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gstreamer/gst/gstpad.c
Tim-Philipp Müller 1c389318ec gst/gstinfo.c: Fix locking order, handle NULL function values properly. 
Original commit message from CVS:
* gst/gstinfo.c: (_gst_debug_nameof_funcptr):
Fix locking order, handle NULL function values properly.
* gst/gstinfo.h:
Fix docs.
* gst/gstpad.c: (gst_pad_buffer_alloc_unchecked):
Initialised variable before using it and fix debug statement to
print the address of the function rather than the address of the
variable on the stack holding the address of the function.
2006-09-01 15:55:20 +00:00

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115 KiB
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/* 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.
*/
/**
* SECTION:gstpad
* @short_description: Object contained by elements that allows links to
* other elements
* @see_also: #GstPadTemplate, #GstElement, #GstEvent
*
* A #GstElement is linked to other elements via "pads", which are extremely
* light-weight generic link points.
* After two pads are retrieved from an element with gst_element_get_pad(),
* the pads can be link with gst_pad_link(). (For quick links,
* you can also use gst_element_link(), which will make the obvious
* link for you if it's straightforward.)
*
* Pads are typically created from a #GstPadTemplate with
* gst_pad_new_from_template().
*
* Pads have #GstCaps attached to it to describe the media type they are
* capable of dealing with. gst_pad_get_caps() and gst_pad_set_caps() are
* used to manipulate the caps of the pads.
* Pads created from a pad template cannot set capabilities that are
* incompatible with the pad template capabilities.
*
* Pads without pad templates can be created with gst_pad_new(),
* which takes a direction and a name as an argument. If the name is NULL,
* then a guaranteed unique name will be assigned to it.
*
* gst_pad_get_parent() will retrieve the #GstElement that owns the pad.
*
* A #GstElement creating a pad will typically use the various
* gst_pad_set_*_function() calls to register callbacks for various events
* on the pads.
*
* GstElements will use gst_pad_push() and gst_pad_pull_range() to push out
* or pull in a buffer.
*
* To send a #GstEvent on a pad, use gst_pad_send_event() and
* gst_pad_push_event().
*
* Last reviewed on 2006-07-06 (0.10.9)
*/
#include "gst_private.h"
#include "gstpad.h"
#include "gstpadtemplate.h"
#include "gstenumtypes.h"
#include "gstmarshal.h"
#include "gstutils.h"
#include "gstinfo.h"
#include "gsterror.h"
#include "gstvalue.h"
#include "glib-compat-private.h"
GST_DEBUG_CATEGORY_STATIC (debug_dataflow);
#define GST_CAT_DEFAULT GST_CAT_PADS
/* Pad signals and args */
enum
{
PAD_LINKED,
PAD_UNLINKED,
PAD_REQUEST_LINK,
PAD_HAVE_DATA,
/* FILL ME */
LAST_SIGNAL
};
enum
{
PAD_PROP_0,
PAD_PROP_CAPS,
PAD_PROP_DIRECTION,
PAD_PROP_TEMPLATE,
/* FILL ME */
};
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_finalize (GObject * object);
static void gst_pad_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static GstFlowReturn handle_pad_block (GstPad * pad);
static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
static gboolean gst_pad_activate_default (GstPad * pad);
static gboolean gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps);
#ifndef GST_DISABLE_LOADSAVE
static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
#endif
static GstObjectClass *parent_class = NULL;
static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
/* quarks for probe signals */
static GQuark buffer_quark;
static GQuark event_quark;
typedef struct
{
const gint ret;
const gchar *name;
GQuark quark;
} GstFlowQuarks;
static GstFlowQuarks flow_quarks[] = {
{GST_FLOW_CUSTOM_SUCCESS, "custom-success", 0},
{GST_FLOW_RESEND, "resend", 0},
{GST_FLOW_OK, "ok", 0},
{GST_FLOW_NOT_LINKED, "not-linked", 0},
{GST_FLOW_WRONG_STATE, "wrong-state", 0},
{GST_FLOW_UNEXPECTED, "unexpected", 0},
{GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
{GST_FLOW_ERROR, "error", 0},
{GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
{GST_FLOW_CUSTOM_ERROR, "custom-error", 0},
{0, NULL, 0}
};
/**
* gst_flow_get_name:
* @ret: a #GstFlowReturn to get the name of.
*
* Gets a string representing the given flow return.
*
* Returns: a static string with the name of the flow return.
*/
G_CONST_RETURN gchar *
gst_flow_get_name (GstFlowReturn ret)
{
gint i;
ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
for (i = 0; flow_quarks[i].name; i++) {
if (ret == flow_quarks[i].ret)
return flow_quarks[i].name;
}
return "unknown";
}
/**
* gst_flow_to_quark:
* @ret: a #GstFlowReturn to get the quark of.
*
* Get the unique quark for the given GstFlowReturn.
*
* Returns: the quark associated with the flow return or 0 if an
* invalid return was specified.
*/
GQuark
gst_flow_to_quark (GstFlowReturn ret)
{
gint i;
ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
for (i = 0; flow_quarks[i].name; i++) {
if (ret == flow_quarks[i].ret)
return flow_quarks[i].quark;
}
return 0;
}
GType
gst_pad_get_type (void)
{
static GType gst_pad_type = 0;
if (G_UNLIKELY (gst_pad_type == 0)) {
static const GTypeInfo pad_info = {
sizeof (GstPadClass), NULL, NULL,
(GClassInitFunc) gst_pad_class_init, NULL, NULL,
sizeof (GstPad),
0,
(GInstanceInitFunc) gst_pad_init, NULL
};
gint i;
gst_pad_type = g_type_register_static (GST_TYPE_OBJECT, "GstPad",
&pad_info, 0);
buffer_quark = g_quark_from_static_string ("buffer");
event_quark = g_quark_from_static_string ("event");
for (i = 0; flow_quarks[i].name; i++) {
flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name);
}
GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW",
GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads");
}
return gst_pad_type;
}
static gboolean
_gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
GValue * return_accu, const GValue * handler_return, gpointer dummy)
{
gboolean ret = g_value_get_boolean (handler_return);
GST_DEBUG ("accumulated %d", ret);
g_value_set_boolean (return_accu, ret);
return ret;
}
static gboolean
default_have_data (GstPad * pad, GstMiniObject * o)
{
return TRUE;
}
static void
gst_pad_class_init (GstPadClass * klass)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
gobject_class = G_OBJECT_CLASS (klass);
gstobject_class = GST_OBJECT_CLASS (klass);
parent_class = g_type_class_peek_parent (klass);
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pad_dispose);
gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_pad_finalize);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pad_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pad_get_property);
/**
* GstPad::linked:
* @pad: the pad that emitted the signal
* @peer: the peer pad that has been connected
*
* Signals that a pad has been linked to the peer pad.
*/
gst_pad_signals[PAD_LINKED] =
g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
/**
* GstPad::unlinked:
* @pad: the pad that emitted the signal
* @peer: the peer pad that has been disconnected
*
* Signals that a pad has been unlinked from the peer pad.
*/
gst_pad_signals[PAD_UNLINKED] =
g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
/**
* GstPad::request-link:
* @pad: the pad that emitted the signal
* @peer: the peer pad for which a connection is requested
*
* Signals that a pad connection has been requested.
*/
gst_pad_signals[PAD_REQUEST_LINK] =
g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
/**
* GstPad::have-data:
* @pad: the pad that emitted the signal
* @mini_obj: new data
*
* Signals that new data is available on the pad. This signal is used
* internally for implementing pad probes.
* See gst_pad_add_*_probe functions.
