2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
5 * gstpad.c: Pads for linking elements together
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * @short_description: Object contained by elements that allows links to
26 * @see_also: #GstPadTemplate, #GstElement, #GstEvent
28 * A #GstElement is linked to other elements via "pads", which are extremely
29 * light-weight generic link points.
30 * After two pads are retrieved from an element with gst_element_get_pad(),
31 * the pads can be link with gst_pad_link(). (For quick links,
32 * you can also use gst_element_link(), which will make the obvious
33 * link for you if it's straightforward.)
35 * Pads are typically created from a #GstPadTemplate with
36 * gst_pad_new_from_template().
38 * Pads have #GstCaps attached to it to describe the media type they are
39 * capable of dealing with. gst_pad_get_caps() and gst_pad_try_set_caps() are
40 * used to manipulate the caps of the pads.
41 * Pads created from a pad template cannot set capabilities that are
42 * incompatible with the pad template capabilities.
44 * Pads without pad templates can be created with gst_pad_new(),
45 * which takes a direction and a name as an argument. If the name is NULL,
46 * then a guaranteed unique name will be assigned to it.
48 * gst_pad_get_parent() will retrieve the #GstElement that owns the pad.
50 * A #GstElement creating a pad will typically use the various
51 * gst_pad_set_*_function() calls to register callbacks for various events
54 * GstElements will use gst_pad_push() and gst_pad_pull() to push out
55 * or pull in a buffer.
56 * gst_pad_select() and gst_pad_selectv() are used by plugins to wait for the
57 * first incoming buffer or event on any of the given set of pads.
59 * To send a #GstEvent on a pad, use gst_pad_send_event().
61 * Last reviewed on December 13th, 2002 (0.5.0.1)
64 #include "gst_private.h"
67 #include "gstpadtemplate.h"
68 #include "gstenumtypes.h"
69 #include "gstmarshal.h"
74 #include "glib-compat.h"
76 GST_DEBUG_CATEGORY_STATIC (debug_dataflow);
77 #define GST_CAT_DEFAULT GST_CAT_PADS
79 /* Pad signals and args */
99 static void gst_pad_class_init (GstPadClass * klass);
100 static void gst_pad_init (GstPad * pad);
101 static void gst_pad_dispose (GObject * object);
102 static void gst_pad_finalize (GObject * object);
103 static void gst_pad_set_property (GObject * object, guint prop_id,
104 const GValue * value, GParamSpec * pspec);
105 static void gst_pad_get_property (GObject * object, guint prop_id,
106 GValue * value, GParamSpec * pspec);
108 static GstFlowReturn handle_pad_block (GstPad * pad);
109 static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
110 static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
111 static gboolean gst_pad_activate_default (GstPad * pad);
113 #ifndef GST_DISABLE_LOADSAVE
114 static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
117 static GstObjectClass *parent_class = NULL;
118 static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
120 /* quarks for probe signals */
121 static GQuark buffer_quark;
122 static GQuark event_quark;
131 static GstFlowQuarks flow_quarks[] = {
132 {GST_FLOW_RESEND, "resend", 0},
133 {GST_FLOW_OK, "ok", 0},
134 {GST_FLOW_NOT_LINKED, "not-linked", 0},
135 {GST_FLOW_WRONG_STATE, "wrong-state", 0},
136 {GST_FLOW_UNEXPECTED, "unexpected", 0},
137 {GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
138 {GST_FLOW_ERROR, "error", 0},
139 {GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
146 * @ret: a #GstFlowReturn to get the name of.
148 * Gets a string representing the given flow return.
150 * Returns: a string with the name of the flow return.
152 G_CONST_RETURN gchar *
153 gst_flow_get_name (GstFlowReturn ret)
157 for (i = 0; flow_quarks[i].name; i++) {
158 if (ret == flow_quarks[i].ret)
159 return flow_quarks[i].name;
166 * @ret: a #GstFlowReturn to get the quark of.
168 * Get the unique quark for the given GstFlowReturn.
170 * Returns: the quark associated with the flow return or 0 if an
171 * invalid return was specified.
174 gst_flow_to_quark (GstFlowReturn ret)
178 for (i = 0; flow_quarks[i].name; i++) {
179 if (ret == flow_quarks[i].ret)
180 return flow_quarks[i].quark;
186 gst_pad_get_type (void)
188 static GType gst_pad_type = 0;
191 static const GTypeInfo pad_info = {
192 sizeof (GstPadClass), NULL, NULL,
193 (GClassInitFunc) gst_pad_class_init, NULL, NULL,
196 (GInstanceInitFunc) gst_pad_init, NULL
200 gst_pad_type = g_type_register_static (GST_TYPE_OBJECT, "GstPad",
203 buffer_quark = g_quark_from_static_string ("buffer");
204 event_quark = g_quark_from_static_string ("event");
206 for (i = 0; flow_quarks[i].name; i++) {
207 flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name);
210 GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW",
211 GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads");
217 _gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
218 GValue * return_accu, const GValue * handler_return, gpointer dummy)
220 gboolean ret = g_value_get_boolean (handler_return);
222 GST_DEBUG ("accumulated %d", ret);
223 g_value_set_boolean (return_accu, ret);
229 default_have_data (GstPad * pad, GstMiniObject * o)
235 gst_pad_class_init (GstPadClass * klass)
237 GObjectClass *gobject_class;
240 GstObjectClass *gstobject_class;
242 gobject_class = (GObjectClass *) klass;
243 gstobject_class = (GstObjectClass *) klass;
245 parent_class = g_type_class_ref (GST_TYPE_OBJECT);
247 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pad_dispose);
248 gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_pad_finalize);
249 gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pad_set_property);
250 gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pad_get_property);
254 * @pad: the pad that emitted the signal
255 * @peer: the peer pad that has been connected
257 * Signals that a pad has been linked to the peer pad.
259 gst_pad_signals[PAD_LINKED] =
260 g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
261 G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
262 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
265 * @pad: the pad that emitted the signal
266 * @peer: the peer pad that has been disconnected
268 * Signals that a pad has been unlinked from the peer pad.
270 gst_pad_signals[PAD_UNLINKED] =
271 g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
272 G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
273 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
275 * GstPad::request-link:
276 * @pad: the pad that emitted the signal
277 * @peer: the peer pad for which a connection is requested
279 * Signals that a pad connection has been requested.
281 gst_pad_signals[PAD_REQUEST_LINK] =
282 g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
283 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
284 NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
288 * @pad: the pad that emitted the signal
289 * @mini_obj: new data
291 * Signals that new data is available on the pad. This signal is used
292 * internally for implementing pad probes.
293 * See gst_pad_add_*_probe functions.
295 * Returns: %TRUE to keep the data, %FALSE to drop it
297 gst_pad_signals[PAD_HAVE_DATA] =
298 g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
299 G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
300 G_STRUCT_OFFSET (GstPadClass, have_data),
301 _gst_do_pass_data_accumulator,
302 NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
303 GST_TYPE_MINI_OBJECT);
305 g_object_class_install_property (G_OBJECT_CLASS (klass), PAD_PROP_CAPS,
306 g_param_spec_boxed ("caps", "Caps", "The capabilities of the pad",
307 GST_TYPE_CAPS, G_PARAM_READABLE));
308 g_object_class_install_property (G_OBJECT_CLASS (klass), PAD_PROP_DIRECTION,
309 g_param_spec_enum ("direction", "Direction", "The direction of the pad",
310 GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
311 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
312 g_object_class_install_property (G_OBJECT_CLASS (klass), PAD_PROP_TEMPLATE,
313 g_param_spec_object ("template", "Template",
314 "The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
317 #ifndef GST_DISABLE_LOADSAVE
318 gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_pad_save_thyself);
320 gstobject_class->path_string_separator = ".";
322 klass->have_data = default_have_data;
326 gst_pad_init (GstPad * pad)
328 pad->direction = GST_PAD_UNKNOWN;
331 pad->chainfunc = NULL;
335 pad->linkfunc = NULL;
336 pad->getcapsfunc = NULL;
338 pad->activatefunc = GST_DEBUG_FUNCPTR (gst_pad_activate_default);
339 pad->eventfunc = GST_DEBUG_FUNCPTR (gst_pad_event_default);
340 pad->querytypefunc = GST_DEBUG_FUNCPTR (gst_pad_get_query_types_default);
341 pad->queryfunc = GST_DEBUG_FUNCPTR (gst_pad_query_default);
342 pad->intlinkfunc = GST_DEBUG_FUNCPTR (gst_pad_get_internal_links_default);
344 pad->do_buffer_signals = 0;
345 pad->do_event_signals = 0;
347 GST_PAD_UNSET_FLUSHING (pad);
349 pad->preroll_lock = g_mutex_new ();
350 pad->preroll_cond = g_cond_new ();
352 pad->stream_rec_lock = g_new (GStaticRecMutex, 1);
353 g_static_rec_mutex_init (pad->stream_rec_lock);
355 pad->block_cond = g_cond_new ();
359 gst_pad_dispose (GObject * object)
361 GstPad *pad = GST_PAD (object);
363 GST_CAT_DEBUG (GST_CAT_REFCOUNTING, "dispose %s:%s",
364 GST_DEBUG_PAD_NAME (pad));
366 /* we don't hold a ref to the peer so we can just set the
368 GST_PAD_PEER (pad) = NULL;
371 gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
373 gst_pad_set_pad_template (pad, NULL);
375 G_OBJECT_CLASS (parent_class)->dispose (object);
379 gst_pad_finalize (GObject * object)
381 GstPad *pad = GST_PAD (object);
384 /* in case the task is still around, clean it up */
385 if ((task = GST_PAD_TASK (pad))) {
386 gst_task_join (task);
387 GST_PAD_TASK (pad) = NULL;
388 gst_object_unref (task);
391 if (pad->stream_rec_lock) {
392 g_static_rec_mutex_free (pad->stream_rec_lock);
393 g_free (pad->stream_rec_lock);
394 pad->stream_rec_lock = NULL;
396 if (pad->preroll_lock) {
397 g_mutex_free (pad->preroll_lock);
398 g_cond_free (pad->preroll_cond);
399 pad->preroll_lock = NULL;
400 pad->preroll_cond = NULL;
402 if (pad->block_cond) {
403 g_cond_free (pad->block_cond);
404 pad->block_cond = NULL;
407 G_OBJECT_CLASS (parent_class)->finalize (object);
411 gst_pad_set_property (GObject * object, guint prop_id,
412 const GValue * value, GParamSpec * pspec)
414 g_return_if_fail (GST_IS_PAD (object));
417 case PAD_PROP_DIRECTION:
418 GST_PAD_DIRECTION (object) = g_value_get_enum (value);
420 case PAD_PROP_TEMPLATE:
421 gst_pad_set_pad_template (GST_PAD_CAST (object),
422 (GstPadTemplate *) g_value_dup_gst_object (value));
425 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
431 gst_pad_get_property (GObject * object, guint prop_id,
432 GValue * value, GParamSpec * pspec)
434 g_return_if_fail (GST_IS_PAD (object));
438 g_value_set_boxed (value, GST_PAD_CAPS (object));
440 case PAD_PROP_DIRECTION:
441 g_value_set_enum (value, GST_PAD_DIRECTION (object));
443 case PAD_PROP_TEMPLATE:
444 g_value_set_object (value, GST_PAD_PAD_TEMPLATE (object));
447 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
454 * @name: the name of the new pad.
