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_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_range() to push out
55 * or pull in a buffer.
57 * To send a #GstEvent on a pad, use gst_pad_send_event() and
58 * gst_pad_push_event().
60 * Last reviewed on 2006-07-06 (0.10.9)
63 #include "gst_private.h"
66 #include "gstpadtemplate.h"
67 #include "gstenumtypes.h"
68 #include "gstmarshal.h"
73 #include "glib-compat-private.h"
75 GST_DEBUG_CATEGORY_STATIC (debug_dataflow);
76 #define GST_CAT_DEFAULT GST_CAT_PADS
78 /* Pad signals and args */
98 static void gst_pad_class_init (GstPadClass * klass);
99 static void gst_pad_init (GstPad * pad);
100 static void gst_pad_dispose (GObject * object);
101 static void gst_pad_finalize (GObject * object);
102 static void gst_pad_set_property (GObject * object, guint prop_id,
103 const GValue * value, GParamSpec * pspec);
104 static void gst_pad_get_property (GObject * object, guint prop_id,
105 GValue * value, GParamSpec * pspec);
107 static GstFlowReturn handle_pad_block (GstPad * pad);
108 static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
109 static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
110 static gboolean gst_pad_activate_default (GstPad * pad);
111 static gboolean gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps);
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_CUSTOM_SUCCESS, "custom-success", 0},
133 {GST_FLOW_RESEND, "resend", 0},
134 {GST_FLOW_OK, "ok", 0},
135 {GST_FLOW_NOT_LINKED, "not-linked", 0},
136 {GST_FLOW_WRONG_STATE, "wrong-state", 0},
137 {GST_FLOW_UNEXPECTED, "unexpected", 0},
138 {GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
139 {GST_FLOW_ERROR, "error", 0},
140 {GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
141 {GST_FLOW_CUSTOM_ERROR, "custom-error", 0},
148 * @ret: a #GstFlowReturn to get the name of.
150 * Gets a string representing the given flow return.
152 * Returns: a static string with the name of the flow return.
154 G_CONST_RETURN gchar *
155 gst_flow_get_name (GstFlowReturn ret)
159 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
161 for (i = 0; flow_quarks[i].name; i++) {
162 if (ret == flow_quarks[i].ret)
163 return flow_quarks[i].name;
170 * @ret: a #GstFlowReturn to get the quark of.
172 * Get the unique quark for the given GstFlowReturn.
174 * Returns: the quark associated with the flow return or 0 if an
175 * invalid return was specified.
178 gst_flow_to_quark (GstFlowReturn ret)
182 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
184 for (i = 0; flow_quarks[i].name; i++) {
185 if (ret == flow_quarks[i].ret)
186 return flow_quarks[i].quark;
192 gst_pad_get_type (void)
194 static GType gst_pad_type = 0;
196 if (G_UNLIKELY (gst_pad_type == 0)) {
197 static const GTypeInfo pad_info = {
198 sizeof (GstPadClass), NULL, NULL,
199 (GClassInitFunc) gst_pad_class_init, NULL, NULL,
202 (GInstanceInitFunc) gst_pad_init, NULL
206 gst_pad_type = g_type_register_static (GST_TYPE_OBJECT, "GstPad",
209 buffer_quark = g_quark_from_static_string ("buffer");
210 event_quark = g_quark_from_static_string ("event");
212 for (i = 0; flow_quarks[i].name; i++) {
213 flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name);
216 GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW",
217 GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads");
223 _gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
224 GValue * return_accu, const GValue * handler_return, gpointer dummy)
226 gboolean ret = g_value_get_boolean (handler_return);
228 GST_DEBUG ("accumulated %d", ret);
229 g_value_set_boolean (return_accu, ret);
235 default_have_data (GstPad * pad, GstMiniObject * o)
241 gst_pad_class_init (GstPadClass * klass)
243 GObjectClass *gobject_class;
244 GstObjectClass *gstobject_class;
246 gobject_class = G_OBJECT_CLASS (klass);
247 gstobject_class = GST_OBJECT_CLASS (klass);
249 parent_class = g_type_class_peek_parent (klass);
251 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pad_dispose);
252 gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_pad_finalize);
253 gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pad_set_property);
254 gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pad_get_property);
258 * @pad: the pad that emitted the signal
259 * @peer: the peer pad that has been connected
261 * Signals that a pad has been linked to the peer pad.
263 gst_pad_signals[PAD_LINKED] =
264 g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
265 G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
266 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
269 * @pad: the pad that emitted the signal
270 * @peer: the peer pad that has been disconnected
272 * Signals that a pad has been unlinked from the peer pad.
274 gst_pad_signals[PAD_UNLINKED] =
275 g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
276 G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
277 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
279 * GstPad::request-link:
280 * @pad: the pad that emitted the signal
281 * @peer: the peer pad for which a connection is requested
283 * Signals that a pad connection has been requested.
285 gst_pad_signals[PAD_REQUEST_LINK] =
286 g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
287 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
288 NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
292 * @pad: the pad that emitted the signal
293 * @mini_obj: new data
295 * Signals that new data is available on the pad. This signal is used
296 * internally for implementing pad probes.
297 * See gst_pad_add_*_probe functions.
299 * Returns: %TRUE to keep the data, %FALSE to drop it
301 gst_pad_signals[PAD_HAVE_DATA] =
302 g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
303 G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
304 G_STRUCT_OFFSET (GstPadClass, have_data),
305 _gst_do_pass_data_accumulator,
306 NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
307 GST_TYPE_MINI_OBJECT);
309 g_object_class_install_property (gobject_class, PAD_PROP_CAPS,
310 g_param_spec_boxed ("caps", "Caps", "The capabilities of the pad",
311 GST_TYPE_CAPS, G_PARAM_READABLE));
312 g_object_class_install_property (gobject_class, PAD_PROP_DIRECTION,
313 g_param_spec_enum ("direction", "Direction", "The direction of the pad",
314 GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
315 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
316 /* FIXME, Make G_PARAM_CONSTRUCT_ONLY when we fix ghostpads. */
317 g_object_class_install_property (gobject_class, PAD_PROP_TEMPLATE,
318 g_param_spec_object ("template", "Template",
319 "The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
322 #ifndef GST_DISABLE_LOADSAVE
323 gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_pad_save_thyself);
325 gstobject_class->path_string_separator = ".";
327 klass->have_data = default_have_data;
331 gst_pad_init (GstPad * pad)
333 GST_PAD_DIRECTION (pad) = GST_PAD_UNKNOWN;
334 GST_PAD_PEER (pad) = NULL;
336 GST_PAD_CHAINFUNC (pad) = NULL;
338 GST_PAD_LINKFUNC (pad) = NULL;
340 GST_PAD_CAPS (pad) = NULL;
341 GST_PAD_GETCAPSFUNC (pad) = NULL;
343 GST_PAD_ACTIVATEFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_activate_default);
344 GST_PAD_EVENTFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_event_default);
345 GST_PAD_QUERYTYPEFUNC (pad) =
346 GST_DEBUG_FUNCPTR (gst_pad_get_query_types_default);
347 GST_PAD_QUERYFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_query_default);
348 GST_PAD_INTLINKFUNC (pad) =
349 GST_DEBUG_FUNCPTR (gst_pad_get_internal_links_default);
350 GST_PAD_ACCEPTCAPSFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_acceptcaps_default);
352 pad->do_buffer_signals = 0;
353 pad->do_event_signals = 0;
355 /* FIXME, should be set flushing initially, see #339326 */
356 GST_PAD_UNSET_FLUSHING (pad);
358 pad->preroll_lock = g_mutex_new ();
359 pad->preroll_cond = g_cond_new ();
361 pad->stream_rec_lock = g_new (GStaticRecMutex, 1);
362 g_static_rec_mutex_init (pad->stream_rec_lock);
364 pad->block_cond = g_cond_new ();
368 gst_pad_dispose (GObject * object)
370 GstPad *pad = GST_PAD (object);
372 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pad, "dispose");
374 /* we don't hold a ref to the peer so we can just set the
376 GST_PAD_PEER (pad) = NULL;
379 gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
381 gst_pad_set_pad_template (pad, NULL);
383 G_OBJECT_CLASS (parent_class)->dispose (object);
387 gst_pad_finalize (GObject * object)
389 GstPad *pad = GST_PAD (object);
392 /* in case the task is still around, clean it up */
393 if ((task = GST_PAD_TASK (pad))) {
394 gst_task_join (task);
395 GST_PAD_TASK (pad) = NULL;
396 gst_object_unref (task);
399 if (pad->stream_rec_lock) {
400 g_static_rec_mutex_free (pad->stream_rec_lock);
401 g_free (pad->stream_rec_lock);
402 pad->stream_rec_lock = NULL;
404 if (pad->preroll_lock) {
405 g_mutex_free (pad->preroll_lock);
406 g_cond_free (pad->preroll_cond);
407 pad->preroll_lock = NULL;
408 pad->preroll_cond = NULL;
410 if (pad->block_cond) {
411 g_cond_free (pad->block_cond);
412 pad->block_cond = NULL;
415 G_OBJECT_CLASS (parent_class)->finalize (object);
419 gst_pad_set_property (GObject * object, guint prop_id,
420 const GValue * value, GParamSpec * pspec)
422 g_return_if_fail (GST_IS_PAD (object));
425 case PAD_PROP_DIRECTION:
426 GST_PAD_DIRECTION (object) = g_value_get_enum (value);
428 case PAD_PROP_TEMPLATE:
429 gst_pad_set_pad_template (GST_PAD_CAST (object),
430 (GstPadTemplate *) g_value_get_object (value));
433 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
439 gst_pad_get_property (GObject * object, guint prop_id,
440 GValue * value, GParamSpec * pspec)
442 g_return_if_fail (GST_IS_PAD (object));
446 GST_OBJECT_LOCK (object);
447 g_value_set_boxed (value, GST_PAD_CAPS (object));
448 GST_OBJECT_UNLOCK (object);
450 case PAD_PROP_DIRECTION:
451 g_value_set_enum (value, GST_PAD_DIRECTION (object));
453 case PAD_PROP_TEMPLATE:
454 g_value_set_object (value, GST_PAD_PAD_TEMPLATE (object));
457 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
464 * @name: the name of the new pad.
465 * @direction: the #GstPadDirection of the pad.
467 * Creates a new pad with the given name in the given direction.
468 * If name is NULL, a guaranteed unique name (across all pads)
470 * This function makes a copy of the name so you can safely free the name.
472 * Returns: a new #GstPad, or NULL in case of an error.
477 gst_pad_new (const gchar * name, GstPadDirection direction)
479 return g_object_new (GST_TYPE_PAD,
480 "name", name, "direction", direction, NULL);
484 * gst_pad_new_from_template:
485 * @templ: the pad template to use
486 * @name: the name of the element
488 * Creates a new pad with the given name from the given template.
489 * If name is NULL, a guaranteed unique name (across all pads)
491 * This function makes a copy of the name so you can safely free the name.
493 * Returns: a new #GstPad, or NULL in case of an error.
496 gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
498 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
500 return g_object_new (GST_TYPE_PAD,
501 "name", name, "direction", templ->direction, "template", templ, NULL);
505 * gst_pad_new_from_static_template:
506 * @templ: the #GstStaticPadTemplate to use
507 * @name: the name of the element
509 * Creates a new pad with the given name from the given static template.
510 * If name is NULL, a guaranteed unique name (across all pads)
512 * This function makes a copy of the name so you can safely free the name.
514 * Returns: a new #GstPad, or NULL in case of an error.
517 gst_pad_new_from_static_template (GstStaticPadTemplate * templ,
521 GstPadTemplate *template;
523 template = gst_static_pad_template_get (templ);
524 pad = gst_pad_new_from_template (template, name);
525 gst_object_unref (template);
530 * gst_pad_get_direction:
531 * @pad: a #GstPad to get the direction of.
533 * Gets the direction of the pad. The direction of the pad is
534 * decided at construction time so this function does not take
537 * Returns: the #GstPadDirection of the pad.
