2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
4 * 2005 Wim Taymans <wim@fluendo.com>
6 * gstobject.c: Fundamental class used for all of GStreamer
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.
27 * @short_description: Base class for the GStreamer object hierarchy
29 * #GstObject provides a root for the object hierarchy tree filed in by the
30 * GStreamer library. It is currently a thin wrapper on top of
31 * #GInitiallyUnowned. It is an abstract class that is not very usable on its own.
33 * #GstObject gives us basic refcounting, parenting functionality and locking.
34 * Most of the functions are just extended for special GStreamer needs and can be
35 * found under the same name in the base class of #GstObject which is #GObject
36 * (e.g. g_object_ref() becomes gst_object_ref()).
38 * Since #GstObject derives from #GInitiallyUnowned, it also inherits the
39 * floating reference. Be aware that functions such as gst_bin_add() and
40 * gst_element_add_pad() take ownership of the floating reference.
42 * In contrast to #GObject instances, #GstObject adds a name property. The functions
43 * gst_object_set_name() and gst_object_get_name() are used to set/get the name
46 * ## controlled properties
48 * Controlled properties offers a lightweight way to adjust gobject properties
49 * over stream-time. It works by using time-stamped value pairs that are queued
50 * for element-properties. At run-time the elements continuously pull value
51 * changes for the current stream-time.
53 * What needs to be changed in a #GstElement?
54 * Very little - it is just two steps to make a plugin controllable!
56 * * mark gobject-properties paramspecs that make sense to be controlled,
57 * by GST_PARAM_CONTROLLABLE.
59 * * when processing data (get, chain, loop function) at the beginning call
60 * gst_object_sync_values(element,timestamp).
61 * This will make the controller update all GObject properties that are
62 * under its control with the current values based on the timestamp.
64 * What needs to be done in applications? Again it's not a lot to change.
66 * * create a #GstControlSource.
67 * csource = gst_interpolation_control_source_new ();
68 * g_object_set (csource, "mode", GST_INTERPOLATION_MODE_LINEAR, NULL);
70 * * Attach the #GstControlSource on the controller to a property.
71 * gst_object_add_control_binding (object, gst_direct_control_binding_new (object, "prop1", csource));
73 * * Set the control values
74 * gst_timed_value_control_source_set ((GstTimedValueControlSource *)csource,0 * GST_SECOND, value1);
75 * gst_timed_value_control_source_set ((GstTimedValueControlSource *)csource,1 * GST_SECOND, value2);
77 * * start your pipeline
80 #include "gst_private.h"
81 #include "glib-compat-private.h"
83 #include "gstobject.h"
85 #include "gstcontrolbinding.h"
86 #include "gstcontrolsource.h"
88 #include "gstparamspecs.h"
91 #define DEBUG_REFCOUNT
93 /* Object signals and args */
114 /* maps type name quark => count */
115 static GData *object_name_counts = NULL;
117 G_LOCK_DEFINE_STATIC (object_name_mutex);
119 static void gst_object_set_property (GObject * object, guint prop_id,
120 const GValue * value, GParamSpec * pspec);
121 static void gst_object_get_property (GObject * object, guint prop_id,
122 GValue * value, GParamSpec * pspec);
124 static void gst_object_dispatch_properties_changed (GObject * object,
125 guint n_pspecs, GParamSpec ** pspecs);
127 static void gst_object_dispose (GObject * object);
128 static void gst_object_finalize (GObject * object);
130 static gboolean gst_object_set_name_default (GstObject * object);
132 static guint gst_object_signals[LAST_SIGNAL] = { 0 };
134 static GParamSpec *properties[PROP_LAST];
136 G_DEFINE_ABSTRACT_TYPE (GstObject, gst_object, G_TYPE_INITIALLY_UNOWNED);
139 gst_object_constructed (GObject * object)
141 GST_TRACER_OBJECT_CREATED (GST_OBJECT_CAST (object));
143 ((GObjectClass *) gst_object_parent_class)->constructed (object);
147 gst_object_class_init (GstObjectClass * klass)
149 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
151 gobject_class->set_property = gst_object_set_property;
152 gobject_class->get_property = gst_object_get_property;
154 properties[PROP_NAME] =
155 g_param_spec_string ("name", "Name", "The name of the object", NULL,
156 G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
161 * The parent of the object. Please note, that when changing the 'parent'
162 * property, we don't emit #GObject::notify and #GstObject::deep-notify
163 * signals due to locking issues. In some cases one can use
164 * #GstBin::element-added or #GstBin::element-removed signals on the parent to
165 * achieve a similar effect.
167 properties[PROP_PARENT] =
168 g_param_spec_object ("parent", "Parent", "The parent of the object",
169 GST_TYPE_OBJECT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
171 g_object_class_install_properties (gobject_class, PROP_LAST, properties);
174 * GstObject::deep-notify:
175 * @gstobject: a #GstObject
176 * @prop_object: the object that originated the signal
177 * @prop: the property that changed
179 * The deep notify signal is used to be notified of property changes. It is
180 * typically attached to the toplevel bin to receive notifications from all
181 * the elements contained in that bin.
