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:
666 GST_OBJECT_LOCK (pad);
668 g_critical ("Failed to deactivate pad %s:%s, very bad",
669 GST_DEBUG_PAD_NAME (pad));
671 GST_WARNING ("Failed to activate pad %s:%s", GST_DEBUG_PAD_NAME (pad));
673 GST_OBJECT_UNLOCK (pad);
680 * gst_pad_activate_pull:
681 * @pad: the #GstPad to activate or deactivate.
682 * @active: whether or not the pad should be active.
684 * Activates or deactivates the given pad in pull mode via dispatching to the
685 * pad's activatepullfunc. For use from within pad activation functions only.
686 * When called on sink pads, will first proxy the call to the peer pad, which is
687 * expected to activate its internally linked pads from within its activate_pull
690 * If you don't know what this is, you probably don't want to call it.
692 * Returns: TRUE if the operation was successful.
697 gst_pad_activate_pull (GstPad * pad, gboolean active)
699 GstActivateMode old, new;
702 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
704 GST_OBJECT_LOCK (pad);
705 old = GST_PAD_ACTIVATE_MODE (pad);
706 GST_OBJECT_UNLOCK (pad);
710 case GST_ACTIVATE_PULL:
712 case GST_ACTIVATE_PUSH:
713 /* pad was activate in the wrong direction, deactivate it
714 * and reactivate it in pull mode */
715 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
716 goto deactivate_failed;
717 /* fallthrough, pad is deactivated now. */
718 case GST_ACTIVATE_NONE:
723 case GST_ACTIVATE_NONE:
725 case GST_ACTIVATE_PUSH:
726 /* pad was activated in the other direction, deactivate it
727 * in push mode, this should not happen... */
728 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
729 goto deactivate_failed;
730 /* everything is fine now */
732 case GST_ACTIVATE_PULL:
737 if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
738 if ((peer = gst_pad_get_peer (pad))) {
739 if (G_UNLIKELY (!gst_pad_activate_pull (peer, active)))
741 gst_object_unref (peer);
744 if (G_UNLIKELY (GST_PAD_GETRANGEFUNC (pad) == NULL))
745 goto failure; /* Can't activate pull on a src without a
749 new = active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
750 pre_activate (pad, new);
752 if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
753 if (G_UNLIKELY (!GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active)))
756 /* can happen for sinks of passthrough elements */
759 post_activate (pad, new);
761 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
762 active ? "activated" : "deactivated");
768 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
769 active ? "activated" : "deactivated");
774 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
775 "failed to %s in switch to pull from mode %d",
776 (active ? "activate" : "deactivate"), old);
781 GST_OBJECT_LOCK (peer);
782 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
783 "activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
784 GST_OBJECT_UNLOCK (peer);
785 gst_object_unref (peer);
790 GST_OBJECT_LOCK (pad);
791 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
792 active ? "activate" : "deactivate");
793 GST_PAD_SET_FLUSHING (pad);
794 GST_PAD_ACTIVATE_MODE (pad) = old;
795 GST_OBJECT_UNLOCK (pad);
801 * gst_pad_activate_push:
802 * @pad: the #GstPad to activate or deactivate.
803 * @active: whether the pad should be active or not.
805 * Activates or deactivates the given pad in push mode via dispatching to the
806 * pad's activatepushfunc. For use from within pad activation functions only.
808 * If you don't know what this is, you probably don't want to call it.
810 * Returns: %TRUE if the operation was successful.