542 gst_pad_get_direction (GstPad * pad)
544 GstPadDirection result;
546 /* PAD_UNKNOWN is a little silly but we need some sort of
547 * error return value */
548 g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
550 GST_OBJECT_LOCK (pad);
551 result = GST_PAD_DIRECTION (pad);
552 GST_OBJECT_UNLOCK (pad);
558 gst_pad_activate_default (GstPad * pad)
560 return gst_pad_activate_push (pad, TRUE);
564 pre_activate (GstPad * pad, GstActivateMode new_mode)
567 case GST_ACTIVATE_PUSH:
568 case GST_ACTIVATE_PULL:
569 GST_OBJECT_LOCK (pad);
570 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d, unset flushing",
572 GST_PAD_UNSET_FLUSHING (pad);
573 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
574 GST_OBJECT_UNLOCK (pad);
576 case GST_ACTIVATE_NONE:
577 GST_OBJECT_LOCK (pad);
578 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE NONE, set flushing",
580 GST_PAD_SET_FLUSHING (pad);
581 /* unlock blocked pads so element can resume and stop */
582 GST_PAD_BLOCK_SIGNAL (pad);
583 GST_OBJECT_UNLOCK (pad);
589 post_activate (GstPad * pad, GstActivateMode new_mode)
592 case GST_ACTIVATE_PUSH:
593 case GST_ACTIVATE_PULL:
596 case GST_ACTIVATE_NONE:
597 /* ensures that streaming stops */
598 GST_PAD_STREAM_LOCK (pad);
599 /* while we're at it set activation mode */
600 GST_OBJECT_LOCK (pad);
601 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d", new_mode);
602 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
603 GST_OBJECT_UNLOCK (pad);
604 GST_PAD_STREAM_UNLOCK (pad);
610 * gst_pad_set_active:
611 * @pad: the #GstPad to activate or deactivate.
612 * @active: whether or not the pad should be active.
614 * Activates or deactivates the given pad.
615 * Normally called from within core state change functions.
617 * If @active, makes sure the pad is active. If it is already active, either in
618 * push or pull mode, just return. Otherwise dispatches to the pad's activate
619 * function to perform the actual activation.
621 * If not @active, checks the pad's current mode and calls
622 * gst_pad_activate_push() or gst_pad_activate_pull(), as appropriate, with a
625 * Returns: #TRUE if the operation was successful.
630 gst_pad_set_active (GstPad * pad, gboolean active)
633 gboolean ret = FALSE;
635 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
637 GST_OBJECT_LOCK (pad);
638 old = GST_PAD_ACTIVATE_MODE (pad);
639 GST_OBJECT_UNLOCK (pad);
643 case GST_ACTIVATE_PUSH:
644 case GST_ACTIVATE_PULL:
647 case GST_ACTIVATE_NONE:
648 ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
653 case GST_ACTIVATE_PUSH:
654 ret = gst_pad_activate_push (pad, FALSE);
656 case GST_ACTIVATE_PULL:
657 ret = gst_pad_activate_pull (pad, FALSE);
659 case GST_ACTIVATE_NONE:
665 if (!active && !ret) {
666 GST_OBJECT_LOCK (pad);
667 g_critical ("Failed to deactivate pad %s:%s, very bad",
668 GST_DEBUG_PAD_NAME (pad));
669 GST_OBJECT_UNLOCK (pad);
676 * gst_pad_activate_pull:
677 * @pad: the #GstPad to activate or deactivate.
678 * @active: whether or not the pad should be active.
680 * Activates or deactivates the given pad in pull mode via dispatching to the
681 * pad's activatepullfunc. For use from within pad activation functions only.
682 * When called on sink pads, will first proxy the call to the peer pad, which is
683 * expected to activate its internally linked pads from within its activate_pull
686 * If you don't know what this is, you probably don't want to call it.
688 * Returns: TRUE if the operation was successful.
693 gst_pad_activate_pull (GstPad * pad, gboolean active)
695 GstActivateMode old, new;
698 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
700 GST_OBJECT_LOCK (pad);
701 old = GST_PAD_ACTIVATE_MODE (pad);
702 GST_OBJECT_UNLOCK (pad);
706 case GST_ACTIVATE_PULL:
708 case GST_ACTIVATE_PUSH:
709 /* pad was activate in the wrong direction, deactivate it
710 * and reactivate it in pull mode */
711 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
712 goto deactivate_failed;
713 /* fallthrough, pad is deactivated now. */
714 case GST_ACTIVATE_NONE:
719 case GST_ACTIVATE_NONE:
721 case GST_ACTIVATE_PUSH:
722 /* pad was activated in the other direction, deactivate it
723 * in push mode, this should not happen... */
724 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
725 goto deactivate_failed;
726 /* everything is fine now */
728 case GST_ACTIVATE_PULL:
733 if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
734 if ((peer = gst_pad_get_peer (pad))) {
735 if (G_UNLIKELY (!gst_pad_activate_pull (peer, active)))
737 gst_object_unref (peer);
740 if (G_UNLIKELY (GST_PAD_GETRANGEFUNC (pad) == NULL))
741 goto failure; /* Can't activate pull on a src without a
745 new = active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
746 pre_activate (pad, new);
748 if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
749 if (G_UNLIKELY (!GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active)))
752 /* can happen for sinks of passthrough elements */
755 post_activate (pad, new);
757 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
758 active ? "activated" : "deactivated");
764 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
765 active ? "activated" : "deactivated");
770 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
771 "failed to %s in switch to pull from mode %d",
772 (active ? "activate" : "deactivate"), old);
777 GST_OBJECT_LOCK (peer);
778 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
779 "activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
780 GST_OBJECT_UNLOCK (peer);
781 gst_object_unref (peer);
786 GST_OBJECT_LOCK (pad);
787 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
788 active ? "activate" : "deactivate");
789 GST_PAD_SET_FLUSHING (pad);
790 GST_PAD_ACTIVATE_MODE (pad) = old;
791 GST_OBJECT_UNLOCK (pad);
797 * gst_pad_activate_push:
798 * @pad: the #GstPad to activate or deactivate.
799 * @active: whether the pad should be active or not.
801 * Activates or deactivates the given pad in push mode via dispatching to the
802 * pad's activatepushfunc. For use from within pad activation functions only.
804 * If you don't know what this is, you probably don't want to call it.
806 * Returns: %TRUE if the operation was successful.
811 gst_pad_activate_push (GstPad * pad, gboolean active)
813 GstActivateMode old, new;
815 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
816 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
817 active ? "activated" : "deactivated");
819 GST_OBJECT_LOCK (pad);
820 old = GST_PAD_ACTIVATE_MODE (pad);
821 GST_OBJECT_UNLOCK (pad);
825 case GST_ACTIVATE_PUSH:
827 case GST_ACTIVATE_PULL:
828 /* pad was activate in the wrong direction, deactivate it
829 * an reactivate it in push mode */
830 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
831 goto deactivate_failed;
832 /* fallthrough, pad is deactivated now. */
833 case GST_ACTIVATE_NONE:
838 case GST_ACTIVATE_NONE:
840 case GST_ACTIVATE_PULL:
841 /* pad was activated in the other direction, deactivate it
842 * in pull mode, this should not happen... */
843 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
844 goto deactivate_failed;
845 /* everything is fine now */
847 case GST_ACTIVATE_PUSH:
852 new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
853 pre_activate (pad, new);
855 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
856 if (G_UNLIKELY (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active))) {
860 /* quite ok, element relies on state change func to prepare itself */
863 post_activate (pad, new);
865 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
866 active ? "activated" : "deactivated");
871 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
872 active ? "activated" : "deactivated");
877 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
878 "failed to %s in switch to push from mode %d",
879 (active ? "activate" : "deactivate"), old);
884 GST_OBJECT_LOCK (pad);
885 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
886 active ? "activate" : "deactivate");
887 GST_PAD_SET_FLUSHING (pad);
888 GST_PAD_ACTIVATE_MODE (pad) = old;
889 GST_OBJECT_UNLOCK (pad);
896 * @pad: the #GstPad to query
898 * Query if a pad is active
900 * Returns: TRUE if the pad is active.
905 gst_pad_is_active (GstPad * pad)
907 gboolean result = FALSE;
909 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
911 GST_OBJECT_LOCK (pad);
912 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
913 GST_OBJECT_UNLOCK (pad);
919 * gst_pad_set_blocked_async:
920 * @pad: the #GstPad to block or unblock
921 * @blocked: boolean indicating whether the pad should be blocked or unblocked
922 * @callback: #GstPadBlockCallback that will be called when the
924 * @user_data: user data passed to the callback
926 * Blocks or unblocks the dataflow on a pad. The provided callback
927 * is called when the operation succeeds; this happens right before the next
928 * attempt at pushing a buffer on the pad.
930 * This can take a while as the pad can only become blocked when real dataflow
932 * When the pipeline is stalled, for example in PAUSED, this can
933 * take an indeterminate amount of time.
934 * You can pass NULL as the callback to make this call block. Be careful with
935 * this blocking call as it might not return for reasons stated above.
937 * Returns: TRUE if the pad could be blocked. This function can fail
938 * if wrong parameters were passed or the pad was already in the
944 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
945 GstPadBlockCallback callback, gpointer user_data)
947 gboolean was_blocked = FALSE;
949 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
951 GST_OBJECT_LOCK (pad);
953 was_blocked = GST_PAD_IS_BLOCKED (pad);
955 if (G_UNLIKELY (was_blocked == blocked))
956 goto had_right_state;
959 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
961 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
962 pad->block_callback = callback;
963 pad->block_data = user_data;
965 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
966 GST_PAD_BLOCK_WAIT (pad);
967 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
970 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
972 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
974 pad->block_callback = callback;
975 pad->block_data = user_data;
978 GST_PAD_BLOCK_SIGNAL (pad);
980 GST_PAD_BLOCK_SIGNAL (pad);
981 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
982 GST_PAD_BLOCK_WAIT (pad);
983 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
986 GST_OBJECT_UNLOCK (pad);
992 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
993 "pad was in right state (%d)", was_blocked);
994 GST_OBJECT_UNLOCK (pad);
1001 * gst_pad_set_blocked:
1002 * @pad: the #GstPad to block or unblock
1003 * @blocked: boolean indicating we should block or unblock
1005 * Blocks or unblocks the dataflow on a pad. This function is
1006 * a shortcut for gst_pad_set_blocked_async() with a NULL
1009 * Returns: TRUE if the pad could be blocked. This function can fail
1010 * wrong parameters were passed or the pad was already in the
1016 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
1018 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
1022 * gst_pad_is_blocked:
1023 * @pad: the #GstPad to query
1025 * Checks if the pad is blocked or not. This function returns the
1026 * last requested state of the pad. It is not certain that the pad
1027 * is actually blocked at this point.
1029 * Returns: TRUE if the pad is blocked.
1034 gst_pad_is_blocked (GstPad * pad)
1036 gboolean result = FALSE;
1038 g_return_val_if_fail (GST_IS_PAD (pad), result);
1040 GST_OBJECT_LOCK (pad);
1041 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
1042 GST_OBJECT_UNLOCK (pad);
1048 * gst_pad_set_activate_function:
1050 * @activate: the #GstPadActivateFunction to set.
1052 * Sets the given activate function for @pad. The activate function will
1053 * dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
1054 * the actual activation. Only makes sense to set on sink pads.
1056 * Call this function if your sink pad can start a pull-based task.
1059 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
1061 g_return_if_fail (GST_IS_PAD (pad));
1063 GST_PAD_ACTIVATEFUNC (pad) = activate;
1064 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
1065 GST_DEBUG_FUNCPTR_NAME (activate));
1069 * gst_pad_set_activatepull_function:
1071 * @activatepull: the #GstPadActivateModeFunction to set.
1073 * Sets the given activate_pull function for the pad. An activate_pull function
1074 * prepares the element and any upstream connections for pulling. See XXX
1075 * part-activation.txt for details.
