gstreamer/gst/gstbin.c
Wim Taymans d7a5d173c8 Documentation updates
Original commit message from CVS:
Documentation updates
Added dump to identity
Fix some warnings in gstelement
2002-03-31 14:04:50 +00:00

855 lines
23 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstbin.c: GstBin container object and support code
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/* #define GST_DEBUG_ENABLED */
#include "gst_private.h"
#include "gstevent.h"
#include "gstbin.h"
#include "gstxml.h"
#include "gstscheduler.h"
GstElementDetails gst_bin_details = {
"Generic bin",
"Bin",
"Simple container object",
VERSION,
"Erik Walthinsen <omega@cse.ogi.edu>",
"(C) 1999",
};
GType _gst_bin_type = 0;
static void gst_bin_dispose (GObject * object);
static GstElementStateReturn gst_bin_change_state (GstElement *element);
static GstElementStateReturn gst_bin_change_state_norecurse (GstBin *bin);
static gboolean gst_bin_change_state_type (GstBin *bin,
GstElementState state,
GType type);
static gboolean gst_bin_iterate_func (GstBin * bin);
#ifndef GST_DISABLE_LOADSAVE
static xmlNodePtr gst_bin_save_thyself (GstObject * object, xmlNodePtr parent);
static void gst_bin_restore_thyself (GstObject * object, xmlNodePtr self);
#endif
/* Bin signals and args */
enum
{
OBJECT_ADDED,
LAST_SIGNAL
};
enum
{
ARG_0,
/* FILL ME */
};
static void gst_bin_class_init (GstBinClass * klass);
static void gst_bin_init (GstBin * bin);
static GstElementClass *parent_class = NULL;
static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
GType
gst_bin_get_type (void)
{
if (!_gst_bin_type) {
static const GTypeInfo bin_info = {
sizeof (GstBinClass),
NULL,
NULL,
(GClassInitFunc) gst_bin_class_init,
NULL,
NULL,
sizeof (GstBin),
8,
(GInstanceInitFunc) gst_bin_init,
NULL
};
_gst_bin_type = g_type_register_static (GST_TYPE_ELEMENT, "GstBin", &bin_info, 0);
}
return _gst_bin_type;
}
static void
gst_bin_class_init (GstBinClass * klass)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass *) klass;
gstobject_class = (GstObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
gst_bin_signals[OBJECT_ADDED] =
g_signal_new ("object_added", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_FIRST,
G_STRUCT_OFFSET (GstBinClass, object_added), NULL, NULL,
gst_marshal_VOID__POINTER, G_TYPE_NONE, 1, G_TYPE_POINTER);
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_bin_dispose);
#ifndef GST_DISABLE_LOADSAVE
gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_bin_save_thyself);
gstobject_class->restore_thyself = GST_DEBUG_FUNCPTR (gst_bin_restore_thyself);
#endif
gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_bin_change_state);
klass->change_state_type = GST_DEBUG_FUNCPTR (gst_bin_change_state_type);
klass->iterate = GST_DEBUG_FUNCPTR (gst_bin_iterate_func);
}
static void
gst_bin_init (GstBin * bin)
{
/* in general, we prefer to use cothreads for most things */
GST_FLAG_SET (bin, GST_BIN_FLAG_PREFER_COTHREADS);
bin->numchildren = 0;
bin->children = NULL;
}
/**
* gst_bin_new:
* @name: name of new bin
*
* Create a new bin with given name.
*
* Returns: new bin
*/
GstElement *
gst_bin_new (const gchar * name)
{
return gst_elementfactory_make ("bin", name);
}
/**
* gst_bin_get_clock:
* @bin: the bin to get the clock of
*
* Get the current clock of the bin
*
* Returns: the clock of the bin
*/
GstClock*
gst_bin_get_clock (GstBin *bin)
{
g_return_val_if_fail (bin != NULL, NULL);
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
if (GST_ELEMENT_SCHED (bin))
return gst_scheduler_get_clock (GST_ELEMENT_SCHED (bin));
return NULL;
}
/**
* gst_bin_use_clock:
* @bin: the bin to set the clock for
* @clock: the clock to use.