183 gst_object_signals[DEEP_NOTIFY] =
184 g_signal_new ("deep-notify", G_TYPE_FROM_CLASS (klass),
185 G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE | G_SIGNAL_DETAILED |
186 G_SIGNAL_NO_HOOKS, G_STRUCT_OFFSET (GstObjectClass, deep_notify), NULL,
187 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 2, GST_TYPE_OBJECT,
190 klass->path_string_separator = "/";
192 /* see the comments at gst_object_dispatch_properties_changed */
193 gobject_class->dispatch_properties_changed
194 = GST_DEBUG_FUNCPTR (gst_object_dispatch_properties_changed);
196 gobject_class->constructed = gst_object_constructed;
197 gobject_class->dispose = gst_object_dispose;
198 gobject_class->finalize = gst_object_finalize;
202 gst_object_init (GstObject * object)
204 g_mutex_init (&object->lock);
205 object->parent = NULL;
207 GST_CAT_TRACE_OBJECT (GST_CAT_REFCOUNTING, object, "%p new", object);
211 object->control_rate = 100 * GST_MSECOND;
212 object->last_sync = GST_CLOCK_TIME_NONE;
217 * @object: (type Gst.Object): a #GstObject to reference
219 * Increments the reference count on @object. This function
220 * does not take the lock on @object because it relies on
221 * atomic refcounting.
223 * This object returns the input parameter to ease writing
225 * result = gst_object_ref (object->parent);
227 * Returns: (transfer full) (type Gst.Object): A pointer to @object
230 gst_object_ref (gpointer object)
232 g_return_val_if_fail (object != NULL, NULL);
234 GST_TRACER_OBJECT_REFFED (object, ((GObject *) object)->ref_count + 1);
235 #ifdef DEBUG_REFCOUNT
236 GST_CAT_TRACE_OBJECT (GST_CAT_REFCOUNTING, object, "%p ref %d->%d", object,
237 ((GObject *) object)->ref_count, ((GObject *) object)->ref_count + 1);
239 g_object_ref (object);
246 * @object: (type Gst.Object): a #GstObject to unreference
248 * Decrements the reference count on @object. If reference count hits
249 * zero, destroy @object. This function does not take the lock
250 * on @object as it relies on atomic refcounting.
252 * The unref method should never be called with the LOCK held since
253 * this might deadlock the dispose function.
256 gst_object_unref (gpointer object)
258 g_return_if_fail (object != NULL);
259 g_return_if_fail (((GObject *) object)->ref_count > 0);
261 GST_TRACER_OBJECT_UNREFFED (object, ((GObject *) object)->ref_count - 1);
262 #ifdef DEBUG_REFCOUNT
263 GST_CAT_TRACE_OBJECT (GST_CAT_REFCOUNTING, object, "%p unref %d->%d", object,
264 ((GObject *) object)->ref_count, ((GObject *) object)->ref_count - 1);
266 g_object_unref (object);
270 * gst_object_ref_sink: (skip)
271 * @object: a #GstObject to sink
273 * Increase the reference count of @object, and possibly remove the floating
274 * reference, if @object has a floating reference.
276 * In other words, if the object is floating, then this call "assumes ownership"
277 * of the floating reference, converting it to a normal reference by clearing
278 * the floating flag while leaving the reference count unchanged. If the object
279 * is not floating, then this call adds a new normal reference increasing the
280 * reference count by one.
283 gst_object_ref_sink (gpointer object)
285 g_return_val_if_fail (object != NULL, NULL);
287 #ifdef DEBUG_REFCOUNT
288 GST_CAT_TRACE_OBJECT (GST_CAT_REFCOUNTING, object, "%p ref_sink %d->%d",
289 object, ((GObject *) object)->ref_count,
290 ((GObject *) object)->ref_count + 1);
292 return g_object_ref_sink (object);
296 * gst_object_replace:
297 * @oldobj: (inout) (transfer full) (nullable): pointer to a place of
298 * a #GstObject to replace
299 * @newobj: (transfer none) (allow-none): a new #GstObject
301 * Atomically modifies a pointer to point to a new object.
302 * The reference count of @oldobj is decreased and the reference count of
303 * @newobj is increased.
305 * Either @newobj and the value pointed to by @oldobj may be %NULL.
