);
2146 /* should be called with the bin LOCK held */
2147 static GstIterator *
2148 gst_bin_sort_iterator_new (GstBin * bin)
2150 GstBinSortIterator *result;
2152 /* we don't need an ItemFunction because we ref the items in the _next
2154 result = (GstBinSortIterator *)
2155 gst_iterator_new (sizeof (GstBinSortIterator),
2157 GST_OBJECT_GET_LOCK (bin),
2158 &bin->priv->structure_cookie,
2159 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2160 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2161 (GstIteratorItemFunction) NULL,
2162 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2163 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2164 g_queue_init (&result->queue);
2165 result->hash = g_hash_table_new (NULL, NULL);
2166 gst_object_ref (bin);
2168 gst_bin_sort_iterator_resync (result);
2170 return (GstIterator *) result;
2174 * gst_bin_iterate_sorted:
2177 * Gets an iterator for the elements in this bin in topologically
2178 * sorted order. This means that the elements are returned from
2179 * the most downstream elements (sinks) to the sources.
2181 * This function is used internally to perform the state changes
2182 * of the bin elements and for clock selection.
2184 * MT safe. Caller owns returned value.
2186 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
2190 gst_bin_iterate_sorted (GstBin * bin)
2192 GstIterator *result;
2194 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2196 GST_OBJECT_LOCK (bin);
2197 result = gst_bin_sort_iterator_new (bin);
2198 GST_OBJECT_UNLOCK (bin);
2203 static GstStateChangeReturn
2204 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2205 GstClockTime base_time, GstClockTime start_time, GstState current,
2208 GstStateChangeReturn ret;
2209 GstState child_current, child_pending;
2213 GST_STATE_LOCK (element);
2215 GST_OBJECT_LOCK (element);
2216 /* set base_time and start time on child */
2217 GST_ELEMENT_START_TIME (element) = start_time;
2218 element->base_time = base_time;
2219 /* peel off the locked flag */
2220 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2221 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2222 ret = GST_STATE_RETURN (element);
2223 child_current = GST_STATE (element);
2224 child_pending = GST_STATE_PENDING (element);
2225 GST_OBJECT_UNLOCK (element);
2227 /* skip locked elements */
2228 if (G_UNLIKELY (locked))
2231 /* if the element was no preroll, just start changing the state regardless
2232 * if it had async elements (in the case of a bin) because they won't preroll
2234 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2235 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2239 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2240 "current %s pending %s, desired next %s",
2241 gst_element_state_get_name (child_current),
2242 gst_element_state_get_name (child_pending),
2243 gst_element_state_get_name (next));
2245 /* always recurse into bins so that we can set the base time */
2246 if (GST_IS_BIN (element))
2249 /* Try not to change the state of elements that are already in the state we're
2251 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2252 /* child is already at the requested state, return previous return. Note that
2253 * if the child has a pending state to next, we will still call the
2254 * set_state function */
2256 } else if (next > current) {
2257 /* upward state change */
2258 if (child_pending == GST_STATE_VOID_PENDING) {
2259 /* .. and the child is not busy doing anything */
2260 if (child_current > next) {
2261 /* .. and is already past the requested state, assume it got there
2263 ret = GST_STATE_CHANGE_SUCCESS;
2266 } else if (child_pending > child_current) {
2267 /* .. and the child is busy going upwards */
2268 if (child_current >= next) {
2269 /* .. and is already past the requested state, assume it got there
2271 ret = GST_STATE_CHANGE_SUCCESS;
2275 /* .. and the child is busy going downwards */
2276 if (child_current > next) {
2277 /* .. and is already past the requested state, assume it got there
2279 ret = GST_STATE_CHANGE_SUCCESS;
2283 } else if (next < current) {
2284 /* downward state change */
2285 if (child_pending == GST_STATE_VOID_PENDING) {
2286 /* .. and the child is not busy doing anything */
2287 if (child_current < next) {
2288 /* .. and is already past the requested state, assume it got there
2290 ret = GST_STATE_CHANGE_SUCCESS;
2293 } else if (child_pending < child_current) {
2294 /* .. and the child is busy going downwards */
2295 if (child_current <= next) {
2296 /* .. and is already past the requested state, assume it got there
2298 ret = GST_STATE_CHANGE_SUCCESS;
2302 /* .. and the child is busy going upwards */
2303 if (child_current < next) {
2304 /* .. and is already past the requested state, assume it got there
2306 ret = GST_STATE_CHANGE_SUCCESS;
2313 GST_OBJECT_LOCK (bin);
2314 /* the element was busy with an upwards async state change, we must wait for
2315 * an ASYNC_DONE message before we attemp to change the state. */
2317 find_message (bin, GST_OBJECT_CAST (element),
2318 GST_MESSAGE_ASYNC_START))) {
2319 #ifndef GST_DISABLE_GST_DEBUG
2320 GstMessage *message = GST_MESSAGE_CAST (found->data);
2322 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2323 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2325 /* only wait for upward state changes */
2326 if (next > current) {
2327 /* We found an async element check if we can force its state to change or
2328 * if we have to wait for it to preroll. */
2332 GST_OBJECT_UNLOCK (bin);
2335 GST_DEBUG_OBJECT (bin,
2336 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2337 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2338 GST_TIME_ARGS (base_time));
2341 ret = gst_element_set_state (element, next);
2343 GST_STATE_UNLOCK (element);
2349 GST_DEBUG_OBJECT (element,
2350 "element is locked, return previous return %s",
2351 gst_element_state_change_return_get_name (ret));
2352 GST_STATE_UNLOCK (element);
2357 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2358 "skipping transition from %s to %s",
2359 gst_element_state_get_name (child_current),
2360 gst_element_state_get_name (next));
2361 GST_STATE_UNLOCK (element);
2366 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2367 GST_OBJECT_UNLOCK (bin);
2368 GST_STATE_UNLOCK (element);
2369 return GST_STATE_CHANGE_ASYNC;
2373 /* gst_iterator_fold functions for pads_activate
2374 * Stop the iterator if activating one pad failed. */
2376 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2378 GstPad *pad = g_value_get_object (vpad);
2379 gboolean cont = TRUE;
2381 if (!(cont = gst_pad_set_active (pad, *active)))
2382 g_value_set_boolean (ret, FALSE);
2387 /* returns false on error or early cutout of the fold, true if all
2388 * pads in @iter were (de)activated successfully. */
2390 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2392 GstIteratorResult ires;
2395 /* no need to unset this later, it's just a boolean */
2396 g_value_init (&ret, G_TYPE_BOOLEAN);
2397 g_value_set_boolean (&ret, TRUE);
2400 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2403 case GST_ITERATOR_RESYNC:
2404 /* need to reset the result again */
2405 g_value_set_boolean (&ret, TRUE);
2406 gst_iterator_resync (iter);
2408 case GST_ITERATOR_DONE:
2409 /* all pads iterated, return collected value */
2412 /* iterator returned _ERROR or premature end with _OK,
2413 * mark an error and exit */
2414 g_value_set_boolean (&ret, FALSE);
2419 /* return collected value */
2420 return g_value_get_boolean (&ret);
2423 /* is called with STATE_LOCK
2426 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2431 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2433 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2434 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2435 gst_iterator_free (iter);
2436 if (G_UNLIKELY (!fold_ok))
2439 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2446 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2452 * gst_bin_recalculate_latency:
2455 * Query @bin for the current latency using and reconfigures this latency to all the
2456 * elements with a LATENCY event.