*
* Force the bin to use the given clock. Use NULL to
* force it to use no clock at all.
*/
void
gst_bin_use_clock (GstBin *bin, GstClock *clock)
{
g_return_if_fail (bin != NULL);
g_return_if_fail (GST_IS_BIN (bin));
if (GST_ELEMENT_SCHED (bin))
gst_scheduler_use_clock (GST_ELEMENT_SCHED (bin), clock);
}
/**
* gst_bin_auto_clock:
* @bin: the bin to autoclock
*
* Let the bin select a clock automatically.
*/
void
gst_bin_auto_clock (GstBin *bin)
{
g_return_if_fail (bin != NULL);
g_return_if_fail (GST_IS_BIN (bin));
if (GST_ELEMENT_SCHED (bin))
gst_scheduler_auto_clock (GST_ELEMENT_SCHED (bin));
}
static void
gst_bin_set_element_sched (GstElement *element, GstScheduler *sched)
{
GList *children;
GstElement *child;
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (sched != NULL);
g_return_if_fail (GST_IS_SCHEDULER (sched));
GST_INFO (GST_CAT_SCHEDULING, "setting element \"%s\" sched to %p", GST_ELEMENT_NAME (element),
sched);
/* if it's actually a Bin */
if (GST_IS_BIN (element)) {
if (GST_FLAG_IS_SET (element, GST_BIN_FLAG_MANAGER)) {
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, element, "child is already a manager, not resetting");
gst_scheduler_add_scheduler (sched, GST_ELEMENT_SCHED (element));
return;
}
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, element, "setting children's schedule to parent's");
gst_scheduler_add_element (sched, element);
/* set the children's schedule */
children = GST_BIN (element)->children;
while (children) {
child = GST_ELEMENT (children->data);
children = g_list_next (children);
gst_bin_set_element_sched (child, sched);
}
}
/* otherwise, if it's just a regular old element */
else {
gst_scheduler_add_element (sched, element);
}
}
static void
gst_bin_unset_element_sched (GstElement *element, GstScheduler *sched)
{
GList *children;
GstElement *child;
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
if (GST_ELEMENT_SCHED (element) == NULL) {
GST_INFO (GST_CAT_SCHEDULING, "element \"%s\" has no scheduler",
GST_ELEMENT_NAME (element));
return;
}
GST_INFO (GST_CAT_SCHEDULING, "removing element \"%s\" from its sched %p",
GST_ELEMENT_NAME (element), GST_ELEMENT_SCHED (element));
/* if it's actually a Bin */
if (GST_IS_BIN (element)) {
if (GST_FLAG_IS_SET (element, GST_BIN_FLAG_MANAGER)) {
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, element,
"child is already a manager, not unsetting sched");
if (sched) {
gst_scheduler_remove_scheduler (sched, GST_ELEMENT_SCHED (element));
}
return;
}
/* for each child, remove them from their schedule */
children = GST_BIN (element)->children;
while (children) {
child = GST_ELEMENT (children->data);
children = g_list_next (children);
gst_bin_unset_element_sched (child, sched);
}
gst_scheduler_remove_element (GST_ELEMENT_SCHED (element), element);
}
/* otherwise, if it's just a regular old element */
else {
gst_scheduler_remove_element (GST_ELEMENT_SCHED (element), element);
}
}
/**
* gst_bin_add_many:
* @bin: the bin to add the elements to
* @element_1: the first element to add to the bin
* @...: NULL-terminated list of elements to add to the bin
*
* Add a list of elements to a bin. Uses #gst_bin_add.
*/
void
gst_bin_add_many (GstBin *bin, GstElement *element_1, ...)
