mirrors/gstreamer
mirrors/gstreamer
1
1
Fork 0
mirror of https://gitlab.freedesktop.org/gstreamer/gstreamer.git synced 2024-11-06 01:19:38 +00:00
Code Issues 1 Projects Releases Wiki Activity
gstreamer/gst/gstelement.c
Benjamin Otte 05adc8c15c implement proper refcounting of pad's templates and references from real pads to their ghost pads and the other way a... 
Original commit message from CVS:
implement proper refcounting of pad's templates and references from real pads to their ghost pads and the other way around - this fixes the segfaults in the player
2003-05-06 21:58:49 +00:00

3020 lines
87 KiB
C
Raw Blame History

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstelement.c: The base element, all elements derive from this
*
* 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 <glib.h>
#include <stdarg.h>
#include <gobject/gvaluecollector.h>
#include "gst_private.h"
#include "gstelement.h"
#include "gstbin.h"
#include "gstscheduler.h"
#include "gstevent.h"
#include "gstutils.h"
#include "gstlog.h"
/* Element signals and args */
enum {
STATE_CHANGE,
NEW_PAD,
PAD_REMOVED,
ERROR,
EOS,
LAST_SIGNAL
};
enum {
ARG_0,
/* FILL ME */
};
static void gst_element_class_init (GstElementClass *klass);
static void gst_element_init (GstElement *element);
static void gst_element_base_class_init (GstElementClass *klass);
static void gst_element_real_set_property (GObject *object, guint prop_id,
const GValue *value, GParamSpec *pspec);
static void gst_element_real_get_property (GObject *object, guint prop_id, GValue *value,
GParamSpec *pspec);
static void gst_element_dispose (GObject *object);
static GstElementStateReturn gst_element_change_state (GstElement *element);
static void gst_element_error_func (GstElement* element, GstElement *source, gchar *errormsg);
#ifndef GST_DISABLE_LOADSAVE
static xmlNodePtr gst_element_save_thyself (GstObject *object, xmlNodePtr parent);
static void gst_element_restore_thyself (GstObject *parent, xmlNodePtr self);
#endif
GType _gst_element_type = 0;
static GstObjectClass *parent_class = NULL;
static guint gst_element_signals[LAST_SIGNAL] = { 0 };
GType gst_element_get_type (void)
{
if (!_gst_element_type) {
static const GTypeInfo element_info = {
sizeof(GstElementClass),
(GBaseInitFunc)gst_element_base_class_init,
NULL,
(GClassInitFunc)gst_element_class_init,
NULL,
NULL,
sizeof(GstElement),
0,
(GInstanceInitFunc)gst_element_init,
NULL
};
_gst_element_type = g_type_register_static(GST_TYPE_OBJECT, "GstElement",
&element_info, G_TYPE_FLAG_ABSTRACT);
}
return _gst_element_type;
}
static void
gst_element_class_init (GstElementClass *klass)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
gobject_class = (GObjectClass*) klass;
gstobject_class = (GstObjectClass*) klass;
parent_class = g_type_class_ref(GST_TYPE_OBJECT);
gst_element_signals[STATE_CHANGE] =
g_signal_new ("state_change", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstElementClass, state_change), NULL, NULL,
gst_marshal_VOID__INT_INT, G_TYPE_NONE, 2,
G_TYPE_INT, G_TYPE_INT);
gst_element_signals[NEW_PAD] =
g_signal_new ("new_pad", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstElementClass, new_pad), NULL, NULL,
gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1,
G_TYPE_OBJECT);
gst_element_signals[PAD_REMOVED] =
g_signal_new ("pad_removed", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstElementClass, pad_removed), NULL, NULL,
gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1,
G_TYPE_OBJECT);
gst_element_signals[ERROR] =
g_signal_new ("error", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstElementClass, error), NULL, NULL,
gst_marshal_VOID__OBJECT_STRING, G_TYPE_NONE, 2,
G_TYPE_OBJECT, G_TYPE_STRING);
gst_element_signals[EOS] =
g_signal_new ("eos", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstElementClass,eos), NULL, NULL,
gst_marshal_VOID__VOID, G_TYPE_NONE, 0);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_element_real_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_element_real_get_property);
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_element_dispose);
#ifndef GST_DISABLE_LOADSAVE
gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_element_save_thyself);
gstobject_class->restore_thyself = GST_DEBUG_FUNCPTR (gst_element_restore_thyself);
#endif
klass->change_state = GST_DEBUG_FUNCPTR (gst_element_change_state);
klass->error = GST_DEBUG_FUNCPTR (gst_element_error_func);
klass->elementfactory = NULL;
klass->padtemplates = NULL;
klass->numpadtemplates = 0;
}
static void
gst_element_base_class_init (GstElementClass *klass)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass*) klass;
gobject_class->set_property = GST_DEBUG_FUNCPTR(gst_element_real_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR(gst_element_real_get_property);
}
static void
gst_element_init (GstElement *element)
{
element->current_state = GST_STATE_NULL;
element->pending_state = GST_STATE_VOID_PENDING;
element->numpads = 0;
element->numsrcpads = 0;
element->numsinkpads = 0;
element->pads = NULL;
element->loopfunc = NULL;
element->sched = NULL;
element->clock = NULL;
element->sched_private = NULL;
element->state_mutex = g_mutex_new ();
element->state_cond = g_cond_new ();
}
static void
gst_element_real_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
{
GstElementClass *oclass = GST_ELEMENT_GET_CLASS (object);
if (oclass->set_property)
(oclass->set_property) (object, prop_id, value, pspec);
}
static void
gst_element_real_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
{
GstElementClass *oclass = GST_ELEMENT_GET_CLASS (object);
if (oclass->get_property)
(oclass->get_property) (object, prop_id, value, pspec);
}
/**
* gst_element_default_error:
* @object: a #GObject that signalled the error.
* @orig: the #GstObject that initiated the error.
* @error: the error message.
*
* Adds a default error signal callback to an
* element. The user data passed to the g_signal_connect is
* ignored.
* The default handler will simply print the error string
* using g_print.
*/
void
gst_element_default_error (GObject *object, GstObject *orig, gchar *error)
{
gchar *name = gst_object_get_path_string (orig);
g_print ("ERROR: %s: %s\n", name, error);
g_free (name);
}
typedef struct {
const GParamSpec *pspec;
GValue value;
} prop_value_t;
static void
element_set_property (GstElement *element, const GParamSpec *pspec, const GValue *value)
{
prop_value_t *prop_value = g_new0 (prop_value_t, 1);
prop_value->pspec = pspec;
prop_value->value = *value;
g_async_queue_push (element->prop_value_queue, prop_value);
}
static void
element_get_property (GstElement *element, const GParamSpec *pspec, GValue *value)
{
g_mutex_lock (element->property_mutex);
g_object_get_property ((GObject*)element, pspec->name, value);
g_mutex_unlock (element->property_mutex);
}
static void
gst_element_threadsafe_properties_pre_run (GstElement *element)
{
GST_DEBUG (GST_CAT_THREAD, "locking element %s", GST_OBJECT_NAME (element));
g_mutex_lock (element->property_mutex);
gst_element_set_pending_properties (element);
}
static void
gst_element_threadsafe_properties_post_run (GstElement *element)
{
GST_DEBUG (GST_CAT_THREAD, "unlocking element %s", GST_OBJECT_NAME (element));
g_mutex_unlock (element->property_mutex);
}
/**
* gst_element_enable_threadsafe_properties:
* @element: a #GstElement to enable threadsafe properties on.
*
* Installs an asynchronous queue, a mutex and pre- and post-run functions on
* this element so that properties on the element can be set in a
* threadsafe way.
*/
void
gst_element_enable_threadsafe_properties (GstElement *element)
{
g_return_if_fail (GST_IS_ELEMENT (element));
GST_FLAG_SET (element, GST_ELEMENT_USE_THREADSAFE_PROPERTIES);
element->pre_run_func = gst_element_threadsafe_properties_pre_run;
element->post_run_func = gst_element_threadsafe_properties_post_run;
if (!element->prop_value_queue)
element->prop_value_queue = g_async_queue_new ();
if (!element->property_mutex)
element->property_mutex = g_mutex_new ();
}
/**
* gst_element_disable_threadsafe_properties:
* @element: a #GstElement to disable threadsafe properties on.
*
* Removes the threadsafe properties, post- and pre-run locks from
* this element.
*/
void
gst_element_disable_threadsafe_properties (GstElement *element)
{
g_return_if_fail (GST_IS_ELEMENT (element));
GST_FLAG_UNSET (element, GST_ELEMENT_USE_THREADSAFE_PROPERTIES);
element->pre_run_func = NULL;
element->post_run_func = NULL;
/* let's keep around that async queue */
}
/**
* gst_element_set_pending_properties:
* @element: a #GstElement to set the pending properties on.
*
* Sets all pending properties on the threadsafe properties enabled
* element.
*/
void
gst_element_set_pending_properties (GstElement *element)
{
prop_value_t *prop_value;
while ((prop_value = g_async_queue_try_pop (element->prop_value_queue))) {
g_object_set_property ((GObject*)element, prop_value->pspec->name, &prop_value->value);
g_value_unset (&prop_value->value);
g_free (prop_value);
}
}
/* following 6 functions taken mostly from gobject.c */
/**
* gst_element_set:
* @element: a #GstElement to set properties on.
* @first_property_name: the first property to set.
* @...: value of the first property, and more properties to set, ending
* with NULL.
*
* Sets properties on an element. If the element uses threadsafe properties,
* they will be queued and set on the object when it is scheduled again.
*/
void
gst_element_set (GstElement *element, const gchar *first_property_name, ...)
{
va_list var_args;
g_return_if_fail (GST_IS_ELEMENT (element));
va_start (var_args, first_property_name);
gst_element_set_valist (element, first_property_name, var_args);
va_end (var_args);
}
/**
* gst_element_get:
* @element: a #GstElement to get properties of.
* @first_property_name: the first property to get.
* @...: pointer to a variable to store the first property in, as well as
* more properties to get, ending with NULL.
*
* Gets properties from an element. If the element uses threadsafe properties,
* the element will be locked before getting the given properties.
*/
void
gst_element_get (GstElement *element, const gchar *first_property_name, ...)
{
va_list var_args;
g_return_if_fail (GST_IS_ELEMENT (element));
va_start (var_args, first_property_name);
gst_element_get_valist (element, first_property_name, var_args);
va_end (var_args);
}
/**
* gst_element_set_valist:
* @element: a #GstElement to set properties on.
* @first_property_name: the first property to set.
* @var_args: the var_args list of other properties to get.