2458 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2459 * is posted on the bus.
2461 * This function simply emits the 'do-latency' signal so any custom latency
2462 * calculations will be performed.
2464 * Returns: %TRUE if the latency could be queried and reconfigured.
2467 gst_bin_recalculate_latency (GstBin * bin)
2471 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2472 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2478 gst_bin_do_latency_func (GstBin * bin)
2481 GstElement *element;
2482 GstClockTime min_latency, max_latency;
2485 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2487 element = GST_ELEMENT_CAST (bin);
2489 GST_DEBUG_OBJECT (element, "querying latency");
2491 query = gst_query_new_latency ();
2492 if ((res = gst_element_query (element, query))) {
2495 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2497 GST_DEBUG_OBJECT (element,
2498 "got min latency %" GST_TIME_FORMAT ", max latency %"
2499 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2500 GST_TIME_ARGS (max_latency), live);
2502 if (max_latency < min_latency) {
2503 /* this is an impossible situation, some parts of the pipeline might not
2504 * work correctly. We post a warning for now. */
2505 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2506 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2507 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2508 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2511 /* configure latency on elements */
2512 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2514 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2515 GST_TIME_ARGS (min_latency));
2517 GST_WARNING_OBJECT (element,
2518 "did not really configure latency of %" GST_TIME_FORMAT,
2519 GST_TIME_ARGS (min_latency));
2522 /* this is not a real problem, we just don't configure any latency. */
2523 GST_WARNING_OBJECT (element, "failed to query latency");
2525 gst_query_unref (query);
2531 gst_bin_post_message (GstElement * element, GstMessage * msg)
2533 GstElementClass *pklass = (GstElementClass *) parent_class;
2536 ret = pklass->post_message (element, gst_message_ref (msg));
2538 if (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_STATE_CHANGED &&
2539 GST_MESSAGE_SRC (msg) == GST_OBJECT_CAST (element)) {
2540 GstState newstate, pending;
2542 gst_message_parse_state_changed (msg, NULL, &newstate, &pending);
2543 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING) {
2544 GST_BIN_CAST (element)->priv->posted_playing = TRUE;
2545 bin_do_eos (GST_BIN_CAST (element));
2547 GST_BIN_CAST (element)->priv->posted_playing = FALSE;
2551 gst_message_unref (msg);
2557 reset_state (const GValue * data, gpointer user_data)
2559 GstElement *e = g_value_get_object (data);
2560 GstState state = GPOINTER_TO_INT (user_data);
2562 if (gst_element_set_state (e, state) == GST_STATE_CHANGE_FAILURE)
2563 GST_WARNING_OBJECT (e, "Failed to switch back down to %s",
2564 gst_element_state_get_name (state));
2567 static GstStateChangeReturn
2568 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2571 GstStateChangeReturn ret;
2572 GstState current, next;
2573 gboolean have_async;
2574 gboolean have_no_preroll;
2575 GstClockTime base_time, start_time;
2578 GValue data = { 0, };
2580 /* we don't need to take the STATE_LOCK, it is already taken */
2581 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2582 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2584 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2585 "changing state of children from %s to %s",
2586 gst_element_state_get_name (current), gst_element_state_get_name (next));
2588 bin = GST_BIN_CAST (element);
2591 case GST_STATE_PLAYING:
2595 GST_OBJECT_LOCK (bin);
2596 toplevel = BIN_IS_TOPLEVEL (bin);
2597 GST_OBJECT_UNLOCK (bin);
2600 gst_bin_recalculate_latency (bin);
2603 case GST_STATE_PAUSED:
2604 /* Clear EOS list on next PAUSED */
2605 GST_OBJECT_LOCK (bin);
2606 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2607 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2608 bin->priv->posted_eos = FALSE;
2609 if (current == GST_STATE_READY)
2610 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2611 GST_OBJECT_UNLOCK (bin);
2612 if (current == GST_STATE_READY)
2613 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2614 goto activate_failure;
2616 case GST_STATE_READY:
2617 /* Clear message list on next READY */
2618 GST_OBJECT_LOCK (bin);
2619 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2620 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2621 GST_OBJECT_UNLOCK (bin);
2622 /* We might not have reached PAUSED yet due to async errors,
2623 * make sure to always deactivate the pads nonetheless */
2624 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2625 goto activate_failure;
2627 case GST_STATE_NULL:
2628 if (current == GST_STATE_READY) {
2631 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2632 goto activate_failure;
2634 /* Remove all non-persistent contexts */
2635 GST_OBJECT_LOCK (bin);
2636 for (l = bin->priv->contexts; l;) {
2637 GstContext *context = l->data;
2639 if (!gst_context_is_persistent (context)) {
2642 gst_context_unref (context);
2644 bin->priv->contexts = g_list_delete_link (bin->priv->contexts, l);
2650 GST_OBJECT_UNLOCK (bin);
2657 /* this flag is used to make the async state changes return immediately. We
2658 * don't want them to interfere with this state change */
2659 GST_OBJECT_LOCK (bin);
2660 bin->polling = TRUE;
2661 GST_OBJECT_UNLOCK (bin);
2663 /* iterate in state change order */
2664 it = gst_bin_iterate_sorted (bin);
2666 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2667 * Note how we don't reset this value when a resync happens, the reason being
2668 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2669 * even after a resync when the async element is gone */
2673 /* take base_time */
2674 base_time = gst_element_get_base_time (element);
2675 start_time = gst_element_get_start_time (element);
2677 have_no_preroll = FALSE;
2681 switch (gst_iterator_next (it, &data)) {
2682 case GST_ITERATOR_OK:
2686 child = g_value_get_object (&data);
2688 /* set state and base_time now */
2689 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2693 case GST_STATE_CHANGE_SUCCESS:
2694 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2695 "child '%s' changed state to %d(%s) successfully",
2696 GST_ELEMENT_NAME (child), next,
2697 gst_element_state_get_name (next));
2699 case GST_STATE_CHANGE_ASYNC:
2701 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2702 "child '%s' is changing state asynchronously to %s",
2703 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2707 case GST_STATE_CHANGE_FAILURE:{
2710 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2711 "child '%s' failed to go to state %d(%s)",