307 * Returns: %TRUE if @newobj was different from @oldobj
310 gst_object_replace (GstObject ** oldobj, GstObject * newobj)
314 g_return_val_if_fail (oldobj != NULL, FALSE);
316 #ifdef DEBUG_REFCOUNT
317 GST_CAT_TRACE (GST_CAT_REFCOUNTING, "replace %p %s (%d) with %p %s (%d)",
318 *oldobj, *oldobj ? GST_STR_NULL (GST_OBJECT_NAME (*oldobj)) : "(NONE)",
319 *oldobj ? G_OBJECT (*oldobj)->ref_count : 0,
320 newobj, newobj ? GST_STR_NULL (GST_OBJECT_NAME (newobj)) : "(NONE)",
321 newobj ? G_OBJECT (newobj)->ref_count : 0);
324 oldptr = g_atomic_pointer_get ((gpointer *) oldobj);
326 if (G_UNLIKELY (oldptr == newobj))
330 gst_object_ref (newobj);
332 while (G_UNLIKELY (!g_atomic_pointer_compare_and_exchange ((gpointer *)
333 oldobj, oldptr, newobj))) {
334 oldptr = g_atomic_pointer_get ((gpointer *) oldobj);
335 if (G_UNLIKELY (oldptr == newobj))
340 gst_object_unref (oldptr);
342 return oldptr != newobj;
345 /* dispose is called when the object has to release all links
346 * to other objects */
348 gst_object_dispose (GObject * object)
350 GstObject *self = (GstObject *) object;
353 GST_CAT_TRACE_OBJECT (GST_CAT_REFCOUNTING, object, "%p dispose", object);
355 GST_OBJECT_LOCK (object);
356 if ((parent = GST_OBJECT_PARENT (object)))
358 GST_OBJECT_PARENT (object) = NULL;
359 GST_OBJECT_UNLOCK (object);
361 if (self->control_bindings) {
364 for (node = self->control_bindings; node; node = g_list_next (node)) {
365 gst_object_unparent (node->data);
367 g_list_free (self->control_bindings);
368 self->control_bindings = NULL;
371 ((GObjectClass *) gst_object_parent_class)->dispose (object);
378 g_critical ("\nTrying to dispose object \"%s\", but it still has a "
379 "parent \"%s\".\nYou need to let the parent manage the "
380 "object instead of unreffing the object directly.\n",
381 GST_OBJECT_NAME (object), GST_OBJECT_NAME (parent));
382 GST_OBJECT_UNLOCK (object);
383 /* ref the object again to revive it in this error case */
384 gst_object_ref (object);
389 /* finalize is called when the object has to free its resources */
391 gst_object_finalize (GObject * object)
393 GstObject *gstobject = GST_OBJECT_CAST (object);
395 GST_CAT_TRACE_OBJECT (GST_CAT_REFCOUNTING, object, "%p finalize", object);
397 g_signal_handlers_destroy (object);
399 g_free (gstobject->name);
400 g_mutex_clear (&gstobject->lock);
402 GST_TRACER_OBJECT_DESTROYED (gstobject);
404 ((GObjectClass *) gst_object_parent_class)->finalize (object);
407 /* Changing a GObject property of a GstObject will result in "deep-notify"
408 * signals being emitted by the object itself, as well as in each parent
409 * object. This is so that an application can connect a listener to the
410 * top-level bin to catch property-change notifications for all contained
416 gst_object_dispatch_properties_changed (GObject * object,
417 guint n_pspecs, GParamSpec ** pspecs)
419 GstObject *gst_object, *parent, *old_parent;
421 #ifndef GST_DISABLE_GST_DEBUG
423 const gchar *debug_name;
426 /* do the standard dispatching */
428 gst_object_parent_class)->dispatch_properties_changed (object, n_pspecs,
431 gst_object = GST_OBJECT_CAST (object);
432 #ifndef GST_DISABLE_GST_DEBUG
433 if (G_UNLIKELY (_gst_debug_min >= GST_LEVEL_LOG)) {
434 name = gst_object_get_name (gst_object);
435 debug_name = GST_STR_NULL (name);
440 /* now let the parent dispatch those, too */
441 parent = gst_object_get_parent (gst_object);
443 for (i = 0; i < n_pspecs; i++) {
444 GST_CAT_LOG_OBJECT (GST_CAT_PROPERTIES, parent,
445 "deep notification from %s (%s)", debug_name, pspecs[i]->name);
447 g_signal_emit (parent, gst_object_signals[DEEP_NOTIFY],
448 g_quark_from_string (pspecs[i]->name), gst_object, pspecs[i]);
452 parent = gst_object_get_parent (old_parent);
453 gst_object_unref (old_parent);
455 #ifndef GST_DISABLE_GST_DEBUG
461 * gst_object_default_deep_notify:
462 * @object: the #GObject that signalled the notify.
463 * @orig: a #GstObject that initiated the notify.
464 * @pspec: a #GParamSpec of the property.
465 * @excluded_props: (array zero-terminated=1) (element-type gchar*) (allow-none):
466 * a set of user-specified properties to exclude or %NULL to show
469 * A default deep_notify signal callback for an object. The user data
470 * should contain a pointer to an array of strings that should be excluded
471 * from the notify. The default handler will print the new value of the property
474 * MT safe. This function grabs and releases @object's LOCK for getting its
478 gst_object_default_deep_notify (GObject * object, GstObject * orig,
479 GParamSpec * pspec, gchar ** excluded_props)
481 GValue value = { 0, }; /* the important thing is that value.type = 0 */
485 if (pspec->flags & G_PARAM_READABLE) {
486 /* let's not print these out for excluded properties... */
487 while (excluded_props != NULL && *excluded_props != NULL) {
488 if (strcmp (pspec->name, *excluded_props) == 0)
492 g_value_init (&value, pspec->value_type);
493 g_object_get_property (G_OBJECT (orig), pspec->name, &value);
495 if (G_VALUE_HOLDS_STRING (&value))
496 str = g_value_dup_string (&value);
498 str = gst_value_serialize (&value);
499 name = gst_object_get_path_string (orig);
500 g_print ("%s: %s = %s\n", name, pspec->name, str);
503 g_value_unset (&value);
505 name = gst_object_get_path_string (orig);
506 g_warning ("Parameter %s not readable in %s.", pspec->name, name);
512 gst_object_set_name_default (GstObject * object)
514 const gchar *type_name;
520 /* to ensure guaranteed uniqueness across threads, only one thread
521 * may ever assign a name */
522 G_LOCK (object_name_mutex);
524 if (!object_name_counts) {
525 g_datalist_init (&object_name_counts);
528 q = g_type_qname (G_OBJECT_TYPE (object));
529 count = GPOINTER_TO_INT (g_datalist_id_get_data (&object_name_counts, q));
530 g_datalist_id_set_data (&object_name_counts, q, GINT_TO_POINTER (count + 1));
532 G_UNLOCK (object_name_mutex);
534 /* GstFooSink -> foosink<N> */
535 type_name = g_quark_to_string (q);
536 if (strncmp (type_name, "Gst", 3) == 0)
538 /* give the 20th "queue" element and the first "queue2" different names */
539 l = strlen (type_name);
540 if (l > 0 && g_ascii_isdigit (type_name[l - 1])) {
541 name = g_strdup_printf ("%s-%d", type_name, count);
543 name = g_strdup_printf ("%s%d", type_name, count);
547 for (i = 0; i < l; i++)
548 name[i] = g_ascii_tolower (name[i]);
550 GST_OBJECT_LOCK (object);
551 if (G_UNLIKELY (object->parent != NULL))
554 g_free (object->name);
557 GST_OBJECT_UNLOCK (object);
564 GST_WARNING ("parented objects can't be renamed");
565 GST_OBJECT_UNLOCK (object);
571 * gst_object_set_name:
572 * @object: a #GstObject
573 * @name: (allow-none): new name of object
575 * Sets the name of @object, or gives @object a guaranteed unique
576 * name (if @name is %NULL).