1078 gst_pad_set_activatepull_function (GstPad * pad,
1079 GstPadActivateModeFunction activatepull)
1081 g_return_if_fail (GST_IS_PAD (pad));
1083 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
1084 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
1085 GST_DEBUG_FUNCPTR_NAME (activatepull));
1089 * gst_pad_set_activatepush_function:
1091 * @activatepush: the #GstPadActivateModeFunction to set.
1093 * Sets the given activate_push function for the pad. An activate_push function
1094 * prepares the element for pushing. See XXX part-activation.txt for details.
1097 gst_pad_set_activatepush_function (GstPad * pad,
1098 GstPadActivateModeFunction activatepush)
1100 g_return_if_fail (GST_IS_PAD (pad));
1102 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1103 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
1104 GST_DEBUG_FUNCPTR_NAME (activatepush));
1108 * gst_pad_set_chain_function:
1109 * @pad: a sink #GstPad.
1110 * @chain: the #GstPadChainFunction to set.
1112 * Sets the given chain function for the pad. The chain function is called to
1113 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1116 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1118 g_return_if_fail (GST_IS_PAD (pad));
1119 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
1121 GST_PAD_CHAINFUNC (pad) = chain;
1122 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
1123 GST_DEBUG_FUNCPTR_NAME (chain));
1127 * gst_pad_set_getrange_function:
1128 * @pad: a source #GstPad.
1129 * @get: the #GstPadGetRangeFunction to set.
1131 * Sets the given getrange function for the pad. The getrange function is called to
1132 * produce a new #GstBuffer to start the processing pipeline. see
1133 * #GstPadGetRangeFunction for a description of the getrange function.
1136 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1138 g_return_if_fail (GST_IS_PAD (pad));
1139 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1141 GST_PAD_GETRANGEFUNC (pad) = get;
1143 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
1144 GST_DEBUG_FUNCPTR_NAME (get));
1148 * gst_pad_set_checkgetrange_function:
1149 * @pad: a source #GstPad.
1150 * @check: the #GstPadCheckGetRangeFunction to set.
1152 * Sets the given checkgetrange function for the pad. Implement this function on
1153 * a pad if you dynamically support getrange based scheduling on the pad.
1156 gst_pad_set_checkgetrange_function (GstPad * pad,
1157 GstPadCheckGetRangeFunction check)
1159 g_return_if_fail (GST_IS_PAD (pad));
1160 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1162 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1164 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
1165 GST_DEBUG_FUNCPTR_NAME (check));
1169 * gst_pad_set_event_function:
1170 * @pad: a source #GstPad.
1171 * @event: the #GstPadEventFunction to set.
1173 * Sets the given event handler for the pad.
1176 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1178 g_return_if_fail (GST_IS_PAD (pad));
1180 GST_PAD_EVENTFUNC (pad) = event;
1182 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
1183 GST_DEBUG_FUNCPTR_NAME (event));
1187 * gst_pad_set_query_function:
1188 * @pad: a #GstPad of either direction.
1189 * @query: the #GstPadQueryFunction to set.
1191 * Set the given query function for the pad.
1194 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1196 g_return_if_fail (GST_IS_PAD (pad));
1198 GST_PAD_QUERYFUNC (pad) = query;
1200 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
1201 GST_DEBUG_FUNCPTR_NAME (query));
1205 * gst_pad_set_query_type_function:
1206 * @pad: a #GstPad of either direction.
1207 * @type_func: the #GstPadQueryTypeFunction to set.
1209 * Set the given query type function for the pad.
1212 gst_pad_set_query_type_function (GstPad * pad,
1213 GstPadQueryTypeFunction type_func)
1215 g_return_if_fail (GST_IS_PAD (pad));
1217 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1219 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
1220 GST_DEBUG_FUNCPTR_NAME (type_func));
1224 * gst_pad_get_query_types:
1227 * Get an array of supported queries that can be performed
1230 * Returns: a zero-terminated array of #GstQueryType.
1232 const GstQueryType *
1233 gst_pad_get_query_types (GstPad * pad)
1235 GstPadQueryTypeFunction func;
1237 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1239 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1251 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1253 *data = gst_pad_get_query_types (pad);
1259 * gst_pad_get_query_types_default:
1262 * Invoke the default dispatcher for the query types on
1265 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1266 * internally-linked pads has a query types function.
1268 const GstQueryType *
1269 gst_pad_get_query_types_default (GstPad * pad)
1271 GstQueryType *result = NULL;
1273 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1275 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1276 gst_pad_get_query_types_dispatcher, &result);
1282 * gst_pad_set_internal_link_function:
1283 * @pad: a #GstPad of either direction.
1284 * @intlink: the #GstPadIntLinkFunction to set.
1286 * Sets the given internal link function for the pad.
1289 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1291 g_return_if_fail (GST_IS_PAD (pad));
1293 GST_PAD_INTLINKFUNC (pad) = intlink;
1294 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
1295 GST_DEBUG_FUNCPTR_NAME (intlink));
1299 * gst_pad_set_link_function:
1301 * @link: the #GstPadLinkFunction to set.
1303 * Sets the given link function for the pad. It will be called when
1304 * the pad is linked with another pad.
1306 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1309 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1310 * cannot be made for some reason.
1312 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1313 * of the peer sink pad, if present.
1316 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1318 g_return_if_fail (GST_IS_PAD (pad));
1320 GST_PAD_LINKFUNC (pad) = link;
1321 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
1322 GST_DEBUG_FUNCPTR_NAME (link));
1326 * gst_pad_set_unlink_function:
1328 * @unlink: the #GstPadUnlinkFunction to set.
1330 * Sets the given unlink function for the pad. It will be called
1331 * when the pad is unlinked.
1334 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1336 g_return_if_fail (GST_IS_PAD (pad));
1338 GST_PAD_UNLINKFUNC (pad) = unlink;
1339 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
1340 GST_DEBUG_FUNCPTR_NAME (unlink));
1344 * gst_pad_set_getcaps_function:
1346 * @getcaps: the #GstPadGetCapsFunction to set.
1348 * Sets the given getcaps function for the pad. @getcaps should return the
1349 * allowable caps for a pad in the context of the element's state, its link to
1350 * other elements, and the devices or files it has opened. These caps must be a
1351 * subset of the pad template caps. In the NULL state with no links, @getcaps
1352 * should ideally return the same caps as the pad template. In rare
1353 * circumstances, an object property can affect the caps returned by @getcaps,
1354 * but this is discouraged.
1356 * You do not need to call this function if @pad's allowed caps are always the
1357 * same as the pad template caps. This can only be true if the padtemplate
1358 * has fixed simple caps.
1360 * For most filters, the caps returned by @getcaps is directly affected by the
1361 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1362 * the srcpad's getcaps function is directly related to the stream data. Again,
1363 * @getcaps should return the most specific caps it reasonably can, since this
1364 * helps with autoplugging.
1366 * Note that the return value from @getcaps is owned by the caller, so the caller
1367 * should unref the caps after usage.
1370 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1372 g_return_if_fail (GST_IS_PAD (pad));
1374 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1375 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
1376 GST_DEBUG_FUNCPTR_NAME (getcaps));
1380 * gst_pad_set_acceptcaps_function:
1382 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1384 * Sets the given acceptcaps function for the pad. The acceptcaps function
1385 * will be called to check if the pad can accept the given caps. Setting the
1386 * acceptcaps function to NULL restores the default behaviour of allowing
1387 * any caps that matches the caps from gst_pad_get_caps.
1390 gst_pad_set_acceptcaps_function (GstPad * pad,
1391 GstPadAcceptCapsFunction acceptcaps)
1393 g_return_if_fail (GST_IS_PAD (pad));
1395 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1396 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
1397 GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1401 * gst_pad_set_fixatecaps_function:
1403 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1405 * Sets the given fixatecaps function for the pad. The fixatecaps function
1406 * will be called whenever the default values for a GstCaps needs to be
1410 gst_pad_set_fixatecaps_function (GstPad * pad,
1411 GstPadFixateCapsFunction fixatecaps)
1413 g_return_if_fail (GST_IS_PAD (pad));
1415 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1416 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
1417 GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1421 * gst_pad_set_setcaps_function:
1423 * @setcaps: the #GstPadSetCapsFunction to set.
1425 * Sets the given setcaps function for the pad. The setcaps function
1426 * will be called whenever a buffer with a new media type is pushed or
1427 * pulled from the pad. The pad/element needs to update its internal
1428 * structures to process the new media type. If this new type is not
1429 * acceptable, the setcaps function should return FALSE.
1432 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1434 g_return_if_fail (GST_IS_PAD (pad));
1436 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1437 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
1438 GST_DEBUG_FUNCPTR_NAME (setcaps));
1442 * gst_pad_set_bufferalloc_function:
1443 * @pad: a sink #GstPad.
1444 * @bufalloc: the #GstPadBufferAllocFunction to set.
1446 * Sets the given bufferalloc function for the pad. Note that the
1447 * bufferalloc function can only be set on sinkpads.
1450 gst_pad_set_bufferalloc_function (GstPad * pad,
1451 GstPadBufferAllocFunction bufalloc)
1453 g_return_if_fail (GST_IS_PAD (pad));
1454 g_return_if_fail (GST_PAD_IS_SINK (pad));
1456 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1457 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
1458 GST_DEBUG_FUNCPTR_NAME (bufalloc));
1463 * @srcpad: the source #GstPad to unlink.
1464 * @sinkpad: the sink #GstPad to unlink.
1466 * Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
1469 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1470 * the pads were not linked together.
1475 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1477 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1478 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1480 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1481 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1482 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1484 GST_OBJECT_LOCK (srcpad);
1486 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1489 GST_OBJECT_LOCK (sinkpad);
1491 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1494 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1495 goto not_linked_together;
1497 if (GST_PAD_UNLINKFUNC (srcpad)) {
1498 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1500 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1501 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1504 /* first clear peers */
1505 GST_PAD_PEER (srcpad) = NULL;
1506 GST_PAD_PEER (sinkpad) = NULL;
1508 GST_OBJECT_UNLOCK (sinkpad);
1509 GST_OBJECT_UNLOCK (srcpad);
1511 /* fire off a signal to each of the pads telling them
1512 * that they've been unlinked */
1513 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1514 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1516 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1517 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1523 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1524 GST_OBJECT_UNLOCK (srcpad);
1529 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1530 GST_OBJECT_UNLOCK (sinkpad);
1531 GST_OBJECT_UNLOCK (srcpad);
1534 not_linked_together:
1536 /* we do not emit a warning in this case because unlinking cannot
1537 * be made MT safe.*/
1538 GST_OBJECT_UNLOCK (sinkpad);
1539 GST_OBJECT_UNLOCK (srcpad);
1545 * gst_pad_is_linked:
1546 * @pad: pad to check
1548 * Checks if a @pad is linked to another pad or not.
1550 * Returns: TRUE if the pad is linked, FALSE otherwise.
1555 gst_pad_is_linked (GstPad * pad)
1559 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1561 GST_OBJECT_LOCK (pad);
1562 result = (GST_PAD_PEER (pad) != NULL);
1563 GST_OBJECT_UNLOCK (pad);
1568 /* get the caps from both pads and see if the intersection
1571 * This function should be called with the pad LOCK on both
1575 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1581 srccaps = gst_pad_get_caps_unlocked (src);
1582 sinkcaps = gst_pad_get_caps_unlocked (sink);
1584 GST_CAT_DEBUG (GST_CAT_CAPS, "src caps %" GST_PTR_FORMAT, srccaps);
1585 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1587 /* if we have caps on both pads we can check the intersection. If one
1588 * of the caps is NULL, we return TRUE. */
1589 if (srccaps == NULL || sinkcaps == NULL)
1592 icaps = gst_caps_intersect (srccaps, sinkcaps);
1593 gst_caps_unref (srccaps);
1594 gst_caps_unref (sinkcaps);
1599 GST_CAT_DEBUG (GST_CAT_CAPS,
1600 "intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
1602 if (gst_caps_is_empty (icaps))
1605 gst_caps_unref (icaps);
1610 /* incompatible cases */
1613 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection gave NULL");
1618 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is EMPTY");
1619 gst_caps_unref (icaps);
1624 /* check if the grandparents of both pads are the same.
