gstreamer/gst/gstpad.c
Wim Taymans fdcf9acd4b Fix pad_get_direction wrt ghostpads.
Original commit message from CVS:
* gst/gstpad.c: (gst_pad_get_direction):
* gst/gstpad.h:
* testsuite/bins/interface.c: (main):
* testsuite/refcounting/bin.c: (add_remove_test1),
(add_remove_test2), (main):
* testsuite/refcounting/element.c: (main):
* testsuite/refcounting/element_pad.c: (main):
* testsuite/refcounting/pad.c: (main):
Fix pad_get_direction wrt ghostpads.
Fix some more testsuites.
2005-03-09 17:30:43 +00:00

3859 lines
101 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstpad.c: Pads for linking elements together
*
* 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.
*/
#include "gst_private.h"
#include "gstpad.h"
#include "gstmarshal.h"
#include "gstutils.h"
#include "gstelement.h"
#include "gstbin.h"
#include "gstscheduler.h"
#include "gstevent.h"
#include "gstinfo.h"
#include "gsterror.h"
#include "gstvalue.h"
GST_DEBUG_CATEGORY_STATIC (debug_dataflow);
#define DEBUG_DATA(obj,data,notice) G_STMT_START{\
if (!data) { \
GST_CAT_DEBUG_OBJECT (debug_dataflow, obj, "NULL data value"); \
} else if (GST_IS_EVENT (data)) { \
GST_CAT_DEBUG_OBJECT (debug_dataflow, obj, "%s event %p (type %d, refcount %d)", notice, data, \
GST_EVENT_TYPE (data), GST_DATA_REFCOUNT_VALUE (data)); \
} else { \
GST_CAT_LOG_OBJECT (debug_dataflow, obj, "%s buffer %p (size %u, refcount %d)", notice, data, \
GST_BUFFER_SIZE (data), GST_BUFFER_REFCOUNT_VALUE (data)); \
} \
}G_STMT_END
#define GST_CAT_DEFAULT GST_CAT_PADS
/* realize and pad and grab the lock of the realized pad. */
#define GST_PAD_REALIZE_AND_LOCK(pad, realpad, lost_ghostpad) \
GST_LOCK (pad); \
realpad = GST_PAD_REALIZE (pad); \
if (G_UNLIKELY (realpad == NULL)) { \
GST_UNLOCK (pad); \
goto lost_ghostpad; \
} \
if (G_UNLIKELY (pad != GST_PAD_CAST (realpad))) { \
GST_LOCK (realpad); \
GST_UNLOCK (pad); \
}
enum
{
TEMPL_PAD_CREATED,
/* FILL ME */
TEMPL_LAST_SIGNAL
};
static GstObject *padtemplate_parent_class = NULL;
static guint gst_pad_template_signals[TEMPL_LAST_SIGNAL] = { 0 };
GType _gst_pad_type = 0;
/***** Start with the base GstPad class *****/
static void gst_pad_class_init (GstPadClass * klass);
static void gst_pad_init (GstPad * pad);
static void gst_pad_dispose (GObject * object);
static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
#ifndef GST_DISABLE_LOADSAVE
static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
#endif
static GstObject *pad_parent_class = NULL;
GType
gst_pad_get_type (void)
{
if (!_gst_pad_type) {
static const GTypeInfo pad_info = {
sizeof (GstPadClass), NULL, NULL,
(GClassInitFunc) gst_pad_class_init, NULL, NULL,
sizeof (GstPad),
0,
(GInstanceInitFunc) gst_pad_init, NULL
};
_gst_pad_type = g_type_register_static (GST_TYPE_OBJECT, "GstPad",
&pad_info, 0);
GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW",
GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads");
}
return _gst_pad_type;
}
static void
gst_pad_class_init (GstPadClass * klass)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass *) klass;
pad_parent_class = g_type_class_ref (GST_TYPE_OBJECT);
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pad_dispose);
}
static void
gst_pad_init (GstPad * pad)
{
/* all structs are initialized to NULL by glib */
}
static void
gst_pad_dispose (GObject * object)
{
GstPad *pad = GST_PAD (object);
gst_pad_set_pad_template (pad, NULL);
/* FIXME, we have links to many other things like caps
* and the peer pad... */
G_OBJECT_CLASS (pad_parent_class)->dispose (object);
}
/***** Then do the Real Pad *****/
/* Pad signals and args */
enum
{
REAL_LINKED,
REAL_UNLINKED,
REAL_REQUEST_LINK,
/* FILL ME */
REAL_LAST_SIGNAL
};
enum
{
REAL_ARG_0,
REAL_ARG_CAPS,
REAL_ARG_ACTIVE
/* FILL ME */
};
static void gst_real_pad_class_init (GstRealPadClass * klass);
static void gst_real_pad_init (GstRealPad * pad);
static void gst_real_pad_dispose (GObject * object);
static void gst_real_pad_finalize (GObject * object);
static void gst_real_pad_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_real_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static GstCaps *gst_real_pad_get_caps_unlocked (GstRealPad * realpad);
GType _gst_real_pad_type = 0;
static GstPad *real_pad_parent_class = NULL;
static guint gst_real_pad_signals[REAL_LAST_SIGNAL] = { 0 };
GType
gst_real_pad_get_type (void)
{
if (!_gst_real_pad_type) {
static const GTypeInfo pad_info = {
sizeof (GstRealPadClass), NULL, NULL,
(GClassInitFunc) gst_real_pad_class_init, NULL, NULL,
sizeof (GstRealPad),
0,
(GInstanceInitFunc) gst_real_pad_init, NULL
};
_gst_real_pad_type = g_type_register_static (GST_TYPE_PAD, "GstRealPad",
&pad_info, 0);
}
return _gst_real_pad_type;
}
static void
gst_real_pad_class_init (GstRealPadClass * klass)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
gobject_class = (GObjectClass *) klass;
gstobject_class = (GstObjectClass *) klass;
real_pad_parent_class = g_type_class_ref (GST_TYPE_PAD);
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_real_pad_dispose);
gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_real_pad_finalize);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_real_pad_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_real_pad_get_property);
gst_real_pad_signals[REAL_LINKED] =
g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstRealPadClass, linked), NULL, NULL,
gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
gst_real_pad_signals[REAL_UNLINKED] =
g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstRealPadClass, unlinked), NULL, NULL,
gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
gst_real_pad_signals[REAL_REQUEST_LINK] =
g_signal_new ("request_link", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRealPadClass, request_link), NULL,
NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
g_object_class_install_property (G_OBJECT_CLASS (klass), REAL_ARG_ACTIVE,
g_param_spec_boolean ("active", "Active", "Whether the pad is active.",
TRUE, G_PARAM_READWRITE));
g_object_class_install_property (G_OBJECT_CLASS (klass), REAL_ARG_CAPS,
g_param_spec_boxed ("caps", "Caps", "The capabilities of the pad",
GST_TYPE_CAPS, G_PARAM_READABLE));
#ifndef GST_DISABLE_LOADSAVE
gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_pad_save_thyself);
#endif
gstobject_class->path_string_separator = ".";
}
static void
gst_real_pad_init (GstRealPad * pad)
{
pad->direction = GST_PAD_UNKNOWN;
pad->peer = NULL;
pad->chainfunc = NULL;
pad->ghostpads = NULL;
pad->caps = NULL;
pad->linkfunc = NULL;
pad->getcapsfunc = NULL;
pad->eventfunc = gst_pad_event_default;
pad->convertfunc = gst_pad_convert_default;
pad->queryfunc = gst_pad_query_default;
pad->intlinkfunc = gst_pad_get_internal_links_default;
pad->eventmaskfunc = gst_pad_get_event_masks_default;
pad->formatsfunc = gst_pad_get_formats_default;
pad->querytypefunc = gst_pad_get_query_types_default;
GST_FLAG_UNSET (pad, GST_PAD_ACTIVE);
pad->preroll_lock = g_mutex_new ();
pad->preroll_cond = g_cond_new ();
pad->stream_rec_lock = g_new (GStaticRecMutex, 1);
g_static_rec_mutex_init (pad->stream_rec_lock);
pad->block_cond = g_cond_new ();
gst_probe_dispatcher_init (&pad->probedisp);
}
static void
gst_real_pad_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
g_return_if_fail (GST_IS_PAD (object));
switch (prop_id) {
case REAL_ARG_ACTIVE:
g_warning ("FIXME: not useful any more!!!");
gst_pad_set_active (GST_PAD (object), g_value_get_boolean (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_real_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
g_return_if_fail (GST_IS_PAD (object));
switch (prop_id) {
case REAL_ARG_ACTIVE:
g_value_set_boolean (value, GST_FLAG_IS_SET (object, GST_PAD_ACTIVE));
break;
case REAL_ARG_CAPS:
g_value_set_boxed (value, GST_PAD_CAPS (GST_REAL_PAD (object)));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* FIXME-0.9: Replace these custom functions with proper inheritance via _init
functions and object properties. update: probably later in the cycle. */
/**
* gst_pad_custom_new:
* @type: the #Gtype of the pad.
* @name: the name of the new pad.
* @direction: the #GstPadDirection of the pad.
*
* Creates a new pad with the given name and type in the given direction.
* If name is NULL, a guaranteed unique name (across all pads)
* will be assigned.
* This function makes a copy of the name so you can safely free the name.
*
* Returns: a new #GstPad, or NULL in case of an error.
*
* MT safe.
*/
GstPad *
gst_pad_custom_new (GType type, const gchar * name, GstPadDirection direction)
{
GstRealPad *pad;
pad = g_object_new (type, NULL);
gst_object_set_name (GST_OBJECT (pad), name);
GST_RPAD_DIRECTION (pad) = direction;
return GST_PAD_CAST (pad);
}
/**
* gst_pad_new:
* @name: the name of the new pad.
* @direction: the #GstPadDirection of the pad.
*
* Creates a new real pad with the given name in the given direction.
* If name is NULL, a guaranteed unique name (across all pads)
* will be assigned.
* This function makes a copy of the name so you can safely free the name.
*
* Returns: a new #GstPad, or NULL in case of an error.
*
* MT safe.
*/
GstPad *
gst_pad_new (const gchar * name, GstPadDirection direction)
{
return gst_pad_custom_new (gst_real_pad_get_type (), name, direction);
}
/**
* gst_pad_custom_new_from_template:
* @type: the custom #GType of the pad.
* @templ: the #GstPadTemplate to instantiate from.
* @name: the name of the new pad.
*
* Creates a new custom pad with the given name from the given template.
* If name is NULL, a guaranteed unique name (across all pads)
* will be assigned.
* This function makes a copy of the name so you can safely free the name.
*
* Returns: a new #GstPad, or NULL in case of an error.
*/
GstPad *
gst_pad_custom_new_from_template (GType type, GstPadTemplate * templ,
const gchar * name)
{
GstPad *pad;
g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
pad = gst_pad_custom_new (type, name, templ->direction);
gst_pad_set_pad_template (pad, templ);
return pad;
}
/**
* gst_pad_new_from_template:
* @templ: the pad template to use
* @name: the name of the element
*
* Creates a new real pad with the given name from the given template.
* If name is NULL, a guaranteed unique name (across all pads)
* will be assigned.
* This function makes a copy of the name so you can safely free the name.
*
* Returns: a new #GstPad, or NULL in case of an error.
*/
GstPad *
gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
{
return gst_pad_custom_new_from_template (gst_real_pad_get_type (),
templ, name);
}
/**
* gst_pad_get_direction:
* @pad: a #GstPad to get the direction of.
*
* Gets the direction of the pad. The direction of the pad is
* decided at construction time so this function does not take
* the LOCK.
*
* Returns: the #GstPadDirection of the pad.
*
* MT safe.
*/
GstPadDirection
gst_pad_get_direction (GstPad * pad)
{
GstPadDirection result;
GstRealPad *realpad;
/* PAD_UNKNOWN is a little silly but we need some sort of
* error return value */
g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
result = GST_RPAD_DIRECTION (realpad);
GST_UNLOCK (realpad);
return result;
/* errors */
lost_ghostpad:
{
return GST_PAD_UNKNOWN;
}
}
/**
* gst_pad_set_active:
* @pad: the #GstPad to activate or deactivate.
* @active: TRUE to activate the pad.
*
* Activates or deactivates the given pad.
*
* Returns: TRUE if the operation was successfull.
*
* MT safe.