{
va_list args;
g_return_if_fail (bin != NULL);
g_return_if_fail (element_1 != NULL);
g_return_if_fail (GST_IS_BIN (bin));
g_return_if_fail (GST_IS_ELEMENT (element_1));
va_start (args, element_1);
while (element_1) {
gst_bin_add (bin, element_1);
element_1 = va_arg (args, GstElement*);
}
va_end (args);
}
/**
* gst_bin_add:
* @bin: #GstBin to add element to
* @element: #GstElement to add to bin
*
* Add the given element to the bin. Set the elements parent, and thus
* add a reference.
*/
void
gst_bin_add (GstBin *bin, GstElement *element)
{
gint state_idx = 0;
GstElementState state;
GstScheduler *sched;
g_return_if_fail (bin != NULL);
g_return_if_fail (GST_IS_BIN (bin));
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
GST_DEBUG (GST_CAT_PARENTAGE, "adding element \"%s\" to bin \"%s\"",
GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
/* must be not be in PLAYING state in order to modify bin */
g_return_if_fail (GST_STATE (bin) != GST_STATE_PLAYING);
/* the element must not already have a parent */
g_return_if_fail (GST_ELEMENT_PARENT (element) == NULL);
/* then check to see if the element's name is already taken in the bin */
g_return_if_fail (gst_object_check_uniqueness (bin->children, GST_ELEMENT_NAME (element)) ==
TRUE);
/* set the element's parent and add the element to the bin's list of children */
gst_object_set_parent (GST_OBJECT (element), GST_OBJECT (bin));
bin->children = g_list_append (bin->children, element);
bin->numchildren++;
/* bump our internal state counter */
state = GST_STATE (element);
while (state >>= 1) state_idx++;
bin->child_states[state_idx]++;
/* now we have to deal with manager stuff
* we can only do this if there's a scheduler:
* if we're not a manager, and aren't attached to anything, we have no sched (yet) */
sched = GST_ELEMENT_SCHED (bin);
if (sched) {
gst_bin_set_element_sched (element, sched);
}
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, bin, "added child \"%s\"", GST_ELEMENT_NAME (element));
g_signal_emit (G_OBJECT (bin), gst_bin_signals[OBJECT_ADDED], 0, element);
}
/**
* gst_bin_remove:
* @bin: #GstBin to remove element from
* @element: #GstElement to remove
*
* Remove the element from its associated bin, unparenting as well.
*/
void
gst_bin_remove (GstBin *bin, GstElement *element)
{
gint state_idx = 0;
GstElementState state;
GST_DEBUG_ELEMENT (GST_CAT_PARENTAGE, bin, "trying to remove child %s\n", GST_ELEMENT_NAME (element));
g_return_if_fail (bin != NULL);
g_return_if_fail (GST_IS_BIN (bin));
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (bin->children != NULL);
/* must not be in PLAYING state in order to modify bin */
g_return_if_fail (GST_STATE (bin) != GST_STATE_PLAYING);
/* the element must have its parent set to the current bin */
g_return_if_fail (GST_ELEMENT_PARENT (element) == (GstObject *) bin);
/* the element must be in the bin's list of children */
if (g_list_find (bin->children, element) == NULL) {
g_warning ("no element \"%s\" in bin \"%s\"\n", GST_ELEMENT_NAME (element),
GST_ELEMENT_NAME (bin));
return;
}
/* remove this element from the list of managed elements */
gst_bin_unset_element_sched (element, GST_ELEMENT_SCHED (bin));
/* now remove the element from the list of elements */
bin->children = g_list_remove (bin->children, element);
bin->numchildren--;
/* bump our internal state counter */
state = GST_STATE (element);
while (state >>= 1) state_idx++;
bin->child_states[state_idx]--;
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, bin, "removed child %s", GST_ELEMENT_NAME (element));
gst_object_unparent (GST_OBJECT (element));
/* if we're down to zero children, force state to NULL */
if (bin->numchildren == 0 && GST_ELEMENT_SCHED (bin) != NULL) {
GST_STATE_PENDING (bin) = GST_STATE_NULL;
gst_bin_change_state_norecurse (bin);
}
}
/**
* gst_bin_child_state_change:
* @bin: #GstBin with the child
* @oldstate: The old child state
* @newstate: The new child state
* @child: #GstElement that signaled an changed state
*
* An internal function to inform the parent bin about a state change
* of a child.