2712 GST_ELEMENT_NAME (child),
2713 next, gst_element_state_get_name (next));
2715 /* Only fail if the child is still inside
2716 * this bin. It might've been removed already
2717 * because of the error by the bin subclass
2718 * to ignore the error. */
2719 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2720 if (parent == GST_OBJECT_CAST (element)) {
2721 /* element is still in bin, really error now */
2722 gst_object_unref (parent);
2725 /* child removed from bin, let the resync code redo the state
2727 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2728 "child '%s' was removed from the bin",
2729 GST_ELEMENT_NAME (child));
2732 gst_object_unref (parent);
2736 case GST_STATE_CHANGE_NO_PREROLL:
2737 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2738 "child '%s' changed state to %d(%s) successfully without preroll",
2739 GST_ELEMENT_NAME (child), next,
2740 gst_element_state_get_name (next));
2741 have_no_preroll = TRUE;
2744 g_assert_not_reached ();
2747 g_value_reset (&data);
2750 case GST_ITERATOR_RESYNC:
2751 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
2752 gst_iterator_resync (it);
2755 case GST_ITERATOR_DONE:
2756 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
2762 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
2763 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
2766 if (have_no_preroll) {
2767 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2768 "we have NO_PREROLL elements %s -> NO_PREROLL",
2769 gst_element_state_change_return_get_name (ret));
2770 ret = GST_STATE_CHANGE_NO_PREROLL;
2771 } else if (have_async) {
2772 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2773 "we have ASYNC elements %s -> ASYNC",
2774 gst_element_state_change_return_get_name (ret));
2775 ret = GST_STATE_CHANGE_ASYNC;
2779 g_value_unset (&data);
2780 gst_iterator_free (it);
2782 GST_OBJECT_LOCK (bin);
2783 bin->polling = FALSE;
2784 /* it's possible that we did not get ASYNC from the children while the bin is
2785 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
2786 * itself as the source. In that case we still want to check if the state
2787 * change completed. */
2788 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
2789 /* no element returned ASYNC and there are no pending async_done messages,
2790 * we can just complete. */
2791 GST_DEBUG_OBJECT (bin, "no async elements");
2794 /* when we get here an ASYNC element was found */
2795 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
2796 /* we ignore ASYNC state changes when we go to READY or NULL */
2797 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
2798 gst_element_state_get_name (GST_STATE_TARGET (bin)));
2802 GST_DEBUG_OBJECT (bin, "check async elements");
2803 /* check if all elements managed to commit their state already */
2804 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
2805 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
2806 * all the elements commited their state while we were doing the state
2807 * change. We will still return ASYNC for consistency but we commit the
2808 * state already so that a _get_state() will return immediately. */
2809 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
2811 GST_DEBUG_OBJECT (bin, "async elements commited");
2812 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
2813 GST_CLOCK_TIME_NONE);
2817 bin->priv->pending_async_done = FALSE;
2818 GST_OBJECT_UNLOCK (bin);
2820 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2821 "done changing bin's state from %s to %s, now in %s, ret %s",
2822 gst_element_state_get_name (current),
2823 gst_element_state_get_name (next),
2824 gst_element_state_get_name (GST_STATE (element)),
2825 gst_element_state_change_return_get_name (ret));
2832 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
2833 "failure (de)activating src pads");
2834 return GST_STATE_CHANGE_FAILURE;
2839 if (current < next) {
2840 GstIterator *it = gst_bin_iterate_sorted (GST_BIN (element));
2841 GstIteratorResult ret;
2843 GST_DEBUG_OBJECT (element,
2844 "Bin failed to change state, switching children back to %s",
2845 gst_element_state_get_name (current));
2848 gst_iterator_foreach (it, &reset_state, GINT_TO_POINTER (current));
2849 } while (ret == GST_ITERATOR_RESYNC);
2850 gst_iterator_free (it);
2857 * This function is a utility event handler for seek events.
2858 * It will send the event to all sinks or sources and appropriate
2859 * ghost pads depending on the event-direction.
2861 * Applications are free to override this behaviour and
2862 * implement their own seek handler, but this will work for
2863 * pretty much all cases in practice.
2866 gst_bin_send_event (GstElement * element, GstEvent * event)
2868 GstBin *bin = GST_BIN_CAST (element);
2870 gboolean res = TRUE;
2871 gboolean done = FALSE;
2872 GValue data = { 0, };
2874 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2875 iter = gst_bin_iterate_sources (bin);
2876 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
2877 GST_EVENT_TYPE_NAME (event));
2879 iter = gst_bin_iterate_sinks (bin);
2880 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
2881 GST_EVENT_TYPE_NAME (event));
2885 switch (gst_iterator_next (iter, &data)) {
2886 case GST_ITERATOR_OK:
2888 GstElement *child = g_value_get_object (&data);
2890 gst_event_ref (event);
2891 res &= gst_element_send_event (child, event);
2893 GST_LOG_OBJECT (child, "After handling %s event: %d",
2894 GST_EVENT_TYPE_NAME (event), res);
2896 g_value_reset (&data);
2899 case GST_ITERATOR_RESYNC:
2900 gst_iterator_resync (iter);
2903 case GST_ITERATOR_DONE:
2906 case GST_ITERATOR_ERROR:
2907 g_assert_not_reached ();
2911 g_value_unset (&data);
2912 gst_iterator_free (iter);
2914 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2915 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
2916 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
2917 GST_EVENT_TYPE_NAME (event));
2919 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
2920 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
2921 GST_EVENT_TYPE_NAME (event));
2926 switch (gst_iterator_next (iter, &data)) {
2927 case GST_ITERATOR_OK:
2929 GstPad *pad = g_value_get_object (&data);
2931 gst_event_ref (event);
2932 res &= gst_pad_send_event (pad, event);
2933 GST_LOG_OBJECT (pad, "After handling %s event: %d",
2934 GST_EVENT_TYPE_NAME (event), res);
2937 case GST_ITERATOR_RESYNC:
2938 gst_iterator_resync (iter);
2941 case GST_ITERATOR_DONE:
2944 case GST_ITERATOR_ERROR:
2945 g_assert_not_reached ();
2950 g_value_unset (&data);
2951 gst_iterator_free (iter);
2952 gst_event_unref (event);
2957 /* this is the function called by the threadpool. When async elements commit
2958 * their state, this function will attempt to bring the bin to the next state.
