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_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
787 active ? "activate" : "deactivate");
788 pre_activate (pad, GST_ACTIVATE_NONE);
789 post_activate (pad, GST_ACTIVATE_NONE);
795 * gst_pad_activate_push:
796 * @pad: the #GstPad to activate or deactivate.
797 * @active: whether the pad should be active or not.
799 * Activates or deactivates the given pad in push mode via dispatching to the
800 * pad's activatepushfunc. For use from within pad activation functions only.
802 * If you don't know what this is, you probably don't want to call it.
804 * Returns: %TRUE if the operation was successful.
809 gst_pad_activate_push (GstPad * pad, gboolean active)
811 GstActivateMode old, new;
813 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
814 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
815 active ? "activated" : "deactivated");
817 GST_OBJECT_LOCK (pad);
818 old = GST_PAD_ACTIVATE_MODE (pad);
819 GST_OBJECT_UNLOCK (pad);
823 case GST_ACTIVATE_PUSH:
825 case GST_ACTIVATE_PULL:
826 /* pad was activate in the wrong direction, deactivate it
827 * an reactivate it in push mode */
828 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
829 goto deactivate_failed;
830 /* fallthrough, pad is deactivated now. */
831 case GST_ACTIVATE_NONE:
836 case GST_ACTIVATE_NONE:
838 case GST_ACTIVATE_PULL:
839 /* pad was activated in the other direction, deactivate it
840 * in pull mode, this should not happen... */
841 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
842 goto deactivate_failed;
843 /* everything is fine now */
845 case GST_ACTIVATE_PUSH:
850 new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
851 pre_activate (pad, new);
853 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
854 if (G_UNLIKELY (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active))) {
858 /* quite ok, element relies on state change func to prepare itself */
861 post_activate (pad, new);
863 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
864 active ? "activated" : "deactivated");
869 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
870 active ? "activated" : "deactivated");
875 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
876 "failed to %s in switch to push from mode %d",
877 (active ? "activate" : "deactivate"), old);
882 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
883 active ? "activate" : "deactivate");
884 pre_activate (pad, GST_ACTIVATE_NONE);
885 post_activate (pad, GST_ACTIVATE_NONE);
892 * @pad: the #GstPad to query
894 * Query if a pad is active
896 * Returns: TRUE if the pad is active.
901 gst_pad_is_active (GstPad * pad)
903 gboolean result = FALSE;
905 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
907 GST_OBJECT_LOCK (pad);
908 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
909 GST_OBJECT_UNLOCK (pad);
915 * gst_pad_set_blocked_async:
916 * @pad: the #GstPad to block or unblock
917 * @blocked: boolean indicating whether the pad should be blocked or unblocked
918 * @callback: #GstPadBlockCallback that will be called when the
920 * @user_data: user data passed to the callback
922 * Blocks or unblocks the dataflow on a pad. The provided callback
923 * is called when the operation succeeds; this happens right before the next
924 * attempt at pushing a buffer on the pad.
926 * This can take a while as the pad can only become blocked when real dataflow
928 * When the pipeline is stalled, for example in PAUSED, this can
929 * take an indeterminate amount of time.
930 * You can pass NULL as the callback to make this call block. Be careful with
931 * this blocking call as it might not return for reasons stated above.
933 * Returns: TRUE if the pad could be blocked. This function can fail
934 * if wrong parameters were passed or the pad was already in the
940 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
941 GstPadBlockCallback callback, gpointer user_data)
943 gboolean was_blocked = FALSE;
945 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
947 GST_OBJECT_LOCK (pad);
949 was_blocked = GST_PAD_IS_BLOCKED (pad);
951 if (G_UNLIKELY (was_blocked == blocked))
952 goto had_right_state;
955 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
957 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
958 pad->block_callback = callback;
959 pad->block_data = user_data;
961 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
962 GST_PAD_BLOCK_WAIT (pad);
963 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
966 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
968 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
970 pad->block_callback = callback;
971 pad->block_data = user_data;
974 GST_PAD_BLOCK_SIGNAL (pad);
976 GST_PAD_BLOCK_SIGNAL (pad);
977 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
978 GST_PAD_BLOCK_WAIT (pad);
979 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
982 GST_OBJECT_UNLOCK (pad);
988 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
989 "pad was in right state (%d)", was_blocked);
990 GST_OBJECT_UNLOCK (pad);
997 * gst_pad_set_blocked:
998 * @pad: the #GstPad to block or unblock
999 * @blocked: boolean indicating we should block or unblock
1001 * Blocks or unblocks the dataflow on a pad. This function is
1002 * a shortcut for gst_pad_set_blocked_async() with a NULL
1005 * Returns: TRUE if the pad could be blocked. This function can fail
1006 * wrong parameters were passed or the pad was already in the
1012 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
1014 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
1018 * gst_pad_is_blocked:
1019 * @pad: the #GstPad to query
1021 * Checks if the pad is blocked or not. This function returns the
1022 * last requested state of the pad. It is not certain that the pad
1023 * is actually blocked at this point.
1025 * Returns: TRUE if the pad is blocked.
1030 gst_pad_is_blocked (GstPad * pad)
1032 gboolean result = FALSE;
1034 g_return_val_if_fail (GST_IS_PAD (pad), result);
1036 GST_OBJECT_LOCK (pad);
1037 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
1038 GST_OBJECT_UNLOCK (pad);
1044 * gst_pad_set_activate_function:
1046 * @activate: the #GstPadActivateFunction to set.
1048 * Sets the given activate function for @pad. The activate function will
1049 * dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
1050 * the actual activation. Only makes sense to set on sink pads.
1052 * Call this function if your sink pad can start a pull-based task.
1055 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
1057 g_return_if_fail (GST_IS_PAD (pad));
1059 GST_PAD_ACTIVATEFUNC (pad) = activate;
1060 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
1061 GST_DEBUG_FUNCPTR_NAME (activate));
1065 * gst_pad_set_activatepull_function:
1067 * @activatepull: the #GstPadActivateModeFunction to set.
1069 * Sets the given activate_pull function for the pad. An activate_pull function
1070 * prepares the element and any upstream connections for pulling. See XXX
1071 * part-activation.txt for details.
1074 gst_pad_set_activatepull_function (GstPad * pad,
1075 GstPadActivateModeFunction activatepull)
1077 g_return_if_fail (GST_IS_PAD (pad));
1079 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
1080 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
1081 GST_DEBUG_FUNCPTR_NAME (activatepull));
1085 * gst_pad_set_activatepush_function:
1087 * @activatepush: the #GstPadActivateModeFunction to set.
1089 * Sets the given activate_push function for the pad. An activate_push function
1090 * prepares the element for pushing. See XXX part-activation.txt for details.
1093 gst_pad_set_activatepush_function (GstPad * pad,
1094 GstPadActivateModeFunction activatepush)
1096 g_return_if_fail (GST_IS_PAD (pad));
1098 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1099 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
1100 GST_DEBUG_FUNCPTR_NAME (activatepush));
1104 * gst_pad_set_chain_function:
1105 * @pad: a sink #GstPad.
1106 * @chain: the #GstPadChainFunction to set.
1108 * Sets the given chain function for the pad. The chain function is called to
1109 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1112 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1114 g_return_if_fail (GST_IS_PAD (pad));
1115 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
1117 GST_PAD_CHAINFUNC (pad) = chain;
1118 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
1119 GST_DEBUG_FUNCPTR_NAME (chain));
1123 * gst_pad_set_getrange_function:
1124 * @pad: a source #GstPad.
1125 * @get: the #GstPadGetRangeFunction to set.
1127 * Sets the given getrange function for the pad. The getrange function is called to
1128 * produce a new #GstBuffer to start the processing pipeline. see
1129 * #GstPadGetRangeFunction for a description of the getrange function.
1132 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1134 g_return_if_fail (GST_IS_PAD (pad));
1135 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1137 GST_PAD_GETRANGEFUNC (pad) = get;
1139 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
1140 GST_DEBUG_FUNCPTR_NAME (get));
1144 * gst_pad_set_checkgetrange_function:
1145 * @pad: a source #GstPad.
1146 * @check: the #GstPadCheckGetRangeFunction to set.
1148 * Sets the given checkgetrange function for the pad. Implement this function on
1149 * a pad if you dynamically support getrange based scheduling on the pad.
1152 gst_pad_set_checkgetrange_function (GstPad * pad,
1153 GstPadCheckGetRangeFunction check)
1155 g_return_if_fail (GST_IS_PAD (pad));
1156 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1158 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1160 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
1161 GST_DEBUG_FUNCPTR_NAME (check));
1165 * gst_pad_set_event_function:
1166 * @pad: a source #GstPad.
1167 * @event: the #GstPadEventFunction to set.
1169 * Sets the given event handler for the pad.
1172 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1174 g_return_if_fail (GST_IS_PAD (pad));
1176 GST_PAD_EVENTFUNC (pad) = event;
1178 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
1179 GST_DEBUG_FUNCPTR_NAME (event));
1183 * gst_pad_set_query_function:
1184 * @pad: a #GstPad of either direction.
1185 * @query: the #GstPadQueryFunction to set.
1187 * Set the given query function for the pad.
1190 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1192 g_return_if_fail (GST_IS_PAD (pad));
1194 GST_PAD_QUERYFUNC (pad) = query;
1196 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
1197 GST_DEBUG_FUNCPTR_NAME (query));
1201 * gst_pad_set_query_type_function:
1202 * @pad: a #GstPad of either direction.
1203 * @type_func: the #GstPadQueryTypeFunction to set.
1205 * Set the given query type function for the pad.