1625 * This check is required so that we don't try to link
1626 * pads from elements in different bins without ghostpads.
1628 * The LOCK should be held on both pads
1631 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1633 GstObject *psrc, *psink;
1634 gboolean res = TRUE;
1636 psrc = GST_OBJECT_PARENT (src);
1637 psink = GST_OBJECT_PARENT (sink);
1639 /* if one of the pads has no parent, we allow the link */
1640 if (psrc && psink) {
1641 /* if the parents are the same, we have a loop */
1642 if (G_UNLIKELY (psrc == psink))
1645 /* if they both have a parent, we check the grandparents */
1646 psrc = gst_object_get_parent (psrc);
1647 psink = gst_object_get_parent (psink);
1649 if (G_UNLIKELY (psrc != psink)) {
1650 /* if they have grandparents but they are not the same */
1651 GST_CAT_DEBUG (GST_CAT_CAPS,
1652 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1653 GST_PTR_FORMAT, psrc, psink);
1657 gst_object_unref (psrc);
1659 gst_object_unref (psink);
1667 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1674 /* FIXME leftover from an attempt at refactoring... */
1675 /* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
1676 * the two pads will be locked in the srcpad, sinkpad order. */
1677 static GstPadLinkReturn
1678 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1680 /* generic checks */
1681 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
1682 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
1684 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1685 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1687 GST_OBJECT_LOCK (srcpad);
1689 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1692 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1693 goto src_was_linked;
1695 GST_OBJECT_LOCK (sinkpad);
1697 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1700 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1701 goto sink_was_linked;
1703 /* check hierarchy, pads can only be linked if the grandparents
1705 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1706 goto wrong_hierarchy;
1708 /* check pad caps for non-empty intersection */
1709 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1712 /* FIXME check pad scheduling for non-empty intersection */
1714 return GST_PAD_LINK_OK;
1718 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1719 GST_OBJECT_UNLOCK (srcpad);
1720 return GST_PAD_LINK_WRONG_DIRECTION;
1724 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
1725 GST_DEBUG_PAD_NAME (srcpad),
1726 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1727 /* we do not emit a warning in this case because unlinking cannot
1728 * be made MT safe.*/
1729 GST_OBJECT_UNLOCK (srcpad);
1730 return GST_PAD_LINK_WAS_LINKED;
1734 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1735 GST_OBJECT_UNLOCK (sinkpad);
1736 GST_OBJECT_UNLOCK (srcpad);
1737 return GST_PAD_LINK_WRONG_DIRECTION;
1741 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
1742 GST_DEBUG_PAD_NAME (sinkpad),
1743 GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
1744 /* we do not emit a warning in this case because unlinking cannot
1745 * be made MT safe.*/
1746 GST_OBJECT_UNLOCK (sinkpad);
1747 GST_OBJECT_UNLOCK (srcpad);
1748 return GST_PAD_LINK_WAS_LINKED;
1752 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1753 GST_OBJECT_UNLOCK (sinkpad);
1754 GST_OBJECT_UNLOCK (srcpad);
1755 return GST_PAD_LINK_WRONG_HIERARCHY;
1759 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1760 GST_OBJECT_UNLOCK (sinkpad);
1761 GST_OBJECT_UNLOCK (srcpad);
1762 return GST_PAD_LINK_NOFORMAT;
1768 * @srcpad: the source #GstPad to link.
1769 * @sinkpad: the sink #GstPad to link.
1771 * Links the source pad and the sink pad.
1773 * Returns: A result code indicating if the connection worked or
1779 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1781 GstPadLinkReturn result;
1783 /* prepare will also lock the two pads */
1784 result = gst_pad_link_prepare (srcpad, sinkpad);
1786 if (result != GST_PAD_LINK_OK)
1787 goto prepare_failed;
1789 /* must set peers before calling the link function */
1790 GST_PAD_PEER (srcpad) = sinkpad;
1791 GST_PAD_PEER (sinkpad) = srcpad;
1793 GST_OBJECT_UNLOCK (sinkpad);
1794 GST_OBJECT_UNLOCK (srcpad);
1796 /* FIXME released the locks here, concurrent thread might link
1797 * something else. */
1798 if (GST_PAD_LINKFUNC (srcpad)) {
1799 /* this one will call the peer link function */
1800 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
1801 } else if (GST_PAD_LINKFUNC (sinkpad)) {
1802 /* if no source link function, we need to call the sink link
1803 * function ourselves. */
1804 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
1806 result = GST_PAD_LINK_OK;
1809 GST_OBJECT_LOCK (srcpad);
1810 GST_OBJECT_LOCK (sinkpad);
1812 if (result == GST_PAD_LINK_OK) {
1813 GST_OBJECT_UNLOCK (sinkpad);
1814 GST_OBJECT_UNLOCK (srcpad);
1816 /* fire off a signal to each of the pads telling them
1817 * that they've been linked */
1818 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
1819 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
1821 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
1822 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1824 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
1825 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1827 GST_PAD_PEER (srcpad) = NULL;
1828 GST_PAD_PEER (sinkpad) = NULL;
1830 GST_OBJECT_UNLOCK (sinkpad);
1831 GST_OBJECT_UNLOCK (srcpad);
1842 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
1844 GstPadTemplate **template_p;
1846 /* this function would need checks if it weren't static */
1848 GST_OBJECT_LOCK (pad);
1849 template_p = &pad->padtemplate;
1850 gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
1851 GST_OBJECT_UNLOCK (pad);
1854 gst_pad_template_pad_created (templ, pad);
1858 * gst_pad_get_pad_template:
1861 * Gets the template for @pad.
1863 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
1864 * if this pad has no template.
1866 * FIXME: currently returns an unrefcounted padtemplate.
1869 gst_pad_get_pad_template (GstPad * pad)
1871 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1873 return GST_PAD_PAD_TEMPLATE (pad);
1877 /* should be called with the pad LOCK held */
1878 /* refs the caps, so caller is responsible for getting it unreffed */
1880 gst_pad_get_caps_unlocked (GstPad * pad)
1882 GstCaps *result = NULL;
1884 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
1886 if (GST_PAD_GETCAPSFUNC (pad)) {
1887 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1888 "dispatching to pad getcaps function");
1890 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
1891 GST_OBJECT_UNLOCK (pad);
1892 result = GST_PAD_GETCAPSFUNC (pad) (pad);
1893 GST_OBJECT_LOCK (pad);
1894 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
1896 if (result == NULL) {
1897 g_critical ("pad %s:%s returned NULL caps from getcaps function",
1898 GST_DEBUG_PAD_NAME (pad));
1900 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1901 "pad getcaps returned %" GST_PTR_FORMAT, result);
1902 #ifndef G_DISABLE_ASSERT
1903 /* check that the returned caps are a real subset of the template caps */
1904 if (GST_PAD_PAD_TEMPLATE (pad)) {
1905 const GstCaps *templ_caps =
1906 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
1907 if (!gst_caps_is_subset (result, templ_caps)) {
1910 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
1911 "pad returned caps %" GST_PTR_FORMAT
1912 " which are not a real subset of its template caps %"
1913 GST_PTR_FORMAT, result, templ_caps);
1915 ("pad %s:%s returned caps that are not a real subset of its template caps",
1916 GST_DEBUG_PAD_NAME (pad));
1917 temp = gst_caps_intersect (templ_caps, result);
1918 gst_caps_unref (result);
1926 if (GST_PAD_PAD_TEMPLATE (pad)) {
1927 GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
1929 result = GST_PAD_TEMPLATE_CAPS (templ);
1930 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1931 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
1934 result = gst_caps_ref (result);
1937 if (GST_PAD_CAPS (pad)) {
1938 result = GST_PAD_CAPS (pad);
1940 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1941 "using pad caps %p %" GST_PTR_FORMAT, result, result);
1943 result = gst_caps_ref (result);
1947 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
1948 result = gst_caps_new_empty ();
1956 * @pad: a #GstPad to get the capabilities of.
1958 * Gets the capabilities this pad can produce or consume.
1959 * Note that this method doesn't necessarily return the caps set by
1960 * gst_pad_set_caps() - use #GST_PAD_CAPS for that instead.
1961 * gst_pad_get_caps returns all possible caps a pad can operate with, using
1962 * the pad's get_caps function;
1963 * this returns the pad template caps if not explicitly set.
1965 * Returns: a newly allocated copy of the #GstCaps of this pad.
1970 gst_pad_get_caps (GstPad * pad)
1972 GstCaps *result = NULL;
1974 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1976 GST_OBJECT_LOCK (pad);
1978 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
1980 result = gst_pad_get_caps_unlocked (pad);
1981 GST_OBJECT_UNLOCK (pad);
1987 * gst_pad_peer_get_caps:
1988 * @pad: a #GstPad to get the peer capabilities of.
1990 * Gets the capabilities of the peer connected to this pad.
1992 * Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
1993 * gst_caps_unref to get rid of it. this function returns NULL if there is no
1997 gst_pad_peer_get_caps (GstPad * pad)
2000 GstCaps *result = NULL;
2002 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2004 GST_OBJECT_LOCK (pad);
2006 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2008 peerpad = GST_PAD_PEER (pad);
2009 if (G_UNLIKELY (peerpad == NULL))
2012 gst_object_ref (peerpad);
2013 GST_OBJECT_UNLOCK (pad);
2015 result = gst_pad_get_caps (peerpad);
2017 gst_object_unref (peerpad);
2023 GST_OBJECT_UNLOCK (pad);
2029 fixate_value (GValue * dest, const GValue * src)
2031 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
2032 g_value_init (dest, G_TYPE_INT);
2033 g_value_set_int (dest, gst_value_get_int_range_min (src));
2034 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
2035 g_value_init (dest, G_TYPE_DOUBLE);
2036 g_value_set_double (dest, gst_value_get_double_range_min (src));
2037 } else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
2038 gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
2039 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
2040 GValue temp = { 0 };
2042 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
2043 if (!fixate_value (dest, &temp))
2044 gst_value_init_and_copy (dest, &temp);
2045 g_value_unset (&temp);
2046 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
2047 gboolean res = FALSE;
2050 g_value_init (dest, GST_TYPE_ARRAY);
2051 for (n = 0; n < gst_value_array_get_size (src); n++) {
2053 const GValue *orig_kid = gst_value_array_get_value (src, n);
2055 if (!fixate_value (&kid, orig_kid))
2056 gst_value_init_and_copy (&kid, orig_kid);
2059 gst_value_array_append_value (dest, &kid);
2060 g_value_unset (&kid);
2064 g_value_unset (dest);
2075 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
2077 GstStructure *s = data;
2080 if (fixate_value (&v, value)) {
2081 gst_structure_id_set_value (s, field_id, &v);
2089 * gst_pad_fixate_caps:
2090 * @pad: a #GstPad to fixate
2091 * @caps: the #GstCaps to fixate
2093 * Fixate a caps on the given pad. Modifies the caps in place, so you should
2094 * make sure that the caps are actually writable (see gst_caps_make_writable()).
2097 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
2099 GstPadFixateCapsFunction fixatefunc;
2102 g_return_if_fail (GST_IS_PAD (pad));
2103 g_return_if_fail (caps != NULL);
2105 if (gst_caps_is_fixed (caps))
2108 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
2110 fixatefunc (pad, caps);
2113 /* default fixation */
2114 for (n = 0; n < gst_caps_get_size (caps); n++) {
2115 GstStructure *s = gst_caps_get_structure (caps, n);
2117 gst_structure_foreach (s, gst_pad_default_fixate, s);
2121 /* Default accept caps implementation just checks against
2122 * against the allowed caps for the pad */
2124 gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
2126 /* get the caps and see if it intersects to something
2130 gboolean result = FALSE;
2132 allowed = gst_pad_get_caps (pad);
2134 intersect = gst_caps_intersect (allowed, caps);
2136 result = !gst_caps_is_empty (intersect);
2138 gst_caps_unref (allowed);
2139 gst_caps_unref (intersect);
2146 * gst_pad_accept_caps:
2147 * @pad: a #GstPad to check
2148 * @caps: a #GstCaps to check on the pad
2150 * Check if the given pad accepts the caps.