*
* Sets properties on an element. If the element uses threadsafe properties,
* the property change will be put on the async queue.
*/
void
gst_element_set_valist (GstElement *element, const gchar *first_property_name, va_list var_args)
{
const gchar *name;
GObject *object;
g_return_if_fail (GST_IS_ELEMENT (element));
object = (GObject *) element;
GST_DEBUG (GST_CAT_PROPERTIES,
"setting valist of properties starting with %s on element %s",
first_property_name, gst_element_get_name (element));
if (!GST_FLAG_IS_SET (element, GST_ELEMENT_USE_THREADSAFE_PROPERTIES)) {
g_object_set_valist (object, first_property_name, var_args);
return;
}
g_object_ref (object);
name = first_property_name;
while (name)
{
GValue value = { 0, };
GParamSpec *pspec;
gchar *error = NULL;
pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (object), name);
if (!pspec)
{
g_warning ("%s: object class `%s' has no property named `%s'",
G_STRLOC,
G_OBJECT_TYPE_NAME (object),
name);
break;
}
if (!(pspec->flags & G_PARAM_WRITABLE))
{
g_warning ("%s: property `%s' of object class `%s' is not writable",
G_STRLOC,
pspec->name,
G_OBJECT_TYPE_NAME (object));
break;
}
g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
G_VALUE_COLLECT (&value, var_args, 0, &error);
if (error)
{
g_warning ("%s: %s", G_STRLOC, error);
g_free (error);
/* we purposely leak the value here, it might not be
* in a sane state if an error condition occoured
*/
break;
}
element_set_property (element, pspec, &value);
g_value_unset (&value);
name = va_arg (var_args, gchar*);
}
g_object_unref (object);
}
/**
* gst_element_get_valist:
* @element: a #GstElement to get properties of.
* @first_property_name: the first property to get.
* @var_args: the var_args list of other properties to get.
*
* Gets properties from an element. If the element uses threadsafe properties,
* the element will be locked before getting the given properties.
*/
void
gst_element_get_valist (GstElement *element, const gchar *first_property_name, va_list var_args)
{
const gchar *name;
GObject *object;
g_return_if_fail (GST_IS_ELEMENT (element));
object = (GObject*)element;
if (!GST_FLAG_IS_SET (element, GST_ELEMENT_USE_THREADSAFE_PROPERTIES)) {
g_object_get_valist (object, first_property_name, var_args);
return;
}
g_object_ref (object);
name = first_property_name;
while (name)
{
GValue value = { 0, };
GParamSpec *pspec;
gchar *error;
pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (object), name);
if (!pspec)
{
g_warning ("%s: object class `%s' has no property named `%s'",
G_STRLOC,
G_OBJECT_TYPE_NAME (object),
name);
break;
}
if (!(pspec->flags & G_PARAM_READABLE))
{
g_warning ("%s: property `%s' of object class `%s' is not readable",
G_STRLOC,
pspec->name,
G_OBJECT_TYPE_NAME (object));
break;
}
g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
element_get_property (element, pspec, &value);
G_VALUE_LCOPY (&value, var_args, 0, &error);
if (error)
{
g_warning ("%s: %s", G_STRLOC, error);
g_free (error);
g_value_unset (&value);
break;
}
g_value_unset (&value);
name = va_arg (var_args, gchar*);
}
g_object_unref (object);
}
/**
* gst_element_set_property:
* @element: a #GstElement to set properties on.
* @property_name: the first property to get.
* @value: the #GValue that holds the value to set.
*
* Sets a property on an element. If the element uses threadsafe properties,
* the property will be put on the async queue.
*/
void
gst_element_set_property (GstElement *element, const gchar *property_name,
const GValue *value)
{
GParamSpec *pspec;
GObject *object;
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (property_name != NULL);
g_return_if_fail (G_IS_VALUE (value));
object = (GObject*) element;
GST_DEBUG (GST_CAT_PROPERTIES, "setting property %s on element %s",
property_name, gst_element_get_name (element));
if (!GST_FLAG_IS_SET (element, GST_ELEMENT_USE_THREADSAFE_PROPERTIES)) {
g_object_set_property (object, property_name, value);
return;
}
g_object_ref (object);
pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (object),
property_name);
if (!pspec)
g_warning ("%s: object class `%s' has no property named `%s'",
G_STRLOC,
G_OBJECT_TYPE_NAME (object),
property_name);
else
element_set_property (element, pspec, value);
g_object_unref (object);
}
/**
* gst_element_get_property:
* @element: a #GstElement to get properties of.
* @property_name: the first property to get.
* @value: the #GValue to store the property value in.
*
* Gets a property from an element. If the element uses threadsafe properties,
* the element will be locked before getting the given property.
*/
void
gst_element_get_property (GstElement *element, const gchar *property_name, GValue *value)
{
GParamSpec *pspec;
GObject *object;
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (property_name != NULL);
g_return_if_fail (G_IS_VALUE (value));
object = (GObject*)element;
if (!GST_FLAG_IS_SET (element, GST_ELEMENT_USE_THREADSAFE_PROPERTIES)) {
g_object_get_property (object, property_name, value);
return;
}
g_object_ref (object);
pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (object), property_name);
if (!pspec)
g_warning ("%s: object class `%s' has no property named `%s'",
G_STRLOC,
G_OBJECT_TYPE_NAME (object),
property_name);
else
{
GValue *prop_value, tmp_value = { 0, };
/* auto-conversion of the callers value type
*/
if (G_VALUE_TYPE (value) == G_PARAM_SPEC_VALUE_TYPE (pspec))
{
g_value_reset (value);
prop_value = value;
}
else if (!g_value_type_transformable (G_PARAM_SPEC_VALUE_TYPE (pspec), G_VALUE_TYPE (value)))
{
g_warning ("can't retrieve property `%s' of type `%s' as value of type `%s'",
pspec->name,
g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspec)),
G_VALUE_TYPE_NAME (value));
g_object_unref (object);
return;
}
else
{
g_value_init (&tmp_value, G_PARAM_SPEC_VALUE_TYPE (pspec));
prop_value = &tmp_value;
}
element_get_property (element, pspec, prop_value);
if (prop_value != value)
{
g_value_transform (prop_value, value);
g_value_unset (&tmp_value);
}
}
g_object_unref (object);
}
static GstPad*
gst_element_request_pad (GstElement *element, GstPadTemplate *templ, const gchar* name)
{
GstPad *newpad = NULL;
GstElementClass *oclass;
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->request_new_pad)
newpad = (oclass->request_new_pad)(element, templ, name);
return newpad;
}
/**
* gst_element_release_request_pad:
* @element: a #GstElement to release the request pad of.
* @pad: the #GstPad to release.
*
* Makes the element free the previously requested pad as obtained
* with gst_element_get_request_pad().
*/
void
gst_element_release_request_pad (GstElement *element, GstPad *pad)
{
GstElementClass *oclass;
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (GST_IS_PAD (pad));
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->release_pad)
(oclass->release_pad) (element, pad);
}
/**
* gst_element_requires_clock:
* @element: a #GstElement to query
*
* Query if the element requiresd a clock
*
* Returns: TRUE if the element requires a clock
*/
gboolean
gst_element_requires_clock (GstElement *element)
{
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
return (GST_ELEMENT_GET_CLASS (element)->set_clock != NULL);
}
/**
* gst_element_provides_clock:
* @element: a #GstElement to query
*
* Query if the element provides a clock
*
* Returns: TRUE if the element provides a clock
*/
gboolean
gst_element_provides_clock (GstElement *element)
{
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
return (GST_ELEMENT_GET_CLASS (element)->get_clock != NULL);
}
/**
* gst_element_set_clock:
* @element: a #GstElement to set the clock for.
* @clock: the #GstClock to set for the element.
*
* Sets the clock for the element.
*/
void
gst_element_set_clock (GstElement *element, GstClock *clock)
{
GstElementClass *oclass;
g_return_if_fail (GST_IS_ELEMENT (element));
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->set_clock)
oclass->set_clock (element, clock);
gst_object_replace ((GstObject **)&element->clock, (GstObject *)clock);
}
/**
* gst_element_get_clock:
* @element: a #GstElement to get the clock of.
*
* Gets the clock of the element.
*
* Returns: the #GstClock of the element.
*/
GstClock*
gst_element_get_clock (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->get_clock)
return oclass->get_clock (element);
return NULL;
}
/**
* gst_element_clock_wait:
* @element: a #GstElement.
* @id: the #GstClock to use.
* @jitter: the difference between requested time and actual time.
*
* Waits for a specific time on the clock.
*
* Returns: the #GstClockReturn result of the wait operation.
*/
GstClockReturn
gst_element_clock_wait (GstElement *element, GstClockID id, GstClockTimeDiff *jitter)
{
GstClockReturn res;
g_return_val_if_fail (GST_IS_ELEMENT (element), GST_CLOCK_ERROR);
if (GST_ELEMENT_SCHED (element)) {
res = gst_scheduler_clock_wait (GST_ELEMENT_SCHED (element), element, id, jitter);
}
else
res = GST_CLOCK_TIMEOUT;
return res;
}
#ifndef GST_DISABLE_INDEX
/**
* gst_element_is_indexable:
* @element: a #GstElement.
*
* Queries if the element can be indexed/
*
* Returns: TRUE if the element can be indexed.
*/
gboolean
gst_element_is_indexable (GstElement *element)
{
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
return (GST_ELEMENT_GET_CLASS (element)->set_index != NULL);
}
/**
* gst_element_set_index:
* @element: a #GstElement.
* @index: a #GstIndex.
*
* Set the specified GstIndex on the element.
*/
void
gst_element_set_index (GstElement *element, GstIndex *index)
{
GstElementClass *oclass;
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (GST_IS_INDEX (index));
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->set_index)
oclass->set_index (element, index);
}
/**
* gst_element_get_index:
* @element: a #GstElement.
*
* Gets the index from the element.
*
* Returns: a #GstIndex or NULL when no index was set on the
* element.
*/
GstIndex*
gst_element_get_index (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->get_index)
return oclass->get_index (element);
return NULL;
}
#endif
/**
* gst_element_release_locks:
* @element: a #GstElement to release all locks on.
*
* Instruct the element to release all the locks it is holding, such as
* blocking reads, waiting for the clock, ...
*
* Returns: TRUE if the locks could be released.
*/
gboolean
gst_element_release_locks (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->release_locks)
return oclass->release_locks (element);
return TRUE;
}
/**
* gst_element_add_pad:
* @element: a #GstElement to add the pad to.
* @pad: the #GstPad to add to the element.
*
* Add a pad (link point) to the element, setting the parent of the
* pad to the element (and thus adding a reference).