1208 gst_pad_set_query_type_function (GstPad * pad,
1209 GstPadQueryTypeFunction type_func)
1211 g_return_if_fail (GST_IS_PAD (pad));
1213 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1215 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
1216 GST_DEBUG_FUNCPTR_NAME (type_func));
1220 * gst_pad_get_query_types:
1223 * Get an array of supported queries that can be performed
1226 * Returns: a zero-terminated array of #GstQueryType.
1228 const GstQueryType *
1229 gst_pad_get_query_types (GstPad * pad)
1231 GstPadQueryTypeFunction func;
1233 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1235 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1247 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1249 *data = gst_pad_get_query_types (pad);
1255 * gst_pad_get_query_types_default:
1258 * Invoke the default dispatcher for the query types on
1261 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1262 * internally-linked pads has a query types function.
1264 const GstQueryType *
1265 gst_pad_get_query_types_default (GstPad * pad)
1267 GstQueryType *result = NULL;
1269 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1271 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1272 gst_pad_get_query_types_dispatcher, &result);
1278 * gst_pad_set_internal_link_function:
1279 * @pad: a #GstPad of either direction.
1280 * @intlink: the #GstPadIntLinkFunction to set.
1282 * Sets the given internal link function for the pad.
1285 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1287 g_return_if_fail (GST_IS_PAD (pad));
1289 GST_PAD_INTLINKFUNC (pad) = intlink;
1290 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
1291 GST_DEBUG_FUNCPTR_NAME (intlink));
1295 * gst_pad_set_link_function:
1297 * @link: the #GstPadLinkFunction to set.
1299 * Sets the given link function for the pad. It will be called when
1300 * the pad is linked with another pad.
1302 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1305 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1306 * cannot be made for some reason.
1308 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1309 * of the peer sink pad, if present.
1312 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1314 g_return_if_fail (GST_IS_PAD (pad));
1316 GST_PAD_LINKFUNC (pad) = link;
1317 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
1318 GST_DEBUG_FUNCPTR_NAME (link));
1322 * gst_pad_set_unlink_function:
1324 * @unlink: the #GstPadUnlinkFunction to set.
1326 * Sets the given unlink function for the pad. It will be called
1327 * when the pad is unlinked.
1330 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1332 g_return_if_fail (GST_IS_PAD (pad));
1334 GST_PAD_UNLINKFUNC (pad) = unlink;
1335 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
1336 GST_DEBUG_FUNCPTR_NAME (unlink));
1340 * gst_pad_set_getcaps_function:
1342 * @getcaps: the #GstPadGetCapsFunction to set.
1344 * Sets the given getcaps function for the pad. @getcaps should return the
1345 * allowable caps for a pad in the context of the element's state, its link to
1346 * other elements, and the devices or files it has opened. These caps must be a
1347 * subset of the pad template caps. In the NULL state with no links, @getcaps
1348 * should ideally return the same caps as the pad template. In rare
1349 * circumstances, an object property can affect the caps returned by @getcaps,
1350 * but this is discouraged.
1352 * You do not need to call this function if @pad's allowed caps are always the
1353 * same as the pad template caps. This can only be true if the padtemplate
1354 * has fixed simple caps.
1356 * For most filters, the caps returned by @getcaps is directly affected by the
1357 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1358 * the srcpad's getcaps function is directly related to the stream data. Again,
1359 * @getcaps should return the most specific caps it reasonably can, since this
1360 * helps with autoplugging.
1362 * Note that the return value from @getcaps is owned by the caller, so the caller
1363 * should unref the caps after usage.
1366 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1368 g_return_if_fail (GST_IS_PAD (pad));
1370 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1371 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
1372 GST_DEBUG_FUNCPTR_NAME (getcaps));
1376 * gst_pad_set_acceptcaps_function:
1378 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1380 * Sets the given acceptcaps function for the pad. The acceptcaps function
1381 * will be called to check if the pad can accept the given caps. Setting the
1382 * acceptcaps function to NULL restores the default behaviour of allowing
1383 * any caps that matches the caps from gst_pad_get_caps.
1386 gst_pad_set_acceptcaps_function (GstPad * pad,
1387 GstPadAcceptCapsFunction acceptcaps)
1389 g_return_if_fail (GST_IS_PAD (pad));
1391 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1392 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
1393 GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1397 * gst_pad_set_fixatecaps_function:
1399 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1401 * Sets the given fixatecaps function for the pad. The fixatecaps function
1402 * will be called whenever the default values for a GstCaps needs to be
1406 gst_pad_set_fixatecaps_function (GstPad * pad,
1407 GstPadFixateCapsFunction fixatecaps)
1409 g_return_if_fail (GST_IS_PAD (pad));
1411 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1412 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
1413 GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1417 * gst_pad_set_setcaps_function:
1419 * @setcaps: the #GstPadSetCapsFunction to set.
1421 * Sets the given setcaps function for the pad. The setcaps function
1422 * will be called whenever a buffer with a new media type is pushed or
1423 * pulled from the pad. The pad/element needs to update its internal
1424 * structures to process the new media type. If this new type is not
1425 * acceptable, the setcaps function should return FALSE.
1428 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1430 g_return_if_fail (GST_IS_PAD (pad));
1432 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1433 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
1434 GST_DEBUG_FUNCPTR_NAME (setcaps));
1438 * gst_pad_set_bufferalloc_function:
1439 * @pad: a sink #GstPad.
1440 * @bufalloc: the #GstPadBufferAllocFunction to set.
1442 * Sets the given bufferalloc function for the pad. Note that the
1443 * bufferalloc function can only be set on sinkpads.
1446 gst_pad_set_bufferalloc_function (GstPad * pad,
1447 GstPadBufferAllocFunction bufalloc)
1449 g_return_if_fail (GST_IS_PAD (pad));
1450 g_return_if_fail (GST_PAD_IS_SINK (pad));
1452 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1453 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
1454 GST_DEBUG_FUNCPTR_NAME (bufalloc));
1459 * @srcpad: the source #GstPad to unlink.
1460 * @sinkpad: the sink #GstPad to unlink.
1462 * Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
1465 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1466 * the pads were not linked together.
1471 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1473 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1474 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1476 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1477 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1478 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1480 GST_OBJECT_LOCK (srcpad);
1482 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1485 GST_OBJECT_LOCK (sinkpad);
1487 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1490 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1491 goto not_linked_together;
1493 if (GST_PAD_UNLINKFUNC (srcpad)) {
1494 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1496 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1497 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1500 /* first clear peers */
1501 GST_PAD_PEER (srcpad) = NULL;
1502 GST_PAD_PEER (sinkpad) = NULL;
1504 GST_OBJECT_UNLOCK (sinkpad);
1505 GST_OBJECT_UNLOCK (srcpad);
1507 /* fire off a signal to each of the pads telling them
1508 * that they've been unlinked */
1509 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1510 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1512 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1513 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1519 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1520 GST_OBJECT_UNLOCK (srcpad);
1525 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1526 GST_OBJECT_UNLOCK (sinkpad);
1527 GST_OBJECT_UNLOCK (srcpad);
1530 not_linked_together:
1532 /* we do not emit a warning in this case because unlinking cannot
1533 * be made MT safe.*/
1534 GST_OBJECT_UNLOCK (sinkpad);
1535 GST_OBJECT_UNLOCK (srcpad);
1541 * gst_pad_is_linked:
1542 * @pad: pad to check
1544 * Checks if a @pad is linked to another pad or not.
1546 * Returns: TRUE if the pad is linked, FALSE otherwise.
1551 gst_pad_is_linked (GstPad * pad)
1555 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1557 GST_OBJECT_LOCK (pad);
1558 result = (GST_PAD_PEER (pad) != NULL);
1559 GST_OBJECT_UNLOCK (pad);
1564 /* get the caps from both pads and see if the intersection
1567 * This function should be called with the pad LOCK on both
1571 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1577 srccaps = gst_pad_get_caps_unlocked (src);
1578 sinkcaps = gst_pad_get_caps_unlocked (sink);
1580 GST_CAT_DEBUG (GST_CAT_CAPS, "src caps %" GST_PTR_FORMAT, srccaps);
1581 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1583 /* if we have caps on both pads we can check the intersection. If one
1584 * of the caps is NULL, we return TRUE. */
1585 if (srccaps == NULL || sinkcaps == NULL)
1588 icaps = gst_caps_intersect (srccaps, sinkcaps);
1589 gst_caps_unref (srccaps);
1590 gst_caps_unref (sinkcaps);
1595 GST_CAT_DEBUG (GST_CAT_CAPS,
1596 "intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
1598 if (gst_caps_is_empty (icaps))
1601 gst_caps_unref (icaps);
1606 /* incompatible cases */
1609 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection gave NULL");
1614 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is EMPTY");
1615 gst_caps_unref (icaps);
1620 /* check if the grandparents of both pads are the same.
1621 * This check is required so that we don't try to link
1622 * pads from elements in different bins without ghostpads.