*
* Returns: %TRUE to keep the data, %FALSE to drop it
*/
gst_pad_signals[PAD_HAVE_DATA] =
g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
G_STRUCT_OFFSET (GstPadClass, have_data),
_gst_do_pass_data_accumulator,
NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
GST_TYPE_MINI_OBJECT);
g_object_class_install_property (gobject_class, PAD_PROP_CAPS,
g_param_spec_boxed ("caps", "Caps", "The capabilities of the pad",
GST_TYPE_CAPS, G_PARAM_READABLE));
g_object_class_install_property (gobject_class, PAD_PROP_DIRECTION,
g_param_spec_enum ("direction", "Direction", "The direction of the pad",
GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
/* FIXME, Make G_PARAM_CONSTRUCT_ONLY when we fix ghostpads. */
g_object_class_install_property (gobject_class, PAD_PROP_TEMPLATE,
g_param_spec_object ("template", "Template",
"The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
G_PARAM_READWRITE));
#ifndef GST_DISABLE_LOADSAVE
gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_pad_save_thyself);
#endif
gstobject_class->path_string_separator = ".";
klass->have_data = default_have_data;
}
static void
gst_pad_init (GstPad * pad)
{
GST_PAD_DIRECTION (pad) = GST_PAD_UNKNOWN;
GST_PAD_PEER (pad) = NULL;
GST_PAD_CHAINFUNC (pad) = NULL;
GST_PAD_LINKFUNC (pad) = NULL;
GST_PAD_CAPS (pad) = NULL;
GST_PAD_GETCAPSFUNC (pad) = NULL;
GST_PAD_ACTIVATEFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_activate_default);
GST_PAD_EVENTFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_event_default);
GST_PAD_QUERYTYPEFUNC (pad) =
GST_DEBUG_FUNCPTR (gst_pad_get_query_types_default);
GST_PAD_QUERYFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_query_default);
GST_PAD_INTLINKFUNC (pad) =
GST_DEBUG_FUNCPTR (gst_pad_get_internal_links_default);
GST_PAD_ACCEPTCAPSFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_acceptcaps_default);
pad->do_buffer_signals = 0;
pad->do_event_signals = 0;
/* FIXME, should be set flushing initially, see #339326 */
GST_PAD_UNSET_FLUSHING (pad);
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 ();
}
static void
gst_pad_dispose (GObject * object)
{
GstPad *pad = GST_PAD (object);
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pad, "dispose");
/* we don't hold a ref to the peer so we can just set the
* peer to NULL. */
GST_PAD_PEER (pad) = NULL;
/* clear the caps */
gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
gst_pad_set_pad_template (pad, NULL);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_pad_finalize (GObject * object)
{
GstPad *pad = GST_PAD (object);
GstTask *task;
/* in case the task is still around, clean it up */
if ((task = GST_PAD_TASK (pad))) {
gst_task_join (task);
GST_PAD_TASK (pad) = NULL;
gst_object_unref (task);
}
if (pad->stream_rec_lock) {
g_static_rec_mutex_free (pad->stream_rec_lock);
g_free (pad->stream_rec_lock);
pad->stream_rec_lock = NULL;
}
if (pad->preroll_lock) {
g_mutex_free (pad->preroll_lock);
g_cond_free (pad->preroll_cond);
pad->preroll_lock = NULL;
pad->preroll_cond = NULL;
}
if (pad->block_cond) {
g_cond_free (pad->block_cond);
pad->block_cond = NULL;
}
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_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 PAD_PROP_DIRECTION:
GST_PAD_DIRECTION (object) = g_value_get_enum (value);
break;
case PAD_PROP_TEMPLATE:
gst_pad_set_pad_template (GST_PAD_CAST (object),
(GstPadTemplate *) g_value_get_object (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
g_return_if_fail (GST_IS_PAD (object));
switch (prop_id) {
case PAD_PROP_CAPS:
GST_OBJECT_LOCK (object);
g_value_set_boxed (value, GST_PAD_CAPS (object));
GST_OBJECT_UNLOCK (object);
break;
case PAD_PROP_DIRECTION:
g_value_set_enum (value, GST_PAD_DIRECTION (object));
break;
case PAD_PROP_TEMPLATE:
g_value_set_object (value, GST_PAD_PAD_TEMPLATE (object));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/**
* gst_pad_new:
* @name: the name of the new pad.
* @direction: the #GstPadDirection of the pad.
*
* Creates a new 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 g_object_new (GST_TYPE_PAD,
"name", name, "direction", direction, NULL);
}
/**
* gst_pad_new_from_template:
* @templ: the pad template to use
* @name: the name of the element
*
* Creates a new 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)
{
g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
return g_object_new (GST_TYPE_PAD,
"name", name, "direction", templ->direction, "template", templ, NULL);
}
/**
* gst_pad_new_from_static_template:
* @templ: the #GstStaticPadTemplate to use
* @name: the name of the element
*
* Creates a new pad with the given name from the given static 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_static_template (GstStaticPadTemplate * templ,
const gchar * name)
{
GstPad *pad;
GstPadTemplate *template;
template = gst_static_pad_template_get (templ);
pad = gst_pad_new_from_template (template, name);
gst_object_unref (template);
return pad;
}
/**
* 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;
/* 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_OBJECT_LOCK (pad);
result = GST_PAD_DIRECTION (pad);
GST_OBJECT_UNLOCK (pad);
return result;
}
static gboolean
gst_pad_activate_default (GstPad * pad)
{
return gst_pad_activate_push (pad, TRUE);
}
static void
pre_activate (GstPad * pad, GstActivateMode new_mode)
{
switch (new_mode) {
case GST_ACTIVATE_PUSH:
case GST_ACTIVATE_PULL:
GST_OBJECT_LOCK (pad);
GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d, unset flushing",
new_mode);
GST_PAD_UNSET_FLUSHING (pad);
GST_PAD_ACTIVATE_MODE (pad) = new_mode;
GST_OBJECT_UNLOCK (pad);
break;
case GST_ACTIVATE_NONE:
GST_OBJECT_LOCK (pad);
GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE NONE, set flushing",
new_mode);
GST_PAD_SET_FLUSHING (pad);
/* unlock blocked pads so element can resume and stop */
GST_PAD_BLOCK_SIGNAL (pad);
GST_OBJECT_UNLOCK (pad);
break;
}
}
static void
post_activate (GstPad * pad, GstActivateMode new_mode)
{
switch (new_mode) {
case GST_ACTIVATE_PUSH:
case GST_ACTIVATE_PULL:
/* nop */
break;
case GST_ACTIVATE_NONE:
/* ensures that streaming stops */
GST_PAD_STREAM_LOCK (pad);
/* while we're at it set activation mode */
GST_OBJECT_LOCK (pad);
GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d", new_mode);
GST_PAD_ACTIVATE_MODE (pad) = new_mode;
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
break;
}
}
/**
* gst_pad_set_active:
* @pad: the #GstPad to activate or deactivate.
* @active: whether or not the pad should be active.
*
* Activates or deactivates the given pad.
* Normally called from within core state change functions.
*
* If @active, makes sure the pad is active. If it is already active, either in
* push or pull mode, just return. Otherwise dispatches to the pad's activate
* function to perform the actual activation.
*
* If not @active, checks the pad's current mode and calls
* gst_pad_activate_push() or gst_pad_activate_pull(), as appropriate, with a
* FALSE argument.
*
* Returns: #TRUE if the operation was successful.
*
* MT safe.
*/
gboolean
gst_pad_set_active (GstPad * pad, gboolean active)
{
GstActivateMode old;
gboolean ret = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
old = GST_PAD_ACTIVATE_MODE (pad);
GST_OBJECT_UNLOCK (pad);
if (active) {
switch (old) {
case GST_ACTIVATE_PUSH:
case GST_ACTIVATE_PULL:
ret = TRUE;
break;
case GST_ACTIVATE_NONE:
ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
break;
}
} else {
switch (old) {
case GST_ACTIVATE_PUSH:
ret = gst_pad_activate_push (pad, FALSE);
break;
case GST_ACTIVATE_PULL:
ret = gst_pad_activate_pull (pad, FALSE);
break;
case GST_ACTIVATE_NONE:
ret = TRUE;
break;
}
}
if (!ret) {
GST_OBJECT_LOCK (pad);
if (!active) {
g_critical ("Failed to deactivate pad %s:%s, very bad",
GST_DEBUG_PAD_NAME (pad));
} else {
GST_WARNING ("Failed to activate pad %s:%s", GST_DEBUG_PAD_NAME (pad));
}
GST_OBJECT_UNLOCK (pad);
}
return ret;
}
/**
* gst_pad_activate_pull:
* @pad: the #GstPad to activate or deactivate.
* @active: whether or not the pad should be active.
*
* Activates or deactivates the given pad in pull mode via dispatching to the
* pad's activatepullfunc. For use from within pad activation functions only.
* When called on sink pads, will first proxy the call to the peer pad, which is
* expected to activate its internally linked pads from within its activate_pull
* function.
*
* If you don't know what this is, you probably don't want to call it.
*
* Returns: TRUE if the operation was successful.
*
* MT safe.
*/
gboolean
gst_pad_activate_pull (GstPad * pad, gboolean active)
{
GstActivateMode old, new;
GstPad *peer;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
old = GST_PAD_ACTIVATE_MODE (pad);
GST_OBJECT_UNLOCK (pad);
if (active) {
switch (old) {
case GST_ACTIVATE_PULL:
goto was_ok;
case GST_ACTIVATE_PUSH:
/* pad was activate in the wrong direction, deactivate it
* and reactivate it in pull mode */
if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
goto deactivate_failed;
/* fallthrough, pad is deactivated now. */
case GST_ACTIVATE_NONE:
break;
}
} else {
switch (old) {
case GST_ACTIVATE_NONE:
goto was_ok;
case GST_ACTIVATE_PUSH:
/* pad was activated in the other direction, deactivate it
* in push mode, this should not happen... */
if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
goto deactivate_failed;
/* everything is fine now */
goto was_ok;
case GST_ACTIVATE_PULL:
break;
}
}
if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
if ((peer = gst_pad_get_peer (pad))) {
if (G_UNLIKELY (!gst_pad_activate_pull (peer, active)))
goto peer_failed;
gst_object_unref (peer);
}
} else {
if (G_UNLIKELY (GST_PAD_GETRANGEFUNC (pad) == NULL))
goto failure; /* Can't activate pull on a src without a
getrange function */
}
new = active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
pre_activate (pad, new);
if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
if (G_UNLIKELY (!GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active)))
goto failure;
} else {
/* can happen for sinks of passthrough elements */
}
post_activate (pad, new);
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
active ? "activated" : "deactivated");
return TRUE;
was_ok:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
active ? "activated" : "deactivated");
return TRUE;
}
deactivate_failed:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"failed to %s in switch to pull from mode %d",
(active ? "activate" : "deactivate"), old);
return FALSE;
}
peer_failed:
{
GST_OBJECT_LOCK (peer);
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
GST_OBJECT_UNLOCK (peer);
gst_object_unref (peer);
return FALSE;
}
failure:
{
GST_OBJECT_LOCK (pad);
GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
active ? "activate" : "deactivate");
GST_PAD_SET_FLUSHING (pad);
GST_PAD_ACTIVATE_MODE (pad) = old;
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
}
/**
* gst_pad_activate_push:
* @pad: the #GstPad to activate or deactivate.
* @active: whether the pad should be active or not.
*
* Activates or deactivates the given pad in push mode via dispatching to the
* pad's activatepushfunc. For use from within pad activation functions only.
*
* If you don't know what this is, you probably don't want to call it.
*
* Returns: %TRUE if the operation was successful.
*
* MT safe.