2961 gst_bin_continue_func (BinContinueData * data)
2964 GstState current, next, pending;
2965 GstStateChange transition;
2968 pending = data->pending;
2970 GST_DEBUG_OBJECT (bin, "waiting for state lock");
2971 GST_STATE_LOCK (bin);
2973 GST_DEBUG_OBJECT (bin, "doing state continue");
2974 GST_OBJECT_LOCK (bin);
2976 /* if a new state change happened after this thread was scheduled, we return
2978 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
2981 current = GST_STATE (bin);
2982 next = GST_STATE_GET_NEXT (current, pending);
2983 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
2985 GST_STATE_NEXT (bin) = next;
2986 GST_STATE_PENDING (bin) = pending;
2988 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
2989 GST_OBJECT_UNLOCK (bin);
2991 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
2992 "continue state change %s to %s, final %s",
2993 gst_element_state_get_name (current),
2994 gst_element_state_get_name (next), gst_element_state_get_name (pending));
2996 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
2998 GST_STATE_UNLOCK (bin);
2999 GST_DEBUG_OBJECT (bin, "state continue done");
3001 gst_object_unref (bin);
3002 g_slice_free (BinContinueData, data);
3007 GST_OBJECT_UNLOCK (bin);
3008 GST_STATE_UNLOCK (bin);
3009 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
3010 gst_object_unref (bin);
3011 g_slice_free (BinContinueData, data);
3016 static GstBusSyncReply
3017 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
3019 GstBinClass *bclass;
3021 bclass = GST_BIN_GET_CLASS (bin);
3022 if (bclass->handle_message)
3023 bclass->handle_message (bin, message);
3025 gst_message_unref (message);
3027 return GST_BUS_DROP;
3031 bin_push_state_continue (BinContinueData * data)
3038 klass = GST_BIN_GET_CLASS (bin);
3040 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
3041 g_thread_pool_push (klass->pool, data, NULL);
3044 /* an element started an async state change, if we were not busy with a state
3045 * change, we perform a lost state.
3046 * This function is called with the OBJECT lock.
3049 bin_handle_async_start (GstBin * bin)
3051 GstState old_state, new_state;
3053 GstMessage *amessage = NULL;
3055 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3058 /* get our toplevel state */
3059 toplevel = BIN_IS_TOPLEVEL (bin);
3061 /* prepare an ASYNC_START message, we always post the start message even if we
3062 * are busy with a state change or when we are NO_PREROLL. */
3064 /* non toplevel bin, prepare async-start for the parent */
3065 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
3067 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
3070 /* async starts are ignored when we are NO_PREROLL */
3071 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
3072 goto was_no_preroll;
3074 old_state = GST_STATE (bin);
3076 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
3077 * PLAYING after optionally redistributing the base_time. */
3078 if (old_state > GST_STATE_PAUSED)
3079 new_state = GST_STATE_PAUSED;
3081 new_state = old_state;
3083 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3084 "lost state of %s, new %s", gst_element_state_get_name (old_state),
3085 gst_element_state_get_name (new_state));
3087 GST_STATE (bin) = new_state;
3088 GST_STATE_NEXT (bin) = new_state;
3089 GST_STATE_PENDING (bin) = new_state;
3090 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3091 GST_OBJECT_UNLOCK (bin);
3094 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
3099 /* post our ASYNC_START. */
3100 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
3101 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3103 GST_OBJECT_LOCK (bin);
3109 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3114 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3115 GST_OBJECT_UNLOCK (bin);
3120 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3121 GST_OBJECT_UNLOCK (bin);
3126 /* this function is called when there are no more async elements in the bin. We
3127 * post a state changed message and an ASYNC_DONE message.
3128 * This function is called with the OBJECT lock.
3131 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3132 gboolean flag_pending, GstClockTime running_time)
3134 GstState current, pending, target;
3135 GstStateChangeReturn old_ret;
3136 GstState old_state, old_next;
3137 gboolean toplevel, state_changed = FALSE;
3138 GstMessage *amessage = NULL;
3139 BinContinueData *cont = NULL;
3141 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3144 pending = GST_STATE_PENDING (bin);
3149 /* check if there is something to commit */
3150 if (pending == GST_STATE_VOID_PENDING)
3151 goto nothing_pending;
3153 old_ret = GST_STATE_RETURN (bin);
3154 GST_STATE_RETURN (bin) = ret;
3156 /* move to the next target state */
3157 target = GST_STATE_TARGET (bin);
3158 pending = GST_STATE_PENDING (bin) = target;
3160 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3162 old_state = GST_STATE (bin);
3163 /* this is the state we should go to next */
3164 old_next = GST_STATE_NEXT (bin);
3166 if (old_next != GST_STATE_PLAYING) {
3167 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3168 "committing state from %s to %s, old pending %s",
3169 gst_element_state_get_name (old_state),
3170 gst_element_state_get_name (old_next),
3171 gst_element_state_get_name (pending));
3173 /* update current state */
3174 current = GST_STATE (bin) = old_next;
3176 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3177 "setting state from %s to %s, pending %s",
3178 gst_element_state_get_name (old_state),
3179 gst_element_state_get_name (old_state),
3180 gst_element_state_get_name (pending));
3181 current = old_state;
3184 /* get our toplevel state */
3185 toplevel = BIN_IS_TOPLEVEL (bin);
3187 /* see if we reached the final state. If we are not toplevel, we also have to
3188 * stop here, the parent will continue our state. */
3189 if ((pending == current) || !toplevel) {
3190 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3191 "completed state change, pending VOID");
3193 /* mark VOID pending */
3194 pending = GST_STATE_VOID_PENDING;
3195 GST_STATE_PENDING (bin) = pending;
3196 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3198 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3199 "continue state change, pending %s",
3200 gst_element_state_get_name (pending));
3202 cont = g_slice_new (BinContinueData);
3204 /* ref to the bin */
3205 cont->bin = gst_object_ref (bin);
3206 /* cookie to detect concurrent state change */
3207 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3208 /* pending target state */
3209 cont->pending = pending;
3211 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3212 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3215 if (old_next != GST_STATE_PLAYING) {
