gstreamer/gst/gstpad.c
2011-09-28 18:44:12 +02:00

4934 lines
134 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstpad.c: Pads for linking elements together
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* 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,
/* FILL ME */
LAST_SIGNAL
};
enum
{
PAD_PROP_0,
PAD_PROP_CAPS,
PAD_PROP_DIRECTION,
PAD_PROP_TEMPLATE,
/* FILL ME */
};
#define GST_PAD_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PAD, GstPadPrivate))
/* we have a pending and an active event on the pad. On source pads only the
* active event is used. On sinkpads, events are copied to the pending entry and
* moved to the active event when the eventfunc returned TRUE. */
typedef struct
{
GstEvent *pending;
GstEvent *event;
} PadEvent;
struct _GstPadPrivate
{
PadEvent events[GST_EVENT_MAX_STICKY];
gint using;
gint probe_cookie;
};
typedef struct
{
GHook hook;
guint cookie;
} GstProbe;
#define PROBE_COOKIE(h) (((GstProbe *)(h))->cookie)
typedef struct
{
GstPad *pad;
GstProbeType mask;
gpointer type_data;
GstProbeReturn ret;
gboolean pass;
guint cookie;
} ProbeMarshall;
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 GstCaps *gst_pad_get_caps_unlocked (GstPad * pad, GstCaps * filter);
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);
static void gst_pad_fixate_caps_default (GstPad * pad, GstCaps * caps);
static GstFlowReturn gst_pad_chain_list_default (GstPad * pad,
GstBufferList * list);
static GstObjectClass *parent_class = NULL;
static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
static GParamSpec *pspec_caps = NULL;
/* quarks for probe signals */
static GQuark buffer_quark;
static GQuark buffer_list_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}
};
/**
* 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.
*/
const gchar *
gst_flow_get_name (GstFlowReturn ret)
{
gint i;
ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
for (i = 0; i < G_N_ELEMENTS (flow_quarks); 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; i < G_N_ELEMENTS (flow_quarks); i++) {
if (ret == flow_quarks[i].ret)
return flow_quarks[i].quark;
}
return 0;
}
#define _do_init \
{ \
gint i; \
\
buffer_quark = g_quark_from_static_string ("buffer"); \
buffer_list_quark = g_quark_from_static_string ("bufferlist"); \
event_quark = g_quark_from_static_string ("event"); \
\
for (i = 0; i < G_N_ELEMENTS (flow_quarks); 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"); \
}
G_DEFINE_TYPE_WITH_CODE (GstPad, gst_pad, GST_TYPE_OBJECT, _do_init);
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);
g_type_class_add_private (klass, sizeof (GstPadPrivate));
parent_class = g_type_class_peek_parent (klass);
gobject_class->dispose = gst_pad_dispose;
gobject_class->finalize = gst_pad_finalize;
gobject_class->set_property = gst_pad_set_property;
gobject_class->get_property = 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);
pspec_caps = g_param_spec_boxed ("caps", "Caps",
"The capabilities of the pad", GST_TYPE_CAPS,
G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
g_object_class_install_property (gobject_class, PAD_PROP_CAPS, pspec_caps);
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 | G_PARAM_STATIC_STRINGS));
/* 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 | G_PARAM_STATIC_STRINGS));
gstobject_class->path_string_separator = ".";
/* Register common function pointer descriptions */
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_activate_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_event_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_query_types_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_query_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_iterate_internal_links_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_acceptcaps_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_chain_list_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_fixate_caps_default);
}
static void
gst_pad_init (GstPad * pad)
{
pad->priv = GST_PAD_GET_PRIVATE (pad);
GST_PAD_DIRECTION (pad) = GST_PAD_UNKNOWN;
GST_PAD_ACTIVATEFUNC (pad) = gst_pad_activate_default;
GST_PAD_EVENTFUNC (pad) = gst_pad_event_default;
GST_PAD_QUERYTYPEFUNC (pad) = gst_pad_get_query_types_default;
GST_PAD_QUERYFUNC (pad) = gst_pad_query_default;
GST_PAD_ITERINTLINKFUNC (pad) = gst_pad_iterate_internal_links_default;
GST_PAD_ACCEPTCAPSFUNC (pad) = gst_pad_acceptcaps_default;
GST_PAD_FIXATECAPSFUNC (pad) = gst_pad_fixate_caps_default;
GST_PAD_CHAINLISTFUNC (pad) = gst_pad_chain_list_default;
GST_PAD_SET_FLUSHING (pad);
g_static_rec_mutex_init (&pad->stream_rec_lock);
pad->block_cond = g_cond_new ();
g_hook_list_init (&pad->probes, sizeof (GstProbe));
}
/* called when setting the pad inactive. It removes all sticky events from
* the pad */
static void
clear_events (PadEvent events[])
{
guint i;
for (i = 0; i < GST_EVENT_MAX_STICKY; i++) {
gst_event_replace (&events[i].event, NULL);
gst_event_replace (&events[i].pending, NULL);
}
}
/* The sticky event with @idx from the srcpad is copied to the
* pending event on the sinkpad (when different).
* This function applies the pad offsets in case of segment events.
* This will make sure that we send the event to the sinkpad event
* function when the next buffer of event arrives.
* Should be called with the OBJECT lock of both pads.
* This function returns TRUE when there is a pending event on the
* sinkpad */
static gboolean
replace_event (GstPad * srcpad, GstPad * sinkpad, guint idx)
{
PadEvent *srcev, *sinkev;
GstEvent *event;
gboolean pending = FALSE;
srcev = &srcpad->priv->events[idx];
if ((event = srcev->event)) {
sinkev = &sinkpad->priv->events[idx];
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_SEGMENT:
{
GstSegment segment;
gint64 offset;
offset = srcpad->offset + sinkpad->offset;
if (offset != 0) {
gst_event_copy_segment (event, &segment);
/* adjust the base time. FIXME, check negative times, try to tweak the
* start to do clipping on negative times */
segment.base += offset;
/* make a new event from the updated segment */
event = gst_event_new_segment (&segment);
}
break;
}
default:
break;
}
if (sinkev->event != event) {
/* put in the pending entry when different */
gst_event_replace (&sinkev->pending, event);
pending = TRUE;
}
}
return pending;
}
static void
prepare_event_update (GstPad * srcpad, GstPad * sinkpad)
{
gboolean pending;
gint i;
/* make sure we push the events from the source to this new peer, for this we
* copy the events on the sinkpad and mark EVENTS_PENDING */
pending = FALSE;
for (i = 0; i < GST_EVENT_MAX_STICKY; i++)
pending |= replace_event (srcpad, sinkpad, i);
/* we had some new pending events, set our flag */
if (pending)
GST_OBJECT_FLAG_SET (sinkpad, GST_PAD_NEED_EVENTS);
}
/* should be called with the OBJECT_LOCK */
static GstCaps *
get_pad_caps (GstPad * pad)
{
GstCaps *caps = NULL;
GstEvent *event;
guint idx;
idx = GST_EVENT_STICKY_IDX_TYPE (GST_EVENT_CAPS);
/* we can only use the caps when we have successfully send the caps
* event to the event function and is thus in the active entry */
if ((event = pad->priv->events[idx].event))
gst_event_parse_caps (event, &caps);
return caps;
}
static void
gst_pad_dispose (GObject * object)
{
GstPad *pad = GST_PAD_CAST (object);
GstPad *peer;
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pad, "dispose");
/* unlink the peer pad */
if ((peer = gst_pad_get_peer (pad))) {
/* window for MT unsafeness, someone else could unlink here
* and then we call unlink with wrong pads. The unlink
* function would catch this and safely return failed. */
if (GST_PAD_IS_SRC (pad))
gst_pad_unlink (pad, peer);
else
gst_pad_unlink (peer, pad);
gst_object_unref (peer);
}
gst_pad_set_pad_template (pad, NULL);
clear_events (pad->priv->events);
g_hook_list_clear (&pad->probes);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_pad_finalize (GObject * object)
{
GstPad *pad = GST_PAD_CAST (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);
}
g_static_rec_mutex_free (&pad->stream_rec_lock);
g_cond_free (pad->block_cond);
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) = (GstPadDirection) 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, get_pad_caps (GST_PAD_CAST (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: (transfer full): 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: (transfer full): 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: (transfer full): 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);
result = GST_PAD_DIRECTION (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");
GST_PAD_SET_FLUSHING (pad);
GST_PAD_ACTIVATE_MODE (pad) = new_mode;
/* unlock blocked pads so element can resume and stop */
GST_PAD_BLOCK_BROADCAST (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);
GST_DEBUG_OBJECT (pad, "stopped streaming");
GST_OBJECT_LOCK (pad);
clear_events (pad->priv->events);
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:
GST_DEBUG_OBJECT (pad, "activating pad from push");
ret = TRUE;
break;
case GST_ACTIVATE_PULL:
GST_DEBUG_OBJECT (pad, "activating pad from pull");
ret = TRUE;
break;
case GST_ACTIVATE_NONE:
GST_DEBUG_OBJECT (pad, "activating pad from none");
ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
break;
default:
GST_DEBUG_OBJECT (pad, "unknown activation mode!");
break;
}
} else {
switch (old) {
case GST_ACTIVATE_PUSH:
GST_DEBUG_OBJECT (pad, "deactivating pad from push");
ret = gst_pad_activate_push (pad, FALSE);
break;
case GST_ACTIVATE_PULL:
GST_DEBUG_OBJECT (pad, "deactivating pad from pull");
ret = gst_pad_activate_pull (pad, FALSE);
break;
case GST_ACTIVATE_NONE:
GST_DEBUG_OBJECT (pad, "deactivating pad from none");
ret = TRUE;
break;
default:
GST_DEBUG_OBJECT (pad, "unknown activation mode!");
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_OBJECT (pad, "Failed to activate pad");
}
GST_OBJECT_UNLOCK (pad);
} else {
if (!active) {
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_NEED_RECONFIGURE);
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:
GST_DEBUG_OBJECT (pad, "activating pad from pull, was ok");
goto was_ok;
case GST_ACTIVATE_PUSH:
GST_DEBUG_OBJECT (pad,
"activating pad from push, deactivate push first");
/* 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:
GST_DEBUG_OBJECT (pad, "activating pad from none");
break;
}
} else {
switch (old) {
case GST_ACTIVATE_NONE:
GST_DEBUG_OBJECT (pad, "deactivating pad from none, was ok");
goto was_ok;
case GST_ACTIVATE_PUSH:
GST_DEBUG_OBJECT (pad, "deactivating pad from push, weird");
/* 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:
GST_DEBUG_OBJECT (pad, "deactivating pad from pull");
break;
}
}
if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
if ((peer = gst_pad_get_peer (pad))) {
GST_DEBUG_OBJECT (pad, "calling peer");
if (G_UNLIKELY (!gst_pad_activate_pull (peer, active)))
goto peer_failed;
gst_object_unref (peer);
} else {
/* there is no peer, this is only fatal when we activate. When we
* deactivate, we must assume the application has unlinked the peer and
* will deactivate it eventually. */
if (active)
goto not_linked;
else
GST_DEBUG_OBJECT (pad, "deactivating unlinked pad");
}
} 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;
}
not_linked:
{
GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "can't activate unlinked sink "
"pad in pull mode");
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:
GST_DEBUG_OBJECT (pad, "activating pad from push, was ok");
goto was_ok;
case GST_ACTIVATE_PULL:
GST_DEBUG_OBJECT (pad,
"activating pad from push, deactivating pull first");
/* 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:
GST_DEBUG_OBJECT (pad, "activating pad from none");
break;
}
} else {
switch (old) {
case GST_ACTIVATE_NONE:
GST_DEBUG_OBJECT (pad, "deactivating pad from none, was ok");
goto was_ok;
case GST_ACTIVATE_PULL:
GST_DEBUG_OBJECT (pad, "deactivating pad from pull, weird");
/* 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:
GST_DEBUG_OBJECT (pad, "deactivating pad from 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_IS_ACTIVE (pad);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_add_probe:
* @pad: the #GstPad to add the probe to
* @mask: the probe mask
* @callback: #GstPadProbeCallback that will be called with notifications of
* the pad state
* @user_data: (closure): user data passed to the callback
* @destroy_data: #GDestroyNotify for user_data
*
* Be notified of different states of pads. The provided callback is called for
* every state that matches @mask.