*/
gboolean
gst_pad_activate_push (GstPad * pad, gboolean active)
{
GstActivateMode old, new;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
active ? "activated" : "deactivated");
GST_OBJECT_LOCK (pad);
old = GST_PAD_ACTIVATE_MODE (pad);
GST_OBJECT_UNLOCK (pad);
if (active) {
switch (old) {
case GST_ACTIVATE_PUSH:
goto was_ok;
case GST_ACTIVATE_PULL:
/* pad was activate in the wrong direction, deactivate it
* an reactivate it in push mode */
if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
goto deactivate_failed;
/* fallthrough, pad is deactivated now. */
case GST_ACTIVATE_NONE:
break;
}
} else {
switch (old) {
case GST_ACTIVATE_NONE:
goto was_ok;
case GST_ACTIVATE_PULL:
/* pad was activated in the other direction, deactivate it
* in pull mode, this should not happen... */
if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
goto deactivate_failed;
/* everything is fine now */
goto was_ok;
case GST_ACTIVATE_PUSH:
break;
}
}
new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
pre_activate (pad, new);
if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
if (G_UNLIKELY (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active))) {
goto failure;
}
} else {
/* quite ok, element relies on state change func to prepare itself */
}
post_activate (pad, new);
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
active ? "activated" : "deactivated");
return TRUE;
was_ok:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
active ? "activated" : "deactivated");
return TRUE;
}
deactivate_failed:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"failed to %s in switch to push from mode %d",
(active ? "activate" : "deactivate"), old);
return FALSE;
}
failure:
{
GST_OBJECT_LOCK (pad);
GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
active ? "activate" : "deactivate");
GST_PAD_SET_FLUSHING (pad);
GST_PAD_ACTIVATE_MODE (pad) = old;
GST_OBJECT_UNLOCK (pad);
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;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_set_blocked_async:
* @pad: the #GstPad to block or unblock
* @blocked: boolean indicating whether the pad should be blocked or unblocked
* @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 happens right before the next
* attempt at pushing a buffer on the pad.
*
* 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 careful 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 = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
was_blocked = GST_PAD_IS_BLOCKED (pad);
if (G_UNLIKELY (was_blocked == blocked))
goto had_right_state;
if (blocked) {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
pad->block_callback = callback;
pad->block_data = user_data;
if (!callback) {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
GST_PAD_BLOCK_WAIT (pad);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
}
} else {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
pad->block_callback = callback;
pad->block_data = user_data;
if (callback) {
GST_PAD_BLOCK_SIGNAL (pad);
} else {
GST_PAD_BLOCK_SIGNAL (pad);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
GST_PAD_BLOCK_WAIT (pad);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
}
}
GST_OBJECT_UNLOCK (pad);
return TRUE;
had_right_state:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pad was in right state (%d)", was_blocked);
GST_OBJECT_UNLOCK (pad);
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;
g_return_val_if_fail (GST_IS_PAD (pad), result);
GST_OBJECT_LOCK (pad);
result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_set_activate_function:
* @pad: a #GstPad.
* @activate: the #GstPadActivateFunction to set.
*
* Sets the given activate function for @pad. The activate function will
* dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
* the actual activation. Only makes sense to set on sink pads.
*
* Call this function if your sink pad can start a pull-based task.
*/
void
gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_PAD_ACTIVATEFUNC (pad) = activate;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
GST_DEBUG_FUNCPTR_NAME (activate));
}
/**
* gst_pad_set_activatepull_function:
* @pad: a #GstPad.
* @activatepull: the #GstPadActivateModeFunction to set.
*
* Sets the given activate_pull function for the pad. An activate_pull function
* prepares the element and any upstream connections for pulling. See XXX
* part-activation.txt for details.
*/
void
gst_pad_set_activatepull_function (GstPad * pad,
GstPadActivateModeFunction activatepull)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (activatepull));
}
/**
* gst_pad_set_activatepush_function:
* @pad: a #GstPad.
* @activatepush: the #GstPadActivateModeFunction to set.
*
* Sets the given activate_push function for the pad. An activate_push function
* prepares the element for pushing. See XXX part-activation.txt for details.
*/
void
gst_pad_set_activatepush_function (GstPad * pad,
GstPadActivateModeFunction activatepush)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (activatepush));
}
/**
* gst_pad_set_chain_function:
* @pad: a 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. see #GstPadChainFunction for more details.
*/
void
gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
{
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
GST_PAD_CHAINFUNC (pad) = chain;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (chain));
}
/**
* gst_pad_set_getrange_function:
* @pad: a 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. see
* #GstPadGetRangeFunction for a description of the getrange function.
*/
void
gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
{
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
GST_PAD_GETRANGEFUNC (pad) = get;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
GST_DEBUG_FUNCPTR_NAME (get));
}
/**
* gst_pad_set_checkgetrange_function:
* @pad: a source #GstPad.
* @check: the #GstPadCheckGetRangeFunction to set.
*
* Sets the given checkgetrange function for the pad. Implement this function on
* a pad if you dynamically support getrange based scheduling on the pad.
*/
void
gst_pad_set_checkgetrange_function (GstPad * pad,
GstPadCheckGetRangeFunction check)
{
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
GST_PAD_CHECKGETRANGEFUNC (pad) = check;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
GST_DEBUG_FUNCPTR_NAME (check));
}
/**
* gst_pad_set_event_function:
* @pad: a 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_PAD (pad));
GST_PAD_EVENTFUNC (pad) = event;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
GST_DEBUG_FUNCPTR_NAME (event));
}
/**
* gst_pad_set_query_function:
* @pad: a #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_PAD (pad));
GST_PAD_QUERYFUNC (pad) = query;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (query));
}
/**
* gst_pad_set_query_type_function:
* @pad: a #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_PAD (pad));
GST_PAD_QUERYTYPEFUNC (pad) = type_func;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
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)
{
GstPadQueryTypeFunction func;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
goto no_func;
return func (pad);
no_func:
{
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 #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_PAD (pad));
GST_PAD_INTLINKFUNC (pad) = intlink;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
GST_DEBUG_FUNCPTR_NAME (intlink));
}
/**
* gst_pad_set_link_function:
* @pad: a #GstPad.
* @link: the #GstPadLinkFunction to set.
*
* Sets the given link function for the pad. It will be called when
* the pad is linked with another pad.
*
* 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.
*
* If @link is installed on a source pad, it should call the #GstPadLinkFunction
* of the peer sink pad, if present.
*/
void
gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_PAD_LINKFUNC (pad) = link;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (link));
}
/**
* gst_pad_set_unlink_function:
* @pad: a #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_PAD (pad));
GST_PAD_UNLINKFUNC (pad) = unlink;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (unlink));
}
/**
* gst_pad_set_getcaps_function:
* @pad: a #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_PAD (pad));
GST_PAD_GETCAPSFUNC (pad) = getcaps;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (getcaps));
}
/**
* gst_pad_set_acceptcaps_function:
* @pad: a #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. Setting the
* acceptcaps function to NULL restores the default behaviour of allowing
* any caps that matches the caps from gst_pad_get_caps.
*/
void
gst_pad_set_acceptcaps_function (GstPad * pad,
GstPadAcceptCapsFunction acceptcaps)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (acceptcaps));
}
/**
* gst_pad_set_fixatecaps_function:
* @pad: a #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_PAD (pad));
GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (fixatecaps));
}
/**
* gst_pad_set_setcaps_function:
* @pad: a #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 its 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_PAD (pad));
GST_PAD_SETCAPSFUNC (pad) = setcaps;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (setcaps));
}
/**
* gst_pad_set_bufferalloc_function:
* @pad: a 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_PAD (pad));
g_return_if_fail (GST_PAD_IS_SINK (pad));
GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
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)
{
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_OBJECT_LOCK (srcpad);
if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
goto not_srcpad;
GST_OBJECT_LOCK (sinkpad);
if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
goto not_sinkpad;
if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
goto not_linked_together;
if (GST_PAD_UNLINKFUNC (srcpad)) {
GST_PAD_UNLINKFUNC (srcpad) (srcpad);
}
if (GST_PAD_UNLINKFUNC (sinkpad)) {
GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
}
/* first clear peers */
GST_PAD_PEER (srcpad) = NULL;
GST_PAD_PEER (sinkpad) = NULL;
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
/* fire off a signal to each of the pads telling them
* that they've been unlinked */
g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
return TRUE;
not_srcpad:
{
g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
GST_OBJECT_UNLOCK (srcpad);
return FALSE;
}
not_sinkpad:
{
g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return FALSE;
}
not_linked_together:
{
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
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;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
result = (GST_PAD_PEER (pad) != NULL);
GST_OBJECT_UNLOCK (pad);
return result;
}
/* get the caps from both pads and see if the intersection
* is not empty.
*
* This function should be called with the pad LOCK on both
* pads
*/
static gboolean
gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
{
GstCaps *srccaps;
GstCaps *sinkcaps;
GstCaps *icaps;
srccaps = gst_pad_get_caps_unlocked (src);
sinkcaps = gst_pad_get_caps_unlocked (sink);
GST_CAT_DEBUG (GST_CAT_CAPS, "src caps %" GST_PTR_FORMAT, srccaps);
GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
/* if we have caps on both pads we can check the intersection. If one
* of the caps is NULL, we return TRUE. */
if (srccaps == NULL || sinkcaps == NULL)
goto done;
icaps = gst_caps_intersect (srccaps, sinkcaps);
gst_caps_unref (srccaps);
gst_caps_unref (sinkcaps);
if (icaps == NULL)
goto was_null;
GST_CAT_DEBUG (GST_CAT_CAPS,
"intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
if (gst_caps_is_empty (icaps))
goto was_empty;
gst_caps_unref (icaps);
done:
return TRUE;
/* incompatible cases */
was_null:
{
GST_CAT_DEBUG (GST_CAT_CAPS, "intersection gave NULL");
return FALSE;
}
was_empty:
{
GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is EMPTY");
gst_caps_unref (icaps);
return FALSE;
}
}
/* check if the grandparents of both pads are the same.