3216 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3217 state_changed = TRUE;
3220 GST_OBJECT_UNLOCK (bin);
3222 if (state_changed) {
3223 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3227 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3228 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3229 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3232 GST_OBJECT_LOCK (bin);
3234 /* toplevel, start continue state */
3235 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3236 bin_push_state_continue (cont);
3238 GST_DEBUG_OBJECT (bin, "state change complete");
3239 GST_STATE_BROADCAST (bin);
3245 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3250 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3251 /* if we were busy with a state change and we are requested to flag a
3252 * pending async done, we do so here */
3254 bin->priv->pending_async_done = TRUE;
3259 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3265 bin_do_eos (GstBin * bin)
3270 GST_OBJECT_LOCK (bin);
3271 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3272 * we forward the EOS message to the parent bin or application
3274 eos = GST_STATE (bin) == GST_STATE_PLAYING
3275 && GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING
3276 && bin->priv->posted_playing && is_eos (bin, &seqnum);
3277 GST_OBJECT_UNLOCK (bin);
3280 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3282 GstMessage *tmessage;
3284 /* Clear out any further messages, and reset posted_eos so we can
3285 detect any new EOS that happens (eg, after a seek). Since all
3286 sinks have now posted an EOS, there will be no further EOS events
3287 seen unless there is a new logical EOS */
3288 GST_OBJECT_LOCK (bin);
3289 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3290 bin->priv->posted_eos = FALSE;
3291 GST_OBJECT_UNLOCK (bin);
3293 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3294 gst_message_set_seqnum (tmessage, seqnum);
3295 GST_DEBUG_OBJECT (bin,
3296 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3297 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3302 bin_do_stream_start (GstBin * bin)
3305 gboolean stream_start;
3306 gboolean have_group_id = FALSE;
3309 GST_OBJECT_LOCK (bin);
3310 /* If all sinks are STREAM_START we forward the STREAM_START message
3311 * to the parent bin or application
3313 stream_start = is_stream_start (bin, &seqnum, &have_group_id, &group_id);
3314 GST_OBJECT_UNLOCK (bin);
3317 GstMessage *tmessage;
3319 GST_OBJECT_LOCK (bin);
3320 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3321 GST_OBJECT_UNLOCK (bin);
3323 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3324 gst_message_set_seqnum (tmessage, seqnum);
3326 gst_message_set_group_id (tmessage, group_id);
3328 GST_DEBUG_OBJECT (bin,
3329 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3331 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3335 /* must be called without the object lock as it posts messages */
3337 bin_do_message_forward (GstBin * bin, GstMessage * message)
3339 if (bin->priv->message_forward) {
3340 GstMessage *forwarded;
3342 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3343 GST_MESSAGE_TYPE_NAME (message));
3345 /* we need to convert these messages to element messages so that our parent
3346 * bin can easily ignore them and so that the application can easily
3347 * distinguish between the internally forwarded and the real messages. */
3348 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3349 gst_structure_new ("GstBinForwarded",
3350 "message", GST_TYPE_MESSAGE, message, NULL));
3352 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3357 gst_bin_update_context (GstBin * bin, GstContext * context)
3360 const gchar *context_type;
3362 GST_OBJECT_LOCK (bin);
3363 context_type = gst_context_get_context_type (context);
3364 for (l = bin->priv->contexts; l; l = l->next) {
3365 GstContext *tmp = l->data;
3366 const gchar *tmp_type = gst_context_get_context_type (tmp);
3368 /* Always store newest context but never replace
3369 * a persistent one by a non-persistent one */
3370 if (strcmp (context_type, tmp_type) == 0 &&
3371 (gst_context_is_persistent (context) ||
3372 !gst_context_is_persistent (tmp))) {
3373 gst_context_replace ((GstContext **) & l->data, context);
3377 /* Not found? Add */
3379 bin->priv->contexts =
3380 g_list_prepend (bin->priv->contexts, gst_context_ref (context));
3381 GST_OBJECT_UNLOCK (bin);
3384 /* handle child messages:
3386 * This method is called synchronously when a child posts a message on
3389 * GST_MESSAGE_EOS: This message is only posted by sinks
3390 * in the PLAYING state. If all sinks posted the EOS message, post
3393 * GST_MESSAGE_STATE_DIRTY: Deprecated
3395 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3396 * element posts segment_start twice, only the last message is kept.
3398 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3399 * with the segment_done message. If there are no more segment_start
3400 * messages, post segment_done message upwards.
3402 * GST_MESSAGE_DURATION_CHANGED: clear any cached durations.
3403 * Whenever someone performs a duration query on the bin, we store the
3404 * result so we can answer it quicker the next time. Any element that
3405 * changes its duration marks our cached values invalid.
3406 * This message is also posted upwards. This is currently disabled
3407 * because too many elements don't post DURATION_CHANGED messages when
3408 * the duration changes.
3410 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3411 * can no longer provide a clock. The default bin behaviour is to
3412 * check if the lost clock was the one provided by the bin. If so and
3413 * we are currently in the PLAYING state, we forward the message to
3415 * This message is also generated when we remove a clock provider from
3416 * a bin. If this message is received by the application, it should
3417 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3418 * and a new base_time distribution.
3420 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3421 * can provide a clock. This mostly happens when we add a new clock
3422 * provider to the bin. The default behaviour of the bin is to mark the
3423 * currently selected clock as dirty, which will perform a clock
3424 * recalculation the next time we are asked to provide a clock.
3425 * This message is never sent to the application but is forwarded to
3428 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3429 * the state of the element and the fact that the element will need a
3430 * new base_time. This message is not forwarded to the application.
3432 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3433 * element when it posted ASYNC_START. If all elements are done, post a
3434 * ASYNC_DONE message to the parent.
3436 * OTHER: post upwards.