455 * @direction: the #GstPadDirection of the pad.
457 * Creates a new pad with the given name in the given direction.
458 * If name is NULL, a guaranteed unique name (across all pads)
460 * This function makes a copy of the name so you can safely free the name.
462 * Returns: a new #GstPad, or NULL in case of an error.
467 gst_pad_new (const gchar * name, GstPadDirection direction)
469 return g_object_new (GST_TYPE_PAD,
470 "name", name, "direction", direction, NULL);
474 * gst_pad_new_from_template:
475 * @templ: the pad template to use
476 * @name: the name of the element
478 * Creates a new pad with the given name from the given template.
479 * If name is NULL, a guaranteed unique name (across all pads)
481 * This function makes a copy of the name so you can safely free the name.
483 * Returns: a new #GstPad, or NULL in case of an error.
486 gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
488 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
490 return g_object_new (GST_TYPE_PAD,
491 "name", name, "direction", templ->direction, "template", templ, NULL);
495 * gst_pad_get_direction:
496 * @pad: a #GstPad to get the direction of.
498 * Gets the direction of the pad. The direction of the pad is
499 * decided at construction time so this function does not take
502 * Returns: the #GstPadDirection of the pad.
507 gst_pad_get_direction (GstPad * pad)
509 GstPadDirection result;
511 /* PAD_UNKNOWN is a little silly but we need some sort of
512 * error return value */
513 g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
516 result = GST_PAD_DIRECTION (pad);
523 gst_pad_activate_default (GstPad * pad)
525 return gst_pad_activate_push (pad, TRUE);
529 pre_activate (GstPad * pad, GstActivateMode new_mode)
532 case GST_ACTIVATE_PUSH:
533 case GST_ACTIVATE_PULL:
535 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d, unset flushing",
537 GST_PAD_UNSET_FLUSHING (pad);
538 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
541 case GST_ACTIVATE_NONE:
543 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE NONE, set flushing",
545 GST_PAD_SET_FLUSHING (pad);
546 /* unlock blocked pads so element can resume and stop */
547 GST_PAD_BLOCK_SIGNAL (pad);
554 post_activate (GstPad * pad, GstActivateMode new_mode)
557 case GST_ACTIVATE_PUSH:
558 case GST_ACTIVATE_PULL:
561 case GST_ACTIVATE_NONE:
562 /* ensures that streaming stops */
563 GST_STREAM_LOCK (pad);
564 /* while we're at it set activation mode */
566 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d", new_mode);
567 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
569 GST_STREAM_UNLOCK (pad);
575 * gst_pad_set_active:
576 * @pad: the #GstPad to activate or deactivate.
577 * @active: whether or not the pad should be active.
579 * Activates or deactivates the given pad.
580 * Normally called from within core state change functions.
582 * If @active, makes sure the pad is active. If it is already active, either in
583 * push or pull mode, just return. Otherwise dispatches to the pad's activate
584 * function to perform the actual activation.
586 * If not @active, checks the pad's current mode and calls
587 * gst_pad_activate_push() or gst_pad_activate_pull(), as appropriate, with a
590 * Returns: #TRUE if the operation was successful.
595 gst_pad_set_active (GstPad * pad, gboolean active)
598 gboolean ret = FALSE;
600 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
603 old = GST_PAD_ACTIVATE_MODE (pad);
608 case GST_ACTIVATE_PUSH:
609 case GST_ACTIVATE_PULL:
612 case GST_ACTIVATE_NONE:
613 ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
618 case GST_ACTIVATE_PUSH:
619 ret = gst_pad_activate_push (pad, FALSE);
621 case GST_ACTIVATE_PULL:
622 ret = gst_pad_activate_pull (pad, FALSE);
624 case GST_ACTIVATE_NONE:
630 if (!active && !ret) {
632 g_critical ("Failed to deactivate pad %s:%s, very bad",
633 GST_DEBUG_PAD_NAME (pad));
641 * gst_pad_activate_pull:
642 * @pad: the #GstPad to activate or deactivate.
643 * @active: whether or not the pad should be active.
645 * Activates or deactivates the given pad in pull mode via dispatching to the
646 * pad's activatepullfunc. For use from within pad activation functions only.
647 * When called on sink pads, will first proxy the call to the peer pad, which is
648 * expected to activate its internally linked pads from within its activate_pull
651 * If you don't know what this is, you probably don't want to call it.
653 * Returns: TRUE if the operation was successfull.
658 gst_pad_activate_pull (GstPad * pad, gboolean active)
660 GstActivateMode old, new;
663 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
666 old = GST_PAD_ACTIVATE_MODE (pad);
669 if ((active && old == GST_ACTIVATE_PULL)
670 || (!active && old == GST_ACTIVATE_NONE))
674 g_return_val_if_fail (old == GST_ACTIVATE_NONE, FALSE);
676 g_return_val_if_fail (old == GST_ACTIVATE_PULL, FALSE);
679 if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
680 if ((peer = gst_pad_get_peer (pad))) {
681 if (!gst_pad_activate_pull (peer, active))
683 gst_object_unref (peer);
687 new = active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
688 pre_activate (pad, new);
690 if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
691 if (!GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active))
694 /* can happen for sinks of passthrough elements */
697 post_activate (pad, new);
699 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
700 active ? "activated" : "deactivated");
705 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
706 active ? "activated" : "deactivated");
712 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
713 "activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
715 gst_object_unref (peer);
720 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
721 active ? "activate" : "deactivate");
722 pre_activate (pad, GST_ACTIVATE_NONE);
723 post_activate (pad, GST_ACTIVATE_NONE);
729 * gst_pad_activate_push:
730 * @pad: the #GstPad to activate or deactivate.
731 * @active: whether or not the pad should be active.
733 * Activates or deactivates the given pad in push mode via dispatching to the
734 * pad's activatepushfunc. For use from within pad activation functions only.
736 * If you don't know what this is, you probably don't want to call it.
738 * Returns: TRUE if the operation was successfull.
743 gst_pad_activate_push (GstPad * pad, gboolean active)
745 GstActivateMode old, new;
747 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
748 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
749 active ? "activated" : "deactivated");
752 old = GST_PAD_ACTIVATE_MODE (pad);
755 if ((active && old == GST_ACTIVATE_PUSH)
756 || (!active && old == GST_ACTIVATE_NONE))
760 g_return_val_if_fail (old == GST_ACTIVATE_NONE, FALSE);
762 g_return_val_if_fail (old == GST_ACTIVATE_PUSH, FALSE);
765 new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
766 pre_activate (pad, new);
768 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
769 if (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active)) {
773 /* quite ok, element relies on state change func to prepare itself */
776 post_activate (pad, new);
778 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
779 active ? "activated" : "deactivated");
784 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
785 active ? "activated" : "deactivated");
790 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
791 active ? "activate" : "deactivate");
792 pre_activate (pad, GST_ACTIVATE_NONE);
793 post_activate (pad, GST_ACTIVATE_NONE);
800 * @pad: the #GstPad to query
802 * Query if a pad is active
804 * Returns: TRUE if the pad is active.
809 gst_pad_is_active (GstPad * pad)
811 gboolean result = FALSE;
813 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
816 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
823 * gst_pad_set_blocked_async:
824 * @pad: the #GstPad to block or unblock
825 * @blocked: boolean indicating whether the pad should be blocked or unblocked
826 * @callback: #GstPadBlockCallback that will be called when the
828 * @user_data: user data passed to the callback
830 * Blocks or unblocks the dataflow on a pad. The provided callback
831 * is called when the operation succeeds; this happens right before the next
832 * attempt at pushing a buffer on the pad.
834 * This can take a while as the pad can only become blocked when real dataflow
836 * When the pipeline is stalled, for example in PAUSED, this can
837 * take an indeterminate amount of time.
838 * You can pass NULL as the callback to make this call block. Be careful with
839 * this blocking call as it might not return for reasons stated above.
841 * Returns: TRUE if the pad could be blocked. This function can fail
842 * if wrong parameters were passed or the pad was already in the
848 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
849 GstPadBlockCallback callback, gpointer user_data)
851 gboolean was_blocked;
853 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
857 was_blocked = GST_PAD_IS_BLOCKED (pad);
859 if (G_UNLIKELY (was_blocked == blocked))
860 goto had_right_state;
863 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad %s:%s",
864 GST_DEBUG_PAD_NAME (pad));
866 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
867 pad->block_callback = callback;
868 pad->block_data = user_data;
870 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
871 GST_PAD_BLOCK_WAIT (pad);
872 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
875 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad %s:%s",
876 GST_DEBUG_PAD_NAME (pad));
878 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
880 pad->block_callback = callback;
881 pad->block_data = user_data;
884 GST_PAD_BLOCK_SIGNAL (pad);
886 GST_PAD_BLOCK_SIGNAL (pad);
887 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
888 GST_PAD_BLOCK_WAIT (pad);
889 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
898 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
899 "pad %s:%s was in right state", GST_DEBUG_PAD_NAME (pad));
906 * gst_pad_set_blocked:
907 * @pad: the #GstPad to block or unblock
908 * @blocked: boolean indicating we should block or unblock
910 * Blocks or unblocks the dataflow on a pad. This function is
911 * a shortcut for gst_pad_set_blocked_async() with a NULL
914 * Returns: TRUE if the pad could be blocked. This function can fail
915 * wrong parameters were passed or the pad was already in the
921 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
923 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
927 * gst_pad_is_blocked:
928 * @pad: the #GstPad to query
930 * Checks if the pad is blocked or not. This function returns the
931 * last requested state of the pad. It is not certain that the pad
932 * is actually blocked at this point.