2152 * Returns: TRUE if the pad can accept the caps.
2155 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2158 GstPadAcceptCapsFunction acceptfunc;
2159 GstCaps *existing = NULL;
2161 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2163 /* any pad can be unnegotiated */
2167 /* lock for checking the existing caps */
2168 GST_OBJECT_LOCK (pad);
2169 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2170 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
2171 /* The current caps on a pad are trivially acceptable */
2172 if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
2173 if (caps == existing || gst_caps_is_equal (caps, existing))
2176 GST_OBJECT_UNLOCK (pad);
2178 if (G_LIKELY (acceptfunc)) {
2179 /* we can call the function */
2180 result = acceptfunc (pad, caps);
2182 /* Only null if the element explicitly unset it */
2183 result = gst_pad_acceptcaps_default (pad, caps);
2189 GST_OBJECT_UNLOCK (pad);
2195 * gst_pad_peer_accept_caps:
2196 * @pad: a #GstPad to check the peer of
2197 * @caps: a #GstCaps to check on the pad
2199 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2202 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2205 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2210 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2212 GST_OBJECT_LOCK (pad);
2214 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
2216 peerpad = GST_PAD_PEER (pad);
2217 if (G_UNLIKELY (peerpad == NULL))
2220 result = gst_pad_accept_caps (peerpad, caps);
2221 GST_OBJECT_UNLOCK (pad);
2227 GST_OBJECT_UNLOCK (pad);
2234 * @pad: a #GstPad to set the capabilities of.
2235 * @caps: a #GstCaps to set.
2237 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2238 * caps on the pad will be unreffed. This function refs the caps so you should
2239 * unref if as soon as you don't need it anymore.
2240 * It is possible to set NULL caps, which will make the pad unnegotiated
2243 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2244 * or bad parameters were provided to this function.
2249 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2251 GstPadSetCapsFunction setcaps;
2254 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2255 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2257 GST_OBJECT_LOCK (pad);
2258 existing = GST_PAD_CAPS (pad);
2259 if (existing == caps)
2262 if (gst_caps_is_equal (caps, existing))
2263 goto setting_same_caps;
2265 setcaps = GST_PAD_SETCAPSFUNC (pad);
2267 /* call setcaps function to configure the pad only if the
2268 * caps is not NULL */
2269 if (setcaps != NULL && caps) {
2270 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2271 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2272 GST_OBJECT_UNLOCK (pad);
2273 if (!setcaps (pad, caps))
2275 GST_OBJECT_LOCK (pad);
2276 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2278 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
2282 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2283 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %" GST_PTR_FORMAT, caps);
2284 GST_OBJECT_UNLOCK (pad);
2286 g_object_notify (G_OBJECT (pad), "caps");
2292 GST_OBJECT_UNLOCK (pad);
2297 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2298 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2299 "caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
2300 GST_OBJECT_UNLOCK (pad);
2307 GST_OBJECT_LOCK (pad);
2308 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2309 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2310 "caps %" GST_PTR_FORMAT " could not be set", caps);
2311 GST_OBJECT_UNLOCK (pad);
2318 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2320 GstPadSetCapsFunction setcaps;
2323 setcaps = GST_PAD_SETCAPSFUNC (pad);
2325 /* See if pad accepts the caps - only needed if
2326 * no setcaps function */
2327 if (setcaps == NULL)
2328 if (!gst_pad_accept_caps (pad, caps))
2331 /* set caps on pad if call succeeds */
2332 res = gst_pad_set_caps (pad, caps);
2333 /* no need to unref the caps here, set_caps takes a ref and
2334 * our ref goes away when we leave this function. */
2340 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2341 "caps %" GST_PTR_FORMAT " not accepted", caps);
2346 /* returns TRUE if the src pad could be configured to accept the given caps */
2348 gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
2350 GstPadSetCapsFunction setcaps;
2353 setcaps = GST_PAD_SETCAPSFUNC (pad);
2355 /* See if pad accepts the caps - only needed if
2356 * no setcaps function */
2357 if (setcaps == NULL)
2358 if (!gst_pad_accept_caps (pad, caps))
2362 res = gst_pad_set_caps (pad, caps);
2370 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2371 "caps %" GST_PTR_FORMAT " not accepted", caps);
2377 * gst_pad_get_pad_template_caps:
2378 * @pad: a #GstPad to get the template capabilities from.
2380 * Gets the capabilities for @pad's template.
2382 * Returns: the #GstCaps of this pad template. If you intend to keep a reference
2383 * on the caps, make a copy (see gst_caps_copy ()).
2386 gst_pad_get_pad_template_caps (GstPad * pad)
2388 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2390 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2392 if (GST_PAD_PAD_TEMPLATE (pad))
2393 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2395 return gst_static_caps_get (&anycaps);
2401 * @pad: a #GstPad to get the peer of.
2403 * Gets the peer of @pad. This function refs the peer pad so
2404 * you need to unref it after use.
2406 * Returns: the peer #GstPad. Unref after usage.
2411 gst_pad_get_peer (GstPad * pad)
2415 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2417 GST_OBJECT_LOCK (pad);
2418 result = GST_PAD_PEER (pad);
2420 gst_object_ref (result);
2421 GST_OBJECT_UNLOCK (pad);
2427 * gst_pad_get_allowed_caps:
2428 * @srcpad: a #GstPad, it must a a source pad.
2430 * Gets the capabilities of the allowed media types that can flow through
2431 * @srcpad and its peer. The pad must be a source pad.
2432 * The caller must free the resulting caps.
2434 * Returns: the allowed #GstCaps of the pad link. Free the caps when
2435 * you no longer need it. This function returns NULL when the @srcpad has no
2441 gst_pad_get_allowed_caps (GstPad * srcpad)
2448 g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
2449 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
2451 GST_OBJECT_LOCK (srcpad);
2453 peer = GST_PAD_PEER (srcpad);
2454 if (G_UNLIKELY (peer == NULL))
2457 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "getting allowed caps");
2459 gst_object_ref (peer);
2460 GST_OBJECT_UNLOCK (srcpad);
2461 mycaps = gst_pad_get_caps (srcpad);
2463 peercaps = gst_pad_get_caps (peer);
2464 gst_object_unref (peer);
2466 caps = gst_caps_intersect (mycaps, peercaps);
2467 gst_caps_unref (peercaps);
2468 gst_caps_unref (mycaps);
2470 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, srcpad, "allowed caps %" GST_PTR_FORMAT,
2477 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "no peer");
2478 GST_OBJECT_UNLOCK (srcpad);
2485 * gst_pad_get_negotiated_caps:
2488 * Gets the capabilities of the media type that currently flows through @pad
2491 * This function can be used on both src and sinkpads. Note that srcpads are
2492 * always negotiated before sinkpads so it is possible that the negotiated caps
2493 * on the srcpad do not match the negotiated caps of the peer.
2495 * Returns: the negotiated #GstCaps of the pad link. Free the caps when
2496 * you no longer need it. This function returns NULL when the @pad has no
2497 * peer or is not negotiated yet.
2502 gst_pad_get_negotiated_caps (GstPad * pad)
2507 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2509 GST_OBJECT_LOCK (pad);
2511 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2514 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
2516 caps = GST_PAD_CAPS (pad);
2518 gst_caps_ref (caps);
2519 GST_OBJECT_UNLOCK (pad);
2521 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
2528 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2529 GST_OBJECT_UNLOCK (pad);
2535 /* calls the buffer_alloc function on the given pad */
2536 static GstFlowReturn
2537 gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
2538 GstCaps * caps, GstBuffer ** buf)
2541 GstPadBufferAllocFunction bufferallocfunc;
2543 GST_OBJECT_LOCK (pad);
2544 /* when the pad is flushing we cannot give a buffer */
2545 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2548 if (offset == GST_BUFFER_OFFSET_NONE) {
2549 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2550 "calling bufferallocfunc &%s (@%p) for size %d offset NONE",
2551 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), &bufferallocfunc, size);
2553 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2554 "calling bufferallocfunc &%s (@%p) of for size %d offset %"
2555 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2556 &bufferallocfunc, size, offset);
2558 GST_OBJECT_UNLOCK (pad);
2560 /* G_LIKELY for now since most elements don't implement a buffer alloc
2561 * function and there is no default alloc proxy function as this is usually
2563 if (G_LIKELY ((bufferallocfunc = pad->bufferallocfunc) == NULL))
2566 ret = bufferallocfunc (pad, offset, size, caps, buf);
2567 if (G_UNLIKELY (ret != GST_FLOW_OK))
2569 /* no error, but NULL buffer means fallback to the default */
2570 if (G_UNLIKELY (*buf == NULL))
2573 /* If the buffer alloc function didn't set up the caps like it should,
2575 if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
2576 GST_WARNING_OBJECT (pad,
2577 "Buffer allocation function did not set caps. Setting");
2578 gst_buffer_set_caps (*buf, caps);
2584 /* pad was flushing */
2585 GST_OBJECT_UNLOCK (pad);
2586 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
2587 return GST_FLOW_WRONG_STATE;
2591 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2592 "alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
2597 /* fallback case, allocate a buffer of our own, add pad caps. */
2598 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
2600 *buf = gst_buffer_new_and_alloc (size);
2601 GST_BUFFER_OFFSET (*buf) = offset;
2602 gst_buffer_set_caps (*buf, caps);
2608 static GstFlowReturn
2609 gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
2610 GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
2614 gboolean caps_changed;
2616 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2617 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2618 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2620 GST_OBJECT_LOCK (pad);
2621 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2622 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
2625 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2628 gst_object_ref (peer);
2629 GST_OBJECT_UNLOCK (pad);
2631 ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
2632 gst_object_unref (peer);
2634 if (G_UNLIKELY (ret != GST_FLOW_OK))
2637 /* FIXME, move capnego this into a base class? */
2638 caps = GST_BUFFER_CAPS (*buf);
2640 /* Lock for checking caps, pretty pointless as the _pad_push() function might
2641 * change it concurrently, one of the problems with automatic caps setting in
2642 * pad_alloc_and_set_caps. Worst case, if does a check too much, but only when
2643 * there is heavy renegotiation going on in both directions. */
2644 GST_OBJECT_LOCK (pad);
2645 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2646 GST_OBJECT_UNLOCK (pad);
2648 /* we got a new datatype on the pad, see if it can handle it */
2649 if (G_UNLIKELY (caps_changed)) {
2650 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
2651 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, setcaps)))
2652 goto not_negotiated;
2658 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
2659 GST_OBJECT_UNLOCK (pad);
2664 /* pad has no peer */
2665 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2666 "called bufferallocfunc but had no peer");
2667 GST_OBJECT_UNLOCK (pad);
2668 return GST_FLOW_NOT_LINKED;
2672 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2673 "alloc function returned error %s", gst_flow_get_name (ret));
2678 gst_buffer_unref (*buf);
2680 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2681 "alloc function returned unacceptable buffer");
2682 return GST_FLOW_NOT_NEGOTIATED;
2687 * gst_pad_alloc_buffer:
2688 * @pad: a source #GstPad
2689 * @offset: the offset of the new buffer in the stream
2690 * @size: the size of the new buffer
2691 * @caps: the caps of the new buffer
2692 * @buf: a newly allocated buffer
2694 * Allocates a new, empty buffer optimized to push to pad @pad. This
2695 * function only works if @pad is a source pad and has a peer.
2697 * A new, empty #GstBuffer will be put in the @buf argument.