* This check is required so that we don't try to link
* pads from elements in different bins without ghostpads.
*
* The LOCK should be held on both pads
*/
static gboolean
gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
{
GstObject *psrc, *psink;
gboolean res = TRUE;
psrc = GST_OBJECT_PARENT (src);
psink = GST_OBJECT_PARENT (sink);
/* if one of the pads has no parent, we allow the link */
if (psrc && psink) {
/* if the parents are the same, we have a loop */
if (G_UNLIKELY (psrc == psink))
goto same_parents;
/* if they both have a parent, we check the grandparents */
psrc = gst_object_get_parent (psrc);
psink = gst_object_get_parent (psink);
if (G_UNLIKELY (psrc != psink)) {
/* if they have grandparents but they are not the same */
GST_CAT_DEBUG (GST_CAT_CAPS,
"pads have different grandparents %" GST_PTR_FORMAT " and %"
GST_PTR_FORMAT, psrc, psink);
res = FALSE;
}
if (psrc)
gst_object_unref (psrc);
if (psink)
gst_object_unref (psink);
}
done:
return res;
/* ERRORS */
same_parents:
{
GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
psrc);
res = FALSE;
goto done;
}
}
/* FIXME leftover from an attempt at refactoring... */
/* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
* the two pads will be locked in the srcpad, sinkpad order. */
static GstPadLinkReturn
gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
{
/* 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));
GST_OBJECT_LOCK (srcpad);
if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
goto not_srcpad;
if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
goto src_was_linked;
GST_OBJECT_LOCK (sinkpad);
if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
goto not_sinkpad;
if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
goto sink_was_linked;
/* check hierarchy, pads can only be linked if the grandparents
* are the same. */
if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
goto wrong_hierarchy;
/* check pad caps for non-empty intersection */
if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
goto no_format;
/* FIXME check pad scheduling for non-empty intersection */
return GST_PAD_LINK_OK;
not_srcpad:
{
g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WRONG_DIRECTION;
}
src_was_linked:
{
GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
GST_DEBUG_PAD_NAME (srcpad),
GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WAS_LINKED;
}
not_sinkpad:
{
g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WRONG_DIRECTION;
}
sink_was_linked:
{
GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
GST_DEBUG_PAD_NAME (sinkpad),
GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WAS_LINKED;
}
wrong_hierarchy:
{
GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WRONG_HIERARCHY;
}
no_format:
{
GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_NOFORMAT;
}
}
/**
* gst_pad_link:
* @srcpad: the source #GstPad to link.
* @sinkpad: the sink #GstPad to link.
*
* Links the source pad and the sink pad.
*
* Returns: A result code indicating if the connection worked or
* what went wrong.
*
* MT Safe.
*/
GstPadLinkReturn
gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
{
GstPadLinkReturn result;
/* prepare will also lock the two pads */
result = gst_pad_link_prepare (srcpad, sinkpad);
if (result != GST_PAD_LINK_OK)
goto prepare_failed;
/* must set peers before calling the link function */
GST_PAD_PEER (srcpad) = sinkpad;
GST_PAD_PEER (sinkpad) = srcpad;
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
/* FIXME released the locks here, concurrent thread might link
* something else. */
if (GST_PAD_LINKFUNC (srcpad)) {
/* this one will call the peer link function */
result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
} else if (GST_PAD_LINKFUNC (sinkpad)) {
/* if no source link function, we need to call the sink link
* function ourselves. */
result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
} else {
result = GST_PAD_LINK_OK;
}
GST_OBJECT_LOCK (srcpad);
GST_OBJECT_LOCK (sinkpad);
if (result == GST_PAD_LINK_OK) {
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
/* fire off a signal to each of the pads telling them
* that they've been linked */
g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
} else {
GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
GST_PAD_PEER (srcpad) = NULL;
GST_PAD_PEER (sinkpad) = NULL;
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
}
return result;
prepare_failed:
{
return result;
}
}
static void
gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
{
GstPadTemplate **template_p;
/* this function would need checks if it weren't static */
GST_OBJECT_LOCK (pad);
template_p = &pad->padtemplate;
gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
GST_OBJECT_UNLOCK (pad);
if (templ)
gst_pad_template_pad_created (templ, 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.
*
* FIXME: currently returns an unrefcounted padtemplate.
*/
GstPadTemplate *
gst_pad_get_pad_template (GstPad * pad)
{
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
return GST_PAD_PAD_TEMPLATE (pad);
}
/* should be called with the pad LOCK held */
/* refs the caps, so caller is responsible for getting it unreffed */
static GstCaps *
gst_pad_get_caps_unlocked (GstPad * pad)
{
GstCaps *result = NULL;
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
if (GST_PAD_GETCAPSFUNC (pad)) {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"dispatching to pad getcaps function");
GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
GST_OBJECT_UNLOCK (pad);
result = GST_PAD_GETCAPSFUNC (pad) (pad);
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
if (result == NULL) {
g_critical ("pad %s:%s returned NULL caps from getcaps function",
GST_DEBUG_PAD_NAME (pad));
} else {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"pad getcaps returned %" GST_PTR_FORMAT, result);
#ifndef G_DISABLE_ASSERT
/* check that the returned caps are a real subset of the template caps */
if (GST_PAD_PAD_TEMPLATE (pad)) {
const GstCaps *templ_caps =
GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
if (!gst_caps_is_subset (result, templ_caps)) {
GstCaps *temp;
GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
"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 (pad));
temp = gst_caps_intersect (templ_caps, result);
gst_caps_unref (result);
result = temp;
}
}
#endif
goto done;
}
}
if (GST_PAD_PAD_TEMPLATE (pad)) {
GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
result = GST_PAD_TEMPLATE_CAPS (templ);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
result);
result = gst_caps_ref (result);
goto done;
}
if (GST_PAD_CAPS (pad)) {
result = GST_PAD_CAPS (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"using pad caps %p %" GST_PTR_FORMAT, result, result);
result = gst_caps_ref (result);
goto done;
}
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
result = gst_caps_new_empty ();
done:
return result;
}
/**
* gst_pad_get_caps:
* @pad: a #GstPad to get the capabilities of.
*
* Gets the capabilities this pad can produce or consume.
* Note that this method doesn't necessarily return the caps set by
* gst_pad_set_caps() - use #GST_PAD_CAPS for that instead.
* gst_pad_get_caps returns all possible caps a pad can operate with, using
* the pad's get_caps function;
* this returns the pad template caps if not explicitly set.
*
* Returns: a newly allocated copy of the #GstCaps of this pad.
*
* MT safe.
*/
GstCaps *
gst_pad_get_caps (GstPad * pad)
{
GstCaps *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
result = gst_pad_get_caps_unlocked (pad);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* 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. this function returns NULL if there is no
* peer pad.
*/
GstCaps *
gst_pad_peer_get_caps (GstPad * pad)
{
GstPad *peerpad;
GstCaps *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
peerpad = GST_PAD_PEER (pad);
if (G_UNLIKELY (peerpad == NULL))
goto no_peer;
gst_object_ref (peerpad);
GST_OBJECT_UNLOCK (pad);
result = gst_pad_get_caps (peerpad);
gst_object_unref (peerpad);
return result;
no_peer:
{
GST_OBJECT_UNLOCK (pad);
return NULL;
}
}
static gboolean
fixate_value (GValue * dest, const GValue * src)
{
if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
g_value_init (dest, G_TYPE_INT);
g_value_set_int (dest, gst_value_get_int_range_min (src));
} else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
g_value_init (dest, G_TYPE_DOUBLE);
g_value_set_double (dest, gst_value_get_double_range_min (src));
} else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
} else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
GValue temp = { 0 };
gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
if (!fixate_value (dest, &temp))
gst_value_init_and_copy (dest, &temp);
g_value_unset (&temp);
} else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
gboolean res = FALSE;
guint n;
g_value_init (dest, GST_TYPE_ARRAY);
for (n = 0; n < gst_value_array_get_size (src); n++) {
GValue kid = { 0 };
const GValue *orig_kid = gst_value_array_get_value (src, n);
if (!fixate_value (&kid, orig_kid))
gst_value_init_and_copy (&kid, orig_kid);
else
res = TRUE;
gst_value_array_append_value (dest, &kid);
g_value_unset (&kid);
}
if (!res)
g_value_unset (dest);
return res;
} else {
return FALSE;
}
return TRUE;
}
static gboolean
gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
{
GstStructure *s = data;
GValue v = { 0 };
if (fixate_value (&v, value)) {
gst_structure_id_set_value (s, field_id, &v);
g_value_unset (&v);
}
return TRUE;
}
/**
* gst_pad_fixate_caps:
* @pad: a #GstPad to fixate
* @caps: the #GstCaps to fixate
*
* Fixate a caps on the given pad. Modifies the caps in place, so you should
* make sure that the caps are actually writable (see gst_caps_make_writable()).