934 * Returns: TRUE if the pad is blocked.
939 gst_pad_is_blocked (GstPad * pad)
941 gboolean result = FALSE;
943 g_return_val_if_fail (GST_IS_PAD (pad), result);
946 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
953 * gst_pad_set_activate_function:
954 * @pad: a sink #GstPad.
955 * @activate: the #GstPadActivateFunction to set.
957 * Sets the given activate function for the pad. The activate function will
958 * dispatch to activate_push or activate_pull to perform the actual activation.
959 * Only makes sense to set on sink pads.
961 * Call this function if your sink pad can start a pull-based task.
964 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
966 g_return_if_fail (GST_IS_PAD (pad));
968 GST_PAD_ACTIVATEFUNC (pad) = activate;
969 GST_CAT_DEBUG (GST_CAT_PADS, "activatefunc for %s:%s set to %s",
970 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activate));
974 * gst_pad_set_activatepull_function:
975 * @pad: a sink #GstPad.
976 * @activatepull: the #GstPadActivateModeFunction to set.
978 * Sets the given activate_pull function for the pad. An activate_pull function
979 * prepares the element and any upstream connections for pulling. See XXX
980 * part-activation.txt for details.
983 gst_pad_set_activatepull_function (GstPad * pad,
984 GstPadActivateModeFunction activatepull)
986 g_return_if_fail (GST_IS_PAD (pad));
988 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
989 GST_CAT_DEBUG (GST_CAT_PADS, "activatepullfunc for %s:%s set to %s",
990 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activatepull));
994 * gst_pad_set_activatepush_function:
995 * @pad: a sink #GstPad.
996 * @activatepush: the #GstPadActivateModeFunction to set.
998 * Sets the given activate_push function for the pad. An activate_push function
999 * prepares the element for pushing. See XXX part-activation.txt for details.
1002 gst_pad_set_activatepush_function (GstPad * pad,
1003 GstPadActivateModeFunction activatepush)
1005 g_return_if_fail (GST_IS_PAD (pad));
1007 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1008 GST_CAT_DEBUG (GST_CAT_PADS, "activatepushfunc for %s:%s set to %s",
1009 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activatepush));
1013 * gst_pad_set_chain_function:
1014 * @pad: a sink #GstPad.
1015 * @chain: the #GstPadChainFunction to set.
1017 * Sets the given chain function for the pad. The chain function is called to
1018 * process a #GstBuffer input buffer.
1021 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1023 g_return_if_fail (GST_IS_PAD (pad));
1024 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
1026 GST_PAD_CHAINFUNC (pad) = chain;
1027 GST_CAT_DEBUG (GST_CAT_PADS, "chainfunc for %s:%s set to %s",
1028 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (chain));
1032 * gst_pad_set_getrange_function:
1033 * @pad: a source #GstPad.
1034 * @get: the #GstPadGetRangeFunction to set.
1036 * Sets the given getrange function for the pad. The getrange function is called to
1037 * produce a new #GstBuffer to start the processing pipeline. Getrange functions cannot
1041 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1043 g_return_if_fail (GST_IS_PAD (pad));
1044 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1046 GST_PAD_GETRANGEFUNC (pad) = get;
1048 GST_CAT_DEBUG (GST_CAT_PADS, "getrangefunc for %s:%s set to %s",
1049 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (get));
1053 * gst_pad_set_checkgetrange_function:
1054 * @pad: a source #GstPad.
1055 * @check: the #GstPadCheckGetRangeFunction to set.
1057 * Sets the given checkgetrange function for the pad. Implement this function on
1058 * a pad if you dynamically support getrange based scheduling on the pad.
1061 gst_pad_set_checkgetrange_function (GstPad * pad,
1062 GstPadCheckGetRangeFunction check)
1064 g_return_if_fail (GST_IS_PAD (pad));
1065 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1067 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1069 GST_CAT_DEBUG (GST_CAT_PADS, "checkgetrangefunc for %s:%s set to %s",
1070 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (check));
1074 * gst_pad_set_event_function:
1075 * @pad: a source #GstPad.
1076 * @event: the #GstPadEventFunction to set.
1078 * Sets the given event handler for the pad.
1081 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1083 g_return_if_fail (GST_IS_PAD (pad));
1085 GST_PAD_EVENTFUNC (pad) = event;
1087 GST_CAT_DEBUG (GST_CAT_PADS, "eventfunc for %s:%s set to %s",
1088 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (event));
1092 * gst_pad_set_query_function:
1093 * @pad: a #GstPad of either direction.
1094 * @query: the #GstPadQueryFunction to set.
1096 * Set the given query function for the pad.
1099 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1101 g_return_if_fail (GST_IS_PAD (pad));
1103 GST_PAD_QUERYFUNC (pad) = query;
1105 GST_CAT_DEBUG (GST_CAT_PADS, "queryfunc for %s:%s set to %s",
1106 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (query));
1110 * gst_pad_set_query_type_function:
1111 * @pad: a #GstPad of either direction.
1112 * @type_func: the #GstPadQueryTypeFunction to set.
1114 * Set the given query type function for the pad.
1117 gst_pad_set_query_type_function (GstPad * pad,
1118 GstPadQueryTypeFunction type_func)
1120 g_return_if_fail (GST_IS_PAD (pad));
1122 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1124 GST_CAT_DEBUG (GST_CAT_PADS, "querytypefunc for %s:%s set to %s",
1125 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (type_func));
1129 * gst_pad_get_query_types:
1132 * Get an array of supported queries that can be performed
1135 * Returns: a zero-terminated array of #GstQueryType.
1137 const GstQueryType *
1138 gst_pad_get_query_types (GstPad * pad)
1140 GstPadQueryTypeFunction func;
1142 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1144 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1156 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1158 *data = gst_pad_get_query_types (pad);
1164 * gst_pad_get_query_types_default:
1167 * Invoke the default dispatcher for the query types on
1170 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1171 * internally-linked pads has a query types function.
1173 const GstQueryType *
1174 gst_pad_get_query_types_default (GstPad * pad)
1176 GstQueryType *result = NULL;
1178 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1180 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1181 gst_pad_get_query_types_dispatcher, &result);
1187 * gst_pad_set_internal_link_function:
1188 * @pad: a #GstPad of either direction.
1189 * @intlink: the #GstPadIntLinkFunction to set.
1191 * Sets the given internal link function for the pad.
1194 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1196 g_return_if_fail (GST_IS_PAD (pad));
1198 GST_PAD_INTLINKFUNC (pad) = intlink;
1199 GST_CAT_DEBUG (GST_CAT_PADS, "internal link for %s:%s set to %s",
1200 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (intlink));
1204 * gst_pad_set_link_function:
1206 * @link: the #GstPadLinkFunction to set.
1208 * Sets the given link function for the pad. It will be called when
1209 * the pad is linked with another pad.
1211 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1214 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1215 * cannot be made for some reason.
1217 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1218 * of the peer sink pad, if present.
1221 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1223 g_return_if_fail (GST_IS_PAD (pad));
1225 GST_PAD_LINKFUNC (pad) = link;
1226 GST_CAT_DEBUG (GST_CAT_PADS, "linkfunc for %s:%s set to %s",
1227 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (link));
1231 * gst_pad_set_unlink_function:
1233 * @unlink: the #GstPadUnlinkFunction to set.
1235 * Sets the given unlink function for the pad. It will be called
1236 * when the pad is unlinked.
1239 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1241 g_return_if_fail (GST_IS_PAD (pad));
1243 GST_PAD_UNLINKFUNC (pad) = unlink;
1244 GST_CAT_DEBUG (GST_CAT_PADS, "unlinkfunc for %s:%s set to %s",
1245 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (unlink));
1249 * gst_pad_set_getcaps_function:
1251 * @getcaps: the #GstPadGetCapsFunction to set.
1253 * Sets the given getcaps function for the pad. @getcaps should return the
1254 * allowable caps for a pad in the context of the element's state, its link to
1255 * other elements, and the devices or files it has opened. These caps must be a
1256 * subset of the pad template caps. In the NULL state with no links, @getcaps
1257 * should ideally return the same caps as the pad template. In rare
1258 * circumstances, an object property can affect the caps returned by @getcaps,
1259 * but this is discouraged.
1261 * You do not need to call this function if @pad's allowed caps are always the
1262 * same as the pad template caps. This can only be true if the padtemplate
1263 * has fixed simple caps.
1265 * For most filters, the caps returned by @getcaps is directly affected by the
1266 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1267 * the srcpad's getcaps function is directly related to the stream data. Again,
1268 * @getcaps should return the most specific caps it reasonably can, since this
1269 * helps with autoplugging.
1271 * Note that the return value from @getcaps is owned by the caller, so the caller
1272 * should unref the caps after usage.
1275 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1277 g_return_if_fail (GST_IS_PAD (pad));
1279 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1280 GST_CAT_DEBUG (GST_CAT_PADS, "getcapsfunc for %s:%s set to %s",
1281 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (getcaps));
1285 * gst_pad_set_acceptcaps_function:
1287 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1289 * Sets the given acceptcaps function for the pad. The acceptcaps function
1290 * will be called to check if the pad can accept the given caps.
1293 gst_pad_set_acceptcaps_function (GstPad * pad,
1294 GstPadAcceptCapsFunction acceptcaps)
1296 g_return_if_fail (GST_IS_PAD (pad));
1298 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1299 GST_CAT_DEBUG (GST_CAT_PADS, "acceptcapsfunc for %s:%s set to %s",
1300 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1304 * gst_pad_set_fixatecaps_function:
1306 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1308 * Sets the given fixatecaps function for the pad. The fixatecaps function
1309 * will be called whenever the default values for a GstCaps needs to be
1313 gst_pad_set_fixatecaps_function (GstPad * pad,
1314 GstPadFixateCapsFunction fixatecaps)
1316 g_return_if_fail (GST_IS_PAD (pad));
1318 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1319 GST_CAT_DEBUG (GST_CAT_PADS, "fixatecapsfunc for %s:%s set to %s",
1320 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1324 * gst_pad_set_setcaps_function:
1326 * @setcaps: the #GstPadSetCapsFunction to set.
1328 * Sets the given setcaps function for the pad. The setcaps function
1329 * will be called whenever a buffer with a new media type is pushed or
1330 * pulled from the pad. The pad/element needs to update it's internal
1331 * structures to process the new media type. If this new type is not
1332 * acceptable, the setcaps function should return FALSE.