577 * This function makes a copy of the provided name, so the caller
578 * retains ownership of the name it sent.
580 * Returns: %TRUE if the name could be set. Since Objects that have
581 * a parent cannot be renamed, this function returns %FALSE in those
584 * MT safe. This function grabs and releases @object's LOCK.
587 gst_object_set_name (GstObject * object, const gchar * name)
591 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
593 GST_OBJECT_LOCK (object);
595 /* parented objects cannot be renamed */
596 if (G_UNLIKELY (object->parent != NULL))
600 g_free (object->name);
601 object->name = g_strdup (name);
602 GST_OBJECT_UNLOCK (object);
605 GST_OBJECT_UNLOCK (object);
606 result = gst_object_set_name_default (object);
609 g_object_notify (G_OBJECT (object), "name");
615 GST_WARNING ("parented objects can't be renamed");
616 GST_OBJECT_UNLOCK (object);
622 * gst_object_get_name:
623 * @object: a #GstObject
625 * Returns a copy of the name of @object.
626 * Caller should g_free() the return value after usage.
627 * For a nameless object, this returns %NULL, which you can safely g_free()
630 * Free-function: g_free
632 * Returns: (transfer full) (nullable): the name of @object. g_free()
635 * MT safe. This function grabs and releases @object's LOCK.
638 gst_object_get_name (GstObject * object)
640 gchar *result = NULL;
642 g_return_val_if_fail (GST_IS_OBJECT (object), NULL);
644 GST_OBJECT_LOCK (object);
645 result = g_strdup (object->name);
646 GST_OBJECT_UNLOCK (object);
652 * gst_object_set_parent:
653 * @object: (transfer floating): a #GstObject
654 * @parent: new parent of object
656 * Sets the parent of @object to @parent. The object's reference count will
657 * be incremented, and any floating reference will be removed (see gst_object_ref_sink()).
659 * Returns: %TRUE if @parent could be set or %FALSE when @object
660 * already had a parent or @object and @parent are the same.
662 * MT safe. Grabs and releases @object's LOCK.
665 gst_object_set_parent (GstObject * object, GstObject * parent)
667 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
668 g_return_val_if_fail (GST_IS_OBJECT (parent), FALSE);
669 g_return_val_if_fail (object != parent, FALSE);
671 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object,
672 "set parent (ref and sink)");
674 GST_OBJECT_LOCK (object);
675 if (G_UNLIKELY (object->parent != NULL))
678 object->parent = parent;
679 gst_object_ref_sink (object);
680 GST_OBJECT_UNLOCK (object);
682 /* FIXME-2.0: this does not work, the deep notify takes the lock from the
683 * parent object and deadlocks when the parent holds its lock when calling
684 * this function (like _element_add_pad()), we need to use a GRecMutex
685 * for locking the parent instead.
687 /* g_object_notify_by_pspec ((GObject *)object, properties[PROP_PARENT]); */
694 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object,
695 "set parent failed, object already had a parent");
696 gst_object_ref_sink (object);
697 gst_object_unref (object);
698 GST_OBJECT_UNLOCK (object);
704 * gst_object_get_parent:
705 * @object: a #GstObject
707 * Returns the parent of @object. This function increases the refcount
708 * of the parent object so you should gst_object_unref() it after usage.
710 * Returns: (transfer full) (nullable): parent of @object, this can be
711 * %NULL if @object has no parent. unref after usage.
713 * MT safe. Grabs and releases @object's LOCK.
716 gst_object_get_parent (GstObject * object)
718 GstObject *result = NULL;
720 g_return_val_if_fail (GST_IS_OBJECT (object), NULL);
722 GST_OBJECT_LOCK (object);
723 result = object->parent;
724 if (G_LIKELY (result))
725 gst_object_ref (result);
726 GST_OBJECT_UNLOCK (object);
732 * gst_object_unparent:
733 * @object: a #GstObject to unparent
735 * Clear the parent of @object, removing the associated reference.