*
* <note>
* Pad probe handlers are only called for source pads in push mode
* and sink pads in pull mode.
* </note>
*
* Returns: an id or 0 on error. The id can be used to remove the probe with
* gst_pad_remove_probe().
*
* MT safe.
*/
gulong
gst_pad_add_probe (GstPad * pad, GstProbeType mask,
GstPadProbeCallback callback, gpointer user_data,
GDestroyNotify destroy_data)
{
GHook *hook;
gulong res;
g_return_val_if_fail (GST_IS_PAD (pad), 0);
g_return_val_if_fail (mask != 0, 0);
GST_OBJECT_LOCK (pad);
/* make a new probe */
hook = g_hook_alloc (&pad->probes);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "adding probe for mask 0x%08x",
mask);
/* when no contraints are given for the types, assume all types are
* acceptable */
if ((mask & GST_PROBE_TYPE_DATA) == 0)
mask |= GST_PROBE_TYPE_DATA;
if ((mask & GST_PROBE_TYPE_SCHEDULING) == 0)
mask |= GST_PROBE_TYPE_SCHEDULING;
/* store our flags and other fields */
hook->flags |= (mask << G_HOOK_FLAG_USER_SHIFT);
hook->func = callback;
hook->data = user_data;
hook->destroy = destroy_data;
PROBE_COOKIE (hook) = 0;
/* incremenent cookie so that the new hook get's called */
pad->priv->probe_cookie++;
/* add the probe */
g_hook_prepend (&pad->probes, hook);
pad->num_probes++;
/* get the id of the hook, we return this and it can be used to remove the
* probe later */
res = hook->hook_id;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got probe id %lu", res);
if (mask & GST_PROBE_TYPE_BLOCKING) {
/* we have a block probe */
pad->num_blocked++;
GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "added blocking probe, "
"now %d blocking probes", pad->num_blocked);
}
/* call the callback if we need to be called for idle callbacks */
if ((mask & GST_PROBE_TYPE_IDLE) && (callback != NULL)) {
if (pad->priv->using > 0) {
/* the pad is in use, we can't signal the idle callback yet. Since we set the
* flag above, the last thread to leave the push will do the callback. New
* threads going into the push will block. */
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pad is in use, delay idle callback");
GST_OBJECT_UNLOCK (pad);
} else {
/* the pad is idle now, we can signal the idle callback now */
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pad is idle, trigger idle callback");
GST_OBJECT_UNLOCK (pad);
callback (pad, GST_PROBE_TYPE_IDLE, NULL, user_data);
}
} else {
GST_OBJECT_UNLOCK (pad);
}
return res;
}
static void
cleanup_hook (GstPad * pad, GHook * hook)
{
GstProbeType type;
type = (hook->flags) >> G_HOOK_FLAG_USER_SHIFT;
if (type & GST_PROBE_TYPE_BLOCKING) {
/* unblock when we remove the last blocking probe */
pad->num_blocked--;
GST_DEBUG_OBJECT (pad, "remove blocking probe, now %d left",
pad->num_blocked);
if (pad->num_blocked == 0) {
GST_DEBUG_OBJECT (pad, "last blocking probe removed, unblocking");
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
GST_PAD_BLOCK_BROADCAST (pad);
}
}
g_hook_destroy_link (&pad->probes, hook);
pad->num_probes--;
}
/**
* gst_pad_remove_probe:
* @pad: the #GstPad with the probe
* @id: the probe id to remove
*
* Remove the probe with @id from @pad.
*
* MT safe.
*/
void
gst_pad_remove_probe (GstPad * pad, gulong id)
{
GHook *hook;
g_return_if_fail (GST_IS_PAD (pad));
GST_OBJECT_LOCK (pad);
hook = g_hook_get (&pad->probes, id);
if (hook == NULL)
goto not_found;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "removing hook %ld",
hook->hook_id);
cleanup_hook (pad, hook);
GST_OBJECT_UNLOCK (pad);
return;
not_found:
{
GST_OBJECT_UNLOCK (pad);
g_warning ("%s: pad `%p' has no probe with id `%lu'", G_STRLOC, pad, id);
return;
}
}
/**
* 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 blocking at this point (see gst_pad_is_blocking()).
*
* 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_is_blocking:
* @pad: the #GstPad to query
*
* Checks if the pad is blocking or not. This is a guaranteed state
* of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
*
* Returns: TRUE if the pad is blocking.
*
* MT safe.
*
* Since: 0.10.11
*/
gboolean
gst_pad_is_blocking (GstPad * pad)
{
gboolean result = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), result);
GST_OBJECT_LOCK (pad);
/* the blocking flag is only valid if the pad is not flushing */
result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKING) &&
!GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLUSHING);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_check_reconfigure:
* @pad: the #GstPad to check
*
* Check and clear the #GST_PAD_NEED_RECONFIGURE flag on @pad and return %TRUE
* if the flag was set.
*
* Returns: %TRUE is the GST_PAD_NEED_RECONFIGURE flag was set on @pad.
*/
gboolean
gst_pad_check_reconfigure (GstPad * pad)
{
gboolean reconfigure;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
reconfigure = GST_PAD_NEEDS_RECONFIGURE (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_NEED_RECONFIGURE);
GST_OBJECT_UNLOCK (pad);
return reconfigure;
}
/**
* gst_pad_mark_reconfigure:
* @pad: the #GstPad to mark
*
* Mark a pad for needing reconfiguration. The next call to
* gst_pad_check_reconfigure() will return %TRUE after this call.
*/
void
gst_pad_mark_reconfigure (GstPad * pad)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_SET (pad, GST_PAD_NEED_RECONFIGURE);
GST_OBJECT_UNLOCK (pad);
}
/**
* 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_IS_SINK (pad));
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_chain_list_function:
* @pad: a sink #GstPad.
* @chainlist: the #GstPadChainListFunction to set.
*
* Sets the given chain list function for the pad. The chainlist function is
* called to process a #GstBufferList input buffer list. See
* #GstPadChainListFunction for more details.
*
* Since: 0.10.24
*/
void
gst_pad_set_chain_list_function (GstPad * pad,
GstPadChainListFunction chainlist)
{
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_IS_SINK (pad));
GST_PAD_CHAINLISTFUNC (pad) = chainlist;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainlistfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (chainlist));
}
/**
* 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_IS_SRC (pad));
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_event_function:
* @pad: a #GstPad of either direction.
* @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: (transfer none) (array zero-terminated=1): 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)
{
GstPad *peer;
if ((peer = gst_pad_get_peer (pad))) {
*data = gst_pad_get_query_types (peer);
gst_object_unref (peer);
}
return TRUE;
}
/**
* gst_pad_get_query_types_default:
* @pad: a #GstPad.
*
* Invoke the default query types function on the pad. This function will get
* the supported query type from the peer of an internally linked pad of @pad.
*
* Returns: (transfer none) (array zero-terminated=1): a 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_forward (pad, (GstPadForwardFunction)
gst_pad_get_query_types_dispatcher, &result);
return result;
}
/**
* gst_pad_set_iterate_internal_links_function:
* @pad: a #GstPad of either direction.
* @iterintlink: the #GstPadIterIntLinkFunction to set.
*
* Sets the given internal link iterator function for the pad.
*
* Since: 0.10.21
*/
void
gst_pad_set_iterate_internal_links_function (GstPad * pad,
GstPadIterIntLinkFunction iterintlink)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_PAD_ITERINTLINKFUNC (pad) = iterintlink;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link iterator set to %s",
GST_DEBUG_FUNCPTR_NAME (iterintlink));
}
/**
* 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_unlink:
* @srcpad: the source #GstPad to unlink.
* @sinkpad: the sink #GstPad to unlink.