*/
void
gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
{
GstPadFixateCapsFunction fixatefunc;
guint n;
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (caps != NULL);
if (gst_caps_is_fixed (caps))
return;
fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
if (fixatefunc) {
fixatefunc (pad, caps);
}
/* default fixation */
for (n = 0; n < gst_caps_get_size (caps); n++) {
GstStructure *s = gst_caps_get_structure (caps, n);
gst_structure_foreach (s, gst_pad_default_fixate, s);
}
}
/* Default accept caps implementation just checks against
* against the allowed caps for the pad */
static gboolean
gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
{
/* get the caps and see if it intersects to something
* not empty */
GstCaps *intersect;
GstCaps *allowed;
gboolean result = FALSE;
allowed = gst_pad_get_caps (pad);
if (allowed) {
intersect = gst_caps_intersect (allowed, caps);
result = !gst_caps_is_empty (intersect);
gst_caps_unref (allowed);
gst_caps_unref (intersect);
}
return result;
}
/**
* gst_pad_accept_caps:
* @pad: a #GstPad to check
* @caps: a #GstCaps to check on the pad
*
* 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)
{
gboolean result;
GstPadAcceptCapsFunction acceptfunc;
GstCaps *existing = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
/* any pad can be unnegotiated */
if (caps == NULL)
return TRUE;
/* lock for checking the existing caps */
GST_OBJECT_LOCK (pad);
acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
/* The current caps on a pad are trivially acceptable */
if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
if (caps == existing || gst_caps_is_equal (caps, existing))
goto is_same_caps;
}
GST_OBJECT_UNLOCK (pad);
if (G_LIKELY (acceptfunc)) {
/* we can call the function */
result = acceptfunc (pad, caps);
} else {
/* Only null if the element explicitly unset it */
result = gst_pad_acceptcaps_default (pad, caps);
}
return result;
is_same_caps:
{
GST_OBJECT_UNLOCK (pad);
return TRUE;
}
}
/**
* gst_pad_peer_accept_caps:
* @pad: a #GstPad to check the peer of
* @caps: a #GstCaps to check on the pad
*
* Check if the peer of @pad accepts @caps. If @pad has no peer, this function
* returns TRUE.
*
* Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
*/
gboolean
gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
{
GstPad *peerpad;
gboolean result;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
peerpad = GST_PAD_PEER (pad);
if (G_UNLIKELY (peerpad == NULL))
goto no_peer;
result = gst_pad_accept_caps (peerpad, caps);
GST_OBJECT_UNLOCK (pad);
return result;
no_peer:
{
GST_OBJECT_UNLOCK (pad);
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;
GstCaps *existing;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
GST_OBJECT_LOCK (pad);
existing = GST_PAD_CAPS (pad);
if (existing == caps)
goto was_ok;
if (gst_caps_is_equal (caps, existing))
goto setting_same_caps;
setcaps = GST_PAD_SETCAPSFUNC (pad);
/* call setcaps function to configure the pad only if the
* caps is not NULL */
if (setcaps != NULL && caps) {
if (!GST_PAD_IS_IN_SETCAPS (pad)) {
GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
GST_OBJECT_UNLOCK (pad);
if (!setcaps (pad, caps))
goto could_not_set;
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
} else {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
}
}
gst_caps_replace (&GST_PAD_CAPS (pad), caps);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %" GST_PTR_FORMAT, caps);
GST_OBJECT_UNLOCK (pad);
g_object_notify (G_OBJECT (pad), "caps");
return TRUE;
was_ok:
{
GST_OBJECT_UNLOCK (pad);
return TRUE;
}
setting_same_caps:
{
gst_caps_replace (&GST_PAD_CAPS (pad), caps);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
GST_OBJECT_UNLOCK (pad);
return TRUE;
}
/* ERRORS */
could_not_set:
{
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"caps %" GST_PTR_FORMAT " could not be set", caps);
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
}
static gboolean
gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
{
GstPadSetCapsFunction setcaps;
gboolean res;
setcaps = GST_PAD_SETCAPSFUNC (pad);
/* See if pad accepts the caps - only needed if
* no setcaps function */
if (setcaps == NULL)
if (!gst_pad_accept_caps (pad, caps))
goto not_accepted;
/* set caps on pad if call succeeds */
res = 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 res;
not_accepted:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"caps %" GST_PTR_FORMAT " not accepted", caps);
return FALSE;
}
}
/* returns TRUE if the src pad could be configured to accept the given caps */
static gboolean
gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
{
GstPadSetCapsFunction setcaps;
gboolean res;
setcaps = GST_PAD_SETCAPSFUNC (pad);
/* See if pad accepts the caps - only needed if
* no setcaps function */
if (setcaps == NULL)
if (!gst_pad_accept_caps (pad, caps))
goto not_accepted;
if (dosetcaps)
res = gst_pad_set_caps (pad, caps);
else
res = TRUE;
return res;
not_accepted:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"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)
{
GstPad *result;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
result = GST_PAD_PEER (pad);
if (result)
gst_object_ref (result);
GST_OBJECT_UNLOCK (pad);
return 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
* @srcpad 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 @srcpad has no
* peer.
*
* MT safe.
*/
GstCaps *
gst_pad_get_allowed_caps (GstPad * srcpad)
{
GstCaps *mycaps;
GstCaps *caps;
GstCaps *peercaps;
GstPad *peer;
g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
GST_OBJECT_LOCK (srcpad);
peer = GST_PAD_PEER (srcpad);
if (G_UNLIKELY (peer == NULL))
goto no_peer;
GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "getting allowed caps");
gst_object_ref (peer);
GST_OBJECT_UNLOCK (srcpad);
mycaps = gst_pad_get_caps (srcpad);
peercaps = gst_pad_get_caps (peer);
gst_object_unref (peer);
caps = gst_caps_intersect (mycaps, peercaps);
gst_caps_unref (peercaps);
gst_caps_unref (mycaps);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, srcpad, "allowed caps %" GST_PTR_FORMAT,
caps);
return caps;
no_peer:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "no peer");
GST_OBJECT_UNLOCK (srcpad);
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;
GstPad *peer;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
goto no_peer;
GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
caps = GST_PAD_CAPS (pad);
if (caps)
gst_caps_ref (caps);
GST_OBJECT_UNLOCK (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
caps);
return caps;
no_peer:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
GST_OBJECT_UNLOCK (pad);
return NULL;
}
}
/* calls the buffer_alloc function on the given pad */
static GstFlowReturn
gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
GstCaps * caps, GstBuffer ** buf)
{
GstFlowReturn ret;
GstPadBufferAllocFunction bufferallocfunc;
GST_OBJECT_LOCK (pad);
/* when the pad is flushing we cannot give a buffer */
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
bufferallocfunc = pad->bufferallocfunc;
if (offset == GST_BUFFER_OFFSET_NONE) {
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"calling bufferallocfunc &%s (@%p) for size %d offset NONE",
GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), bufferallocfunc, size);
} else {
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"calling bufferallocfunc &%s (@%p) of for size %d offset %"
G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
bufferallocfunc, size, offset);
}
GST_OBJECT_UNLOCK (pad);
/* G_LIKELY for now since most elements don't implement a buffer alloc
* function and there is no default alloc proxy function as this is usually
* not possible. */
if (G_LIKELY (bufferallocfunc == NULL))
goto fallback;
ret = bufferallocfunc (pad, offset, size, caps, buf);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto error;
/* no error, but NULL buffer means fallback to the default */
if (G_UNLIKELY (*buf == NULL))
goto fallback;
/* If the buffer alloc function didn't set up the caps like it should,
* do it for it */
if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
GST_WARNING_OBJECT (pad,
"Buffer allocation function did not set caps. Setting");
gst_buffer_set_caps (*buf, caps);
}
return ret;
flushing:
{
/* pad was flushing */
GST_OBJECT_UNLOCK (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
return GST_FLOW_WRONG_STATE;
}
error:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
return ret;
}
fallback:
{
/* fallback case, allocate a buffer of our own, add pad caps. */
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
*buf = gst_buffer_new_and_alloc (size);
GST_BUFFER_OFFSET (*buf) = offset;
gst_buffer_set_caps (*buf, caps);
return GST_FLOW_OK;
}
}
static GstFlowReturn
gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
{
GstPad *peer;
GstFlowReturn ret;
gboolean caps_changed;
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
GST_OBJECT_LOCK (pad);
while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
goto flushed;
if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
goto no_peer;
gst_object_ref (peer);
GST_OBJECT_UNLOCK (pad);
ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
gst_object_unref (peer);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto peer_error;
/* FIXME, move capnego this into a base class? */
caps = GST_BUFFER_CAPS (*buf);
/* Lock for checking caps, pretty pointless as the _pad_push() function might
* change it concurrently, one of the problems with automatic caps setting in
* pad_alloc_and_set_caps. Worst case, if does a check too much, but only when
* there is heavy renegotiation going on in both directions. */
GST_OBJECT_LOCK (pad);
caps_changed = caps && caps != GST_PAD_CAPS (pad);
GST_OBJECT_UNLOCK (pad);
/* we got a new datatype on the pad, see if it can handle it */
if (G_UNLIKELY (caps_changed)) {
GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, setcaps)))
goto not_negotiated;
}
return ret;
flushed:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
GST_OBJECT_UNLOCK (pad);
return ret;
}
no_peer:
{
/* pad has no peer */
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"called bufferallocfunc but had no peer");
GST_OBJECT_UNLOCK (pad);
return GST_FLOW_NOT_LINKED;
}
peer_error:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"alloc function returned error %s", gst_flow_get_name (ret));
return ret;
}
not_negotiated:
{
gst_buffer_unref (*buf);
*buf = NULL;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"alloc function returned unacceptable buffer");
return GST_FLOW_NOT_NEGOTIATED;
}
}
/**
* 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
* @buf: a newly allocated buffer
*
* Allocates a new, empty buffer optimized to push to pad @pad. This
* function only works if @pad is a source pad and has a peer.
*
* A new, empty #GstBuffer will be put in the @buf argument.
