3 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
4 * 2004 Wim Taymans <wim.taymans@gmail.com>
6 * gstbin.c: GstBin container object and support code
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
28 * @short_description: Base class and element that can contain other elements
30 * #GstBin is an element that can contain other #GstElement, allowing them to be
32 * Pads from the child elements can be ghosted to the bin, see #GstGhostPad.
33 * This makes the bin look like any other elements and enables creation of
34 * higher-level abstraction elements.
36 * A new #GstBin is created with gst_bin_new(). Use a #GstPipeline instead if you
37 * want to create a toplevel bin because a normal bin doesn't have a bus or
38 * handle clock distribution of its own.
40 * After the bin has been created you will typically add elements to it with
41 * gst_bin_add(). You can remove elements with gst_bin_remove().
43 * An element can be retrieved from a bin with gst_bin_get_by_name(), using the
44 * elements name. gst_bin_get_by_name_recurse_up() is mainly used for internal
45 * purposes and will query the parent bins when the element is not found in the
48 * An iterator of elements in a bin can be retrieved with
49 * gst_bin_iterate_elements(). Various other iterators exist to retrieve the
52 * gst_object_unref() is used to drop your reference to the bin.
54 * The #GstBin::element-added signal is fired whenever a new element is added to
55 * the bin. Likewise the #GstBin::element-removed signal is fired whenever an
56 * element is removed from the bin.
58 * <refsect2><title>Notes</title>
60 * A #GstBin internally intercepts every #GstMessage posted by its children and
61 * implements the following default behaviour for each of them:
64 * <term>GST_MESSAGE_EOS</term>
65 * <listitem><para>This message is only posted by sinks in the PLAYING
66 * state. If all sinks posted the EOS message, this bin will post and EOS
67 * message upwards.</para></listitem>
70 * <term>GST_MESSAGE_SEGMENT_START</term>
71 * <listitem><para>just collected and never forwarded upwards.
72 * The messages are used to decide when all elements have completed playback
73 * of their segment.</para></listitem>
76 * <term>GST_MESSAGE_SEGMENT_DONE</term>
77 * <listitem><para> Is posted by #GstBin when all elements that posted
78 * a SEGMENT_START have posted a SEGMENT_DONE.</para></listitem>
81 * <term>GST_MESSAGE_DURATION_CHANGED</term>
82 * <listitem><para> Is posted by an element that detected a change
83 * in the stream duration. The default bin behaviour is to clear any
84 * cached duration values so that the next duration query will perform
85 * a full duration recalculation. The duration change is posted to the
86 * application so that it can refetch the new duration with a duration
87 * query. Note that these messages can be posted before the bin is
88 * prerolled, in which case the duration query might fail.
92 * <term>GST_MESSAGE_CLOCK_LOST</term>
93 * <listitem><para> This message is posted by an element when it
94 * can no longer provide a clock. The default bin behaviour is to
95 * check if the lost clock was the one provided by the bin. If so and
96 * the bin is currently in the PLAYING state, the message is forwarded to
98 * This message is also generated when a clock provider is removed from
99 * the bin. If this message is received by the application, it should
100 * PAUSE the pipeline and set it back to PLAYING to force a new clock
105 * <term>GST_MESSAGE_CLOCK_PROVIDE</term>
106 * <listitem><para> This message is generated when an element
107 * can provide a clock. This mostly happens when a new clock
108 * provider is added to the bin. The default behaviour of the bin is to
109 * mark the currently selected clock as dirty, which will perform a clock
110 * recalculation the next time the bin is asked to provide a clock.
111 * This message is never sent tot the application but is forwarded to
112 * the parent of the bin.
116 * <term>OTHERS</term>
117 * <listitem><para> posted upwards.</para></listitem>
122 * A #GstBin implements the following default behaviour for answering to a
126 * <term>GST_QUERY_DURATION</term>
127 * <listitem><para>If the query has been asked before with the same format
128 * and the bin is a toplevel bin (ie. has no parent),
129 * use the cached previous value. If no previous value was cached, the
130 * query is sent to all sink elements in the bin and the MAXIMUM of all
131 * values is returned. If the bin is a toplevel bin the value is cached.
132 * If no sinks are available in the bin, the query fails.
136 * <term>GST_QUERY_POSITION</term>
137 * <listitem><para>The query is sent to all sink elements in the bin and the
138 * MAXIMUM of all values is returned. If no sinks are available in the bin,
143 * <term>OTHERS</term>
144 * <listitem><para>the query is forwarded to all sink elements, the result
145 * of the first sink that answers the query successfully is returned. If no
146 * sink is in the bin, the query fails.</para></listitem>
150 * A #GstBin will by default forward any event sent to it to all sink elements.
151 * If all the sinks return TRUE, the bin will also return TRUE, else FALSE is
152 * returned. If no sinks are in the bin, the event handler will return TRUE.
157 * Last reviewed on 2012-03-28 (0.11.3)
160 #include "gst_private.h"
162 #include "gstevent.h"
165 #include "gsterror.h"
167 #include "gstutils.h"
168 #include "gstchildproxy.h"
170 GST_DEBUG_CATEGORY_STATIC (bin_debug);
171 #define GST_CAT_DEFAULT bin_debug
173 /* a bin is toplevel if it has no parent or when it is configured to behave like
175 #define BIN_IS_TOPLEVEL(bin) ((GST_OBJECT_PARENT (bin) == NULL) || bin->priv->asynchandling)
177 #define GST_BIN_GET_PRIVATE(obj) \
178 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BIN, GstBinPrivate))
180 struct _GstBinPrivate
182 gboolean asynchandling;
183 /* if we get an ASYNC_DONE message from ourselves, this means that the
184 * subclass will simulate ASYNC behaviour without having ASYNC children. When
185 * such an ASYNC_DONE message is posted while we are doing a state change, we
186 * have to process the message after finishing the state change even when no
187 * child returned GST_STATE_CHANGE_ASYNC. */
188 gboolean pending_async_done;
190 guint32 structure_cookie;
199 /* forward messages from our children */
200 gboolean message_forward;
212 static void gst_bin_dispose (GObject * object);
214 static void gst_bin_set_property (GObject * object, guint prop_id,
215 const GValue * value, GParamSpec * pspec);
216 static void gst_bin_get_property (GObject * object, guint prop_id,
217 GValue * value, GParamSpec * pspec);
219 static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
220 GstStateChange transition);
221 static void gst_bin_state_changed (GstElement * element, GstState oldstate,
222 GstState newstate, GstState pending);
223 static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
224 GstState * state, GstState * pending, GstClockTime timeout);
225 static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
226 gboolean flag_pending, GstClockTime running_time);
227 static void bin_handle_async_start (GstBin * bin);
228 static void bin_push_state_continue (BinContinueData * data);
229 static void bin_do_eos (GstBin * bin);
231 static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
232 static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
235 static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
236 static GstIndex *gst_bin_get_index_func (GstElement * element);
239 static GstClock *gst_bin_provide_clock_func (GstElement * element);
240 static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
242 static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
243 static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
244 static GstBusSyncReply bin_bus_handler (GstBus * bus,
245 GstMessage * message, GstBin * bin);
246 static gboolean gst_bin_query (GstElement * element, GstQuery * query);
247 static void gst_bin_set_context (GstElement * element, GstContext * context);
249 static gboolean gst_bin_do_latency_func (GstBin * bin);
251 static void bin_remove_messages (GstBin * bin, GstObject * src,
252 GstMessageType types);
253 static void gst_bin_continue_func (BinContinueData * data);
254 static gint bin_element_is_sink (GstElement * child, GstBin * bin);
255 static gint bin_element_is_src (GstElement * child, GstBin * bin);
257 static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
259 /* Bin signals and properties */
268 #define DEFAULT_ASYNC_HANDLING FALSE
269 #define DEFAULT_MESSAGE_FORWARD FALSE
275 PROP_MESSAGE_FORWARD,
279 static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
281 static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
285 static const GInterfaceInfo iface_info = { \
286 gst_bin_child_proxy_init, \
290 g_type_add_interface_static (g_define_type_id, GST_TYPE_CHILD_PROXY, &iface_info); \
292 GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
293 "debugging info for the 'bin' container element"); \
297 #define gst_bin_parent_class parent_class
298 G_DEFINE_TYPE_WITH_CODE (GstBin, gst_bin, GST_TYPE_ELEMENT, _do_init);
301 gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
307 bin = GST_BIN_CAST (child_proxy);
309 GST_OBJECT_LOCK (bin);
310 if ((res = g_list_nth_data (bin->children, index)))
311 gst_object_ref (res);
312 GST_OBJECT_UNLOCK (bin);
314 return (GObject *) res;
318 gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
323 bin = GST_BIN_CAST (child_proxy);
325 GST_OBJECT_LOCK (bin);
326 num = bin->numchildren;
327 GST_OBJECT_UNLOCK (bin);
333 gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
335 GstChildProxyInterface *iface = g_iface;
337 iface->get_children_count = gst_bin_child_proxy_get_children_count;
338 iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
342 _gst_boolean_accumulator (GSignalInvocationHint * ihint,
343 GValue * return_accu, const GValue * handler_return, gpointer dummy)
347 myboolean = g_value_get_boolean (handler_return);
348 if (!(ihint->run_type & G_SIGNAL_RUN_CLEANUP))
349 g_value_set_boolean (return_accu, myboolean);
351 GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
358 gst_bin_class_init (GstBinClass * klass)
360 GObjectClass *gobject_class;
361 GstElementClass *gstelement_class;
364 gobject_class = (GObjectClass *) klass;
365 gstelement_class = (GstElementClass *) klass;
367 g_type_class_add_private (klass, sizeof (GstBinPrivate));
369 gobject_class->set_property = gst_bin_set_property;
370 gobject_class->get_property = gst_bin_get_property;
373 * GstBin:async-handling:
375 * If set to #TRUE, the bin will handle asynchronous state changes.
376 * This should be used only if the bin subclass is modifying the state
377 * of its children on its own.
379 g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
380 g_param_spec_boolean ("async-handling", "Async Handling",
381 "The bin will handle Asynchronous state changes",
382 DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
385 * GstBin::element-added:
387 * @element: the #GstElement that was added to the bin
389 * Will be emitted after the element was added to the bin.
391 gst_bin_signals[ELEMENT_ADDED] =
392 g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
393 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
394 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
396 * GstBin::element-removed:
398 * @element: the #GstElement that was removed from the bin
400 * Will be emitted after the element was removed from the bin.
402 gst_bin_signals[ELEMENT_REMOVED] =
403 g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
404 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
405 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
407 * GstBin::do-latency:
410 * Will be emitted when the bin needs to perform latency calculations. This
411 * signal is only emited for toplevel bins or when async-handling is
414 * Only one signal handler is invoked. If no signals are connected, the
415 * default handler is invoked, which will query and distribute the lowest
416 * possible latency to all sinks.
418 * Connect to this signal if the default latency calculations are not
419 * sufficient, like when you need different latencies for different sinks in
422 gst_bin_signals[DO_LATENCY] =
423 g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
424 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
425 _gst_boolean_accumulator, NULL, g_cclosure_marshal_generic,
426 G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
429 * GstBin:message-forward:
431 * Forward all children messages, even those that would normally be filtered by
432 * the bin. This can be interesting when one wants to be notified of the EOS
433 * state of individual elements, for example.