*
* Unlinks the source pad from the sink pad. Will emit the #GstPad::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)
{
gboolean result = FALSE;
GstElement *parent = NULL;
gint i;
g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), FALSE);
g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
g_return_val_if_fail (GST_PAD_IS_SINK (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);
/* We need to notify the parent before taking any pad locks as the bin in
* question might be waiting for a lock on the pad while holding its lock
* that our message will try to take. */
if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
if (GST_IS_ELEMENT (parent)) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, TRUE));
} else {
gst_object_unref (parent);
parent = NULL;
}
}
GST_OBJECT_LOCK (srcpad);
GST_OBJECT_LOCK (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;
/* clear pending caps if any */
for (i = 0; i < GST_EVENT_MAX_STICKY; i++)
gst_event_replace (&sinkpad->priv->events[i].pending, 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 (srcpad, gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
g_signal_emit (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));
result = TRUE;
done:
if (parent != NULL) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, FALSE));
gst_object_unref (parent);
}
return result;
/* ERRORS */
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);
goto done;
}
}
/**
* 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,
GstPadLinkCheck flags)
{
GstCaps *srccaps = NULL;
GstCaps *sinkcaps = NULL;
gboolean compatible = FALSE;
if (!(flags & (GST_PAD_LINK_CHECK_CAPS | GST_PAD_LINK_CHECK_TEMPLATE_CAPS)))
return TRUE;
/* Doing the expensive caps checking takes priority over only checking the template caps */
if (flags & GST_PAD_LINK_CHECK_CAPS) {
srccaps = gst_pad_get_caps_unlocked (src, NULL);
sinkcaps = gst_pad_get_caps_unlocked (sink, NULL);
} else {
/* If one of the two pads doesn't have a template, consider the intersection
* as valid.*/
if (G_UNLIKELY ((GST_PAD_PAD_TEMPLATE (src) == NULL)
|| (GST_PAD_PAD_TEMPLATE (sink) == NULL))) {
compatible = TRUE;
goto done;
}
srccaps = gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (src)));
sinkcaps =
gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (sink)));
}
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, src, "src caps %" GST_PTR_FORMAT,
srccaps);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, sink, "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 (G_UNLIKELY (srccaps == NULL || sinkcaps == NULL)) {
if (srccaps)
gst_caps_unref (srccaps);
if (sinkcaps)
gst_caps_unref (sinkcaps);
goto done;
}
compatible = gst_caps_can_intersect (srccaps, sinkcaps);
gst_caps_unref (srccaps);
gst_caps_unref (sinkcaps);
done:
GST_CAT_DEBUG (GST_CAT_CAPS, "caps are %scompatible",
(compatible ? "" : "not"));
return compatible;
}
/* 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;
psrc = GST_OBJECT_PARENT (src);
psink = GST_OBJECT_PARENT (sink);
/* if one of the pads has no parent, we allow the link */
if (G_UNLIKELY (psrc == NULL || psink == NULL))
goto no_parent;
/* only care about parents that are elements */
if (G_UNLIKELY (!GST_IS_ELEMENT (psrc) || !GST_IS_ELEMENT (psink)))
goto no_element_parent;
/* 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. We can not lock
* the parent because we hold on the child (pad) and the locking order is
* parent >> child. */
psrc = GST_OBJECT_PARENT (psrc);
psink = GST_OBJECT_PARENT (psink);
/* if they have grandparents but they are not the same */
if (G_UNLIKELY (psrc != psink))
goto wrong_grandparents;
return TRUE;
/* ERRORS */
no_parent:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"one of the pads has no parent %" GST_PTR_FORMAT " and %"
GST_PTR_FORMAT, psrc, psink);
return TRUE;
}
no_element_parent:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"one of the pads has no element parent %" GST_PTR_FORMAT " and %"
GST_PTR_FORMAT, psrc, psink);
return TRUE;
}
same_parents:
{
GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
psrc);
return FALSE;
}
wrong_grandparents:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"pads have different grandparents %" GST_PTR_FORMAT " and %"
GST_PTR_FORMAT, psrc, psink);
return FALSE;
}
}
/* 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, GstPadLinkCheck flags)
{
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_PEER (srcpad) != NULL))
goto src_was_linked;
GST_OBJECT_LOCK (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 ((flags & GST_PAD_LINK_CHECK_HIERARCHY)
&& !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, flags))
goto no_format;
/* FIXME check pad scheduling for non-empty intersection */
return GST_PAD_LINK_OK;
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;
}
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_can_link:
* @srcpad: the source #GstPad.
* @sinkpad: the sink #GstPad.
*
* Checks if the source pad and the sink pad are compatible so they can be
* linked.
*
* Returns: TRUE if the pads can be linked.
*/
gboolean
gst_pad_can_link (GstPad * srcpad, GstPad * sinkpad)
{
GstPadLinkReturn result;
/* generic checks */
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_PADS, "check if %s:%s can link with %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
/* gst_pad_link_prepare does everything for us, we only release the locks
* on the pads that it gets us. If this function returns !OK the locks are not
* taken anymore. */
result = gst_pad_link_prepare (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
if (result != GST_PAD_LINK_OK)
goto done;
GST_OBJECT_UNLOCK (srcpad);
GST_OBJECT_UNLOCK (sinkpad);
done:
return result == GST_PAD_LINK_OK;
}
/**
* gst_pad_link_full:
* @srcpad: the source #GstPad to link.
* @sinkpad: the sink #GstPad to link.
* @flags: the checks to validate when linking
*
* Links the source pad and the sink pad.
*
* This variant of #gst_pad_link provides a more granular control on the
* checks being done when linking. While providing some considerable speedups
* the caller of this method must be aware that wrong usage of those flags
* can cause severe issues. Refer to the documentation of #GstPadLinkCheck
* for more information.
*
* MT Safe.
*
* Returns: A result code indicating if the connection worked or
* what went wrong.
*
* Since: 0.10.30
*/
GstPadLinkReturn
gst_pad_link_full (GstPad * srcpad, GstPad * sinkpad, GstPadLinkCheck flags)
{
GstPadLinkReturn result;
GstElement *parent;
GstPadLinkFunction srcfunc, sinkfunc;
g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), GST_PAD_LINK_WRONG_DIRECTION);
g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad),
GST_PAD_LINK_WRONG_DIRECTION);
/* Notify the parent early. See gst_pad_unlink for details. */
if (G_LIKELY ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad))))) {
if (G_LIKELY (GST_IS_ELEMENT (parent))) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, TRUE));
} else {
gst_object_unref (parent);
parent = NULL;
}
}
/* prepare will also lock the two pads */
result = gst_pad_link_prepare (srcpad, sinkpad, flags);
if (G_UNLIKELY (result != GST_PAD_LINK_OK))
goto done;
/* must set peers before calling the link function */
GST_PAD_PEER (srcpad) = sinkpad;
GST_PAD_PEER (sinkpad) = srcpad;
/* make sure we update events */
prepare_event_update (srcpad, sinkpad);
/* get the link functions */
srcfunc = GST_PAD_LINKFUNC (srcpad);
sinkfunc = GST_PAD_LINKFUNC (sinkpad);
if (G_UNLIKELY (srcfunc || sinkfunc)) {
/* custom link functions, execute them */
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
if (srcfunc) {
/* this one will call the peer link function */
result = srcfunc (srcpad, sinkpad);
} else if (sinkfunc) {
/* if no source link function, we need to call the sink link
* function ourselves. */
result = sinkfunc (sinkpad, srcpad);
}
GST_OBJECT_LOCK (srcpad);
GST_OBJECT_LOCK (sinkpad);
/* we released the lock, check if the same pads are linked still */
if (GST_PAD_PEER (srcpad) != sinkpad || GST_PAD_PEER (sinkpad) != srcpad)
goto concurrent_link;
if (G_UNLIKELY (result != GST_PAD_LINK_OK))
goto link_failed;
}
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 (srcpad, gst_pad_signals[PAD_LINKED], 0, sinkpad);
g_signal_emit (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));
gst_pad_send_event (srcpad, gst_event_new_reconfigure ());
done:
if (G_LIKELY (parent)) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, FALSE));
gst_object_unref (parent);
}
return result;
/* ERRORS */
concurrent_link:
{
GST_CAT_INFO (GST_CAT_PADS, "concurrent link between %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
/* The other link operation succeeded first */
result = GST_PAD_LINK_WAS_LINKED;
goto done;
}
link_failed:
{
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);
goto done;
}
}
/**
* 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)
{
return gst_pad_link_full (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
}
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: (transfer full): the #GstPadTemplate from which this pad was
* instantiated, or %NULL if this pad has no template. Unref after
* usage.
*/
GstPadTemplate *
gst_pad_get_pad_template (GstPad * pad)
{
GstPadTemplate *templ;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
templ = GST_PAD_PAD_TEMPLATE (pad);
return (templ ? gst_object_ref (templ) : NULL);
}
static GstCaps *
caps_with_getcaps (GstPad * pad, GstCaps * filter)
{
GstCaps *result;
if (GST_PAD_GETCAPSFUNC (pad) == NULL)
return NULL;
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"dispatching to pad getcaps function with "
"filter %" GST_PTR_FORMAT, filter);
GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
GST_OBJECT_UNLOCK (pad);
result = GST_PAD_GETCAPSFUNC (pad) (pad, filter);
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
if (G_UNLIKELY (result == NULL))
goto null_caps;
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 which 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;
}
}
if (filter) {
if (!gst_caps_is_subset (result, filter)) {
GstCaps *temp;
GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
"pad returned caps %" GST_PTR_FORMAT
" which are not a real subset of the filter caps %"
GST_PTR_FORMAT, result, filter);
g_warning ("pad %s:%s returned caps which are not a real "
"subset of the filter caps", GST_DEBUG_PAD_NAME (pad));
/* FIXME: Order? But shouldn't happen anyway... */
temp = gst_caps_intersect_full (filter, result, GST_CAPS_INTERSECT_FIRST);
gst_caps_unref (result);
result = temp;
}
}
#endif
return result;
/* ERRORS */
null_caps:
{
g_critical ("pad %s:%s returned NULL caps from getcaps function",
GST_DEBUG_PAD_NAME (pad));
return NULL;
}
}
/* 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 * filter)
{
GstCaps *result = NULL;
GstPadTemplate *templ;
gboolean fixed_caps;
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
fixed_caps = GST_PAD_IS_FIXED_CAPS (pad);
if (fixed_caps) {
/* fixed caps, try the negotiated caps first */
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "fixed pad caps: trying pad caps");
if ((result = get_pad_caps (pad)))
goto filter_done;
}
/* try the getcaps function next */
if ((result = caps_with_getcaps (pad, filter)))
goto done;
if ((templ = GST_PAD_PAD_TEMPLATE (pad))) {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "trying pad template caps");
if ((result = GST_PAD_TEMPLATE_CAPS (templ)))
goto filter_done;
}
if (!fixed_caps) {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"non-fixed pad caps: trying pad caps");
/* non fixed caps, try the negotiated caps */
if ((result = get_pad_caps (pad)))
goto filter_done;
}
/* this almost never happens */
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
result = gst_caps_new_empty ();
goto done;
filter_done:
/* run the filter on the result */
if (filter) {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"using caps %p %" GST_PTR_FORMAT " with filter %p %"
GST_PTR_FORMAT, result, result, filter, filter);
result = gst_caps_intersect_full (filter, result, GST_CAPS_INTERSECT_FIRST);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "result %p %" GST_PTR_FORMAT,
result, result);
} else {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"using caps %p %" GST_PTR_FORMAT, result, result);
result = gst_caps_ref (result);
}
done:
return result;
}
/**
* gst_pad_has_current_caps:
* @pad: a #GstPad to check
*
* Check if @pad has caps set on it with a #GST_EVENT_CAPS event.