1335 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1337 g_return_if_fail (GST_IS_PAD (pad));
1339 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1340 GST_CAT_DEBUG (GST_CAT_PADS, "setcapsfunc for %s:%s set to %s",
1341 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (setcaps));
1345 * gst_pad_set_bufferalloc_function:
1346 * @pad: a sink #GstPad.
1347 * @bufalloc: the #GstPadBufferAllocFunction to set.
1349 * Sets the given bufferalloc function for the pad. Note that the
1350 * bufferalloc function can only be set on sinkpads.
1353 gst_pad_set_bufferalloc_function (GstPad * pad,
1354 GstPadBufferAllocFunction bufalloc)
1356 g_return_if_fail (GST_IS_PAD (pad));
1357 g_return_if_fail (GST_PAD_IS_SINK (pad));
1359 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1360 GST_CAT_DEBUG (GST_CAT_PADS, "bufferallocfunc for %s:%s set to %s",
1361 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (bufalloc));
1366 * @srcpad: the source #GstPad to unlink.
1367 * @sinkpad: the sink #GstPad to unlink.
1369 * Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
1372 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1373 * the pads were not linked together.
1378 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1380 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1381 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1383 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1384 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1385 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1389 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1394 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1397 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1398 goto not_linked_together;
1400 if (GST_PAD_UNLINKFUNC (srcpad)) {
1401 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1403 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1404 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1407 /* first clear peers */
1408 GST_PAD_PEER (srcpad) = NULL;
1409 GST_PAD_PEER (sinkpad) = NULL;
1411 GST_UNLOCK (sinkpad);
1412 GST_UNLOCK (srcpad);
1414 /* fire off a signal to each of the pads telling them
1415 * that they've been unlinked */
1416 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1417 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1419 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1420 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1426 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1427 GST_UNLOCK (srcpad);
1432 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1433 GST_UNLOCK (sinkpad);
1434 GST_UNLOCK (srcpad);
1437 not_linked_together:
1439 /* we do not emit a warning in this case because unlinking cannot
1440 * be made MT safe.*/
1441 GST_UNLOCK (sinkpad);
1442 GST_UNLOCK (srcpad);
1448 * gst_pad_is_linked:
1449 * @pad: pad to check
1451 * Checks if a @pad is linked to another pad or not.
1453 * Returns: TRUE if the pad is linked, FALSE otherwise.
1458 gst_pad_is_linked (GstPad * pad)
1462 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1465 result = (GST_PAD_PEER (pad) != NULL);
1471 /* get the caps from both pads and see if the intersection
1474 * This function should be called with the pad LOCK on both
1478 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1483 srccaps = gst_pad_get_caps_unlocked (src);
1484 sinkcaps = gst_pad_get_caps_unlocked (sink);
1485 GST_CAT_DEBUG (GST_CAT_CAPS, "src caps %" GST_PTR_FORMAT, srccaps);
1486 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1488 /* if we have caps on both pads we can check the intersection */
1489 if (srccaps && sinkcaps) {
1492 icaps = gst_caps_intersect (srccaps, sinkcaps);
1493 gst_caps_unref (srccaps);
1494 gst_caps_unref (sinkcaps);
1496 GST_CAT_DEBUG (GST_CAT_CAPS,
1497 "intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
1499 if (!icaps || gst_caps_is_empty (icaps)) {
1500 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is empty");
1501 gst_caps_unref (icaps);
1504 gst_caps_unref (icaps);
1510 /* check if the grandparents of both pads are the same.
1511 * This check is required so that we don't try to link
1512 * pads from elements in different bins without ghostpads.
1514 * The LOCK should be helt on both pads
1517 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1519 GstObject *psrc, *psink;
1520 gboolean res = TRUE;
1522 psrc = GST_OBJECT_PARENT (src);
1523 psink = GST_OBJECT_PARENT (sink);
1525 /* if one of the pads has no parent, we allow the link */
1526 if (psrc && psink) {
1527 /* if the parents are the same, we have a loop */
1528 if (psrc == psink) {
1529 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1534 /* if they both have a parent, we check the grandparents */
1535 psrc = gst_object_get_parent (psrc);
1536 psink = gst_object_get_parent (psink);
1538 if (psrc != psink) {
1539 /* if they have grandparents but they are not the same */
1540 GST_CAT_DEBUG (GST_CAT_CAPS,
1541 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1542 GST_PTR_FORMAT, psrc, psink);
1546 gst_object_unref (psrc);
1548 gst_object_unref (psink);
1554 /* FIXME leftover from an attempt at refactoring... */
1555 /* call with the two pads unlocked */
1556 static GstPadLinkReturn
1557 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1559 /* generic checks */
1560 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
1561 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
1563 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1564 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1568 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1571 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1572 goto src_was_linked;
1576 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1579 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1580 goto sink_was_linked;
1582 /* check hierarchy, pads can only be linked if the grandparents
1584 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1585 goto wrong_hierarchy;
1587 /* check pad caps for non-empty intersection */
1588 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1591 /* FIXME check pad scheduling for non-empty intersection */
1593 return GST_PAD_LINK_OK;
1597 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1598 GST_UNLOCK (srcpad);
1599 return GST_PAD_LINK_WRONG_DIRECTION;
1603 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was linked",
1604 GST_DEBUG_PAD_NAME (srcpad));
1605 /* we do not emit a warning in this case because unlinking cannot
1606 * be made MT safe.*/
1607 GST_UNLOCK (srcpad);
1608 return GST_PAD_LINK_WAS_LINKED;
1612 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1613 GST_UNLOCK (sinkpad);
1614 GST_UNLOCK (srcpad);
1615 return GST_PAD_LINK_WRONG_DIRECTION;
1619 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was linked",
1620 GST_DEBUG_PAD_NAME (sinkpad));
1621 /* we do not emit a warning in this case because unlinking cannot
1622 * be made MT safe.*/
1623 GST_UNLOCK (sinkpad);
1624 GST_UNLOCK (srcpad);
1625 return GST_PAD_LINK_WAS_LINKED;
1629 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1630 GST_UNLOCK (sinkpad);
1631 GST_UNLOCK (srcpad);
1632 return GST_PAD_LINK_WRONG_HIERARCHY;
1636 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1637 GST_UNLOCK (sinkpad);
1638 GST_UNLOCK (srcpad);
1639 return GST_PAD_LINK_NOFORMAT;
1645 * @srcpad: the source #GstPad to link.
1646 * @sinkpad: the sink #GstPad to link.
1648 * Links the source pad and the sink pad.
1650 * Returns: A result code indicating if the connection worked or
1656 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1658 GstPadLinkReturn result;
1660 /* prepare will also lock the two pads */
1661 result = gst_pad_link_prepare (srcpad, sinkpad);
1663 if (result != GST_PAD_LINK_OK)
1664 goto prepare_failed;
1666 GST_UNLOCK (sinkpad);
1667 GST_UNLOCK (srcpad);
1669 /* FIXME released the locks here, concurrent thread might link
1670 * something else. */
1671 if (GST_PAD_LINKFUNC (srcpad)) {
1672 /* this one will call the peer link function */
1673 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
1674 } else if (GST_PAD_LINKFUNC (sinkpad)) {
1675 /* if no source link function, we need to call the sink link
1676 * function ourselves. */
1677 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
1679 result = GST_PAD_LINK_OK;
1685 if (result == GST_PAD_LINK_OK) {
1686 GST_PAD_PEER (srcpad) = sinkpad;
1687 GST_PAD_PEER (sinkpad) = srcpad;
1689 GST_UNLOCK (sinkpad);
1690 GST_UNLOCK (srcpad);
1692 /* fire off a signal to each of the pads telling them
1693 * that they've been linked */
1694 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
1695 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
1697 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
1698 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1700 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
1701 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1703 GST_UNLOCK (sinkpad);
1704 GST_UNLOCK (srcpad);
1715 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
1717 /* this function would need checks if it weren't static */
1720 gst_object_replace ((GstObject **) & pad->padtemplate, (GstObject *) templ);
1724 gst_pad_template_pad_created (templ, pad);
1728 * gst_pad_get_pad_template:
1731 * Gets the template for @pad.
1733 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
1734 * if this pad has no template.
1736 * FIXME: currently returns an unrefcounted padtemplate.
1739 gst_pad_get_pad_template (GstPad * pad)
1741 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1743 return GST_PAD_PAD_TEMPLATE (pad);
1747 /* should be called with the pad LOCK held */
1748 /* refs the caps, so caller is responsible for getting it unreffed */
1750 gst_pad_get_caps_unlocked (GstPad * pad)
1752 GstCaps *result = NULL;
1754 GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
1755 GST_DEBUG_PAD_NAME (pad), pad);
1757 if (GST_PAD_GETCAPSFUNC (pad)) {
1758 GST_CAT_DEBUG (GST_CAT_CAPS, "dispatching to pad getcaps function");
1760 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
1762 result = GST_PAD_GETCAPSFUNC (pad) (pad);
1764 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
1766 if (result == NULL) {
1767 g_critical ("pad %s:%s returned NULL caps from getcaps function",
1768 GST_DEBUG_PAD_NAME (pad));
1770 GST_CAT_DEBUG (GST_CAT_CAPS,
1771 "pad getcaps %s:%s returned %" GST_PTR_FORMAT,
1772 GST_DEBUG_PAD_NAME (pad), result);
1773 #ifndef G_DISABLE_ASSERT
1774 /* check that the returned caps are a real subset of the template caps */
1775 if (GST_PAD_PAD_TEMPLATE (pad)) {
1776 const GstCaps *templ_caps =
1777 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
1778 if (!gst_caps_is_subset (result, templ_caps)) {
1781 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
1782 "pad returned caps %" GST_PTR_FORMAT
1783 " which are not a real subset of its template caps %"
1784 GST_PTR_FORMAT, result, templ_caps);
1786 ("pad %s:%s returned caps that are not a real subset of its template caps",
1787 GST_DEBUG_PAD_NAME (pad));
1788 temp = gst_caps_intersect (templ_caps, result);
1789 gst_caps_unref (result);
1797 if (GST_PAD_PAD_TEMPLATE (pad)) {
1798 GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
1800 result = GST_PAD_TEMPLATE_CAPS (templ);
1801 GST_CAT_DEBUG (GST_CAT_CAPS,
1802 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
1805 result = gst_caps_ref (result);
1808 if (GST_PAD_CAPS (pad)) {
1809 result = GST_PAD_CAPS (pad);
1811 GST_CAT_DEBUG (GST_CAT_CAPS,
1812 "using pad caps %p %" GST_PTR_FORMAT, result, result);
1814 result = gst_caps_ref (result);
1818 GST_CAT_DEBUG (GST_CAT_CAPS, "pad has no caps");
1819 result = gst_caps_new_empty ();
1827 * @pad: a #GstPad to get the capabilities of.