* Pads are automatically activated when the element is in state PLAYING.
*/
void
gst_element_add_pad (GstElement *element, GstPad *pad)
{
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (GST_IS_PAD (pad));
/* first check to make sure the pad's parent is already set */
g_return_if_fail (GST_PAD_PARENT (pad) == NULL);
/* then check to see if there's already a pad by that name here */
g_return_if_fail (gst_object_check_uniqueness (element->pads, GST_PAD_NAME(pad)) == TRUE);
/* set the pad's parent */
GST_DEBUG (GST_CAT_ELEMENT_PADS,"setting parent of pad '%s' to '%s'",
GST_PAD_NAME (pad), GST_STR_NULL (GST_ELEMENT_NAME (element)));
gst_object_set_parent (GST_OBJECT (pad), GST_OBJECT (element));
/* add it to the list */
element->pads = g_list_append (element->pads, pad);
element->numpads++;
if (gst_pad_get_direction (pad) == GST_PAD_SRC)
element->numsrcpads++;
else
element->numsinkpads++;
/* activate element when we are playing */
if (GST_STATE (element) == GST_STATE_PLAYING)
gst_pad_set_active (pad, TRUE);
/* emit the NEW_PAD signal */
g_signal_emit (G_OBJECT (element), gst_element_signals[NEW_PAD], 0, pad);
}
/**
* gst_element_remove_pad:
* @element: a #GstElement to remove pad from.
* @pad: the #GstPad to remove from the element.
*
* Remove a pad (link point) from the element.
*/
void
gst_element_remove_pad (GstElement *element, GstPad *pad)
{
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (pad != NULL);
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_PARENT (pad) == element);
/* check to see if the pad is still linked */
/* FIXME: what if someone calls _remove_pad instead of
_remove_ghost_pad? */
if (GST_IS_REAL_PAD (pad)) {
g_return_if_fail (GST_RPAD_PEER (pad) == NULL);
}
/* remove it from the list */
element->pads = g_list_remove (element->pads, pad);
element->numpads--;
if (gst_pad_get_direction (pad) == GST_PAD_SRC)
element->numsrcpads--;
else
element->numsinkpads--;
g_signal_emit (G_OBJECT (element), gst_element_signals[PAD_REMOVED], 0, pad);
gst_object_unparent (GST_OBJECT (pad));
}
/**
* gst_element_add_ghost_pad:
* @element: a #GstElement to add the ghost pad to.
* @pad: the #GstPad from which the new ghost pad will be created.
* @name: the name of the new ghost pad.
*
* Creates a ghost pad from the given pad, and adds it to the list of pads
* for this element.
*
* Returns: the added ghost #GstPad, or NULL, if no ghost pad was created.
*/
GstPad *
gst_element_add_ghost_pad (GstElement *element, GstPad *pad, const gchar *name)
{
GstPad *ghostpad;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (pad != NULL, NULL);
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
/* then check to see if there's already a pad by that name here */
g_return_val_if_fail (gst_object_check_uniqueness (element->pads, name) == TRUE, NULL);
GST_DEBUG (GST_CAT_ELEMENT_PADS,
"creating new ghost pad called %s, from pad %s:%s",
name, GST_DEBUG_PAD_NAME(pad));
ghostpad = gst_ghost_pad_new (name, pad);
/* add it to the list */
GST_DEBUG(GST_CAT_ELEMENT_PADS,"adding ghost pad %s to element %s",
name, GST_ELEMENT_NAME (element));
element->pads = g_list_append (element->pads, ghostpad);
element->numpads++;
/* set the parent of the ghostpad */
gst_object_set_parent (GST_OBJECT (ghostpad), GST_OBJECT (element));
GST_DEBUG(GST_CAT_ELEMENT_PADS,"added ghostpad %s:%s",GST_DEBUG_PAD_NAME(ghostpad));
/* emit the NEW_GHOST_PAD signal */
g_signal_emit (G_OBJECT (element), gst_element_signals[NEW_PAD], 0, ghostpad);
return ghostpad;
}
/**
* gst_element_remove_ghost_pad:
* @element: a #GstElement to remove the ghost pad from.
* @pad: ghost #GstPad to remove.
*
* Removes a ghost pad from an element.
*/
void
gst_element_remove_ghost_pad (GstElement *element, GstPad *pad)
{
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (GST_IS_GHOST_PAD (pad));
/* FIXME this is redundant?
* wingo 10-july-2001: I don't think so, you have to actually remove the pad
* from the element. gst_pad_remove_ghost_pad just removes the ghostpad from
* the real pad's ghost pad list
*/
gst_object_ref (GST_OBJECT (pad));
gst_element_remove_pad (element, pad);
gst_pad_remove_ghost_pad (GST_PAD (GST_PAD_REALIZE (pad)), pad);
gst_object_unref (GST_OBJECT (pad));
}
/**
* gst_element_get_pad:
* @element: a #GstElement to find pad of.
* @name: the name of the pad to retrieve.
*
* Retrieves a pad from the element by name.
*
* Returns: requested #GstPad if found, otherwise NULL.
*/
GstPad*
gst_element_get_pad (GstElement *element, const gchar *name)
{
GstPad *pad;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (name != NULL, NULL);
pad = gst_element_get_static_pad (element, name);
if (!pad)
pad = gst_element_get_request_pad (element, name);
return pad;
}
/**
* gst_element_get_static_pad:
* @element: a #GstElement to find a static pad of.
* @name: the name of the static #GstPad to retrieve.
*
* Retrieves a pad from the element by name. This version only retrieves
* already-existing (i.e. 'static') pads.
*
* Returns: the requested #GstPad if found, otherwise NULL.
*/
GstPad *
gst_element_get_static_pad (GstElement *element, const gchar *name)
{
GList *walk;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (name != NULL, NULL);
walk = element->pads;
while (walk) {
GstPad *pad;
pad = GST_PAD(walk->data);
if (strcmp (GST_PAD_NAME(pad), name) == 0) {
GST_INFO (GST_CAT_ELEMENT_PADS, "found pad %s:%s", GST_DEBUG_PAD_NAME (pad));
return pad;
}
walk = g_list_next (walk);
}
GST_INFO (GST_CAT_ELEMENT_PADS, "no such pad '%s' in element \"%s\"", name, GST_OBJECT_NAME (element));
return NULL;
}
/**
* gst_element_get_request_pad:
* @element: a #GstElement to find a request pad of.
* @name: the name of the request #GstPad to retrieve.
*
* Retrieves a pad from the element by name. This version only retrieves
* request pads.
*
* Returns: requested #GstPad if found, otherwise NULL.
*/
GstPad*
gst_element_get_request_pad (GstElement *element, const gchar *name)
{
GstPadTemplate *templ = NULL;
GstPad *pad;
const gchar *req_name = NULL;
gboolean templ_found = FALSE;
GList *list;
gint n;
const gchar *data;
gchar *str, *endptr = NULL;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (name != NULL, NULL);
if (strstr (name, "%")) {
templ = gst_element_get_pad_template (element, name);
req_name = NULL;
if (templ)
templ_found = TRUE;
} else {
list = gst_element_get_pad_template_list(element);
while (!templ_found && list) {
templ = (GstPadTemplate*) list->data;
if (templ->presence == GST_PAD_REQUEST) {
/* we know that %s and %d are the only possibilities because of sanity
checks in gst_pad_template_new */
GST_DEBUG (GST_CAT_PADS, "comparing %s to %s", name, templ->name_template);
if ((str = strchr (templ->name_template, '%')) &&
strncmp (templ->name_template, name, str - templ->name_template) == 0 &&
strlen (name) > str - templ->name_template) {
data = name + (str - templ->name_template);
if (*(str+1) == 'd') {
/* it's an int */
n = (gint) strtol (data, &endptr, 10);
if (endptr && *endptr == '\0') {
templ_found = TRUE;
req_name = name;
break;
}
} else {
/* it's a string */
templ_found = TRUE;
req_name = name;
break;
}
}
}
list = list->next;
}
}
if (!templ_found)
return NULL;
pad = gst_element_request_pad (element, templ, req_name);
return pad;
}
/**
* gst_element_get_pad_list:
* @element: a #GstElement to get pads of.
*
* Retrieves a list of the pads associated with the element.
*
* Returns: the #GList of pads.
*/
const GList*
gst_element_get_pad_list (GstElement *element)
{
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
/* return the list of pads */
return element->pads;
}
/**
* gst_element_class_add_pad_template:
* @klass: the #GstElementClass to add the pad template to.
* @templ: a #GstPadTemplate to add to the element class.
*
* Adds a padtemplate to an element class.
* This is useful if you have derived a custom bin and wish to provide
* an on-request pad at runtime. Plug-in writers should use
* gst_element_factory_add_pad_template instead.
*/
void
gst_element_class_add_pad_template (GstElementClass *klass,
GstPadTemplate *templ)
{
g_return_if_fail (klass != NULL);
g_return_if_fail (GST_IS_ELEMENT_CLASS (klass));
g_return_if_fail (templ != NULL);
g_return_if_fail (GST_IS_PAD_TEMPLATE (templ));
klass->padtemplates = g_list_append (klass->padtemplates, templ);
klass->numpadtemplates++;
}
/**
* gst_element_get_pad_template_list:
* @element: a #GstElement to get pad templates of.
*
* Retrieves a list of the pad templates associated with the element.
*
* Returns: the #GList of padtemplates.
*/
GList*
gst_element_get_pad_template_list (GstElement *element)
{
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
return GST_ELEMENT_GET_CLASS (element)->padtemplates;
}
/**
* gst_element_get_pad_template:
* @element: a #GstElement to get the pad template of.
* @name: the name of the #GstPadTemplate to get.
*
* Retrieves a padtemplate from this element with the
* given name.
*
* Returns: the #GstPadTemplate with the given name, or NULL if none was found.
* No unreferencing is necessary.
*/
GstPadTemplate*
gst_element_get_pad_template (GstElement *element, const gchar *name)
{
GList *padlist;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (name != NULL, NULL);
padlist = gst_element_get_pad_template_list (element);
while (padlist) {
GstPadTemplate *padtempl = (GstPadTemplate*) padlist->data;
if (!strcmp (padtempl->name_template, name))
return padtempl;
padlist = g_list_next (padlist);
}
return NULL;
}
/**
* gst_element_get_compatible_pad_template:
* @element: a #GstElement to get a compatible pad template for.
* @compattempl: the #GstPadTemplate to find a compatible template for.
*
* Generates a pad template for this element compatible with the given
* template (meaning it is able to link with it).