*
* Returns: TRUE when @pad has caps associated with it.
*/
gboolean
gst_pad_has_current_caps (GstPad * pad)
{
gboolean result;
GstCaps *caps;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
caps = get_pad_caps (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"check current pad caps %" GST_PTR_FORMAT, caps);
result = (caps != NULL);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_get_current_caps:
* @pad: a #GstPad to get the current capabilities of.
*
* Gets the capabilities currently configured on @pad with the last
* #GST_EVENT_CAPS event.
*
* Returns: the current caps of the pad with incremented ref-count.
*/
GstCaps *
gst_pad_get_current_caps (GstPad * pad)
{
GstCaps *result;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
if ((result = get_pad_caps (pad)))
gst_caps_ref (result);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"get current pad caps %" GST_PTR_FORMAT, result);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_get_caps:
* @pad: a #GstPad to get the capabilities of.
* @filter: suggested #GstCaps.
*
* 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_get_current_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.
*
* When called on sinkpads @filter contains the caps that
* upstream could produce in the order preferred by upstream. When
* called on srcpads @filter contains the caps accepted by
* downstream in the preffered order. @filter might be %NULL but
* if it is not %NULL the returned caps will be a subset of @filter.
*
* Note that this function does not return writable #GstCaps, use
* gst_caps_make_writable() before modifying the caps.
*
* Returns: the caps of the pad with incremented ref-count.
*/
GstCaps *
gst_pad_get_caps (GstPad * pad, GstCaps * filter)
{
GstCaps *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), NULL);
GST_OBJECT_LOCK (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
result = gst_pad_get_caps_unlocked (pad, filter);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_peer_get_caps:
* @pad: a #GstPad to get the capabilities of.
* @filter: a #GstCaps filter.
*
* Gets the capabilities of the peer connected to this pad. Similar to
* gst_pad_get_caps().
*
* When called on srcpads @filter contains the caps that
* upstream could produce in the order preferred by upstream. When
* called on sinkpads @filter contains the caps accepted by
* downstream in the preffered order. @filter might be %NULL but
* if it is not %NULL the returned caps will be a subset of @filter.
*
* Returns: the caps of the peer pad with incremented ref-count. This function
* returns %NULL when there is no peer pad.
*/
GstCaps *
gst_pad_peer_get_caps (GstPad * pad, GstCaps * filter)
{
GstPad *peerpad;
GstCaps *result = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
g_return_val_if_fail (filter == NULL || GST_IS_CAPS (filter), 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, filter);
gst_object_unref (peerpad);
return result;
no_peer:
{
GST_OBJECT_UNLOCK (pad);
return NULL;
}
}
static void
gst_pad_fixate_caps_default (GstPad * pad, GstCaps * caps)
{
/* default fixation */
gst_caps_fixate (caps);
}
/**
* 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;
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (caps != NULL);
g_return_if_fail (!gst_caps_is_empty (caps));
g_return_if_fail (!gst_caps_is_any (caps));
if (gst_caps_is_fixed (caps) || gst_caps_is_any (caps))
return;
g_return_if_fail (gst_caps_is_writable (caps));
if (G_LIKELY ((fixatefunc = GST_PAD_FIXATECAPSFUNC (pad))))
fixatefunc (pad, caps);
}
/* 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 *allowed;
gboolean result = FALSE;
GST_DEBUG_OBJECT (pad, "caps %" GST_PTR_FORMAT, caps);
allowed = gst_pad_get_caps (pad, NULL);
if (!allowed)
goto nothing_allowed;
GST_DEBUG_OBJECT (pad, "allowed caps %" GST_PTR_FORMAT, allowed);
result = gst_caps_is_subset (caps, allowed);
gst_caps_unref (allowed);
return result;
/* ERRORS */
nothing_allowed:
{
GST_DEBUG_OBJECT (pad, "no caps allowed on the pad");
return FALSE;
}
}
/**
* 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;
#if 0
GstCaps *existing = NULL;
#endif
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_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
#if 0
GST_OBJECT_LOCK (pad);
/* 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);
#endif
acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
/* Only null if the element explicitly unset it */
if (G_UNLIKELY (acceptfunc == NULL))
goto no_func;
/* we can call the function */
result = acceptfunc (pad, caps);
GST_DEBUG_OBJECT (pad, "acceptfunc returned %d", result);
return result;
#if 0
is_same_caps:
{
GST_DEBUG_OBJECT (pad, "pad had same caps");
GST_OBJECT_UNLOCK (pad);
return TRUE;
}
#endif
no_func:
{
GST_DEBUG_OBJECT (pad, "no acceptcaps function");
return FALSE;
}
}
/**
* 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;
gst_object_ref (peerpad);
/* release lock before calling external methods but keep ref to pad */
GST_OBJECT_UNLOCK (pad);
result = gst_pad_accept_caps (peerpad, caps);
gst_object_unref (peerpad);
return result;
no_peer:
{
GST_OBJECT_UNLOCK (pad);
return TRUE;
}
}
/**
* gst_pad_set_caps:
* @pad: a #GstPad to set the capabilities of.
* @caps: (transfer none): 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)
{
GstEvent *event;
gboolean res = TRUE;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (caps != NULL && gst_caps_is_fixed (caps), FALSE);
event = gst_event_new_caps (caps);
if (GST_PAD_IS_SRC (pad))
res = gst_pad_push_event (pad, event);
else
res = gst_pad_send_event (pad, event);
return res;
}
static gboolean
do_event_function (GstPad * pad, GstEvent * event,
GstPadEventFunction eventfunc, gboolean * caps_notify)
{
gboolean result = TRUE, call_event = TRUE;
GstCaps *caps, *old, *templ;
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_CAPS:
{
/* backwards compatibility mode for caps */
gst_event_parse_caps (event, &caps);
/* See if pad accepts the caps */
templ = gst_pad_get_pad_template_caps (pad);
if (!gst_caps_is_subset (caps, templ))
goto not_accepted;
/* check if it changed */
if ((old = gst_pad_get_current_caps (pad))) {
call_event = !gst_caps_is_equal (caps, old);
gst_caps_unref (old);
}
if (call_event)
*caps_notify = TRUE;
gst_caps_unref (templ);
break;
}
default:
break;
}
if (call_event) {
GST_DEBUG_OBJECT (pad, "calling event function with event %p", event);
result = eventfunc (pad, event);
} else {
gst_event_unref (event);
}
return result;
/* ERRORS */
not_accepted:
{
gst_caps_unref (templ);
gst_event_unref (event);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"caps %" GST_PTR_FORMAT " not accepted", caps);
return FALSE;
}
}
/* function to send all pending events on the sinkpad to the event
* function and collect the results. This function should be called with
* the object lock. The object lock might be released by this function.
*/
static GstFlowReturn
gst_pad_update_events (GstPad * pad)
{
GstFlowReturn ret = GST_FLOW_OK;
guint i;
GstPadEventFunction eventfunc;
GstEvent *event;
gboolean caps_notify = FALSE;
if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
goto no_function;
for (i = 0; i < GST_EVENT_MAX_STICKY; i++) {
gboolean res;
PadEvent *ev;
ev = &pad->priv->events[i];
/* skip without pending event */
if ((event = gst_event_steal (&ev->pending)) == NULL)
continue;
gst_event_ref (event);
GST_OBJECT_UNLOCK (pad);
res = do_event_function (pad, event, eventfunc, &caps_notify);
/* things could have changed while we release the lock, check if we still
* are handling the same event, if we don't something changed and we have
* to try again. FIXME. we need a cookie here. FIXME, we also want to remove
* that lock eventually and then do the retry elsewhere. */
if (res) {
/* make the event active */
gst_event_take (&ev->event, event);
/* notify caps change when needed */
if (caps_notify) {
g_object_notify_by_pspec ((GObject *) pad, pspec_caps);
caps_notify = FALSE;
}
} else {
gst_event_unref (event);
ret = GST_FLOW_ERROR;
}
GST_OBJECT_LOCK (pad);
}
/* when we get here all events were successfully updated. */
return ret;
/* ERRORS */
no_function:
{
g_warning ("pad %s:%s has no event handler, file a bug.",
GST_DEBUG_PAD_NAME (pad));
return GST_FLOW_NOT_SUPPORTED;
}
}
/**
* gst_pad_get_pad_template_caps:
* @pad: a #GstPad to get the template capabilities from.
*
* Gets the capabilities for @pad's template.
*
* Returns: (transfer full): the #GstCaps of this pad template.
* Unref after usage.
*/
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_get_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: (transfer full): 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:
* @pad: a #GstPad.
*
* Gets the capabilities of the allowed media types that can flow through
* @pad and its peer.
*
* The allowed capabilities is calculated as the intersection of the results of
* calling gst_pad_get_caps() on @pad and its peer. The caller owns a reference
* on the resulting caps.
*
* Returns: (transfer full): the allowed #GstCaps of the pad link. Unref the
* caps when you no longer need it. This function returns NULL when @pad
* has no peer.
*
* MT safe.