2698 * You need to check the caps of the buffer after performing this
2699 * function and renegotiate to the format if needed.
2701 * Returns: a result code indicating success of the operation. Any
2702 * result code other than #GST_FLOW_OK is an error and @buf should
2704 * An error can occur if the pad is not connected or when the downstream
2705 * peer elements cannot provide an acceptable buffer.
2710 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
2713 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
2717 * gst_pad_alloc_buffer_and_set_caps:
2718 * @pad: a source #GstPad
2719 * @offset: the offset of the new buffer in the stream
2720 * @size: the size of the new buffer
2721 * @caps: the caps of the new buffer
2722 * @buf: a newly allocated buffer
2724 * In addition to the function gst_pad_alloc_buffer(), this function
2725 * automatically calls gst_pad_set_caps() when the caps of the
2726 * newly allocated buffer are different from the @pad caps.
2728 * Returns: a result code indicating success of the operation. Any
2729 * result code other than #GST_FLOW_OK is an error and @buf should
2731 * An error can occur if the pad is not connected or when the downstream
2732 * peer elements cannot provide an acceptable buffer.
2737 gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
2738 GstCaps * caps, GstBuffer ** buf)
2740 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
2744 * gst_pad_get_internal_links_default:
2745 * @pad: the #GstPad to get the internal links of.
2747 * Gets a list of pads to which the given pad is linked to
2748 * inside of the parent element.
2749 * This is the default handler, and thus returns a list of all of the
2750 * pads inside the parent element with opposite direction.
2751 * The caller must free this list after use.
2753 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
2758 gst_pad_get_internal_links_default (GstPad * pad)
2763 GstPadDirection direction;
2765 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2767 direction = pad->direction;
2769 parent = GST_PAD_PARENT (pad);
2773 parent_pads = parent->pads;
2775 while (parent_pads) {
2776 GstPad *parent_pad = GST_PAD_CAST (parent_pads->data);
2778 if (parent_pad->direction != direction) {
2779 res = g_list_prepend (res, parent_pad);
2782 parent_pads = g_list_next (parent_pads);
2789 * gst_pad_get_internal_links:
2790 * @pad: the #GstPad to get the internal links of.
2792 * Gets a list of pads to which the given pad is linked to
2793 * inside of the parent element.
2794 * The caller must free this list after use.
2796 * Returns: a newly allocated #GList of pads.
2801 gst_pad_get_internal_links (GstPad * pad)
2805 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2807 if (GST_PAD_INTLINKFUNC (pad))
2808 res = GST_PAD_INTLINKFUNC (pad) (pad);
2815 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
2820 GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
2823 result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
2825 orig = pads = gst_pad_get_internal_links (pad);
2828 GstPad *eventpad = GST_PAD_CAST (pads->data);
2830 pads = g_list_next (pads);
2832 if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
2833 /* for each pad we send to, we should ref the event; it's up
2834 * to downstream to unref again when handled. */
2835 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
2836 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2837 gst_event_ref (event);
2838 gst_pad_push_event (eventpad, event);
2840 /* we only send the event on one pad, multi-sinkpad elements
2841 * should implement a handler */
2842 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
2843 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2844 result = gst_pad_push_event (eventpad, event);
2848 /* we handled the incoming event so we unref once */
2849 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
2850 gst_event_unref (event);
2859 * gst_pad_event_default:
2860 * @pad: a #GstPad to call the default event handler on.
2861 * @event: the #GstEvent to handle.
2863 * Invokes the default event handler for the given pad. End-of-stream and
2864 * discontinuity events are handled specially, and then the event is sent to all
2865 * pads internally linked to @pad. Note that if there are many possible sink
2866 * pads that are internally linked to @pad, only one will be sent an event.
2867 * Multi-sinkpad elements should implement custom event handlers.
2869 * Returns: TRUE if the event was sent succesfully.
2872 gst_pad_event_default (GstPad * pad, GstEvent * event)
2874 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2875 g_return_val_if_fail (event != NULL, FALSE);
2877 switch (GST_EVENT_TYPE (event)) {
2880 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
2881 gst_pad_pause_task (pad);
2887 return gst_pad_event_default_dispatch (pad, event);
2891 * gst_pad_dispatcher:
2892 * @pad: a #GstPad to dispatch.
2893 * @dispatch: the #GstDispatcherFunction to call.
2894 * @data: gpointer user data passed to the dispatcher function.
2896 * Invokes the given dispatcher function on all pads that are
2897 * internally linked to the given pad.
2898 * The GstPadDispatcherFunction should return TRUE when no further pads
2899 * need to be processed.
2901 * Returns: TRUE if one of the dispatcher functions returned TRUE.
2904 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
2907 gboolean res = FALSE;
2908 GList *int_pads, *orig;
2910 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2911 g_return_val_if_fail (dispatch != NULL, FALSE);
2913 orig = int_pads = gst_pad_get_internal_links (pad);
2916 GstPad *int_pad = GST_PAD_CAST (int_pads->data);
2917 GstPad *int_peer = GST_PAD_PEER (int_pad);
2920 res = dispatch (int_peer, data);
2924 int_pads = g_list_next (int_pads);
2934 * @pad: a #GstPad to invoke the default query on.
2935 * @query: the #GstQuery to perform.
2937 * Dispatches a query to a pad. The query should have been allocated by the
2938 * caller via one of the type-specific allocation functions in gstquery.h. The
2939 * element is responsible for filling the query with an appropriate response,
2940 * which should then be parsed with a type-specific query parsing function.
2942 * Again, the caller is responsible for both the allocation and deallocation of
2943 * the query structure.
2945 * Returns: TRUE if the query could be performed.
2948 gst_pad_query (GstPad * pad, GstQuery * query)
2950 GstPadQueryFunction func;
2952 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2953 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2955 GST_DEBUG_OBJECT (pad, "sending query %p", query);
2957 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
2960 return func (pad, query);
2964 GST_DEBUG_OBJECT (pad, "had no query function");
2970 * gst_pad_query_default:
2971 * @pad: a #GstPad to call the default query handler on.
2972 * @query: the #GstQuery to handle.
2974 * Invokes the default query handler for the given pad.
2975 * The query is sent to all pads internally linked to @pad. Note that
2976 * if there are many possible sink pads that are internally linked to
2977 * @pad, only one will be sent the query.
2978 * Multi-sinkpad elements should implement custom query handlers.
2980 * Returns: TRUE if the query was performed succesfully.
2983 gst_pad_query_default (GstPad * pad, GstQuery * query)
2985 switch (GST_QUERY_TYPE (query)) {
2986 case GST_QUERY_POSITION:
2987 case GST_QUERY_SEEKING:
2988 case GST_QUERY_FORMATS:
2989 case GST_QUERY_LATENCY:
2990 case GST_QUERY_JITTER:
2991 case GST_QUERY_RATE:
2992 case GST_QUERY_CONVERT:
2994 return gst_pad_dispatcher
2995 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
2999 #ifndef GST_DISABLE_LOADSAVE
3000 /* FIXME: why isn't this on a GstElement ? */
3002 * gst_pad_load_and_link:
3003 * @self: an #xmlNodePtr to read the description from.
3004 * @parent: the #GstObject element that owns the pad.
3006 * Reads the pad definition from the XML node and links the given pad
3007 * in the element to a pad of an element up in the hierarchy.
3010 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
3012 xmlNodePtr field = self->xmlChildrenNode;
3013 GstPad *pad = NULL, *targetpad;
3017 GstObject *grandparent;
3021 if (!strcmp ((char *) field->name, "name")) {
3022 name = (gchar *) xmlNodeGetContent (field);
3023 pad = gst_element_get_pad (GST_ELEMENT (parent), name);
3025 } else if (!strcmp ((char *) field->name, "peer")) {
3026 peer = (gchar *) xmlNodeGetContent (field);
3028 field = field->next;
3030 g_return_if_fail (pad != NULL);
3035 split = g_strsplit (peer, ".", 2);
3037 if (split[0] == NULL || split[1] == NULL) {
3038 GST_CAT_DEBUG_OBJECT (GST_CAT_XML, pad,
3039 "Could not parse peer '%s', leaving unlinked", peer);
3046 g_return_if_fail (split[0] != NULL);
3047 g_return_if_fail (split[1] != NULL);
3049 grandparent = gst_object_get_parent (parent);
3051 if (grandparent && GST_IS_BIN (grandparent)) {
3052 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
3059 targetpad = gst_element_get_pad (target, split[1]);
3061 if (targetpad == NULL)
3064 gst_pad_link (pad, targetpad);
3071 * gst_pad_save_thyself:
3072 * @pad: a #GstPad to save.
3073 * @parent: the parent #xmlNodePtr to save the description in.
3075 * Saves the pad into an xml representation.
3077 * Returns: the #xmlNodePtr representation of the pad.
3080 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
3085 g_return_val_if_fail (GST_IS_PAD (object), NULL);
3087 pad = GST_PAD (object);
3089 xmlNewChild (parent, NULL, (xmlChar *) "name",
3090 (xmlChar *) GST_PAD_NAME (pad));
3091 if (GST_PAD_PEER (pad) != NULL) {
3094 peer = GST_PAD_PEER (pad);
3095 /* first check to see if the peer's parent's parent is the same */
3096 /* we just save it off */
3097 content = g_strdup_printf ("%s.%s",
3098 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
3099 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
3102 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
3109 * gst_ghost_pad_save_thyself:
3110 * @pad: a ghost #GstPad to save.
3111 * @parent: the parent #xmlNodePtr to save the description in.
3113 * Saves the ghost pad into an xml representation.
3115 * Returns: the #xmlNodePtr representation of the pad.
3118 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
3122 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
3124 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
3125 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
3126 xmlNewChild (self, NULL, (xmlChar *) "parent",
3127 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
3129 /* FIXME FIXME FIXME! */
3134 #endif /* GST_DISABLE_LOADSAVE */
3137 * should be called with pad OBJECT_LOCK and STREAM_LOCK held.
3138 * GST_PAD_IS_BLOCK (pad) == TRUE when this function is
3141 * This function perform the pad blocking when an event, buffer push
3142 * or buffer_alloc is performed on a _SRC_ pad. It blocks the
3143 * streaming thread after informing the pad has been blocked.
3145 * An application can with this method wait and block any streaming
3146 * thread and perform operations such as seeking or linking.
3148 * Two methods are available for notifying the application of the
3150 * - the callback method, which happens in the STREAMING thread with
3151 * the STREAM_LOCK held. With this method, the most usefull way of
3152 * dealing with the callback is to post a message to the main thread
3153 * where the pad block can then be handled outside of the streaming
3154 * thread. With the last method one can perform all operations such
3155 * as doing a state change, linking, unblocking, seeking etc on the
3157 * - the GCond signal method, which makes any thread unblock when
3158 * the pad block happens.