*
* Returns: the #GstPadTemplate of the element that is compatible with
* the given GstPadTemplate, or NULL if none was found. No unreferencing
* is necessary.
*/
GstPadTemplate*
gst_element_get_compatible_pad_template (GstElement *element,
GstPadTemplate *compattempl)
{
GstPadTemplate *newtempl = NULL;
GList *padlist;
GST_DEBUG (GST_CAT_ELEMENT_PADS, "gst_element_get_compatible_pad_template()");
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (compattempl != NULL, NULL);
padlist = gst_element_get_pad_template_list (element);
while (padlist) {
GstPadTemplate *padtempl = (GstPadTemplate*) padlist->data;
gboolean comp = FALSE;
/* Ignore name
* Ignore presence
* Check direction (must be opposite)
* Check caps
*/
GST_DEBUG (GST_CAT_CAPS, "checking direction and caps");
if (padtempl->direction == GST_PAD_SRC &&
compattempl->direction == GST_PAD_SINK) {
GST_DEBUG (GST_CAT_CAPS, "compatible direction: found src pad template");
comp = gst_caps_is_always_compatible (GST_PAD_TEMPLATE_CAPS (padtempl),
GST_PAD_TEMPLATE_CAPS (compattempl));
GST_DEBUG(GST_CAT_CAPS, "caps are %scompatible", (comp ? "" : "not "));
} else if (padtempl->direction == GST_PAD_SINK &&
compattempl->direction == GST_PAD_SRC) {
GST_DEBUG (GST_CAT_CAPS, "compatible direction: found sink pad template");
comp = gst_caps_is_always_compatible (GST_PAD_TEMPLATE_CAPS (compattempl),
GST_PAD_TEMPLATE_CAPS (padtempl));
GST_DEBUG (GST_CAT_CAPS, "caps are %scompatible", (comp ? "" : "not "));
}
if (comp) {
newtempl = padtempl;
break;
}
padlist = g_list_next (padlist);
}
return newtempl;
}
/**
* gst_element_request_compatible_pad:
* @element: a #GstElement to request a new pad from.
* @templ: the #GstPadTemplate to which the new pad should be able to link.
*
* Requests a new pad from the element. The template will
* be used to decide what type of pad to create. This function
* is typically used for elements with a padtemplate with presence
* GST_PAD_REQUEST.
*
* Returns: the new #GstPad that was created, or NULL if none could be created.
*/
GstPad*
gst_element_request_compatible_pad (GstElement *element, GstPadTemplate *templ)
{
GstPadTemplate *templ_new;
GstPad *pad = NULL;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (templ != NULL, NULL);
templ_new = gst_element_get_compatible_pad_template (element, templ);
if (templ_new != NULL)
pad = gst_element_request_pad (element, templ_new, NULL);
return pad;
}
/**
* gst_element_get_compatible_pad_filtered:
* @element: a #GstElement in which the pad should be found.
* @pad: the #GstPad to find a compatible one for.
* @filtercaps: the #GstCaps to use as a filter.
*
* Looks for an unlinked pad to which the given pad can link to.
* It is not guaranteed that linking the pads will work, though
* it should work in most cases.
*
* Returns: the #GstPad to which a link can be made.
*/
GstPad*
gst_element_get_compatible_pad_filtered (GstElement *element, GstPad *pad,
GstCaps *filtercaps)
{
const GList *pads;
GstPadTemplate *templ;
GstCaps *templcaps;
GstPad *foundpad = NULL;
/* checks */
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (pad != NULL, NULL);
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
/* let's use the real pad */
pad = (GstPad *) GST_PAD_REALIZE (pad);
g_return_val_if_fail (pad != NULL, NULL);
g_return_val_if_fail (GST_RPAD_PEER (pad) == NULL, NULL);
/* try to get an existing unlinked pad */
pads = gst_element_get_pad_list (element);
while (pads) {
GstPad *current = GST_PAD (pads->data);
if ((GST_PAD_PEER (GST_PAD_REALIZE (current)) == NULL) &&
gst_pad_can_link_filtered (pad, current, filtercaps)) {
return current;
}
pads = g_list_next (pads);
}
/* try to create a new one */
/* requesting is a little crazy, we need a template. Let's create one */
if (filtercaps != NULL) {
templcaps = gst_caps_intersect (filtercaps, (GstCaps *) GST_RPAD_CAPS (pad));
if (templcaps == NULL)
return NULL;
} else {
templcaps = gst_pad_get_caps (pad);
}
templ = gst_pad_template_new ((gchar *) GST_PAD_NAME (pad), GST_RPAD_DIRECTION (pad),
GST_PAD_ALWAYS, templcaps, NULL);
foundpad = gst_element_request_compatible_pad (element, templ);
gst_object_unref (GST_OBJECT (templ)); /* this will take care of the caps too */
/* FIXME: this is broken, but it's in here so autoplugging elements that don't
have caps on their source padtemplates (spider) can link... */
if (!foundpad && !filtercaps) {
templ = gst_pad_template_new ((gchar *) GST_PAD_NAME (pad), GST_RPAD_DIRECTION (pad),
GST_PAD_ALWAYS, NULL, NULL);
foundpad = gst_element_request_compatible_pad (element, templ);
gst_object_unref (GST_OBJECT (templ));
}
return foundpad;
}
/**
* gst_element_get_compatible_pad:
* @element: a #GstElement in which the pad should be found.
* @pad: the #GstPad to find a compatible one for.
*
* Looks for an unlinked pad to which the given pad can link to.
* It is not guaranteed that linking the pads will work, though
* it should work in most cases.
*
* Returns: the #GstPad to which a link can be made, or NULL if none
* could be found.
*/
GstPad*
gst_element_get_compatible_pad (GstElement *element, GstPad *pad)
{
return gst_element_get_compatible_pad_filtered (element, pad, NULL);
}
/**
* gst_element_link_pads_filtered:
* @src: a #GstElement containing the source pad.
* @srcpadname: the name of the #GstPad in source element or NULL for any element.
* @dest: the #GstElement containing the destination pad.
* @destpadname: the name of the #GstPad in destination element or NULL for any element.
* @filtercaps: the #GstCaps to use as a filter.
*
* Links the two named pads of the source and destination elements.
* Side effect is that if one of the pads has no parent, it becomes a
* child of the parent of the other element. If they have different
* parents, the link fails.
*
* Returns: TRUE if the pads could be linked.
*/
gboolean
gst_element_link_pads_filtered (GstElement *src, const gchar *srcpadname,
GstElement *dest, const gchar *destpadname,
GstCaps *filtercaps)
{
const GList *srcpads, *destpads, *srctempls, *desttempls, *l;
GstPad *srcpad, *destpad;
GstPadTemplate *srctempl, *desttempl;
/* checks */
g_return_val_if_fail (GST_IS_ELEMENT (src), FALSE);
g_return_val_if_fail (GST_IS_ELEMENT (dest), FALSE);
GST_INFO (GST_CAT_ELEMENT_PADS, "trying to link element %s:%s to element %s:%s",
GST_ELEMENT_NAME (src), srcpadname ? srcpadname : "(any)",
GST_ELEMENT_NAME (dest), destpadname ? destpadname : "(any)");
/* now get the pads we're trying to link and a list of all remaining pads */
if (srcpadname) {
srcpad = gst_element_get_pad (src, srcpadname);
if (!srcpad) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "no pad %s:%s", GST_ELEMENT_NAME (src), srcpadname);
return FALSE;
} else {
if (!(GST_RPAD_DIRECTION (srcpad) == GST_PAD_SRC)) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is no src pad", GST_DEBUG_PAD_NAME (srcpad));
return FALSE;
}
if (GST_PAD_PEER (srcpad) != NULL) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is already linked", GST_DEBUG_PAD_NAME (srcpad));
return FALSE;
}
}
srcpads = NULL;
} else {
srcpads = gst_element_get_pad_list (src);
srcpad = srcpads ? (GstPad *) GST_PAD_REALIZE (srcpads->data) : NULL;
}
if (destpadname) {
destpad = gst_element_get_pad (dest, destpadname);
if (!destpad) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "no pad %s:%s", GST_ELEMENT_NAME (dest), destpadname);
return FALSE;
} else {
if (!(GST_RPAD_DIRECTION (destpad) == GST_PAD_SINK)) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is no sink pad", GST_DEBUG_PAD_NAME (destpad));
return FALSE;
}
if (GST_PAD_PEER (destpad) != NULL) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is already linked", GST_DEBUG_PAD_NAME (destpad));
return FALSE;
}
}
destpads = NULL;
} else {
destpads = gst_element_get_pad_list (dest);
destpad = destpads ? (GstPad *) GST_PAD_REALIZE (destpads->data) : NULL;
}
if (srcpadname && destpadname) {
/* two explicitly specified pads */
return gst_pad_link_filtered (srcpad, destpad, filtercaps);
}
if (srcpad) {
/* loop through the allowed pads in the source, trying to find a
* compatible destination pad */
GST_DEBUG (GST_CAT_ELEMENT_PADS, "looping through allowed src and dest pads");
do {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "trying src pad %s:%s",
GST_DEBUG_PAD_NAME (srcpad));
if ((GST_RPAD_DIRECTION (srcpad) == GST_PAD_SRC) &&
(GST_PAD_PEER (srcpad) == NULL)) {
GstPad *temp = gst_element_get_compatible_pad_filtered (dest, srcpad,
filtercaps);
if (temp && gst_pad_link_filtered (srcpad, temp, filtercaps)) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "linked pad %s:%s to pad %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (temp));
return TRUE;
}
}
/* find a better way for this mess */
if (srcpads) {
srcpads = g_list_next (srcpads);
if (srcpads)
srcpad = (GstPad *) GST_PAD_REALIZE (srcpads->data);
}
} while (srcpads);
}
if (srcpadname) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s:%s to %s",
GST_DEBUG_PAD_NAME (srcpad), GST_ELEMENT_NAME (dest));
return FALSE;
}
if (destpad) {
/* loop through the existing pads in the destination */
do {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "trying dest pad %s:%s",
GST_DEBUG_PAD_NAME (destpad));
if ((GST_RPAD_DIRECTION (destpad) == GST_PAD_SINK) &&
(GST_PAD_PEER (destpad) == NULL)) {
GstPad *temp = gst_element_get_compatible_pad_filtered (src, destpad,
filtercaps);
if (temp && gst_pad_link_filtered (temp, destpad, filtercaps)) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "linked pad %s:%s to pad %s:%s",
GST_DEBUG_PAD_NAME (temp), GST_DEBUG_PAD_NAME (destpad));
return TRUE;
}
}
if (destpads) {
destpads = g_list_next (destpads);
if (destpads)
destpad = (GstPad *) GST_PAD_REALIZE (destpads->data);
}
} while (destpads);
}
if (destpadname) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s to %s:%s",
GST_ELEMENT_NAME (src), GST_DEBUG_PAD_NAME (destpad));
return FALSE;
}
GST_DEBUG (GST_CAT_ELEMENT_PADS,
"we might have request pads on both sides, checking...");
srctempls = gst_element_get_pad_template_list (src);
desttempls = gst_element_get_pad_template_list (dest);
if (srctempls && desttempls) {
while (srctempls) {
srctempl = (GstPadTemplate*) srctempls->data;
if (srctempl->presence == GST_PAD_REQUEST) {
for (l=desttempls; l; l=l->next) {
desttempl = (GstPadTemplate*) desttempls->data;
if (desttempl->presence == GST_PAD_REQUEST &&
desttempl->direction != srctempl->direction) {
if (gst_caps_is_always_compatible (gst_pad_template_get_caps (srctempl),
gst_pad_template_get_caps (desttempl))) {
srcpad = gst_element_get_request_pad (src,
srctempl->name_template);
destpad = gst_element_get_request_pad (dest,
desttempl->name_template);
if (gst_pad_link_filtered (srcpad, destpad, filtercaps)) {
GST_DEBUG (GST_CAT_ELEMENT_PADS,
"linked pad %s:%s to pad %s:%s",
GST_DEBUG_PAD_NAME (srcpad),
GST_DEBUG_PAD_NAME (destpad));
return TRUE;
}
/* FIXME: we have extraneous request pads lying around */
}
}
}
}
srctempls = srctempls->next;
}
}
GST_DEBUG (GST_CAT_ELEMENT_PADS, "no link possible from %s to %s",
GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
return FALSE;
}
/**
* gst_element_link_filtered:
* @src: a #GstElement containing the source pad.