435 * The messages are converted to an ELEMENT message with the bin as the
436 * source. The structure of the message is named 'GstBinForwarded' and contains
437 * a field named 'message' of type GST_TYPE_MESSAGE that contains the original
440 g_object_class_install_property (gobject_class, PROP_MESSAGE_FORWARD,
441 g_param_spec_boolean ("message-forward", "Message Forward",
442 "Forwards all children messages",
443 DEFAULT_MESSAGE_FORWARD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
445 gobject_class->dispose = gst_bin_dispose;
447 gst_element_class_set_static_metadata (gstelement_class, "Generic bin",
449 "Simple container object",
450 "Erik Walthinsen <omega@cse.ogi.edu>,"
451 "Wim Taymans <wim.taymans@gmail.com>");
453 gstelement_class->change_state =
454 GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
455 gstelement_class->state_changed = GST_DEBUG_FUNCPTR (gst_bin_state_changed);
456 gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
458 gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
459 gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
461 gstelement_class->provide_clock =
462 GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
463 gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
465 gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
466 gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
467 gstelement_class->set_context = GST_DEBUG_FUNCPTR (gst_bin_set_context);
469 klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
470 klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
471 klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
473 klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
475 GST_DEBUG ("creating bin thread pool");
478 g_thread_pool_new ((GFunc) gst_bin_continue_func, NULL, -1, FALSE, &err);
480 g_critical ("could alloc threadpool %s", err->message);
485 gst_bin_init (GstBin * bin)
489 bin->numchildren = 0;
490 bin->children = NULL;
491 bin->children_cookie = 0;
492 bin->messages = NULL;
493 bin->provided_clock = NULL;
494 bin->clock_dirty = FALSE;
496 /* Set up a bus for listening to child elements */
497 bus = g_object_new (GST_TYPE_BUS, "enable-async", FALSE, NULL);
498 bin->child_bus = bus;
499 GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
501 gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin,
504 bin->priv = GST_BIN_GET_PRIVATE (bin);
505 bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
506 bin->priv->structure_cookie = 0;
507 bin->priv->message_forward = DEFAULT_MESSAGE_FORWARD;
511 gst_bin_dispose (GObject * object)
513 GstBin *bin = GST_BIN_CAST (object);
514 GstBus **child_bus_p = &bin->child_bus;
515 GstClock **provided_clock_p = &bin->provided_clock;
516 GstElement **clock_provider_p = &bin->clock_provider;
518 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "dispose");
520 GST_OBJECT_LOCK (object);
521 gst_object_replace ((GstObject **) child_bus_p, NULL);
522 gst_object_replace ((GstObject **) provided_clock_p, NULL);
523 gst_object_replace ((GstObject **) clock_provider_p, NULL);
524 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
525 GST_OBJECT_UNLOCK (object);
527 while (bin->children) {
528 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
530 if (G_UNLIKELY (bin->children != NULL)) {
531 g_critical ("could not remove elements from bin '%s'",
532 GST_STR_NULL (GST_OBJECT_NAME (object)));
535 G_OBJECT_CLASS (parent_class)->dispose (object);
540 * @name: the name of the new bin
542 * Creates a new bin with the given name.
544 * Returns: (transfer floating): a new #GstBin
547 gst_bin_new (const gchar * name)
549 return gst_element_factory_make ("bin", name);
553 gst_bin_set_property (GObject * object, guint prop_id,
554 const GValue * value, GParamSpec * pspec)
558 gstbin = GST_BIN_CAST (object);
561 case PROP_ASYNC_HANDLING:
562 GST_OBJECT_LOCK (gstbin);
563 gstbin->priv->asynchandling = g_value_get_boolean (value);
564 GST_OBJECT_UNLOCK (gstbin);
566 case PROP_MESSAGE_FORWARD:
567 GST_OBJECT_LOCK (gstbin);
568 gstbin->priv->message_forward = g_value_get_boolean (value);
569 GST_OBJECT_UNLOCK (gstbin);
572 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
578 gst_bin_get_property (GObject * object, guint prop_id,
579 GValue * value, GParamSpec * pspec)
583 gstbin = GST_BIN_CAST (object);
586 case PROP_ASYNC_HANDLING:
587 GST_OBJECT_LOCK (gstbin);
588 g_value_set_boolean (value, gstbin->priv->asynchandling);
589 GST_OBJECT_UNLOCK (gstbin);
591 case PROP_MESSAGE_FORWARD:
592 GST_OBJECT_LOCK (gstbin);
593 g_value_set_boolean (value, gstbin->priv->message_forward);
594 GST_OBJECT_UNLOCK (gstbin);
597 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
603 /* return the cached index */
605 gst_bin_get_index_func (GstElement * element)
610 bin = GST_BIN_CAST (element);
612 GST_OBJECT_LOCK (bin);
613 if ((result = bin->priv->index))
614 gst_object_ref (result);
615 GST_OBJECT_UNLOCK (bin);
620 /* set the index on all elements in this bin
625 gst_bin_set_index_func (GstElement * element, GstIndex * index)
631 GValue data = { 0, };
633 bin = GST_BIN_CAST (element);
635 GST_OBJECT_LOCK (bin);
636 old = bin->priv->index;
637 if (G_UNLIKELY (old == index))
640 gst_object_ref (index);
641 bin->priv->index = index;
642 GST_OBJECT_UNLOCK (bin);
645 gst_object_unref (old);
647 it = gst_bin_iterate_elements (bin);
649 /* set the index on all elements in the bin */
652 switch (gst_iterator_next (it, &data)) {
653 case GST_ITERATOR_OK:
655 GstElement *child = g_value_get_object (&data);
657 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
658 GST_ELEMENT_NAME (child));
659 gst_element_set_index (child, index);
661 g_value_reset (&data);
664 case GST_ITERATOR_RESYNC:
665 GST_DEBUG_OBJECT (bin, "iterator doing resync");
666 gst_iterator_resync (it);
669 case GST_ITERATOR_DONE:
670 GST_DEBUG_OBJECT (bin, "iterator done");
675 g_value_unset (&data);
676 gst_iterator_free (it);
681 GST_DEBUG_OBJECT (bin, "index was already set");
682 GST_OBJECT_UNLOCK (bin);
688 /* set the clock on all elements in this bin
693 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
699 GValue data = { 0, };
701 bin = GST_BIN_CAST (element);
703 it = gst_bin_iterate_elements (bin);
707 switch (gst_iterator_next (it, &data)) {
708 case GST_ITERATOR_OK:
710 GstElement *child = g_value_get_object (&data);
712 res &= gst_element_set_clock (child, clock);
714 g_value_reset (&data);
717 case GST_ITERATOR_RESYNC:
718 GST_DEBUG_OBJECT (bin, "iterator doing resync");
719 gst_iterator_resync (it);
723 case GST_ITERATOR_DONE:
724 GST_DEBUG_OBJECT (bin, "iterator done");
729 g_value_unset (&data);
730 gst_iterator_free (it);
733 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
738 /* get the clock for this bin by asking all of the children in this bin
740 * The ref of the returned clock in increased so unref after usage.
742 * We loop the elements in state order and pick the last clock we can
743 * get. This makes sure we get a clock from the source.
748 gst_bin_provide_clock_func (GstElement * element)
750 GstClock *result = NULL;
751 GstElement *provider = NULL;
756 GstClock **provided_clock_p;
757 GstElement **clock_provider_p;
759 bin = GST_BIN_CAST (element);
761 GST_OBJECT_LOCK (bin);
762 if (!bin->clock_dirty)
765 GST_DEBUG_OBJECT (bin, "finding new clock");
767 it = gst_bin_sort_iterator_new (bin);
768 GST_OBJECT_UNLOCK (bin);
772 switch (gst_iterator_next (it, &val)) {
773 case GST_ITERATOR_OK:
775 GstElement *child = g_value_get_object (&val);
778 clock = gst_element_provide_clock (child);
780 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
781 clock, GST_ELEMENT_NAME (child));
783 gst_object_unref (result);
784 gst_object_unref (provider);
787 provider = gst_object_ref (child);
790 g_value_reset (&val);
793 case GST_ITERATOR_RESYNC:
794 gst_iterator_resync (it);
797 case GST_ITERATOR_DONE:
802 g_value_unset (&val);
803 gst_iterator_free (it);
805 GST_OBJECT_LOCK (bin);
806 if (!bin->clock_dirty) {
808 gst_object_unref (provider);
810 gst_object_unref (result);
816 provided_clock_p = &bin->provided_clock;
817 clock_provider_p = &bin->clock_provider;
818 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
819 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
820 bin->clock_dirty = FALSE;
821 GST_DEBUG_OBJECT (bin,
822 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
824 /* Provider is not being returned to caller, just the result */
826 gst_object_unref (provider);
827 GST_OBJECT_UNLOCK (bin);
833 if ((result = bin->provided_clock))
834 gst_object_ref (result);
835 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
836 GST_OBJECT_UNLOCK (bin);
843 * functions for manipulating cached messages
848 GstMessageType types;
851 /* check if a message is of given src and type */
853 message_check (GstMessage * message, MessageFind * target)
858 eq &= GST_MESSAGE_SRC (message) == target->src;
860 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
861 GST_LOG ("looking at message %p: %d", message, eq);
867 find_message (GstBin * bin, GstObject * src, GstMessageType types)
875 result = g_list_find_custom (bin->messages, &find,
876 (GCompareFunc) message_check);
879 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
880 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
883 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
884 #ifndef GST_DISABLE_GST_DEBUG
888 for (i = 0; i < 32; i++)
889 if (types & (1 << i))
890 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1 << 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)
1019 gint n_stream_start = 0;
1023 for (walk = bin->children; walk; walk = g_list_next (walk)) {
1024 GstElement *element;
1026 element = GST_ELEMENT_CAST (walk->data);
1027 if (bin_element_is_sink (element, bin) == 0) {
1028 /* check if element posted STREAM_START */
1030 find_message (bin, GST_OBJECT_CAST (element),
1031 GST_MESSAGE_STREAM_START))) {
1032 GST_DEBUG ("sink '%s' posted STREAM_START", GST_ELEMENT_NAME (element));
1033 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1036 GST_DEBUG ("sink '%s' did not post STREAM_START yet",
1037 GST_ELEMENT_NAME (element));
1048 unlink_pads (const GValue * item, gpointer user_data)
1053 pad = g_value_get_object (item);
1055 if ((peer = gst_pad_get_peer (pad))) {
1056 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
1057 gst_pad_unlink (pad, peer);
1059 gst_pad_unlink (peer, pad);
1060 gst_object_unref (peer);
1064 /* vmethod that adds an element to a bin
1069 gst_bin_add_func (GstBin * bin, GstElement * element)
1073 gboolean is_sink, is_source, provides_clock, requires_clock;
1074 GstMessage *clock_message = NULL, *async_message = NULL;
1075 GstStateChangeReturn ret;
1077 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1079 /* we obviously can't add ourself to ourself */
1080 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1083 /* get the element name to make sure it is unique in this bin. */
1084 GST_OBJECT_LOCK (element);
1085 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1086 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1087 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1089 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1091 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1092 GST_OBJECT_UNLOCK (element);
1094 GST_OBJECT_LOCK (bin);
1096 /* then check to see if the element's name is already taken in the bin,
1097 * we can safely take the lock here. This check is probably bogus because
1098 * you can safely change the element name after this check and before setting
1099 * the object parent. The window is very small though... */
1100 if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
1101 goto duplicate_name;
1103 /* set the element's parent and add the element to the bin's list of children */
1104 if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
1105 GST_OBJECT_CAST (bin))))
1108 /* if we add a sink we become a sink */
1110 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
1112 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SINK);
1115 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was source",
1117 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SOURCE);
1119 if (provides_clock) {
1120 GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
1122 gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
1123 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1125 if (requires_clock) {
1126 GST_DEBUG_OBJECT (bin, "element \"%s\" requires a clock", elem_name);
1127 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1130 bin->children = g_list_prepend (bin->children, element);
1132 bin->children_cookie++;
1133 if (!GST_BIN_IS_NO_RESYNC (bin))
1134 bin->priv->structure_cookie++;
1136 /* distribute the bus */
1137 gst_element_set_bus (element, bin->child_bus);
1139 /* propagate the current base_time, start_time and clock */
1140 gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
1141 gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
1142 /* it's possible that the element did not accept the clock but
1143 * that is not important right now. When the pipeline goes to PLAYING,
1144 * a new clock will be selected */
1145 gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
1147 if (bin->priv->context)
1148 gst_element_set_context (element, bin->priv->context);
1151 /* set the cached index on the children */
1152 if (bin->priv->index)
1153 gst_element_set_index (element, bin->priv->index);
1156 ret = GST_STATE_RETURN (bin);
1157 /* no need to update the state if we are in error */
1158 if (ret == GST_STATE_CHANGE_FAILURE)
1159 goto no_state_recalc;
1161 /* update the bin state, the new element could have been an ASYNC or
1162 * NO_PREROLL element */
1163 ret = GST_STATE_RETURN (element);
1164 GST_DEBUG_OBJECT (bin, "added %s element",
1165 gst_element_state_change_return_get_name (ret));
1168 case GST_STATE_CHANGE_ASYNC:
1170 /* create message to track this aync element when it posts an async-done
1172 async_message = gst_message_new_async_start (GST_OBJECT_CAST (element));
1175 case GST_STATE_CHANGE_NO_PREROLL:
1176 /* ignore all async elements we might have and commit our state */
1177 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1179 case GST_STATE_CHANGE_FAILURE:
1186 GST_OBJECT_UNLOCK (bin);
1188 /* post the messages on the bus of the element so that the bin can handle
1191 gst_element_post_message (element, clock_message);
1194 gst_element_post_message (element, async_message);
1196 /* unlink all linked pads */
1197 it = gst_element_iterate_pads (element);
1198 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1199 gst_iterator_free (it);
1201 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
1204 g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
1205 gst_child_proxy_child_added ((GstChildProxy *) bin, (GObject *) element,
1212 /* ERROR handling here */
1215 GST_OBJECT_LOCK (bin);
1216 g_warning ("Cannot add bin '%s' to itself", GST_ELEMENT_NAME (bin));
1217 GST_OBJECT_UNLOCK (bin);
1222 g_warning ("Name '%s' is not unique in bin '%s', not adding",
1223 elem_name, GST_ELEMENT_NAME (bin));
1224 GST_OBJECT_UNLOCK (bin);
1230 g_warning ("Element '%s' already has parent", elem_name);
1231 GST_OBJECT_UNLOCK (bin);
1240 * @element: (transfer full): the #GstElement to add
1242 * Adds the given element to the bin. Sets the element's parent, and thus
1243 * takes ownership of the element. An element can only be added to one bin.