*/
gboolean
gst_pad_set_active (GstPad * pad, GstActivateMode mode)
{
GstRealPad *realpad;
gboolean old;
GstPadActivateFunction activatefunc;
gboolean active;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
active = (mode != GST_ACTIVATE_NONE);
old = GST_PAD_IS_ACTIVE (realpad);
/* if nothing changed, we can just exit */
if (G_UNLIKELY (old == active))
goto exit;
/* make sure data is disallowed when going inactive */
if (!active) {
GST_CAT_DEBUG (GST_CAT_PADS, "de-activating pad %s:%s",
GST_DEBUG_PAD_NAME (realpad));
GST_FLAG_UNSET (realpad, GST_PAD_ACTIVE);
/* unlock blocked pads so element can resume and stop */
GST_PAD_BLOCK_SIGNAL (realpad);
}
if (active) {
if (GST_PAD_DIRECTION (pad) == GST_PAD_SRC) {
if (mode == GST_ACTIVATE_PULL) {
if (!realpad->getrangefunc)
goto wrong_mode;
} else {
/* we can push if driven by a chain or loop on the sink pad */
}
} else { /* sink pads */
if (mode == GST_ACTIVATE_PULL) {
/* the src can drive us with getrange */
} else {
if (!realpad->chainfunc)
goto wrong_mode;
}
}
}
activatefunc = realpad->activatefunc;
if (activatefunc) {
gboolean result;
GST_CAT_DEBUG (GST_CAT_PADS,
"calling activate function on pad %s:%s with mode %d",
GST_DEBUG_PAD_NAME (realpad), mode);
/* unlock so element can sync */
GST_UNLOCK (realpad);
result = activatefunc (GST_PAD_CAST (realpad), mode);
/* and lock again */
GST_LOCK (realpad);
if (result == FALSE)
goto activate_error;
}
/* when going to active alow data passing now */
if (active) {
GST_CAT_DEBUG (GST_CAT_PADS, "activating pad %s:%s",
GST_DEBUG_PAD_NAME (realpad));
GST_FLAG_SET (realpad, GST_PAD_ACTIVE);
}
exit:
GST_UNLOCK (realpad);
return TRUE;
/* errors */
lost_ghostpad:
{
return FALSE;
}
wrong_mode:
{
GST_CAT_DEBUG (GST_CAT_PADS,
"pad %s:%s lacks functions to be active in mode %d",
GST_DEBUG_PAD_NAME (realpad), mode);
GST_UNLOCK (realpad);
return FALSE;
}
activate_error:
{
GST_CAT_DEBUG (GST_CAT_PADS,
"activate function returned FALSE for pad %s:%s",
GST_DEBUG_PAD_NAME (realpad));
GST_UNLOCK (realpad);
return FALSE;
}
}
/**
* gst_pad_is_active:
* @pad: the #GstPad to query
*
* Query if a pad is active
*
* Returns: TRUE if the pad is active.
*
* MT safe.
*/
gboolean
gst_pad_is_active (GstPad * pad)
{
gboolean result = FALSE;
GstRealPad *realpad;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
result = GST_FLAG_IS_SET (realpad, GST_PAD_ACTIVE);
GST_UNLOCK (realpad);
return result;
lost_ghostpad:
{
return FALSE;
}
}
/**
* gst_pad_set_blocked_async:
* @pad: the #GstPad to block or unblock
* @blocked: boolean indicating we should block or unblock
* @callback: #GstPadBlockCallback that will be called when the
* operation succeeds.
* @user_data: user data passed to the callback
*
* Blocks or unblocks the dataflow on a pad. The provided callback
* is called when the operation succeeds. This can take a while as
* the pad can only become blocked when real dataflow is happening.
* When the pipeline is stalled, for example in PAUSED, this can
* take an indeterminate amount of time.
* You can pass NULL as the callback to make this call block. Be
* carefull with this blocking call as it might not return for
* reasons stated above.
*
* Returns: TRUE if the pad could be blocked. This function can fail
* if wrong parameters were passed or the pad was already in the
* requested state.
*
* MT safe.
*/
gboolean
gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
GstPadBlockCallback callback, gpointer user_data)
{
gboolean was_blocked;
GstRealPad *realpad;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
was_blocked = GST_RPAD_IS_BLOCKED (realpad);
if (G_UNLIKELY (was_blocked == blocked))
goto had_right_state;
if (blocked) {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, realpad, "blocking pad %s:%s",
GST_DEBUG_PAD_NAME (realpad));
GST_FLAG_SET (realpad, GST_PAD_BLOCKED);
realpad->block_callback = callback;
realpad->block_data = user_data;
if (!callback) {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, realpad, "waiting for block");
GST_PAD_BLOCK_WAIT (realpad);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, realpad, "blocked");
}
} else {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, realpad, "unblocking pad %s:%s",
GST_DEBUG_PAD_NAME (realpad));
GST_FLAG_UNSET (realpad, GST_PAD_BLOCKED);
realpad->block_callback = callback;
realpad->block_data = user_data;
if (callback) {
GST_PAD_BLOCK_SIGNAL (realpad);
} else {
GST_PAD_BLOCK_SIGNAL (realpad);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, realpad, "waiting for unblock");
GST_PAD_BLOCK_WAIT (realpad);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, realpad, "unblocked");
}
}
GST_UNLOCK (realpad);
return TRUE;
lost_ghostpad:
{
return FALSE;
}
had_right_state:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, realpad,
"pad %s:%s was in right state", GST_DEBUG_PAD_NAME (realpad));
GST_UNLOCK (realpad);
return FALSE;
}
}
/**
* gst_pad_set_blocked:
* @pad: the #GstPad to block or unblock
* @blocked: boolean indicating we should block or unblock
*
* Blocks or unblocks the dataflow on a pad. This function is
* a shortcut for @gst_pad_set_blocked_async() with a NULL
* callback.
*
* Returns: TRUE if the pad could be blocked. This function can fail
* wrong parameters were passed or the pad was already in the
* requested state.
*
* MT safe.
*/
gboolean
gst_pad_set_blocked (GstPad * pad, gboolean blocked)
{
return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
}
/**
* gst_pad_is_blocked:
* @pad: the #GstPad to query
*
* Checks if the pad is blocked or not. This function returns the
* last requested state of the pad. It is not certain that the pad
* is actually blocked at this point.
*
* Returns: TRUE if the pad is blocked.
*
* MT safe.
*/
gboolean
gst_pad_is_blocked (GstPad * pad)
{
gboolean result = FALSE;
GstRealPad *realpad;
g_return_val_if_fail (GST_IS_PAD (pad), result);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
result = GST_FLAG_IS_SET (realpad, GST_PAD_BLOCKED);
GST_UNLOCK (realpad);
return result;
lost_ghostpad:
{
return FALSE;
}
}
/**
* gst_pad_set_activate_function:
* @pad: a real sink #GstPad.
* @chain: the #GstPadActivateFunction to set.
*
* Sets the given activate function for the pad. The activate function is called to
* start or stop dataflow on a pad.
*/
void
gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_ACTIVATEFUNC (pad) = activate;
GST_CAT_DEBUG (GST_CAT_PADS, "activatefunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activate));
}
/**
* gst_pad_set_loop_function:
* @pad: a real sink #GstPad.
* @chain: the #GstPadLoopFunction to set.
*
* Sets the given loop function for the pad. The loop function is called
* repeadedly to pull/push buffers from/to the peer pad.
*/
void
gst_pad_set_loop_function (GstPad * pad, GstPadLoopFunction loop)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_LOOPFUNC (pad) = loop;
GST_CAT_DEBUG (GST_CAT_PADS, "loopfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (loop));
}
/**
* gst_pad_set_chain_function:
* @pad: a real sink #GstPad.
* @chain: the #GstPadChainFunction to set.
*
* Sets the given chain function for the pad. The chain function is called to
* process a #GstBuffer input buffer.
*/
void
gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
g_return_if_fail (GST_RPAD_DIRECTION (pad) == GST_PAD_SINK);
GST_RPAD_CHAINFUNC (pad) = chain;
GST_CAT_DEBUG (GST_CAT_PADS, "chainfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (chain));
}
/**
* gst_pad_set_getrange_function:
* @pad: a real source #GstPad.
* @get: the #GstPadGetRangeFunction to set.
*
* Sets the given getrange function for the pad. The getrange function is called to
* produce a new #GstBuffer to start the processing pipeline. Getrange functions cannot
* return %NULL.
*/
void
gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
g_return_if_fail (GST_RPAD_DIRECTION (pad) == GST_PAD_SRC);
GST_RPAD_GETRANGEFUNC (pad) = get;
GST_CAT_DEBUG (GST_CAT_PADS, "getrangefunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (get));
}
/**
* gst_pad_set_event_function:
* @pad: a real source #GstPad.
* @event: the #GstPadEventFunction to set.
*
* Sets the given event handler for the pad.
*/
void
gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_EVENTFUNC (pad) = event;
GST_CAT_DEBUG (GST_CAT_PADS, "eventfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (event));
}
/**
* gst_pad_set_event_mask_function:
* @pad: a real #GstPad of either direction.
* @mask_func: the #GstPadEventMaskFunction to set.
*
* Sets the given event mask function for the pad.
*/
void
gst_pad_set_event_mask_function (GstPad * pad,
GstPadEventMaskFunction mask_func)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_EVENTMASKFUNC (pad) = mask_func;
GST_CAT_DEBUG (GST_CAT_PADS, "eventmaskfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (mask_func));
}
/**
* gst_pad_get_event_masks:
* @pad: a #GstPad.
*
* Gets the array of eventmasks from the given pad.
*
* Returns: a zero-terminated array of #GstEventMask, or NULL if the pad does
* not have an event mask function.
*/
const GstEventMask *
gst_pad_get_event_masks (GstPad * pad)
{
GstRealPad *rpad;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
rpad = GST_PAD_REALIZE (pad);
g_return_val_if_fail (rpad, NULL);
if (GST_RPAD_EVENTMASKFUNC (rpad))
return GST_RPAD_EVENTMASKFUNC (rpad) (GST_PAD (pad));
return NULL;
}
static gboolean
gst_pad_get_event_masks_dispatcher (GstPad * pad, const GstEventMask ** data)
{
*data = gst_pad_get_event_masks (pad);
return TRUE;
}
/**
* gst_pad_get_event_masks_default:
* @pad: a #GstPad.
*
* Invokes the default event masks dispatcher on the pad.
*
* Returns: a zero-terminated array of #GstEventMask, or NULL if none of the
* internally-linked pads have an event mask function.
*/
const GstEventMask *
gst_pad_get_event_masks_default (GstPad * pad)
{
GstEventMask *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
gst_pad_get_event_masks_dispatcher, &result);
return result;
}
/**
* gst_pad_set_convert_function:
* @pad: a real #GstPad of either direction.
* @convert: the #GstPadConvertFunction to set.
*
* Sets the given convert function for the pad.
*/
void
gst_pad_set_convert_function (GstPad * pad, GstPadConvertFunction convert)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_CONVERTFUNC (pad) = convert;
GST_CAT_DEBUG (GST_CAT_PADS, "convertfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (convert));
}
/**
* gst_pad_set_query_function:
* @pad: a real #GstPad of either direction.
* @query: the #GstPadQueryFunction to set.
*
* Set the given query function for the pad.
*/
void
gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_QUERYFUNC (pad) = query;
GST_CAT_DEBUG (GST_CAT_PADS, "queryfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (query));
}
/**
* gst_pad_set_query_type_function:
* @pad: a real #GstPad of either direction.
* @type_func: the #GstPadQueryTypeFunction to set.
*
* Set the given query type function for the pad.
*/
void
gst_pad_set_query_type_function (GstPad * pad,
GstPadQueryTypeFunction type_func)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_QUERYTYPEFUNC (pad) = type_func;
GST_CAT_DEBUG (GST_CAT_PADS, "querytypefunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (type_func));
}
/**
* gst_pad_get_query_types:
* @pad: a #GstPad.
*
* Get an array of supported queries that can be performed
* on this pad.
*
* Returns: a zero-terminated array of #GstQueryType.
*/
const GstQueryType *
gst_pad_get_query_types (GstPad * pad)
{
GstRealPad *rpad;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
rpad = GST_PAD_REALIZE (pad);
g_return_val_if_fail (rpad, NULL);
if (GST_RPAD_QUERYTYPEFUNC (rpad))
return GST_RPAD_QUERYTYPEFUNC (rpad) (GST_PAD (pad));
return NULL;
}
static gboolean
gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
{
*data = gst_pad_get_query_types (pad);
return TRUE;
}
/**
* gst_pad_get_query_types_default:
* @pad: a #GstPad.
*
* Invoke the default dispatcher for the query types on
* the pad.
*
* Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
* internally-linked pads has a query types function.
*/
const GstQueryType *
gst_pad_get_query_types_default (GstPad * pad)
{
GstQueryType *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
gst_pad_get_query_types_dispatcher, &result);
return result;
}
/**
* gst_pad_set_internal_link_function:
* @pad: a real #GstPad of either direction.
* @intlink: the #GstPadIntLinkFunction to set.
*
* Sets the given internal link function for the pad.