*/
void
gst_bin_child_state_change (GstBin *bin, GstElementState oldstate, GstElementState newstate,
GstElement *child)
{
gint old_idx = 0, new_idx = 0, i;
GST_INFO (GST_CAT_STATES, "child %s changed state in bin %s from %s to %s",
GST_ELEMENT_NAME (child), GST_ELEMENT_NAME (bin),
gst_element_statename (oldstate), gst_element_statename (newstate));
while (oldstate >>= 1) old_idx++;
while (newstate >>= 1) new_idx++;
GST_LOCK (bin);
bin->child_states[old_idx]--;
bin->child_states[new_idx]++;
for (i = GST_NUM_STATES - 1; i >= 0; i--) {
if (bin->child_states[i] != 0) {
gint state = (1 << i);
if (GST_STATE (bin) != state) {
GST_INFO (GST_CAT_STATES, "bin %s need state change to %s",
GST_ELEMENT_NAME (bin), gst_element_statename (state));
GST_STATE_PENDING (bin) = state;
GST_UNLOCK (bin);
gst_bin_change_state_norecurse (bin);
return;
}
break;
}
}
GST_UNLOCK (bin);
}
static GstElementStateReturn
gst_bin_change_state (GstElement * element)
{
GstBin *bin;
GList *children;
GstElement *child;
GstElementStateReturn ret;
GstElementState old_state, pending;
gint transition;
gboolean have_async = FALSE;
g_return_val_if_fail (GST_IS_BIN (element), GST_STATE_FAILURE);
bin = GST_BIN (element);
old_state = GST_STATE (element);
pending = GST_STATE_PENDING (element);
transition = GST_STATE_TRANSITION (element);
GST_INFO_ELEMENT (GST_CAT_STATES, element, "changing childrens' state from %s to %s",
gst_element_statename (old_state), gst_element_statename (pending));
if (pending == GST_STATE_VOID_PENDING)
return GST_STATE_SUCCESS;
children = bin->children;
while (children) {
child = GST_ELEMENT (children->data);
children = g_list_next (children);
switch (gst_element_set_state (child, pending)) {
case GST_STATE_FAILURE:
GST_STATE_PENDING (element) = GST_STATE_VOID_PENDING;
GST_DEBUG (GST_CAT_STATES, "child '%s' failed to go to state %d(%s)",
GST_ELEMENT_NAME (child), pending, gst_element_statename (pending));
gst_element_set_state (child, old_state);
if (GST_ELEMENT_SCHED (child) == GST_ELEMENT_SCHED (element)) {
/* reset to what is was */
GST_STATE_PENDING (element) = old_state;
gst_bin_change_state (element);
return GST_STATE_FAILURE;
}
break;
case GST_STATE_ASYNC:
GST_DEBUG (GST_CAT_STATES, "child '%s' is changing state asynchronously",
GST_ELEMENT_NAME (child));
have_async = TRUE;
break;
}
}
GST_INFO_ELEMENT (GST_CAT_STATES, element, "done changing bin's state from %s to %s, now in %s",
gst_element_statename (old_state),
gst_element_statename (pending),
gst_element_statename (GST_STATE (element)));
if (have_async)
ret = GST_STATE_ASYNC;
else
ret = GST_STATE_SUCCESS;
return ret;
}
static GstElementStateReturn
gst_bin_change_state_norecurse (GstBin * bin)
{
GstElementStateReturn ret;
if (GST_ELEMENT_CLASS (parent_class)->change_state) {
GST_DEBUG_ELEMENT (GST_CAT_STATES, bin, "setting bin's own state\n");
ret = GST_ELEMENT_CLASS (parent_class)->change_state (GST_ELEMENT (bin));
return ret;
}
else
return GST_STATE_FAILURE;
}
static gboolean
gst_bin_change_state_type (GstBin * bin, GstElementState state, GType type)
{
GList *children;
GstElement *child;
g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
g_return_val_if_fail (bin->numchildren != 0, FALSE);
children = bin->children;
while (children) {
child = GST_ELEMENT (children->data);
if (GST_IS_BIN (child)) {
if (!gst_bin_set_state_type (GST_BIN (child), state, type))
return FALSE;
}
else if (G_TYPE_CHECK_INSTANCE_TYPE (child, type)) {
if (!gst_element_set_state (child, state))
return FALSE;
}
children = g_list_next (children);
}
if (type == GST_TYPE_BIN)
gst_element_set_state (GST_ELEMENT (bin), state);
return TRUE;
}
/**
* gst_bin_set_state_type:
* @bin: #GstBin to set the state
* @state: the new state to set the elements to
* @type: the type of elements to change
*
* Sets the state of only those objects of the given type.