1245 * If the element's pads are linked to other pads, the pads will be unlinked
1246 * before the element is added to the bin.
1249 * When you add an element to an already-running pipeline, you will have to
1250 * take care to set the state of the newly-added element to the desired
1251 * state (usually PLAYING or PAUSED, same you set the pipeline to originally)
1252 * with gst_element_set_state(), or use gst_element_sync_state_with_parent().
1253 * The bin or pipeline will not take care of this for you.
1258 * Returns: TRUE if the element could be added, FALSE if
1259 * the bin does not want to accept the element.
1262 gst_bin_add (GstBin * bin, GstElement * element)
1264 GstBinClass *bclass;
1267 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1268 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1270 bclass = GST_BIN_GET_CLASS (bin);
1272 if (G_UNLIKELY (bclass->add_element == NULL))
1275 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1276 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1277 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1279 result = bclass->add_element (bin, element);
1283 /* ERROR handling */
1286 g_warning ("adding elements to bin '%s' is not supported",
1287 GST_ELEMENT_NAME (bin));
1292 /* remove an element from the bin
1297 gst_bin_remove_func (GstBin * bin, GstElement * element)
1301 gboolean is_sink, is_source, provides_clock, requires_clock;
1302 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1303 GstMessage *clock_message = NULL;
1304 GstClock **provided_clock_p;
1305 GstElement **clock_provider_p;
1307 gboolean other_async, this_async, have_no_preroll;
1308 GstStateChangeReturn ret;
1310 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1312 GST_OBJECT_LOCK (bin);
1314 GST_OBJECT_LOCK (element);
1315 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1317 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1320 /* remove the parent ref */
1321 GST_OBJECT_PARENT (element) = NULL;
1323 /* grab element name so we can print it */
1324 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1325 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1327 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1329 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1330 GST_OBJECT_UNLOCK (element);
1334 othersource = FALSE;
1335 otherprovider = FALSE;
1336 otherrequirer = FALSE;
1337 have_no_preroll = FALSE;
1338 /* iterate the elements, we collect which ones are async and no_preroll. We
1339 * also remove the element when we find it. */
1340 for (walk = bin->children; walk; walk = next) {
1341 GstElement *child = GST_ELEMENT_CAST (walk->data);
1343 next = g_list_next (walk);
1345 if (child == element) {
1347 /* remove the element */
1348 bin->children = g_list_delete_link (bin->children, walk);
1350 gboolean child_sink, child_source, child_provider, child_requirer;
1352 GST_OBJECT_LOCK (child);
1353 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1354 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1356 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1358 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1359 /* when we remove a sink, check if there are other sinks. */
1360 if (is_sink && !othersink && child_sink)
1362 if (is_source && !othersource && child_source)
1364 if (provides_clock && !otherprovider && child_provider)
1365 otherprovider = TRUE;
1366 if (requires_clock && !otherrequirer && child_requirer)
1367 otherrequirer = TRUE;
1368 /* check if we have NO_PREROLL children */
1369 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1370 have_no_preroll = TRUE;
1371 GST_OBJECT_UNLOCK (child);
1375 /* the element must have been in the bin's list of children */
1376 if (G_UNLIKELY (!found))
1379 /* we now removed the element from the list of elements, increment the cookie
1380 * so that others can detect a change in the children list. */
1382 bin->children_cookie++;
1383 if (!GST_BIN_IS_NO_RESYNC (bin))
1384 bin->priv->structure_cookie++;
1386 if (is_sink && !othersink) {
1387 /* we're not a sink anymore */
1388 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1389 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1391 if (is_source && !othersource) {
1392 /* we're not a source anymore */
1393 GST_DEBUG_OBJECT (bin, "we removed the last source");
1394 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1396 if (provides_clock && !otherprovider) {
1397 /* we're not a clock provider anymore */
1398 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1399 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1401 if (requires_clock && !otherrequirer) {
1402 /* we're not a clock requirer anymore */
1403 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1404 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1407 /* if the clock provider for this element is removed, we lost
1408 * the clock as well, we need to inform the parent of this
1409 * so that it can select a new clock */
1410 if (bin->clock_provider == element) {
1411 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1412 bin->clock_dirty = TRUE;
1414 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1415 provided_clock_p = &bin->provided_clock;
1416 clock_provider_p = &bin->clock_provider;
1417 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1418 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1421 /* remove messages for the element, if there was a pending ASYNC_START
1422 * message we must see if removing the element caused the bin to lose its
1425 other_async = FALSE;
1426 for (walk = bin->messages; walk; walk = next) {
1427 GstMessage *message = (GstMessage *) walk->data;
1428 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1431 next = g_list_next (walk);
1434 switch (GST_MESSAGE_TYPE (message)) {
1435 case GST_MESSAGE_ASYNC_START:
1441 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1443 case GST_MESSAGE_STRUCTURE_CHANGE:
1447 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1449 /* it's unlikely that this message is still in the list of messages
1450 * because this would mean that a link/unlink is busy in another thread
1451 * while we remove the element. We still have to remove the message
1452 * because we might not receive the done message anymore when the element
1453 * is removed from the bin. */
1454 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1455 if (owner == element)
1466 /* delete all message types */
1467 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1468 message, elem_name);
1469 bin->messages = g_list_delete_link (bin->messages, walk);
1470 gst_message_unref (message);
1474 /* get last return */
1475 ret = GST_STATE_RETURN (bin);
1477 /* no need to update the state if we are in error */
1478 if (ret == GST_STATE_CHANGE_FAILURE)
1479 goto no_state_recalc;
1481 if (!other_async && this_async) {
1482 /* all other elements were not async and we removed the async one,
1483 * handle the async-done case because we are not async anymore now. */
1484 GST_DEBUG_OBJECT (bin,
1485 "we removed the last async element, have no_preroll %d",
1488 /* the current state return of the bin depends on if there are no_preroll
1489 * elements in the pipeline or not */
1490 if (have_no_preroll)
1491 ret = GST_STATE_CHANGE_NO_PREROLL;
1493 ret = GST_STATE_CHANGE_SUCCESS;
1495 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1497 GST_DEBUG_OBJECT (bin,
1498 "recalc state preroll: %d, other async: %d, this async %d",
1499 have_no_preroll, other_async, this_async);
1501 if (have_no_preroll) {
1502 ret = GST_STATE_CHANGE_NO_PREROLL;
1503 } else if (other_async) {
1504 /* there are other async elements and we were not doing an async state
1505 * change, change our pending state and go async */
1506 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1507 GST_STATE_NEXT (bin) = GST_STATE (bin);
1508 GST_STATE_PENDING (bin) = GST_STATE (bin);
1510 ret = GST_STATE_CHANGE_ASYNC;
1512 GST_STATE_RETURN (bin) = ret;
1516 gst_element_set_bus (element, NULL);
1517 /* Clear the clock we provided to the element */
1518 gst_element_set_clock (element, NULL);
1519 GST_OBJECT_UNLOCK (bin);
1522 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1524 /* unlink all linked pads */
1525 it = gst_element_iterate_pads (element);
1526 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1527 gst_iterator_free (it);
1529 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1532 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1533 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1537 /* element is really out of our control now */
1538 gst_object_unref (element);
1542 /* ERROR handling */
1545 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1546 GST_ELEMENT_NAME (bin));
1547 GST_OBJECT_UNLOCK (element);
1548 GST_OBJECT_UNLOCK (bin);
1557 * @element: (transfer none): the #GstElement to remove
1559 * Removes the element from the bin, unparenting it as well.
1560 * Unparenting the element means that the element will be dereferenced,
1561 * so if the bin holds the only reference to the element, the element
1562 * will be freed in the process of removing it from the bin. If you
1563 * want the element to still exist after removing, you need to call
1564 * gst_object_ref() before removing it from the bin.
1566 * If the element's pads are linked to other pads, the pads will be unlinked
1567 * before the element is removed from the bin.
1571 * Returns: TRUE if the element could be removed, FALSE if
1572 * the bin does not want to remove the element.
1575 gst_bin_remove (GstBin * bin, GstElement * element)
1577 GstBinClass *bclass;
1580 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1581 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1583 bclass = GST_BIN_GET_CLASS (bin);
1585 if (G_UNLIKELY (bclass->remove_element == NULL))
1588 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1589 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1591 result = bclass->remove_element (bin, element);
1595 /* ERROR handling */
1598 g_warning ("removing elements from bin '%s' is not supported",
1599 GST_ELEMENT_NAME (bin));
1605 * gst_bin_iterate_elements:
1608 * Gets an iterator for the elements in this bin.
1610 * MT safe. Caller owns returned value.
1612 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1615 gst_bin_iterate_elements (GstBin * bin)
1617 GstIterator *result;
1619 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1621 GST_OBJECT_LOCK (bin);
1622 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1623 GST_OBJECT_GET_LOCK (bin),
1624 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1625 GST_OBJECT_UNLOCK (bin);
1630 static GstIteratorItem
1631 iterate_child_recurse (GstIterator * it, const GValue * item)
1633 GstElement *child = g_value_get_object (item);
1635 if (GST_IS_BIN (child)) {
1636 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1638 gst_iterator_push (it, other);
1640 return GST_ITERATOR_ITEM_PASS;
1644 * gst_bin_iterate_recurse:
1647 * Gets an iterator for the elements in this bin.