*/
void
gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_INTLINKFUNC (pad) = intlink;
GST_CAT_DEBUG (GST_CAT_PADS, "internal link for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (intlink));
}
/**
* gst_pad_set_formats_function:
* @pad: a real #GstPad of either direction.
* @formats: the #GstPadFormatsFunction to set.
*
* Sets the given formats function for the pad.
*/
void
gst_pad_set_formats_function (GstPad * pad, GstPadFormatsFunction formats)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_FORMATSFUNC (pad) = formats;
GST_CAT_DEBUG (GST_CAT_PADS, "formats function for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (formats));
}
/**
* gst_pad_set_link_function:
* @pad: a real #GstPad.
* @link: the #GstPadLinkFunction to set.
*
* Sets the given link function for the pad. It will be called when the pad is
* linked or relinked with caps. The caps passed to the link function is
* the filtered caps for the connnection. It can contain a non fixed caps.
*
* The return value GST_PAD_LINK_OK should be used when the connection can be
* made.
*
* The return value GST_PAD_LINK_REFUSED should be used when the connection
* cannot be made for some reason.
*/
void
gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_LINKFUNC (pad) = link;
GST_CAT_DEBUG (GST_CAT_PADS, "linkfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (link));
}
/**
* gst_pad_set_unlink_function:
* @pad: a real #GstPad.
* @unlink: the #GstPadUnlinkFunction to set.
*
* Sets the given unlink function for the pad. It will be called
* when the pad is unlinked.
*/
void
gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_UNLINKFUNC (pad) = unlink;
GST_CAT_DEBUG (GST_CAT_PADS, "unlinkfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (unlink));
}
/**
* gst_pad_set_getcaps_function:
* @pad: a real #GstPad.
* @getcaps: the #GstPadGetCapsFunction to set.
*
* Sets the given getcaps function for the pad. @getcaps should return the
* allowable caps for a pad in the context of the element's state, its link to
* other elements, and the devices or files it has opened. These caps must be a
* subset of the pad template caps. In the NULL state with no links, @getcaps
* should ideally return the same caps as the pad template. In rare
* circumstances, an object property can affect the caps returned by @getcaps,
* but this is discouraged.
*
* You do not need to call this function if @pad's allowed caps are always the
* same as the pad template caps. This can only be true if the padtemplate
* has fixed simple caps.
*
* For most filters, the caps returned by @getcaps is directly affected by the
* allowed caps on other pads. For demuxers and decoders, the caps returned by
* the srcpad's getcaps function is directly related to the stream data. Again,
* @getcaps should return the most specific caps it reasonably can, since this
* helps with autoplugging.
*
* Note that the return value from @getcaps is owned by the caller, so the caller
* should unref the caps after usage.
*/
void
gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_GETCAPSFUNC (pad) = getcaps;
GST_CAT_DEBUG (GST_CAT_PADS, "getcapsfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (getcaps));
}
/**
* gst_pad_set_acceptcaps_function:
* @pad: a real #GstPad.
* @acceptcaps: the #GstPadAcceptCapsFunction to set.
*
* Sets the given acceptcaps function for the pad. The acceptcaps function
* will be called to check if the pad can accept the given caps.
*/
void
gst_pad_set_acceptcaps_function (GstPad * pad,
GstPadAcceptCapsFunction acceptcaps)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
GST_CAT_DEBUG (GST_CAT_PADS, "acceptcapsfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (acceptcaps));
}
/**
* gst_pad_set_fixatecaps_function:
* @pad: a real #GstPad.
* @fixatecaps: the #GstPadFixateCapsFunction to set.
*
* Sets the given fixatecaps function for the pad. The fixatecaps function
* will be called whenever the default values for a GstCaps needs to be
* filled in.
*/
void
gst_pad_set_fixatecaps_function (GstPad * pad,
GstPadFixateCapsFunction fixatecaps)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_FIXATECAPSFUNC (pad) = fixatecaps;
GST_CAT_DEBUG (GST_CAT_PADS, "fixatecapsfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (fixatecaps));
}
/**
* gst_pad_set_setcaps_function:
* @pad: a real #GstPad.
* @setcaps: the #GstPadSetCapsFunction to set.
*
* Sets the given setcaps function for the pad. The setcaps function
* will be called whenever a buffer with a new media type is pushed or
* pulled from the pad. The pad/element needs to update it's internal
* structures to process the new media type. If this new type is not
* acceptable, the setcaps function should return FALSE.
*/
void
gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
GST_RPAD_SETCAPSFUNC (pad) = setcaps;
GST_CAT_DEBUG (GST_CAT_PADS, "setcapsfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (setcaps));
}
/**
* gst_pad_set_bufferalloc_function:
* @pad: a real sink #GstPad.
* @bufalloc: the #GstPadBufferAllocFunction to set.
*
* Sets the given bufferalloc function for the pad. Note that the
* bufferalloc function can only be set on sinkpads.
*/
void
gst_pad_set_bufferalloc_function (GstPad * pad,
GstPadBufferAllocFunction bufalloc)
{
g_return_if_fail (GST_IS_REAL_PAD (pad));
g_return_if_fail (GST_PAD_IS_SINK (pad));
GST_RPAD_BUFFERALLOCFUNC (pad) = bufalloc;
GST_CAT_DEBUG (GST_CAT_PADS, "bufferallocfunc for %s:%s set to %s",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (bufalloc));
}
/**
* gst_pad_unlink:
* @srcpad: the source #GstPad to unlink.
* @sinkpad: the sink #GstPad to unlink.
*
* Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
* both pads.
*
* Returns: TRUE if the pads were unlinked. This function returns FALSE if
* the pads were not linked together.
*
* MT safe.
*/
gboolean
gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
{
GstRealPad *realsrc, *realsink;
g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
GST_DEBUG_PAD_NAME (srcpad), srcpad,
GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
GST_PAD_REALIZE_AND_LOCK (srcpad, realsrc, lost_src_ghostpad);
if (G_UNLIKELY (GST_RPAD_DIRECTION (realsrc) != GST_PAD_SRC))
goto not_srcpad;
GST_PAD_REALIZE_AND_LOCK (sinkpad, realsink, lost_sink_ghostpad);
if (G_UNLIKELY (GST_RPAD_DIRECTION (realsink) != GST_PAD_SINK))
goto not_sinkpad;
if (G_UNLIKELY (GST_RPAD_PEER (realsrc) != realsink))
goto not_linked_together;
if (GST_RPAD_UNLINKFUNC (realsrc)) {
GST_RPAD_UNLINKFUNC (realsrc) (GST_PAD (realsrc));
}
if (GST_RPAD_UNLINKFUNC (realsink)) {
GST_RPAD_UNLINKFUNC (realsink) (GST_PAD (realsink));
}
/* first clear peers */
GST_RPAD_PEER (realsrc) = NULL;
GST_RPAD_PEER (realsink) = NULL;
/* clear filter, note that we leave the pad caps as they are */
gst_caps_replace (&GST_RPAD_APPFILTER (realsrc), NULL);
gst_caps_replace (&GST_RPAD_APPFILTER (realsink), NULL);
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
/* fire off a signal to each of the pads telling them
* that they've been unlinked */
g_signal_emit (G_OBJECT (realsrc), gst_real_pad_signals[REAL_UNLINKED],
0, realsink);
g_signal_emit (G_OBJECT (realsink), gst_real_pad_signals[REAL_UNLINKED],
0, realsrc);
GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (realsrc), GST_DEBUG_PAD_NAME (realsink));
return TRUE;
lost_src_ghostpad:
{
return FALSE;
}
not_srcpad:
{
g_critical ("pad %s is not a source pad", GST_PAD_NAME (realsrc));
GST_UNLOCK (realsrc);
return FALSE;
}
lost_sink_ghostpad:
{
GST_UNLOCK (realsrc);
return FALSE;
}
not_sinkpad:
{
g_critical ("pad %s is not a sink pad", GST_PAD_NAME (realsink));
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
return FALSE;
}
not_linked_together:
{
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
return FALSE;
}
}
/**
* gst_pad_is_linked:
* @pad: pad to check
*
* Checks if a @pad is linked to another pad or not.
*
* Returns: TRUE if the pad is linked, FALSE otherwise.
*
* MT safe.
*/
gboolean
gst_pad_is_linked (GstPad * pad)
{
gboolean result;
GstRealPad *realpad;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
result = (GST_PAD_PEER (realpad) != NULL);
GST_UNLOCK (realpad);
return result;
lost_ghostpad:
{
return FALSE;
}
}
/* FIXME leftover from an attempt at refactoring... */
static GstPadLinkReturn
gst_pad_link_prepare_filtered (GstPad * srcpad, GstPad * sinkpad,
GstRealPad ** outrealsrc, GstRealPad ** outrealsink,
const GstCaps * filtercaps)
{
GstRealPad *realsrc, *realsink;
/* generic checks */
g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
/* now we need to deal with the real/ghost stuff */
GST_PAD_REALIZE_AND_LOCK (srcpad, realsrc, lost_src_ghostpad);
if (G_UNLIKELY (GST_RPAD_DIRECTION (realsrc) != GST_PAD_SRC))
goto not_srcpad;
if (G_UNLIKELY (GST_RPAD_PEER (realsrc) != NULL))
goto src_was_linked;
GST_PAD_REALIZE_AND_LOCK (sinkpad, realsink, lost_sink_ghostpad);
if (G_UNLIKELY (GST_RPAD_DIRECTION (realsink) != GST_PAD_SINK))
goto not_sinkpad;
if (G_UNLIKELY (GST_RPAD_PEER (realsink) != NULL))
goto sink_was_linked;
if ((GST_PAD (realsrc) != srcpad) || (GST_PAD (realsink) != sinkpad)) {
GST_CAT_INFO (GST_CAT_PADS, "*actually* linking %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (realsrc), GST_DEBUG_PAD_NAME (realsink));
}
*outrealsrc = realsrc;
*outrealsink = realsink;
/* check pad caps for non-empty intersection */
{
GstCaps *srccaps;
GstCaps *sinkcaps;
srccaps = gst_real_pad_get_caps_unlocked (realsrc);
sinkcaps = gst_real_pad_get_caps_unlocked (realsink);
GST_CAT_DEBUG (GST_CAT_CAPS, "got caps %p and %p", srccaps, sinkcaps);
if (srccaps && sinkcaps) {
GstCaps *caps;
caps = gst_caps_intersect (srccaps, sinkcaps);
GST_CAT_DEBUG (GST_CAT_CAPS,
"intersection caps %p %" GST_PTR_FORMAT, caps, caps);
if (filtercaps) {
GstCaps *tmp;
tmp = gst_caps_intersect (caps, filtercaps);
gst_caps_unref (caps);
caps = tmp;
}
if (!caps || gst_caps_is_empty (caps))
goto no_format;
}
}
/* FIXME check pad scheduling for non-empty intersection */
/* update filter */
if (filtercaps) {
GstCaps *filtercopy;
filtercopy = gst_caps_copy (filtercaps);
filtercopy = gst_caps_ref (filtercopy);
gst_caps_replace (&GST_PAD_APPFILTER (realsrc), filtercopy);
gst_caps_replace (&GST_PAD_APPFILTER (realsink), filtercopy);
} else {
gst_caps_replace (&GST_PAD_APPFILTER (realsrc), NULL);
gst_caps_replace (&GST_PAD_APPFILTER (realsink), NULL);
}
return GST_PAD_LINK_OK;
lost_src_ghostpad:
{
return GST_PAD_LINK_REFUSED;
}
not_srcpad:
{
g_critical ("pad %s is not a source pad", GST_PAD_NAME (realsrc));
GST_UNLOCK (realsrc);
return GST_PAD_LINK_WRONG_DIRECTION;
}
src_was_linked:
{
GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was linked",
GST_DEBUG_PAD_NAME (realsrc));
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_UNLOCK (realsrc);
return GST_PAD_LINK_WAS_LINKED;
}
lost_sink_ghostpad:
{
GST_DEBUG ("lost sink ghostpad");
GST_UNLOCK (realsrc);
return GST_PAD_LINK_REFUSED;
}
not_sinkpad:
{
g_critical ("pad %s is not a sink pad", GST_PAD_NAME (realsink));
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
return GST_PAD_LINK_WRONG_DIRECTION;
}
sink_was_linked:
{
GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was linked",
GST_DEBUG_PAD_NAME (realsink));
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
return GST_PAD_LINK_WAS_LINKED;
}
no_format:
{
GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
return GST_PAD_LINK_NOFORMAT;
}
}
/**
* gst_pad_link_filtered:
* @srcpad: the source #GstPad to link.
* @sinkpad: the sink #GstPad to link.
* @filtercaps: the filter #GstCaps.
*
* Links the source pad and the sink pad, constrained
* by the given filter caps.
*
* The filtercaps will be copied and refcounted, so you should unref
* it yourself after using this function.
*
* Returns: A result code indicating if the connection worked or
* what went wrong.