*
* Returns: indication if the state change was successfull
*/
gboolean
gst_bin_set_state_type (GstBin * bin, GstElementState state, GType type)
{
GstBinClass *oclass;
GST_DEBUG (GST_CAT_STATES, "gst_bin_set_state_type(\"%s\",%d,%s)",
GST_ELEMENT_NAME (bin), state, G_OBJECT_TYPE_NAME (type));
g_return_val_if_fail (bin != NULL, FALSE);
g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
oclass = GST_BIN_CLASS (G_OBJECT_GET_CLASS (bin));
if (oclass->change_state_type)
(oclass->change_state_type) (bin, state, type);
return TRUE;
}
static void
gst_bin_dispose (GObject * object)
{
GstBin *bin = GST_BIN (object);
GList *children, *orig;
GstElement *child;
GST_DEBUG (GST_CAT_REFCOUNTING, "dispose");
if (gst_element_get_state (GST_ELEMENT (object)) == GST_STATE_PLAYING)
gst_element_set_state (GST_ELEMENT (object), GST_STATE_PAUSED);
if (bin->children) {
orig = children = g_list_copy (bin->children);
while (children) {
child = GST_ELEMENT (children->data);
gst_bin_remove (bin, child);
children = g_list_next (children);
}
g_list_free (bin->children);
g_list_free (orig);
}
bin->children = NULL;
bin->numchildren = 0;
G_OBJECT_CLASS (parent_class)->dispose (object);
}
/**
* gst_bin_get_by_name:
* @bin: #Gstbin to search
* @name: the element name to search for
*
* Get the element with the given name from this bin.
*
* Returns: the element with the given name
*/
GstElement *
gst_bin_get_by_name (GstBin * bin, const gchar * name)
{
GList *children;
GstElement *child;
g_return_val_if_fail (bin != NULL, NULL);
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
g_return_val_if_fail (name != NULL, NULL);
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, bin, "looking up child element %s", name);
children = bin->children;
while (children) {
child = GST_ELEMENT (children->data);
if (!strcmp (GST_OBJECT_NAME (child), name))
return child;
if (GST_IS_BIN (child)) {
GstElement *res = gst_bin_get_by_name (GST_BIN (child), name);
if (res)
return res;
}
children = g_list_next (children);
}
return NULL;
}
/**
* gst_bin_get_by_name_recurse_up:
* @bin: #Gstbin to search
* @name: the element name to search for
*
* Get the element with the given name from this bin. If the
* element is not found, a recursion is performed on the parent bin.
*
* Returns: the element with the given name
*/
GstElement *
gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
{
GstElement *result = NULL;
GstObject *parent;
g_return_val_if_fail (bin != NULL, NULL);
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
g_return_val_if_fail (name != NULL, NULL);
result = gst_bin_get_by_name (bin, name);
if (!result) {
parent = gst_object_get_parent (GST_OBJECT (bin));
if (parent && GST_IS_BIN (parent)) {
result = gst_bin_get_by_name_recurse_up (GST_BIN (parent), name);
}
}
return result;
}
/**
* gst_bin_get_list:
* @bin: #Gstbin to get the list from
*
* Get the list of elements in this bin.