1648 * This iterator recurses into GstBin children.
1650 * MT safe. Caller owns returned value.
1652 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1655 gst_bin_iterate_recurse (GstBin * bin)
1657 GstIterator *result;
1659 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1661 GST_OBJECT_LOCK (bin);
1662 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1663 GST_OBJECT_GET_LOCK (bin),
1664 &bin->children_cookie,
1666 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1667 GST_OBJECT_UNLOCK (bin);
1672 /* returns 0 when TRUE because this is a GCompareFunc */
1675 bin_element_is_sink (GstElement * child, GstBin * bin)
1679 /* we lock the child here for the remainder of the function to
1680 * get its name and flag safely. */
1681 GST_OBJECT_LOCK (child);
1682 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1684 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1685 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1687 GST_OBJECT_UNLOCK (child);
1688 return is_sink ? 0 : 1;
1692 sink_iterator_filter (const GValue * vchild, GValue * vbin)
1694 GstBin *bin = g_value_get_object (vbin);
1695 GstElement *child = g_value_get_object (vchild);
1697 return (bin_element_is_sink (child, bin));
1701 * gst_bin_iterate_sinks:
1704 * Gets an iterator for all elements in the bin that have the
1705 * #GST_ELEMENT_FLAG_SINK flag set.
1707 * MT safe. Caller owns returned value.
1709 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1712 gst_bin_iterate_sinks (GstBin * bin)
1714 GstIterator *children;
1715 GstIterator *result;
1716 GValue vbin = { 0, };
1718 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1720 g_value_init (&vbin, GST_TYPE_BIN);
1721 g_value_set_object (&vbin, bin);
1723 children = gst_bin_iterate_elements (bin);
1724 result = gst_iterator_filter (children,
1725 (GCompareFunc) sink_iterator_filter, &vbin);
1727 g_value_unset (&vbin);
1732 /* returns 0 when TRUE because this is a GCompareFunc */
1735 bin_element_is_src (GstElement * child, GstBin * bin)
1739 /* we lock the child here for the remainder of the function to
1740 * get its name and other info safely. */
1741 GST_OBJECT_LOCK (child);
1742 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1744 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1745 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
1747 GST_OBJECT_UNLOCK (child);
1748 return is_src ? 0 : 1;
1752 src_iterator_filter (const GValue * vchild, GValue * vbin)
1754 GstBin *bin = g_value_get_object (vbin);
1755 GstElement *child = g_value_get_object (vchild);
1757 return (bin_element_is_src (child, bin));
1761 * gst_bin_iterate_sources:
1764 * Gets an iterator for all elements in the bin that have the
1765 * #GST_ELEMENT_FLAG_SOURCE flag set.
1767 * MT safe. Caller owns returned value.
1769 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
1772 gst_bin_iterate_sources (GstBin * bin)
1774 GstIterator *children;
1775 GstIterator *result;
1776 GValue vbin = { 0, };
1778 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1780 g_value_init (&vbin, GST_TYPE_BIN);
1781 g_value_set_object (&vbin, bin);
1783 children = gst_bin_iterate_elements (bin);
1784 result = gst_iterator_filter (children,
1785 (GCompareFunc) src_iterator_filter, &vbin);
1787 g_value_unset (&vbin);
1795 static GstStateChangeReturn
1796 gst_bin_get_state_func (GstElement * element, GstState * state,
1797 GstState * pending, GstClockTime timeout)
1799 GstStateChangeReturn ret;
1801 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
1804 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
1810 /***********************************************
1811 * Topologically sorted iterator
1812 * see http://en.wikipedia.org/wiki/Topological_sorting
1814 * For each element in the graph, an entry is kept in a HashTable
1815 * with its number of srcpad connections (degree).
1816 * We then change state of all elements without dependencies
1817 * (degree 0) and decrement the degree of all elements connected
1818 * on the sinkpads. When an element reaches degree 0, its state is
1820 * When all elements are handled the algorithm stops.
1822 typedef struct _GstBinSortIterator
1825 GQueue queue; /* elements queued for state change */
1826 GstBin *bin; /* bin we iterate */
1827 gint mode; /* adding or removing dependency */
1828 GstElement *best; /* next element with least dependencies */
1829 gint best_deg; /* best degree */
1830 GHashTable *hash; /* hashtable with element dependencies */
1831 gboolean dirty; /* we detected structure change */
1832 } GstBinSortIterator;
1835 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
1836 GstBinSortIterator * copy)
1838 GHashTableIter iter;
1839 gpointer key, value;
1841 copy->queue = it->queue;
1842 g_queue_foreach (©->queue, (GFunc) gst_object_ref, NULL);
1844 copy->bin = gst_object_ref (it->bin);
1846 copy->best = gst_object_ref (it->best);
1848 copy->hash = g_hash_table_new (NULL, NULL);
1849 g_hash_table_iter_init (&iter, it->hash);
1850 while (g_hash_table_iter_next (&iter, &key, &value))
1851 g_hash_table_insert (copy->hash, key, value);
1854 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
1855 #define HASH_SET_DEGREE(bit, elem, deg) \
1856 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
1857 #define HASH_GET_DEGREE(bit, elem) \
1858 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
1860 /* add element to queue of next elements in the iterator.
1861 * We push at the tail to give higher priority elements a
1864 add_to_queue (GstBinSortIterator * bit, GstElement * element)
1866 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
1867 GST_ELEMENT_NAME (element));
1868 gst_object_ref (element);
1869 g_queue_push_tail (&bit->queue, element);
1870 HASH_SET_DEGREE (bit, element, -1);
1874 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
1878 if ((find = g_queue_find (&bit->queue, element))) {
1879 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
1880 GST_ELEMENT_NAME (element));
1882 g_queue_delete_link (&bit->queue, find);
1883 gst_object_unref (element);
1885 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
1886 GST_ELEMENT_NAME (element));
1890 /* clear the queue, unref all objects as we took a ref when
1891 * we added them to the queue */
1893 clear_queue (GQueue * queue)
1897 while ((p = g_queue_pop_head (queue)))
1898 gst_object_unref (p);
1901 /* set all degrees to 0. Elements marked as a sink are
1902 * added to the queue immediately. Since we only look at the SINK flag of the
1903 * element, it is possible that we add non-sinks to the queue. These will be
1904 * removed from the queue again when we can prove that it provides data for some
1907 reset_degree (GstElement * element, GstBinSortIterator * bit)
1911 /* sinks are added right away */
1912 GST_OBJECT_LOCK (element);
1913 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1914 GST_OBJECT_UNLOCK (element);
1917 add_to_queue (bit, element);
1919 /* others are marked with 0 and handled when sinks are done */
1920 HASH_SET_DEGREE (bit, element, 0);
1924 /* adjust the degree of all elements connected to the given
1925 * element. If a degree of an element drops to 0, it is
1926 * added to the queue of elements to schedule next.
1928 * We have to make sure not to cross the bin boundary this element
1932 update_degree (GstElement * element, GstBinSortIterator * bit)
1934 gboolean linked = FALSE;
1936 GST_OBJECT_LOCK (element);
1937 /* don't touch degree if element has no sinkpads */
1938 if (element->numsinkpads != 0) {
1939 /* loop over all sinkpads, decrement degree for all connected
1940 * elements in this bin */
1943 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
1946 pad = GST_PAD_CAST (pads->data);
1948 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
1949 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
1950 GST_MESSAGE_STRUCTURE_CHANGE))) {
1951 /* mark the iterator as dirty because we won't be updating the degree
1952 * of the peer parent now. This would result in the 'loop detected'
1953 * later on because the peer parent element could become the best next
1954 * element with a degree > 0. We will simply continue our state
1955 * changes and we'll eventually resync when the unlink completed and
1956 * the iterator cookie is updated. */
1961 if ((peer = gst_pad_get_peer (pad))) {
1962 GstElement *peer_element;
1964 if ((peer_element = gst_pad_get_parent_element (peer))) {
1965 GST_OBJECT_LOCK (peer_element);
1966 /* check that we don't go outside of this bin */
1967 if (GST_OBJECT_CAST (peer_element)->parent ==
1968 GST_OBJECT_CAST (bit->bin)) {
1969 gint old_deg, new_deg;
1971 old_deg = HASH_GET_DEGREE (bit, peer_element);
1973 /* check to see if we added an element as sink that was not really a
1974 * sink because it was connected to some other element. */
1975 if (old_deg == -1) {
1976 remove_from_queue (bit, peer_element);
1979 new_deg = old_deg + bit->mode;
1981 GST_DEBUG_OBJECT (bit->bin,
1982 "change element %s, degree %d->%d, linked to %s",
1983 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
1984 GST_ELEMENT_NAME (element));
1986 /* update degree, it is possible that an element was in 0 and
1987 * reaches -1 here. This would mean that the element had no sinkpads
1988 * but became linked while the state change was happening. We will
1989 * resync on this with the structure change message. */
1991 /* degree hit 0, add to queue */
1992 add_to_queue (bit, peer_element);
1994 HASH_SET_DEGREE (bit, peer_element, new_deg);
1998 GST_OBJECT_UNLOCK (peer_element);
1999 gst_object_unref (peer_element);
2001 gst_object_unref (peer);
2006 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2007 GST_ELEMENT_NAME (element));
2009 GST_OBJECT_UNLOCK (element);
2012 /* find the next best element not handled yet. This is the one
2013 * with the lowest non-negative degree */
2015 find_element (GstElement * element, GstBinSortIterator * bit)
2019 /* element is already handled */
2020 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2023 /* first element or element with smaller degree */
2024 if (bit->best == NULL || bit->best_deg > degree) {
2025 bit->best = element;
2026 bit->best_deg = degree;
2030 /* get next element in iterator. */
2031 static GstIteratorResult
2032 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2035 GstBin *bin = bit->bin;
2037 /* empty queue, we have to find a next best element */
2038 if (g_queue_is_empty (&bit->queue)) {
2040 bit->best_deg = G_MAXINT;
2041 g_list_foreach (bin->children, (GFunc) find_element, bit);
2042 if ((best = bit->best)) {
2043 /* when we detected an unlink, don't warn because our degrees might be
2044 * screwed up. We will resync later */
2045 if (bit->best_deg != 0 && !bit->dirty) {
2046 /* we don't fail on this one yet */
2047 GST_WARNING_OBJECT (bin, "loop dected in graph");
2048 g_warning ("loop detected in the graph of bin '%s'!!",
2049 GST_ELEMENT_NAME (bin));
2051 /* best unhandled element, schedule as next element */
2052 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2053 GST_ELEMENT_NAME (best));
2054 HASH_SET_DEGREE (bit, best, -1);
2055 g_value_set_object (result, best);
2057 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2058 /* no more unhandled elements, we are done */
2059 return GST_ITERATOR_DONE;
2062 /* everything added to the queue got reffed */
2063 best = g_queue_pop_head (&bit->queue);
2064 g_value_set_object (result, best);
2065 gst_object_unref (best);
2068 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2069 /* update degrees of linked elements */
2070 update_degree (best, bit);
2072 return GST_ITERATOR_OK;
2075 /* clear queues, recalculate the degrees and restart. */
2077 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2079 GstBin *bin = bit->bin;
2081 GST_DEBUG_OBJECT (bin, "resync");
2083 clear_queue (&bit->queue);
2085 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2086 /* calc degrees, incrementing */
2088 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2089 /* for the rest of the function we decrement the degrees */
2093 /* clear queues, unref bin and free iterator. */
2095 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2097 GstBin *bin = bit->bin;
2099 GST_DEBUG_OBJECT (bin, "free");
2100 clear_queue (&bit->queue);
2101 g_hash_table_destroy (bit->hash);
2102 gst_object_unref (bin);
2105 /* should be called with the bin LOCK held */
2106 static GstIterator *
2107 gst_bin_sort_iterator_new (GstBin * bin)
2109 GstBinSortIterator *result;
2111 /* we don't need an ItemFunction because we ref the items in the _next
2113 result = (GstBinSortIterator *)
2114 gst_iterator_new (sizeof (GstBinSortIterator),
2116 GST_OBJECT_GET_LOCK (bin),
2117 &bin->priv->structure_cookie,
2118 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2119 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2120 (GstIteratorItemFunction) NULL,
2121 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2122 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2123 g_queue_init (&result->queue);
2124 result->hash = g_hash_table_new (NULL, NULL);
2125 gst_object_ref (bin);
2127 gst_bin_sort_iterator_resync (result);
2129 return (GstIterator *) result;
2133 * gst_bin_iterate_sorted:
2136 * Gets an iterator for the elements in this bin in topologically
2137 * sorted order. This means that the elements are returned from
2138 * the most downstream elements (sinks) to the sources.