815 gst_pad_activate_push (GstPad * pad, gboolean active)
817 GstActivateMode old, new;
819 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
820 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
821 active ? "activated" : "deactivated");
823 GST_OBJECT_LOCK (pad);
824 old = GST_PAD_ACTIVATE_MODE (pad);
825 GST_OBJECT_UNLOCK (pad);
829 case GST_ACTIVATE_PUSH:
831 case GST_ACTIVATE_PULL:
832 /* pad was activate in the wrong direction, deactivate it
833 * an reactivate it in push mode */
834 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
835 goto deactivate_failed;
836 /* fallthrough, pad is deactivated now. */
837 case GST_ACTIVATE_NONE:
842 case GST_ACTIVATE_NONE:
844 case GST_ACTIVATE_PULL:
845 /* pad was activated in the other direction, deactivate it
846 * in pull mode, this should not happen... */
847 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
848 goto deactivate_failed;
849 /* everything is fine now */
851 case GST_ACTIVATE_PUSH:
856 new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
857 pre_activate (pad, new);
859 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
860 if (G_UNLIKELY (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active))) {
864 /* quite ok, element relies on state change func to prepare itself */
867 post_activate (pad, new);
869 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
870 active ? "activated" : "deactivated");
875 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
876 active ? "activated" : "deactivated");
881 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
882 "failed to %s in switch to push from mode %d",
883 (active ? "activate" : "deactivate"), old);
888 GST_OBJECT_LOCK (pad);
889 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
890 active ? "activate" : "deactivate");
891 GST_PAD_SET_FLUSHING (pad);
892 GST_PAD_ACTIVATE_MODE (pad) = old;
893 GST_OBJECT_UNLOCK (pad);
900 * @pad: the #GstPad to query
902 * Query if a pad is active
904 * Returns: TRUE if the pad is active.
909 gst_pad_is_active (GstPad * pad)
911 gboolean result = FALSE;
913 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
915 GST_OBJECT_LOCK (pad);
916 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
917 GST_OBJECT_UNLOCK (pad);
923 * gst_pad_set_blocked_async:
924 * @pad: the #GstPad to block or unblock
925 * @blocked: boolean indicating whether the pad should be blocked or unblocked
926 * @callback: #GstPadBlockCallback that will be called when the
928 * @user_data: user data passed to the callback
930 * Blocks or unblocks the dataflow on a pad. The provided callback
931 * is called when the operation succeeds; this happens right before the next
932 * attempt at pushing a buffer on the pad.
934 * This can take a while as the pad can only become blocked when real dataflow
936 * When the pipeline is stalled, for example in PAUSED, this can
937 * take an indeterminate amount of time.
938 * You can pass NULL as the callback to make this call block. Be careful with
939 * this blocking call as it might not return for reasons stated above.
941 * Returns: TRUE if the pad could be blocked. This function can fail
942 * if wrong parameters were passed or the pad was already in the
948 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
949 GstPadBlockCallback callback, gpointer user_data)
951 gboolean was_blocked = FALSE;
953 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
955 GST_OBJECT_LOCK (pad);
957 was_blocked = GST_PAD_IS_BLOCKED (pad);
959 if (G_UNLIKELY (was_blocked == blocked))
960 goto had_right_state;
963 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
965 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
966 pad->block_callback = callback;
967 pad->block_data = user_data;
969 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
970 GST_PAD_BLOCK_WAIT (pad);
971 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
974 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
976 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
978 pad->block_callback = callback;
979 pad->block_data = user_data;
982 GST_PAD_BLOCK_SIGNAL (pad);
984 GST_PAD_BLOCK_SIGNAL (pad);
985 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
986 GST_PAD_BLOCK_WAIT (pad);
987 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
990 GST_OBJECT_UNLOCK (pad);
996 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
997 "pad was in right state (%d)", was_blocked);
998 GST_OBJECT_UNLOCK (pad);
1005 * gst_pad_set_blocked:
1006 * @pad: the #GstPad to block or unblock
1007 * @blocked: boolean indicating we should block or unblock
1009 * Blocks or unblocks the dataflow on a pad. This function is
1010 * a shortcut for gst_pad_set_blocked_async() with a NULL
1013 * Returns: TRUE if the pad could be blocked. This function can fail
1014 * wrong parameters were passed or the pad was already in the
1020 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
1022 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
1026 * gst_pad_is_blocked:
1027 * @pad: the #GstPad to query
1029 * Checks if the pad is blocked or not. This function returns the
1030 * last requested state of the pad. It is not certain that the pad
1031 * is actually blocked at this point.
1033 * Returns: TRUE if the pad is blocked.
1038 gst_pad_is_blocked (GstPad * pad)
1040 gboolean result = FALSE;
1042 g_return_val_if_fail (GST_IS_PAD (pad), result);
1044 GST_OBJECT_LOCK (pad);
1045 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
1046 GST_OBJECT_UNLOCK (pad);
1052 * gst_pad_set_activate_function:
1054 * @activate: the #GstPadActivateFunction to set.
1056 * Sets the given activate function for @pad. The activate function will
1057 * dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
1058 * the actual activation. Only makes sense to set on sink pads.