*
* MT Safe.
*/
GstPadLinkReturn
gst_pad_link_filtered (GstPad * srcpad, GstPad * sinkpad,
const GstCaps * filtercaps)
{
GstRealPad *realsrc, *realsink;
GstPadLinkReturn result;
result = gst_pad_link_prepare_filtered (srcpad, sinkpad, &realsrc, &realsink,
filtercaps);
if (result != GST_PAD_LINK_OK)
goto prepare_failed;
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
/* FIXME released the locks here, concurrent thread might link
* something else. */
if (GST_RPAD_LINKFUNC (realsrc)) {
/* this one will call the peer link function */
result =
GST_RPAD_LINKFUNC (realsrc) (GST_PAD (realsrc), GST_PAD (realsink));
} else if (GST_RPAD_LINKFUNC (realsink)) {
/* if no source link function, we need to call the sink link
* function ourselves. */
result =
GST_RPAD_LINKFUNC (realsink) (GST_PAD (realsink), GST_PAD (realsrc));
} else {
result = GST_PAD_LINK_OK;
}
GST_LOCK (realsrc);
GST_LOCK (realsink);
if (result == GST_PAD_LINK_OK) {
GST_RPAD_PEER (realsrc) = GST_REAL_PAD (realsink);
GST_RPAD_PEER (realsink) = GST_REAL_PAD (realsrc);
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
/* fire off a signal to each of the pads telling them
* that they've been linked */
g_signal_emit (G_OBJECT (realsrc), gst_real_pad_signals[REAL_LINKED],
0, realsink);
g_signal_emit (G_OBJECT (realsink), gst_real_pad_signals[REAL_LINKED],
0, realsrc);
GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
GST_DEBUG_PAD_NAME (realsrc), GST_DEBUG_PAD_NAME (realsink));
} else {
GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
GST_DEBUG_PAD_NAME (realsrc), GST_DEBUG_PAD_NAME (realsink));
/* remove the filter again */
if (filtercaps) {
gst_caps_replace (&GST_RPAD_APPFILTER (realsrc), NULL);
gst_caps_replace (&GST_RPAD_APPFILTER (realsink), NULL);
}
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
}
return result;
prepare_failed:
{
return result;
}
}
/**
* gst_pad_link:
* @srcpad: the source #GstPad to link.
* @sinkpad: the sink #GstPad to link.
*
* Links the source pad to the sink pad.
*
* Returns: A result code indicating if the connection worked or
* what went wrong.
*/
GstPadLinkReturn
gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
{
return gst_pad_link_filtered (srcpad, sinkpad, NULL);
}
static void
gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
{
/* this function would need checks if it weren't static */
GST_LOCK (pad);
gst_object_replace ((GstObject **) & pad->padtemplate, (GstObject *) templ);
GST_UNLOCK (pad);
if (templ) {
gst_object_sink (GST_OBJECT (templ));
g_signal_emit (G_OBJECT (templ),
gst_pad_template_signals[TEMPL_PAD_CREATED], 0, pad);
}
}
/**
* gst_pad_get_pad_template:
* @pad: a #GstPad.
*
* Gets the template for @pad.
*
* Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
* if this pad has no template.
*/
GstPadTemplate *
gst_pad_get_pad_template (GstPad * pad)
{
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
return GST_PAD_PAD_TEMPLATE (pad);
}
/**
* gst_pad_get_real_parent:
* @pad: a #GstPad to get the real parent of.
*
* Gets the real parent object of this pad. If the pad
* is a ghost pad, the actual owner of the real pad is
* returned, as opposed to #gst_pad_get_parent().
* Unref the object after use.
*
* Returns: the parent #GstElement.
*
* MT safe.
*/
GstElement *
gst_pad_get_real_parent (GstPad * pad)
{
GstRealPad *realpad;
GstElement *element;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
element = GST_PAD_PARENT (realpad);
if (element)
gst_object_ref (GST_OBJECT (element));
GST_UNLOCK (realpad);
return element;
lost_ghostpad:
{
return NULL;
}
}
/* FIXME not MT safe */
static void
gst_pad_add_ghost_pad (GstPad * pad, GstPad * ghostpad)
{
GstRealPad *realpad;
/* if we're ghosting a ghost pad, drill down to find the real pad */
realpad = (GstRealPad *) pad;
while (GST_IS_GHOST_PAD (realpad))
realpad = GST_GPAD_REALPAD (realpad);
g_return_if_fail (GST_IS_REAL_PAD (realpad));
/* will ref the pad template */
GST_GPAD_REALPAD (ghostpad) = realpad;
realpad->ghostpads = g_list_prepend (realpad->ghostpads, ghostpad);
gst_pad_set_pad_template (GST_PAD (ghostpad), GST_PAD_PAD_TEMPLATE (pad));
}
static void
gst_pad_remove_ghost_pad (GstPad * pad, GstPad * ghostpad)
{
GstRealPad *realpad;
realpad = GST_PAD_REALIZE (pad);
g_return_if_fail (GST_GPAD_REALPAD (ghostpad) == realpad);
gst_pad_set_pad_template (GST_PAD (ghostpad), NULL);
realpad->ghostpads = g_list_remove (realpad->ghostpads, ghostpad);
GST_GPAD_REALPAD (ghostpad) = NULL;
}
/**
* gst_pad_relink_filtered:
* @srcpad: the source #GstPad to relink.
* @sinkpad: the sink #GstPad to relink.
* @filtercaps: the #GstPad to use as a filter in the relink.
*
* Relinks the given source and sink pad, constrained by the given
* capabilities. If the relink fails, the pads are unlinked
* and an error code is returned.
*
* Returns: The result code of the operation.
*
* MT safe
*/
GstPadLinkReturn
gst_pad_relink_filtered (GstPad * srcpad, GstPad * sinkpad,
const GstCaps * filtercaps)
{
GstRealPad *realsrc, *realsink;
/* FIXME refactor and share code with link/unlink */
/* generic checks */
g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
GST_CAT_INFO (GST_CAT_PADS, "trying to relink %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
/* now we need to deal with the real/ghost stuff */
GST_PAD_REALIZE_AND_LOCK (srcpad, realsrc, lost_src_ghostpad);
if (G_UNLIKELY (GST_RPAD_DIRECTION (realsrc) != GST_PAD_SRC))
goto not_srcpad;
GST_PAD_REALIZE_AND_LOCK (sinkpad, realsink, lost_sink_ghostpad);
if (G_UNLIKELY (GST_RPAD_DIRECTION (realsink) != GST_PAD_SINK))
goto not_sinkpad;
if (G_UNLIKELY (GST_RPAD_PEER (realsink) != realsrc))
goto not_linked_together;
if ((GST_PAD (realsrc) != srcpad) || (GST_PAD (realsink) != sinkpad)) {
GST_CAT_INFO (GST_CAT_PADS, "*actually* relinking %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (realsrc), GST_DEBUG_PAD_NAME (realsink));
}
/* update filter */
if (filtercaps) {
GstCaps *filtercopy;
filtercopy = gst_caps_copy (filtercaps);
filtercopy = gst_caps_ref (filtercopy);
gst_caps_replace (&GST_PAD_APPFILTER (realsrc), filtercopy);
gst_caps_replace (&GST_PAD_APPFILTER (realsink), filtercopy);
} else {
gst_caps_replace (&GST_PAD_APPFILTER (realsrc), NULL);
gst_caps_replace (&GST_PAD_APPFILTER (realsink), NULL);
}
/* clear caps to force renegotiation */
gst_caps_replace (&GST_PAD_CAPS (realsrc), NULL);
gst_caps_replace (&GST_PAD_CAPS (realsink), NULL);
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
GST_CAT_INFO (GST_CAT_PADS, "relinked %s:%s and %s:%s, successful",
GST_DEBUG_PAD_NAME (realsrc), GST_DEBUG_PAD_NAME (realsink));
return GST_PAD_LINK_OK;
lost_src_ghostpad:
{
return GST_PAD_LINK_REFUSED;
}
not_srcpad:
{
g_critical ("pad %s is not a source pad", GST_PAD_NAME (realsrc));
GST_UNLOCK (realsrc);
return GST_PAD_LINK_WRONG_DIRECTION;
}
lost_sink_ghostpad:
{
GST_DEBUG ("lost sink ghostpad");
GST_UNLOCK (realsrc);
return GST_PAD_LINK_REFUSED;
}
not_sinkpad:
{
g_critical ("pad %s is not a sink pad", GST_PAD_NAME (realsink));
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
return GST_PAD_LINK_WRONG_DIRECTION;
}
not_linked_together:
{
GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was not linked with sink %s:%s",
GST_DEBUG_PAD_NAME (realsrc), GST_DEBUG_PAD_NAME (realsink));
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_UNLOCK (realsink);
GST_UNLOCK (realsrc);
return GST_PAD_LINK_REFUSED;
}
}
/* should be called with the pad LOCK held */
static GstCaps *
gst_real_pad_get_caps_unlocked (GstRealPad * realpad)
{
GstCaps *result = NULL, *filter;
GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
GST_DEBUG_PAD_NAME (realpad), realpad);
if (GST_RPAD_GETCAPSFUNC (realpad)) {
GST_CAT_DEBUG (GST_CAT_CAPS, "dispatching to pad getcaps function");
GST_FLAG_SET (realpad, GST_PAD_IN_GETCAPS);
GST_UNLOCK (realpad);
result = GST_RPAD_GETCAPSFUNC (realpad) (GST_PAD (realpad));
GST_LOCK (realpad);
GST_FLAG_UNSET (realpad, GST_PAD_IN_GETCAPS);
if (result == NULL) {
g_critical ("pad %s:%s returned NULL caps from getcaps function\n",
GST_DEBUG_PAD_NAME (realpad));
} else {
#ifndef G_DISABLE_ASSERT
/* check that the returned caps are a real subset of the template caps */
if (GST_PAD_PAD_TEMPLATE (realpad)) {
const GstCaps *templ_caps =
GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (realpad));
if (!gst_caps_is_subset (result, templ_caps)) {
GstCaps *temp;
GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, realpad,
"pad returned caps %" GST_PTR_FORMAT
" which are not a real subset of its template caps %"
GST_PTR_FORMAT, result, templ_caps);
g_warning
("pad %s:%s returned caps that are not a real subset of its template caps",
GST_DEBUG_PAD_NAME (realpad));
temp = gst_caps_intersect (templ_caps, result);
gst_caps_unref (result);
result = temp;
}
}
#endif
goto done;
}
}
if (GST_PAD_PAD_TEMPLATE (realpad)) {
GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (realpad);
result = GST_PAD_TEMPLATE_CAPS (templ);
GST_CAT_DEBUG (GST_CAT_CAPS,
"using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
result);
result = gst_caps_ref (result);
goto done;
}
if (GST_RPAD_CAPS (realpad)) {
result = GST_RPAD_CAPS (realpad);
GST_CAT_DEBUG (GST_CAT_CAPS,
"using pad caps %p %" GST_PTR_FORMAT, result, result);
result = gst_caps_ref (result);
goto done;
}
GST_CAT_DEBUG (GST_CAT_CAPS, "pad has no caps");
result = gst_caps_new_empty ();
done:
filter = GST_RPAD_APPFILTER (realpad);
if (filter) {
GstCaps *temp = result;
GST_CAT_DEBUG (GST_CAT_CAPS,
"app filter %p %" GST_PTR_FORMAT, filter, filter);
result = gst_caps_intersect (temp, filter);
gst_caps_unref (temp);
GST_CAT_DEBUG (GST_CAT_CAPS,
"caps after intersection with app filter %p %" GST_PTR_FORMAT, result,
result);
}
return result;
}
/**
* gst_pad_get_caps:
* @pad: a #GstPad to get the capabilities of.
*
* Gets the capabilities of this pad.
*
* Returns: the #GstCaps of this pad. This function returns a new caps, so use
* gst_caps_unref to get rid of it.
*
* MT safe.
*/
GstCaps *
gst_pad_get_caps (GstPad * pad)
{
GstRealPad *realpad;
GstCaps *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
/* now we need to deal with the real/ghost stuff */
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
GST_DEBUG_PAD_NAME (realpad), realpad);
if (G_UNLIKELY (GST_RPAD_IS_IN_GETCAPS (realpad)))
goto was_dispatching;
result = gst_real_pad_get_caps_unlocked (realpad);
GST_UNLOCK (realpad);
return result;
lost_ghostpad:
{
return NULL;
}
was_dispatching:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"pad %s:%s is already dispatching!", GST_DEBUG_PAD_NAME (realpad));
g_warning ("pad %s:%s recursively called getcaps!",
GST_DEBUG_PAD_NAME (realpad));
GST_UNLOCK (realpad);
return NULL;
}
}
/**
* gst_pad_peer_get_caps:
* @pad: a #GstPad to get the peer capabilities of.