* You need to check the caps of the buffer after performing this
* function and renegotiate to the format if needed.
*
* Returns: a result code indicating success of the operation. Any
* result code other than #GST_FLOW_OK is an error and @buf should
* not be used.
* An error can occur if the pad is not connected or when the downstream
* peer elements cannot provide an acceptable buffer.
*
* MT safe.
*/
GstFlowReturn
gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
GstBuffer ** buf)
{
return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
}
/**
* gst_pad_alloc_buffer_and_set_caps:
* @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
* @buf: a newly allocated buffer
*
* In addition to the function gst_pad_alloc_buffer(), this function
* automatically calls gst_pad_set_caps() when the caps of the
* newly allocated buffer are different from the @pad caps.
*
* Returns: a result code indicating success of the operation. Any
* result code other than #GST_FLOW_OK is an error and @buf should
* not be used.
* An error can occur if the pad is not connected or when the downstream
* peer elements cannot provide an acceptable buffer.
*
* MT safe.
*/
GstFlowReturn
gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
GstCaps * caps, GstBuffer ** buf)
{
return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
}
/**
* 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, or NULL if the pad has no parent.
*
* Not MT safe.
*/
GList *
gst_pad_get_internal_links_default (GstPad * pad)
{
GList *res = NULL;
GstElement *parent;
GList *parent_pads;
GstPadDirection direction;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
direction = pad->direction;
parent = GST_PAD_PARENT (pad);
if (!parent)
return NULL;
parent_pads = parent->pads;
while (parent_pads) {
GstPad *parent_pad = GST_PAD_CAST (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.
*
* Not MT safe.
*/
GList *
gst_pad_get_internal_links (GstPad * pad)
{
GList *res = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
if (GST_PAD_INTLINKFUNC (pad))
res = GST_PAD_INTLINKFUNC (pad) (pad);
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_CAST (pads->data);
pads = g_list_next (pads);
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 (%s) to %s:%s",
event, GST_EVENT_TYPE_NAME (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 (%s) to one sink pad %s:%s",
event, GST_EVENT_TYPE_NAME (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:
{
GST_DEBUG_OBJECT (pad, "pausing task because of eos");
gst_pad_pause_task (pad);
}
default:
break;
}
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) {
GstPad *int_pad = GST_PAD_CAST (int_pads->data);
GstPad *int_peer = GST_PAD_PEER (int_pad);
if (int_peer) {
res = dispatch (int_peer, data);
if (res)
break;
}
int_pads = g_list_next (int_pads);
}
g_list_free (orig);
return res;
}
/**
* gst_pad_query:
* @pad: a #GstPad to invoke the default query on.
* @query: the #GstQuery to perform.
*
* Dispatches a query to a pad. The query should have been allocated by the
* caller via one of the type-specific allocation functions in gstquery.h. The
* element is responsible for filling the query with an appropriate response,
* which should then be parsed with a type-specific query parsing function.
*
* Again, the caller is responsible for both the allocation and deallocation of
* the query structure.
*
* Returns: TRUE if the query could be performed.
*/
gboolean
gst_pad_query (GstPad * pad, GstQuery * query)
{
GstPadQueryFunction func;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
GST_DEBUG_OBJECT (pad, "sending query %p", query);
if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
goto no_func;
return func (pad, query);
no_func:
{
GST_DEBUG_OBJECT (pad, "had no query function");
return FALSE;
}
}
/**
* gst_pad_query_default:
* @pad: a #GstPad to call the default query handler on.
* @query: the #GstQuery to handle.
*
* Invokes the default query handler for the given pad.
* The query 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 the query.
* Multi-sinkpad elements should implement custom query handlers.
*
* Returns: TRUE if the query was performed succesfully.
*/
gboolean
gst_pad_query_default (GstPad * pad, GstQuery * query)
{
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_POSITION:
case GST_QUERY_SEEKING:
case GST_QUERY_FORMATS:
case GST_QUERY_LATENCY:
case GST_QUERY_JITTER:
case GST_QUERY_RATE:
case GST_QUERY_CONVERT:
default:
return gst_pad_dispatcher
(pad, (GstPadDispatcherFunction) gst_pad_query, query);
}
}
#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 ((char *) field->name, "name")) {
name = (gchar *) xmlNodeGetContent (field);
pad = gst_element_get_pad (GST_ELEMENT (parent), name);
g_free (name);
} else if (!strcmp ((char *) field->name, "peer")) {
peer = (gchar *) 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_OBJECT (GST_CAT_XML, pad,
"Could not parse peer '%s', leaving unlinked", peer);
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)
{
GstPad *pad;
GstPad *peer;
g_return_val_if_fail (GST_IS_PAD (object), NULL);
pad = GST_PAD (object);
xmlNewChild (parent, NULL, (xmlChar *) "name",
(xmlChar *) GST_PAD_NAME (pad));
if (GST_PAD_PEER (pad) != NULL) {
gchar *content;
peer = GST_PAD_PEER (pad);
/* 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, (xmlChar *) "peer", (xmlChar *) content);
g_free (content);
} else
xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
return parent;
}
#if 0
/**
* 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, (xmlChar *) "ghostpad", NULL);
xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
xmlNewChild (self, NULL, (xmlChar *) "parent",
(xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
/* FIXME FIXME FIXME! */
return self;
}
#endif /* 0 */
#endif /* GST_DISABLE_LOADSAVE */
/*
* should be called with pad OBJECT_LOCK and STREAM_LOCK held.
* GST_PAD_IS_BLOCK (pad) == TRUE when this function is
* called.
*
* This function perform the pad blocking when an event, buffer push
* or buffer_alloc is performed on a _SRC_ pad. It blocks the
* streaming thread after informing the pad has been blocked.
*
* An application can with this method wait and block any streaming
* thread and perform operations such as seeking or linking.
*
* Two methods are available for notifying the application of the
* block:
* - the callback method, which happens in the STREAMING thread with
* the STREAM_LOCK held. With this method, the most usefull way of
* dealing with the callback is to post a message to the main thread
* where the pad block can then be handled outside of the streaming
* thread. With the last method one can perform all operations such
* as doing a state change, linking, unblocking, seeking etc on the
* pad.
* - the GCond signal method, which makes any thread unblock when
* the pad block happens.
*
* MT safe.
*/
static GstFlowReturn
handle_pad_block (GstPad * pad)
{
GstPadBlockCallback callback;
gpointer user_data;
GstFlowReturn ret = GST_FLOW_OK;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
/* flushing, don't bother trying to block and return WRONG_STATE
* right away */
if (GST_PAD_IS_FLUSHING (pad))
goto flushingnonref;
/* we grab an extra ref for the callbacks, this is probably not
* needed (callback code does not have a ref and cannot unref). I
* think this was done to make it possible to unref the element in
* the callback, which is in the end totally impossible as it
* requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
* all taken when calling this function. */
gst_object_ref (pad);
/* we either have a callback installed to notify the block or
* some other thread is doing a GCond wait. */
callback = pad->block_callback;
if (callback) {
/* there is a callback installed, call it. We release the
* lock so that the callback can do something usefull with the
* pad */
user_data = pad->block_data;
GST_OBJECT_UNLOCK (pad);
callback (pad, TRUE, user_data);
GST_OBJECT_LOCK (pad);
} else {
/* no callback, signal the thread that is doing a GCond wait
* if any. */
GST_PAD_BLOCK_SIGNAL (pad);
}
/* OBJECT_LOCK could have been released when we did the callback, which
* then could have made the pad unblock so we need to check the blocking
* condition again. */
while (GST_PAD_IS_BLOCKED (pad)) {
if (GST_PAD_IS_FLUSHING (pad))
goto flushing;
/* now we block the streaming thread. It can be unlocked when we
* deactivate the pad (which will also set the FLUSHING flag) or
* when the pad is unblocked. A flushing event will also unblock
* the pad after setting the FLUSHING flag. */
GST_PAD_BLOCK_WAIT (pad);
/* see if we got unlocked by a flush or not */
if (GST_PAD_IS_FLUSHING (pad))
goto flushing;
}
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
/* when we get here, the pad is unblocked again and we perform
* the needed unblock code. */
callback = pad->block_callback;
if (callback) {
/* we need to call the callback */
user_data = pad->block_data;
GST_OBJECT_UNLOCK (pad);
callback (pad, FALSE, user_data);
GST_OBJECT_LOCK (pad);
} else {
/* we need to signal the thread waiting on the GCond */
GST_PAD_BLOCK_SIGNAL (pad);
}
gst_object_unref (pad);
return ret;
flushingnonref:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
return GST_FLOW_WRONG_STATE;
}
flushing:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
gst_object_unref (pad);
return GST_FLOW_WRONG_STATE;
}
}
/**********************************************************************
* Data passing functions
*/
static gboolean
gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
{
GValue ret = { 0 };
GValue args[2] = { {0}, {0} };
gboolean res;
GQuark detail;
/* init */
g_value_init (&ret, G_TYPE_BOOLEAN);
g_value_set_boolean (&ret, TRUE);
g_value_init (&args[0], GST_TYPE_PAD);
g_value_set_object (&args[0], pad);
g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
gst_value_set_mini_object (&args[1], obj);
if (GST_IS_EVENT (obj))
detail = event_quark;
else
detail = buffer_quark;
/* actually emit */
g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
res = g_value_get_boolean (&ret);
/* clean up */
g_value_unset (&ret);
g_value_unset (&args[0]);
g_value_unset (&args[1]);
return res;
}
/* this is the chain function that does not perform the additional argument
* checking for that little extra speed.