*/
GstCaps *
gst_pad_get_allowed_caps (GstPad * pad)
{
GstCaps *mycaps;
GstCaps *caps;
GstCaps *peercaps;
GstPad *peer;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
peer = GST_PAD_PEER (pad);
if (G_UNLIKELY (peer == NULL))
goto no_peer;
GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting allowed caps");
gst_object_ref (peer);
GST_OBJECT_UNLOCK (pad);
mycaps = gst_pad_get_caps (pad, NULL);
peercaps = gst_pad_get_caps (peer, NULL);
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, pad, "allowed 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;
}
}
/**
* gst_pad_iterate_internal_links_default:
* @pad: the #GstPad to get the internal links of.
*
* Iterate the list of pads to which the given pad is linked to inside of
* the parent element.
* This is the default handler, and thus returns an iterator of all of the
* pads inside the parent element with opposite direction.
*
* The caller must free this iterator after use with gst_iterator_free().
*
* Returns: a #GstIterator of #GstPad, or NULL if @pad has no parent. Unref each
* returned pad with gst_object_unref().
*
* Since: 0.10.21
*/
GstIterator *
gst_pad_iterate_internal_links_default (GstPad * pad)
{
GstIterator *res;
GList **padlist;
guint32 *cookie;
GMutex *lock;
gpointer owner;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
{
GstElement *parent;
GST_OBJECT_LOCK (pad);
parent = GST_PAD_PARENT (pad);
if (!parent || !GST_IS_ELEMENT (parent))
goto no_parent;
gst_object_ref (parent);
GST_OBJECT_UNLOCK (pad);
if (pad->direction == GST_PAD_SRC)
padlist = &parent->sinkpads;
else
padlist = &parent->srcpads;
GST_DEBUG_OBJECT (pad, "Making iterator");
cookie = &parent->pads_cookie;
owner = parent;
lock = GST_OBJECT_GET_LOCK (parent);
}
res = gst_iterator_new_list (GST_TYPE_PAD,
lock, cookie, padlist, (GObject *) owner, NULL);
gst_object_unref (owner);
return res;
/* ERRORS */
no_parent:
{
GST_OBJECT_UNLOCK (pad);
GST_DEBUG_OBJECT (pad, "no parent element");
return NULL;
}
}
/**
* gst_pad_iterate_internal_links:
* @pad: the GstPad to get the internal links of.
*
* Gets an iterator for the pads to which the given pad is linked to inside
* of the parent element.
*
* Each #GstPad element yielded by the iterator will have its refcount increased,
* so unref after use.
*
* Free-function: gst_iterator_free
*
* Returns: (transfer full): a new #GstIterator of #GstPad or %NULL when the
* pad does not have an iterator function configured. Use
* gst_iterator_free() after usage.
*
* Since: 0.10.21
*/
GstIterator *
gst_pad_iterate_internal_links (GstPad * pad)
{
GstIterator *res = NULL;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
if (GST_PAD_ITERINTLINKFUNC (pad))
res = GST_PAD_ITERINTLINKFUNC (pad) (pad);
return res;
}
/**
* gst_pad_forward:
* @pad: a #GstPad
* @forward: a #GstPadForwardFunction
* @user_data: user data passed to @forward
*
* Calls @forward for all internally linked pads of @pad. This function deals with
* dynamically changing internal pads and will make sure that the @forward
* function is only called once for each pad.
*
* When @forward returns TRUE, no further pads will be processed.
*
* Returns: TRUE if one of the dispatcher functions returned TRUE.
*/
gboolean
gst_pad_forward (GstPad * pad, GstPadForwardFunction forward,
gpointer user_data)
{
gboolean result = FALSE;
GstIterator *iter;
gboolean done = FALSE;
GValue item = { 0, };
GList *pushed_pads = NULL;
iter = gst_pad_iterate_internal_links (pad);
if (!iter)
goto no_iter;
while (!done) {
switch (gst_iterator_next (iter, &item)) {
case GST_ITERATOR_OK:
{
GstPad *intpad;
intpad = g_value_get_object (&item);
/* if already pushed, skip. FIXME, find something faster to tag pads */
if (g_list_find (pushed_pads, intpad)) {
g_value_reset (&item);
break;
}
GST_LOG_OBJECT (pad, "calling forward function on pad %s:%s",
GST_DEBUG_PAD_NAME (intpad));
done = result = forward (intpad, user_data);
pushed_pads = g_list_prepend (pushed_pads, intpad);
g_value_reset (&item);
break;
}
case GST_ITERATOR_RESYNC:
/* We don't reset the result here because we don't push the event
* again on pads that got the event already and because we need
* to consider the result of the previous pushes */
gst_iterator_resync (iter);
break;
case GST_ITERATOR_ERROR:
GST_ERROR_OBJECT (pad, "Could not iterate over internally linked pads");
done = TRUE;
break;
case GST_ITERATOR_DONE:
done = TRUE;
break;
}
}
g_value_unset (&item);
gst_iterator_free (iter);
g_list_free (pushed_pads);
no_iter:
return result;
}
typedef struct
{
GstEvent *event;
gboolean result;
gboolean dispatched;
} EventData;
static gboolean
event_forward_func (GstPad * pad, EventData * data)
{
/* 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 pushing event %p (%s) to %s:%s",
data->event, GST_EVENT_TYPE_NAME (data->event), GST_DEBUG_PAD_NAME (pad));
data->result |= gst_pad_push_event (pad, gst_event_ref (data->event));
data->dispatched = TRUE;
/* don't stop */
return FALSE;
}
/**
* gst_pad_event_default:
* @pad: a #GstPad to call the default event handler on.
* @event: (transfer full): the #GstEvent to handle.
*
* Invokes the default event handler for the given pad.
*
* The EOS event will pause the task associated with @pad before it is forwarded
* to all internally linked pads,
*
* The CAPS event will never be forwarded.
*
* The the event is sent to all pads internally linked to @pad. This function
* takes ownership of @event.
*
* Returns: TRUE if the event was sent successfully.
*/
gboolean
gst_pad_event_default (GstPad * pad, GstEvent * event)
{
gboolean result;
EventData data;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
GST_LOG_OBJECT (pad, "default event handler");
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_EOS:
{
GST_DEBUG_OBJECT (pad, "pausing task because of eos");
gst_pad_pause_task (pad);
break;
}
default:
break;
}
data.event = event;
data.dispatched = FALSE;
data.result = FALSE;
gst_pad_forward (pad, (GstPadForwardFunction) event_forward_func, &data);
/* for sinkpads without a parent element or without internal links, nothing
* will be dispatched but we still want to return TRUE. */
if (data.dispatched)
result = data.result;
else
result = TRUE;
gst_event_unref (event);
return result;
}
/**
* gst_pad_query:
* @pad: a #GstPad to invoke the default query on.
* @query: (transfer none): 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. The element that
* the pad belongs to 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.
*
* Please also note that some queries might need a running pipeline to work.
*
* Returns: TRUE if the query could be performed.
*/
gboolean
gst_pad_query (GstPad * pad, GstQuery * query)
{
gboolean res;
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 (%s)", query,
GST_QUERY_TYPE_NAME (query));
if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
goto no_func;
res = func (pad, query);
GST_DEBUG_OBJECT (pad, "sent query %p (%s), result %d", query,
GST_QUERY_TYPE_NAME (query), res);
return res;
no_func:
{
GST_DEBUG_OBJECT (pad, "had no query function");
return FALSE;
}
}
/**
* gst_pad_peer_query:
* @pad: a #GstPad to invoke the peer query on.
* @query: (transfer none): the #GstQuery to perform.
*
* Performs gst_pad_query() on the peer of @pad.
*
* The caller is responsible for both the allocation and deallocation of
* the query structure.
*
* Returns: TRUE if the query could be performed. This function returns %FALSE
* if @pad has no peer.
*
* Since: 0.10.15
*/
gboolean
gst_pad_peer_query (GstPad * pad, GstQuery * query)
{
GstPad *peerpad;
gboolean result;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
GST_OBJECT_LOCK (pad);
GST_DEBUG_OBJECT (pad, "peer query %p (%s)", query,
GST_QUERY_TYPE_NAME (query));
peerpad = GST_PAD_PEER (pad);
if (G_UNLIKELY (peerpad == NULL))
goto no_peer;
gst_object_ref (peerpad);
GST_OBJECT_UNLOCK (pad);
result = gst_pad_query (peerpad, query);
gst_object_unref (peerpad);
return result;
/* ERRORS */
no_peer:
{
GST_WARNING_OBJECT (pad, "pad has no peer");
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
}
/**
* gst_pad_query_default:
* @pad: a #GstPad to call the default query handler on.
* @query: (transfer none): 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 successfully.