* @dest: the #GstElement containing the destination pad.
* @filtercaps: the #GstCaps to use as a filter.
*
* Links the source to the destination element using the filtercaps.
* The link must be from source to destination, the other
* direction will not be tried.
* The functions looks for existing pads that aren't linked yet.
* It will use request pads if possible. But both pads will not be requested.
* If multiple links are possible, only one is established.
*
* Returns: TRUE if the elements could be linked.
*/
gboolean
gst_element_link_filtered (GstElement *src, GstElement *dest,
GstCaps *filtercaps)
{
return gst_element_link_pads_filtered (src, NULL, dest, NULL, filtercaps);
}
/**
* gst_element_link_many:
* @element_1: the first #GstElement in the link chain.
* @element_2: the second #GstElement in the link chain.
* @...: the NULL-terminated list of elements to link in order.
*
* Chain together a series of elements. Uses #gst_element_link.
*
* Returns: TRUE on success, FALSE otherwise.
*/
gboolean
gst_element_link_many (GstElement *element_1, GstElement *element_2, ...)
{
va_list args;
g_return_val_if_fail (element_1 != NULL && element_2 != NULL, FALSE);
g_return_val_if_fail (GST_IS_ELEMENT (element_1) &&
GST_IS_ELEMENT (element_2), FALSE);
va_start (args, element_2);
while (element_2) {
if (!gst_element_link (element_1, element_2))
return FALSE;
element_1 = element_2;
element_2 = va_arg (args, GstElement*);
}
va_end (args);
return TRUE;
}
/**
* gst_element_link:
* @src: a #GstElement containing the source pad.
* @dest: the #GstElement containing the destination pad.
*
* Links the source to the destination element.
* The link must be from source to destination, the other
* direction will not be tried.
* The functions looks for existing pads and request pads that aren't
* linked yet. If multiple links are possible, only one is
* established.
*
* Returns: TRUE if the elements could be linked.
*/
gboolean
gst_element_link (GstElement *src, GstElement *dest)
{
return gst_element_link_pads_filtered (src, NULL, dest, NULL, NULL);
}
/**
* gst_element_link_pads:
* @src: a #GstElement containing the source pad.
* @srcpadname: the name of the #GstPad in the source element.
* @dest: the #GstElement containing the destination pad.
* @destpadname: the name of the #GstPad in destination element.
*
* Links the two named pads of the source and destination elements.
* Side effect is that if one of the pads has no parent, it becomes a
* child of the parent of the other element. If they have different
* parents, the link fails.
*
* Returns: TRUE if the pads could be linked.
*/
gboolean
gst_element_link_pads (GstElement *src, const gchar *srcpadname,
GstElement *dest, const gchar *destpadname)
{
return gst_element_link_pads_filtered (src, srcpadname, dest, destpadname, NULL);
}
/**
* gst_element_unlink_pads:
* @src: a #GstElement containing the source pad.
* @srcpadname: the name of the #GstPad in source element.
* @dest: a #GstElement containing the destination pad.
* @destpadname: the name of the #GstPad in destination element.
*
* Unlinks the two named pads of the source and destination elements.
*/
void
gst_element_unlink_pads (GstElement *src, const gchar *srcpadname,
GstElement *dest, const gchar *destpadname)
{
GstPad *srcpad,*destpad;
g_return_if_fail (src != NULL);
g_return_if_fail (GST_IS_ELEMENT(src));
g_return_if_fail (srcpadname != NULL);
g_return_if_fail (dest != NULL);
g_return_if_fail (GST_IS_ELEMENT(dest));
g_return_if_fail (destpadname != NULL);
/* obtain the pads requested */
srcpad = gst_element_get_pad (src, srcpadname);
if (srcpad == NULL) {
GST_ERROR(src,"source element has no pad \"%s\"",srcpadname);
return;
}
destpad = gst_element_get_pad (dest, destpadname);
if (srcpad == NULL) {
GST_ERROR(dest,"destination element has no pad \"%s\"",destpadname);
return;
}
/* we're satisified they can be unlinked, let's do it */
gst_pad_unlink (srcpad,destpad);
}
/**
* gst_element_unlink_many:
* @element_1: the first #GstElement in the link chain.
* @element_2: the second #GstElement in the link chain.
* @...: the NULL-terminated list of elements to unlink in order.
*
* Unlinks a series of elements. Uses #gst_element_unlink.
*/
void
gst_element_unlink_many (GstElement *element_1, GstElement *element_2, ...)
{
va_list args;
g_return_if_fail (element_1 != NULL && element_2 != NULL);
g_return_if_fail (GST_IS_ELEMENT (element_1) && GST_IS_ELEMENT (element_2));
va_start (args, element_2);
while (element_2) {
gst_element_unlink (element_1, element_2);
element_1 = element_2;
element_2 = va_arg (args, GstElement*);
}
va_end (args);
}
/**
* gst_element_unlink:
* @src: the source #GstElement to unlink.
* @dest: the sink #GstElement to unlink.
*
* Unlinks all source pads of the source element with all sink pads
* of the sink element to which they are linked.
*/
void
gst_element_unlink (GstElement *src, GstElement *dest)
{
const GList *srcpads;
GstPad *pad;
g_return_if_fail (GST_IS_ELEMENT (src));
g_return_if_fail (GST_IS_ELEMENT (dest));
GST_DEBUG (GST_CAT_ELEMENT_PADS, "unlinking \"%s\" and \"%s\"",
GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
srcpads = gst_element_get_pad_list (src);
while (srcpads) {
pad = GST_PAD_CAST (srcpads->data);
/* we only care about real src pads */
if (GST_IS_REAL_PAD (pad) && GST_PAD_IS_SRC (pad)) {
GstPad *peerpad = GST_PAD_PEER (pad);
/* see if the pad is connected and is really a pad
* of dest */
if (peerpad &&
(GST_OBJECT_PARENT (peerpad) == (GstObject*) dest))
{
gst_pad_unlink (pad, peerpad);
}
}
srcpads = g_list_next (srcpads);
}
}
static void
gst_element_error_func (GstElement* element, GstElement *source,
gchar *errormsg)
{
/* tell the parent */
if (GST_OBJECT_PARENT (element)) {
GST_DEBUG (GST_CAT_EVENT, "forwarding error \"%s\" from %s to %s",
errormsg, GST_ELEMENT_NAME (element),
GST_OBJECT_NAME (GST_OBJECT_PARENT (element)));
gst_object_ref (GST_OBJECT (element));
g_signal_emit (G_OBJECT (GST_OBJECT_PARENT (element)),
gst_element_signals[ERROR], 0, source, errormsg);
gst_object_unref (GST_OBJECT (element));
}
}
static GstPad*
gst_element_get_random_pad (GstElement *element, GstPadDirection dir)
{
GList *pads = element->pads;
GST_DEBUG (GST_CAT_ELEMENT_PADS, "getting a random pad");
while (pads) {
GstPad *pad = GST_PAD_CAST (pads->data);
GST_DEBUG (GST_CAT_ELEMENT_PADS, "checking pad %s:%s",
GST_DEBUG_PAD_NAME (pad));
if (GST_PAD_DIRECTION (pad) == dir) {
if (GST_PAD_IS_LINKED (pad)) {
return pad;
}
else {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is not linked",
GST_DEBUG_PAD_NAME (pad));
}
}
else {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "pad %s:%s is in wrong direction",
GST_DEBUG_PAD_NAME (pad));
}
pads = g_list_next (pads);
}
return NULL;
}
/**
* gst_element_get_event_masks:
* @element: a #GstElement to query
*
* Get an array of event masks from the element.
* If the element doesn't
* implement an event masks function, the query will be forwarded
* to a random linked sink pad.
*
* Returns: An array of #GstEventMask elements.
*/
const GstEventMask*
gst_element_get_event_masks (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->get_event_masks)
return oclass->get_event_masks (element);
else {
GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK);
if (pad)
return gst_pad_get_event_masks (GST_PAD_PEER (pad));
}
return FALSE;
}
/**
* gst_element_send_event:
* @element: a #GstElement to send the event to.
* @event: the #GstEvent to send to the element.
*
* Sends an event to an element. If the element doesn't
* implement an event handler, the event will be forwarded
* to a random sink pad.
*
* Returns: TRUE if the event was handled.
*/
gboolean
gst_element_send_event (GstElement *element, GstEvent *event)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->send_event)
return oclass->send_event (element, event);
else {
GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK);
if (pad) {
GST_DEBUG (GST_CAT_ELEMENT_PADS, "sending event to random pad %s:%s",
GST_DEBUG_PAD_NAME (pad));
return gst_pad_send_event (GST_PAD_PEER (pad), event);
}
}
GST_DEBUG (GST_CAT_ELEMENT_PADS, "can't send event on element %s",
GST_ELEMENT_NAME (element));
return FALSE;
}
/**
* gst_element_get_query_types:
* @element: a #GstElement to query
*
* Get an array of query types from the element.