*
* Gets the capabilities of the peer connected to this pad.
*
* Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
* gst_caps_unref to get rid of it.
*/
GstCaps *
gst_pad_peer_get_caps (GstPad * pad)
{
GstRealPad *realpad, *peerpad;
GstCaps *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
/* now we need to deal with the real/ghost stuff */
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
GST_CAT_DEBUG (GST_CAT_CAPS, "get peer caps of %s:%s (%p)",
GST_DEBUG_PAD_NAME (realpad), realpad);
peerpad = GST_RPAD_PEER (realpad);
if (G_UNLIKELY (peerpad == NULL))
goto no_peer;
if (G_UNLIKELY (GST_RPAD_IS_IN_GETCAPS (peerpad)))
goto was_dispatching;
gst_object_ref (GST_OBJECT (peerpad));
GST_UNLOCK (realpad);
result = gst_pad_get_caps (GST_PAD_CAST (peerpad));
gst_object_unref (GST_OBJECT (peerpad));
return result;
lost_ghostpad:
{
return NULL;
}
no_peer:
{
GST_UNLOCK (realpad);
return gst_caps_new_any ();
}
was_dispatching:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"pad %s:%s is already dispatching!", GST_DEBUG_PAD_NAME (realpad));
g_warning ("pad %s:%s recursively called getcaps!",
GST_DEBUG_PAD_NAME (realpad));
GST_UNLOCK (realpad);
return NULL;
}
}
/**
* gst_pad_fixate_caps:
* @pad: a #GstPad to fixate
*
* Fixate a caps on the given pad.
*
* Returns: a fixated #GstCaps.
*/
GstCaps *
gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
{
/* FIXME, implement me, call the fixate function for the pad */
return caps;
}
/**
* gst_pad_accept_caps:
* @pad: a #GstPad to check
*
* Check if the given pad accepts the caps.
*
* Returns: TRUE if the pad can accept the caps.
*/
gboolean
gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
{
GstRealPad *realpad;
gboolean result;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
/* now we need to deal with the real/ghost stuff */
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
GST_CAT_DEBUG (GST_CAT_CAPS, "pad accept caps of %s:%s (%p)",
GST_DEBUG_PAD_NAME (realpad), realpad);
/* FIXME, call accept function */
result = FALSE;
GST_UNLOCK (realpad);
return result;
lost_ghostpad:
{
return FALSE;
}
}
/**
* gst_pad_peer_accept_caps:
* @pad: a #GstPad to check
*
* Check if the given pad accepts the caps.
*
* Returns: TRUE if the pad can accept the caps.
*/
gboolean
gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
{
GstRealPad *realpad, *peerpad;
gboolean result;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
/* now we need to deal with the real/ghost stuff */
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
GST_CAT_DEBUG (GST_CAT_CAPS, "peer accept caps of %s:%s (%p)",
GST_DEBUG_PAD_NAME (realpad), realpad);
peerpad = GST_RPAD_PEER (realpad);
if (G_UNLIKELY (peerpad == NULL))
goto no_peer;
result = gst_pad_accept_caps (GST_PAD_CAST (peerpad), caps);
GST_UNLOCK (realpad);
return result;
lost_ghostpad:
{
return FALSE;
}
no_peer:
{
GST_UNLOCK (realpad);
return TRUE;
}
}
/**
* gst_pad_set_caps:
* @pad: a #GstPad to set the capabilities of.
* @caps: a #GstCaps to set.
*
* Sets the capabilities of this pad. The caps must be fixed. Any previous
* caps on the pad will be unreffed. This function refs the caps so you should
* unref if as soon as you don't need it anymore.
* It is possible to set NULL caps, which will make the pad unnegotiated
* again.
*
* Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
* or bad parameters were provided to this function.
*
* MT safe.
*/
gboolean
gst_pad_set_caps (GstPad * pad, GstCaps * caps)
{
GstPadSetCapsFunction setcaps;
g_return_val_if_fail (GST_IS_REAL_PAD (pad), FALSE);
GST_LOCK (pad);
setcaps = GST_RPAD_SETCAPSFUNC (pad);
/* call setcaps function to configure the pad */
if (setcaps != NULL) {
if (!GST_RPAD_IS_IN_SETCAPS (pad)) {
GST_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
GST_UNLOCK (pad);
if (!setcaps (pad, caps))
goto could_not_set;
GST_LOCK (pad);
} else {
GST_CAT_DEBUG (GST_CAT_CAPS, "pad %s:%s was dispatching",
GST_DEBUG_PAD_NAME (pad));
}
}
if (GST_PAD_CAPS (pad))
gst_caps_unref (GST_PAD_CAPS (pad));
if (caps)
caps = gst_caps_ref (caps);
GST_PAD_CAPS (pad) = caps;
GST_CAT_DEBUG (GST_CAT_CAPS, "%s:%s caps %" GST_PTR_FORMAT,
GST_DEBUG_PAD_NAME (pad), caps);
GST_UNLOCK (pad);
g_object_notify (G_OBJECT (pad), "caps");
return TRUE;
could_not_set:
{
GST_LOCK (pad);
GST_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
GST_UNLOCK (pad);
GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " could not be set",
caps);
return FALSE;
}
}
static gboolean
gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
{
GstPadAcceptCapsFunction acceptcaps;
GstPadSetCapsFunction setcaps;
acceptcaps = GST_RPAD_ACCEPTCAPSFUNC (pad);
setcaps = GST_RPAD_SETCAPSFUNC (pad);
/* See if pad accepts the caps, by calling acceptcaps, only
* needed if no setcaps function */
if (setcaps == NULL && acceptcaps != NULL) {
if (!acceptcaps (pad, caps))
goto not_accepted;
}
/* set caps on pad if call succeeds */
gst_pad_set_caps (pad, caps);
/* no need to unref the caps here, set_caps takes a ref and
* our ref goes away when we leave this function. */
return TRUE;
not_accepted:
{
GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
return FALSE;
}
}
static gboolean
gst_pad_configure_src (GstPad * pad, GstCaps * caps)
{
GstPadAcceptCapsFunction acceptcaps;
GstPadSetCapsFunction setcaps;
acceptcaps = GST_RPAD_ACCEPTCAPSFUNC (pad);
setcaps = GST_RPAD_SETCAPSFUNC (pad);
/* See if pad accepts the caps, by calling acceptcaps, only
* needed if no setcaps function */
if (setcaps == NULL && acceptcaps != NULL) {
if (!acceptcaps (pad, caps))
goto not_accepted;
}
/* set caps on pad if call succeeds */
gst_pad_set_caps (pad, caps);
/* no need to unref the caps here, set_caps takes a ref and
* our ref goes away when we leave this function. */
return TRUE;
not_accepted:
{
GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
return FALSE;
}
}
/**
* gst_pad_get_pad_template_caps:
* @pad: a #GstPad to get the template capabilities from.
*
* Gets the capabilities for @pad's template.
*
* Returns: the #GstCaps of this pad template. If you intend to keep a reference
* on the caps, make a copy (see gst_caps_copy ()).
*/
const GstCaps *
gst_pad_get_pad_template_caps (GstPad * pad)
{
static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
if (GST_PAD_PAD_TEMPLATE (pad))
return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
return gst_static_caps_get (&anycaps);
}
/**
* gst_pad_get_peer:
* @pad: a #GstPad to get the peer of.
*
* Gets the peer of @pad. This function refs the peer pad so
* you need to unref it after use.
*
* Returns: the peer #GstPad. Unref after usage.
*
* MT safe.
*/
GstPad *
gst_pad_get_peer (GstPad * pad)
{
GstRealPad *realpad;
GstRealPad *result;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
result = GST_RPAD_PEER (realpad);
if (result)
gst_object_ref (GST_OBJECT (result));
GST_UNLOCK (realpad);
return GST_PAD_CAST (result);
lost_ghostpad:
{
return NULL;
}
}
/**
* gst_pad_realize:
* @pad: a #GstPad to realize
*
* If the pad is a #GstRealPad, it is simply returned, else
* the #GstGhostPad will be dereffed to the real pad.
*
* After this function you always receive the real pad of
* the provided pad.
*
* This function unrefs the input pad and refs the result so
* that you can write constructs like:
*
* pad = gst_pad_realize(pad)
*
* without having to unref the old pad.
*
* Returns: the real #GstPad or NULL when an old reference to a
* ghostpad is used.
*
* MT safe.
*/
GstPad *
gst_pad_realize (GstPad * pad)
{
GstRealPad *result;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_LOCK (pad);
result = GST_PAD_REALIZE (pad);
if (result && pad != GST_PAD_CAST (result)) {
gst_object_ref (GST_OBJECT (result));
GST_UNLOCK (pad);
/* no other thread could dispose this since we
* hold at least one ref */
gst_object_unref (GST_OBJECT (pad));
} else {
GST_UNLOCK (pad);
}
return GST_PAD_CAST (result);
}
/**
* gst_pad_get_allowed_caps:
* @srcpad: a #GstPad, it must a a source pad.
*
* Gets the capabilities of the allowed media types that can flow through @pad
* and its peer. The pad must be a source pad.
* The caller must free the resulting caps.
*
* Returns: the allowed #GstCaps of the pad link. Free the caps when
* you no longer need it. This function returns NULL when the @pad has no
* peer.
*
* MT safe.
*/
GstCaps *
gst_pad_get_allowed_caps (GstPad * srcpad)
{
GstCaps *mycaps;
GstCaps *caps;
GstCaps *peercaps;
GstRealPad *realpad, *peer;
g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
GST_PAD_REALIZE_AND_LOCK (srcpad, realpad, lost_ghostpad);
if (G_UNLIKELY ((peer = GST_RPAD_PEER (realpad)) == NULL))
goto no_peer;
GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting allowed caps",
GST_DEBUG_PAD_NAME (realpad));
gst_object_ref (GST_OBJECT_CAST (peer));
GST_UNLOCK (realpad);
mycaps = gst_pad_get_caps (GST_PAD_CAST (realpad));
peercaps = gst_pad_get_caps (GST_PAD_CAST (peer));
gst_object_unref (GST_OBJECT_CAST (peer));
caps = gst_caps_intersect (mycaps, peercaps);
gst_caps_unref (peercaps);
gst_caps_unref (mycaps);
GST_CAT_DEBUG (GST_CAT_CAPS, "allowed caps %" GST_PTR_FORMAT, caps);
return caps;
lost_ghostpad:
{
GST_UNLOCK (srcpad);
return NULL;
}
no_peer:
{
GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
GST_DEBUG_PAD_NAME (realpad));
GST_UNLOCK (realpad);
return NULL;
}
}
/**
* gst_pad_get_negotiated_caps:
* @pad: a #GstPad.
*
* Gets the capabilities of the media type that currently flows through @pad
* and its peer.
*
* This function can be used on both src and sinkpads. Note that srcpads are
* always negotiated before sinkpads so it is possible that the negotiated caps
* on the srcpad do not match the negotiated caps of the peer.
*
* Returns: the negotiated #GstCaps of the pad link. Free the caps when
* you no longer need it. This function returns NULL when the @pad has no
* peer or is not negotiated yet.
*
* MT safe.
*/
GstCaps *
gst_pad_get_negotiated_caps (GstPad * pad)
{
GstCaps *caps;
GstRealPad *realpad, *peer;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
if (G_UNLIKELY ((peer = GST_RPAD_PEER (realpad)) == NULL))
goto no_peer;
GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting negotiated caps",
GST_DEBUG_PAD_NAME (realpad));
caps = GST_RPAD_CAPS (realpad);
if (caps)
gst_caps_ref (caps);
GST_UNLOCK (pad);
GST_CAT_DEBUG (GST_CAT_CAPS, "negotiated caps %" GST_PTR_FORMAT, caps);
return caps;
lost_ghostpad:
{
GST_UNLOCK (pad);
return NULL;
}
no_peer:
{
GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
GST_DEBUG_PAD_NAME (realpad));
GST_UNLOCK (realpad);
return NULL;
}
}
/**
* gst_pad_get_filter_caps:
* @pad: a real #GstPad.
*
* Gets the capabilities of filter that currently configured on @pad
* and its peer.
*
* Returns: the filter #GstCaps of the pad link. Free the caps when
* you no longer need it. This function returns NULL when the @pad has no
* peer or there is no filter configured.
*
* MT safe.