736 * This function decreases the refcount of @object.
738 * MT safe. Grabs and releases @object's lock.
741 gst_object_unparent (GstObject * object)
745 g_return_if_fail (GST_IS_OBJECT (object));
747 GST_OBJECT_LOCK (object);
748 parent = object->parent;
750 if (G_LIKELY (parent != NULL)) {
751 GST_CAT_TRACE_OBJECT (GST_CAT_REFCOUNTING, object, "unparent");
752 object->parent = NULL;
753 GST_OBJECT_UNLOCK (object);
755 /* g_object_notify_by_pspec ((GObject *)object, properties[PROP_PARENT]); */
757 gst_object_unref (object);
759 GST_OBJECT_UNLOCK (object);
764 * gst_object_has_as_parent:
765 * @object: a #GstObject to check
766 * @parent: a #GstObject to check as parent
768 * Check if @parent is the parent of @object.
769 * E.g. a #GstElement can check if it owns a given #GstPad.
771 * Returns: %FALSE if either @object or @parent is %NULL. %TRUE if @parent is
772 * the parent of @object. Otherwise %FALSE.
774 * MT safe. Grabs and releases @object's locks.
778 gst_object_has_as_parent (GstObject * object, GstObject * parent)
780 gboolean result = FALSE;
782 if (G_LIKELY (GST_IS_OBJECT (object) && GST_IS_OBJECT (parent))) {
783 GST_OBJECT_LOCK (object);
784 result = GST_OBJECT_PARENT (object) == parent;
785 GST_OBJECT_UNLOCK (object);
792 * gst_object_has_as_ancestor:
793 * @object: a #GstObject to check
794 * @ancestor: a #GstObject to check as ancestor
796 * Check if @object has an ancestor @ancestor somewhere up in
797 * the hierarchy. One can e.g. check if a #GstElement is inside a #GstPipeline.
799 * Returns: %TRUE if @ancestor is an ancestor of @object.
801 * MT safe. Grabs and releases @object's locks.
804 gst_object_has_as_ancestor (GstObject * object, GstObject * ancestor)
806 GstObject *parent, *tmp;
808 if (!ancestor || !object)
811 parent = gst_object_ref (object);
813 if (parent == ancestor) {
814 gst_object_unref (parent);
818 tmp = gst_object_get_parent (parent);
819 gst_object_unref (parent);
827 * gst_object_has_ancestor:
828 * @object: a #GstObject to check
829 * @ancestor: a #GstObject to check as ancestor
831 * Check if @object has an ancestor @ancestor somewhere up in
832 * the hierarchy. One can e.g. check if a #GstElement is inside a #GstPipeline.
834 * Returns: %TRUE if @ancestor is an ancestor of @object.
836 * Deprecated: Use gst_object_has_as_ancestor() instead.
838 * MT safe. Grabs and releases @object's locks.
840 #ifndef GST_REMOVE_DEPRECATED
842 gst_object_has_ancestor (GstObject * object, GstObject * ancestor)
844 return gst_object_has_as_ancestor (object, ancestor);
849 * gst_object_check_uniqueness:
850 * @list: (transfer none) (element-type Gst.Object): a list of #GstObject to
852 * @name: the name to search for
854 * Checks to see if there is any object named @name in @list. This function
855 * does not do any locking of any kind. You might want to protect the
856 * provided list with the lock of the owner of the list. This function
857 * will lock each #GstObject in the list to compare the name, so be
858 * careful when passing a list with a locked object.
860 * Returns: %TRUE if a #GstObject named @name does not appear in @list,
863 * MT safe. Grabs and releases the LOCK of each object in the list.
866 gst_object_check_uniqueness (GList * list, const gchar * name)
868 gboolean result = TRUE;
870 g_return_val_if_fail (name != NULL, FALSE);
872 for (; list; list = g_list_next (list)) {
876 child = GST_OBJECT_CAST (list->data);
878 GST_OBJECT_LOCK (child);
879 eq = strcmp (GST_OBJECT_NAME (child), name) == 0;
880 GST_OBJECT_UNLOCK (child);
882 if (G_UNLIKELY (eq)) {
892 gst_object_set_property (GObject * object, guint prop_id,
893 const GValue * value, GParamSpec * pspec)
895 GstObject *gstobject;
897 gstobject = GST_OBJECT_CAST (object);
901 gst_object_set_name (gstobject, g_value_get_string (value));
904 gst_object_set_parent (gstobject, g_value_get_object (value));
907 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
913 gst_object_get_property (GObject * object, guint prop_id,
914 GValue * value, GParamSpec * pspec)
916 GstObject *gstobject;
918 gstobject = GST_OBJECT_CAST (object);
922 g_value_take_string (value, gst_object_get_name (gstobject));
925 g_value_take_object (value, gst_object_get_parent (gstobject));
928 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
934 * gst_object_get_path_string:
935 * @object: a #GstObject
937 * Generates a string describing the path of @object in
938 * the object hierarchy. Only useful (or used) for debugging.
940 * Free-function: g_free
942 * Returns: (transfer full): a string describing the path of @object. You must
943 * g_free() the string after usage.