*
* Returns: a GList of elements
*/
GList *
gst_bin_get_list (GstBin * bin)
{
g_return_val_if_fail (bin != NULL, NULL);
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
return bin->children;
}
#ifndef GST_DISABLE_LOADSAVE
static xmlNodePtr
gst_bin_save_thyself (GstObject * object, xmlNodePtr parent)
{
GstBin *bin = GST_BIN (object);
xmlNodePtr childlist, elementnode;
GList *children;
GstElement *child;
if (GST_OBJECT_CLASS (parent_class)->save_thyself)
GST_OBJECT_CLASS (parent_class)->save_thyself (GST_OBJECT (bin), parent);
childlist = xmlNewChild (parent, NULL, "children", NULL);
GST_INFO_ELEMENT (GST_CAT_XML, bin, "saving %d children", bin->numchildren);
children = bin->children;
while (children) {
child = GST_ELEMENT (children->data);
elementnode = xmlNewChild (childlist, NULL, "element", NULL);
gst_object_save_thyself (GST_OBJECT (child), elementnode);
children = g_list_next (children);
}
return childlist;
}
static void
gst_bin_restore_thyself (GstObject * object, xmlNodePtr self)
{
GstBin *bin = GST_BIN (object);
xmlNodePtr field = self->xmlChildrenNode;
xmlNodePtr childlist;
while (field) {
if (!strcmp (field->name, "children")) {
GST_INFO_ELEMENT (GST_CAT_XML, GST_ELEMENT (object), "loading children");
childlist = field->xmlChildrenNode;
while (childlist) {
if (!strcmp (childlist->name, "element")) {
GstElement *element = gst_xml_make_element (childlist, GST_OBJECT (bin));
/* it had to be parented to find the pads, now we ref and unparent so
* we can add it to the bin */
gst_object_ref (GST_OBJECT (element));
gst_object_unparent (GST_OBJECT (element));
gst_bin_add (bin, element);
}
childlist = childlist->next;
}
}
field = field->next;
}
}
#endif /* GST_DISABLE_LOADSAVE */
static gboolean
gst_bin_iterate_func (GstBin * bin)
{
/* only iterate if this is the manager bin */
if (GST_ELEMENT_SCHED (bin) &&
GST_ELEMENT_SCHED (bin)->parent == GST_ELEMENT (bin)) {
GstSchedulerState state;
state = gst_scheduler_iterate (GST_ELEMENT_SCHED (bin));
if (state == GST_SCHEDULER_STATE_RUNNING) {
return TRUE;
}
else if (state == GST_SCHEDULER_STATE_ERROR) {
gst_element_set_state (GST_ELEMENT (bin), GST_STATE_PAUSED);
}
}
else {
g_warning ("bin \"%s\" can't be iterated on!\n", GST_ELEMENT_NAME (bin));
}
return FALSE;
}
/**
* gst_bin_iterate:
* @bin: #Gstbin to iterate
*
* Iterates over the elements in this bin.
*
* Returns: TRUE if the bin did something usefull. This value
* can be used to determine it the bin is in EOS.
*/
gboolean
gst_bin_iterate (GstBin * bin)
{
GstBinClass *oclass;
gboolean running = TRUE;
GST_DEBUG_ENTER ("(\"%s\")", GST_ELEMENT_NAME (bin));
g_return_val_if_fail (bin != NULL, FALSE);
g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
oclass = GST_BIN_CLASS (G_OBJECT_GET_CLASS (bin));
if (oclass->iterate)
running = (oclass->iterate) (bin);
GST_DEBUG_LEAVE ("(\"%s\") %d", GST_ELEMENT_NAME (bin), running);
if (!running) {
if (GST_STATE (bin) == GST_STATE_PLAYING && GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
GST_DEBUG_ELEMENT (GST_CAT_DATAFLOW, bin,
"waiting for child shutdown after useless iteration\n");
gst_element_wait_state_change (GST_ELEMENT (bin));
GST_DEBUG_ELEMENT (GST_CAT_DATAFLOW, bin, "child shutdown\n");
}
}
return running;
}