1829 * Gets the capabilities this pad can produce or consume.
1830 * Note that this method doesn't necessarily returns the caps set by
1831 * #gst_pad_set_caps - use #GST_PAD_CAPS for that instead.
1832 * gst_pad_get_caps returns all possible caps a pad can operate with, using
1833 * the pad's get_caps function;
1834 * this returns the pad template caps if not explicitly set.
1836 * Returns: a newly allocated copy of the #GstCaps of this pad.
1841 gst_pad_get_caps (GstPad * pad)
1843 GstCaps *result = NULL;
1845 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1849 GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
1850 GST_DEBUG_PAD_NAME (pad), pad);
1852 result = gst_pad_get_caps_unlocked (pad);
1859 * gst_pad_peer_get_caps:
1860 * @pad: a #GstPad to get the peer capabilities of.
1862 * Gets the capabilities of the peer connected to this pad.
1864 * Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
1865 * gst_caps_unref to get rid of it. this function returns NULL if there is no
1869 gst_pad_peer_get_caps (GstPad * pad)
1872 GstCaps *result = NULL;
1874 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1878 GST_CAT_DEBUG (GST_CAT_CAPS, "get peer caps of %s:%s (%p)",
1879 GST_DEBUG_PAD_NAME (pad), pad);
1881 peerpad = GST_PAD_PEER (pad);
1882 if (G_UNLIKELY (peerpad == NULL))
1885 gst_object_ref (peerpad);
1888 result = gst_pad_get_caps (peerpad);
1890 gst_object_unref (peerpad);
1902 fixate_value (GValue * dest, const GValue * src)
1904 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
1905 g_value_init (dest, G_TYPE_INT);
1906 g_value_set_int (dest, gst_value_get_int_range_min (src));
1907 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
1908 g_value_init (dest, G_TYPE_DOUBLE);
1909 g_value_set_double (dest, gst_value_get_double_range_min (src));
1910 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
1911 GValue temp = { 0 };
1913 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
1914 if (!fixate_value (dest, &temp))
1915 gst_value_init_and_copy (dest, &temp);
1916 g_value_unset (&temp);
1917 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
1918 gboolean res = FALSE;
1921 g_value_init (dest, GST_TYPE_ARRAY);
1922 for (n = 0; n < gst_value_list_get_size (src); n++) {
1924 const GValue *orig_kid = gst_value_list_get_value (src, n);
1926 if (!fixate_value (&kid, orig_kid))
1927 gst_value_init_and_copy (&kid, orig_kid);
1930 gst_value_list_append_value (dest, &kid);
1931 g_value_unset (&kid);
1935 g_value_unset (dest);
1946 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
1948 GstStructure *s = data;
1951 if (fixate_value (&v, value)) {
1952 gst_structure_id_set_value (s, field_id, &v);
1960 * gst_pad_fixate_caps:
1961 * @pad: a #GstPad to fixate
1962 * @caps: the #GstCaps to fixate
1964 * Fixate a caps on the given pad. Modifies the caps in place, so you should
1965 * make sure that the caps are actually writable (see gst_caps_make_writable()).
1968 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
1970 GstPadFixateCapsFunction fixatefunc;
1973 g_return_if_fail (GST_IS_PAD (pad));
1974 g_return_if_fail (caps != NULL);
1976 if (gst_caps_is_fixed (caps))
1979 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
1981 fixatefunc (pad, caps);
1984 /* default fixation */
1985 for (n = 0; n < gst_caps_get_size (caps); n++) {
1986 GstStructure *s = gst_caps_get_structure (caps, n);
1988 gst_structure_foreach (s, gst_pad_default_fixate, s);
1993 * gst_pad_accept_caps:
1994 * @pad: a #GstPad to check
1995 * @caps: a #GstCaps to check on the pad
1997 * Check if the given pad accepts the caps.
1999 * Returns: TRUE if the pad can accept the caps.
2002 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2005 GstPadAcceptCapsFunction acceptfunc;
2007 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2009 /* any pad can be unnegotiated */
2014 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2016 GST_CAT_DEBUG (GST_CAT_CAPS, "pad accept caps of %s:%s (%p)",
2017 GST_DEBUG_PAD_NAME (pad), pad);
2021 /* we can call the function */
2022 result = acceptfunc (pad, caps);
2024 /* else see get the caps and see if it intersects to something
2029 allowed = gst_pad_get_caps (pad);
2031 intersect = gst_caps_intersect (allowed, caps);
2033 result = !gst_caps_is_empty (intersect);
2035 gst_caps_unref (allowed);
2036 gst_caps_unref (intersect);
2045 * gst_pad_peer_accept_caps:
2046 * @pad: a #GstPad to check
2047 * @caps: a #GstCaps to check on the pad
2049 * Check if the given pad accepts the caps.
2051 * Returns: TRUE if the pad can accept the caps.
2054 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2059 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2063 GST_CAT_DEBUG (GST_CAT_CAPS, "peer accept caps of %s:%s (%p)",
2064 GST_DEBUG_PAD_NAME (pad), pad);
2066 peerpad = GST_PAD_PEER (pad);
2067 if (G_UNLIKELY (peerpad == NULL))
2070 result = gst_pad_accept_caps (peerpad, caps);
2084 * @pad: a #GstPad to set the capabilities of.
2085 * @caps: a #GstCaps to set.
2087 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2088 * caps on the pad will be unreffed. This function refs the caps so you should
2089 * unref if as soon as you don't need it anymore.
2090 * It is possible to set NULL caps, which will make the pad unnegotiated
2093 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2094 * or bad parameters were provided to this function.
2099 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2101 GstPadSetCapsFunction setcaps;
2104 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2105 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2108 setcaps = GST_PAD_SETCAPSFUNC (pad);
2110 existing = GST_PAD_CAPS (pad);
2111 if (caps == existing)
2112 goto setting_same_caps;
2113 else if (caps && existing && gst_caps_is_equal (caps, existing))
2114 goto setting_same_caps;
2116 /* call setcaps function to configure the pad */
2117 if (setcaps != NULL && caps) {
2118 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2119 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2121 if (!setcaps (pad, caps))
2124 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2126 GST_CAT_DEBUG (GST_CAT_CAPS, "pad %s:%s was dispatching",
2127 GST_DEBUG_PAD_NAME (pad));
2131 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2132 GST_CAT_DEBUG (GST_CAT_CAPS, "%s:%s caps %" GST_PTR_FORMAT,
2133 GST_DEBUG_PAD_NAME (pad), caps);
2136 g_object_notify (G_OBJECT (pad), "caps");
2143 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2144 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2145 "caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
2152 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2153 GST_CAT_DEBUG (GST_CAT_CAPS,
2154 "pad %s:%s, caps %" GST_PTR_FORMAT " could not be set",
2155 GST_DEBUG_PAD_NAME (pad), caps);
2163 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2165 GstPadAcceptCapsFunction acceptcaps;
2166 GstPadSetCapsFunction setcaps;
2169 acceptcaps = GST_PAD_ACCEPTCAPSFUNC (pad);
2170 setcaps = GST_PAD_SETCAPSFUNC (pad);
2172 /* See if pad accepts the caps, by calling acceptcaps, only
2173 * needed if no setcaps function */
2174 if (setcaps == NULL && acceptcaps != NULL) {
2175 if (!acceptcaps (pad, caps))
2178 /* set caps on pad if call succeeds */
2179 res = gst_pad_set_caps (pad, caps);
2180 /* no need to unref the caps here, set_caps takes a ref and
2181 * our ref goes away when we leave this function. */
2187 GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
2192 /* returns TRUE if the src pad could be configured to accept the given caps */
2194 gst_pad_configure_src (GstPad * pad, GstCaps * caps)
2196 GstPadAcceptCapsFunction acceptcaps;
2197 GstPadSetCapsFunction setcaps;
2200 acceptcaps = GST_PAD_ACCEPTCAPSFUNC (pad);
2201 setcaps = GST_PAD_SETCAPSFUNC (pad);
2203 /* See if pad accepts the caps, by calling acceptcaps, only
2204 * needed if no setcaps function */
2205 if (setcaps == NULL && acceptcaps != NULL) {
2206 if (!acceptcaps (pad, caps))
2209 /* set caps on pad if call succeeds */
2210 res = gst_pad_set_caps (pad, caps);
2211 /* no need to unref the caps here, set_caps takes a ref and
2212 * our ref goes away when we leave this function. */
2218 GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
2224 * gst_pad_get_pad_template_caps:
2225 * @pad: a #GstPad to get the template capabilities from.
2227 * Gets the capabilities for @pad's template.
2229 * Returns: the #GstCaps of this pad template. If you intend to keep a reference
2230 * on the caps, make a copy (see gst_caps_copy ()).
2233 gst_pad_get_pad_template_caps (GstPad * pad)
2235 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2237 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2239 if (GST_PAD_PAD_TEMPLATE (pad))
2240 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2242 return gst_static_caps_get (&anycaps);
2248 * @pad: a #GstPad to get the peer of.
2250 * Gets the peer of @pad. This function refs the peer pad so
2251 * you need to unref it after use.
2253 * Returns: the peer #GstPad. Unref after usage.
2258 gst_pad_get_peer (GstPad * pad)
2262 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2265 result = GST_PAD_PEER (pad);
2267 gst_object_ref (result);
2274 * gst_pad_get_allowed_caps:
2275 * @srcpad: a #GstPad, it must a a source pad.
2277 * Gets the capabilities of the allowed media types that can flow through
2278 * @srcpad and its peer. The pad must be a source pad.
2279 * The caller must free the resulting caps.