1624 * The LOCK should be held on both pads
1627 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1629 GstObject *psrc, *psink;
1630 gboolean res = TRUE;
1632 psrc = GST_OBJECT_PARENT (src);
1633 psink = GST_OBJECT_PARENT (sink);
1635 /* if one of the pads has no parent, we allow the link */
1636 if (psrc && psink) {
1637 /* if the parents are the same, we have a loop */
1638 if (G_UNLIKELY (psrc == psink))
1641 /* if they both have a parent, we check the grandparents */
1642 psrc = gst_object_get_parent (psrc);
1643 psink = gst_object_get_parent (psink);
1645 if (G_UNLIKELY (psrc != psink)) {
1646 /* if they have grandparents but they are not the same */
1647 GST_CAT_DEBUG (GST_CAT_CAPS,
1648 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1649 GST_PTR_FORMAT, psrc, psink);
1653 gst_object_unref (psrc);
1655 gst_object_unref (psink);
1663 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1670 /* FIXME leftover from an attempt at refactoring... */
1671 /* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
1672 * the two pads will be locked in the srcpad, sinkpad order. */
1673 static GstPadLinkReturn
1674 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1676 /* generic checks */
1677 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
1678 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
1680 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1681 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1683 GST_OBJECT_LOCK (srcpad);
1685 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1688 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1689 goto src_was_linked;
1691 GST_OBJECT_LOCK (sinkpad);
1693 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1696 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1697 goto sink_was_linked;
1699 /* check hierarchy, pads can only be linked if the grandparents
1701 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1702 goto wrong_hierarchy;
1704 /* check pad caps for non-empty intersection */
1705 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1708 /* FIXME check pad scheduling for non-empty intersection */
1710 return GST_PAD_LINK_OK;
1714 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1715 GST_OBJECT_UNLOCK (srcpad);
1716 return GST_PAD_LINK_WRONG_DIRECTION;
1720 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
1721 GST_DEBUG_PAD_NAME (srcpad),
1722 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1723 /* we do not emit a warning in this case because unlinking cannot
1724 * be made MT safe.*/
1725 GST_OBJECT_UNLOCK (srcpad);
1726 return GST_PAD_LINK_WAS_LINKED;
1730 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1731 GST_OBJECT_UNLOCK (sinkpad);
1732 GST_OBJECT_UNLOCK (srcpad);
1733 return GST_PAD_LINK_WRONG_DIRECTION;
1737 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
1738 GST_DEBUG_PAD_NAME (sinkpad),
1739 GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
1740 /* we do not emit a warning in this case because unlinking cannot
1741 * be made MT safe.*/
1742 GST_OBJECT_UNLOCK (sinkpad);
1743 GST_OBJECT_UNLOCK (srcpad);
1744 return GST_PAD_LINK_WAS_LINKED;
1748 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1749 GST_OBJECT_UNLOCK (sinkpad);
1750 GST_OBJECT_UNLOCK (srcpad);
1751 return GST_PAD_LINK_WRONG_HIERARCHY;
1755 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1756 GST_OBJECT_UNLOCK (sinkpad);
1757 GST_OBJECT_UNLOCK (srcpad);
1758 return GST_PAD_LINK_NOFORMAT;
1764 * @srcpad: the source #GstPad to link.
1765 * @sinkpad: the sink #GstPad to link.
1767 * Links the source pad and the sink pad.
1769 * Returns: A result code indicating if the connection worked or
1775 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1777 GstPadLinkReturn result;
1779 /* prepare will also lock the two pads */
1780 result = gst_pad_link_prepare (srcpad, sinkpad);
1782 if (result != GST_PAD_LINK_OK)
1783 goto prepare_failed;
1785 /* must set peers before calling the link function */
1786 GST_PAD_PEER (srcpad) = sinkpad;
1787 GST_PAD_PEER (sinkpad) = srcpad;
1789 GST_OBJECT_UNLOCK (sinkpad);
1790 GST_OBJECT_UNLOCK (srcpad);
1792 /* FIXME released the locks here, concurrent thread might link
1793 * something else. */
1794 if (GST_PAD_LINKFUNC (srcpad)) {
1795 /* this one will call the peer link function */
1796 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
1797 } else if (GST_PAD_LINKFUNC (sinkpad)) {
1798 /* if no source link function, we need to call the sink link
1799 * function ourselves. */
1800 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
1802 result = GST_PAD_LINK_OK;
1805 GST_OBJECT_LOCK (srcpad);
1806 GST_OBJECT_LOCK (sinkpad);
1808 if (result == GST_PAD_LINK_OK) {
1809 GST_OBJECT_UNLOCK (sinkpad);
1810 GST_OBJECT_UNLOCK (srcpad);
1812 /* fire off a signal to each of the pads telling them
1813 * that they've been linked */
1814 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
1815 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
1817 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
1818 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1820 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
1821 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1823 GST_PAD_PEER (srcpad) = NULL;
1824 GST_PAD_PEER (sinkpad) = NULL;
1826 GST_OBJECT_UNLOCK (sinkpad);
1827 GST_OBJECT_UNLOCK (srcpad);
1838 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
1840 GstPadTemplate **template_p;
1842 /* this function would need checks if it weren't static */
1844 GST_OBJECT_LOCK (pad);
1845 template_p = &pad->padtemplate;
1846 gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
1847 GST_OBJECT_UNLOCK (pad);
1850 gst_pad_template_pad_created (templ, pad);
1854 * gst_pad_get_pad_template:
1857 * Gets the template for @pad.
1859 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
1860 * if this pad has no template.
1862 * FIXME: currently returns an unrefcounted padtemplate.
1865 gst_pad_get_pad_template (GstPad * pad)
1867 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1869 return GST_PAD_PAD_TEMPLATE (pad);
1873 /* should be called with the pad LOCK held */
1874 /* refs the caps, so caller is responsible for getting it unreffed */
1876 gst_pad_get_caps_unlocked (GstPad * pad)
1878 GstCaps *result = NULL;
1880 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
1882 if (GST_PAD_GETCAPSFUNC (pad)) {
1883 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1884 "dispatching to pad getcaps function");
1886 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
1887 GST_OBJECT_UNLOCK (pad);
1888 result = GST_PAD_GETCAPSFUNC (pad) (pad);
1889 GST_OBJECT_LOCK (pad);
1890 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
1892 if (result == NULL) {
1893 g_critical ("pad %s:%s returned NULL caps from getcaps function",
1894 GST_DEBUG_PAD_NAME (pad));
1896 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1897 "pad getcaps returned %" GST_PTR_FORMAT, result);
1898 #ifndef G_DISABLE_ASSERT
1899 /* check that the returned caps are a real subset of the template caps */
1900 if (GST_PAD_PAD_TEMPLATE (pad)) {
1901 const GstCaps *templ_caps =
1902 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
1903 if (!gst_caps_is_subset (result, templ_caps)) {
1906 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
1907 "pad returned caps %" GST_PTR_FORMAT
1908 " which are not a real subset of its template caps %"
1909 GST_PTR_FORMAT, result, templ_caps);
1911 ("pad %s:%s returned caps that are not a real subset of its template caps",
1912 GST_DEBUG_PAD_NAME (pad));
1913 temp = gst_caps_intersect (templ_caps, result);
1914 gst_caps_unref (result);
1922 if (GST_PAD_PAD_TEMPLATE (pad)) {
1923 GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
1925 result = GST_PAD_TEMPLATE_CAPS (templ);
1926 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1927 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
1930 result = gst_caps_ref (result);
1933 if (GST_PAD_CAPS (pad)) {
1934 result = GST_PAD_CAPS (pad);
1936 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1937 "using pad caps %p %" GST_PTR_FORMAT, result, result);
1939 result = gst_caps_ref (result);
1943 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
1944 result = gst_caps_new_empty ();
1952 * @pad: a #GstPad to get the capabilities of.
1954 * Gets the capabilities this pad can produce or consume.
1955 * Note that this method doesn't necessarily return the caps set by
1956 * gst_pad_set_caps() - use #GST_PAD_CAPS for that instead.
1957 * gst_pad_get_caps returns all possible caps a pad can operate with, using
1958 * the pad's get_caps function;
1959 * this returns the pad template caps if not explicitly set.
1961 * Returns: a newly allocated copy of the #GstCaps of this pad.
1966 gst_pad_get_caps (GstPad * pad)
1968 GstCaps *result = NULL;
1970 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1972 GST_OBJECT_LOCK (pad);
1974 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
1976 result = gst_pad_get_caps_unlocked (pad);
1977 GST_OBJECT_UNLOCK (pad);
1983 * gst_pad_peer_get_caps:
1984 * @pad: a #GstPad to get the peer capabilities of.
1986 * Gets the capabilities of the peer connected to this pad.
1988 * Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
1989 * gst_caps_unref to get rid of it. this function returns NULL if there is no
1993 gst_pad_peer_get_caps (GstPad * pad)
1996 GstCaps *result = NULL;
1998 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2000 GST_OBJECT_LOCK (pad);
2002 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2004 peerpad = GST_PAD_PEER (pad);
2005 if (G_UNLIKELY (peerpad == NULL))
2008 gst_object_ref (peerpad);
2009 GST_OBJECT_UNLOCK (pad);
2011 result = gst_pad_get_caps (peerpad);
2013 gst_object_unref (peerpad);
2019 GST_OBJECT_UNLOCK (pad);
2025 fixate_value (GValue * dest, const GValue * src)
2027 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
2028 g_value_init (dest, G_TYPE_INT);
2029 g_value_set_int (dest, gst_value_get_int_range_min (src));
2030 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
2031 g_value_init (dest, G_TYPE_DOUBLE);
2032 g_value_set_double (dest, gst_value_get_double_range_min (src));
2033 } else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
2034 gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
2035 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
2036 GValue temp = { 0 };
2038 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
2039 if (!fixate_value (dest, &temp))
2040 gst_value_init_and_copy (dest, &temp);
2041 g_value_unset (&temp);
2042 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
2043 gboolean res = FALSE;
2046 g_value_init (dest, GST_TYPE_ARRAY);
2047 for (n = 0; n < gst_value_array_get_size (src); n++) {
2049 const GValue *orig_kid = gst_value_array_get_value (src, n);
2051 if (!fixate_value (&kid, orig_kid))
2052 gst_value_init_and_copy (&kid, orig_kid);
2055 gst_value_array_append_value (dest, &kid);
2056 g_value_unset (&kid);
2060 g_value_unset (dest);
2071 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
2073 GstStructure *s = data;
2076 if (fixate_value (&v, value)) {
2077 gst_structure_id_set_value (s, field_id, &v);
2085 * gst_pad_fixate_caps:
2086 * @pad: a #GstPad to fixate
2087 * @caps: the #GstCaps to fixate
2089 * Fixate a caps on the given pad. Modifies the caps in place, so you should
2090 * make sure that the caps are actually writable (see gst_caps_make_writable()).