3439 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3442 GstMessageType type;
3443 GstMessage *tmessage;
3446 src = GST_MESSAGE_SRC (message);
3447 type = GST_MESSAGE_TYPE (message);
3449 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3450 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3451 GST_MESSAGE_TYPE_NAME (message));
3454 case GST_MESSAGE_ERROR:
3456 GST_OBJECT_LOCK (bin);
3458 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3459 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3460 GST_STATE_BROADCAST (bin);
3461 GST_OBJECT_UNLOCK (bin);
3465 case GST_MESSAGE_EOS:
3468 /* collect all eos messages from the children */
3469 bin_do_message_forward (bin, message);
3470 GST_OBJECT_LOCK (bin);
3471 /* ref message for future use */
3472 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3473 GST_OBJECT_UNLOCK (bin);
3478 case GST_MESSAGE_STREAM_START:
3481 /* collect all stream_start messages from the children */
3482 GST_OBJECT_LOCK (bin);
3483 /* ref message for future use */
3484 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3485 GST_OBJECT_UNLOCK (bin);
3487 bin_do_stream_start (bin);
3490 case GST_MESSAGE_STATE_DIRTY:
3492 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3495 gst_message_unref (message);
3498 case GST_MESSAGE_SEGMENT_START:{
3499 gboolean post = FALSE;
3503 gst_message_parse_segment_start (message, &format, &position);
3504 seqnum = gst_message_get_seqnum (message);
3506 bin_do_message_forward (bin, message);
3508 GST_OBJECT_LOCK (bin);
3509 /* if this is the first segment-start, post to parent but not to the
3511 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3512 (GST_OBJECT_PARENT (bin) != NULL)) {
3515 /* replace any previous segment_start message from this source
3516 * with the new segment start message */
3517 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3518 GST_OBJECT_UNLOCK (bin);
3520 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3522 gst_message_set_seqnum (tmessage, seqnum);
3524 /* post segment start with initial format and position. */
3525 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3527 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3531 case GST_MESSAGE_SEGMENT_DONE:
3533 gboolean post = FALSE;
3537 gst_message_parse_segment_done (message, &format, &position);
3538 seqnum = gst_message_get_seqnum (message);
3540 bin_do_message_forward (bin, message);
3542 GST_OBJECT_LOCK (bin);
3543 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3544 /* if there are no more segment_start messages, everybody posted
3545 * a segment_done and we can post one on the bus. */
3547 /* we don't care who still has a pending segment start */
3548 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3551 /* remove all old segment_done messages */
3552 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3554 GST_OBJECT_UNLOCK (bin);
3556 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3558 gst_message_set_seqnum (tmessage, seqnum);
3560 /* post segment done with latest format and position. */
3561 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3563 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3567 case GST_MESSAGE_DURATION_CHANGED:
3569 /* FIXME: remove all cached durations, next time somebody asks
3570 * for duration, we will recalculate. */
3572 GST_OBJECT_LOCK (bin);
3573 bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION_CHANGED);
3574 GST_OBJECT_UNLOCK (bin);
3578 case GST_MESSAGE_CLOCK_LOST:
3580 GstClock **provided_clock_p;
3581 GstElement **clock_provider_p;
3582 gboolean playing, toplevel, provided, forward;
3585 gst_message_parse_clock_lost (message, &clock);
3587 GST_OBJECT_LOCK (bin);
3588 bin->clock_dirty = TRUE;
3589 /* if we lost the clock that we provided, post to parent but
3590 * only if we are not a top-level bin or PLAYING.
3591 * The reason for this is that applications should be able
3592 * to PAUSE/PLAY if they receive this message without worrying
3593 * about the state of the pipeline. */
3594 provided = (clock == bin->provided_clock);
3595 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3596 toplevel = GST_OBJECT_PARENT (bin) == NULL;
3597 forward = provided && (playing || !toplevel);
3599 GST_DEBUG_OBJECT (bin,
3600 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3601 bin->provided_clock, bin->clock_provider);
3602 provided_clock_p = &bin->provided_clock;
3603 clock_provider_p = &bin->clock_provider;
3604 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3605 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3607 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3608 provided, playing, forward);
3609 GST_OBJECT_UNLOCK (bin);
3615 gst_message_unref (message);
3618 case GST_MESSAGE_CLOCK_PROVIDE:
3622 GST_OBJECT_LOCK (bin);
3623 bin->clock_dirty = TRUE;
3624 /* a new clock is available, post to parent but not
3625 * to the application */
3626 forward = GST_OBJECT_PARENT (bin) != NULL;
3627 GST_OBJECT_UNLOCK (bin);
3633 gst_message_unref (message);
3636 case GST_MESSAGE_ASYNC_START:
3640 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3641 src ? GST_OBJECT_NAME (src) : "(NULL)");
3643 bin_do_message_forward (bin, message);
3645 GST_OBJECT_LOCK (bin);
3646 /* we ignore the message if we are going to <= READY */
3647 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3648 goto ignore_start_message;
3650 /* takes ownership of the message */
3651 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3653 bin_handle_async_start (bin);
3654 GST_OBJECT_UNLOCK (bin);
3657 ignore_start_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_ASYNC_DONE:
3668 GstClockTime running_time;
3671 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3672 src ? GST_OBJECT_NAME (src) : "(NULL)");
3674 gst_message_parse_async_done (message, &running_time);
3676 bin_do_message_forward (bin, message);
3678 GST_OBJECT_LOCK (bin);
3679 /* ignore messages if we are shutting down */
3680 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3681 goto ignore_done_message;
3683 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3684 /* if there are no more ASYNC_START messages, everybody posted
3685 * a ASYNC_DONE and we can post one on the bus. When checking, we
3686 * don't care who still has a pending ASYNC_START */
3687 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3688 /* nothing found, remove all old ASYNC_DONE messages */
3689 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3691 GST_DEBUG_OBJECT (bin, "async elements commited");
3692 /* when we get an async done message when a state change was busy, we
3693 * need to set the pending_done flag so that at the end of the state
3694 * change we can see if we need to verify pending async elements, hence
3695 * the TRUE argument here. */
3696 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3699 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3701 GST_OBJECT_UNLOCK (bin);
3704 ignore_done_message:
3706 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3707 gst_element_state_get_name (target));
3708 GST_OBJECT_UNLOCK (bin);
3709 gst_message_unref (message);
3713 case GST_MESSAGE_STRUCTURE_CHANGE:
3717 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3719 GST_OBJECT_LOCK (bin);
3721 /* while the pad is busy, avoid following it when doing state changes.