2281 * Returns: the allowed #GstCaps of the pad link. Free the caps when
2282 * you no longer need it. This function returns NULL when the @srcpad has no
2288 gst_pad_get_allowed_caps (GstPad * srcpad)
2295 g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
2296 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
2300 peer = GST_PAD_PEER (srcpad);
2301 if (G_UNLIKELY (peer == NULL))
2304 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting allowed caps",
2305 GST_DEBUG_PAD_NAME (srcpad));
2307 gst_object_ref (peer);
2308 GST_UNLOCK (srcpad);
2309 mycaps = gst_pad_get_caps (srcpad);
2311 peercaps = gst_pad_get_caps (peer);
2312 gst_object_unref (peer);
2314 caps = gst_caps_intersect (mycaps, peercaps);
2315 gst_caps_unref (peercaps);
2316 gst_caps_unref (mycaps);
2318 GST_CAT_DEBUG (GST_CAT_CAPS, "allowed caps %" GST_PTR_FORMAT, caps);
2324 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
2325 GST_DEBUG_PAD_NAME (srcpad));
2326 GST_UNLOCK (srcpad);
2333 * gst_pad_get_negotiated_caps:
2336 * Gets the capabilities of the media type that currently flows through @pad
2339 * This function can be used on both src and sinkpads. Note that srcpads are
2340 * always negotiated before sinkpads so it is possible that the negotiated caps
2341 * on the srcpad do not match the negotiated caps of the peer.
2343 * Returns: the negotiated #GstCaps of the pad link. Free the caps when
2344 * you no longer need it. This function returns NULL when the @pad has no
2345 * peer or is not negotiated yet.
2350 gst_pad_get_negotiated_caps (GstPad * pad)
2355 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2359 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2362 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting negotiated caps",
2363 GST_DEBUG_PAD_NAME (pad));
2365 caps = GST_PAD_CAPS (pad);
2367 gst_caps_ref (caps);
2370 GST_CAT_DEBUG (GST_CAT_CAPS, "negotiated caps %" GST_PTR_FORMAT, caps);
2376 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
2377 GST_DEBUG_PAD_NAME (pad));
2385 * gst_pad_alloc_buffer:
2386 * @pad: a source #GstPad
2387 * @offset: the offset of the new buffer in the stream
2388 * @size: the size of the new buffer
2389 * @caps: the caps of the new buffer
2390 * @buf: a newly allocated buffer
2392 * Allocates a new, empty buffer optimized to push to pad @pad. This
2393 * function only works if @pad is a source pad and has a peer.
2395 * You need to check the caps of the buffer after performing this
2396 * function and renegotiate to the format if needed.
2398 * A new, empty #GstBuffer will be put in the @buf argument.
2400 * Returns: a result code indicating success of the operation. Any
2401 * result code other than GST_FLOW_OK is an error and @buf should
2403 * An error can occur if the pad is not connected or when the downstream
2404 * peer elements cannot provide an acceptable buffer.
2409 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
2414 GstPadBufferAllocFunction bufferallocfunc;
2415 gboolean caps_changed;
2417 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2418 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2419 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2422 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2423 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
2426 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2429 gst_object_ref (peer);
2432 if (G_LIKELY ((bufferallocfunc = peer->bufferallocfunc) == NULL))
2436 /* when the peer is flushing we cannot give a buffer */
2437 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (peer)))
2440 if (offset == GST_BUFFER_OFFSET_NONE) {
2441 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2442 "calling bufferallocfunc &%s (@%p) of peer pad %s:%s for size %d offset NONE",
2443 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2444 &bufferallocfunc, GST_DEBUG_PAD_NAME (peer), size);
2446 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2447 "calling bufferallocfunc &%s (@%p) of peer pad %s:%s for size %d offset %"
2448 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2449 &bufferallocfunc, GST_DEBUG_PAD_NAME (peer), size, offset);
2453 ret = bufferallocfunc (peer, offset, size, caps, buf);
2455 if (G_UNLIKELY (ret != GST_FLOW_OK))
2457 if (G_UNLIKELY (*buf == NULL))
2460 /* If the buffer alloc function didn't set up the caps like it should,
2462 if (caps && (GST_BUFFER_CAPS (*buf) == NULL)) {
2463 GST_WARNING ("Buffer allocation function for pad % " GST_PTR_FORMAT
2464 " did not set up caps. Setting", peer);
2466 gst_buffer_set_caps (*buf, caps);
2470 gst_object_unref (peer);
2472 /* FIXME, move capnego this into a base class? */
2473 caps = GST_BUFFER_CAPS (*buf);
2474 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2475 /* we got a new datatype on the pad, see if it can handle it */
2476 if (G_UNLIKELY (caps_changed)) {
2477 GST_DEBUG ("caps changed to %" GST_PTR_FORMAT, caps);
2478 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps)))
2479 goto not_negotiated;
2485 GST_CAT_DEBUG (GST_CAT_PADS, "%s:%s pad block stopped by flush",
2486 GST_DEBUG_PAD_NAME (pad));
2492 /* pad has no peer */
2493 GST_CAT_DEBUG (GST_CAT_PADS,
2494 "%s:%s called bufferallocfunc but had no peer",
2495 GST_DEBUG_PAD_NAME (pad));
2497 return GST_FLOW_NOT_LINKED;
2501 /* peer was flushing */
2503 gst_object_unref (peer);
2504 GST_CAT_DEBUG (GST_CAT_PADS,
2505 "%s:%s called bufferallocfunc but peer was flushing",
2506 GST_DEBUG_PAD_NAME (pad));
2507 return GST_FLOW_WRONG_STATE;
2509 /* fallback case, allocate a buffer of our own, add pad caps. */
2512 GST_CAT_DEBUG (GST_CAT_PADS,
2513 "%s:%s fallback buffer alloc", GST_DEBUG_PAD_NAME (pad));
2514 *buf = gst_buffer_new_and_alloc (size);
2515 GST_BUFFER_OFFSET (*buf) = offset;
2516 gst_buffer_set_caps (*buf, caps);
2524 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2525 "alloc function returned unacceptable buffer");
2526 return GST_FLOW_NOT_NEGOTIATED;
2530 gst_object_unref (peer);
2531 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2532 "alloc function returned error %s", gst_flow_get_name (ret));
2538 * gst_pad_get_internal_links_default:
2539 * @pad: the #GstPad to get the internal links of.
2541 * Gets a list of pads to which the given pad is linked to
2542 * inside of the parent element.
2543 * This is the default handler, and thus returns a list of all of the
2544 * pads inside the parent element with opposite direction.
2545 * The caller must free this list after use.
2547 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
2552 gst_pad_get_internal_links_default (GstPad * pad)
2557 GstPadDirection direction;
2559 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2561 direction = pad->direction;
2563 parent = GST_PAD_PARENT (pad);
2567 parent_pads = parent->pads;
2569 while (parent_pads) {
2570 GstPad *parent_pad = GST_PAD_CAST (parent_pads->data);
2572 if (parent_pad->direction != direction) {
2573 res = g_list_prepend (res, parent_pad);
2576 parent_pads = g_list_next (parent_pads);
2583 * gst_pad_get_internal_links:
2584 * @pad: the #GstPad to get the internal links of.
2586 * Gets a list of pads to which the given pad is linked to
2587 * inside of the parent element.
2588 * The caller must free this list after use.
2590 * Returns: a newly allocated #GList of pads.
2595 gst_pad_get_internal_links (GstPad * pad)
2599 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2601 if (GST_PAD_INTLINKFUNC (pad))
2602 res = GST_PAD_INTLINKFUNC (pad) (pad);
2609 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
2614 GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
2617 result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
2619 orig = pads = gst_pad_get_internal_links (pad);
2622 GstPad *eventpad = GST_PAD_CAST (pads->data);
2624 pads = g_list_next (pads);
2626 if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
2627 /* for each pad we send to, we should ref the event; it's up
2628 * to downstream to unref again when handled. */
2629 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
2630 event, gst_event_type_get_name (GST_EVENT_TYPE (event)),
2631 GST_DEBUG_PAD_NAME (eventpad));
2632 gst_event_ref (event);
2633 gst_pad_push_event (eventpad, event);
2635 /* we only send the event on one pad, multi-sinkpad elements
2636 * should implement a handler */
2637 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
2638 event, gst_event_type_get_name (GST_EVENT_TYPE (event)),
2639 GST_DEBUG_PAD_NAME (eventpad));
2640 result = gst_pad_push_event (eventpad, event);
2644 /* we handled the incoming event so we unref once */
2645 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
2646 gst_event_unref (event);
2655 * gst_pad_event_default:
2656 * @pad: a #GstPad to call the default event handler on.
2657 * @event: the #GstEvent to handle.
2659 * Invokes the default event handler for the given pad. End-of-stream and
2660 * discontinuity events are handled specially, and then the event is sent to all
2661 * pads internally linked to @pad. Note that if there are many possible sink
2662 * pads that are internally linked to @pad, only one will be sent an event.
2663 * Multi-sinkpad elements should implement custom event handlers.
2665 * Returns: TRUE if the event was sent succesfully.
2668 gst_pad_event_default (GstPad * pad, GstEvent * event)
2670 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2671 g_return_val_if_fail (event != NULL, FALSE);
2673 switch (GST_EVENT_TYPE (event)) {
2676 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
2677 gst_pad_pause_task (pad);
2683 return gst_pad_event_default_dispatch (pad, event);
2687 * gst_pad_dispatcher:
2688 * @pad: a #GstPad to dispatch.
2689 * @dispatch: the #GstDispatcherFunction to call.
2690 * @data: gpointer user data passed to the dispatcher function.
2692 * Invokes the given dispatcher function on all pads that are
2693 * internally linked to the given pad.
2694 * The GstPadDispatcherFunction should return TRUE when no further pads
2695 * need to be processed.
2697 * Returns: TRUE if one of the dispatcher functions returned TRUE.
2700 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
2703 gboolean res = FALSE;
2704 GList *int_pads, *orig;
2706 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2707 g_return_val_if_fail (dispatch != NULL, FALSE);
2709 orig = int_pads = gst_pad_get_internal_links (pad);
2712 GstPad *int_pad = GST_PAD_CAST (int_pads->data);
2713 GstPad *int_peer = GST_PAD_PEER (int_pad);
2716 res = dispatch (int_peer, data);
2720 int_pads = g_list_next (int_pads);
2730 * @pad: a #GstPad to invoke the default query on.
2731 * @query: the #GstQuery to perform.
2733 * Dispatches a query to a pad. The query should have been allocated by the
2734 * caller via one of the type-specific allocation functions in gstquery.h. The
2735 * element is responsible for filling the query with an appropriate response,
2736 * which should then be parsed with a type-specific query parsing function.
2738 * Again, the caller is responsible for both the allocation and deallocation of
2739 * the query structure.
2741 * Returns: TRUE if the query could be performed.
2744 gst_pad_query (GstPad * pad, GstQuery * query)
2746 GstPadQueryFunction func;
2748 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2749 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2751 GST_DEBUG ("sending query %p to pad %s:%s", query, GST_DEBUG_PAD_NAME (pad));
2753 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
2756 return func (pad, query);
2760 GST_DEBUG ("pad had no query function");
2766 * gst_pad_query_default:
2767 * @pad: a #GstPad to call the default query handler on.