1060 * Call this function if your sink pad can start a pull-based task.
1063 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
1065 g_return_if_fail (GST_IS_PAD (pad));
1067 GST_PAD_ACTIVATEFUNC (pad) = activate;
1068 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
1069 GST_DEBUG_FUNCPTR_NAME (activate));
1073 * gst_pad_set_activatepull_function:
1075 * @activatepull: the #GstPadActivateModeFunction to set.
1077 * Sets the given activate_pull function for the pad. An activate_pull function
1078 * prepares the element and any upstream connections for pulling. See XXX
1079 * part-activation.txt for details.
1082 gst_pad_set_activatepull_function (GstPad * pad,
1083 GstPadActivateModeFunction activatepull)
1085 g_return_if_fail (GST_IS_PAD (pad));
1087 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
1088 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
1089 GST_DEBUG_FUNCPTR_NAME (activatepull));
1093 * gst_pad_set_activatepush_function:
1095 * @activatepush: the #GstPadActivateModeFunction to set.
1097 * Sets the given activate_push function for the pad. An activate_push function
1098 * prepares the element for pushing. See XXX part-activation.txt for details.
1101 gst_pad_set_activatepush_function (GstPad * pad,
1102 GstPadActivateModeFunction activatepush)
1104 g_return_if_fail (GST_IS_PAD (pad));
1106 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1107 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
1108 GST_DEBUG_FUNCPTR_NAME (activatepush));
1112 * gst_pad_set_chain_function:
1113 * @pad: a sink #GstPad.
1114 * @chain: the #GstPadChainFunction to set.
1116 * Sets the given chain function for the pad. The chain function is called to
1117 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1120 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1122 g_return_if_fail (GST_IS_PAD (pad));
1123 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
1125 GST_PAD_CHAINFUNC (pad) = chain;
1126 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
1127 GST_DEBUG_FUNCPTR_NAME (chain));
1131 * gst_pad_set_getrange_function:
1132 * @pad: a source #GstPad.
1133 * @get: the #GstPadGetRangeFunction to set.
1135 * Sets the given getrange function for the pad. The getrange function is called to
1136 * produce a new #GstBuffer to start the processing pipeline. see
1137 * #GstPadGetRangeFunction for a description of the getrange function.
1140 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1142 g_return_if_fail (GST_IS_PAD (pad));
1143 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1145 GST_PAD_GETRANGEFUNC (pad) = get;
1147 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
1148 GST_DEBUG_FUNCPTR_NAME (get));
1152 * gst_pad_set_checkgetrange_function:
1153 * @pad: a source #GstPad.
1154 * @check: the #GstPadCheckGetRangeFunction to set.
1156 * Sets the given checkgetrange function for the pad. Implement this function on
1157 * a pad if you dynamically support getrange based scheduling on the pad.
1160 gst_pad_set_checkgetrange_function (GstPad * pad,
1161 GstPadCheckGetRangeFunction check)
1163 g_return_if_fail (GST_IS_PAD (pad));
1164 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1166 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1168 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
1169 GST_DEBUG_FUNCPTR_NAME (check));
1173 * gst_pad_set_event_function:
1174 * @pad: a source #GstPad.
1175 * @event: the #GstPadEventFunction to set.
1177 * Sets the given event handler for the pad.
1180 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1182 g_return_if_fail (GST_IS_PAD (pad));
1184 GST_PAD_EVENTFUNC (pad) = event;
1186 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
1187 GST_DEBUG_FUNCPTR_NAME (event));
1191 * gst_pad_set_query_function:
1192 * @pad: a #GstPad of either direction.
1193 * @query: the #GstPadQueryFunction to set.
1195 * Set the given query function for the pad.
1198 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1200 g_return_if_fail (GST_IS_PAD (pad));
1202 GST_PAD_QUERYFUNC (pad) = query;
1204 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
1205 GST_DEBUG_FUNCPTR_NAME (query));
1209 * gst_pad_set_query_type_function:
1210 * @pad: a #GstPad of either direction.
1211 * @type_func: the #GstPadQueryTypeFunction to set.
1213 * Set the given query type function for the pad.