*/
GstCaps *
gst_pad_get_filter_caps (GstPad * pad)
{
GstCaps *caps;
GstRealPad *realpad, *peer;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_PAD_REALIZE_AND_LOCK (pad, realpad, lost_ghostpad);
if (G_UNLIKELY ((peer = GST_RPAD_PEER (realpad)) == NULL))
goto no_peer;
GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting filter caps",
GST_DEBUG_PAD_NAME (realpad));
if ((caps = GST_RPAD_APPFILTER (realpad)) != NULL)
gst_caps_ref (caps);
GST_UNLOCK (pad);
GST_CAT_DEBUG (GST_CAT_CAPS, "filter caps %" GST_PTR_FORMAT, caps);
return caps;
lost_ghostpad:
{
GST_UNLOCK (pad);
return NULL;
}
no_peer:
{
GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
GST_DEBUG_PAD_NAME (realpad));
GST_UNLOCK (realpad);
return NULL;
}
}
/**
* gst_pad_alloc_buffer:
* @pad: a source #GstPad
* @offset: the offset of the new buffer in the stream
* @size: the size of the new buffer
* @caps: the caps of the new buffer
*
* Allocates a new, empty buffer optimized to push to pad @pad. This
* function only works if @pad is a source pad and a GST_REAL_PAD and
* has a peer.
* You need to check the caps of the buffer after performing this
* function and renegotiate to the format if needed.
*
* Returns: a new, empty #GstBuffer, or NULL if wrong parameters
* were provided or the peer pad is not able to provide a buffer
* that can be handled by the caller.
*
* MT safe.
*/
GstBuffer *
gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps)
{
GstRealPad *peer;
GstBuffer *result = NULL;
GstPadBufferAllocFunction bufferallocfunc;
gboolean caps_changed;
g_return_val_if_fail (GST_IS_REAL_PAD (pad), NULL);
g_return_val_if_fail (GST_PAD_IS_SRC (pad), NULL);
GST_LOCK (pad);
if (G_UNLIKELY ((peer = GST_RPAD_PEER (pad)) == NULL))
goto no_peer;
if (G_LIKELY ((bufferallocfunc = peer->bufferallocfunc) == NULL)) {
GST_UNLOCK (pad);
goto fallback;
}
gst_object_ref (GST_OBJECT_CAST (peer));
GST_UNLOCK (pad);
GST_CAT_DEBUG (GST_CAT_PADS,
"calling bufferallocfunc &%s (@%p) of peer pad %s:%s",
GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
&bufferallocfunc, GST_DEBUG_PAD_NAME (peer));
result = bufferallocfunc (GST_PAD_CAST (peer), offset, size, caps);
gst_object_unref (GST_OBJECT_CAST (peer));
if (G_UNLIKELY (result == NULL)) {
goto fallback;
}
/* FIXME, move capnego this into a base class? */
caps = GST_BUFFER_CAPS (result);
caps_changed = caps && caps != GST_RPAD_CAPS (pad);
/* we got a new datatype on the pad, see if it can handle it */
if (G_UNLIKELY (caps_changed)) {
if (G_UNLIKELY (!gst_pad_configure_src (GST_PAD_CAST (pad), caps)))
goto not_negotiated;
}
return result;
no_peer:
{
/* pad has no peer */
GST_CAT_DEBUG (GST_CAT_PADS,
"%s:%s called bufferallocfunc but had no peer, returning NULL",
GST_DEBUG_PAD_NAME (pad));
GST_UNLOCK (pad);
return NULL;
}
/* fallback case, allocate a buffer of our own, add pad caps. */
fallback:
{
result = gst_buffer_new_and_alloc (size);
gst_buffer_set_caps (result, caps);
return result;
}
not_negotiated:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"alloc function retured unacceptable buffer");
return NULL;
}
}
static void
gst_real_pad_dispose (GObject * object)
{
GstPad *pad;
GstRealPad *rpad;
pad = GST_PAD (object);
rpad = GST_REAL_PAD (object);
/* No linked pad can ever be disposed.
* It has to have a parent to be linked
* and a parent would hold a reference */
/* FIXME: what about if g_object_dispose is explicitly called on the pad? Is
that legal? otherwise we could assert GST_OBJECT_PARENT (pad) == NULL as
well... */
g_assert (GST_PAD_PEER (pad) == NULL);
GST_CAT_DEBUG (GST_CAT_REFCOUNTING, "dispose %s:%s",
GST_DEBUG_PAD_NAME (pad));
/* we destroy the ghostpads, because they are nothing without the real pad */
if (rpad->ghostpads) {
GList *orig, *ghostpads;
orig = ghostpads = g_list_copy (rpad->ghostpads);
while (ghostpads) {
GstPad *ghostpad = GST_PAD (ghostpads->data);
if (GST_IS_ELEMENT (GST_OBJECT_PARENT (ghostpad))) {
GstElement *parent = GST_ELEMENT (GST_OBJECT_PARENT (ghostpad));
GST_CAT_DEBUG (GST_CAT_REFCOUNTING,
"removing ghost pad from element '%s'", GST_OBJECT_NAME (parent));
gst_element_remove_pad (parent, ghostpad);
} else {
/* handle the case where we have some floating ghost pad that was never
added to an element */
g_object_set (ghostpad, "real-pad", NULL, NULL);
}
ghostpads = g_list_next (ghostpads);
}
g_list_free (orig);
/* as the ghost pads are removed, they remove themselves from ->ghostpads.
So it should be empty now. Let's assert that. */
g_assert (rpad->ghostpads == NULL);
}
/* clear the caps */
gst_caps_replace (&GST_RPAD_CAPS (pad), NULL);
gst_caps_replace (&GST_RPAD_APPFILTER (pad), NULL);
if (GST_IS_ELEMENT (GST_OBJECT_PARENT (pad))) {
GST_CAT_DEBUG (GST_CAT_REFCOUNTING, "removing pad from element '%s'",
GST_OBJECT_NAME (GST_OBJECT (GST_ELEMENT (GST_OBJECT_PARENT (pad)))));
gst_element_remove_pad (GST_ELEMENT (GST_OBJECT_PARENT (pad)), pad);
}
G_OBJECT_CLASS (real_pad_parent_class)->dispose (object);
}
static void
gst_real_pad_finalize (GObject * object)
{
GstRealPad *rpad;
rpad = GST_REAL_PAD (object);
if (rpad->stream_rec_lock) {
g_static_rec_mutex_free (rpad->stream_rec_lock);
rpad->stream_rec_lock = NULL;
}
if (rpad->preroll_lock) {
g_mutex_free (rpad->preroll_lock);
g_cond_free (rpad->preroll_cond);
rpad->preroll_lock = NULL;
rpad->preroll_cond = NULL;
}
if (rpad->block_cond) {
g_cond_free (rpad->block_cond);
rpad->block_cond = NULL;
}
G_OBJECT_CLASS (real_pad_parent_class)->finalize (object);
}
#ifndef GST_DISABLE_LOADSAVE
/* FIXME: why isn't this on a GstElement ? */
/**
* gst_pad_load_and_link:
* @self: an #xmlNodePtr to read the description from.
* @parent: the #GstObject element that owns the pad.
*
* Reads the pad definition from the XML node and links the given pad
* in the element to a pad of an element up in the hierarchy.
*/
void
gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
{
xmlNodePtr field = self->xmlChildrenNode;
GstPad *pad = NULL, *targetpad;
gchar *peer = NULL;
gchar **split;
GstElement *target;
GstObject *grandparent;
gchar *name = NULL;
while (field) {
if (!strcmp (field->name, "name")) {
name = xmlNodeGetContent (field);
pad = gst_element_get_pad (GST_ELEMENT (parent), name);
g_free (name);
} else if (!strcmp (field->name, "peer")) {
peer = xmlNodeGetContent (field);
}
field = field->next;
}
g_return_if_fail (pad != NULL);
if (peer == NULL)
return;
split = g_strsplit (peer, ".", 2);
if (split[0] == NULL || split[1] == NULL) {
GST_CAT_DEBUG (GST_CAT_XML,
"Could not parse peer '%s' for pad %s:%s, leaving unlinked",
peer, GST_DEBUG_PAD_NAME (pad));
g_free (peer);
return;
}
g_free (peer);
g_return_if_fail (split[0] != NULL);
g_return_if_fail (split[1] != NULL);
grandparent = gst_object_get_parent (parent);
if (grandparent && GST_IS_BIN (grandparent)) {
target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
} else
goto cleanup;
if (target == NULL)
goto cleanup;
targetpad = gst_element_get_pad (target, split[1]);
if (targetpad == NULL)
goto cleanup;
gst_pad_link (pad, targetpad);
cleanup:
g_strfreev (split);
}
/**
* gst_pad_save_thyself:
* @pad: a #GstPad to save.
* @parent: the parent #xmlNodePtr to save the description in.
*
* Saves the pad into an xml representation.
*
* Returns: the #xmlNodePtr representation of the pad.
*/
static xmlNodePtr
gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
{
GstRealPad *realpad;
GstPad *peer;
g_return_val_if_fail (GST_IS_REAL_PAD (object), NULL);
realpad = GST_REAL_PAD (object);
xmlNewChild (parent, NULL, "name", GST_PAD_NAME (realpad));
if (GST_RPAD_PEER (realpad) != NULL) {
gchar *content;
peer = GST_PAD (GST_RPAD_PEER (realpad));
/* first check to see if the peer's parent's parent is the same */
/* we just save it off */
content = g_strdup_printf ("%s.%s",
GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
xmlNewChild (parent, NULL, "peer", content);
g_free (content);
} else
xmlNewChild (parent, NULL, "peer", "");
return parent;
}
/**
* gst_ghost_pad_save_thyself:
* @pad: a ghost #GstPad to save.
* @parent: the parent #xmlNodePtr to save the description in.
*
* Saves the ghost pad into an xml representation.
*
* Returns: the #xmlNodePtr representation of the pad.
*/
xmlNodePtr
gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
{
xmlNodePtr self;
g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
self = xmlNewChild (parent, NULL, "ghostpad", NULL);
xmlNewChild (self, NULL, "name", GST_PAD_NAME (pad));
xmlNewChild (self, NULL, "parent", GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
/* FIXME FIXME FIXME! */
return self;
}
#endif /* GST_DISABLE_LOADSAVE */
/*
* should be called with pad lock held
*
* MT safe.
*/
static void
handle_pad_block (GstRealPad * pad)
{
GstPadBlockCallback callback;
gpointer user_data;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"signal block taken on pad %s:%s", GST_DEBUG_PAD_NAME (pad));
/* need to grab extra ref for the callbacks */
gst_object_ref (GST_OBJECT (pad));
callback = pad->block_callback;
if (callback) {
user_data = pad->block_data;
GST_UNLOCK (pad);
callback (GST_PAD_CAST (pad), TRUE, user_data);
GST_LOCK (pad);
} else {
GST_PAD_BLOCK_SIGNAL (pad);
}
while (GST_RPAD_IS_BLOCKED (pad))
GST_PAD_BLOCK_WAIT (pad);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
callback = pad->block_callback;
if (callback) {
user_data = pad->block_data;
GST_UNLOCK (pad);
callback (GST_PAD_CAST (pad), FALSE, user_data);
GST_LOCK (pad);
} else {
GST_PAD_BLOCK_SIGNAL (pad);
}
gst_object_unref (GST_OBJECT (pad));
}
/**
* gst_pad_push:
* @pad: a source #GstPad.
* @buffer: the #GstBuffer to push.
*
* Pushes a buffer to the peer of @pad. @pad must be linked.
*
* Returns: a #GstFlowReturn from the peer pad.
*
* MT safe.
*/
GstFlowReturn
gst_pad_push (GstPad * pad, GstBuffer * buffer)
{
GstRealPad *peer;
GstFlowReturn ret;
GstPadChainFunction chainfunc;
GstCaps *caps;
gboolean caps_changed;
g_return_val_if_fail (GST_IS_REAL_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_RPAD_DIRECTION (pad) == GST_PAD_SRC,
GST_FLOW_ERROR);
g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
GST_LOCK (pad);
while (G_UNLIKELY (GST_RPAD_IS_BLOCKED (pad)))
handle_pad_block (GST_REAL_PAD_CAST (pad));
if (G_UNLIKELY ((peer = GST_RPAD_PEER (pad)) == NULL))
goto not_linked;
if (G_UNLIKELY (!GST_RPAD_IS_ACTIVE (peer)))
goto not_active;
if (G_UNLIKELY (GST_RPAD_IS_FLUSHING (peer)))
goto flushing;
gst_object_ref (GST_OBJECT_CAST (peer));
GST_UNLOCK (pad);
/* FIXME, move capnego this into a base class? */
caps = GST_BUFFER_CAPS (buffer);
caps_changed = caps && caps != GST_RPAD_CAPS (peer);
/* we got a new datatype on the peer pad, see if it can handle it */
if (G_UNLIKELY (caps_changed)) {
if (G_UNLIKELY (!gst_pad_configure_sink (GST_PAD_CAST (peer), caps)))
goto not_negotiated;
}
/* NOTE: we read the peer chainfunc unlocked.