*/
static inline GstFlowReturn
gst_pad_chain_unchecked (GstPad * pad, GstBuffer * buffer)
{
GstCaps *caps;
gboolean caps_changed;
GstPadChainFunction chainfunc;
GstFlowReturn ret;
gboolean emit_signal;
GST_PAD_STREAM_LOCK (pad);
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
caps = GST_BUFFER_CAPS (buffer);
caps_changed = caps && caps != GST_PAD_CAPS (pad);
emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
GST_OBJECT_UNLOCK (pad);
/* see if the signal should be emited, we emit before caps nego as
* we might drop the buffer and do capsnego for nothing. */
if (G_UNLIKELY (emit_signal)) {
if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
goto dropping;
}
/* we got a new datatype on the pad, see if it can handle it */
if (G_UNLIKELY (caps_changed)) {
GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
goto not_negotiated;
}
/* NOTE: we read the chainfunc unlocked.
* we cannot hold the lock for the pad 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 = GST_PAD_CHAINFUNC (pad)) == NULL))
goto no_function;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"calling chainfunction &%s", GST_DEBUG_FUNCPTR_NAME (chainfunc));
ret = chainfunc (pad, buffer);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"called chainfunction &%s, returned %s",
GST_DEBUG_FUNCPTR_NAME (chainfunc), gst_flow_get_name (ret));
GST_PAD_STREAM_UNLOCK (pad);
return ret;
/* ERRORS */
flushing:
{
gst_buffer_unref (buffer);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but pad was flushing");
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_WRONG_STATE;
}
dropping:
{
gst_buffer_unref (buffer);
GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_OK;
}
not_negotiated:
{
gst_buffer_unref (buffer);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing buffer but pad did not accept");
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_NOT_NEGOTIATED;
}
no_function:
{
gst_buffer_unref (buffer);
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 it has no chainfunction",
GST_DEBUG_PAD_NAME (pad)));
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_NOT_SUPPORTED;
}
}
/**
* gst_pad_chain:
* @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
* @buffer: the #GstBuffer to send, return GST_FLOW_ERROR if not.
*
* Chain a buffer to @pad.
*
* The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
*
* If the caps on @buffer are different from the current caps on @pad, this
* function will call any setcaps function (see gst_pad_set_setcaps_function())
* installed on @pad. If the new caps are not acceptable for @pad, this function
* returns #GST_FLOW_NOT_NEGOTIATED.
*
* The function proceeds calling the chain function installed on @pad (see
* gst_pad_set_chain_function()) and the return value of that function is
* returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
* chain function.
*
* In all cases, success or failure, the caller loses its reference to @buffer
* after calling this function.
*
* Returns: a #GstFlowReturn from the pad.
*
* MT safe.
*/
GstFlowReturn
gst_pad_chain (GstPad * pad, GstBuffer * buffer)
{
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
GST_FLOW_ERROR);
g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
return gst_pad_chain_unchecked (pad, buffer);
}
/**
* gst_pad_push:
* @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
* @buffer: the #GstBuffer to push returns GST_FLOW_ERROR if not.
*
* Pushes a buffer to the peer of @pad.
*
* This function will call an installed pad block before triggering any
* installed pad probes.
*
* If the caps on @buffer are different from the currently configured caps on
* @pad, this function will call any installed setcaps function on @pad (see
* gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
* format, this function returns #GST_FLOW_NOT_NEGOTIATED.
*
* The function proceeds calling gst_pad_chain() on the peer pad and returns the
* value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will be
* returned.
*
* In all cases, success or failure, the caller loses its reference to @buffer
* after calling this function.
*
* Returns: a #GstFlowReturn from the peer pad.
*
* MT safe.
*/
GstFlowReturn
gst_pad_push (GstPad * pad, GstBuffer * buffer)
{
GstPad *peer;
GstFlowReturn ret;
GstCaps *caps;
gboolean caps_changed;
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
GST_OBJECT_LOCK (pad);
/* FIXME: this check can go away; pad_set_blocked could be implemented with
* probes completely or probes with an extended pad block. */
while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
goto flushed;
/* we emit signals on the pad arg, the peer will have a chance to
* emit in the _chain() function */
if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
/* unlock before emitting */
GST_OBJECT_UNLOCK (pad);
/* if the signal handler returned FALSE, it means we should just drop the
* buffer */
if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
goto dropped;
GST_OBJECT_LOCK (pad);
}
if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
goto not_linked;
/* take ref to peer pad before releasing the lock */
gst_object_ref (peer);
/* Before pushing the buffer to the peer pad, ensure that caps
* are set on this pad */
caps = GST_BUFFER_CAPS (buffer);
caps_changed = caps && caps != GST_PAD_CAPS (pad);
GST_OBJECT_UNLOCK (pad);
/* we got a new datatype from the pad, it had better handle it */
if (G_UNLIKELY (caps_changed)) {
GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
goto not_negotiated;
}
ret = gst_pad_chain_unchecked (peer, buffer);
gst_object_unref (peer);
return ret;
/* ERROR recovery here */
flushed:
{
gst_buffer_unref (buffer);
GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
GST_OBJECT_UNLOCK (pad);
return ret;
}
dropped:
{
gst_buffer_unref (buffer);
GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
return GST_FLOW_OK;
}
not_linked:
{
gst_buffer_unref (buffer);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but it was not linked");
GST_OBJECT_UNLOCK (pad);
return GST_FLOW_NOT_LINKED;
}
not_negotiated:
{
gst_buffer_unref (buffer);
gst_object_unref (peer);
GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
"element pushed buffer then refused to accept the caps");
return GST_FLOW_NOT_NEGOTIATED;
}
}
/**
* gst_pad_check_pull_range:
* @pad: a sink #GstPad.
*
* Checks if a gst_pad_pull_range() can be performed on the peer
* source pad. This function is used by plugins that want to check
* if they can use random access on the peer source pad.
*
* The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
* if it needs to perform some logic to determine if pull_range is
* possible.
*
* Returns: a gboolean with the result.
*
* MT safe.
*/
gboolean
gst_pad_check_pull_range (GstPad * pad)
{
GstPad *peer;
gboolean ret;
GstPadCheckGetRangeFunction checkgetrangefunc;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
goto wrong_direction;
if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
goto not_connected;
gst_object_ref (peer);
GST_OBJECT_UNLOCK (pad);
/* see note in above function */
if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
/* FIXME, kindoff ghetto */
ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
} else {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"calling checkgetrangefunc %s of peer pad %s:%s",
GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
ret = checkgetrangefunc (peer);
}
gst_object_unref (peer);
return ret;
/* ERROR recovery here */
wrong_direction:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"checking pull range, but pad must be a sinkpad");
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
not_connected:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"checking pull range, but it was not linked");
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
}
/**
* gst_pad_get_range:
* @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
* @offset: The start offset of the buffer
* @size: The length of the buffer
* @buffer: a pointer to hold the #GstBuffer, returns #GST_FLOW_ERROR if %NULL.
*
* When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
* immediatly.
*
* Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
* description of a getrange function. If @pad has no getrange function
* installed (see gst_pad_set_getrange_function()) this function returns
* #GST_FLOW_NOT_SUPPORTED.
*
* Returns: a #GstFlowReturn from the pad.
*
* MT safe.
*/
GstFlowReturn
gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
GstBuffer ** buffer)
{
GstFlowReturn ret;
GstPadGetRangeFunction getrangefunc;
gboolean emit_signal;
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
GST_PAD_STREAM_LOCK (pad);
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
GST_OBJECT_UNLOCK (pad);
if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
goto no_function;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"calling getrangefunc %s, offset %"
G_GUINT64_FORMAT ", size %u",
GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
ret = getrangefunc (pad, offset, size, buffer);
/* can only fire the signal if we have a valid buffer */
if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
goto dropping;
}
GST_PAD_STREAM_UNLOCK (pad);
return ret;
/* ERRORS */
flushing:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pulling range, but pad was flushing");
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_WRONG_STATE;
}
no_function:
{
GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
("pullrange on pad %s:%s but it has no getrangefunction",
GST_DEBUG_PAD_NAME (pad)));
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_NOT_SUPPORTED;
}
dropping:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"Dropping data after FALSE probe return");
GST_PAD_STREAM_UNLOCK (pad);
gst_buffer_unref (*buffer);
*buffer = NULL;
return GST_FLOW_UNEXPECTED;
}
}
/**
* gst_pad_pull_range:
* @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
* @offset: The start offset of the buffer
* @size: The length of the buffer
* @buffer: a pointer to hold the #GstBuffer, returns GST_FLOW_ERROR if %NULL.
*
* Pulls a buffer from the peer pad.
*
* This function will first trigger the pad block signal if it was
* installed.
*
* When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
* function returns the result of gst_pad_get_range() on the peer pad.
* See gst_pad_get_range() for a list of return values and for the
* semantics of the arguments of this function.
*
* Returns: a #GstFlowReturn from the peer pad.
* When this function returns #GST_FLOW_OK, @buffer will contain a valid
* #GstBuffer that should be freed with gst_buffer_unref() after usage.
* @buffer may not be used or freed when any other return value than
* #GST_FLOW_OK is returned.
*
* MT safe.
*/
GstFlowReturn
gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
GstBuffer ** buffer)
{
GstPad *peer;
GstFlowReturn ret;
gboolean emit_signal;
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
GST_FLOW_ERROR);
g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
GST_OBJECT_LOCK (pad);
while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
handle_pad_block (pad);
if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
goto not_connected;
/* signal emision for the pad, peer has chance to emit when
* we call _get_range() */
emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
gst_object_ref (peer);
GST_OBJECT_UNLOCK (pad);
ret = gst_pad_get_range (peer, offset, size, buffer);
gst_object_unref (peer);
/* can only fire the signal if we have a valid buffer */
if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
goto dropping;
}
return ret;
/* ERROR recovery here */
not_connected:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pulling range, but it was not linked");
GST_OBJECT_UNLOCK (pad);
return GST_FLOW_NOT_LINKED;
}
dropping:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"Dropping data after FALSE probe return");
gst_buffer_unref (*buffer);
*buffer = NULL;
return GST_FLOW_UNEXPECTED;
}
}
/**
* 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. This function is
* mainly used by elements to send events to their peer
* elements.