*/
gboolean
gst_pad_query_default (GstPad * pad, GstQuery * query)
{
gboolean forward = TRUE, ret = FALSE;
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_SCHEDULING:
forward = FALSE;
break;
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:
case GST_QUERY_ALLOCATION:
default:
break;
}
if (forward) {
ret = gst_pad_forward
(pad, (GstPadForwardFunction) gst_pad_peer_query, query);
}
return ret;
}
static void
probe_hook_marshal (GHook * hook, ProbeMarshall * data)
{
GstPad *pad = data->pad;
GstProbeType flags;
GstPadProbeCallback callback;
GstProbeReturn ret;
/* if we have called this callback, do nothing */
if (PROBE_COOKIE (hook) == data->cookie)
return;
PROBE_COOKIE (hook) = data->cookie;
flags = hook->flags >> G_HOOK_FLAG_USER_SHIFT;
/* one of the data types */
if ((flags & GST_PROBE_TYPE_DATA & data->mask) == 0)
return;
/* one of the scheduling types */
if ((flags & GST_PROBE_TYPE_SCHEDULING & data->mask) == 0)
return;
/* all of the blocking types must match */
if ((flags & GST_PROBE_TYPE_BLOCKING) !=
(data->mask & GST_PROBE_TYPE_BLOCKING))
return;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"hook %lu with flags 0x%08x matches", hook->hook_id, flags);
callback = (GstPadProbeCallback) hook->func;
if (callback == NULL)
return;
GST_OBJECT_UNLOCK (pad);
ret = callback (pad, data->mask, data->type_data, hook->data);
GST_OBJECT_LOCK (pad);
switch (ret) {
case GST_PROBE_REMOVE:
/* remove the probe */
GST_DEBUG_OBJECT (pad, "asked to remove hook");
cleanup_hook (pad, hook);
break;
case GST_PROBE_DROP:
/* need to drop the data, make sure other probes don't get called
* anymore */
GST_DEBUG_OBJECT (pad, "asked to drop item");
data->mask = GST_PROBE_TYPE_INVALID;
data->ret = GST_PROBE_DROP;
break;
case GST_PROBE_PASS:
/* inform the pad block to let things pass */
GST_DEBUG_OBJECT (pad, "asked to pass item");
data->pass = TRUE;
break;
default:
GST_DEBUG_OBJECT (pad, "probe returned %d", ret);
break;
}
}
#define PROBE(pad,mask,data,label) \
G_STMT_START { \
if (G_UNLIKELY (pad->num_probes)) { \
ret = do_probe_callbacks (pad, mask, data); \
if (G_UNLIKELY (ret != GST_FLOW_OK)) \
goto label; \
} \
} G_STMT_END
static GstFlowReturn
do_probe_callbacks (GstPad * pad, GstProbeType mask, gpointer type_data)
{
ProbeMarshall data;
guint cookie;
data.pad = pad;
data.mask = mask;
data.type_data = type_data;
data.ret = GST_PROBE_OK;
data.pass = FALSE;
data.cookie = pad->priv->probe_cookie++;
again:
cookie = pad->priv->probe_cookie;
g_hook_list_marshal (&pad->probes, FALSE,
(GHookMarshaller) probe_hook_marshal, &data);
/* if the list changed, call the new callbacks (they will not have their
* cookie set to data.cookie */
if (cookie != pad->priv->probe_cookie) {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"probe list changed, restarting");
goto again;
}
if (data.ret == GST_PROBE_DROP)
goto dropped;
if (data.pass)
goto passed;
if (mask & GST_PROBE_TYPE_BLOCK) {
while (GST_PAD_IS_BLOCKED (pad)) {
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"we are blocked %d times", pad->num_blocked);
/* we might have released the lock */
if (G_UNLIKELY (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_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"Waiting to be unblocked or set flushing");
GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKING);
GST_PAD_BLOCK_WAIT (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKING);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "We got unblocked");
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
}
}
return GST_FLOW_OK;
/* ERRORS */
flushing:
{
GST_DEBUG_OBJECT (pad, "pad is flushing");
return GST_FLOW_WRONG_STATE;
}
dropped:
{
GST_DEBUG_OBJECT (pad, "data is dropped");
return GST_FLOW_CUSTOM_SUCCESS;
}
passed:
{
GST_DEBUG_OBJECT (pad, "data is passed");
return GST_FLOW_OK;
}
}
/* pad offsets */
/**
* gst_pad_get_offset:
* @pad: a #GstPad
*
* Get the offset applied to the running time of @pad. @pad has to be a source
* pad.
*
* Returns: the offset.
*/
gint64
gst_pad_get_offset (GstPad * pad)
{
gint64 result;
g_return_val_if_fail (GST_IS_PAD (pad), 0);
GST_OBJECT_LOCK (pad);
result = pad->offset;
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_set_offset:
* @pad: a #GstPad
* @offset: the offset
*
* Set the offset that will be applied to the running time of @pad.
*/
void
gst_pad_set_offset (GstPad * pad, gint64 offset)
{
guint idx;
GstPad *peer;
GstPad *tmp = NULL;
g_return_if_fail (GST_IS_PAD (pad));
GST_OBJECT_LOCK (pad);
/* if nothing changed, do nothing */
if (pad->offset == offset)
goto done;
pad->offset = offset;
/* if no peer, we just updated the offset */
if ((peer = GST_PAD_PEER (pad)) == NULL)
goto done;
/* switch pads around when dealing with a sinkpad */
if (GST_PAD_IS_SINK (pad)) {
/* ref the peer so it doesn't go away when we release the lock */
tmp = gst_object_ref (peer);
/* make sure we get the peer (the srcpad) */
GST_OBJECT_UNLOCK (pad);
/* swap pads */
peer = pad;
pad = tmp;
GST_OBJECT_LOCK (pad);
/* check if the pad didn't get relinked */
if (GST_PAD_PEER (pad) != peer)
goto done;
/* we can release the ref now */
gst_object_unref (peer);
}
/* the index of the segment event in the array */
idx = GST_EVENT_STICKY_IDX_TYPE (GST_EVENT_SEGMENT);
/* lock order is srcpad >> sinkpad */
GST_OBJECT_LOCK (peer);
/* take the current segment event, adjust it and then place
* it on the sinkpad. events on the srcpad are always active. */
if (replace_event (pad, peer, idx))
GST_OBJECT_FLAG_SET (peer, GST_PAD_NEED_EVENTS);
GST_OBJECT_UNLOCK (peer);
done:
GST_OBJECT_UNLOCK (pad);
}
/**********************************************************************
* Data passing functions
*/
/* this is the chain function that does not perform the additional argument
* checking for that little extra speed.
*/
static inline GstFlowReturn
gst_pad_chain_data_unchecked (GstPad * pad, GstProbeType type, void *data)
{
GstFlowReturn ret;
gboolean needs_events;
GST_PAD_STREAM_LOCK (pad);
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
needs_events = GST_PAD_NEEDS_EVENTS (pad);
if (G_UNLIKELY (needs_events)) {
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_NEED_EVENTS);
GST_DEBUG_OBJECT (pad, "need to update all events");
ret = gst_pad_update_events (pad);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto events_error;
}
PROBE (pad, GST_PROBE_TYPE_PUSH | type, data, probe_stopped);
GST_OBJECT_UNLOCK (pad);
/* 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_LIKELY (type & GST_PROBE_TYPE_BUFFER)) {
GstPadChainFunction chainfunc;
if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
goto no_function;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"calling chainfunction &%s with buffer %p, ts %" GST_TIME_FORMAT,
GST_DEBUG_FUNCPTR_NAME (chainfunc),
GST_BUFFER (data), GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (data)));
ret = chainfunc (pad, GST_BUFFER_CAST (data));
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"called chainfunction &%s with buffer %p, returned %s",
GST_DEBUG_FUNCPTR_NAME (chainfunc), data, gst_flow_get_name (ret));
} else {
GstPadChainListFunction chainlistfunc;
if (G_UNLIKELY ((chainlistfunc = GST_PAD_CHAINLISTFUNC (pad)) == NULL))
goto no_function;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"calling chainlistfunction &%s",
GST_DEBUG_FUNCPTR_NAME (chainlistfunc));
ret = chainlistfunc (pad, GST_BUFFER_LIST_CAST (data));
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"called chainlistfunction &%s, returned %s",
GST_DEBUG_FUNCPTR_NAME (chainlistfunc), gst_flow_get_name (ret));
}
GST_PAD_STREAM_UNLOCK (pad);
return ret;
/* ERRORS */
flushing:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"chaining, but pad was flushing");
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_WRONG_STATE;
}
events_error:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "events were not accepted");
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
return ret;
}
probe_stopped:
{
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
gst_mini_object_unref (GST_MINI_OBJECT_CAST (data));
switch (ret) {
case GST_FLOW_CUSTOM_SUCCESS:
GST_DEBUG_OBJECT (pad, "dropped buffer");
ret = GST_FLOW_OK;
break;
default:
GST_DEBUG_OBJECT (pad, "en error occured %s", gst_flow_get_name (ret));
break;
}
return ret;
}
no_function:
{
gst_mini_object_unref (GST_MINI_OBJECT_CAST (data));
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: (transfer full): 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 buffer type is not acceptable for @pad (as negotiated with a
* preceeding GST_EVENT_CAPS event), 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_IS_SINK (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
return gst_pad_chain_data_unchecked (pad, GST_PROBE_TYPE_BUFFER, buffer);
}
static GstFlowReturn
gst_pad_chain_list_default (GstPad * pad, GstBufferList * list)
{
guint i, len;
GstBuffer *buffer;
GstFlowReturn ret;
GST_INFO_OBJECT (pad, "chaining each group in list as a merged buffer");
len = gst_buffer_list_len (list);
ret = GST_FLOW_OK;
for (i = 0; i < len; i++) {
buffer = gst_buffer_list_get (list, i);
ret =
gst_pad_chain_data_unchecked (pad, GST_PROBE_TYPE_BUFFER,
gst_buffer_ref (buffer));
if (ret != GST_FLOW_OK)
break;
}
gst_buffer_list_unref (list);
return ret;
}
/**
* gst_pad_chain_list:
* @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
* @list: (transfer full): the #GstBufferList to send, return GST_FLOW_ERROR
* if not.
*
* Chain a bufferlist to @pad.
*
* The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
*
* If @pad was not negotiated properly with a CAPS event, this function
* returns #GST_FLOW_NOT_NEGOTIATED.
*
* The function proceeds calling the chainlist function installed on @pad (see
* gst_pad_set_chain_list_function()) and the return value of that function is
* returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
* chainlist function.
*
* In all cases, success or failure, the caller loses its reference to @list
* after calling this function.
*
* MT safe.
*
* Returns: a #GstFlowReturn from the pad.