* If the element doesn't
* implement a query types function, the query will be forwarded
* to a random sink pad.
*
* Returns: An array of #GstQueryType elements.
*/
const GstQueryType*
gst_element_get_query_types (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->get_query_types)
return oclass->get_query_types (element);
else {
GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK);
if (pad)
return gst_pad_get_query_types (GST_PAD_PEER (pad));
}
return FALSE;
}
/**
* gst_element_query:
* @element: a #GstElement to perform the query on.
* @type: the #GstQueryType.
* @format: the #GstFormat pointer to hold the format of the result.
* @value: the pointer to the value of the result.
*
* Performs a query on the given element. If the format is set
* to GST_FORMAT_DEFAULT and this function returns TRUE, the
* format pointer will hold the default format.
* For element that don't implement a query handler, this function
* forwards the query to a random usable sinkpad of this element.
*
* Returns: TRUE if the query could be performed.
*/
gboolean
gst_element_query (GstElement *element, GstQueryType type,
GstFormat *format, gint64 *value)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
g_return_val_if_fail (format != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->query)
return oclass->query (element, type, format, value);
else {
GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK);
if (pad)
return gst_pad_query (GST_PAD_PEER (pad), type, format, value);
}
return FALSE;
}
/**
* gst_element_get_formats:
* @element: a #GstElement to query
*
* Get an array of formst from the element.
* If the element doesn't
* implement a formats function, the query will be forwarded
* to a random sink pad.
*
* Returns: An array of #GstFormat elements.
*/
const GstFormat*
gst_element_get_formats (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->get_formats)
return oclass->get_formats (element);
else {
GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK);
if (pad)
return gst_pad_get_formats (GST_PAD_PEER (pad));
}
return FALSE;
}
/**
* gst_element_convert:
* @element: a #GstElement to invoke the converter on.
* @src_format: the source #GstFormat.
* @src_value: the source value.
* @dest_format: a pointer to the destination #GstFormat.
* @dest_value: a pointer to the destination value.
*
* Invokes a conversion on the element.
* If the element doesn't
* implement a convert function, the query will be forwarded
* to a random sink pad.
*
* Returns: TRUE if the conversion could be performed.
*/
gboolean
gst_element_convert (GstElement *element,
GstFormat src_format, gint64 src_value,
GstFormat *dest_format, gint64 *dest_value)
{
GstElementClass *oclass;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
g_return_val_if_fail (dest_format != NULL, FALSE);
g_return_val_if_fail (dest_value != NULL, FALSE);
if (src_format == *dest_format) {
*dest_value = src_value;
return TRUE;
}
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->convert)
return oclass->convert (element,
src_format, src_value,
dest_format, dest_value);
else {
GstPad *pad = gst_element_get_random_pad (element, GST_PAD_SINK);
if (pad)
return gst_pad_convert (GST_PAD_PEER (pad),
src_format, src_value,
dest_format, dest_value);
}
return FALSE;
}
/**
* gst_element_error:
* @element: a #GstElement with the error.
* @error: the printf-style string describing the error.
* @...: the optional arguments for the string.
*
* signals an error condition on an element.
* This function is used internally by elements.
* It results in the "error" signal.
*/
void
gst_element_error (GstElement *element, const gchar *error, ...)
{
va_list var_args;
gchar *string;
/* checks */
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (error != NULL);
/* create error message */
va_start (var_args, error);
string = g_strdup_vprintf (error, var_args);
va_end (var_args);
GST_INFO (GST_CAT_EVENT, "ERROR in %s: %s", GST_ELEMENT_NAME (element), string);
/* emit the signal, make sure the element stays available */
gst_object_ref (GST_OBJECT (element));
g_signal_emit (G_OBJECT (element), gst_element_signals[ERROR], 0, element, string);
/* tell the scheduler */
if (element->sched) {
gst_scheduler_error (element->sched, element);
}
if (GST_STATE (element) == GST_STATE_PLAYING)
gst_element_set_state (element, GST_STATE_PAUSED);
/* cleanup */
gst_object_unref (GST_OBJECT (element));
g_free (string);
}
/**
* gst_element_is_locked_state:
* @element: a #GstElement.
*
* Checks if the state of an element is locked.
* If the state of an element is locked, state changes of the parent don't
* affect the element.
* This way you can leave currently unused elements inside bins. Just lock their
* state before changing the state from #GST_STATE_NULL.
*
* Returns: TRUE, if the element's state is locked.
*/
gboolean
gst_element_is_locked_state (GstElement *element)
{
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
return GST_FLAG_IS_SET (element, GST_ELEMENT_LOCKED_STATE) ? TRUE : FALSE;
}
/**
* gst_element_set_locked_state:
* @element: a #GstElement
* @locked_state: TRUE to lock the element's state
*
* Locks the state of an element, so state changes of the parent don't affect
* this element anymore.
*/
void
gst_element_set_locked_state (GstElement *element, gboolean locked_state)
{
gboolean old;
g_return_if_fail (GST_IS_ELEMENT (element));
old = GST_FLAG_IS_SET (element, GST_ELEMENT_LOCKED_STATE);
if (old == locked_state)
return;
if (locked_state) {
GST_DEBUG (GST_CAT_STATES, "locking state of element %s",
GST_ELEMENT_NAME (element));
GST_FLAG_SET (element, GST_ELEMENT_LOCKED_STATE);
} else {
GST_DEBUG (GST_CAT_STATES, "unlocking state of element %s",
GST_ELEMENT_NAME (element));
GST_FLAG_UNSET (element, GST_ELEMENT_LOCKED_STATE);
}
}
/**
* gst_element_sync_state_with_parent:
* @element: a #GstElement.
*
* Tries to change the state of the element to the same as its parent.
* If this function returns FALSE, the state of element is undefined.
*
* Returns: TRUE, if the element's state could be synced to the parent's state.
*/
gboolean
gst_element_sync_state_with_parent (GstElement *element)
{
GstElement *parent;
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
parent = GST_ELEMENT (GST_ELEMENT_PARENT(element));
g_return_val_if_fail (GST_IS_BIN (parent), FALSE);
GST_DEBUG (GST_CAT_STATES, "syncing state of element %s (%s) to %s (%s)",
GST_ELEMENT_NAME (element), gst_element_state_get_name (GST_STATE (element)),
GST_ELEMENT_NAME (parent), gst_element_state_get_name (GST_STATE (parent)));
if (gst_element_set_state (element, GST_STATE (parent)) == GST_STATE_FAILURE) {
return FALSE;
}
return TRUE;
}
/**
* gst_element_get_state:
* @element: a #GstElement to get the state of.
*
* Gets the state of the element.
*
* Returns: the #GstElementState of the element.
*/
GstElementState
gst_element_get_state (GstElement *element)
{
g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_VOID_PENDING);
return GST_STATE (element);
}
/**
* gst_element_wait_state_change:
* @element: a #GstElement to wait for a state change on.
*
* Waits and blocks until the element changed its state.
*/
void
gst_element_wait_state_change (GstElement *element)
{
g_mutex_lock (element->state_mutex);
g_cond_wait (element->state_cond, element->state_mutex);
g_mutex_unlock (element->state_mutex);
}
/**
* gst_element_set_state:
* @element: a #GstElement to change state of.
* @state: the element's new #GstElementState.
*
* Sets the state of the element. This function will try to set the
* requested state by going through all the intermediary states and calling
* the class's state change function for each.
*
* Returns: TRUE if the state was successfully set.
* (using #GstElementStateReturn).