2093 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
2095 GstPadFixateCapsFunction fixatefunc;
2098 g_return_if_fail (GST_IS_PAD (pad));
2099 g_return_if_fail (caps != NULL);
2101 if (gst_caps_is_fixed (caps))
2104 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
2106 fixatefunc (pad, caps);
2109 /* default fixation */
2110 for (n = 0; n < gst_caps_get_size (caps); n++) {
2111 GstStructure *s = gst_caps_get_structure (caps, n);
2113 gst_structure_foreach (s, gst_pad_default_fixate, s);
2117 /* Default accept caps implementation just checks against
2118 * against the allowed caps for the pad */
2120 gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
2122 /* get the caps and see if it intersects to something
2126 gboolean result = FALSE;
2128 allowed = gst_pad_get_caps (pad);
2130 intersect = gst_caps_intersect (allowed, caps);
2132 result = !gst_caps_is_empty (intersect);
2134 gst_caps_unref (allowed);
2135 gst_caps_unref (intersect);
2142 * gst_pad_accept_caps:
2143 * @pad: a #GstPad to check
2144 * @caps: a #GstCaps to check on the pad
2146 * Check if the given pad accepts the caps.
2148 * Returns: TRUE if the pad can accept the caps.
2151 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2154 GstPadAcceptCapsFunction acceptfunc;
2155 GstCaps *existing = NULL;
2157 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2159 /* any pad can be unnegotiated */
2163 /* lock for checking the existing caps */
2164 GST_OBJECT_LOCK (pad);
2165 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2166 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
2167 /* The current caps on a pad are trivially acceptable */
2168 if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
2169 if (caps == existing || gst_caps_is_equal (caps, existing))
2172 GST_OBJECT_UNLOCK (pad);
2174 if (G_LIKELY (acceptfunc)) {
2175 /* we can call the function */
2176 result = acceptfunc (pad, caps);
2178 /* Only null if the element explicitly unset it */
2179 result = gst_pad_acceptcaps_default (pad, caps);
2185 GST_OBJECT_UNLOCK (pad);
2191 * gst_pad_peer_accept_caps:
2192 * @pad: a #GstPad to check the peer of
2193 * @caps: a #GstCaps to check on the pad
2195 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2198 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2201 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2206 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2208 GST_OBJECT_LOCK (pad);
2210 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
2212 peerpad = GST_PAD_PEER (pad);
2213 if (G_UNLIKELY (peerpad == NULL))
2216 result = gst_pad_accept_caps (peerpad, caps);
2217 GST_OBJECT_UNLOCK (pad);
2223 GST_OBJECT_UNLOCK (pad);
2230 * @pad: a #GstPad to set the capabilities of.
2231 * @caps: a #GstCaps to set.
2233 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2234 * caps on the pad will be unreffed. This function refs the caps so you should
2235 * unref if as soon as you don't need it anymore.
2236 * It is possible to set NULL caps, which will make the pad unnegotiated
2239 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2240 * or bad parameters were provided to this function.
2245 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2247 GstPadSetCapsFunction setcaps;
2250 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2251 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2253 GST_OBJECT_LOCK (pad);
2254 existing = GST_PAD_CAPS (pad);
2255 if (existing == caps)
2258 if (gst_caps_is_equal (caps, existing))
2259 goto setting_same_caps;
2261 setcaps = GST_PAD_SETCAPSFUNC (pad);
2263 /* call setcaps function to configure the pad only if the
2264 * caps is not NULL */
2265 if (setcaps != NULL && caps) {
2266 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2267 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2268 GST_OBJECT_UNLOCK (pad);
2269 if (!setcaps (pad, caps))
2271 GST_OBJECT_LOCK (pad);
2272 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2274 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
2278 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2279 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %" GST_PTR_FORMAT, caps);
2280 GST_OBJECT_UNLOCK (pad);
2282 g_object_notify (G_OBJECT (pad), "caps");
2288 GST_OBJECT_UNLOCK (pad);
2293 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2294 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2295 "caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
2296 GST_OBJECT_UNLOCK (pad);
2303 GST_OBJECT_LOCK (pad);
2304 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2305 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2306 "caps %" GST_PTR_FORMAT " could not be set", caps);
2307 GST_OBJECT_UNLOCK (pad);
2314 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2316 GstPadSetCapsFunction setcaps;
2319 setcaps = GST_PAD_SETCAPSFUNC (pad);
2321 /* See if pad accepts the caps - only needed if
2322 * no setcaps function */
2323 if (setcaps == NULL)
2324 if (!gst_pad_accept_caps (pad, caps))
2327 /* set caps on pad if call succeeds */
2328 res = gst_pad_set_caps (pad, caps);
2329 /* no need to unref the caps here, set_caps takes a ref and
2330 * our ref goes away when we leave this function. */
2336 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2337 "caps %" GST_PTR_FORMAT " not accepted", caps);
2342 /* returns TRUE if the src pad could be configured to accept the given caps */
2344 gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
2346 GstPadSetCapsFunction setcaps;
2349 setcaps = GST_PAD_SETCAPSFUNC (pad);
2351 /* See if pad accepts the caps - only needed if
2352 * no setcaps function */
2353 if (setcaps == NULL)
2354 if (!gst_pad_accept_caps (pad, caps))
2358 res = gst_pad_set_caps (pad, caps);
2366 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2367 "caps %" GST_PTR_FORMAT " not accepted", caps);
2373 * gst_pad_get_pad_template_caps:
2374 * @pad: a #GstPad to get the template capabilities from.
2376 * Gets the capabilities for @pad's template.
2378 * Returns: the #GstCaps of this pad template. If you intend to keep a reference
2379 * on the caps, make a copy (see gst_caps_copy ()).
2382 gst_pad_get_pad_template_caps (GstPad * pad)
2384 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2386 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2388 if (GST_PAD_PAD_TEMPLATE (pad))
2389 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2391 return gst_static_caps_get (&anycaps);
2397 * @pad: a #GstPad to get the peer of.
2399 * Gets the peer of @pad. This function refs the peer pad so
2400 * you need to unref it after use.
2402 * Returns: the peer #GstPad. Unref after usage.
2407 gst_pad_get_peer (GstPad * pad)
2411 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2413 GST_OBJECT_LOCK (pad);
2414 result = GST_PAD_PEER (pad);
2416 gst_object_ref (result);
2417 GST_OBJECT_UNLOCK (pad);
2423 * gst_pad_get_allowed_caps:
2424 * @srcpad: a #GstPad, it must a a source pad.
2426 * Gets the capabilities of the allowed media types that can flow through
2427 * @srcpad and its peer. The pad must be a source pad.
2428 * The caller must free the resulting caps.
2430 * Returns: the allowed #GstCaps of the pad link. Free the caps when
2431 * you no longer need it. This function returns NULL when the @srcpad has no
2437 gst_pad_get_allowed_caps (GstPad * srcpad)
2444 g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
2445 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
2447 GST_OBJECT_LOCK (srcpad);
2449 peer = GST_PAD_PEER (srcpad);
2450 if (G_UNLIKELY (peer == NULL))
2453 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "getting allowed caps");
2455 gst_object_ref (peer);
2456 GST_OBJECT_UNLOCK (srcpad);
2457 mycaps = gst_pad_get_caps (srcpad);
2459 peercaps = gst_pad_get_caps (peer);
2460 gst_object_unref (peer);
2462 caps = gst_caps_intersect (mycaps, peercaps);
2463 gst_caps_unref (peercaps);
2464 gst_caps_unref (mycaps);
2466 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, srcpad, "allowed caps %" GST_PTR_FORMAT,
2473 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "no peer");
2474 GST_OBJECT_UNLOCK (srcpad);
2481 * gst_pad_get_negotiated_caps:
2484 * Gets the capabilities of the media type that currently flows through @pad
2487 * This function can be used on both src and sinkpads. Note that srcpads are
2488 * always negotiated before sinkpads so it is possible that the negotiated caps
2489 * on the srcpad do not match the negotiated caps of the peer.
2491 * Returns: the negotiated #GstCaps of the pad link. Free the caps when
2492 * you no longer need it. This function returns NULL when the @pad has no
2493 * peer or is not negotiated yet.