*
* Since: 0.10.24
*/
GstFlowReturn
gst_pad_chain_list (GstPad * pad, GstBufferList * list)
{
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
return gst_pad_chain_data_unchecked (pad, GST_PROBE_TYPE_BUFFER_LIST, list);
}
static GstFlowReturn
gst_pad_push_data (GstPad * pad, GstProbeType type, void *data)
{
GstPad *peer;
GstFlowReturn ret;
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
type |= GST_PROBE_TYPE_PUSH;
/* do block probes */
PROBE (pad, type | GST_PROBE_TYPE_BLOCK, data, probe_stopped);
/* do post-blocking probes */
PROBE (pad, type, data, probe_stopped);
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);
pad->priv->using++;
GST_OBJECT_UNLOCK (pad);
ret = gst_pad_chain_data_unchecked (peer, type, data);
gst_object_unref (peer);
GST_OBJECT_LOCK (pad);
pad->priv->using--;
if (pad->priv->using == 0) {
/* pad is not active anymore, trigger idle callbacks */
PROBE (pad, GST_PROBE_TYPE_PUSH | GST_PROBE_TYPE_IDLE, NULL, probe_stopped);
}
GST_OBJECT_UNLOCK (pad);
return ret;
/* ERROR recovery here */
/* ERRORS */
flushing:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but pad was flushing");
GST_OBJECT_UNLOCK (pad);
gst_mini_object_unref (GST_MINI_OBJECT_CAST (data));
return GST_FLOW_WRONG_STATE;
}
probe_stopped:
{
GST_OBJECT_UNLOCK (pad);
gst_mini_object_unref (GST_MINI_OBJECT_CAST (data));
switch (ret) {
case GST_FLOW_CUSTOM_SUCCESS:
GST_DEBUG_OBJECT (pad, "dropped buffer");
ret = GST_FLOW_OK;
break;
default:
GST_DEBUG_OBJECT (pad, "en error occured %s", gst_flow_get_name (ret));
break;
}
return ret;
}
not_linked:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pushing, but it was not linked");
GST_OBJECT_UNLOCK (pad);
gst_mini_object_unref (GST_MINI_OBJECT_CAST (data));
return GST_FLOW_NOT_LINKED;
}
}
/**
* gst_pad_push:
* @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
* @buffer: (transfer full): the #GstBuffer to push returns GST_FLOW_ERROR
* if not.
*
* Pushes a buffer to the peer of @pad.
*
* This function will call installed block probes before triggering any
* installed data probes.
*
* 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)
{
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 (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
return gst_pad_push_data (pad, GST_PROBE_TYPE_BUFFER, buffer);
}
/**
* gst_pad_push_list:
* @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
* @list: (transfer full): the #GstBufferList to push returns GST_FLOW_ERROR
* if not.
*
* Pushes a buffer list to the peer of @pad.
*
* This function will call installed block probes before triggering any
* installed data probes.
*
* The function proceeds calling the chain function on the peer pad and returns
* the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
* be returned. If the peer pad does not have any installed chainlist function
* every group buffer of the list will be merged into a normal #GstBuffer and
* chained via gst_pad_chain().
*
* In all cases, success or failure, the caller loses its reference to @list
* after calling this function.
*
* Returns: a #GstFlowReturn from the peer pad.
*
* MT safe.
*
* Since: 0.10.24
*/
GstFlowReturn
gst_pad_push_list (GstPad * pad, GstBufferList * list)
{
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 (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
return gst_pad_push_data (pad, GST_PROBE_TYPE_BUFFER_LIST, list);
}
static GstFlowReturn
gst_pad_get_range_unchecked (GstPad * pad, guint64 offset, guint size,
GstBuffer ** buffer)
{
GstFlowReturn ret;
GstPadGetRangeFunction getrangefunc;
GST_PAD_STREAM_LOCK (pad);
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
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);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto get_range_failed;
/* can only fire the signal if we have a valid buffer */
GST_OBJECT_LOCK (pad);
PROBE (pad, GST_PROBE_TYPE_PULL | GST_PROBE_TYPE_BUFFER, *buffer,
probe_stopped);
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
return ret;
/* ERRORS */
flushing:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"getrange, 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),
("getrange on pad %s:%s but it has no getrangefunction",
GST_DEBUG_PAD_NAME (pad)));
GST_PAD_STREAM_UNLOCK (pad);
return GST_FLOW_NOT_SUPPORTED;
}
probe_stopped:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"probe returned %s", gst_flow_get_name (ret));
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
gst_buffer_unref (*buffer);
*buffer = NULL;
return ret;
}
get_range_failed:
{
GST_PAD_STREAM_UNLOCK (pad);
*buffer = NULL;
GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
(ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
pad, "getrange failed, flow: %s", gst_flow_get_name (ret));
return ret;
}
}
/**
* 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: (out callee-allocates): a pointer to hold the #GstBuffer,
* returns #GST_FLOW_ERROR if %NULL.
*
* When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
* immediately and @buffer is %NULL.
*
* 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.
*
* This is a lowlevel function. Usualy gst_pad_pull_range() is used.
*
* Returns: a #GstFlowReturn from the pad.
*
* MT safe.
*/
GstFlowReturn
gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
GstBuffer ** buffer)
{
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 (buffer != NULL, GST_FLOW_ERROR);
return gst_pad_get_range_unchecked (pad, offset, size, buffer);
}
/**
* 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: (out callee-allocates): 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 needs_events;
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
GST_OBJECT_LOCK (pad);
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
PROBE (pad, GST_PROBE_TYPE_PULL | GST_PROBE_TYPE_BLOCK, NULL,
pre_probe_stopped);
if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
goto not_linked;
gst_object_ref (peer);
pad->priv->using++;
GST_OBJECT_UNLOCK (pad);
ret = gst_pad_get_range_unchecked (peer, offset, size, buffer);
gst_object_unref (peer);
GST_OBJECT_LOCK (pad);
pad->priv->using--;
if (pad->priv->using == 0) {
/* pad is not active anymore, trigger idle callbacks */
PROBE (pad, GST_PROBE_TYPE_PULL | GST_PROBE_TYPE_IDLE, NULL,
post_probe_stopped);
}
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto pull_range_failed;
PROBE (pad, GST_PROBE_TYPE_PULL | GST_PROBE_TYPE_BUFFER, buffer,
post_probe_stopped);
needs_events = GST_PAD_NEEDS_EVENTS (pad);
if (G_UNLIKELY (needs_events)) {
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_NEED_EVENTS);
GST_DEBUG_OBJECT (pad, "we need to update the events");
ret = gst_pad_update_events (pad);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto events_error;
}
GST_OBJECT_UNLOCK (pad);
return ret;
/* ERROR recovery here */
flushing:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pullrange, but pad was flushing");
GST_OBJECT_UNLOCK (pad);
return GST_FLOW_WRONG_STATE;
}
pre_probe_stopped:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pre probe returned %s",
gst_flow_get_name (ret));
GST_OBJECT_UNLOCK (pad);
return ret;
}
not_linked:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pulling range, but it was not linked");
GST_OBJECT_UNLOCK (pad);
return GST_FLOW_NOT_LINKED;
}
pull_range_failed:
{
*buffer = NULL;
GST_OBJECT_UNLOCK (pad);
GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
(ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
pad, "pullrange failed, flow: %s", gst_flow_get_name (ret));
return ret;
}
post_probe_stopped:
{
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"post probe returned %s", gst_flow_get_name (ret));
GST_OBJECT_UNLOCK (pad);
if (ret == GST_FLOW_OK)
gst_buffer_unref (*buffer);
*buffer = NULL;
return ret;
}
events_error:
{
GST_OBJECT_UNLOCK (pad);
gst_buffer_unref (*buffer);
*buffer = NULL;
GST_CAT_WARNING_OBJECT (GST_CAT_SCHEDULING, pad,
"pullrange returned events that were not accepted");
return ret;
}
}
/**
* gst_pad_push_event:
* @pad: a #GstPad to push the event to.
* @event: (transfer full): 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)
{
GstFlowReturn ret;
GstPad *peerpad;
gboolean result;
gboolean stored = FALSE;
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_OBJECT_LOCK (pad);
peerpad = GST_PAD_PEER (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 blocking pad. This
* will typically unblock the STREAMING thread blocked on a pad. */
GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-start, "
"doing block signal.");
GST_PAD_BLOCK_BROADCAST (pad);
goto flushed;
}
break;
case GST_EVENT_FLUSH_STOP:
GST_PAD_UNSET_FLUSHING (pad);
if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-stop");
goto flushed;
}
break;
default:
{
/* store the event on the pad, but only on srcpads */
if (GST_PAD_IS_SRC (pad) && GST_EVENT_IS_STICKY (event)) {
guint idx;
idx = GST_EVENT_STICKY_IDX (event);
GST_LOG_OBJECT (pad, "storing sticky event %s at index %u",
GST_EVENT_TYPE_NAME (event), idx);
/* srcpad sticky events always become active immediately */
gst_event_replace (&pad->priv->events[idx].event, event);
stored = TRUE;
}
/* backwards compatibility mode for caps */
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_CAPS:
{
GST_OBJECT_UNLOCK (pad);
g_object_notify_by_pspec ((GObject *) pad, pspec_caps);
GST_OBJECT_LOCK (pad);
/* the peerpad might have changed. Things we checked above could not
* have changed. */
peerpad = GST_PAD_PEER (pad);
break;
}
case GST_EVENT_SEGMENT:
{
gint64 offset;
offset = pad->offset;
/* check if we need to adjust the segment */
if (offset != 0 && (peerpad != NULL)) {
GstSegment segment;
/* copy segment values */
gst_event_copy_segment (event, &segment);
gst_event_unref (event);
/* adjust and make a new event with the offset applied */
segment.base += offset;
event = gst_event_new_segment (&segment);
}
break;
}
case GST_EVENT_RECONFIGURE:
if (GST_PAD_IS_SINK (pad))
GST_OBJECT_FLAG_SET (pad, GST_PAD_NEED_RECONFIGURE);
break;
default:
break;
}
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushed;
PROBE (pad, GST_PROBE_TYPE_PUSH | GST_PROBE_TYPE_EVENT
| GST_PROBE_TYPE_BLOCK, event, probe_stopped);
break;
}
}
/* send probes after modifying the events above */
PROBE (pad, GST_PROBE_TYPE_PUSH | GST_PROBE_TYPE_EVENT, event, probe_stopped);
/* now check the peer pad */
if (peerpad == NULL)
goto not_linked;
gst_object_ref (peerpad);
pad->priv->using++;
GST_OBJECT_UNLOCK (pad);
GST_LOG_OBJECT (pad, "sending event %p (%s) to peerpad %" GST_PTR_FORMAT,
event, GST_EVENT_TYPE_NAME (event), peerpad);
result = gst_pad_send_event (peerpad, event);
/* Note: we gave away ownership of the event at this point but we can still
* print the old pointer */
GST_LOG_OBJECT (pad,
"sent event %p to peerpad %" GST_PTR_FORMAT ", result %d", event, peerpad,
result);
gst_object_unref (peerpad);
GST_OBJECT_LOCK (pad);
pad->priv->using--;
if (pad->priv->using == 0) {
/* pad is not active anymore, trigger idle callbacks */
PROBE (pad, GST_PROBE_TYPE_PUSH | GST_PROBE_TYPE_IDLE, NULL, probe_stopped);
}
GST_OBJECT_UNLOCK (pad);
return result | stored;
/* ERROR handling */
flushed:
{
GST_DEBUG_OBJECT (pad, "We're flushing");
GST_OBJECT_UNLOCK (pad);
gst_event_unref (event);
return stored;
}
probe_stopped:
{
GST_DEBUG_OBJECT (pad, "Probe returned %s", gst_flow_get_name (ret));
GST_OBJECT_UNLOCK (pad);
gst_event_unref (event);
return stored;
}
not_linked:
{
GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
GST_OBJECT_UNLOCK (pad);
gst_event_unref (event);
return stored;
}
}
/**
* gst_pad_send_event:
* @pad: a #GstPad to send the event to.