3162 static GstFlowReturn
3163 handle_pad_block (GstPad * pad)
3165 GstPadBlockCallback callback;
3167 GstFlowReturn ret = GST_FLOW_OK;
3169 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
3171 /* flushing, don't bother trying to block and return WRONG_STATE
3173 if (GST_PAD_IS_FLUSHING (pad))
3174 goto flushingnonref;
3176 /* we grab an extra ref for the callbacks, this is probably not
3177 * needed (callback code does not have a ref and cannot unref). I
3178 * think this was done to make it possible to unref the element in
3179 * the callback, which is in the end totally impossible as it
3180 * requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
3181 * all taken when calling this function. */
3182 gst_object_ref (pad);
3184 /* we either have a callback installed to notify the block or
3185 * some other thread is doing a GCond wait. */
3186 callback = pad->block_callback;
3188 /* there is a callback installed, call it. We release the
3189 * lock so that the callback can do something usefull with the
3191 user_data = pad->block_data;
3192 GST_OBJECT_UNLOCK (pad);
3193 callback (pad, TRUE, user_data);
3194 GST_OBJECT_LOCK (pad);
3196 /* no callback, signal the thread that is doing a GCond wait
3198 GST_PAD_BLOCK_SIGNAL (pad);
3201 /* OBJECT_LOCK could have been released when we did the callback, which
3202 * then could have made the pad unblock so we need to check the blocking
3203 * condition again. */
3204 while (GST_PAD_IS_BLOCKED (pad)) {
3205 if (GST_PAD_IS_FLUSHING (pad))
3208 /* now we block the streaming thread. It can be unlocked when we
3209 * deactivate the pad (which will also set the FLUSHING flag) or
3210 * when the pad is unblocked. A flushing event will also unblock
3211 * the pad after setting the FLUSHING flag. */
3212 GST_PAD_BLOCK_WAIT (pad);
3214 /* see if we got unlocked by a flush or not */
3215 if (GST_PAD_IS_FLUSHING (pad))
3219 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
3221 /* when we get here, the pad is unblocked again and we perform
3222 * the needed unblock code. */
3223 callback = pad->block_callback;
3225 /* we need to call the callback */
3226 user_data = pad->block_data;
3227 GST_OBJECT_UNLOCK (pad);
3228 callback (pad, FALSE, user_data);
3229 GST_OBJECT_LOCK (pad);
3231 /* we need to signal the thread waiting on the GCond */
3232 GST_PAD_BLOCK_SIGNAL (pad);
3235 gst_object_unref (pad);
3241 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
3242 return GST_FLOW_WRONG_STATE;
3246 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
3247 gst_object_unref (pad);
3248 return GST_FLOW_WRONG_STATE;
3252 /**********************************************************************
3253 * Data passing functions
3257 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
3260 GValue args[2] = { {0}, {0} };
3265 g_value_init (&ret, G_TYPE_BOOLEAN);
3266 g_value_set_boolean (&ret, TRUE);
3267 g_value_init (&args[0], GST_TYPE_PAD);
3268 g_value_set_object (&args[0], pad);
3269 g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
3270 gst_value_set_mini_object (&args[1], obj);
3272 if (GST_IS_EVENT (obj))
3273 detail = event_quark;
3275 detail = buffer_quark;
3278 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
3279 res = g_value_get_boolean (&ret);
3282 g_value_unset (&ret);
3283 g_value_unset (&args[0]);
3284 g_value_unset (&args[1]);
3289 /* this is the chain function that does not perform the additional argument
3290 * checking for that little extra speed.
3292 static inline GstFlowReturn
3293 gst_pad_chain_unchecked (GstPad * pad, GstBuffer * buffer)
3296 gboolean caps_changed;
3297 GstPadChainFunction chainfunc;
3299 gboolean emit_signal;
3301 GST_PAD_STREAM_LOCK (pad);
3303 GST_OBJECT_LOCK (pad);
3304 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3307 caps = GST_BUFFER_CAPS (buffer);
3308 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3310 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3311 GST_OBJECT_UNLOCK (pad);
3313 /* see if the signal should be emited, we emit before caps nego as
3314 * we might drop the buffer and do capsnego for nothing. */
3315 if (G_UNLIKELY (emit_signal)) {
3316 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3320 /* we got a new datatype on the pad, see if it can handle it */
3321 if (G_UNLIKELY (caps_changed)) {
3322 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3323 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
3324 goto not_negotiated;
3327 /* NOTE: we read the chainfunc unlocked.
3328 * we cannot hold the lock for the pad so we might send
3329 * the data to the wrong function. This is not really a
3330 * problem since functions are assigned at creation time
3331 * and don't change that often... */
3332 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
3335 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3336 "calling chainfunction &%s", GST_DEBUG_FUNCPTR_NAME (chainfunc));
3338 ret = chainfunc (pad, buffer);
3340 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3341 "called chainfunction &%s, returned %s",
3342 GST_DEBUG_FUNCPTR_NAME (chainfunc), gst_flow_get_name (ret));
3344 GST_PAD_STREAM_UNLOCK (pad);
3351 gst_buffer_unref (buffer);
3352 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3353 "pushing, but pad was flushing");
3354 GST_OBJECT_UNLOCK (pad);
3355 GST_PAD_STREAM_UNLOCK (pad);
3356 return GST_FLOW_WRONG_STATE;
3360 gst_buffer_unref (buffer);
3361 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3362 GST_PAD_STREAM_UNLOCK (pad);
3367 gst_buffer_unref (buffer);
3368 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3369 "pushing buffer but pad did not accept");
3370 GST_PAD_STREAM_UNLOCK (pad);
3371 return GST_FLOW_NOT_NEGOTIATED;
3375 gst_buffer_unref (buffer);
3376 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3377 "pushing, but not chainhandler");
3378 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3379 ("push on pad %s:%s but it has no chainfunction",
3380 GST_DEBUG_PAD_NAME (pad)));
3381 GST_PAD_STREAM_UNLOCK (pad);
3382 return GST_FLOW_NOT_SUPPORTED;
3388 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3389 * @buffer: the #GstBuffer to send, return GST_FLOW_ERROR if not.
3391 * Chain a buffer to @pad.
3393 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
3395 * If the caps on @buffer are different from the current caps on @pad, this
3396 * function will call any setcaps function (see gst_pad_set_setcaps_function())
3397 * installed on @pad. If the new caps are not acceptable for @pad, this function
3398 * returns #GST_FLOW_NOT_NEGOTIATED.
3400 * The function proceeds calling the chain function installed on @pad (see
3401 * gst_pad_set_chain_function()) and the return value of that function is
3402 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
3405 * In all cases, success or failure, the caller loses its reference to @buffer
3406 * after calling this function.
3408 * Returns: a #GstFlowReturn from the pad.
3413 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
3415 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3416 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3418 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3420 return gst_pad_chain_unchecked (pad, buffer);
3425 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
3426 * @buffer: the #GstBuffer to push returns GST_FLOW_ERROR if not.
3428 * Pushes a buffer to the peer of @pad.
3430 * This function will call an installed pad block before triggering any
3431 * installed pad probes.
3433 * If the caps on @buffer are different from the currently configured caps on
3434 * @pad, this function will call any installed setcaps function on @pad (see
3435 * gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
3436 * format, this function returns #GST_FLOW_NOT_NEGOTIATED.
3438 * The function proceeds calling gst_pad_chain() on the peer pad and returns the
3439 * value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will be
3442 * In all cases, success or failure, the caller loses its reference to @buffer
3443 * after calling this function.
3445 * Returns: a #GstFlowReturn from the peer pad.
3450 gst_pad_push (GstPad * pad, GstBuffer * buffer)
3456 gboolean caps_changed;
3458 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3459 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3460 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3462 GST_OBJECT_LOCK (pad);
3464 /* FIXME: this check can go away; pad_set_blocked could be implemented with
3465 * probes completely or probes with an extended pad block. */
3466 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3467 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
3470 /* we emit signals on the pad arg, the peer will have a chance to
3471 * emit in the _chain() function */
3472 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
3473 /* unlock before emitting */
3474 GST_OBJECT_UNLOCK (pad);
3476 /* if the signal handler returned FALSE, it means we should just drop the
3478 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3481 GST_OBJECT_LOCK (pad);
3484 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3487 /* take ref to peer pad before releasing the lock */
3488 gst_object_ref (peer);
3490 /* Before pushing the buffer to the peer pad, ensure that caps
3491 * are set on this pad */
3492 caps = GST_BUFFER_CAPS (buffer);
3493 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3495 GST_OBJECT_UNLOCK (pad);
3497 /* we got a new datatype from the pad, it had better handle it */
3498 if (G_UNLIKELY (caps_changed)) {
3499 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3500 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
3501 goto not_negotiated;
3504 ret = gst_pad_chain_unchecked (peer, buffer);
3506 gst_object_unref (peer);
3510 /* ERROR recovery here */
3513 gst_buffer_unref (buffer);
3514 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
3515 GST_OBJECT_UNLOCK (pad);
3520 gst_buffer_unref (buffer);
3521 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3526 gst_buffer_unref (buffer);
3527 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3528 "pushing, but it was not linked");
3529 GST_OBJECT_UNLOCK (pad);
3530 return GST_FLOW_NOT_LINKED;
3534 gst_buffer_unref (buffer);
3535 gst_object_unref (peer);
3536 GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
3537 "element pushed buffer then refused to accept the caps");
3538 return GST_FLOW_NOT_NEGOTIATED;
3543 * gst_pad_check_pull_range:
3544 * @pad: a sink #GstPad.
3546 * Checks if a gst_pad_pull_range() can be performed on the peer
3547 * source pad. This function is used by plugins that want to check
3548 * if they can use random access on the peer source pad.
3550 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
3551 * if it needs to perform some logic to determine if pull_range is
3554 * Returns: a gboolean with the result.
3559 gst_pad_check_pull_range (GstPad * pad)
3563 GstPadCheckGetRangeFunction checkgetrangefunc;
3565 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3567 GST_OBJECT_LOCK (pad);
3568 if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
3569 goto wrong_direction;
3571 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3574 gst_object_ref (peer);
3575 GST_OBJECT_UNLOCK (pad);
3577 /* see note in above function */
3578 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
3579 /* FIXME, kindoff ghetto */
3580 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
3582 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3583 "calling checkgetrangefunc %s of peer pad %s:%s",
3584 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
3586 ret = checkgetrangefunc (peer);
3589 gst_object_unref (peer);
3593 /* ERROR recovery here */
3596 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3597 "checking pull range, but pad must be a sinkpad");
3598 GST_OBJECT_UNLOCK (pad);
3603 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3604 "checking pull range, but it was not linked");
3605 GST_OBJECT_UNLOCK (pad);
3611 * gst_pad_get_range:
3612 * @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
3613 * @offset: The start offset of the buffer
3614 * @size: The length of the buffer
3615 * @buffer: a pointer to hold the #GstBuffer, returns #GST_FLOW_ERROR if %NULL.
3617 * When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
3620 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
3621 * description of a getrange function. If @pad has no getrange function
3622 * installed (see gst_pad_set_getrange_function()) this function returns
3623 * #GST_FLOW_NOT_SUPPORTED.
3625 * Returns: a #GstFlowReturn from the pad.
3630 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
3631 GstBuffer ** buffer)
3634 GstPadGetRangeFunction getrangefunc;
3635 gboolean emit_signal;
3637 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3638 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3639 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3641 GST_PAD_STREAM_LOCK (pad);
3643 GST_OBJECT_LOCK (pad);
3644 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3647 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3648 GST_OBJECT_UNLOCK (pad);
3650 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
3653 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3654 "calling getrangefunc %s, offset %"
3655 G_GUINT64_FORMAT ", size %u",
3656 GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
3658 ret = getrangefunc (pad, offset, size, buffer);
3660 /* can only fire the signal if we have a valid buffer */
3661 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3662 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3666 GST_PAD_STREAM_UNLOCK (pad);
3673 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3674 "pulling range, but pad was flushing");
3675 GST_OBJECT_UNLOCK (pad);
3676 GST_PAD_STREAM_UNLOCK (pad);
3677 return GST_FLOW_WRONG_STATE;
3681 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3682 ("pullrange on pad %s:%s but it has no getrangefunction",
3683 GST_DEBUG_PAD_NAME (pad)));
3684 GST_PAD_STREAM_UNLOCK (pad);
3685 return GST_FLOW_NOT_SUPPORTED;
3689 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3690 "Dropping data after FALSE probe return");
3691 GST_PAD_STREAM_UNLOCK (pad);
3692 gst_buffer_unref (*buffer);
3694 return GST_FLOW_UNEXPECTED;
3700 * gst_pad_pull_range:
3701 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3702 * @offset: The start offset of the buffer
3703 * @size: The length of the buffer
3704 * @buffer: a pointer to hold the #GstBuffer, returns GST_FLOW_ERROR if %NULL.
3706 * Pulls a buffer from the peer pad.
3708 * This function will first trigger the pad block signal if it was
3711 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
3712 * function returns the result of gst_pad_get_range() on the peer pad.