*/
GstElementStateReturn
gst_element_set_state (GstElement *element, GstElementState state)
{
GstElementClass *oclass;
GstElementState curpending;
GstElementStateReturn return_val = GST_STATE_SUCCESS;
g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_FAILURE);
/* start with the current state */
curpending = GST_STATE(element);
GST_DEBUG_ELEMENT (GST_CAT_STATES, element, "setting state from %s to %s",
gst_element_state_get_name (curpending),
gst_element_state_get_name (state));
/* loop until the final requested state is set */
while (GST_STATE (element) != state
&& GST_STATE (element) != GST_STATE_VOID_PENDING) {
/* move the curpending state in the correct direction */
if (curpending < state)
curpending <<= 1;
else
curpending >>= 1;
/* set the pending state variable */
/* FIXME: should probably check to see that we don't already have one */
GST_STATE_PENDING (element) = curpending;
if (curpending != state) {
GST_DEBUG_ELEMENT (GST_CAT_STATES, element,
"intermediate: setting state from %s to %s",
gst_element_state_get_name (GST_STATE (element)),
gst_element_state_get_name (curpending));
}
/* call the state change function so it can set the state */
oclass = GST_ELEMENT_GET_CLASS (element);
if (oclass->change_state)
return_val = (oclass->change_state) (element);
switch (return_val) {
case GST_STATE_FAILURE:
GST_DEBUG_ELEMENT (GST_CAT_STATES, element,
"have failed change_state return");
goto exit;
case GST_STATE_ASYNC:
GST_DEBUG_ELEMENT (GST_CAT_STATES, element,
"element will change state async");
goto exit;
case GST_STATE_SUCCESS:
/* Last thing we do is verify that a successful state change really
* did change the state... */
/* if it did not, this is an error - fix the element that does this */
if (GST_STATE (element) != curpending) {
g_warning ("element %s claimed state-change success,"
"but state didn't change to %s. State is %s (%s pending), fix the element",
GST_ELEMENT_NAME (element),
gst_element_state_get_name (curpending),
gst_element_state_get_name (GST_STATE (element)),
gst_element_state_get_name (GST_STATE_PENDING (element)));
return_val = GST_STATE_FAILURE;
goto exit;
}
break;
default:
/* somebody added a GST_STATE_ and forgot to do stuff here ! */
g_assert_not_reached ();
}
}
exit:
/* signal the state change in case somebody is waiting for us */
g_mutex_lock (element->state_mutex);
g_cond_signal (element->state_cond);
g_mutex_unlock (element->state_mutex);
return return_val;
}
static gboolean
gst_element_negotiate_pads (GstElement *element)
{
GList *pads = GST_ELEMENT_PADS (element);
GST_DEBUG_ELEMENT (GST_CAT_CAPS, element, "negotiating pads");
while (pads) {
GstPad *pad = GST_PAD (pads->data);
GstRealPad *srcpad;
pads = g_list_next (pads);
if (!GST_IS_REAL_PAD (pad))
continue;
srcpad = GST_PAD_REALIZE (pad);
/* if we have a link on this pad and it doesn't have caps
* allready, try to negotiate */
if (GST_PAD_IS_LINKED (srcpad) && !GST_PAD_CAPS (srcpad)) {
GstRealPad *sinkpad;
GstElementState otherstate;
GstElement *parent;
sinkpad = GST_RPAD_PEER (GST_PAD_REALIZE (srcpad));
/* check the parent of the peer pad, if there is no parent do nothing */
parent = GST_PAD_PARENT (sinkpad);
if (!parent)
continue;
/* skips pads that were already negotiating */
if (GST_FLAG_IS_SET (sinkpad, GST_PAD_NEGOTIATING) ||
GST_FLAG_IS_SET (srcpad, GST_PAD_NEGOTIATING))
continue;
otherstate = GST_STATE (parent);
/* swap pads if needed */
if (!GST_PAD_IS_SRC (srcpad)) {
GstRealPad *temp;
temp = srcpad;
srcpad = sinkpad;
sinkpad = temp;
}
/* only try to negotiate if the peer element is in PAUSED or higher too */
if (otherstate >= GST_STATE_READY) {
GST_DEBUG_ELEMENT (GST_CAT_CAPS, element,
"perform negotiate for %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad),
GST_DEBUG_PAD_NAME (sinkpad));
if (!gst_pad_perform_negotiate (GST_PAD (srcpad), GST_PAD (sinkpad)))
return FALSE;
}
else {
GST_DEBUG_ELEMENT (GST_CAT_CAPS, element,
"not negotiating %s:%s and %s:%s, not in READY yet",
GST_DEBUG_PAD_NAME (srcpad),
GST_DEBUG_PAD_NAME (sinkpad));
}
}
}
return TRUE;
}
static void
gst_element_clear_pad_caps (GstElement *element)
{
GList *pads = GST_ELEMENT_PADS (element);
GST_DEBUG_ELEMENT (GST_CAT_CAPS, element, "clearing pad caps");
while (pads) {
GstRealPad *pad = GST_PAD_REALIZE (pads->data);
gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
pads = g_list_next (pads);
}
}
static void
gst_element_pads_activate (GstElement *element, gboolean active)
{
GList *pads = element->pads;
while (pads) {
GstPad *pad = GST_PAD_CAST (pads->data);
pads = g_list_next (pads);
if (!GST_IS_REAL_PAD (pad))
continue;
gst_pad_set_active (pad, active);
}
}
static GstElementStateReturn
gst_element_change_state (GstElement *element)
{
GstElementState old_state;
GstObject *parent;
gint old_pending, old_transition;
g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_FAILURE);
old_state = GST_STATE (element);
old_pending = GST_STATE_PENDING (element);
old_transition = GST_STATE_TRANSITION (element);
if (old_pending == GST_STATE_VOID_PENDING ||
old_state == GST_STATE_PENDING (element)) {
GST_INFO (GST_CAT_STATES,
"no state change needed for element %s (VOID_PENDING)",
GST_ELEMENT_NAME (element));
return GST_STATE_SUCCESS;
}
GST_INFO (GST_CAT_STATES, "%s default handler sets state from %s to %s %04x",
GST_ELEMENT_NAME (element),
gst_element_state_get_name (old_state),
gst_element_state_get_name (old_pending),
old_transition);
/* we set the state change early for the negotiation functions */
GST_STATE (element) = old_pending;
GST_STATE_PENDING (element) = GST_STATE_VOID_PENDING;
switch (old_transition) {
case GST_STATE_PLAYING_TO_PAUSED:
gst_element_pads_activate (element, FALSE);
break;
case GST_STATE_PAUSED_TO_PLAYING:
gst_element_pads_activate (element, TRUE);
break;
/* if we are going to paused, we try to negotiate the pads */
case GST_STATE_READY_TO_PAUSED:
if (!gst_element_negotiate_pads (element))
goto failure;
break;
/* going to the READY state clears all pad caps */
case GST_STATE_PAUSED_TO_READY:
gst_element_clear_pad_caps (element);
break;
default:
break;
}
parent = GST_ELEMENT_PARENT (element);
GST_DEBUG_ELEMENT (GST_CAT_STATES, element,
"signaling state change from %s to %s",
gst_element_state_get_name (old_state),
gst_element_state_get_name (GST_STATE (element)));
/* tell the scheduler if we have one */
if (element->sched) {
if (gst_scheduler_state_transition (element->sched, element,
old_transition) != GST_STATE_SUCCESS) {
GST_DEBUG_ELEMENT (GST_CAT_STATES, element,
"scheduler could change state");
goto failure;
}
}
g_signal_emit (G_OBJECT (element), gst_element_signals[STATE_CHANGE],
0, old_state, GST_STATE (element));
/* tell our parent about the state change */
if (parent && GST_IS_BIN (parent)) {
gst_bin_child_state_change (GST_BIN (parent), old_state,
GST_STATE (element), element);
}
return GST_STATE_SUCCESS;
failure:
/* undo the state change */
GST_STATE (element) = old_state;
GST_STATE_PENDING (element) = old_pending;
return GST_STATE_FAILURE;
}
/**
* gst_element_get_factory:
* @element: a #GstElement to request the element factory of.
*
* Retrieves the factory that was used to create this element.
*
* Returns: the #GstElementFactory used for creating this element.
*/
GstElementFactory*
gst_element_get_factory (GstElement *element)
{
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
return GST_ELEMENT_GET_CLASS (element)->elementfactory;
}
static void
gst_element_dispose (GObject *object)
{
GstElement *element = GST_ELEMENT (object);
GList *pads;
GstPad *pad;
GST_DEBUG_ELEMENT (GST_CAT_REFCOUNTING, element, "dispose");
gst_element_set_state (element, GST_STATE_NULL);
/* first we break all our links with the ouside */
if (element->pads) {
GList *orig;
orig = pads = g_list_copy (element->pads);
while (pads) {
pad = GST_PAD (pads->data);
if (GST_PAD_PEER (pad)) {
GST_DEBUG (GST_CAT_REFCOUNTING, "unlinking pad '%s'",
GST_OBJECT_NAME (GST_OBJECT (GST_PAD (GST_PAD_PEER (pad)))));
gst_pad_unlink (pad, GST_PAD (GST_PAD_PEER (pad)));
}
gst_element_remove_pad (element, pad);
pads = g_list_next (pads);
}
g_list_free (orig);
g_list_free (element->pads);
element->pads = NULL;
}
element->numsrcpads = 0;
element->numsinkpads = 0;
element->numpads = 0;
g_mutex_free (element->state_mutex);
g_cond_free (element->state_cond);
if (element->prop_value_queue)
g_async_queue_unref (element->prop_value_queue);
element->prop_value_queue = NULL;
if (element->property_mutex)
g_mutex_free (element->property_mutex);
gst_object_replace ((GstObject **)&element->sched, NULL);
gst_object_replace ((GstObject **)&element->clock, NULL);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
#ifndef GST_DISABLE_LOADSAVE
/**
* gst_element_save_thyself:
* @element: a #GstElement to save.
* @parent: the xml parent node.
*
* Saves the element as part of the given XML structure.
*
* Returns: the new #xmlNodePtr.
*/
static xmlNodePtr
gst_element_save_thyself (GstObject *object,
xmlNodePtr parent)
{
GList *pads;
GstElementClass *oclass;
GParamSpec **specs, *spec;
gint nspecs, i;
GValue value = { 0, };
GstElement *element;
g_return_val_if_fail (GST_IS_ELEMENT (object), parent);
element = GST_ELEMENT (object);
oclass = GST_ELEMENT_GET_CLASS (element);
xmlNewChild(parent, NULL, "name", GST_ELEMENT_NAME(element));
if (oclass->elementfactory != NULL) {
GstElementFactory *factory = (GstElementFactory *)oclass->elementfactory;
xmlNewChild (parent, NULL, "type", GST_OBJECT_NAME (factory));
xmlNewChild (parent, NULL, "version", factory->details->version);
}
/* FIXME: what is this? */
/* if (element->manager) */
/* xmlNewChild(parent, NULL, "manager", GST_ELEMENT_NAME(element->manager)); */
/* params */
specs = g_object_class_list_properties (G_OBJECT_GET_CLASS (object), &nspecs);
for (i=0; i<nspecs; i++) {
spec = specs[i];
if (spec->flags & G_PARAM_READABLE) {
xmlNodePtr param;
char *contents;
g_value_init(&value, G_PARAM_SPEC_VALUE_TYPE (spec));
g_object_get_property (G_OBJECT (element), spec->name, &value);
param = xmlNewChild (parent, NULL, "param", NULL);
xmlNewChild (param, NULL, "name", spec->name);
if (G_IS_PARAM_SPEC_STRING (spec))
contents = g_value_dup_string (&value);
else if (G_IS_PARAM_SPEC_ENUM (spec))
contents = g_strdup_printf ("%d", g_value_get_enum (&value));
else if (G_IS_PARAM_SPEC_INT64 (spec))
contents = g_strdup_printf ("%" G_GINT64_FORMAT,
g_value_get_int64 (&value));
else
contents = g_strdup_value_contents (&value);
xmlNewChild (param, NULL, "value", contents);
g_free (contents);
g_value_unset(&value);
}
}
pads = GST_ELEMENT_PADS (element);
while (pads) {
GstPad *pad = GST_PAD (pads->data);
/* figure out if it's a direct pad or a ghostpad */
if (GST_ELEMENT (GST_OBJECT_PARENT (pad)) == element) {
xmlNodePtr padtag = xmlNewChild (parent, NULL, "pad", NULL);
gst_object_save_thyself (GST_OBJECT (pad), padtag);
}
pads = g_list_next (pads);
}
return parent;
}
static void
gst_element_restore_thyself (GstObject *object, xmlNodePtr self)
{
xmlNodePtr children;
GstElement *element;
gchar *name = NULL;
gchar *value = NULL;
element = GST_ELEMENT (object);
g_return_if_fail (element != NULL);
/* parameters */
children = self->xmlChildrenNode;
while (children) {
if (!strcmp (children->name, "param")) {
xmlNodePtr child = children->xmlChildrenNode;
while (child) {
if (!strcmp (child->name, "name")) {
name = xmlNodeGetContent (child);
}
else if (!strcmp (child->name, "value")) {
value = xmlNodeGetContent (child);
}
child = child->next;
}
/* FIXME: can this just be g_object_set ? */
gst_util_set_object_arg (G_OBJECT (element), name, value);
}
children = children->next;
}
/* pads */
children = self->xmlChildrenNode;
while (children) {
if (!strcmp (children->name, "pad")) {
gst_pad_load_and_link (children, GST_OBJECT (element));
}
children = children->next;
}
if (GST_OBJECT_CLASS (parent_class)->restore_thyself)
(GST_OBJECT_CLASS (parent_class)->restore_thyself) (object, self);
}
#endif /* GST_DISABLE_LOADSAVE */
/**
* gst_element_yield:
* @element: a #GstElement to yield.