2140 * This function is used internally to perform the state changes
2141 * of the bin elements and for clock selection.
2143 * MT safe. Caller owns returned value.
2145 * Returns: (transfer full): a #GstIterator of #GstElement, or NULL
2148 gst_bin_iterate_sorted (GstBin * bin)
2150 GstIterator *result;
2152 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2154 GST_OBJECT_LOCK (bin);
2155 result = gst_bin_sort_iterator_new (bin);
2156 GST_OBJECT_UNLOCK (bin);
2161 static GstStateChangeReturn
2162 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2163 GstClockTime base_time, GstClockTime start_time, GstState current,
2166 GstStateChangeReturn ret;
2167 GstState child_current, child_pending;
2171 GST_STATE_LOCK (element);
2173 GST_OBJECT_LOCK (element);
2174 /* set base_time and start time on child */
2175 GST_ELEMENT_START_TIME (element) = start_time;
2176 element->base_time = base_time;
2177 /* peel off the locked flag */
2178 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2179 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2180 ret = GST_STATE_RETURN (element);
2181 child_current = GST_STATE (element);
2182 child_pending = GST_STATE_PENDING (element);
2183 GST_OBJECT_UNLOCK (element);
2185 /* skip locked elements */
2186 if (G_UNLIKELY (locked))
2189 /* if the element was no preroll, just start changing the state regardless
2190 * if it had async elements (in the case of a bin) because they won't preroll
2192 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2193 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2197 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2198 "current %s pending %s, desired next %s",
2199 gst_element_state_get_name (child_current),
2200 gst_element_state_get_name (child_pending),
2201 gst_element_state_get_name (next));
2203 /* always recurse into bins so that we can set the base time */
2204 if (GST_IS_BIN (element))
2207 /* Try not to change the state of elements that are already in the state we're
2209 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2210 /* child is already at the requested state, return previous return. Note that
2211 * if the child has a pending state to next, we will still call the
2212 * set_state function */
2214 } else if (next > current) {
2215 /* upward state change */
2216 if (child_pending == GST_STATE_VOID_PENDING) {
2217 /* .. and the child is not busy doing anything */
2218 if (child_current > next) {
2219 /* .. and is already past the requested state, assume it got there
2221 ret = GST_STATE_CHANGE_SUCCESS;
2224 } else if (child_pending > child_current) {
2225 /* .. and the child is busy going upwards */
2226 if (child_current >= next) {
2227 /* .. and is already past the requested state, assume it got there
2229 ret = GST_STATE_CHANGE_SUCCESS;
2233 /* .. and the child is busy going downwards */
2234 if (child_current > next) {
2235 /* .. and is already past the requested state, assume it got there
2237 ret = GST_STATE_CHANGE_SUCCESS;
2241 } else if (next < current) {
2242 /* downward state change */
2243 if (child_pending == GST_STATE_VOID_PENDING) {
2244 /* .. and the child is not busy doing anything */
2245 if (child_current < next) {
2246 /* .. and is already past the requested state, assume it got there
2248 ret = GST_STATE_CHANGE_SUCCESS;
2251 } else if (child_pending < child_current) {
2252 /* .. and the child is busy going downwards */
2253 if (child_current <= next) {
2254 /* .. and is already past the requested state, assume it got there
2256 ret = GST_STATE_CHANGE_SUCCESS;
2260 /* .. and the child is busy going upwards */
2261 if (child_current < next) {
2262 /* .. and is already past the requested state, assume it got there
2264 ret = GST_STATE_CHANGE_SUCCESS;
2271 GST_OBJECT_LOCK (bin);
2272 /* the element was busy with an upwards async state change, we must wait for
2273 * an ASYNC_DONE message before we attemp to change the state. */
2275 find_message (bin, GST_OBJECT_CAST (element),
2276 GST_MESSAGE_ASYNC_START))) {
2277 #ifndef GST_DISABLE_GST_DEBUG
2278 GstMessage *message = GST_MESSAGE_CAST (found->data);
2280 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2281 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2283 /* only wait for upward state changes */
2284 if (next > current) {
2285 /* We found an async element check if we can force its state to change or
2286 * if we have to wait for it to preroll. */
2290 GST_OBJECT_UNLOCK (bin);
2293 GST_DEBUG_OBJECT (bin,
2294 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2295 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2296 GST_TIME_ARGS (base_time));
2299 ret = gst_element_set_state (element, next);
2301 GST_STATE_UNLOCK (element);
2307 GST_DEBUG_OBJECT (element,
2308 "element is locked, return previous return %s",
2309 gst_element_state_change_return_get_name (ret));
2310 GST_STATE_UNLOCK (element);
2315 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2316 "skipping transition from %s to %s",
2317 gst_element_state_get_name (child_current),
2318 gst_element_state_get_name (next));
2319 GST_STATE_UNLOCK (element);
2324 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2325 GST_OBJECT_UNLOCK (bin);
2326 GST_STATE_UNLOCK (element);
2327 return GST_STATE_CHANGE_ASYNC;
2331 /* gst_iterator_fold functions for pads_activate
2332 * Stop the iterator if activating one pad failed. */
2334 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2336 GstPad *pad = g_value_get_object (vpad);
2337 gboolean cont = TRUE;
2339 if (!(cont = gst_pad_set_active (pad, *active)))
2340 g_value_set_boolean (ret, FALSE);
2345 /* returns false on error or early cutout of the fold, true if all
2346 * pads in @iter were (de)activated successfully. */
2348 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2350 GstIteratorResult ires;
2353 /* no need to unset this later, it's just a boolean */
2354 g_value_init (&ret, G_TYPE_BOOLEAN);
2355 g_value_set_boolean (&ret, TRUE);
2358 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2361 case GST_ITERATOR_RESYNC:
2362 /* need to reset the result again */
2363 g_value_set_boolean (&ret, TRUE);
2364 gst_iterator_resync (iter);
2366 case GST_ITERATOR_DONE:
2367 /* all pads iterated, return collected value */
2370 /* iterator returned _ERROR or premature end with _OK,
2371 * mark an error and exit */
2372 g_value_set_boolean (&ret, FALSE);
2377 /* return collected value */
2378 return g_value_get_boolean (&ret);
2381 /* is called with STATE_LOCK
2384 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2389 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2391 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2392 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2393 gst_iterator_free (iter);
2394 if (G_UNLIKELY (!fold_ok))
2397 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2404 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2410 * gst_bin_recalculate_latency:
2413 * Query @bin for the current latency using and reconfigures this latency to all the
2414 * elements with a LATENCY event.
2416 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2417 * is posted on the bus.
2419 * This function simply emits the 'do-latency' signal so any custom latency
2420 * calculations will be performed.
2422 * Returns: %TRUE if the latency could be queried and reconfigured.
2425 gst_bin_recalculate_latency (GstBin * bin)
2429 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2430 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2436 gst_bin_do_latency_func (GstBin * bin)
2439 GstElement *element;
2440 GstClockTime min_latency, max_latency;
2443 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2445 element = GST_ELEMENT_CAST (bin);
2447 GST_DEBUG_OBJECT (element, "querying latency");
2449 query = gst_query_new_latency ();
2450 if ((res = gst_element_query (element, query))) {
2453 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2455 GST_DEBUG_OBJECT (element,
2456 "got min latency %" GST_TIME_FORMAT ", max latency %"
2457 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2458 GST_TIME_ARGS (max_latency), live);
2460 if (max_latency < min_latency) {
2461 /* this is an impossible situation, some parts of the pipeline might not
2462 * work correctly. We post a warning for now. */
2463 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2464 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2465 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2466 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2469 /* configure latency on elements */
2470 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2472 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2473 GST_TIME_ARGS (min_latency));
2475 GST_WARNING_OBJECT (element,
2476 "did not really configure latency of %" GST_TIME_FORMAT,
2477 GST_TIME_ARGS (min_latency));
2480 /* this is not a real problem, we just don't configure any latency. */
2481 GST_WARNING_OBJECT (element, "failed to query latency");
2483 gst_query_unref (query);
2489 gst_bin_state_changed (GstElement * element, GstState oldstate,
2490 GstState newstate, GstState pending)
2492 GstElementClass *pklass = (GstElementClass *) parent_class;
2494 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING)
2495 bin_do_eos (GST_BIN_CAST (element));
2497 if (pklass->state_changed)
2498 pklass->state_changed (element, oldstate, newstate, pending);
2501 static GstStateChangeReturn
2502 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2505 GstStateChangeReturn ret;
2506 GstState current, next;
2507 gboolean have_async;
2508 gboolean have_no_preroll;
2509 GstClockTime base_time, start_time;
2512 GValue data = { 0, };
2514 /* we don't need to take the STATE_LOCK, it is already taken */
2515 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2516 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2518 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2519 "changing state of children from %s to %s",
2520 gst_element_state_get_name (current), gst_element_state_get_name (next));
2522 bin = GST_BIN_CAST (element);
2525 case GST_STATE_PLAYING:
2529 GST_OBJECT_LOCK (bin);
2530 toplevel = BIN_IS_TOPLEVEL (bin);
2531 GST_OBJECT_UNLOCK (bin);
2534 gst_bin_recalculate_latency (bin);
2537 case GST_STATE_PAUSED:
2538 /* Clear EOS list on next PAUSED */
2539 GST_OBJECT_LOCK (bin);
2540 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2541 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2542 bin->priv->posted_eos = FALSE;
2543 if (current == GST_STATE_READY)
2544 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2545 GST_OBJECT_UNLOCK (bin);
2546 if (current == GST_STATE_READY)
2547 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2548 goto activate_failure;
2550 case GST_STATE_READY:
2551 /* Clear message list on next READY */
2552 GST_OBJECT_LOCK (bin);
2553 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2554 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2555 GST_OBJECT_UNLOCK (bin);
2556 if (current == GST_STATE_PAUSED)
2557 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2558 goto activate_failure;
2560 case GST_STATE_NULL:
2561 if (current == GST_STATE_READY)
2562 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2563 goto activate_failure;
2569 /* this flag is used to make the async state changes return immediately. We
2570 * don't want them to interfere with this state change */
2571 GST_OBJECT_LOCK (bin);
2572 bin->polling = TRUE;
2573 GST_OBJECT_UNLOCK (bin);
2575 /* iterate in state change order */
2576 it = gst_bin_iterate_sorted (bin);