2498 gst_pad_get_negotiated_caps (GstPad * pad)
2503 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2505 GST_OBJECT_LOCK (pad);
2507 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2510 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
2512 caps = GST_PAD_CAPS (pad);
2514 gst_caps_ref (caps);
2515 GST_OBJECT_UNLOCK (pad);
2517 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
2524 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2525 GST_OBJECT_UNLOCK (pad);
2531 /* calls the buffer_alloc function on the given pad */
2532 static GstFlowReturn
2533 gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
2534 GstCaps * caps, GstBuffer ** buf)
2537 GstPadBufferAllocFunction bufferallocfunc;
2539 GST_OBJECT_LOCK (pad);
2540 /* when the pad is flushing we cannot give a buffer */
2541 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2544 if (offset == GST_BUFFER_OFFSET_NONE) {
2545 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2546 "calling bufferallocfunc &%s (@%p) for size %d offset NONE",
2547 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), &bufferallocfunc, size);
2549 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2550 "calling bufferallocfunc &%s (@%p) of for size %d offset %"
2551 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2552 &bufferallocfunc, size, offset);
2554 GST_OBJECT_UNLOCK (pad);
2556 /* G_LIKELY for now since most elements don't implement a buffer alloc
2557 * function and there is no default alloc proxy function as this is usually
2559 if (G_LIKELY ((bufferallocfunc = pad->bufferallocfunc) == NULL))
2562 ret = bufferallocfunc (pad, offset, size, caps, buf);
2563 if (G_UNLIKELY (ret != GST_FLOW_OK))
2565 /* no error, but NULL buffer means fallback to the default */
2566 if (G_UNLIKELY (*buf == NULL))
2569 /* If the buffer alloc function didn't set up the caps like it should,
2571 if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
2572 GST_WARNING_OBJECT (pad,
2573 "Buffer allocation function did not set caps. Setting");
2574 gst_buffer_set_caps (*buf, caps);
2580 /* pad was flushing */
2581 GST_OBJECT_UNLOCK (pad);
2582 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
2583 return GST_FLOW_WRONG_STATE;
2587 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2588 "alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
2593 /* fallback case, allocate a buffer of our own, add pad caps. */
2594 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
2596 *buf = gst_buffer_new_and_alloc (size);
2597 GST_BUFFER_OFFSET (*buf) = offset;
2598 gst_buffer_set_caps (*buf, caps);
2604 static GstFlowReturn
2605 gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
2606 GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
2610 gboolean caps_changed;
2612 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2613 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2614 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2616 GST_OBJECT_LOCK (pad);
2617 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2618 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
2621 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2624 gst_object_ref (peer);
2625 GST_OBJECT_UNLOCK (pad);
2627 ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
2628 gst_object_unref (peer);
2630 if (G_UNLIKELY (ret != GST_FLOW_OK))
2633 /* FIXME, move capnego this into a base class? */
2634 caps = GST_BUFFER_CAPS (*buf);
2636 /* Lock for checking caps, pretty pointless as the _pad_push() function might
2637 * change it concurrently, one of the problems with automatic caps setting in
2638 * pad_alloc_and_set_caps. Worst case, if does a check too much, but only when
2639 * there is heavy renegotiation going on in both directions. */
2640 GST_OBJECT_LOCK (pad);
2641 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2642 GST_OBJECT_UNLOCK (pad);
2644 /* we got a new datatype on the pad, see if it can handle it */
2645 if (G_UNLIKELY (caps_changed)) {
2646 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
2647 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, setcaps)))
2648 goto not_negotiated;
2654 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
2655 GST_OBJECT_UNLOCK (pad);
2660 /* pad has no peer */
2661 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2662 "called bufferallocfunc but had no peer");
2663 GST_OBJECT_UNLOCK (pad);
2664 return GST_FLOW_NOT_LINKED;
2668 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2669 "alloc function returned error %s", gst_flow_get_name (ret));
2674 gst_buffer_unref (*buf);
2676 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2677 "alloc function returned unacceptable buffer");
2678 return GST_FLOW_NOT_NEGOTIATED;
2683 * gst_pad_alloc_buffer:
2684 * @pad: a source #GstPad
2685 * @offset: the offset of the new buffer in the stream
2686 * @size: the size of the new buffer
2687 * @caps: the caps of the new buffer
2688 * @buf: a newly allocated buffer
2690 * Allocates a new, empty buffer optimized to push to pad @pad. This
2691 * function only works if @pad is a source pad and has a peer.
2693 * A new, empty #GstBuffer will be put in the @buf argument.
2694 * You need to check the caps of the buffer after performing this
2695 * function and renegotiate to the format if needed.
2697 * Returns: a result code indicating success of the operation. Any
2698 * result code other than #GST_FLOW_OK is an error and @buf should
2700 * An error can occur if the pad is not connected or when the downstream
2701 * peer elements cannot provide an acceptable buffer.
2706 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
2709 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
2713 * gst_pad_alloc_buffer_and_set_caps:
2714 * @pad: a source #GstPad
2715 * @offset: the offset of the new buffer in the stream
2716 * @size: the size of the new buffer
2717 * @caps: the caps of the new buffer
2718 * @buf: a newly allocated buffer
2720 * In addition to the function gst_pad_alloc_buffer(), this function
2721 * automatically calls gst_pad_set_caps() when the caps of the
2722 * newly allocated buffer are different from the @pad caps.
2724 * Returns: a result code indicating success of the operation. Any
2725 * result code other than #GST_FLOW_OK is an error and @buf should
2727 * An error can occur if the pad is not connected or when the downstream
2728 * peer elements cannot provide an acceptable buffer.
2733 gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
2734 GstCaps * caps, GstBuffer ** buf)
2736 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
2740 * gst_pad_get_internal_links_default:
2741 * @pad: the #GstPad to get the internal links of.
2743 * Gets a list of pads to which the given pad is linked to
2744 * inside of the parent element.
2745 * This is the default handler, and thus returns a list of all of the
2746 * pads inside the parent element with opposite direction.
2747 * The caller must free this list after use.
2749 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
2754 gst_pad_get_internal_links_default (GstPad * pad)
2759 GstPadDirection direction;
2761 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2763 direction = pad->direction;
2765 parent = GST_PAD_PARENT (pad);
2769 parent_pads = parent->pads;
2771 while (parent_pads) {
2772 GstPad *parent_pad = GST_PAD_CAST (parent_pads->data);
2774 if (parent_pad->direction != direction) {
2775 res = g_list_prepend (res, parent_pad);
2778 parent_pads = g_list_next (parent_pads);
2785 * gst_pad_get_internal_links:
2786 * @pad: the #GstPad to get the internal links of.
2788 * Gets a list of pads to which the given pad is linked to
2789 * inside of the parent element.
2790 * The caller must free this list after use.
2792 * Returns: a newly allocated #GList of pads.
2797 gst_pad_get_internal_links (GstPad * pad)
2801 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2803 if (GST_PAD_INTLINKFUNC (pad))
2804 res = GST_PAD_INTLINKFUNC (pad) (pad);
2811 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
2816 GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
2819 result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
2821 orig = pads = gst_pad_get_internal_links (pad);
2824 GstPad *eventpad = GST_PAD_CAST (pads->data);
2826 pads = g_list_next (pads);
2828 if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
2829 /* for each pad we send to, we should ref the event; it's up
2830 * to downstream to unref again when handled. */
2831 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
2832 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2833 gst_event_ref (event);
2834 gst_pad_push_event (eventpad, event);
2836 /* we only send the event on one pad, multi-sinkpad elements
2837 * should implement a handler */
2838 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
2839 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2840 result = gst_pad_push_event (eventpad, event);
2844 /* we handled the incoming event so we unref once */
2845 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
2846 gst_event_unref (event);
2855 * gst_pad_event_default:
2856 * @pad: a #GstPad to call the default event handler on.
2857 * @event: the #GstEvent to handle.
2859 * Invokes the default event handler for the given pad. End-of-stream and
2860 * discontinuity events are handled specially, and then the event is sent to all
2861 * pads internally linked to @pad. Note that if there are many possible sink
2862 * pads that are internally linked to @pad, only one will be sent an event.
2863 * Multi-sinkpad elements should implement custom event handlers.
2865 * Returns: TRUE if the event was sent succesfully.
2868 gst_pad_event_default (GstPad * pad, GstEvent * event)
2870 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2871 g_return_val_if_fail (event != NULL, FALSE);
2873 switch (GST_EVENT_TYPE (event)) {
2876 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
2877 gst_pad_pause_task (pad);
2883 return gst_pad_event_default_dispatch (pad, event);
2887 * gst_pad_dispatcher:
2888 * @pad: a #GstPad to dispatch.
2889 * @dispatch: the #GstDispatcherFunction to call.
2890 * @data: gpointer user data passed to the dispatcher function.
2892 * Invokes the given dispatcher function on all pads that are
2893 * internally linked to the given pad.
2894 * The GstPadDispatcherFunction should return TRUE when no further pads
2895 * need to be processed.
2897 * Returns: TRUE if one of the dispatcher functions returned TRUE.
2900 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
2903 gboolean res = FALSE;
2904 GList *int_pads, *orig;
2906 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2907 g_return_val_if_fail (dispatch != NULL, FALSE);
2909 orig = int_pads = gst_pad_get_internal_links (pad);
2912 GstPad *int_pad = GST_PAD_CAST (int_pads->data);
2913 GstPad *int_peer = GST_PAD_PEER (int_pad);
2916 res = dispatch (int_peer, data);
2920 int_pads = g_list_next (int_pads);
2930 * @pad: a #GstPad to invoke the default query on.
2931 * @query: the #GstQuery to perform.
2933 * Dispatches a query to a pad. The query should have been allocated by the
2934 * caller via one of the type-specific allocation functions in gstquery.h. The
2935 * element is responsible for filling the query with an appropriate response,
2936 * which should then be parsed with a type-specific query parsing function.
2938 * Again, the caller is responsible for both the allocation and deallocation of
2939 * the query structure.
2941 * Returns: TRUE if the query could be performed.
2944 gst_pad_query (GstPad * pad, GstQuery * query)
2946 GstPadQueryFunction func;
2948 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2949 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2951 GST_DEBUG_OBJECT (pad, "sending query %p", query);
2953 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
2956 return func (pad, query);
2960 GST_DEBUG_OBJECT (pad, "had no query function");
2966 * gst_pad_query_default:
2967 * @pad: a #GstPad to call the default query handler on.
2968 * @query: the #GstQuery to handle.
2970 * Invokes the default query handler for the given pad.
2971 * The query is sent to all pads internally linked to @pad. Note that
2972 * if there are many possible sink pads that are internally linked to
2973 * @pad, only one will be sent the query.
2974 * Multi-sinkpad elements should implement custom query handlers.
2976 * Returns: TRUE if the query was performed succesfully.