3713 * See gst_pad_get_range() for a list of return values and for the
3714 * semantics of the arguments of this function.
3716 * Returns: a #GstFlowReturn from the peer pad.
3717 * When this function returns #GST_FLOW_OK, @buffer will contain a valid
3718 * #GstBuffer that should be freed with gst_buffer_unref() after usage.
3719 * @buffer may not be used or freed when any other return value than
3720 * #GST_FLOW_OK is returned.
3725 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
3726 GstBuffer ** buffer)
3730 gboolean emit_signal;
3732 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3733 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3735 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3737 GST_OBJECT_LOCK (pad);
3739 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3740 handle_pad_block (pad);
3742 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3745 /* signal emision for the pad, peer has chance to emit when
3746 * we call _get_range() */
3747 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3749 gst_object_ref (peer);
3750 GST_OBJECT_UNLOCK (pad);
3752 ret = gst_pad_get_range (peer, offset, size, buffer);
3754 gst_object_unref (peer);
3756 /* can only fire the signal if we have a valid buffer */
3757 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3758 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3763 /* ERROR recovery here */
3766 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3767 "pulling range, but it was not linked");
3768 GST_OBJECT_UNLOCK (pad);
3769 return GST_FLOW_NOT_LINKED;
3773 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3774 "Dropping data after FALSE probe return");
3775 gst_buffer_unref (*buffer);
3777 return GST_FLOW_UNEXPECTED;
3782 * gst_pad_push_event:
3783 * @pad: a #GstPad to push the event to.
3784 * @event: the #GstEvent to send to the pad.
3786 * Sends the event to the peer of the given pad. This function is
3787 * mainly used by elements to send events to their peer
3790 * This function takes owership of the provided event so you should
3791 * gst_event_ref() it if you want to reuse the event after this call.
3793 * Returns: TRUE if the event was handled.
3798 gst_pad_push_event (GstPad * pad, GstEvent * event)
3803 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3804 g_return_val_if_fail (event != NULL, FALSE);
3805 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
3807 GST_LOG_OBJECT (pad, "event:%s", GST_EVENT_TYPE_NAME (event));
3809 GST_OBJECT_LOCK (pad);
3811 /* Two checks to be made:
3812 * . (un)set the FLUSHING flag for flushing events,
3813 * . handle pad blocking */
3814 switch (GST_EVENT_TYPE (event)) {
3815 case GST_EVENT_FLUSH_START:
3816 GST_PAD_SET_FLUSHING (pad);
3818 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3819 /* flush start will have set the FLUSHING flag and will then
3820 * unlock all threads doing a GCond wait on the blocked pad. This
3821 * will typically unblock the STREAMING thread blocked on a pad. */
3822 GST_PAD_BLOCK_SIGNAL (pad);
3826 case GST_EVENT_FLUSH_STOP:
3827 GST_PAD_UNSET_FLUSHING (pad);
3829 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3833 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3834 if (GST_PAD_IS_FLUSHING (pad))
3836 while (GST_PAD_IS_BLOCKED (pad))
3837 /* else block the event as long as the pad is blocked */
3838 if (handle_pad_block (pad) != GST_FLOW_OK)
3844 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3845 GST_OBJECT_UNLOCK (pad);
3847 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3850 GST_OBJECT_LOCK (pad);
3852 peerpad = GST_PAD_PEER (pad);
3853 if (peerpad == NULL)
3856 GST_LOG_OBJECT (peerpad, "sending event on peerpad");
3857 gst_object_ref (peerpad);
3858 GST_OBJECT_UNLOCK (pad);
3860 result = gst_pad_send_event (peerpad, event);
3862 gst_object_unref (peerpad);
3863 GST_LOG_OBJECT (peerpad, "sent event on peerpad");
3867 /* ERROR handling */
3870 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
3871 gst_event_unref (event);
3876 GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
3877 gst_event_unref (event);
3878 GST_OBJECT_UNLOCK (pad);
3884 GST_DEBUG_OBJECT (pad,
3885 "Not forwarding event since we're flushing and blocking");
3886 gst_event_unref (event);
3887 GST_OBJECT_UNLOCK (pad);
3893 * gst_pad_send_event:
3894 * @pad: a #GstPad to send the event to.
3895 * @event: the #GstEvent to send to the pad.
3897 * Sends the event to the pad. This function can be used
3898 * by applications to send events in the pipeline.
3900 * If @pad is a source pad, @event should be an upstream event. If @pad is a
3901 * sink pad, @event should be a downstream event. For example, you would not
3902 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
3903 * Furthermore, some downstream events have to be serialized with data flow,
3904 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
3905 * the event needs to be serialized with data flow, this function will take the
3906 * pad's stream lock while calling its event function.
3908 * To find out whether an event type is upstream, downstream, or downstream and
3909 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
3910 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
3911 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or plugin
3912 * doesn't need to bother itself with this information; the core handles all
3913 * necessary locks and checks.
3915 * This function takes owership of the provided event so you should
3916 * gst_event_ref() it if you want to reuse the event after this call.
3918 * Returns: TRUE if the event was handled.
3921 gst_pad_send_event (GstPad * pad, GstEvent * event)
3923 gboolean result = FALSE;
3924 GstPadEventFunction eventfunc;
3925 gboolean serialized, need_unlock = FALSE;
3927 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3928 g_return_val_if_fail (event != NULL, FALSE);
3930 GST_OBJECT_LOCK (pad);
3931 if (GST_PAD_IS_SINK (pad)) {
3932 if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
3933 goto wrong_direction;
3934 serialized = GST_EVENT_IS_SERIALIZED (event);
3935 } else if (GST_PAD_IS_SRC (pad)) {
3936 if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
3937 goto wrong_direction;
3938 /* events on srcpad never are serialized */
3941 goto unknown_direction;
3943 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
3944 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
3945 GST_EVENT_SRC (event) = gst_object_ref (pad);
3949 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3950 GST_OBJECT_UNLOCK (pad);
3952 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
3955 GST_OBJECT_LOCK (pad);
3958 switch (GST_EVENT_TYPE (event)) {
3959 case GST_EVENT_FLUSH_START:
3960 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
3961 "have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
3963 /* can't even accept a flush begin event when flushing */
3964 if (GST_PAD_IS_FLUSHING (pad))
3966 GST_PAD_SET_FLUSHING (pad);
3967 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
3969 case GST_EVENT_FLUSH_STOP:
3970 GST_PAD_UNSET_FLUSHING (pad);
3971 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
3972 GST_OBJECT_UNLOCK (pad);
3973 /* grab stream lock */
3974 GST_PAD_STREAM_LOCK (pad);
3976 GST_OBJECT_LOCK (pad);
3979 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
3980 GST_EVENT_TYPE_NAME (event));
3982 /* make this a little faster, no point in grabbing the lock
3983 * if the pad is allready flushing. */
3984 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3988 /* lock order: STREAM_LOCK, LOCK */
3989 GST_OBJECT_UNLOCK (pad);
3990 GST_PAD_STREAM_LOCK (pad);
3992 GST_OBJECT_LOCK (pad);
3993 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3998 if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
4001 GST_OBJECT_UNLOCK (pad);
4003 result = eventfunc (pad, event);
4006 GST_PAD_STREAM_UNLOCK (pad);
4010 /* ERROR handling */
4013 g_warning ("pad %s:%s sending %s event in wrong direction",
4014 GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
4015 GST_OBJECT_UNLOCK (pad);
4016 gst_event_unref (event);
4021 g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
4022 GST_OBJECT_UNLOCK (pad);
4023 gst_event_unref (event);
4028 g_warning ("pad %s:%s has no event handler, file a bug.",
4029 GST_DEBUG_PAD_NAME (pad));
4030 GST_OBJECT_UNLOCK (pad);
4031 gst_event_unref (event);
4036 GST_OBJECT_UNLOCK (pad);
4038 GST_PAD_STREAM_UNLOCK (pad);
4039 GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
4040 "Received event on flushing pad. Discarding");
4041 gst_event_unref (event);
4046 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
4047 gst_event_unref (event);
4053 * gst_pad_set_element_private:
4054 * @pad: the #GstPad to set the private data of.
4055 * @priv: The private data to attach to the pad.
4057 * Set the given private data gpointer on the pad.
4058 * This function can only be used by the element that owns the pad.
4059 * No locking is performed in this function.
4062 gst_pad_set_element_private (GstPad * pad, gpointer priv)
4064 pad->element_private = priv;
4068 * gst_pad_get_element_private:
4069 * @pad: the #GstPad to get the private data of.
4071 * Gets the private data of a pad.
4072 * No locking is performed in this function.
4074 * Returns: a #gpointer to the private data.
4077 gst_pad_get_element_private (GstPad * pad)
4079 return pad->element_private;
4083 * gst_pad_start_task:
4084 * @pad: the #GstPad to start the task of
4085 * @func: the task function to call
4086 * @data: data passed to the task function
4088 * Starts a task that repeadedly calls @func with @data. This function
4089 * is nostly used in the pad activation function to start the
4090 * dataflow. This function will automatically acquire the STREAM_LOCK of
4091 * the pad before calling @func.
4093 * Returns: a TRUE if the task could be started.
4096 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
4100 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4101 g_return_val_if_fail (func != NULL, FALSE);
4103 GST_OBJECT_LOCK (pad);
4104 task = GST_PAD_TASK (pad);
4106 task = gst_task_create (func, data);
4107 gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
4108 GST_PAD_TASK (pad) = task;
4110 gst_task_start (task);
4111 GST_OBJECT_UNLOCK (pad);
4117 * gst_pad_pause_task:
4118 * @pad: the #GstPad to pause the task of
4120 * Pause the task of @pad. This function will also make sure that the
4121 * function executed by the task will effectively stop.
4123 * Returns: a TRUE if the task could be paused or FALSE when the pad
4127 gst_pad_pause_task (GstPad * pad)
4131 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4133 GST_OBJECT_LOCK (pad);
4134 task = GST_PAD_TASK (pad);
4137 gst_task_pause (task);
4138 GST_OBJECT_UNLOCK (pad);
4140 GST_PAD_STREAM_LOCK (pad);
4141 GST_PAD_STREAM_UNLOCK (pad);
4147 GST_DEBUG_OBJECT (pad, "pad has no task");
4148 GST_OBJECT_UNLOCK (pad);
4154 * gst_pad_stop_task:
4155 * @pad: the #GstPad to stop the task of
4157 * Stop the task of @pad. This function will also make sure that the
4158 * function executed by the task will effectively stop if not called
4159 * from the GstTaskFunction.
4161 * This function will deadlock if called from the GstTaskFunction of
4162 * the task. Use gst_task_pause() instead.
4164 * Regardless of whether the pad has a task, the stream lock is acquired and
4165 * released so as to ensure that streaming through this pad has finished.
4167 * Returns: a TRUE if the task could be stopped or FALSE on error.
4170 gst_pad_stop_task (GstPad * pad)
4174 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4176 GST_OBJECT_LOCK (pad);
4177 task = GST_PAD_TASK (pad);
4180 GST_PAD_TASK (pad) = NULL;
4181 gst_task_stop (task);
4182 GST_OBJECT_UNLOCK (pad);
4184 GST_PAD_STREAM_LOCK (pad);
4185 GST_PAD_STREAM_UNLOCK (pad);
4187 if (!gst_task_join (task))
4190 gst_object_unref (task);
4196 GST_OBJECT_UNLOCK (pad);
4198 GST_PAD_STREAM_LOCK (pad);
4199 GST_PAD_STREAM_UNLOCK (pad);
4201 /* this is not an error */
4206 /* this is bad, possibly the application tried to join the task from
4207 * the task's thread. We install the task again so that it will be stopped
4208 * again from the right thread next time hopefully. */
4209 GST_OBJECT_LOCK (pad);
4210 /* we can only install this task if there was no other task */
4211 if (GST_PAD_TASK (pad) == NULL)
4212 GST_PAD_TASK (pad) = task;
4213 GST_OBJECT_UNLOCK (pad);