945 * MT safe. Grabs and releases the #GstObject's LOCK for all objects
949 gst_object_get_path_string (GstObject * object)
954 gchar *prevpath, *path;
955 const gchar *typename;
957 const gchar *separator;
959 /* ref object before adding to list */
960 gst_object_ref (object);
961 parentage = g_slist_prepend (NULL, object);
963 path = g_strdup ("");
965 /* first walk the object hierarchy to build a list of the parents,
966 * be careful here with refcounting. */
968 if (GST_IS_OBJECT (object)) {
969 parent = gst_object_get_parent (object);
970 /* add parents to list, refcount remains increased while
971 * we handle the object */
973 parentage = g_slist_prepend (parentage, parent);
978 } while (object != NULL);
980 /* then walk the parent list and print them out. we need to
981 * decrease the refcounting on each element after we handled
983 for (parents = parentage; parents; parents = g_slist_next (parents)) {
984 if (G_IS_OBJECT (parents->data)) {
985 typename = G_OBJECT_TYPE_NAME (parents->data);
989 if (GST_IS_OBJECT (parents->data)) {
990 GstObject *item = GST_OBJECT_CAST (parents->data);
991 GstObjectClass *oclass = GST_OBJECT_GET_CLASS (item);
992 gchar *objname = gst_object_get_name (item);
994 component = g_strdup_printf ("%s:%s", typename, objname);
995 separator = oclass->path_string_separator;
997 gst_object_unref (item);
1001 component = g_strdup_printf ("%s:%p", typename, parents->data);
1003 component = g_strdup_printf ("%p", parents->data);
1009 path = g_strjoin (separator, prevpath, component, NULL);
1014 g_slist_free (parentage);
1019 /* controller helper functions */
1022 * gst_object_find_control_binding:
1023 * @self: the gobject to search for a property in
1024 * @name: the gobject property name to look for
1026 * Searches the list of properties under control.
1028 * Returns: (nullable): a #GstControlBinding or %NULL if the property
1029 * is not being controlled.
1031 static GstControlBinding *
1032 gst_object_find_control_binding (GstObject * self, const gchar * name)
1034 GstControlBinding *binding;
1037 for (node = self->control_bindings; node; node = g_list_next (node)) {
1038 binding = node->data;
1039 /* FIXME: eventually use GQuark to speed it up */
1040 if (!strcmp (binding->name, name)) {
1041 GST_DEBUG_OBJECT (self, "found control binding for property '%s'", name);
1045 GST_DEBUG_OBJECT (self, "controller does not manage property '%s'", name);
1050 /* controller functions */
1053 * gst_object_suggest_next_sync:
1054 * @object: the object that has controlled properties
1056 * Returns a suggestion for timestamps where buffers should be split
1057 * to get best controller results.
1059 * Returns: Returns the suggested timestamp or %GST_CLOCK_TIME_NONE
1060 * if no control-rate was set.
1063 gst_object_suggest_next_sync (GstObject * object)
1067 g_return_val_if_fail (GST_IS_OBJECT (object), GST_CLOCK_TIME_NONE);
1068 g_return_val_if_fail (object->control_rate != GST_CLOCK_TIME_NONE,
1069 GST_CLOCK_TIME_NONE);
1071 GST_OBJECT_LOCK (object);
1073 /* TODO: Implement more logic, depending on interpolation mode and control
1075 * FIXME: we need playback direction
1077 ret = object->last_sync + object->control_rate;
1079 GST_OBJECT_UNLOCK (object);
1085 * gst_object_sync_values:
1086 * @object: the object that has controlled properties
1087 * @timestamp: the time that should be processed
1089 * Sets the properties of the object, according to the #GstControlSources that
1090 * (maybe) handle them and for the given timestamp.
1092 * If this function fails, it is most likely the application developers fault.
1093 * Most probably the control sources are not setup correctly.
1095 * Returns: %TRUE if the controller values could be applied to the object
1096 * properties, %FALSE otherwise
1099 gst_object_sync_values (GstObject * object, GstClockTime timestamp)
1102 gboolean ret = TRUE;
1104 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
1105 g_return_val_if_fail (GST_CLOCK_TIME_IS_VALID (timestamp), FALSE);
1107 GST_LOG_OBJECT (object, "sync_values");
1108 if (!object->control_bindings)
1111 /* FIXME: this deadlocks */
1112 /* GST_OBJECT_LOCK (object); */
1113 g_object_freeze_notify ((GObject *) object);
1114 for (node = object->control_bindings; node; node = g_list_next (node)) {
1115 ret &= gst_control_binding_sync_values ((GstControlBinding *) node->data,
1116 object, timestamp, object->last_sync);
1118 object->last_sync = timestamp;
1119 g_object_thaw_notify ((GObject *) object);
1120 /* GST_OBJECT_UNLOCK (object); */
1127 * gst_object_has_active_control_bindings:
1128 * @object: the object that has controlled properties
1130 * Check if the @object has active controlled properties.