2979 gst_pad_query_default (GstPad * pad, GstQuery * query)
2981 switch (GST_QUERY_TYPE (query)) {
2982 case GST_QUERY_POSITION:
2983 case GST_QUERY_SEEKING:
2984 case GST_QUERY_FORMATS:
2985 case GST_QUERY_LATENCY:
2986 case GST_QUERY_JITTER:
2987 case GST_QUERY_RATE:
2988 case GST_QUERY_CONVERT:
2990 return gst_pad_dispatcher
2991 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
2995 #ifndef GST_DISABLE_LOADSAVE
2996 /* FIXME: why isn't this on a GstElement ? */
2998 * gst_pad_load_and_link:
2999 * @self: an #xmlNodePtr to read the description from.
3000 * @parent: the #GstObject element that owns the pad.
3002 * Reads the pad definition from the XML node and links the given pad
3003 * in the element to a pad of an element up in the hierarchy.
3006 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
3008 xmlNodePtr field = self->xmlChildrenNode;
3009 GstPad *pad = NULL, *targetpad;
3013 GstObject *grandparent;
3017 if (!strcmp ((char *) field->name, "name")) {
3018 name = (gchar *) xmlNodeGetContent (field);
3019 pad = gst_element_get_pad (GST_ELEMENT (parent), name);
3021 } else if (!strcmp ((char *) field->name, "peer")) {
3022 peer = (gchar *) xmlNodeGetContent (field);
3024 field = field->next;
3026 g_return_if_fail (pad != NULL);
3031 split = g_strsplit (peer, ".", 2);
3033 if (split[0] == NULL || split[1] == NULL) {
3034 GST_CAT_DEBUG_OBJECT (GST_CAT_XML, pad,
3035 "Could not parse peer '%s', leaving unlinked", peer);
3042 g_return_if_fail (split[0] != NULL);
3043 g_return_if_fail (split[1] != NULL);
3045 grandparent = gst_object_get_parent (parent);
3047 if (grandparent && GST_IS_BIN (grandparent)) {
3048 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
3055 targetpad = gst_element_get_pad (target, split[1]);
3057 if (targetpad == NULL)
3060 gst_pad_link (pad, targetpad);
3067 * gst_pad_save_thyself:
3068 * @pad: a #GstPad to save.
3069 * @parent: the parent #xmlNodePtr to save the description in.
3071 * Saves the pad into an xml representation.
3073 * Returns: the #xmlNodePtr representation of the pad.
3076 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
3081 g_return_val_if_fail (GST_IS_PAD (object), NULL);
3083 pad = GST_PAD (object);
3085 xmlNewChild (parent, NULL, (xmlChar *) "name",
3086 (xmlChar *) GST_PAD_NAME (pad));
3087 if (GST_PAD_PEER (pad) != NULL) {
3090 peer = GST_PAD_PEER (pad);
3091 /* first check to see if the peer's parent's parent is the same */
3092 /* we just save it off */
3093 content = g_strdup_printf ("%s.%s",
3094 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
3095 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
3098 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
3105 * gst_ghost_pad_save_thyself:
3106 * @pad: a ghost #GstPad to save.
3107 * @parent: the parent #xmlNodePtr to save the description in.
3109 * Saves the ghost pad into an xml representation.
3111 * Returns: the #xmlNodePtr representation of the pad.
3114 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
3118 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
3120 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
3121 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
3122 xmlNewChild (self, NULL, (xmlChar *) "parent",
3123 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
3125 /* FIXME FIXME FIXME! */
3130 #endif /* GST_DISABLE_LOADSAVE */
3133 * should be called with pad OBJECT_LOCK and STREAM_LOCK held.
3134 * GST_PAD_IS_BLOCK (pad) == TRUE when this function is
3137 * This function perform the pad blocking when an event, buffer push
3138 * or buffer_alloc is performed on a _SRC_ pad. It blocks the
3139 * streaming thread after informing the pad has been blocked.
3141 * An application can with this method wait and block any streaming
3142 * thread and perform operations such as seeking or linking.
3144 * Two methods are available for notifying the application of the
3146 * - the callback method, which happens in the STREAMING thread with
3147 * the STREAM_LOCK held. With this method, the most usefull way of
3148 * dealing with the callback is to post a message to the main thread
3149 * where the pad block can then be handled outside of the streaming
3150 * thread. With the last method one can perform all operations such
3151 * as doing a state change, linking, unblocking, seeking etc on the
3153 * - the GCond signal method, which makes any thread unblock when
3154 * the pad block happens.
3158 static GstFlowReturn
3159 handle_pad_block (GstPad * pad)
3161 GstPadBlockCallback callback;
3163 GstFlowReturn ret = GST_FLOW_OK;
3165 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
3167 /* flushing, don't bother trying to block and return WRONG_STATE
3169 if (GST_PAD_IS_FLUSHING (pad))
3170 goto flushingnonref;
3172 /* we grab an extra ref for the callbacks, this is probably not
3173 * needed (callback code does not have a ref and cannot unref). I
3174 * think this was done to make it possible to unref the element in
3175 * the callback, which is in the end totally impossible as it
3176 * requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
3177 * all taken when calling this function. */
3178 gst_object_ref (pad);
3180 /* we either have a callback installed to notify the block or
3181 * some other thread is doing a GCond wait. */
3182 callback = pad->block_callback;
3184 /* there is a callback installed, call it. We release the
3185 * lock so that the callback can do something usefull with the
3187 user_data = pad->block_data;
3188 GST_OBJECT_UNLOCK (pad);
3189 callback (pad, TRUE, user_data);
3190 GST_OBJECT_LOCK (pad);
3192 /* no callback, signal the thread that is doing a GCond wait
3194 GST_PAD_BLOCK_SIGNAL (pad);
3197 /* OBJECT_LOCK could have been released when we did the callback, which
3198 * then could have made the pad unblock so we need to check the blocking
3199 * condition again. */
3200 while (GST_PAD_IS_BLOCKED (pad)) {
3201 if (GST_PAD_IS_FLUSHING (pad))
3204 /* now we block the streaming thread. It can be unlocked when we
3205 * deactivate the pad (which will also set the FLUSHING flag) or
3206 * when the pad is unblocked. A flushing event will also unblock
3207 * the pad after setting the FLUSHING flag. */
3208 GST_PAD_BLOCK_WAIT (pad);
3210 /* see if we got unlocked by a flush or not */
3211 if (GST_PAD_IS_FLUSHING (pad))
3215 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
3217 /* when we get here, the pad is unblocked again and we perform
3218 * the needed unblock code. */
3219 callback = pad->block_callback;
3221 /* we need to call the callback */
3222 user_data = pad->block_data;
3223 GST_OBJECT_UNLOCK (pad);
3224 callback (pad, FALSE, user_data);
3225 GST_OBJECT_LOCK (pad);
3227 /* we need to signal the thread waiting on the GCond */
3228 GST_PAD_BLOCK_SIGNAL (pad);
3231 gst_object_unref (pad);
3237 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
3238 return GST_FLOW_WRONG_STATE;
3242 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
3243 gst_object_unref (pad);
3244 return GST_FLOW_WRONG_STATE;
3248 /**********************************************************************
3249 * Data passing functions
3253 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
3256 GValue args[2] = { {0}, {0} };
3261 g_value_init (&ret, G_TYPE_BOOLEAN);
3262 g_value_set_boolean (&ret, TRUE);
3263 g_value_init (&args[0], GST_TYPE_PAD);
3264 g_value_set_object (&args[0], pad);
3265 g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
3266 gst_value_set_mini_object (&args[1], obj);
3268 if (GST_IS_EVENT (obj))
3269 detail = event_quark;
3271 detail = buffer_quark;
3274 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
3275 res = g_value_get_boolean (&ret);
3278 g_value_unset (&ret);
3279 g_value_unset (&args[0]);
3280 g_value_unset (&args[1]);
3285 /* this is the chain function that does not perform the additional argument
3286 * checking for that little extra speed.
3288 static inline GstFlowReturn
3289 gst_pad_chain_unchecked (GstPad * pad, GstBuffer * buffer)
3292 gboolean caps_changed;
3293 GstPadChainFunction chainfunc;
3295 gboolean emit_signal;
3297 GST_PAD_STREAM_LOCK (pad);
3299 GST_OBJECT_LOCK (pad);
3300 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3303 caps = GST_BUFFER_CAPS (buffer);
3304 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3306 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3307 GST_OBJECT_UNLOCK (pad);
3309 /* see if the signal should be emited, we emit before caps nego as
3310 * we might drop the buffer and do capsnego for nothing. */
3311 if (G_UNLIKELY (emit_signal)) {
3312 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3316 /* we got a new datatype on the pad, see if it can handle it */
3317 if (G_UNLIKELY (caps_changed)) {
3318 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3319 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
3320 goto not_negotiated;
3323 /* NOTE: we read the chainfunc unlocked.
3324 * we cannot hold the lock for the pad so we might send
3325 * the data to the wrong function. This is not really a
3326 * problem since functions are assigned at creation time
3327 * and don't change that often... */
3328 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
3331 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3332 "calling chainfunction &%s", GST_DEBUG_FUNCPTR_NAME (chainfunc));
3334 ret = chainfunc (pad, buffer);
3336 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3337 "called chainfunction &%s, returned %s",
3338 GST_DEBUG_FUNCPTR_NAME (chainfunc), gst_flow_get_name (ret));
3340 GST_PAD_STREAM_UNLOCK (pad);
3347 gst_buffer_unref (buffer);
3348 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3349 "pushing, but pad was flushing");
3350 GST_OBJECT_UNLOCK (pad);
3351 GST_PAD_STREAM_UNLOCK (pad);
3352 return GST_FLOW_WRONG_STATE;
3356 gst_buffer_unref (buffer);
3357 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3358 GST_PAD_STREAM_UNLOCK (pad);
3363 gst_buffer_unref (buffer);
3364 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3365 "pushing buffer but pad did not accept");
3366 GST_PAD_STREAM_UNLOCK (pad);
3367 return GST_FLOW_NOT_NEGOTIATED;
3371 gst_buffer_unref (buffer);
3372 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3373 "pushing, but not chainhandler");
3374 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3375 ("push on pad %s:%s but it has no chainfunction",
3376 GST_DEBUG_PAD_NAME (pad)));
3377 GST_PAD_STREAM_UNLOCK (pad);
3378 return GST_FLOW_NOT_SUPPORTED;
3384 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3385 * @buffer: the #GstBuffer to send, return GST_FLOW_ERROR if not.