3722 * Don't update the cookie yet, we will do that after the structure
3723 * change finished and we are ready to inspect the new updated
3725 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3728 /* a pad link/unlink ended, signal the state change iterator that we
3729 * need to resync by updating the structure_cookie. */
3730 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3731 GST_MESSAGE_STRUCTURE_CHANGE);
3732 if (!GST_BIN_IS_NO_RESYNC (bin))
3733 bin->priv->structure_cookie++;
3735 GST_OBJECT_UNLOCK (bin);
3738 gst_message_unref (message);
3742 case GST_MESSAGE_NEED_CONTEXT:{
3743 const gchar *context_type;
3746 gst_message_parse_context_type (message, &context_type);
3747 GST_OBJECT_LOCK (bin);
3748 for (l = bin->priv->contexts; l; l = l->next) {
3749 GstContext *tmp = l->data;
3750 const gchar *tmp_type = gst_context_get_context_type (tmp);
3752 if (strcmp (context_type, tmp_type) == 0) {
3753 gst_element_set_context (GST_ELEMENT (src), l->data);
3757 GST_OBJECT_UNLOCK (bin);
3759 /* Forward if we couldn't answer the message */
3763 gst_message_unref (message);
3768 case GST_MESSAGE_HAVE_CONTEXT:{
3769 GstContext *context;
3771 gst_message_parse_have_context (message, &context);
3772 gst_bin_update_context (bin, context);
3773 gst_context_unref (context);
3785 /* Send all other messages upward */
3786 GST_DEBUG_OBJECT (bin, "posting message upward");
3787 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
3792 /* generic struct passed to all query fold methods */
3801 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
3802 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
3804 /* for duration/position we collect all durations/positions and take
3805 * the MAX of all valid results */
3807 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
3815 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3817 gboolean res = FALSE;
3818 GstObject *item = g_value_get_object (vitem);
3819 if (GST_IS_PAD (item))
3820 res = gst_pad_query (GST_PAD (item), fold->query);
3822 res = gst_element_query (GST_ELEMENT (item), fold->query);
3827 g_value_set_boolean (ret, TRUE);
3829 gst_query_parse_duration (fold->query, NULL, &duration);
3831 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
3833 if (duration == -1) {
3834 /* duration query succeeded, but duration is unknown */
3839 if (duration > fold->max)
3840 fold->max = duration;
3847 bin_query_duration_done (GstBin * bin, QueryFold * fold)
3851 gst_query_parse_duration (fold->query, &format, NULL);
3852 /* store max in query result */
3853 gst_query_set_duration (fold->query, format, fold->max);
3855 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
3857 /* FIXME: re-implement duration caching */
3860 GST_OBJECT_LOCK (bin);
3861 bin->messages = g_list_prepend (bin->messages,
3862 gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
3863 GST_OBJECT_UNLOCK (bin);
3868 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3870 gboolean res = FALSE;
3871 GstObject *item = g_value_get_object (vitem);
3872 if (GST_IS_PAD (item))
3873 res = gst_pad_query (GST_PAD (item), fold->query);
3875 res = gst_element_query (GST_ELEMENT (item), fold->query);
3880 g_value_set_boolean (ret, TRUE);
3882 gst_query_parse_position (fold->query, NULL, &position);
3884 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
3886 if (position > fold->max)
3887 fold->max = position;
3894 bin_query_position_done (GstBin * bin, QueryFold * fold)
3898 gst_query_parse_position (fold->query, &format, NULL);
3899 /* store max in query result */
3900 gst_query_set_position (fold->query, format, fold->max);
3902 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
3906 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3908 gboolean res = FALSE;
3909 GstObject *item = g_value_get_object (vitem);
3910 if (GST_IS_PAD (item))
3911 res = gst_pad_query (GST_PAD (item), fold->query);
3913 res = gst_element_query (GST_ELEMENT (item), fold->query);
3915 GstClockTime min, max;
3918 gst_query_parse_latency (fold->query, &live, &min, &max);
3920 GST_DEBUG_OBJECT (item,
3921 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3922 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
3924 /* for the combined latency we collect the MAX of all min latencies and
3925 * the MIN of all max latencies */
3927 if (min > fold->min)
3929 if (fold->max == -1)
3931 else if (max < fold->max)
3937 g_value_set_boolean (ret, FALSE);
3938 GST_DEBUG_OBJECT (item, "failed query");
3945 bin_query_latency_done (GstBin * bin, QueryFold * fold)
3947 /* store max in query result */
3948 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
3950 GST_DEBUG_OBJECT (bin,
3951 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3952 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
3956 /* generic fold, return first valid result */
3958 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3960 gboolean res = FALSE;
3961 GstObject *item = g_value_get_object (vitem);
3962 if (GST_IS_PAD (item))
3963 res = gst_pad_query (GST_PAD (item), fold->query);
3965 res = gst_element_query (GST_ELEMENT (item), fold->query);
3967 g_value_set_boolean (ret, TRUE);
3968 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
3971 /* and stop as soon as we have a valid result */
3975 /* Perform a query iteration for the given bin. The query is stored in
3976 * QueryFold and iter should be either a GstPad iterator or a
3977 * GstElement iterator. */
3979 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
3980 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
3981 QueryFold * fold_data, gboolean default_return)
3983 gboolean res = default_return;
3985 /* set the result of the query to FALSE initially */
3986 g_value_init (&ret, G_TYPE_BOOLEAN);
3987 g_value_set_boolean (&ret, res);
3990 GstIteratorResult ires;
3992 ires = gst_iterator_fold (iter, fold_func, &ret, fold_data);
3995 case GST_ITERATOR_RESYNC:
3996 gst_iterator_resync (iter);
3998 fold_init (bin, fold_data);
3999 g_value_set_boolean (&ret, res);
4001 case GST_ITERATOR_OK:
4002 case GST_ITERATOR_DONE:
4003 res = g_value_get_boolean (&ret);
4004 if (fold_done != NULL && res)
4005 fold_done (bin, fold_data);
4017 gst_bin_query (GstElement * element, GstQuery * query)
4019 GstBin *bin = GST_BIN_CAST (element);
4021 gboolean default_return = FALSE;
4022 gboolean res = FALSE;
4023 gboolean src_pads_query_result = FALSE;
4024 GstIteratorFoldFunction fold_func;
4025 QueryInitFunction fold_init = NULL;
4026 QueryDoneFunction fold_done = NULL;
4027 QueryFold fold_data;
4029 switch (GST_QUERY_TYPE (query)) {
4030 case GST_QUERY_DURATION:
4032 /* FIXME: implement duration caching in GstBin again */
4037 gst_query_parse_duration (query, &qformat, NULL);
4039 /* find cached duration query */
4040 GST_OBJECT_LOCK (bin);
4041 for (cached = bin->messages; cached; cached = g_list_next (cached)) {