1132 * Returns: %TRUE if the object has active controlled properties
1135 gst_object_has_active_control_bindings (GstObject * object)
1137 gboolean res = FALSE;
1140 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
1142 GST_OBJECT_LOCK (object);
1143 for (node = object->control_bindings; node; node = g_list_next (node)) {
1144 res |= !gst_control_binding_is_disabled ((GstControlBinding *) node->data);
1146 GST_OBJECT_UNLOCK (object);
1151 * gst_object_set_control_bindings_disabled:
1152 * @object: the object that has controlled properties
1153 * @disabled: boolean that specifies whether to disable the controller
1156 * This function is used to disable all controlled properties of the @object for
1157 * some time, i.e. gst_object_sync_values() will do nothing.
1160 gst_object_set_control_bindings_disabled (GstObject * object, gboolean disabled)
1164 g_return_if_fail (GST_IS_OBJECT (object));
1166 GST_OBJECT_LOCK (object);
1167 for (node = object->control_bindings; node; node = g_list_next (node)) {
1168 gst_control_binding_set_disabled ((GstControlBinding *) node->data,
1171 GST_OBJECT_UNLOCK (object);
1175 * gst_object_set_control_binding_disabled:
1176 * @object: the object that has controlled properties
1177 * @property_name: property to disable
1178 * @disabled: boolean that specifies whether to disable the controller
1181 * This function is used to disable the control bindings on a property for
1182 * some time, i.e. gst_object_sync_values() will do nothing for the
1186 gst_object_set_control_binding_disabled (GstObject * object,
1187 const gchar * property_name, gboolean disabled)
1189 GstControlBinding *binding;
1191 g_return_if_fail (GST_IS_OBJECT (object));
1192 g_return_if_fail (property_name);
1194 GST_OBJECT_LOCK (object);
1195 if ((binding = gst_object_find_control_binding (object, property_name))) {
1196 gst_control_binding_set_disabled (binding, disabled);
1198 GST_OBJECT_UNLOCK (object);
1203 * gst_object_add_control_binding:
1204 * @object: the controller object
1205 * @binding: (transfer floating): the #GstControlBinding that should be used
1207 * Attach the #GstControlBinding to the object. If there already was a
1208 * #GstControlBinding for this property it will be replaced.
1210 * The object's reference count will be incremented, and any floating
1211 * reference will be removed (see gst_object_ref_sink())
1213 * Returns: %FALSE if the given @binding has not been setup for this object or
1214 * has been setup for a non suitable property, %TRUE otherwise.
1217 gst_object_add_control_binding (GstObject * object, GstControlBinding * binding)
1219 GstControlBinding *old;
1221 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
1222 g_return_val_if_fail (GST_IS_CONTROL_BINDING (binding), FALSE);
1223 g_return_val_if_fail (binding->pspec, FALSE);
1225 GST_OBJECT_LOCK (object);
1226 if ((old = gst_object_find_control_binding (object, binding->name))) {
1227 GST_DEBUG_OBJECT (object, "controlled property %s removed", old->name);
1228 object->control_bindings = g_list_remove (object->control_bindings, old);
1229 gst_object_unparent (GST_OBJECT_CAST (old));
1231 object->control_bindings = g_list_prepend (object->control_bindings, binding);
1232 gst_object_set_parent (GST_OBJECT_CAST (binding), object);
1233 GST_DEBUG_OBJECT (object, "controlled property %s added", binding->name);
1234 GST_OBJECT_UNLOCK (object);
1240 * gst_object_get_control_binding:
1241 * @object: the object
1242 * @property_name: name of the property
1244 * Gets the corresponding #GstControlBinding for the property. This should be
1245 * unreferenced again after use.
1247 * Returns: (transfer full) (nullable): the #GstControlBinding for
1248 * @property_name or %NULL if the property is not controlled.
1251 gst_object_get_control_binding (GstObject * object, const gchar * property_name)
1253 GstControlBinding *binding;
1255 g_return_val_if_fail (GST_IS_OBJECT (object), NULL);
1256 g_return_val_if_fail (property_name, NULL);
1258 GST_OBJECT_LOCK (object);
1259 if ((binding = gst_object_find_control_binding (object, property_name))) {
1260 gst_object_ref (binding);
1262 GST_OBJECT_UNLOCK (object);
1268 * gst_object_remove_control_binding:
1269 * @object: the object
1270 * @binding: the binding
1272 * Removes the corresponding #GstControlBinding. If it was the
1273 * last ref of the binding, it will be disposed.
1275 * Returns: %TRUE if the binding could be removed.
1278 gst_object_remove_control_binding (GstObject * object,
1279 GstControlBinding * binding)
1282 gboolean ret = FALSE;
1284 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
1285 g_return_val_if_fail (GST_IS_CONTROL_BINDING (binding), FALSE);
1287 GST_OBJECT_LOCK (object);
1288 if ((node = g_list_find (object->control_bindings, binding))) {
1289 GST_DEBUG_OBJECT (object, "controlled property %s removed", binding->name);
1290 object->control_bindings =
1291 g_list_delete_link (object->control_bindings, node);
1292 gst_object_unparent (GST_OBJECT_CAST (binding));
1295 GST_OBJECT_UNLOCK (object);
1301 * gst_object_get_value:
1302 * @object: the object that has controlled properties
1303 * @property_name: the name of the property to get
1304 * @timestamp: the time the control-change should be read from
1306 * Gets the value for the given controlled property at the requested time.
1308 * Returns: (nullable): the GValue of the property at the given time,
1309 * or %NULL if the property isn't controlled.