3387 * Chain a buffer to @pad.
3389 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
3391 * If the caps on @buffer are different from the current caps on @pad, this
3392 * function will call any setcaps function (see gst_pad_set_setcaps_function())
3393 * installed on @pad. If the new caps are not acceptable for @pad, this function
3394 * returns #GST_FLOW_NOT_NEGOTIATED.
3396 * The function proceeds calling the chain function installed on @pad (see
3397 * gst_pad_set_chain_function()) and the return value of that function is
3398 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
3401 * In all cases, success or failure, the caller loses its reference to @buffer
3402 * after calling this function.
3404 * Returns: a #GstFlowReturn from the pad.
3409 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
3411 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3412 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3414 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3416 return gst_pad_chain_unchecked (pad, buffer);
3421 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
3422 * @buffer: the #GstBuffer to push returns GST_FLOW_ERROR if not.
3424 * Pushes a buffer to the peer of @pad.
3426 * This function will call an installed pad block before triggering any
3427 * installed pad probes.
3429 * If the caps on @buffer are different from the currently configured caps on
3430 * @pad, this function will call any installed setcaps function on @pad (see
3431 * gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
3432 * format, this function returns #GST_FLOW_NOT_NEGOTIATED.
3434 * The function proceeds calling gst_pad_chain() on the peer pad and returns the
3435 * value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will be
3438 * In all cases, success or failure, the caller loses its reference to @buffer
3439 * after calling this function.
3441 * Returns: a #GstFlowReturn from the peer pad.
3446 gst_pad_push (GstPad * pad, GstBuffer * buffer)
3452 gboolean caps_changed;
3454 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3455 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3456 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3458 GST_OBJECT_LOCK (pad);
3460 /* FIXME: this check can go away; pad_set_blocked could be implemented with
3461 * probes completely or probes with an extended pad block. */
3462 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3463 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
3466 /* we emit signals on the pad arg, the peer will have a chance to
3467 * emit in the _chain() function */
3468 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
3469 /* unlock before emitting */
3470 GST_OBJECT_UNLOCK (pad);
3472 /* if the signal handler returned FALSE, it means we should just drop the
3474 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3477 GST_OBJECT_LOCK (pad);
3480 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3483 /* take ref to peer pad before releasing the lock */
3484 gst_object_ref (peer);
3486 /* Before pushing the buffer to the peer pad, ensure that caps
3487 * are set on this pad */
3488 caps = GST_BUFFER_CAPS (buffer);
3489 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3491 GST_OBJECT_UNLOCK (pad);
3493 /* we got a new datatype from the pad, it had better handle it */
3494 if (G_UNLIKELY (caps_changed)) {
3495 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3496 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
3497 goto not_negotiated;
3500 ret = gst_pad_chain_unchecked (peer, buffer);
3502 gst_object_unref (peer);
3506 /* ERROR recovery here */
3509 gst_buffer_unref (buffer);
3510 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
3511 GST_OBJECT_UNLOCK (pad);
3516 gst_buffer_unref (buffer);
3517 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3522 gst_buffer_unref (buffer);
3523 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3524 "pushing, but it was not linked");
3525 GST_OBJECT_UNLOCK (pad);
3526 return GST_FLOW_NOT_LINKED;
3530 gst_buffer_unref (buffer);
3531 gst_object_unref (peer);
3532 GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
3533 "element pushed buffer then refused to accept the caps");
3534 return GST_FLOW_NOT_NEGOTIATED;
3539 * gst_pad_check_pull_range:
3540 * @pad: a sink #GstPad.
3542 * Checks if a gst_pad_pull_range() can be performed on the peer
3543 * source pad. This function is used by plugins that want to check
3544 * if they can use random access on the peer source pad.
3546 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
3547 * if it needs to perform some logic to determine if pull_range is
3550 * Returns: a gboolean with the result.
3555 gst_pad_check_pull_range (GstPad * pad)
3559 GstPadCheckGetRangeFunction checkgetrangefunc;
3561 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3563 GST_OBJECT_LOCK (pad);
3564 if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
3565 goto wrong_direction;
3567 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3570 gst_object_ref (peer);
3571 GST_OBJECT_UNLOCK (pad);
3573 /* see note in above function */
3574 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
3575 /* FIXME, kindoff ghetto */
3576 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
3578 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3579 "calling checkgetrangefunc %s of peer pad %s:%s",
3580 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
3582 ret = checkgetrangefunc (peer);
3585 gst_object_unref (peer);
3589 /* ERROR recovery here */
3592 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3593 "checking pull range, but pad must be a sinkpad");
3594 GST_OBJECT_UNLOCK (pad);
3599 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3600 "checking pull range, but it was not linked");
3601 GST_OBJECT_UNLOCK (pad);
3607 * gst_pad_get_range:
3608 * @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
3609 * @offset: The start offset of the buffer
3610 * @size: The length of the buffer
3611 * @buffer: a pointer to hold the #GstBuffer, returns #GST_FLOW_ERROR if %NULL.
3613 * When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
3616 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
3617 * description of a getrange function. If @pad has no getrange function
3618 * installed (see gst_pad_set_getrange_function()) this function returns
3619 * #GST_FLOW_NOT_SUPPORTED.
3621 * Returns: a #GstFlowReturn from the pad.
3626 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
3627 GstBuffer ** buffer)
3630 GstPadGetRangeFunction getrangefunc;
3631 gboolean emit_signal;
3633 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3634 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3635 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3637 GST_PAD_STREAM_LOCK (pad);
3639 GST_OBJECT_LOCK (pad);
3640 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3643 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3644 GST_OBJECT_UNLOCK (pad);
3646 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
3649 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3650 "calling getrangefunc %s, offset %"
3651 G_GUINT64_FORMAT ", size %u",
3652 GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
3654 ret = getrangefunc (pad, offset, size, buffer);
3656 /* can only fire the signal if we have a valid buffer */
3657 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3658 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3662 GST_PAD_STREAM_UNLOCK (pad);
3669 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3670 "pulling range, but pad was flushing");
3671 GST_OBJECT_UNLOCK (pad);
3672 GST_PAD_STREAM_UNLOCK (pad);
3673 return GST_FLOW_WRONG_STATE;
3677 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3678 ("pullrange on pad %s:%s but it has no getrangefunction",
3679 GST_DEBUG_PAD_NAME (pad)));
3680 GST_PAD_STREAM_UNLOCK (pad);
3681 return GST_FLOW_NOT_SUPPORTED;
3685 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3686 "Dropping data after FALSE probe return");
3687 GST_PAD_STREAM_UNLOCK (pad);
3688 gst_buffer_unref (*buffer);
3690 return GST_FLOW_UNEXPECTED;
3696 * gst_pad_pull_range:
3697 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3698 * @offset: The start offset of the buffer
3699 * @size: The length of the buffer
3700 * @buffer: a pointer to hold the #GstBuffer, returns GST_FLOW_ERROR if %NULL.
3702 * Pulls a buffer from the peer pad.
3704 * This function will first trigger the pad block signal if it was
3707 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
3708 * function returns the result of gst_pad_get_range() on the peer pad.
3709 * See gst_pad_get_range() for a list of return values and for the
3710 * semantics of the arguments of this function.
3712 * Returns: a #GstFlowReturn from the peer pad.
3713 * When this function returns #GST_FLOW_OK, @buffer will contain a valid
3714 * #GstBuffer that should be freed with gst_buffer_unref() after usage.
3715 * @buffer may not be used or freed when any other return value than
3716 * #GST_FLOW_OK is returned.
3721 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
3722 GstBuffer ** buffer)
3726 gboolean emit_signal;
3728 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3729 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3731 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3733 GST_OBJECT_LOCK (pad);
3735 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3736 handle_pad_block (pad);
3738 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3741 /* signal emision for the pad, peer has chance to emit when
3742 * we call _get_range() */
3743 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3745 gst_object_ref (peer);
3746 GST_OBJECT_UNLOCK (pad);
3748 ret = gst_pad_get_range (peer, offset, size, buffer);
3750 gst_object_unref (peer);
3752 /* can only fire the signal if we have a valid buffer */
3753 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3754 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3759 /* ERROR recovery here */
3762 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3763 "pulling range, but it was not linked");
3764 GST_OBJECT_UNLOCK (pad);
3765 return GST_FLOW_NOT_LINKED;
3769 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3770 "Dropping data after FALSE probe return");
3771 gst_buffer_unref (*buffer);
3773 return GST_FLOW_UNEXPECTED;
3778 * gst_pad_push_event:
3779 * @pad: a #GstPad to push the event to.
3780 * @event: the #GstEvent to send to the pad.
3782 * Sends the event to the peer of the given pad. This function is
3783 * mainly used by elements to send events to their peer
3786 * This function takes owership of the provided event so you should
3787 * gst_event_ref() it if you want to reuse the event after this call.
3789 * Returns: TRUE if the event was handled.