2768 * @query: the #GstQuery to handle.
2770 * Invokes the default query handler for the given pad.
2771 * The query is sent to all pads internally linked to @pad. Note that
2772 * if there are many possible sink pads that are internally linked to
2773 * @pad, only one will be sent the query.
2774 * Multi-sinkpad elements should implement custom query handlers.
2776 * Returns: TRUE if the query was performed succesfully.
2779 gst_pad_query_default (GstPad * pad, GstQuery * query)
2781 switch (GST_QUERY_TYPE (query)) {
2782 case GST_QUERY_POSITION:
2783 case GST_QUERY_SEEKING:
2784 case GST_QUERY_FORMATS:
2785 case GST_QUERY_LATENCY:
2786 case GST_QUERY_JITTER:
2787 case GST_QUERY_RATE:
2788 case GST_QUERY_CONVERT:
2790 return gst_pad_dispatcher
2791 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
2795 #ifndef GST_DISABLE_LOADSAVE
2796 /* FIXME: why isn't this on a GstElement ? */
2798 * gst_pad_load_and_link:
2799 * @self: an #xmlNodePtr to read the description from.
2800 * @parent: the #GstObject element that owns the pad.
2802 * Reads the pad definition from the XML node and links the given pad
2803 * in the element to a pad of an element up in the hierarchy.
2806 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
2808 xmlNodePtr field = self->xmlChildrenNode;
2809 GstPad *pad = NULL, *targetpad;
2813 GstObject *grandparent;
2817 if (!strcmp ((char *) field->name, "name")) {
2818 name = (gchar *) xmlNodeGetContent (field);
2819 pad = gst_element_get_pad (GST_ELEMENT (parent), name);
2821 } else if (!strcmp ((char *) field->name, "peer")) {
2822 peer = (gchar *) xmlNodeGetContent (field);
2824 field = field->next;
2826 g_return_if_fail (pad != NULL);
2831 split = g_strsplit (peer, ".", 2);
2833 if (split[0] == NULL || split[1] == NULL) {
2834 GST_CAT_DEBUG (GST_CAT_XML,
2835 "Could not parse peer '%s' for pad %s:%s, leaving unlinked",
2836 peer, GST_DEBUG_PAD_NAME (pad));
2843 g_return_if_fail (split[0] != NULL);
2844 g_return_if_fail (split[1] != NULL);
2846 grandparent = gst_object_get_parent (parent);
2848 if (grandparent && GST_IS_BIN (grandparent)) {
2849 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
2856 targetpad = gst_element_get_pad (target, split[1]);
2858 if (targetpad == NULL)
2861 gst_pad_link (pad, targetpad);
2868 * gst_pad_save_thyself:
2869 * @pad: a #GstPad to save.
2870 * @parent: the parent #xmlNodePtr to save the description in.
2872 * Saves the pad into an xml representation.
2874 * Returns: the #xmlNodePtr representation of the pad.
2877 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
2882 g_return_val_if_fail (GST_IS_PAD (object), NULL);
2884 pad = GST_PAD (object);
2886 xmlNewChild (parent, NULL, (xmlChar *) "name",
2887 (xmlChar *) GST_PAD_NAME (pad));
2888 if (GST_PAD_PEER (pad) != NULL) {
2891 peer = GST_PAD_PEER (pad);
2892 /* first check to see if the peer's parent's parent is the same */
2893 /* we just save it off */
2894 content = g_strdup_printf ("%s.%s",
2895 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
2896 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
2899 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
2906 * gst_ghost_pad_save_thyself:
2907 * @pad: a ghost #GstPad to save.
2908 * @parent: the parent #xmlNodePtr to save the description in.
2910 * Saves the ghost pad into an xml representation.
2912 * Returns: the #xmlNodePtr representation of the pad.
2915 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
2919 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
2921 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
2922 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
2923 xmlNewChild (self, NULL, (xmlChar *) "parent",
2924 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
2926 /* FIXME FIXME FIXME! */
2931 #endif /* GST_DISABLE_LOADSAVE */
2934 * should be called with pad lock held
2938 static GstFlowReturn
2939 handle_pad_block (GstPad * pad)
2941 GstPadBlockCallback callback;
2943 GstFlowReturn ret = GST_FLOW_OK;
2945 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2946 "signal block taken on pad %s:%s", GST_DEBUG_PAD_NAME (pad));
2948 /* need to grab extra ref for the callbacks */
2949 gst_object_ref (pad);
2951 callback = pad->block_callback;
2953 user_data = pad->block_data;
2955 callback (pad, TRUE, user_data);
2958 GST_PAD_BLOCK_SIGNAL (pad);
2961 while (GST_PAD_IS_BLOCKED (pad)) {
2962 if (GST_PAD_IS_FLUSHING (pad))
2964 GST_PAD_BLOCK_WAIT (pad);
2965 if (GST_PAD_IS_FLUSHING (pad))
2969 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
2971 callback = pad->block_callback;
2973 user_data = pad->block_data;
2975 callback (pad, FALSE, user_data);
2978 GST_PAD_BLOCK_SIGNAL (pad);
2981 gst_object_unref (pad);
2987 gst_object_unref (pad);
2988 return GST_FLOW_WRONG_STATE;
2992 /**********************************************************************
2993 * Data passing functions
2997 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
3000 GValue args[2] = { {0}, {0} };
3005 g_value_init (&ret, G_TYPE_BOOLEAN);
3006 g_value_set_boolean (&ret, TRUE);
3007 g_value_init (&args[0], GST_TYPE_PAD);
3008 g_value_set_object (&args[0], pad);
3009 g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
3010 gst_value_set_mini_object (&args[1], obj);
3012 if (GST_IS_EVENT (obj))
3013 detail = event_quark;
3015 detail = buffer_quark;
3018 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
3019 res = g_value_get_boolean (&ret);
3022 g_value_unset (&ret);
3023 g_value_unset (&args[0]);
3024 g_value_unset (&args[1]);
3031 * @pad: a sink #GstPad.
3032 * @buffer: the #GstBuffer to send.
3034 * Chain a buffer to @pad.
3036 * Returns: a #GstFlowReturn from the pad.
3041 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
3044 gboolean caps_changed;
3045 GstPadChainFunction chainfunc;
3047 gboolean emit_signal;
3049 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3050 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3052 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3053 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3055 GST_STREAM_LOCK (pad);
3058 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3061 caps = GST_BUFFER_CAPS (buffer);
3062 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3064 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3067 /* see if the signal should be emited, we emit before caps nego as
3068 * we might drop the buffer and do capsnego for nothing. */
3069 if (G_UNLIKELY (emit_signal)) {
3070 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3074 /* we got a new datatype on the pad, see if it can handle it */
3075 if (G_UNLIKELY (caps_changed)) {
3076 GST_DEBUG ("caps changed to %" GST_PTR_FORMAT, caps);
3077 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
3078 goto not_negotiated;
3081 /* NOTE: we read the chainfunc unlocked.
3082 * we cannot hold the lock for the pad so we might send
3083 * the data to the wrong function. This is not really a
3084 * problem since functions are assigned at creation time
3085 * and don't change that often... */
3086 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
3089 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3090 "calling chainfunction &%s of pad %s:%s",
3091 GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_DEBUG_PAD_NAME (pad));
3093 ret = chainfunc (pad, buffer);
3095 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3096 "called chainfunction &%s of pad %s:%s, returned %s",
3097 GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_DEBUG_PAD_NAME (pad),
3098 gst_flow_get_name (ret));
3100 GST_STREAM_UNLOCK (pad);
3107 gst_buffer_unref (buffer);
3108 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3109 "pushing, but pad was flushing");
3111 GST_STREAM_UNLOCK (pad);
3112 return GST_FLOW_WRONG_STATE;
3116 gst_buffer_unref (buffer);
3117 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3118 GST_STREAM_UNLOCK (pad);
3123 gst_buffer_unref (buffer);
3124 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3125 "pushing buffer but pad did not accept");
3126 GST_STREAM_UNLOCK (pad);
3127 return GST_FLOW_NOT_NEGOTIATED;
3131 gst_buffer_unref (buffer);
3132 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3133 "pushing, but not chainhandler");
3134 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3135 ("push on pad %s:%s but it has no chainfunction",
3136 GST_DEBUG_PAD_NAME (pad)));
3137 GST_STREAM_UNLOCK (pad);
3138 return GST_FLOW_ERROR;
3144 * @pad: a source #GstPad.
3145 * @buffer: the #GstBuffer to push.
3147 * Pushes a buffer to the peer of @pad.
3148 * buffer probes will be triggered before the buffer gets pushed.
3150 * Returns: a #GstFlowReturn from the peer pad.
3155 gst_pad_push (GstPad * pad, GstBuffer * buffer)
3160 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3161 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3162 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3163 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3167 /* FIXME: this check can go away; pad_set_blocked could be implemented with
3168 * probes completely */
3169 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3170 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
3173 /* we emit signals on the pad arg, the peer will have a chance to
3174 * emit in the _chain() function */
3175 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
3176 /* unlock before emitting */
3179 /* if the signal handler returned FALSE, it means we should just drop the
3181 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3187 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3189 gst_object_ref (peer);
3192 ret = gst_pad_chain (peer, buffer);
3194 gst_object_unref (peer);
3198 /* ERROR recovery here */
3201 gst_buffer_unref (buffer);
3202 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
3208 gst_buffer_unref (buffer);
3209 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3214 gst_buffer_unref (buffer);
3215 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3216 "pushing, but it was not linked");
3218 return GST_FLOW_NOT_LINKED;
3223 * gst_pad_check_pull_range:
3224 * @pad: a sink #GstPad.
3226 * Checks if a #gst_pad_pull_range() can be performed on the peer
3227 * source pad. This function is used by plugins that want to check
3228 * if they can use random access on the peer source pad.
3230 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
3231 * if it needs to perform some logic to determine if pull_range is
3234 * Returns: a gboolean with the result.
3239 gst_pad_check_pull_range (GstPad * pad)
3243 GstPadCheckGetRangeFunction checkgetrangefunc;
3245 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3248 if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
3249 goto wrong_direction;
3251 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3254 gst_object_ref (peer);
3257 /* see note in above function */
3258 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
3259 /* FIXME, kindoff ghetto */
3260 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
3262 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3263 "calling checkgetrangefunc %s of peer pad %s:%s",
3264 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
3266 ret = checkgetrangefunc (peer);
3269 gst_object_unref (peer);
3273 /* ERROR recovery here */
3281 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3282 "checking pull range, but it was not linked");
3289 * gst_pad_get_range:
3290 * @pad: a src #GstPad.