1312 gst_object_get_value (GstObject * object, const gchar * property_name,
1313 GstClockTime timestamp)
1315 GstControlBinding *binding;
1318 g_return_val_if_fail (GST_IS_OBJECT (object), NULL);
1319 g_return_val_if_fail (property_name, NULL);
1320 g_return_val_if_fail (GST_CLOCK_TIME_IS_VALID (timestamp), NULL);
1322 GST_OBJECT_LOCK (object);
1323 if ((binding = gst_object_find_control_binding (object, property_name))) {
1324 val = gst_control_binding_get_value (binding, timestamp);
1326 GST_OBJECT_UNLOCK (object);
1332 * gst_object_get_value_array: (skip)
1333 * @object: the object that has controlled properties
1334 * @property_name: the name of the property to get
1335 * @timestamp: the time that should be processed
1336 * @interval: the time spacing between subsequent values
1337 * @n_values: the number of values
1338 * @values: array to put control-values in
1340 * Gets a number of values for the given controlled property starting at the
1341 * requested time. The array @values need to hold enough space for @n_values of
1342 * the same type as the objects property's type.
1344 * This function is useful if one wants to e.g. draw a graph of the control
1345 * curve or apply a control curve sample by sample.
1347 * The values are unboxed and ready to be used. The similar function
1348 * gst_object_get_g_value_array() returns the array as #GValues and is
1349 * better suites for bindings.
1351 * Returns: %TRUE if the given array could be filled, %FALSE otherwise
1354 gst_object_get_value_array (GstObject * object, const gchar * property_name,
1355 GstClockTime timestamp, GstClockTime interval, guint n_values,
1358 gboolean res = FALSE;
1359 GstControlBinding *binding;
1361 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
1362 g_return_val_if_fail (property_name, FALSE);
1363 g_return_val_if_fail (GST_CLOCK_TIME_IS_VALID (timestamp), FALSE);
1364 g_return_val_if_fail (GST_CLOCK_TIME_IS_VALID (interval), FALSE);
1365 g_return_val_if_fail (values, FALSE);
1367 GST_OBJECT_LOCK (object);
1368 if ((binding = gst_object_find_control_binding (object, property_name))) {
1369 res = gst_control_binding_get_value_array (binding, timestamp, interval,
1372 GST_OBJECT_UNLOCK (object);
1377 * gst_object_get_g_value_array:
1378 * @object: the object that has controlled properties
1379 * @property_name: the name of the property to get
1380 * @timestamp: the time that should be processed
1381 * @interval: the time spacing between subsequent values
1382 * @n_values: the number of values
1383 * @values: (array length=n_values): array to put control-values in
1385 * Gets a number of #GValues for the given controlled property starting at the
1386 * requested time. The array @values need to hold enough space for @n_values of
1389 * This function is useful if one wants to e.g. draw a graph of the control
1390 * curve or apply a control curve sample by sample.
1392 * Returns: %TRUE if the given array could be filled, %FALSE otherwise
1395 gst_object_get_g_value_array (GstObject * object, const gchar * property_name,
1396 GstClockTime timestamp, GstClockTime interval, guint n_values,
1399 gboolean res = FALSE;
1400 GstControlBinding *binding;
1402 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
1403 g_return_val_if_fail (property_name, FALSE);
1404 g_return_val_if_fail (GST_CLOCK_TIME_IS_VALID (timestamp), FALSE);
1405 g_return_val_if_fail (GST_CLOCK_TIME_IS_VALID (interval), FALSE);
1406 g_return_val_if_fail (values, FALSE);
1408 GST_OBJECT_LOCK (object);
1409 if ((binding = gst_object_find_control_binding (object, property_name))) {
1410 res = gst_control_binding_get_g_value_array (binding, timestamp, interval,
1413 GST_OBJECT_UNLOCK (object);
1419 * gst_object_get_control_rate:
1420 * @object: the object that has controlled properties
1422 * Obtain the control-rate for this @object. Audio processing #GstElement
1423 * objects will use this rate to sub-divide their processing loop and call
1424 * gst_object_sync_values() inbetween. The length of the processing segment
1425 * should be up to @control-rate nanoseconds.
1427 * If the @object is not under property control, this will return
1428 * %GST_CLOCK_TIME_NONE. This allows the element to avoid the sub-dividing.
1430 * The control-rate is not expected to change if the element is in
1431 * %GST_STATE_PAUSED or %GST_STATE_PLAYING.
1433 * Returns: the control rate in nanoseconds
1436 gst_object_get_control_rate (GstObject * object)
1438 g_return_val_if_fail (GST_IS_OBJECT (object), FALSE);
1440 return object->control_rate;
1444 * gst_object_set_control_rate:
1445 * @object: the object that has controlled properties
1446 * @control_rate: the new control-rate in nanoseconds.
1448 * Change the control-rate for this @object. Audio processing #GstElement
1449 * objects will use this rate to sub-divide their processing loop and call
1450 * gst_object_sync_values() inbetween. The length of the processing segment
1451 * should be up to @control-rate nanoseconds.
1453 * The control-rate should not change if the element is in %GST_STATE_PAUSED or
1454 * %GST_STATE_PLAYING.
1457 gst_object_set_control_rate (GstObject * object, GstClockTime control_rate)
1459 g_return_if_fail (GST_IS_OBJECT (object));
1461 object->control_rate = control_rate;