3794 gst_pad_push_event (GstPad * pad, GstEvent * event)
3799 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3800 g_return_val_if_fail (event != NULL, FALSE);
3801 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
3803 GST_LOG_OBJECT (pad, "event:%s", GST_EVENT_TYPE_NAME (event));
3805 GST_OBJECT_LOCK (pad);
3807 /* Two checks to be made:
3808 * . (un)set the FLUSHING flag for flushing events,
3809 * . handle pad blocking */
3810 switch (GST_EVENT_TYPE (event)) {
3811 case GST_EVENT_FLUSH_START:
3812 GST_PAD_SET_FLUSHING (pad);
3814 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3815 /* flush start will have set the FLUSHING flag and will then
3816 * unlock all threads doing a GCond wait on the blocked pad. This
3817 * will typically unblock the STREAMING thread blocked on a pad. */
3818 GST_PAD_BLOCK_SIGNAL (pad);
3822 case GST_EVENT_FLUSH_STOP:
3823 GST_PAD_UNSET_FLUSHING (pad);
3825 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3829 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3830 if (GST_PAD_IS_FLUSHING (pad))
3832 while (GST_PAD_IS_BLOCKED (pad))
3833 /* else block the event as long as the pad is blocked */
3834 if (handle_pad_block (pad) != GST_FLOW_OK)
3840 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3841 GST_OBJECT_UNLOCK (pad);
3843 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3846 GST_OBJECT_LOCK (pad);
3848 peerpad = GST_PAD_PEER (pad);
3849 if (peerpad == NULL)
3852 GST_LOG_OBJECT (peerpad, "sending event on peerpad");
3853 gst_object_ref (peerpad);
3854 GST_OBJECT_UNLOCK (pad);
3856 result = gst_pad_send_event (peerpad, event);
3858 gst_object_unref (peerpad);
3859 GST_LOG_OBJECT (peerpad, "sent event on peerpad");
3863 /* ERROR handling */
3866 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
3867 gst_event_unref (event);
3872 GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
3873 gst_event_unref (event);
3874 GST_OBJECT_UNLOCK (pad);
3880 GST_DEBUG_OBJECT (pad,
3881 "Not forwarding event since we're flushing and blocking");
3882 gst_event_unref (event);
3883 GST_OBJECT_UNLOCK (pad);
3889 * gst_pad_send_event:
3890 * @pad: a #GstPad to send the event to.
3891 * @event: the #GstEvent to send to the pad.
3893 * Sends the event to the pad. This function can be used
3894 * by applications to send events in the pipeline.
3896 * If @pad is a source pad, @event should be an upstream event. If @pad is a
3897 * sink pad, @event should be a downstream event. For example, you would not
3898 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
3899 * Furthermore, some downstream events have to be serialized with data flow,
3900 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
3901 * the event needs to be serialized with data flow, this function will take the
3902 * pad's stream lock while calling its event function.
3904 * To find out whether an event type is upstream, downstream, or downstream and
3905 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
3906 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
3907 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or plugin
3908 * doesn't need to bother itself with this information; the core handles all
3909 * necessary locks and checks.
3911 * This function takes owership of the provided event so you should
3912 * gst_event_ref() it if you want to reuse the event after this call.
3914 * Returns: TRUE if the event was handled.
3917 gst_pad_send_event (GstPad * pad, GstEvent * event)
3919 gboolean result = FALSE;
3920 GstPadEventFunction eventfunc;
3921 gboolean serialized, need_unlock = FALSE;
3923 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3924 g_return_val_if_fail (event != NULL, FALSE);
3926 GST_OBJECT_LOCK (pad);
3927 if (GST_PAD_IS_SINK (pad)) {
3928 if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
3929 goto wrong_direction;
3930 serialized = GST_EVENT_IS_SERIALIZED (event);
3931 } else if (GST_PAD_IS_SRC (pad)) {
3932 if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
3933 goto wrong_direction;
3934 /* events on srcpad never are serialized */
3937 goto unknown_direction;
3939 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
3940 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
3941 GST_EVENT_SRC (event) = gst_object_ref (pad);
3945 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3946 GST_OBJECT_UNLOCK (pad);
3948 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
3951 GST_OBJECT_LOCK (pad);
3954 switch (GST_EVENT_TYPE (event)) {
3955 case GST_EVENT_FLUSH_START:
3956 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
3957 "have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
3959 /* can't even accept a flush begin event when flushing */
3960 if (GST_PAD_IS_FLUSHING (pad))
3962 GST_PAD_SET_FLUSHING (pad);
3963 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
3965 case GST_EVENT_FLUSH_STOP:
3966 GST_PAD_UNSET_FLUSHING (pad);
3967 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
3968 GST_OBJECT_UNLOCK (pad);
3969 /* grab stream lock */
3970 GST_PAD_STREAM_LOCK (pad);
3972 GST_OBJECT_LOCK (pad);
3975 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
3976 GST_EVENT_TYPE_NAME (event));
3978 /* make this a little faster, no point in grabbing the lock
3979 * if the pad is allready flushing. */
3980 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3984 /* lock order: STREAM_LOCK, LOCK */
3985 GST_OBJECT_UNLOCK (pad);
3986 GST_PAD_STREAM_LOCK (pad);
3988 GST_OBJECT_LOCK (pad);
3989 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3994 if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
3997 GST_OBJECT_UNLOCK (pad);
3999 result = eventfunc (pad, event);
4002 GST_PAD_STREAM_UNLOCK (pad);
4006 /* ERROR handling */
4009 g_warning ("pad %s:%s sending %s event in wrong direction",
4010 GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
4011 GST_OBJECT_UNLOCK (pad);
4012 gst_event_unref (event);
4017 g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
4018 GST_OBJECT_UNLOCK (pad);
4019 gst_event_unref (event);
4024 g_warning ("pad %s:%s has no event handler, file a bug.",
4025 GST_DEBUG_PAD_NAME (pad));
4026 GST_OBJECT_UNLOCK (pad);
4027 gst_event_unref (event);
4032 GST_OBJECT_UNLOCK (pad);
4034 GST_PAD_STREAM_UNLOCK (pad);
4035 GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
4036 "Received event on flushing pad. Discarding");
4037 gst_event_unref (event);
4042 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
4043 gst_event_unref (event);
4049 * gst_pad_set_element_private:
4050 * @pad: the #GstPad to set the private data of.
4051 * @priv: The private data to attach to the pad.
4053 * Set the given private data gpointer on the pad.
4054 * This function can only be used by the element that owns the pad.
4055 * No locking is performed in this function.
4058 gst_pad_set_element_private (GstPad * pad, gpointer priv)
4060 pad->element_private = priv;
4064 * gst_pad_get_element_private:
4065 * @pad: the #GstPad to get the private data of.
4067 * Gets the private data of a pad.
4068 * No locking is performed in this function.
4070 * Returns: a #gpointer to the private data.
4073 gst_pad_get_element_private (GstPad * pad)
4075 return pad->element_private;
4079 * gst_pad_start_task:
4080 * @pad: the #GstPad to start the task of
4081 * @func: the task function to call
4082 * @data: data passed to the task function
4084 * Starts a task that repeadedly calls @func with @data. This function
4085 * is nostly used in the pad activation function to start the
4086 * dataflow. This function will automatically acquire the STREAM_LOCK of
4087 * the pad before calling @func.
4089 * Returns: a TRUE if the task could be started.
4092 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
4096 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4097 g_return_val_if_fail (func != NULL, FALSE);
4099 GST_OBJECT_LOCK (pad);
4100 task = GST_PAD_TASK (pad);
4102 task = gst_task_create (func, data);
4103 gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
4104 GST_PAD_TASK (pad) = task;
4106 gst_task_start (task);
4107 GST_OBJECT_UNLOCK (pad);
4113 * gst_pad_pause_task:
4114 * @pad: the #GstPad to pause the task of
4116 * Pause the task of @pad. This function will also make sure that the
4117 * function executed by the task will effectively stop.
4119 * Returns: a TRUE if the task could be paused or FALSE when the pad
4123 gst_pad_pause_task (GstPad * pad)
4127 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4129 GST_OBJECT_LOCK (pad);
4130 task = GST_PAD_TASK (pad);
4133 gst_task_pause (task);
4134 GST_OBJECT_UNLOCK (pad);
4136 GST_PAD_STREAM_LOCK (pad);
4137 GST_PAD_STREAM_UNLOCK (pad);
4143 GST_DEBUG_OBJECT (pad, "pad has no task");
4144 GST_OBJECT_UNLOCK (pad);
4150 * gst_pad_stop_task:
4151 * @pad: the #GstPad to stop the task of
4153 * Stop the task of @pad. This function will also make sure that the
4154 * function executed by the task will effectively stop if not called
4155 * from the GstTaskFunction.
4157 * This function will deadlock if called from the GstTaskFunction of
4158 * the task. Use gst_task_pause() instead.
4160 * Regardless of whether the pad has a task, the stream lock is acquired and
4161 * released so as to ensure that streaming through this pad has finished.
4163 * Returns: a TRUE if the task could be stopped or FALSE on error.
4166 gst_pad_stop_task (GstPad * pad)
4170 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4172 GST_OBJECT_LOCK (pad);
4173 task = GST_PAD_TASK (pad);
4176 GST_PAD_TASK (pad) = NULL;
4177 gst_task_stop (task);
4178 GST_OBJECT_UNLOCK (pad);
4180 GST_PAD_STREAM_LOCK (pad);
4181 GST_PAD_STREAM_UNLOCK (pad);
4183 gst_task_join (task);
4185 gst_object_unref (task);
4191 GST_OBJECT_UNLOCK (pad);
4193 GST_PAD_STREAM_LOCK (pad);
4194 GST_PAD_STREAM_UNLOCK (pad);