* we cannot hold the lock for the peer so we might send
* the data to the wrong function. This is not really a
* problem since functions are assigned at creation time
* and don't change that often... */
if (G_UNLIKELY ((chainfunc = peer->chainfunc) == NULL))
goto no_function;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"calling chainfunction &%s of peer pad %s:%s",
GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_DEBUG_PAD_NAME (peer));
ret = chainfunc (GST_PAD_CAST (peer), buffer);
gst_object_unref (GST_OBJECT_CAST (peer));
return ret;
/* ERROR recovery here */
not_linked:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but it was not linked");
GST_UNLOCK (pad);
return GST_FLOW_NOT_CONNECTED;
}
not_active:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but it was inactive");
GST_UNLOCK (pad);
return GST_FLOW_WRONG_STATE;
}
flushing:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but pad was flushing");
GST_UNLOCK (pad);
return GST_FLOW_UNEXPECTED;
}
not_negotiated:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing buffer but peer did not accept");
return GST_FLOW_NOT_NEGOTIATED;
}
no_function:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but not chainhandler");
GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
("push on pad %s:%s but the peer pad %s:%s has no chainfunction",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_PAD_NAME (peer)));
gst_object_unref (GST_OBJECT (peer));
return GST_FLOW_ERROR;
}
}
/**
* gst_pad_pull_range:
* @pad: a sink #GstPad.
* @buffer: a pointer to hold the #GstBuffer.
* @offset: The start offset of the buffer
* @length: The length of the buffer
*
* Pulls a buffer from the peer pad. @pad must be linked.
*
* Returns: a #GstFlowReturn from the peer pad.
*
* MT safe.
*/
GstFlowReturn
gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
GstBuffer ** buffer)
{
GstRealPad *peer;
GstFlowReturn ret;
GstPadGetRangeFunction getrangefunc;
g_return_val_if_fail (GST_IS_REAL_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_RPAD_DIRECTION (pad) == GST_PAD_SINK,
GST_FLOW_ERROR);
g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
GST_LOCK (pad);
while (G_UNLIKELY (GST_RPAD_IS_BLOCKED (pad)))
handle_pad_block (GST_REAL_PAD_CAST (pad));
if (G_UNLIKELY ((peer = GST_RPAD_PEER (pad)) == NULL))
goto not_connected;
gst_object_ref (GST_OBJECT_CAST (peer));
GST_UNLOCK (pad);
/* see note in above function */
if (G_UNLIKELY ((getrangefunc = peer->getrangefunc) == NULL))
goto no_function;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"calling getrangefunc %s of peer pad %s:%s",
GST_DEBUG_FUNCPTR_NAME (getrangefunc), GST_DEBUG_PAD_NAME (peer));
ret = getrangefunc (GST_PAD_CAST (peer), offset, size, buffer);
gst_object_unref (GST_OBJECT_CAST (peer));
return ret;
/* ERROR recovery here */
not_connected:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pulling range, but it was not linked");
GST_UNLOCK (pad);
return GST_FLOW_NOT_CONNECTED;
}
no_function:
{
GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
("pullrange on pad %s:%s but the peer pad %s:%s has no getrangefunction",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_PAD_NAME (peer)));
gst_object_unref (GST_OBJECT (peer));
return GST_FLOW_ERROR;
}
}
/************************************************************************
*
* templates
*
*/
static void gst_pad_template_class_init (GstPadTemplateClass * klass);
static void gst_pad_template_init (GstPadTemplate * templ);
static void gst_pad_template_dispose (GObject * object);
GType
gst_pad_template_get_type (void)
{
static GType padtemplate_type = 0;
if (!padtemplate_type) {
static const GTypeInfo padtemplate_info = {
sizeof (GstPadTemplateClass), NULL, NULL,
(GClassInitFunc) gst_pad_template_class_init, NULL, NULL,
sizeof (GstPadTemplate),
0,
(GInstanceInitFunc) gst_pad_template_init, NULL
};
padtemplate_type =
g_type_register_static (GST_TYPE_OBJECT, "GstPadTemplate",
&padtemplate_info, 0);
}
return padtemplate_type;
}
static void
gst_pad_template_class_init (GstPadTemplateClass * klass)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
gobject_class = (GObjectClass *) klass;
gstobject_class = (GstObjectClass *) klass;
padtemplate_parent_class = g_type_class_ref (GST_TYPE_OBJECT);
gst_pad_template_signals[TEMPL_PAD_CREATED] =
g_signal_new ("pad-created", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstPadTemplateClass, pad_created),
NULL, NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
gobject_class->dispose = gst_pad_template_dispose;
gstobject_class->path_string_separator = "*";
}
static void
gst_pad_template_init (GstPadTemplate * templ)
{
}
static void
gst_pad_template_dispose (GObject * object)
{
GstPadTemplate *templ = GST_PAD_TEMPLATE (object);
g_free (GST_PAD_TEMPLATE_NAME_TEMPLATE (templ));
if (GST_PAD_TEMPLATE_CAPS (templ)) {
gst_caps_unref (GST_PAD_TEMPLATE_CAPS (templ));
}
G_OBJECT_CLASS (padtemplate_parent_class)->dispose (object);
}
/* ALWAYS padtemplates cannot have conversion specifications, it doesn't make
* sense.
* SOMETIMES padtemplates can do whatever they want, they are provided by the
* element.
* REQUEST padtemplates can be reverse-parsed (the user asks for 'sink1', the
* 'sink%d' template is automatically selected), so we need to restrict their
* naming.
*/
static gboolean
name_is_valid (const gchar * name, GstPadPresence presence)
{
const gchar *str;
if (presence == GST_PAD_ALWAYS) {
if (strchr (name, '%')) {
g_warning ("invalid name template %s: conversion specifications are not"
" allowed for GST_PAD_ALWAYS padtemplates", name);
return FALSE;
}
} else if (presence == GST_PAD_REQUEST) {
if ((str = strchr (name, '%')) && strchr (str + 1, '%')) {
g_warning ("invalid name template %s: only one conversion specification"
" allowed in GST_PAD_REQUEST padtemplate", name);
return FALSE;
}
if (str && (*(str + 1) != 's' && *(str + 1) != 'd')) {
g_warning ("invalid name template %s: conversion specification must be of"
" type '%%d' or '%%s' for GST_PAD_REQUEST padtemplate", name);
return FALSE;
}
if (str && (*(str + 2) != '\0')) {
g_warning ("invalid name template %s: conversion specification must"
" appear at the end of the GST_PAD_REQUEST padtemplate name", name);
return FALSE;
}
}
return TRUE;
}
/**
* gst_static_pad_template_get:
* @pad_template: the static pad template
*
* Converts a #GstStaticPadTemplate into a #GstPadTemplate.
*
* Returns: a new #GstPadTemplate.
*/
GstPadTemplate *
gst_static_pad_template_get (GstStaticPadTemplate * pad_template)
{
GstPadTemplate *new;
if (!name_is_valid (pad_template->name_template, pad_template->presence))
return NULL;
new = g_object_new (gst_pad_template_get_type (),
"name", pad_template->name_template, NULL);
GST_PAD_TEMPLATE_NAME_TEMPLATE (new) = g_strdup (pad_template->name_template);
GST_PAD_TEMPLATE_DIRECTION (new) = pad_template->direction;
GST_PAD_TEMPLATE_PRESENCE (new) = pad_template->presence;
GST_PAD_TEMPLATE_CAPS (new) =
gst_caps_copy (gst_static_caps_get (&pad_template->static_caps));
return new;
}
/**
* gst_pad_template_new:
* @name_template: the name template.
* @direction: the #GstPadDirection of the template.
* @presence: the #GstPadPresence of the pad.
* @caps: a #GstCaps set for the template. The caps are taken ownership of.
*
* Creates a new pad template with a name according to the given template
* and with the given arguments. This functions takes ownership of the provided
* caps, so be sure to not use them afterwards.
*
* Returns: a new #GstPadTemplate.
*/
GstPadTemplate *
gst_pad_template_new (const gchar * name_template,
GstPadDirection direction, GstPadPresence presence, GstCaps * caps)
{
GstPadTemplate *new;
g_return_val_if_fail (name_template != NULL, NULL);
g_return_val_if_fail (caps != NULL, NULL);
g_return_val_if_fail (direction == GST_PAD_SRC
|| direction == GST_PAD_SINK, NULL);
g_return_val_if_fail (presence == GST_PAD_ALWAYS
|| presence == GST_PAD_SOMETIMES || presence == GST_PAD_REQUEST, NULL);
if (!name_is_valid (name_template, presence))
return NULL;
new = g_object_new (gst_pad_template_get_type (),
"name", name_template, NULL);
GST_PAD_TEMPLATE_NAME_TEMPLATE (new) = g_strdup (name_template);
GST_PAD_TEMPLATE_DIRECTION (new) = direction;
GST_PAD_TEMPLATE_PRESENCE (new) = presence;
GST_PAD_TEMPLATE_CAPS (new) = caps;
return new;
}
/**
* gst_pad_template_get_caps:
* @templ: a #GstPadTemplate to get capabilities of.
*
* Gets the capabilities of the pad template.
*
* Returns: the #GstCaps of the pad template. If you need to keep a reference to
* the caps, make a copy (see gst_caps_copy ()).
*/
const GstCaps *
gst_pad_template_get_caps (GstPadTemplate * templ)
{
g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
return GST_PAD_TEMPLATE_CAPS (templ);
}
/**
* gst_pad_set_element_private:
* @pad: the #GstPad to set the private data of.
* @priv: The private data to attach to the pad.
*
* Set the given private data gpointer on the pad.
* This function can only be used by the element that owns the pad.
*/
void
gst_pad_set_element_private (GstPad * pad, gpointer priv)
{
pad->element_private = priv;
}
/**
* gst_pad_get_element_private:
* @pad: the #GstPad to get the private data of.
*
* Gets the private data of a pad.
*
* Returns: a #gpointer to the private data.
*/
gpointer
gst_pad_get_element_private (GstPad * pad)
{
return pad->element_private;
}
/***** ghost pads *****/
GType _gst_ghost_pad_type = 0;
static void gst_ghost_pad_class_init (GstGhostPadClass * klass);
static void gst_ghost_pad_init (GstGhostPad * pad);
static void gst_ghost_pad_dispose (GObject * object);
static void gst_ghost_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_ghost_pad_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static GstPad *ghost_pad_parent_class = NULL;
/* static guint gst_ghost_pad_signals[LAST_SIGNAL] = { 0 }; */
enum
{
GPAD_ARG_0,
GPAD_ARG_REAL_PAD
/* fill me */
};
GType
gst_ghost_pad_get_type (void)
{
if (!_gst_ghost_pad_type) {
static const GTypeInfo pad_info = {
sizeof (GstGhostPadClass), NULL, NULL,
(GClassInitFunc) gst_ghost_pad_class_init, NULL, NULL,
sizeof (GstGhostPad),
0,
(GInstanceInitFunc) gst_ghost_pad_init,
NULL
};
_gst_ghost_pad_type = g_type_register_static (GST_TYPE_PAD, "GstGhostPad",
&pad_info, 0);
}
return _gst_ghost_pad_type;
}
static void
gst_ghost_pad_class_init (GstGhostPadClass * klass)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass *) klass;
ghost_pad_parent_class = g_type_class_ref (GST_TYPE_PAD);
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_ghost_pad_dispose);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_ghost_pad_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_ghost_pad_get_property);
g_object_class_install_property (gobject_class, GPAD_ARG_REAL_PAD,
g_param_spec_object ("real-pad", "Real pad",
"The real pad for the ghost pad", GST_TYPE_PAD, G_PARAM_READWRITE));
}
static void
gst_ghost_pad_init (GstGhostPad * pad)
{
/* zeroed by glib */
}
static void
gst_ghost_pad_dispose (GObject * object)
{
g_object_set (object, "real-pad", NULL, NULL);
G_OBJECT_CLASS (ghost_pad_parent_class)->dispose (object);
}
static void
gst_ghost_pad_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstPad *ghostpad = (GstPad *) object;
GstPad *oldrealpad = (GstPad *) GST_GPAD_REALPAD (ghostpad);
GstPad *realpad = NULL;
switch (prop_id) {
case GPAD_ARG_REAL_PAD:
realpad = g_value_get_object (value);
if (oldrealpad) {
if (realpad == oldrealpad)
return;
else
gst_pad_remove_ghost_pad (oldrealpad, ghostpad);
}
if (realpad)
gst_pad_add_ghost_pad (realpad, ghostpad);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_ghost_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
switch (prop_id) {
case GPAD_ARG_REAL_PAD:
g_value_set_object (value, GST_GPAD_REALPAD (object));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/**
* gst_ghost_pad_new:
* @name: the name of the new ghost pad.
* @pad: the #GstPad to create a ghost pad for.
*
* Creates a new ghost pad associated with @pad, and named @name. If @name is
* %NULL, a guaranteed unique name (across all ghost pads) will be assigned.