*
* This function takes owership of the provided event so you should
* gst_event_ref() it if you want to reuse the event after this call.
*
* Returns: TRUE if the event was handled.
*
* MT safe.
*/
gboolean
gst_pad_push_event (GstPad * pad, GstEvent * event)
{
GstPad *peerpad;
gboolean result;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
GST_LOG_OBJECT (pad, "event:%s", GST_EVENT_TYPE_NAME (event));
GST_OBJECT_LOCK (pad);
/* Two checks to be made:
* . (un)set the FLUSHING flag for flushing events,
* . handle pad blocking */
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_FLUSH_START:
GST_PAD_SET_FLUSHING (pad);
if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
/* flush start will have set the FLUSHING flag and will then
* unlock all threads doing a GCond wait on the blocked pad. This
* will typically unblock the STREAMING thread blocked on a pad. */
GST_PAD_BLOCK_SIGNAL (pad);
goto flushed;
}
break;
case GST_EVENT_FLUSH_STOP:
GST_PAD_UNSET_FLUSHING (pad);
if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
goto flushed;
break;
default:
if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
if (GST_PAD_IS_FLUSHING (pad))
goto flushed;
while (GST_PAD_IS_BLOCKED (pad))
/* else block the event as long as the pad is blocked */
if (handle_pad_block (pad) != GST_FLOW_OK)
goto flushed;
}
break;
}
if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
GST_OBJECT_UNLOCK (pad);
if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
goto dropping;
GST_OBJECT_LOCK (pad);
}
peerpad = GST_PAD_PEER (pad);
if (peerpad == NULL)
goto not_linked;
GST_LOG_OBJECT (pad, "sending event to peerpad %" GST_PTR_FORMAT, peerpad);
gst_object_ref (peerpad);
GST_OBJECT_UNLOCK (pad);
result = gst_pad_send_event (peerpad, event);
GST_LOG_OBJECT (pad, "sent event to peerpad %" GST_PTR_FORMAT, peerpad);
gst_object_unref (peerpad);
return result;
/* ERROR handling */
dropping:
{
GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
gst_event_unref (event);
return FALSE;
}
not_linked:
{
GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
gst_event_unref (event);
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
flushed:
{
GST_DEBUG_OBJECT (pad,
"Not forwarding event since we're flushing and blocking");
gst_event_unref (event);
GST_OBJECT_UNLOCK (pad);
return TRUE;
}
}
/**
* 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.
*
* If @pad is a source pad, @event should be an upstream event. If @pad is a
* sink pad, @event should be a downstream event. For example, you would not
* send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
* Furthermore, some downstream events have to be serialized with data flow,
* like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
* the event needs to be serialized with data flow, this function will take the
* pad's stream lock while calling its event function.
*
* To find out whether an event type is upstream, downstream, or downstream and
* serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
* #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
* #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or plugin
* doesn't need to bother itself with this information; the core handles all
* necessary locks and checks.
*
* This function takes owership of the provided event so you should
* gst_event_ref() it if you want to reuse the event after this call.
*
* Returns: TRUE if the event was handled.
*/
gboolean
gst_pad_send_event (GstPad * pad, GstEvent * event)
{
gboolean result = FALSE;
GstPadEventFunction eventfunc;
gboolean serialized, need_unlock = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
GST_OBJECT_LOCK (pad);
if (GST_PAD_IS_SINK (pad)) {
if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
goto wrong_direction;
serialized = GST_EVENT_IS_SERIALIZED (event);
} else if (GST_PAD_IS_SRC (pad)) {
if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
goto wrong_direction;
/* events on srcpad never are serialized */
serialized = FALSE;
} else
goto unknown_direction;
if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
GST_EVENT_SRC (event) = gst_object_ref (pad);
}
/* pad signals */
if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
GST_OBJECT_UNLOCK (pad);
if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
goto dropping;
GST_OBJECT_LOCK (pad);
}
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_FLUSH_START:
GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
"have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
/* can't even accept a flush begin event when flushing */
if (GST_PAD_IS_FLUSHING (pad))
goto flushing;
GST_PAD_SET_FLUSHING (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
break;
case GST_EVENT_FLUSH_STOP:
GST_PAD_UNSET_FLUSHING (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
GST_OBJECT_UNLOCK (pad);
/* grab stream lock */
GST_PAD_STREAM_LOCK (pad);
need_unlock = TRUE;
GST_OBJECT_LOCK (pad);
break;
default:
GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
GST_EVENT_TYPE_NAME (event));
/* make this a little faster, no point in grabbing the lock
* if the pad is allready flushing. */
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
if (serialized) {
/* lock order: STREAM_LOCK, LOCK */
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_LOCK (pad);
need_unlock = TRUE;
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
}
break;
}
if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
goto no_function;
GST_OBJECT_UNLOCK (pad);
result = eventfunc (pad, event);
if (need_unlock)
GST_PAD_STREAM_UNLOCK (pad);
return result;
/* ERROR handling */
wrong_direction:
{
g_warning ("pad %s:%s sending %s event in wrong direction",
GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
GST_OBJECT_UNLOCK (pad);
gst_event_unref (event);
return FALSE;
}
unknown_direction:
{
g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
GST_OBJECT_UNLOCK (pad);
gst_event_unref (event);
return FALSE;
}
no_function:
{
g_warning ("pad %s:%s has no event handler, file a bug.",
GST_DEBUG_PAD_NAME (pad));
GST_OBJECT_UNLOCK (pad);
gst_event_unref (event);
return FALSE;
}
flushing:
{
GST_OBJECT_UNLOCK (pad);
if (need_unlock)
GST_PAD_STREAM_UNLOCK (pad);
GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
"Received event on flushing pad. Discarding");
gst_event_unref (event);
return FALSE;
}
dropping:
{
GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
gst_event_unref (event);
return FALSE;
}
}
/**
* 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.
* No locking is performed in this function.
*/
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.
* No locking is performed in this function.
*
* Returns: a #gpointer to the private data.
*/
gpointer
gst_pad_get_element_private (GstPad * pad)
{
return pad->element_private;
}
/**
* gst_pad_start_task:
* @pad: the #GstPad to start the task of
* @func: the task function to call
* @data: data passed to the task function
*
* Starts a task that repeadedly calls @func with @data. This function
* is nostly used in the pad activation function to start the
* dataflow. This function will automatically acquire the STREAM_LOCK of
* the pad before calling @func.
*
* Returns: a TRUE if the task could be started.
*/
gboolean
gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
{
GstTask *task;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (func != NULL, FALSE);
GST_DEBUG_OBJECT (pad, "start task");
GST_OBJECT_LOCK (pad);
task = GST_PAD_TASK (pad);
if (task == NULL) {
task = gst_task_create (func, data);
gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
GST_PAD_TASK (pad) = task;
GST_DEBUG_OBJECT (pad, "created task");
}
gst_task_start (task);
GST_OBJECT_UNLOCK (pad);
return TRUE;
}
/**
* gst_pad_pause_task:
* @pad: the #GstPad to pause the task of
*
* Pause the task of @pad. This function will also make sure that the
* function executed by the task will effectively stop.
*
* Returns: a TRUE if the task could be paused or FALSE when the pad
* has no task.
*/
gboolean
gst_pad_pause_task (GstPad * pad)
{
GstTask *task;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_DEBUG_OBJECT (pad, "pause task");
GST_OBJECT_LOCK (pad);
task = GST_PAD_TASK (pad);
if (task == NULL)
goto no_task;
gst_task_pause (task);
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_LOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
return TRUE;
no_task:
{
GST_DEBUG_OBJECT (pad, "pad has no task");
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
}
/**
* gst_pad_stop_task:
* @pad: the #GstPad to stop the task of
*
* Stop the task of @pad. This function will also make sure that the
* function executed by the task will effectively stop if not called
* from the GstTaskFunction.
*
* This function will deadlock if called from the GstTaskFunction of
* the task. Use gst_task_pause() instead.
*
* Regardless of whether the pad has a task, the stream lock is acquired and
* released so as to ensure that streaming through this pad has finished.
*
* Returns: a TRUE if the task could be stopped or FALSE on error.
*/
gboolean
gst_pad_stop_task (GstPad * pad)
{
GstTask *task;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_DEBUG_OBJECT (pad, "stop task");
GST_OBJECT_LOCK (pad);
task = GST_PAD_TASK (pad);
if (task == NULL)
goto no_task;
GST_PAD_TASK (pad) = NULL;
gst_task_stop (task);
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_LOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
if (!gst_task_join (task))
goto join_failed;
gst_object_unref (task);
return TRUE;
no_task:
{
GST_DEBUG_OBJECT (pad, "no task");
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_LOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
/* this is not an error */
return TRUE;
}
join_failed:
{
/* this is bad, possibly the application tried to join the task from
* the task's thread. We install the task again so that it will be stopped
* again from the right thread next time hopefully. */
GST_OBJECT_LOCK (pad);
GST_DEBUG_OBJECT (pad, "join failed");
/* we can only install this task if there was no other task */
if (GST_PAD_TASK (pad) == NULL)
GST_PAD_TASK (pad) = task;
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
}
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