2578 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2579 * Note how we don't reset this value when a resync happens, the reason being
2580 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2581 * even after a resync when the async element is gone */
2585 /* take base_time */
2586 base_time = gst_element_get_base_time (element);
2587 start_time = gst_element_get_start_time (element);
2589 have_no_preroll = FALSE;
2593 switch (gst_iterator_next (it, &data)) {
2594 case GST_ITERATOR_OK:
2598 child = g_value_get_object (&data);
2600 /* set state and base_time now */
2601 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2605 case GST_STATE_CHANGE_SUCCESS:
2606 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2607 "child '%s' changed state to %d(%s) successfully",
2608 GST_ELEMENT_NAME (child), next,
2609 gst_element_state_get_name (next));
2611 case GST_STATE_CHANGE_ASYNC:
2613 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2614 "child '%s' is changing state asynchronously to %s",
2615 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2619 case GST_STATE_CHANGE_FAILURE:{
2622 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2623 "child '%s' failed to go to state %d(%s)",
2624 GST_ELEMENT_NAME (child),
2625 next, gst_element_state_get_name (next));
2627 /* Only fail if the child is still inside
2628 * this bin. It might've been removed already
2629 * because of the error by the bin subclass
2630 * to ignore the error. */
2631 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2632 if (parent == GST_OBJECT_CAST (element)) {
2633 /* element is still in bin, really error now */
2634 gst_object_unref (parent);
2637 /* child removed from bin, let the resync code redo the state
2639 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2640 "child '%s' was removed from the bin",
2641 GST_ELEMENT_NAME (child));
2644 gst_object_unref (parent);
2648 case GST_STATE_CHANGE_NO_PREROLL:
2649 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2650 "child '%s' changed state to %d(%s) successfully without preroll",
2651 GST_ELEMENT_NAME (child), next,
2652 gst_element_state_get_name (next));
2653 have_no_preroll = TRUE;
2656 g_assert_not_reached ();
2659 g_value_reset (&data);
2662 case GST_ITERATOR_RESYNC:
2663 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
2664 gst_iterator_resync (it);
2667 case GST_ITERATOR_DONE:
2668 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
2674 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
2675 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
2678 if (have_no_preroll) {
2679 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2680 "we have NO_PREROLL elements %s -> NO_PREROLL",
2681 gst_element_state_change_return_get_name (ret));
2682 ret = GST_STATE_CHANGE_NO_PREROLL;
2683 } else if (have_async) {
2684 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2685 "we have ASYNC elements %s -> ASYNC",
2686 gst_element_state_change_return_get_name (ret));
2687 ret = GST_STATE_CHANGE_ASYNC;
2691 g_value_unset (&data);
2692 gst_iterator_free (it);
2694 GST_OBJECT_LOCK (bin);
2695 bin->polling = FALSE;
2696 /* it's possible that we did not get ASYNC from the children while the bin is
2697 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
2698 * itself as the source. In that case we still want to check if the state
2699 * change completed. */
2700 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
2701 /* no element returned ASYNC and there are no pending async_done messages,
2702 * we can just complete. */
2703 GST_DEBUG_OBJECT (bin, "no async elements");
2706 /* when we get here an ASYNC element was found */
2707 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
2708 /* we ignore ASYNC state changes when we go to READY or NULL */
2709 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
2710 gst_element_state_get_name (GST_STATE_TARGET (bin)));
2714 GST_DEBUG_OBJECT (bin, "check async elements");
2715 /* check if all elements managed to commit their state already */
2716 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
2717 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
2718 * all the elements commited their state while we were doing the state
2719 * change. We will still return ASYNC for consistency but we commit the
2720 * state already so that a _get_state() will return immediately. */
2721 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
2723 GST_DEBUG_OBJECT (bin, "async elements commited");
2724 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
2725 GST_CLOCK_TIME_NONE);
2729 bin->priv->pending_async_done = FALSE;
2730 GST_OBJECT_UNLOCK (bin);
2732 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2733 "done changing bin's state from %s to %s, now in %s, ret %s",
2734 gst_element_state_get_name (current),
2735 gst_element_state_get_name (next),
2736 gst_element_state_get_name (GST_STATE (element)),
2737 gst_element_state_change_return_get_name (ret));
2744 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
2745 "failure (de)activating src pads");
2746 return GST_STATE_CHANGE_FAILURE;
2751 * This function is a utility event handler for seek events.
2752 * It will send the event to all sinks or sources and appropriate
2753 * ghost pads depending on the event-direction.
2755 * Applications are free to override this behaviour and
2756 * implement their own seek handler, but this will work for
2757 * pretty much all cases in practice.
2760 gst_bin_send_event (GstElement * element, GstEvent * event)
2762 GstBin *bin = GST_BIN_CAST (element);
2764 gboolean res = TRUE;
2765 gboolean done = FALSE;
2766 GValue data = { 0, };
2768 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2769 iter = gst_bin_iterate_sources (bin);
2770 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
2771 GST_EVENT_TYPE_NAME (event));
2773 iter = gst_bin_iterate_sinks (bin);
2774 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
2775 GST_EVENT_TYPE_NAME (event));
2779 switch (gst_iterator_next (iter, &data)) {
2780 case GST_ITERATOR_OK:
2782 GstElement *child = g_value_get_object (&data);
2784 gst_event_ref (event);
2785 res &= gst_element_send_event (child, event);
2787 GST_LOG_OBJECT (child, "After handling %s event: %d",
2788 GST_EVENT_TYPE_NAME (event), res);
2790 g_value_reset (&data);
2793 case GST_ITERATOR_RESYNC:
2794 gst_iterator_resync (iter);
2797 case GST_ITERATOR_DONE:
2800 case GST_ITERATOR_ERROR:
2801 g_assert_not_reached ();
2805 g_value_unset (&data);
2806 gst_iterator_free (iter);
2808 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2809 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
2810 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
2811 GST_EVENT_TYPE_NAME (event));
2813 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
2814 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
2815 GST_EVENT_TYPE_NAME (event));
2820 switch (gst_iterator_next (iter, &data)) {
2821 case GST_ITERATOR_OK:
2823 GstPad *pad = g_value_get_object (&data);
2825 gst_event_ref (event);
2826 res &= gst_pad_send_event (pad, event);
2827 GST_LOG_OBJECT (pad, "After handling %s event: %d",
2828 GST_EVENT_TYPE_NAME (event), res);
2831 case GST_ITERATOR_RESYNC:
2832 gst_iterator_resync (iter);
2835 case GST_ITERATOR_DONE:
2838 case GST_ITERATOR_ERROR:
2839 g_assert_not_reached ();
2844 g_value_unset (&data);
2845 gst_iterator_free (iter);
2846 gst_event_unref (event);
2851 /* this is the function called by the threadpool. When async elements commit
2852 * their state, this function will attempt to bring the bin to the next state.
2855 gst_bin_continue_func (BinContinueData * data)
2858 GstState current, next, pending;
2859 GstStateChange transition;
2862 pending = data->pending;
2864 GST_DEBUG_OBJECT (bin, "waiting for state lock");
2865 GST_STATE_LOCK (bin);
2867 GST_DEBUG_OBJECT (bin, "doing state continue");
2868 GST_OBJECT_LOCK (bin);
2870 /* if a new state change happened after this thread was scheduled, we return
2872 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
2875 current = GST_STATE (bin);
2876 next = GST_STATE_GET_NEXT (current, pending);
2877 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
2879 GST_STATE_NEXT (bin) = next;
2880 GST_STATE_PENDING (bin) = pending;
2882 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
2883 GST_OBJECT_UNLOCK (bin);
2885 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
2886 "continue state change %s to %s, final %s",
2887 gst_element_state_get_name (current),
2888 gst_element_state_get_name (next), gst_element_state_get_name (pending));
2890 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
2892 GST_STATE_UNLOCK (bin);
2893 GST_DEBUG_OBJECT (bin, "state continue done");
2895 gst_object_unref (bin);
2896 g_slice_free (BinContinueData, data);
2901 GST_OBJECT_UNLOCK (bin);
2902 GST_STATE_UNLOCK (bin);
2903 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
2904 gst_object_unref (bin);
2905 g_slice_free (BinContinueData, data);
2910 static GstBusSyncReply
2911 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
2913 GstBinClass *bclass;
2915 bclass = GST_BIN_GET_CLASS (bin);
2916 if (bclass->handle_message)
2917 bclass->handle_message (bin, message);
2919 gst_message_unref (message);
2921 return GST_BUS_DROP;
2925 bin_push_state_continue (BinContinueData * data)
2932 klass = GST_BIN_GET_CLASS (bin);
2934 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
2935 g_thread_pool_push (klass->pool, data, NULL);
2938 /* an element started an async state change, if we were not busy with a state
2939 * change, we perform a lost state.
2940 * This function is called with the OBJECT lock.
2943 bin_handle_async_start (GstBin * bin)
2945 GstState old_state, new_state;
2947 GstMessage *amessage = NULL;
2949 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
2952 /* get our toplevel state */
2953 toplevel = BIN_IS_TOPLEVEL (bin);
2955 /* prepare an ASYNC_START message, we always post the start message even if we
2956 * are busy with a state change or when we are NO_PREROLL. */
2958 /* non toplevel bin, prepare async-start for the parent */
2959 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
2961 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
2964 /* async starts are ignored when we are NO_PREROLL */
2965 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
2966 goto was_no_preroll;
2968 old_state = GST_STATE (bin);
2970 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
2971 * PLAYING after optionally redistributing the base_time. */
2972 if (old_state > GST_STATE_PAUSED)
2973 new_state = GST_STATE_PAUSED;
2975 new_state = old_state;
2977 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2978 "lost state of %s, new %s", gst_element_state_get_name (old_state),
2979 gst_element_state_get_name (new_state));
2981 GST_STATE (bin) = new_state;
2982 GST_STATE_NEXT (bin) = new_state;
2983 GST_STATE_PENDING (bin) = new_state;
2984 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
2985 GST_OBJECT_UNLOCK (bin);
2988 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
2993 /* post our ASYNC_START. */
2994 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
2995 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
2997 GST_OBJECT_LOCK (bin);
3003 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3008 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3009 GST_OBJECT_UNLOCK (bin);
3014 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3015 GST_OBJECT_UNLOCK (bin);
3020 /* this function is called when there are no more async elements in the bin. We
3021 * post a state changed message and an ASYNC_DONE message.
3022 * This function is called with the OBJECT lock.