4042 GstMessage *message = (GstMessage *) cached->data;
4044 if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION_CHANGED &&
4045 GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
4049 gst_message_parse_duration (message, &format, &duration);
4051 /* if cached same format, copy duration in query result */
4052 if (format == qformat) {
4053 GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
4055 GST_OBJECT_UNLOCK (bin);
4057 gst_query_set_duration (query, qformat, duration);
4063 GST_OBJECT_UNLOCK (bin);
4065 GST_FIXME ("implement duration caching in GstBin again");
4067 /* no cached value found, iterate and collect durations */
4068 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
4069 fold_init = bin_query_min_max_init;
4070 fold_done = bin_query_duration_done;
4073 case GST_QUERY_POSITION:
4075 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
4076 fold_init = bin_query_min_max_init;
4077 fold_done = bin_query_position_done;
4080 case GST_QUERY_LATENCY:
4082 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
4083 fold_init = bin_query_min_max_init;
4084 fold_done = bin_query_latency_done;
4085 default_return = TRUE;
4089 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
4093 fold_data.query = query;
4095 iter = gst_bin_iterate_sinks (bin);
4096 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
4097 query, GST_QUERY_TYPE_NAME (query));
4100 fold_init (bin, &fold_data);
4103 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, &fold_data,
4105 gst_iterator_free (iter);
4108 /* Query the source pads of the element */
4109 iter = gst_element_iterate_src_pads (element);
4110 src_pads_query_result =
4111 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
4112 &fold_data, default_return);
4113 gst_iterator_free (iter);
4115 if (src_pads_query_result)
4119 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
4125 set_context (const GValue * item, gpointer user_data)
4127 GstElement *element = g_value_get_object (item);
4129 gst_element_set_context (element, user_data);
4133 gst_bin_set_context (GstElement * element, GstContext * context)
4136 GstIterator *children;
4138 g_return_if_fail (GST_IS_BIN (element));
4140 bin = GST_BIN (element);
4142 gst_bin_update_context (bin, context);
4144 children = gst_bin_iterate_elements (bin);
4145 while (gst_iterator_foreach (children, set_context,
4146 context) == GST_ITERATOR_RESYNC)
4147 gst_iterator_resync (children);
4148 gst_iterator_free (children);
4152 compare_name (const GValue * velement, const gchar * name)
4155 GstElement *element = g_value_get_object (velement);
4157 GST_OBJECT_LOCK (element);
4158 eq = strcmp (GST_ELEMENT_NAME (element), name);
4159 GST_OBJECT_UNLOCK (element);
4165 * gst_bin_get_by_name:
4167 * @name: the element name to search for
4169 * Gets the element with the given name from a bin. This
4170 * function recurses into child bins.
4172 * Returns %NULL if no element with the given name is found in the bin.
4174 * MT safe. Caller owns returned reference.
4176 * Returns: (transfer full) (nullable): the #GstElement with the given
4180 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4182 GstIterator *children;
4183 GValue result = { 0, };
4184 GstElement *element;
4187 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4189 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4190 GST_ELEMENT_NAME (bin), name);
4192 children = gst_bin_iterate_recurse (bin);
4193 found = gst_iterator_find_custom (children,
4194 (GCompareFunc) compare_name, &result, (gpointer) name);
4195 gst_iterator_free (children);
4198 element = g_value_dup_object (&result);
4199 g_value_unset (&result);
4208 * gst_bin_get_by_name_recurse_up:
4210 * @name: the element name to search for
4212 * Gets the element with the given name from this bin. If the
4213 * element is not found, a recursion is performed on the parent bin.
4216 * - no element with the given name is found in the bin
4218 * MT safe. Caller owns returned reference.
4220 * Returns: (transfer full) (nullable): the #GstElement with the given
4224 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4228 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4229 g_return_val_if_fail (name != NULL, NULL);
4231 result = gst_bin_get_by_name (bin, name);
4236 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4238 if (GST_IS_BIN (parent)) {
4239 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4241 gst_object_unref (parent);
4249 compare_interface (const GValue * velement, GValue * interface)
4251 GstElement *element = g_value_get_object (velement);
4252 GType interface_type = (GType) g_value_get_pointer (interface);
4255 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4264 * gst_bin_get_by_interface:
4266 * @iface: the #GType of an interface
4268 * Looks for an element inside the bin that implements the given
4269 * interface. If such an element is found, it returns the element.
4270 * You can cast this element to the given interface afterwards. If you want
4271 * all elements that implement the interface, use
4272 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4274 * MT safe. Caller owns returned reference.
4276 * Returns: (transfer full): A #GstElement inside the bin implementing the interface
4279 gst_bin_get_by_interface (GstBin * bin, GType iface)
4281 GstIterator *children;
4282 GValue result = { 0, };
4283 GstElement *element;
4285 GValue viface = { 0, };
4287 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4288 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4290 g_value_init (&viface, G_TYPE_POINTER);
4291 g_value_set_pointer (&viface, (gpointer) iface);
4293 children = gst_bin_iterate_recurse (bin);
4294 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4296 gst_iterator_free (children);
4299 element = g_value_dup_object (&result);
4300 g_value_unset (&result);
4304 g_value_unset (&viface);
4310 * gst_bin_iterate_all_by_interface:
4312 * @iface: the #GType of an interface
4314 * Looks for all elements inside the bin that implements the given
4315 * interface. You can safely cast all returned elements to the given interface.
4316 * The function recurses inside child bins. The iterator will yield a series
4317 * of #GstElement that should be unreffed after use.
4319 * MT safe. Caller owns returned value.
4321 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
4322 * for all elements in the bin implementing the given interface,
4326 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4328 GstIterator *children;
4329 GstIterator *result;
4330 GValue viface = { 0, };
4332 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4333 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4335 g_value_init (&viface, G_TYPE_POINTER);
4336 g_value_set_pointer (&viface, (gpointer) iface);
4338 children = gst_bin_iterate_recurse (bin);
4339 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4342 g_value_unset (&viface);