* @event: (transfer full): 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)
{
GstFlowReturn ret;
gboolean result = FALSE;
gboolean serialized, need_unlock = FALSE, needs_events, sticky;
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);
sticky = GST_EVENT_IS_STICKY (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 and sticky */
serialized = sticky = FALSE;
} else
goto unknown_direction;
/* get the flag first, we clear it when we have a FLUSH or a non-serialized
* event. */
needs_events = GST_PAD_NEEDS_EVENTS (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");
needs_events = FALSE;
break;
case GST_EVENT_FLUSH_STOP:
if (G_LIKELY (GST_PAD_ACTIVATE_MODE (pad) != GST_ACTIVATE_NONE)) {
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);
needs_events = FALSE;
break;
case GST_EVENT_RECONFIGURE:
if (GST_PAD_IS_SRC (pad))
GST_OBJECT_FLAG_SET (pad, GST_PAD_NEED_RECONFIGURE);
default:
GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
GST_EVENT_TYPE_NAME (event));
if (serialized) {
/* lock order: STREAM_LOCK, LOCK, recheck flushing. */
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_LOCK (pad);
need_unlock = TRUE;
GST_OBJECT_LOCK (pad);
} else {
/* don't forward events on non-serialized events */
needs_events = FALSE;
}
/* store the event on the pad, but only on srcpads. We need to store the
* event before checking the flushing flag. */
if (sticky) {
guint idx;
PadEvent *ev;
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_SEGMENT:
if (pad->offset != 0) {
GstSegment segment;
/* copy segment values */
gst_event_copy_segment (event, &segment);
gst_event_unref (event);
/* adjust and make a new event with the offset applied */
segment.base += pad->offset;
event = gst_event_new_segment (&segment);
}
break;
default:
break;
}
idx = GST_EVENT_STICKY_IDX (event);
ev = &pad->priv->events[idx];
if (ev->event != event) {
GST_LOG_OBJECT (pad, "storing sticky event %s at index %u",
GST_EVENT_TYPE_NAME (event), idx);
gst_event_replace (&ev->pending, event);
/* set the flag so that we update the events next time. We would
* usually update below but we might be flushing too. */
GST_OBJECT_FLAG_SET (pad, GST_PAD_NEED_EVENTS);
needs_events = TRUE;
}
}
/* now do the probe */
if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
goto flushing;
PROBE (pad, GST_PROBE_TYPE_PUSH | GST_PROBE_TYPE_EVENT, event,
probe_stopped);
break;
}
if (G_UNLIKELY (needs_events)) {
GstFlowReturn ret;
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_NEED_EVENTS);
GST_DEBUG_OBJECT (pad, "need to update all events");
ret = gst_pad_update_events (pad);
if (ret != GST_FLOW_OK)
goto update_failed;
GST_OBJECT_UNLOCK (pad);
gst_event_unref (event);
result = TRUE;
}
/* ensure to pass on event;
* note that a sticky event has already been updated above */
if (G_LIKELY (!needs_events || !sticky)) {
GstPadEventFunction eventfunc;
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);
GST_DEBUG_OBJECT (pad, "sent event, result %d", result);
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);
if (need_unlock)
GST_PAD_STREAM_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;
}
probe_stopped:
{
GST_DEBUG_OBJECT (pad, "probe returned %s", gst_flow_get_name (ret));
GST_OBJECT_UNLOCK (pad);
if (need_unlock)
GST_PAD_STREAM_UNLOCK (pad);
gst_event_unref (event);
return FALSE;
}
update_failed:
{
GST_OBJECT_UNLOCK (pad);
if (need_unlock)
GST_PAD_STREAM_UNLOCK (pad);
GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad, "Update events failed");
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: (transfer none): a #gpointer to the private data.
*/
gpointer
gst_pad_get_element_private (GstPad * pad)
{
return pad->element_private;
}
/**
* gst_pad_get_sticky_event:
* @pad: the #GstPad to get the event from.
* @event_type: the #GstEventType that should be retrieved.
*
* Returns a new reference of the sticky event of type @event_type
* from the event.
*
* Returns: (transfer full): a #GstEvent of type @event_type. Unref after usage.
*/
GstEvent *
gst_pad_get_sticky_event (GstPad * pad, GstEventType event_type)
{
GstEvent *event = NULL;
guint idx;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
g_return_val_if_fail ((event_type & GST_EVENT_TYPE_STICKY) != 0, NULL);
idx = GST_EVENT_STICKY_IDX_TYPE (event_type);
GST_OBJECT_LOCK (pad);
if ((event = pad->priv->events[idx].event)) {
gst_event_ref (event);
}
GST_OBJECT_UNLOCK (pad);
return event;
}
/**
* gst_pad_sticky_events_foreach:
* @pad: the #GstPad that should be used for iteration.
* @foreach_func: (scope call): the #GstPadStickyEventsForeachFunction that should be called for every event.
* @user_data: (closure): the optional user data.
*
* Iterates all active sticky events on @pad and calls @foreach_func for every
* event. If @foreach_func returns something else than GST_FLOW_OK the iteration
* is immediately stopped.
*
* Returns: GST_FLOW_OK if iteration was successful
*/
GstFlowReturn
gst_pad_sticky_events_foreach (GstPad * pad,
GstPadStickyEventsForeachFunction foreach_func, gpointer user_data)
{
GstFlowReturn ret = GST_FLOW_OK;
guint i;
GstEvent *event;
g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
g_return_val_if_fail (foreach_func != NULL, GST_FLOW_ERROR);
GST_OBJECT_LOCK (pad);
restart:
for (i = 0; i < GST_EVENT_MAX_STICKY; i++) {
gboolean res;
PadEvent *ev;
ev = &pad->priv->events[i];
/* skip without active event */
if ((event = ev->event) == NULL)
continue;
gst_event_ref (event);
GST_OBJECT_UNLOCK (pad);
res = foreach_func (pad, event, user_data);
GST_OBJECT_LOCK (pad);
gst_event_unref (event);
if (res != GST_FLOW_OK) {
ret = res;
break;
}
/* things could have changed while we release the lock, check if we still
* are handling the same event, if we don't something changed and we have
* to try again. FIXME. we need a cookie here. */
if (event != ev->event) {
GST_DEBUG_OBJECT (pad, "events changed, restarting");
goto restart;
}
}
GST_OBJECT_UNLOCK (pad);
return ret;
}
static void
do_stream_status (GstPad * pad, GstStreamStatusType type,
GThread * thread, GstTask * task)
{
GstElement *parent;
GST_DEBUG_OBJECT (pad, "doing stream-status %d", type);
if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (pad)))) {
if (GST_IS_ELEMENT (parent)) {
GstMessage *message;
GValue value = { 0 };
if (type == GST_STREAM_STATUS_TYPE_ENTER) {
gchar *tname, *ename, *pname;
/* create a good task name */
ename = gst_element_get_name (parent);
pname = gst_pad_get_name (pad);
tname = g_strdup_printf ("%s:%s", ename, pname);
g_free (ename);
g_free (pname);
gst_object_set_name (GST_OBJECT_CAST (task), tname);
g_free (tname);
}
message = gst_message_new_stream_status (GST_OBJECT_CAST (pad),
type, parent);
g_value_init (&value, GST_TYPE_TASK);
g_value_set_object (&value, task);
gst_message_set_stream_status_object (message, &value);
g_value_unset (&value);
GST_DEBUG_OBJECT (pad, "posting stream-status %d", type);
gst_element_post_message (parent, message);
}
gst_object_unref (parent);
}
}
static void
pad_enter_thread (GstTask * task, GThread * thread, gpointer user_data)
{
do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_ENTER,
thread, task);
}
static void
pad_leave_thread (GstTask * task, GThread * thread, gpointer user_data)
{
do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_LEAVE,
thread, task);
}
static GstTaskThreadCallbacks thr_callbacks = {
pad_enter_thread,
pad_leave_thread,
};
/**
* 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 repeatedly calls @func with @data. This function
* is mostly used in pad activation functions to start the dataflow.
* The #GST_PAD_STREAM_LOCK of @pad will automatically be acquired
* before @func is called.
*
* Returns: a %TRUE if the task could be started.
*/
gboolean
gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
{
GstTask *task;
gboolean res;
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_task_set_thread_callbacks (task, &thr_callbacks, pad, NULL);
GST_DEBUG_OBJECT (pad, "created task");
GST_PAD_TASK (pad) = task;
gst_object_ref (task);
/* release lock to post the message */
GST_OBJECT_UNLOCK (pad);
do_stream_status (pad, GST_STREAM_STATUS_TYPE_CREATE, NULL, task);
gst_object_unref (task);
GST_OBJECT_LOCK (pad);
/* nobody else is supposed to have changed the pad now */
if (GST_PAD_TASK (pad) != task)
goto concurrent_stop;
}
res = gst_task_set_state (task, GST_TASK_STARTED);
GST_OBJECT_UNLOCK (pad);
return res;
/* ERRORS */
concurrent_stop:
{
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 wait until the
* function executed by the task is finished if this function is not
* called from the task function.
*
* 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;
gboolean res;
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;
res = gst_task_set_state (task, GST_TASK_PAUSED);
GST_OBJECT_UNLOCK (pad);
/* wait for task function to finish, this lock is recursive so it does nothing
* when the pause is called from the task itself */
GST_PAD_STREAM_LOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
return res;
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;
gboolean res;
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;
res = gst_task_set_state (task, GST_TASK_STOPPED);
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 res;
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;
}
}