3025 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3026 gboolean flag_pending, GstClockTime running_time)
3028 GstState current, pending, target;
3029 GstStateChangeReturn old_ret;
3030 GstState old_state, old_next;
3031 gboolean toplevel, state_changed = FALSE;
3032 GstMessage *amessage = NULL;
3033 BinContinueData *cont = NULL;
3035 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3038 pending = GST_STATE_PENDING (bin);
3043 /* check if there is something to commit */
3044 if (pending == GST_STATE_VOID_PENDING)
3045 goto nothing_pending;
3047 old_ret = GST_STATE_RETURN (bin);
3048 GST_STATE_RETURN (bin) = ret;
3050 /* move to the next target state */
3051 target = GST_STATE_TARGET (bin);
3052 pending = GST_STATE_PENDING (bin) = target;
3054 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3056 old_state = GST_STATE (bin);
3057 /* this is the state we should go to next */
3058 old_next = GST_STATE_NEXT (bin);
3060 if (old_next != GST_STATE_PLAYING) {
3061 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3062 "committing state from %s to %s, old pending %s",
3063 gst_element_state_get_name (old_state),
3064 gst_element_state_get_name (old_next),
3065 gst_element_state_get_name (pending));
3067 /* update current state */
3068 current = GST_STATE (bin) = old_next;
3070 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3071 "setting state from %s to %s, pending %s",
3072 gst_element_state_get_name (old_state),
3073 gst_element_state_get_name (old_state),
3074 gst_element_state_get_name (pending));
3075 current = old_state;
3078 /* get our toplevel state */
3079 toplevel = BIN_IS_TOPLEVEL (bin);
3081 /* see if we reached the final state. If we are not toplevel, we also have to
3082 * stop here, the parent will continue our state. */
3083 if ((pending == current) || !toplevel) {
3084 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3085 "completed state change, pending VOID");
3087 /* mark VOID pending */
3088 pending = GST_STATE_VOID_PENDING;
3089 GST_STATE_PENDING (bin) = pending;
3090 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3092 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3093 "continue state change, pending %s",
3094 gst_element_state_get_name (pending));
3096 cont = g_slice_new (BinContinueData);
3098 /* ref to the bin */
3099 cont->bin = gst_object_ref (bin);
3100 /* cookie to detect concurrent state change */
3101 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3102 /* pending target state */
3103 cont->pending = pending;
3105 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3106 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3109 if (old_next != GST_STATE_PLAYING) {
3110 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3111 state_changed = TRUE;
3114 GST_OBJECT_UNLOCK (bin);
3116 if (state_changed) {
3117 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3121 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3122 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3123 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3126 GST_OBJECT_LOCK (bin);
3128 /* toplevel, start continue state */
3129 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3130 bin_push_state_continue (cont);
3132 GST_DEBUG_OBJECT (bin, "state change complete");
3133 GST_STATE_BROADCAST (bin);
3139 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3144 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3145 /* if we were busy with a state change and we are requested to flag a
3146 * pending async done, we do so here */
3148 bin->priv->pending_async_done = TRUE;
3153 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3159 bin_do_eos (GstBin * bin)
3164 GST_OBJECT_LOCK (bin);
3165 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3166 * we forward the EOS message to the parent bin or application
3168 eos = GST_STATE (bin) == GST_STATE_PLAYING
3169 && GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING
3170 && is_eos (bin, &seqnum);
3171 GST_OBJECT_UNLOCK (bin);
3174 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3176 GstMessage *tmessage;
3178 /* Clear out any further messages, and reset posted_eos so we can
3179 detect any new EOS that happens (eg, after a seek). Since all
3180 sinks have now posted an EOS, there will be no further EOS events
3181 seen unless there is a new logical EOS */
3182 GST_OBJECT_LOCK (bin);
3183 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3184 bin->priv->posted_eos = FALSE;
3185 GST_OBJECT_UNLOCK (bin);
3187 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3188 gst_message_set_seqnum (tmessage, seqnum);
3189 GST_DEBUG_OBJECT (bin,
3190 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3191 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3196 bin_do_stream_start (GstBin * bin)
3199 gboolean stream_start;
3201 GST_OBJECT_LOCK (bin);
3202 /* If all sinks are STREAM_START we forward the STREAM_START message
3203 * to the parent bin or application
3205 stream_start = is_stream_start (bin, &seqnum);
3206 GST_OBJECT_UNLOCK (bin);
3209 GstMessage *tmessage;
3211 GST_OBJECT_LOCK (bin);
3212 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3213 GST_OBJECT_UNLOCK (bin);
3215 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3216 gst_message_set_seqnum (tmessage, seqnum);
3217 GST_DEBUG_OBJECT (bin,
3218 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3220 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3224 /* must be called with the object lock. This function releases the lock to post
3227 bin_do_message_forward (GstBin * bin, GstMessage * message)
3229 if (bin->priv->message_forward) {
3230 GstMessage *forwarded;
3232 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3233 GST_MESSAGE_TYPE_NAME (message));
3234 GST_OBJECT_UNLOCK (bin);
3236 /* we need to convert these messages to element messages so that our parent
3237 * bin can easily ignore them and so that the application can easily
3238 * distinguish between the internally forwarded and the real messages. */
3239 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3240 gst_structure_new ("GstBinForwarded",
3241 "message", GST_TYPE_MESSAGE, message, NULL));
3243 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3245 GST_OBJECT_LOCK (bin);
3249 /* handle child messages:
3251 * This method is called synchronously when a child posts a message on
3254 * GST_MESSAGE_EOS: This message is only posted by sinks
3255 * in the PLAYING state. If all sinks posted the EOS message, post
3258 * GST_MESSAGE_STATE_DIRTY: Deprecated
3260 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3261 * element posts segment_start twice, only the last message is kept.
3263 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3264 * with the segment_done message. If there are no more segment_start
3265 * messages, post segment_done message upwards.
3267 * GST_MESSAGE_DURATION_CHANGED: clear any cached durations.
3268 * Whenever someone performs a duration query on the bin, we store the
3269 * result so we can answer it quicker the next time. Any element that
3270 * changes its duration marks our cached values invalid.
3271 * This message is also posted upwards. This is currently disabled
3272 * because too many elements don't post DURATION_CHANGED messages when
3273 * the duration changes.
3275 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3276 * can no longer provide a clock. The default bin behaviour is to
3277 * check if the lost clock was the one provided by the bin. If so and
3278 * we are currently in the PLAYING state, we forward the message to
3280 * This message is also generated when we remove a clock provider from
3281 * a bin. If this message is received by the application, it should
3282 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3283 * and a new base_time distribution.
3285 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3286 * can provide a clock. This mostly happens when we add a new clock
3287 * provider to the bin. The default behaviour of the bin is to mark the
3288 * currently selected clock as dirty, which will perform a clock
3289 * recalculation the next time we are asked to provide a clock.
3290 * This message is never sent to the application but is forwarded to
3293 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3294 * the state of the element and the fact that the element will need a
3295 * new base_time. This message is not forwarded to the application.
3297 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3298 * element when it posted ASYNC_START. If all elements are done, post a
3299 * ASYNC_DONE message to the parent.
3301 * OTHER: post upwards.
3304 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3307 GstMessageType type;
3308 GstMessage *tmessage;
3311 src = GST_MESSAGE_SRC (message);
3312 type = GST_MESSAGE_TYPE (message);
3314 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3315 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3316 GST_MESSAGE_TYPE_NAME (message));
3319 case GST_MESSAGE_ERROR:
3321 GST_OBJECT_LOCK (bin);
3323 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3324 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3325 GST_STATE_BROADCAST (bin);
3326 GST_OBJECT_UNLOCK (bin);
3330 case GST_MESSAGE_EOS:
3333 /* collect all eos messages from the children */
3334 GST_OBJECT_LOCK (bin);
3335 bin_do_message_forward (bin, message);
3336 /* ref message for future use */
3337 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3338 GST_OBJECT_UNLOCK (bin);
3343 case GST_MESSAGE_STREAM_START:
3346 /* collect all stream_start messages from the children */
3347 GST_OBJECT_LOCK (bin);
3348 /* ref message for future use */
3349 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3350 GST_OBJECT_UNLOCK (bin);
3352 bin_do_stream_start (bin);
3355 case GST_MESSAGE_STATE_DIRTY:
3357 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3360 gst_message_unref (message);
3363 case GST_MESSAGE_SEGMENT_START:{
3364 gboolean post = FALSE;
3368 gst_message_parse_segment_start (message, &format, &position);
3369 seqnum = gst_message_get_seqnum (message);
3371 GST_OBJECT_LOCK (bin);
3372 bin_do_message_forward (bin, message);
3373 /* if this is the first segment-start, post to parent but not to the
3375 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3376 (GST_OBJECT_PARENT (bin) != NULL)) {
3379 /* replace any previous segment_start message from this source
3380 * with the new segment start message */
3381 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3382 GST_OBJECT_UNLOCK (bin);
3384 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3386 gst_message_set_seqnum (tmessage, seqnum);
3388 /* post segment start with initial format and position. */
3389 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3391 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3395 case GST_MESSAGE_SEGMENT_DONE:
3397 gboolean post = FALSE;
3401 gst_message_parse_segment_done (message, &format, &position);
3402 seqnum = gst_message_get_seqnum (message);
3404 GST_OBJECT_LOCK (bin);
3405 bin_do_message_forward (bin, message);
3406 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3407 /* if there are no more segment_start messages, everybody posted
3408 * a segment_done and we can post one on the bus. */
3410 /* we don't care who still has a pending segment start */
3411 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3414 /* remove all old segment_done messages */
3415 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3417 GST_OBJECT_UNLOCK (bin);
3419 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3421 gst_message_set_seqnum (tmessage, seqnum);
3423 /* post segment done with latest format and position. */
3424 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3426 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3430 case GST_MESSAGE_DURATION_CHANGED:
3432 /* FIXME: remove all cached durations, next time somebody asks
3433 * for duration, we will recalculate. */
3435 GST_OBJECT_LOCK (bin);
3436 bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION_CHANGED);
3437 GST_OBJECT_UNLOCK (bin);
3441 case GST_MESSAGE_CLOCK_LOST:
3443 GstClock **provided_clock_p;
3444 GstElement **clock_provider_p;
3445 gboolean playing, provided, forward;
3448 gst_message_parse_clock_lost (message, &clock);
3450 GST_OBJECT_LOCK (bin);
3451 bin->clock_dirty = TRUE;
3452 /* if we lost the clock that we provided, post to parent but
3453 * only if we are PLAYING. */
3454 provided = (clock == bin->provided_clock);
3455 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3456 forward = playing & provided;
3458 GST_DEBUG_OBJECT (bin,
3459 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3460 bin->provided_clock, bin->clock_provider);
3461 provided_clock_p = &bin->provided_clock;
3462 clock_provider_p = &bin->clock_provider;
3463 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3464 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3466 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3467 provided, playing, forward);
3468 GST_OBJECT_UNLOCK (bin);
3474 gst_message_unref (message);
3477 case GST_MESSAGE_CLOCK_PROVIDE:
3481 GST_OBJECT_LOCK (bin);
3482 bin->clock_dirty = TRUE;
3483 /* a new clock is available, post to parent but not
3484 * to the application */
3485 forward = GST_OBJECT_PARENT (bin) != NULL;
3486 GST_OBJECT_UNLOCK (bin);
3492 gst_message_unref (message);
3495 case GST_MESSAGE_ASYNC_START:
3499 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3500 src ? GST_OBJECT_NAME (src) : "(NULL)");
3502 GST_OBJECT_LOCK (bin);
3503 bin_do_message_forward (bin, message);
3505 /* we ignore the message if we are going to <= READY */
3506 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3507 goto ignore_start_message;
3509 /* takes ownership of the message */
3510 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3512 bin_handle_async_start (bin);
3513 GST_OBJECT_UNLOCK (bin);
3516 ignore_start_message:
3518 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3519 gst_element_state_get_name (target));
3520 GST_OBJECT_UNLOCK (bin);
3521 gst_message_unref (message);
3525 case GST_MESSAGE_ASYNC_DONE:
3527 GstClockTime running_time;
3530 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3531 src ? GST_OBJECT_NAME (src) : "(NULL)");
3533 gst_message_parse_async_done (message, &running_time);
3535 GST_OBJECT_LOCK (bin);
3536 bin_do_message_forward (bin, message);
3538 /* ignore messages if we are shutting down */
3539 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3540 goto ignore_done_message;
3542 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3543 /* if there are no more ASYNC_START messages, everybody posted
3544 * a ASYNC_DONE and we can post one on the bus. When checking, we
3545 * don't care who still has a pending ASYNC_START */
3546 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3547 /* nothing found, remove all old ASYNC_DONE messages */
3548 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3550 GST_DEBUG_OBJECT (bin, "async elements commited");
3551 /* when we get an async done message when a state change was busy, we
3552 * need to set the pending_done flag so that at the end of the state
3553 * change we can see if we need to verify pending async elements, hence
3554 * the TRUE argument here. */
3555 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3558 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3560 GST_OBJECT_UNLOCK (bin);
3563 ignore_done_message:
3565 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3566 gst_element_state_get_name (target));
3567 GST_OBJECT_UNLOCK (bin);
3568 gst_message_unref (message);
3572 case GST_MESSAGE_STRUCTURE_CHANGE:
3576 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3578 GST_OBJECT_LOCK (bin);
3580 /* while the pad is busy, avoid following it when doing state changes.