*
* Requests a yield operation for the element. The scheduler will typically
* give control to another element.
*/
void
gst_element_yield (GstElement *element)
{
if (GST_ELEMENT_SCHED (element)) {
gst_scheduler_yield (GST_ELEMENT_SCHED (element), element);
}
}
/**
* gst_element_interrupt:
* @element: a #GstElement to interrupt.
*
* Requests the scheduler of this element to interrupt the execution of
* this element and scheduler another one.
*
* Returns: TRUE if the element should exit its chain/loop/get
* function ASAP, depending on the scheduler implementation.
*/
gboolean
gst_element_interrupt (GstElement *element)
{
if (GST_ELEMENT_SCHED (element)) {
return gst_scheduler_interrupt (GST_ELEMENT_SCHED (element), element);
}
else
return TRUE;
}
/**
* gst_element_set_scheduler:
* @element: a #GstElement to set the scheduler of.
* @sched: the #GstScheduler to set.
*
* Sets the scheduler of the element. For internal use only, unless you're
* writing a new bin subclass.
*/
void
gst_element_set_scheduler (GstElement *element,
GstScheduler *sched)
{
g_return_if_fail (GST_IS_ELEMENT (element));
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, element, "setting scheduler to %p", sched);
gst_object_replace ((GstObject **)&GST_ELEMENT_SCHED (element), GST_OBJECT (sched));
}
/**
* gst_element_get_scheduler:
* @element: a #GstElement to get the scheduler of.
*
* Returns the scheduler of the element.
*
* Returns: the element's #GstScheduler.
*/
GstScheduler*
gst_element_get_scheduler (GstElement *element)
{
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
return GST_ELEMENT_SCHED (element);
}
/**
* gst_element_set_loop_function:
* @element: a #GstElement to set the loop function of.
* @loop: Pointer to #GstElementLoopFunction.
*
* This sets the loop function for the element. The function pointed to
* can deviate from the GstElementLoopFunction definition in type of
* pointer only.
*
* NOTE: in order for this to take effect, the current loop function *must*
* exit. Assuming the loop function itself is the only one who will cause
* a new loopfunc to be assigned, this should be no problem.
*/
void
gst_element_set_loop_function (GstElement *element,
GstElementLoopFunction loop)
{
gboolean need_notify = FALSE;
g_return_if_fail (GST_IS_ELEMENT (element));
/* if the element changed from loop based to chain/get based
* or vice versa, we need to inform the scheduler about that */
if ((element->loopfunc == NULL && loop != NULL) ||
(element->loopfunc != NULL && loop == NULL))
{
need_notify = TRUE;
}
/* set the loop function */
element->loopfunc = loop;
if (need_notify) {
/* set the NEW_LOOPFUNC flag so everyone knows to go try again */
GST_FLAG_SET (element, GST_ELEMENT_NEW_LOOPFUNC);
if (GST_ELEMENT_SCHED (element)) {
gst_scheduler_scheduling_change (GST_ELEMENT_SCHED (element), element);
}
}
}
static inline void
gst_element_set_eos_recursive (GstElement *element)
{
/* this function is only called, when we were in PLAYING before. So every
parent that's PAUSED was PLAYING before. That means it has reached EOS. */
GstElement *parent;
GST_DEBUG (GST_CAT_EVENT, "setting recursive EOS on %s",
GST_OBJECT_NAME (element));
g_signal_emit (G_OBJECT (element), gst_element_signals[EOS], 0);
if (!GST_OBJECT_PARENT (element))
return;
parent = GST_ELEMENT (GST_OBJECT_PARENT (element));
if (GST_STATE (parent) == GST_STATE_PAUSED)
gst_element_set_eos_recursive (parent);
}
/**
* gst_element_set_eos:
* @element: a #GstElement to set to the EOS state.
*
* Perform the actions needed to bring the element in the EOS state.
*/
void
gst_element_set_eos (GstElement *element)
{
g_return_if_fail (GST_IS_ELEMENT (element));
GST_DEBUG (GST_CAT_EVENT, "setting EOS on element %s",
GST_OBJECT_NAME (element));
if (GST_STATE (element) == GST_STATE_PLAYING) {
gst_element_set_state (element, GST_STATE_PAUSED);
gst_element_set_eos_recursive (element);
} else {
g_signal_emit (G_OBJECT (element), gst_element_signals[EOS], 0);
}
}
/**
* gst_element_state_get_name:
* @state: a #GstElementState to get the name of.
*
* Gets a string representing the given state.
*
* Returns: a string with the name of the state.
*/
const gchar*
gst_element_state_get_name (GstElementState state)
{
switch (state) {
#ifdef GST_DEBUG_COLOR
case GST_STATE_VOID_PENDING: return "NONE_PENDING";break;
case GST_STATE_NULL: return "\033[01;37mNULL\033[00m";break;
case GST_STATE_READY: return "\033[01;31mREADY\033[00m";break;
case GST_STATE_PLAYING: return "\033[01;32mPLAYING\033[00m";break;
case GST_STATE_PAUSED: return "\033[01;33mPAUSED\033[00m";break;
default:
/* This is a memory leak */
return g_strdup_printf ("\033[01;37;41mUNKNOWN!\033[00m(%d)", state);
#else
case GST_STATE_VOID_PENDING: return "NONE_PENDING";break;
case GST_STATE_NULL: return "NULL";break;
case GST_STATE_READY: return "READY";break;
case GST_STATE_PLAYING: return "PLAYING";break;
case GST_STATE_PAUSED: return "PAUSED";break;
default: return "UNKNOWN!";
#endif
}
return "";
}
static void
gst_element_populate_std_props (GObjectClass * klass, const gchar *prop_name,
guint arg_id, GParamFlags flags)
{
GQuark prop_id = g_quark_from_string (prop_name);
GParamSpec *pspec;
static GQuark fd_id = 0;
static GQuark blocksize_id;
static GQuark bytesperread_id;
static GQuark dump_id;
static GQuark filesize_id;
static GQuark mmapsize_id;
static GQuark location_id;
static GQuark offset_id;
static GQuark silent_id;
static GQuark touch_id;
if (!fd_id) {
fd_id = g_quark_from_static_string ("fd");
blocksize_id = g_quark_from_static_string ("blocksize");
bytesperread_id = g_quark_from_static_string ("bytesperread");
dump_id = g_quark_from_static_string ("dump");
filesize_id = g_quark_from_static_string ("filesize");
mmapsize_id = g_quark_from_static_string ("mmapsize");
location_id = g_quark_from_static_string ("location");
offset_id = g_quark_from_static_string ("offset");
silent_id = g_quark_from_static_string ("silent");
touch_id = g_quark_from_static_string ("touch");
}
if (prop_id == fd_id) {
pspec = g_param_spec_int ("fd", "File-descriptor",
"File-descriptor for the file being read",
0, G_MAXINT, 0, flags);
}
else if (prop_id == blocksize_id) {
pspec = g_param_spec_ulong ("blocksize", "Block Size",
"Block size to read per buffer",
0, G_MAXULONG, 4096, flags);
}
else if (prop_id == bytesperread_id) {
pspec = g_param_spec_int ("bytesperread", "Bytes per read",
"Number of bytes to read per buffer",
G_MININT, G_MAXINT, 0, flags);
}
else if (prop_id == dump_id) {
pspec = g_param_spec_boolean ("dump", "Dump",
"Dump bytes to stdout",
FALSE, flags);
}
else if (prop_id == filesize_id) {
pspec = g_param_spec_int64 ("filesize", "File Size",
"Size of the file being read",
0, G_MAXINT64, 0, flags);
}
else if (prop_id == mmapsize_id) {
pspec = g_param_spec_ulong ("mmapsize", "mmap() Block Size",
"Size in bytes of mmap()d regions",
0, G_MAXULONG, 4 * 1048576, flags);
}
else if (prop_id == location_id) {
pspec = g_param_spec_string ("location", "File Location",
"Location of the file to read",
NULL, flags);
}
else if (prop_id == offset_id) {
pspec = g_param_spec_int64 ("offset", "File Offset",
"Byte offset of current read pointer",
0, G_MAXINT64, 0, flags);
}
else if (prop_id == silent_id) {
pspec = g_param_spec_boolean ("silent", "Silent", "Don't produce events",
FALSE, flags);
}
else if (prop_id == touch_id) {
pspec = g_param_spec_boolean ("touch", "Touch read data",
"Touch data to force disk read before "
"push ()", TRUE, flags);
}
else {
g_warning ("Unknown - 'standard' property '%s' id %d from klass %s",
prop_name, arg_id, g_type_name (G_OBJECT_CLASS_TYPE (klass)));
pspec = NULL;
}
if (pspec) {
g_object_class_install_property (klass, arg_id, pspec);
}
}
/**
* gst_element_class_install_std_props:
* @klass: the #GstElementClass to add the properties to.
* @first_name: the name of the first property.
* in a NULL terminated
* @...: the id and flags of the first property, followed by
* further 'name', 'id', 'flags' triplets and terminated by NULL.
*
* Adds a list of standardized properties with types to the @klass.
* the id is for the property switch in your get_prop method, and
* the flags determine readability / writeability.
**/
void
gst_element_class_install_std_props (GstElementClass * klass,
const gchar *first_name, ...)
{
const char *name;
va_list args;
g_return_if_fail (GST_IS_ELEMENT_CLASS (klass));
va_start (args, first_name);
name = first_name;
while (name) {
int arg_id = va_arg (args, int);
int flags = va_arg (args, int);
gst_element_populate_std_props ((GObjectClass *) klass, name, arg_id, flags);
name = va_arg (args, char *);
}
va_end (args);
}
/**
* gst_element_get_managing_bin:
* @element: a #GstElement to get the managing bin of.
*
* Gets the managing bin (a pipeline or a thread, for example) of an element.
*
* Returns: the #GstBin, or NULL on failure.
**/
GstBin*
gst_element_get_managing_bin (GstElement *element)
{
GstBin *bin;
g_return_val_if_fail (element != NULL, NULL);
bin = GST_BIN (gst_object_get_parent (GST_OBJECT_CAST (element)));
while (bin && !GST_FLAG_IS_SET (GST_OBJECT_CAST (bin), GST_BIN_FLAG_MANAGER))
bin = GST_BIN (gst_object_get_parent (GST_OBJECT_CAST (bin)));
return bin;
}
Reference in a new issue View git blame Copy permalink