*
* Returns: a new ghost #GstPad, or %NULL in case of an error.
*/
GstPad *
gst_ghost_pad_new (const gchar * name, GstPad * pad)
{
GstPad *gpad;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
gpad = g_object_new (GST_TYPE_GHOST_PAD, "name", name, "real-pad", pad, NULL);
GST_CAT_DEBUG (GST_CAT_PADS, "created ghost pad \"%s\" for pad %s:%s",
GST_OBJECT_NAME (gpad), GST_DEBUG_PAD_NAME (pad));
return gpad;
}
/**
* gst_pad_get_internal_links_default:
* @pad: the #GstPad to get the internal links of.
*
* Gets a list of pads to which the given pad is linked to
* inside of the parent element.
* This is the default handler, and thus returns a list of all of the
* pads inside the parent element with opposite direction.
* The caller must free this list after use.
*
* Returns: a newly allocated #GList of pads.
*/
GList *
gst_pad_get_internal_links_default (GstPad * pad)
{
GList *res = NULL;
GstElement *parent;
GList *parent_pads;
GstPadDirection direction;
GstRealPad *rpad;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
rpad = GST_PAD_REALIZE (pad);
direction = rpad->direction;
parent = GST_PAD_PARENT (rpad);
parent_pads = parent->pads;
while (parent_pads) {
GstRealPad *parent_pad = GST_PAD_REALIZE (parent_pads->data);
if (parent_pad->direction != direction) {
res = g_list_prepend (res, parent_pad);
}
parent_pads = g_list_next (parent_pads);
}
return res;
}
/**
* gst_pad_get_internal_links:
* @pad: the #GstPad to get the internal links of.
*
* Gets a list of pads to which the given pad is linked to
* inside of the parent element.
* The caller must free this list after use.
*
* Returns: a newly allocated #GList of pads.
*/
GList *
gst_pad_get_internal_links (GstPad * pad)
{
GList *res = NULL;
GstRealPad *rpad;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
rpad = GST_PAD_REALIZE (pad);
if (GST_RPAD_INTLINKFUNC (rpad))
res = GST_RPAD_INTLINKFUNC (rpad) (GST_PAD_CAST (rpad));
return res;
}
static gboolean
gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
{
GList *orig, *pads;
gboolean result;
GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
event);
result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
orig = pads = gst_pad_get_internal_links (pad);
while (pads) {
GstPad *eventpad = GST_PAD (pads->data);
pads = g_list_next (pads);
/* for all of the internally-linked pads that are actually linked */
if (GST_PAD_IS_LINKED (eventpad)) {
if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
/* for each pad we send to, we should ref the event; it's up
* to downstream to unref again when handled. */
GST_LOG_OBJECT (pad, "Reffing and sending event %p to %s:%s", event,
GST_DEBUG_PAD_NAME (eventpad));
gst_event_ref (event);
gst_pad_push_event (eventpad, event);
} else {
/* we only send the event on one pad, multi-sinkpad elements
* should implement a handler */
GST_LOG_OBJECT (pad, "sending event %p to one sink pad %s:%s", event,
GST_DEBUG_PAD_NAME (eventpad));
result = gst_pad_push_event (eventpad, event);
goto done;
}
}
}
/* we handled the incoming event so we unref once */
GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
gst_event_unref (event);
done:
g_list_free (orig);
return result;
}
/**
* gst_pad_event_default:
* @pad: a #GstPad to call the default event handler on.
* @event: the #GstEvent to handle.
*
* Invokes the default event handler for the given pad. End-of-stream and
* discontinuity events are handled specially, and then the event is sent to all
* pads internally linked to @pad. Note that if there are many possible sink
* pads that are internally linked to @pad, only one will be sent an event.
* Multi-sinkpad elements should implement custom event handlers.
*
* Returns: TRUE if the event was sent succesfully.
*/
gboolean
gst_pad_event_default (GstPad * pad, GstEvent * event)
{
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_EOS:
{
GstRealPad *rpad = GST_PAD_REALIZE (pad);
if (GST_RPAD_TASK (rpad)) {
GST_DEBUG_OBJECT (rpad, "pausing task because of eos");
gst_task_pause (GST_RPAD_TASK (rpad));
}
}
return gst_pad_event_default_dispatch (pad, event);
default:
return gst_pad_event_default_dispatch (pad, event);
}
}
/**
* gst_pad_dispatcher:
* @pad: a #GstPad to dispatch.
* @dispatch: the #GstDispatcherFunction to call.
* @data: gpointer user data passed to the dispatcher function.
*
* Invokes the given dispatcher function on all pads that are
* internally linked to the given pad.
* The GstPadDispatcherFunction should return TRUE when no further pads
* need to be processed.
*
* Returns: TRUE if one of the dispatcher functions returned TRUE.
*/
gboolean
gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
gpointer data)
{
gboolean res = FALSE;
GList *int_pads, *orig;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (dispatch != NULL, FALSE);
orig = int_pads = gst_pad_get_internal_links (pad);
while (int_pads) {
GstRealPad *int_rpad = GST_PAD_REALIZE (int_pads->data);
GstRealPad *int_peer = GST_RPAD_PEER (int_rpad);
if (int_peer) {
res = dispatch (GST_PAD (int_peer), data);
if (res)
break;
}
int_pads = g_list_next (int_pads);
}
g_list_free (orig);
return res;
}
/**
* gst_pad_push_event:
* @pad: a #GstPad to push the event to.
* @event: the #GstEvent to send to the pad.
*
* Sends the event to the peer of the given pad.
*
* Returns: TRUE if the event was handled.
*
* MT safe.
*/
gboolean
gst_pad_push_event (GstPad * pad, GstEvent * event)
{
GstRealPad *peerpad;
gboolean result;
g_return_val_if_fail (GST_IS_REAL_PAD (pad), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
GST_LOCK (pad);
peerpad = GST_RPAD_PEER (pad);
if (peerpad == NULL)
goto not_linked;
gst_object_ref (GST_OBJECT_CAST (peerpad));
GST_UNLOCK (pad);
result = gst_pad_send_event (GST_PAD_CAST (peerpad), event);
gst_object_unref (GST_OBJECT_CAST (peerpad));
return result;
/* ERROR handling */
not_linked:
{
GST_UNLOCK (pad);
return FALSE;
}
}
/**
* gst_pad_send_event:
* @pad: a #GstPad to send the event to.
* @event: the #GstEvent to send to the pad.
*
* Sends the event to the pad. This function can be used
* by applications to send events in the pipeline.
*
* Returns: TRUE if the event was handled.
*/
gboolean
gst_pad_send_event (GstPad * pad, GstEvent * event)
{
gboolean result = FALSE;
GstRealPad *rpad;
GstPadEventFunction eventfunc;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
rpad = GST_PAD_REALIZE (pad);
if (GST_EVENT_SRC (event) == NULL)
GST_EVENT_SRC (event) = gst_object_ref (GST_OBJECT (rpad));
GST_CAT_DEBUG (GST_CAT_EVENT, "have event type %d on pad %s:%s",
GST_EVENT_TYPE (event), GST_DEBUG_PAD_NAME (rpad));
if (GST_PAD_IS_SINK (pad)) {
if (GST_EVENT_TYPE (event) == GST_EVENT_FLUSH) {
GST_CAT_DEBUG (GST_CAT_EVENT, "have flush event");
GST_LOCK (pad);
if (GST_EVENT_FLUSH_DONE (event)) {
GST_CAT_DEBUG (GST_CAT_EVENT, "clear flush flag");
GST_FLAG_UNSET (pad, GST_PAD_FLUSHING);
} else {
GST_CAT_DEBUG (GST_CAT_EVENT, "set flush flag");
GST_FLAG_SET (pad, GST_PAD_FLUSHING);
}
GST_UNLOCK (pad);
}
}
if ((eventfunc = GST_RPAD_EVENTFUNC (rpad)) == NULL)
goto no_function;
result = eventfunc (GST_PAD_CAST (rpad), event);
return result;
/* ERROR handling */
no_function:
{
g_warning ("pad %s:%s has no event handler, file a bug.",
GST_DEBUG_PAD_NAME (rpad));
gst_event_unref (event);
return FALSE;
}
}
typedef struct
{
GstFormat src_format;
gint64 src_value;
GstFormat *dest_format;
gint64 *dest_value;
}
GstPadConvertData;
static gboolean
gst_pad_convert_dispatcher (GstPad * pad, GstPadConvertData * data)
{
return gst_pad_convert (pad, data->src_format, data->src_value,
data->dest_format, data->dest_value);
}
/**
* gst_pad_convert_default:
* @pad: a #GstPad to invoke the default 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 the default converter on a pad.
* This will forward the call to the pad obtained
* using the internal link of
* the element.
*
* Returns: TRUE if the conversion could be performed.
*/
gboolean
gst_pad_convert_default (GstPad * pad,
GstFormat src_format, gint64 src_value,
GstFormat * dest_format, gint64 * dest_value)
{
GstPadConvertData data;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (dest_format != NULL, FALSE);
g_return_val_if_fail (dest_value != NULL, FALSE);
data.src_format = src_format;
data.src_value = src_value;
data.dest_format = dest_format;
data.dest_value = dest_value;
return gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
gst_pad_convert_dispatcher, &data);
}
/**
* gst_pad_convert:
* @pad: a #GstPad to invoke the default 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 pad.
*
* Returns: TRUE if the conversion could be performed.
*/
gboolean
gst_pad_convert (GstPad * pad,
GstFormat src_format, gint64 src_value,
GstFormat * dest_format, gint64 * dest_value)
{
GstRealPad *rpad;
g_return_val_if_fail (GST_IS_PAD (pad), 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;
}
rpad = GST_PAD_REALIZE (pad);
if (GST_RPAD_CONVERTFUNC (rpad)) {
return GST_RPAD_CONVERTFUNC (rpad) (GST_PAD (rpad), src_format,
src_value, dest_format, dest_value);
}
return FALSE;
}
typedef struct
{
GstQueryType type;
GstFormat *format;
gint64 *value;
}
GstPadQueryData;
static gboolean
gst_pad_query_dispatcher (GstPad * pad, GstPadQueryData * data)
{
return gst_pad_query (pad, data->type, data->format, data->value);
}
/**
* gst_pad_query_default:
* @pad: a #GstPad to invoke the default query on.
* @type: the #GstQueryType of the query to perform.
* @format: a pointer to the #GstFormat of the result.
* @value: a pointer to the result.
*
* Invokes the default query function on a pad.
*
* Returns: TRUE if the query could be performed.
*/
gboolean
gst_pad_query_default (GstPad * pad, GstQueryType type,
GstFormat * format, gint64 * value)
{
GstPadQueryData data;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (format != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
data.type = type;
data.format = format;
data.value = value;
return gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
gst_pad_query_dispatcher, &data);
}
/**
* gst_pad_query:
* @pad: a #GstPad to invoke the default query on.
* @type: the #GstQueryType of the query to perform.
* @format: a pointer to the #GstFormat asked for.
* On return contains the #GstFormat used.
* @value: a pointer to the result.
*
* Queries a pad for one of the available properties. The format will be
* adjusted to the actual format used when specifying formats such as
* GST_FORMAT_DEFAULT.
* FIXME: Tell if the format can be adjusted when specifying a definite format.
*
* Returns: TRUE if the query could be performed.
*/
gboolean
gst_pad_query (GstPad * pad, GstQueryType type,
GstFormat * format, gint64 * value)
{
GstRealPad *rpad;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (format != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
rpad = GST_PAD_REALIZE (pad);
g_return_val_if_fail (rpad, FALSE);
if (GST_RPAD_QUERYFUNC (rpad))
return GST_RPAD_QUERYFUNC (rpad) (GST_PAD_CAST (rpad), type, format, value);
return FALSE;
}
static gboolean
gst_pad_get_formats_dispatcher (GstPad * pad, const GstFormat ** data)
{
*data = gst_pad_get_formats (pad);
return TRUE;
}
/**
* gst_pad_get_formats_default:
* @pad: a #GstPad to query
*
* Invoke the default format dispatcher for the pad.
*
* Returns: An array of GstFormats ended with a 0 value.
*/
const GstFormat *
gst_pad_get_formats_default (GstPad * pad)
{
GstFormat *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
gst_pad_get_formats_dispatcher, &result);
return result;
}
/**
* gst_pad_get_formats:
* @pad: a #GstPad to query
*
* Gets the list of supported formats from the pad.
*
* Returns: An array of GstFormats ended with a 0 value.
*/
const GstFormat *
gst_pad_get_formats (GstPad * pad)
{
GstRealPad *rpad;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
rpad = GST_PAD_REALIZE (pad);
if (GST_RPAD_FORMATSFUNC (rpad))
return GST_RPAD_FORMATSFUNC (rpad) (GST_PAD (pad));
return NULL;
}