3581 * Don't update the cookie yet, we will do that after the structure
3582 * change finished and we are ready to inspect the new updated
3584 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3587 /* a pad link/unlink ended, signal the state change iterator that we
3588 * need to resync by updating the structure_cookie. */
3589 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3590 GST_MESSAGE_STRUCTURE_CHANGE);
3591 if (!GST_BIN_IS_NO_RESYNC (bin))
3592 bin->priv->structure_cookie++;
3594 GST_OBJECT_UNLOCK (bin);
3597 gst_message_unref (message);
3608 /* Send all other messages upward */
3609 GST_DEBUG_OBJECT (bin, "posting message upward");
3610 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
3615 /* generic struct passed to all query fold methods */
3624 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
3625 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
3627 /* for duration/position we collect all durations/positions and take
3628 * the MAX of all valid results */
3630 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
3638 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3640 gboolean res = FALSE;
3641 GstObject *item = g_value_get_object (vitem);
3642 if (GST_IS_PAD (item))
3643 res = gst_pad_query (GST_PAD (item), fold->query);
3645 res = gst_element_query (GST_ELEMENT (item), fold->query);
3650 g_value_set_boolean (ret, TRUE);
3652 gst_query_parse_duration (fold->query, NULL, &duration);
3654 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
3656 if (duration == -1) {
3657 /* duration query succeeded, but duration is unknown */
3662 if (duration > fold->max)
3663 fold->max = duration;
3670 bin_query_duration_done (GstBin * bin, QueryFold * fold)
3674 gst_query_parse_duration (fold->query, &format, NULL);
3675 /* store max in query result */
3676 gst_query_set_duration (fold->query, format, fold->max);
3678 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
3680 /* FIXME: re-implement duration caching */
3683 GST_OBJECT_LOCK (bin);
3684 bin->messages = g_list_prepend (bin->messages,
3685 gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
3686 GST_OBJECT_UNLOCK (bin);
3691 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3693 gboolean res = FALSE;
3694 GstObject *item = g_value_get_object (vitem);
3695 if (GST_IS_PAD (item))
3696 res = gst_pad_query (GST_PAD (item), fold->query);
3698 res = gst_element_query (GST_ELEMENT (item), fold->query);
3703 g_value_set_boolean (ret, TRUE);
3705 gst_query_parse_position (fold->query, NULL, &position);
3707 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
3709 if (position > fold->max)
3710 fold->max = position;
3717 bin_query_position_done (GstBin * bin, QueryFold * fold)
3721 gst_query_parse_position (fold->query, &format, NULL);
3722 /* store max in query result */
3723 gst_query_set_position (fold->query, format, fold->max);
3725 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
3729 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3731 gboolean res = FALSE;
3732 GstObject *item = g_value_get_object (vitem);
3733 if (GST_IS_PAD (item))
3734 res = gst_pad_query (GST_PAD (item), fold->query);
3736 res = gst_element_query (GST_ELEMENT (item), fold->query);
3738 GstClockTime min, max;
3741 gst_query_parse_latency (fold->query, &live, &min, &max);
3743 GST_DEBUG_OBJECT (item,
3744 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3745 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
3747 /* for the combined latency we collect the MAX of all min latencies and
3748 * the MIN of all max latencies */
3750 if (min > fold->min)
3752 if (fold->max == -1)
3754 else if (max < fold->max)
3756 if (fold->live == FALSE)
3760 g_value_set_boolean (ret, FALSE);
3761 GST_DEBUG_OBJECT (item, "failed query");
3768 bin_query_latency_done (GstBin * bin, QueryFold * fold)
3770 /* store max in query result */
3771 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
3773 GST_DEBUG_OBJECT (bin,
3774 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3775 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
3779 /* generic fold, return first valid result */
3781 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3783 gboolean res = FALSE;
3784 GstObject *item = g_value_get_object (vitem);
3785 if (GST_IS_PAD (item))
3786 res = gst_pad_query (GST_PAD (item), fold->query);
3788 res = gst_element_query (GST_ELEMENT (item), fold->query);
3790 g_value_set_boolean (ret, TRUE);
3791 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
3794 /* and stop as soon as we have a valid result */
3798 /* Perform a query iteration for the given bin. The query is stored in
3799 * QueryFold and iter should be either a GstPad iterator or a
3800 * GstElement iterator. */
3802 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
3803 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
3804 QueryFold fold_data, gboolean default_return)
3806 gboolean res = default_return;
3808 /* set the result of the query to FALSE initially */
3809 g_value_init (&ret, G_TYPE_BOOLEAN);
3810 g_value_set_boolean (&ret, res);
3813 GstIteratorResult ires;
3815 ires = gst_iterator_fold (iter, fold_func, &ret, &fold_data);
3818 case GST_ITERATOR_RESYNC:
3819 gst_iterator_resync (iter);
3821 fold_init (bin, &fold_data);
3822 g_value_set_boolean (&ret, res);
3824 case GST_ITERATOR_OK:
3825 case GST_ITERATOR_DONE:
3826 res = g_value_get_boolean (&ret);
3827 if (fold_done != NULL && res)
3828 fold_done (bin, &fold_data);
3840 gst_bin_query (GstElement * element, GstQuery * query)
3842 GstBin *bin = GST_BIN_CAST (element);
3844 gboolean default_return = FALSE;
3845 gboolean res = FALSE;
3846 gboolean src_pads_query_result = FALSE;
3847 GstIteratorFoldFunction fold_func;
3848 QueryInitFunction fold_init = NULL;
3849 QueryDoneFunction fold_done = NULL;
3850 QueryFold fold_data;
3852 switch (GST_QUERY_TYPE (query)) {
3853 case GST_QUERY_DURATION:
3855 /* FIXME: implement duration caching in GstBin again */
3860 gst_query_parse_duration (query, &qformat, NULL);
3862 /* find cached duration query */
3863 GST_OBJECT_LOCK (bin);
3864 for (cached = bin->messages; cached; cached = g_list_next (cached)) {
3865 GstMessage *message = (GstMessage *) cached->data;
3867 if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION_CHANGED &&
3868 GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
3872 gst_message_parse_duration (message, &format, &duration);
3874 /* if cached same format, copy duration in query result */
3875 if (format == qformat) {
3876 GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
3878 GST_OBJECT_UNLOCK (bin);
3880 gst_query_set_duration (query, qformat, duration);
3886 GST_OBJECT_UNLOCK (bin);
3888 GST_FIXME ("implement duration caching in GstBin again");
3890 /* no cached value found, iterate and collect durations */
3891 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
3892 fold_init = bin_query_min_max_init;
3893 fold_done = bin_query_duration_done;
3896 case GST_QUERY_POSITION:
3898 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
3899 fold_init = bin_query_min_max_init;
3900 fold_done = bin_query_position_done;
3903 case GST_QUERY_LATENCY:
3905 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
3906 fold_init = bin_query_min_max_init;
3907 fold_done = bin_query_latency_done;
3908 default_return = TRUE;
3912 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
3916 fold_data.query = query;
3918 iter = gst_bin_iterate_sinks (bin);
3919 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
3920 query, GST_QUERY_TYPE_NAME (query));
3923 fold_init (bin, &fold_data);
3926 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, fold_data,
3928 gst_iterator_free (iter);
3931 /* Query the source pads of the element */
3932 iter = gst_element_iterate_src_pads (element);
3933 src_pads_query_result =
3934 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
3935 fold_data, default_return);
3936 gst_iterator_free (iter);
3938 if (src_pads_query_result)
3942 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
3948 set_context (const GValue * item, gpointer user_data)
3950 GstElement *element = g_value_get_object (item);
3952 gst_element_set_context (element, user_data);
3956 gst_bin_set_context (GstElement * element, GstContext * context)
3959 GstIterator *children;
3961 g_return_if_fail (GST_IS_BIN (element));
3963 bin = GST_BIN (element);
3965 children = gst_bin_iterate_elements (bin);
3966 while (gst_iterator_foreach (children, set_context,
3967 context) == GST_ITERATOR_RESYNC);
3968 gst_iterator_free (children);
3969 GST_OBJECT_LOCK (bin);
3970 gst_context_replace (&bin->priv->context, context);
3971 GST_OBJECT_UNLOCK (bin);
3975 compare_name (const GValue * velement, const gchar * name)
3978 GstElement *element = g_value_get_object (velement);
3980 GST_OBJECT_LOCK (element);
3981 eq = strcmp (GST_ELEMENT_NAME (element), name);
3982 GST_OBJECT_UNLOCK (element);
3988 * gst_bin_get_by_name:
3990 * @name: the element name to search for
3992 * Gets the element with the given name from a bin. This
3993 * function recurses into child bins.
3995 * Returns NULL if no element with the given name is found in the bin.
3997 * MT safe. Caller owns returned reference.
3999 * Returns: (transfer full): the #GstElement with the given name, or NULL
4002 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4004 GstIterator *children;
4005 GValue result = { 0, };
4006 GstElement *element;
4009 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4011 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4012 GST_ELEMENT_NAME (bin), name);
4014 children = gst_bin_iterate_recurse (bin);
4015 found = gst_iterator_find_custom (children,
4016 (GCompareFunc) compare_name, &result, (gpointer) name);
4017 gst_iterator_free (children);
4020 element = g_value_dup_object (&result);
4021 g_value_unset (&result);
4030 * gst_bin_get_by_name_recurse_up:
4032 * @name: the element name to search for
4034 * Gets the element with the given name from this bin. If the
4035 * element is not found, a recursion is performed on the parent bin.
4038 * - no element with the given name is found in the bin
4040 * MT safe. Caller owns returned reference.
4042 * Returns: (transfer full): the #GstElement with the given name, or NULL
4045 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4049 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4050 g_return_val_if_fail (name != NULL, NULL);
4052 result = gst_bin_get_by_name (bin, name);
4057 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4059 if (GST_IS_BIN (parent)) {
4060 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4062 gst_object_unref (parent);
4070 compare_interface (const GValue * velement, GValue * interface)
4072 GstElement *element = g_value_get_object (velement);
4073 GType interface_type = (GType) g_value_get_pointer (interface);
4076 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4085 * gst_bin_get_by_interface:
4087 * @iface: the #GType of an interface
4089 * Looks for an element inside the bin that implements the given
4090 * interface. If such an element is found, it returns the element.
4091 * You can cast this element to the given interface afterwards. If you want
4092 * all elements that implement the interface, use
4093 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4095 * MT safe. Caller owns returned reference.
4097 * Returns: (transfer full): A #GstElement inside the bin implementing the interface
4100 gst_bin_get_by_interface (GstBin * bin, GType iface)
4102 GstIterator *children;
4103 GValue result = { 0, };
4104 GstElement *element;
4106 GValue viface = { 0, };
4108 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4109 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4111 g_value_init (&viface, G_TYPE_POINTER);
4112 g_value_set_pointer (&viface, (gpointer) iface);
4114 children = gst_bin_iterate_recurse (bin);
4115 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4117 gst_iterator_free (children);
4120 element = g_value_dup_object (&result);
4121 g_value_unset (&result);
4125 g_value_unset (&viface);
4131 * gst_bin_iterate_all_by_interface:
4133 * @iface: the #GType of an interface
4135 * Looks for all elements inside the bin that implements the given
4136 * interface. You can safely cast all returned elements to the given interface.
4137 * The function recurses inside child bins. The iterator will yield a series
4138 * of #GstElement that should be unreffed after use.
4140 * MT safe. Caller owns returned value.
4142 * Returns: (transfer full): a #GstIterator of #GstElement for all elements
4143 * in the bin implementing the given interface, or NULL
4146 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4148 GstIterator *children;
4149 GstIterator *result;
4150 GValue viface = { 0, };
4152 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4153 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4155 g_value_init (&viface, G_TYPE_POINTER);
4156 g_value_set_pointer (&viface, (gpointer) iface);
4158 children = gst_bin_iterate_recurse (bin);
4159 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4162 g_value_unset (&viface);