3291 * @offset: The start offset of the buffer
3292 * @size: The length of the buffer
3293 * @buffer: a pointer to hold the #GstBuffer.
3295 * Calls the getrange function of @pad.
3297 * Returns: a #GstFlowReturn from the pad.
3302 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
3303 GstBuffer ** buffer)
3306 GstPadGetRangeFunction getrangefunc;
3307 gboolean emit_signal;
3309 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3310 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3311 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3313 GST_STREAM_LOCK (pad);
3316 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3319 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3322 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
3325 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3326 "calling getrangefunc %s of peer pad %s:%s, offset %"
3327 G_GUINT64_FORMAT ", size %u",
3328 GST_DEBUG_FUNCPTR_NAME (getrangefunc), GST_DEBUG_PAD_NAME (pad),
3331 ret = getrangefunc (pad, offset, size, buffer);
3333 /* can only fire the signal if we have a valid buffer */
3334 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3335 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3339 GST_STREAM_UNLOCK (pad);
3346 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3347 "pulling range, but pad was flushing");
3349 GST_STREAM_UNLOCK (pad);
3350 return GST_FLOW_WRONG_STATE;
3354 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3355 ("pullrange on pad %s:%s but it has no getrangefunction",
3356 GST_DEBUG_PAD_NAME (pad)));
3357 GST_STREAM_UNLOCK (pad);
3358 return GST_FLOW_ERROR;
3362 GST_DEBUG ("Dropping data after FALSE probe return");
3363 GST_STREAM_UNLOCK (pad);
3364 gst_buffer_unref (*buffer);
3366 return GST_FLOW_UNEXPECTED;
3372 * gst_pad_pull_range:
3373 * @pad: a sink #GstPad.
3374 * @offset: The start offset of the buffer
3375 * @size: The length of the buffer
3376 * @buffer: a pointer to hold the #GstBuffer.
3378 * Pulls a buffer from the peer pad. @pad must be a linked
3381 * Returns: a #GstFlowReturn from the peer pad.
3386 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
3387 GstBuffer ** buffer)
3391 gboolean emit_signal;
3393 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3394 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3396 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3400 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3401 handle_pad_block (pad);
3403 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3406 /* signal emision for the pad, peer has chance to emit when
3407 * we call _get_range() */
3408 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3410 gst_object_ref (peer);
3413 ret = gst_pad_get_range (peer, offset, size, buffer);
3415 gst_object_unref (peer);
3417 /* can only fire the signal if we have a valid buffer */
3418 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3419 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3424 /* ERROR recovery here */
3427 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3428 "pulling range, but it was not linked");
3430 return GST_FLOW_NOT_LINKED;
3434 GST_DEBUG ("Dropping data after FALSE probe return");
3435 gst_buffer_unref (*buffer);
3437 return GST_FLOW_UNEXPECTED;
3442 * gst_pad_push_event:
3443 * @pad: a #GstPad to push the event to.
3444 * @event: the #GstEvent to send to the pad.
3446 * Sends the event to the peer of the given pad. This function is
3447 * mainly used by elements to send events to their peer
3450 * Returns: TRUE if the event was handled.
3455 gst_pad_push_event (GstPad * pad, GstEvent * event)
3460 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3461 g_return_val_if_fail (event != NULL, FALSE);
3462 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
3465 switch (GST_EVENT_TYPE (event)) {
3466 case GST_EVENT_FLUSH_START:
3467 GST_PAD_SET_FLUSHING (pad);
3469 case GST_EVENT_FLUSH_STOP:
3470 GST_PAD_UNSET_FLUSHING (pad);
3476 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3477 if (GST_EVENT_TYPE (event) == GST_EVENT_FLUSH_START) {
3478 GST_PAD_BLOCK_SIGNAL (pad);
3482 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3485 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3490 peerpad = GST_PAD_PEER (pad);
3491 if (peerpad == NULL)
3494 GST_LOG_OBJECT (peerpad, "sending event on peerpad");
3495 gst_object_ref (peerpad);
3498 result = gst_pad_send_event (peerpad, event);
3500 gst_object_unref (peerpad);
3501 GST_LOG_OBJECT (peerpad, "sent event on peerpad");
3505 /* ERROR handling */
3508 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
3509 gst_event_unref (event);
3514 gst_event_unref (event);
3521 * gst_pad_send_event:
3522 * @pad: a #GstPad to send the event to.
3523 * @event: the #GstEvent to send to the pad.
3525 * Sends the event to the pad. This function can be used
3526 * by applications to send events in the pipeline.
3528 * Returns: TRUE if the event was handled.
3531 gst_pad_send_event (GstPad * pad, GstEvent * event)
3533 gboolean result = FALSE;
3534 GstPadEventFunction eventfunc;
3535 gboolean emit_signal;
3537 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3538 g_return_val_if_fail (event != NULL, FALSE);
3541 if (GST_PAD_IS_SINK (pad) && !GST_EVENT_IS_DOWNSTREAM (event))
3542 goto wrong_direction;
3543 if (GST_PAD_IS_SRC (pad) && !GST_EVENT_IS_UPSTREAM (event))
3544 goto wrong_direction;
3546 if (GST_EVENT_SRC (event) == NULL) {
3547 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
3548 GST_EVENT_SRC (event) = gst_object_ref (pad);
3551 switch (GST_EVENT_TYPE (event)) {
3552 case GST_EVENT_FLUSH_START:
3553 GST_CAT_DEBUG (GST_CAT_EVENT,
3554 "have event type %d (FLUSH_START) on pad %s:%s",
3555 GST_EVENT_TYPE (event), GST_DEBUG_PAD_NAME (pad));
3557 /* can't even accept a flush begin event when flushing */
3558 if (GST_PAD_IS_FLUSHING (pad))
3560 GST_PAD_SET_FLUSHING (pad);
3561 GST_CAT_DEBUG (GST_CAT_EVENT, "set flush flag");
3563 case GST_EVENT_FLUSH_STOP:
3564 GST_PAD_UNSET_FLUSHING (pad);
3565 GST_CAT_DEBUG (GST_CAT_EVENT, "cleared flush flag");
3568 GST_CAT_DEBUG (GST_CAT_EVENT, "have event type %s on pad %s:%s",
3569 gst_event_type_get_name (GST_EVENT_TYPE (event)),
3570 GST_DEBUG_PAD_NAME (pad));
3572 if (GST_PAD_IS_FLUSHING (pad))
3577 if ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL)
3580 emit_signal = GST_PAD_DO_EVENT_SIGNALS (pad) > 0;
3583 if (G_UNLIKELY (emit_signal)) {
3584 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3588 result = eventfunc (GST_PAD_CAST (pad), event);
3592 /* ERROR handling */
3595 g_warning ("pad %s:%s sending event in wrong direction",
3596 GST_DEBUG_PAD_NAME (pad));
3598 gst_event_unref (event);
3603 g_warning ("pad %s:%s has no event handler, file a bug.",
3604 GST_DEBUG_PAD_NAME (pad));
3606 gst_event_unref (event);
3612 GST_CAT_INFO (GST_CAT_EVENT, "Received event on flushing pad. Discarding");
3613 gst_event_unref (event);
3618 GST_DEBUG ("Dropping event after FALSE probe return");
3619 gst_event_unref (event);
3625 * gst_pad_set_element_private:
3626 * @pad: the #GstPad to set the private data of.
3627 * @priv: The private data to attach to the pad.
3629 * Set the given private data gpointer on the pad.
3630 * This function can only be used by the element that owns the pad.
3633 gst_pad_set_element_private (GstPad * pad, gpointer priv)
3635 pad->element_private = priv;
3639 * gst_pad_get_element_private:
3640 * @pad: the #GstPad to get the private data of.
3642 * Gets the private data of a pad.
3644 * Returns: a #gpointer to the private data.
3647 gst_pad_get_element_private (GstPad * pad)
3649 return pad->element_private;
3653 * gst_pad_start_task:
3654 * @pad: the #GstPad to start the task of
3655 * @func: the task function to call
3656 * @data: data passed to the task function
3658 * Starts a task that repeadedly calls @func with @data. This function
3659 * is nostly used in the pad activation function to start the
3660 * dataflow. This function will automatically acauire the STREAM_LOCK of
3661 * the pad before calling @func.
3663 * Returns: a TRUE if the task could be started.
3666 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
3670 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3671 g_return_val_if_fail (func != NULL, FALSE);
3674 task = GST_PAD_TASK (pad);
3676 task = gst_task_create (func, data);
3677 gst_task_set_lock (task, GST_STREAM_GET_LOCK (pad));
3678 GST_PAD_TASK (pad) = task;
3680 gst_task_start (task);
3687 * gst_pad_pause_task:
3688 * @pad: the #GstPad to pause the task of
3690 * Pause the task of @pad. This function will also make sure that the
3691 * function executed by the task will effectively stop.
3693 * Returns: a TRUE if the task could be paused or FALSE when the pad
3697 gst_pad_pause_task (GstPad * pad)
3701 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3704 task = GST_PAD_TASK (pad);
3707 gst_task_pause (task);
3710 GST_STREAM_LOCK (pad);
3711 GST_STREAM_UNLOCK (pad);
3717 GST_DEBUG_OBJECT (pad, "pad has no task");
3724 * gst_pad_stop_task:
3725 * @pad: the #GstPad to stop the task of
3727 * Stop the task of @pad. This function will also make sure that the
3728 * function executed by the task will effectively stop if not called
3729 * from the GstTaskFunction.
3731 * This function will deadlock if called from the GstTaskFunction of
3732 * the task. Use #gst_task_pause() instead.
3734 * Regardless of whether the pad has a task, the stream lock is acquired and
3735 * released so as to ensure that streaming through this pad has finished.
3737 * Returns: a TRUE if the task could be stopped or FALSE on error.
3740 gst_pad_stop_task (GstPad * pad)
3744 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3747 task = GST_PAD_TASK (pad);
3750 GST_PAD_TASK (pad) = NULL;
3751 gst_task_stop (task);
3754 GST_STREAM_LOCK (pad);
3755 GST_STREAM_UNLOCK (pad);
3757 gst_task_join (task);
3759 gst_object_unref (task);
3767 GST_STREAM_LOCK (pad);
3768 GST_STREAM_UNLOCK (pad);