1216 gst_pad_set_query_type_function (GstPad * pad,
1217 GstPadQueryTypeFunction type_func)
1219 g_return_if_fail (GST_IS_PAD (pad));
1221 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1223 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
1224 GST_DEBUG_FUNCPTR_NAME (type_func));
1228 * gst_pad_get_query_types:
1231 * Get an array of supported queries that can be performed
1234 * Returns: a zero-terminated array of #GstQueryType.
1236 const GstQueryType *
1237 gst_pad_get_query_types (GstPad * pad)
1239 GstPadQueryTypeFunction func;
1241 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1243 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1255 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1257 *data = gst_pad_get_query_types (pad);
1263 * gst_pad_get_query_types_default:
1266 * Invoke the default dispatcher for the query types on
1269 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1270 * internally-linked pads has a query types function.
1272 const GstQueryType *
1273 gst_pad_get_query_types_default (GstPad * pad)
1275 GstQueryType *result = NULL;
1277 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1279 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1280 gst_pad_get_query_types_dispatcher, &result);
1286 * gst_pad_set_internal_link_function:
1287 * @pad: a #GstPad of either direction.
1288 * @intlink: the #GstPadIntLinkFunction to set.
1290 * Sets the given internal link function for the pad.
1293 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1295 g_return_if_fail (GST_IS_PAD (pad));
1297 GST_PAD_INTLINKFUNC (pad) = intlink;
1298 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
1299 GST_DEBUG_FUNCPTR_NAME (intlink));
1303 * gst_pad_set_link_function:
1305 * @link: the #GstPadLinkFunction to set.
1307 * Sets the given link function for the pad. It will be called when
1308 * the pad is linked with another pad.
1310 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1313 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1314 * cannot be made for some reason.
1316 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1317 * of the peer sink pad, if present.
1320 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1322 g_return_if_fail (GST_IS_PAD (pad));
1324 GST_PAD_LINKFUNC (pad) = link;
1325 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
1326 GST_DEBUG_FUNCPTR_NAME (link));
1330 * gst_pad_set_unlink_function:
1332 * @unlink: the #GstPadUnlinkFunction to set.
1334 * Sets the given unlink function for the pad. It will be called
1335 * when the pad is unlinked.
1338 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1340 g_return_if_fail (GST_IS_PAD (pad));
1342 GST_PAD_UNLINKFUNC (pad) = unlink;
1343 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
1344 GST_DEBUG_FUNCPTR_NAME (unlink));
1348 * gst_pad_set_getcaps_function:
1350 * @getcaps: the #GstPadGetCapsFunction to set.
1352 * Sets the given getcaps function for the pad. @getcaps should return the
1353 * allowable caps for a pad in the context of the element's state, its link to
1354 * other elements, and the devices or files it has opened. These caps must be a
1355 * subset of the pad template caps. In the NULL state with no links, @getcaps
1356 * should ideally return the same caps as the pad template. In rare
1357 * circumstances, an object property can affect the caps returned by @getcaps,
1358 * but this is discouraged.
1360 * You do not need to call this function if @pad's allowed caps are always the
1361 * same as the pad template caps. This can only be true if the padtemplate
1362 * has fixed simple caps.
1364 * For most filters, the caps returned by @getcaps is directly affected by the
1365 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1366 * the srcpad's getcaps function is directly related to the stream data. Again,
1367 * @getcaps should return the most specific caps it reasonably can, since this
1368 * helps with autoplugging.
1370 * Note that the return value from @getcaps is owned by the caller, so the caller
1371 * should unref the caps after usage.
1374 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1376 g_return_if_fail (GST_IS_PAD (pad));
1378 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1379 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
1380 GST_DEBUG_FUNCPTR_NAME (getcaps));
1384 * gst_pad_set_acceptcaps_function:
1386 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1388 * Sets the given acceptcaps function for the pad. The acceptcaps function
1389 * will be called to check if the pad can accept the given caps. Setting the
1390 * acceptcaps function to NULL restores the default behaviour of allowing
1391 * any caps that matches the caps from gst_pad_get_caps.
1394 gst_pad_set_acceptcaps_function (GstPad * pad,
1395 GstPadAcceptCapsFunction acceptcaps)
1397 g_return_if_fail (GST_IS_PAD (pad));
1399 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1400 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
1401 GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1405 * gst_pad_set_fixatecaps_function:
1407 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1409 * Sets the given fixatecaps function for the pad. The fixatecaps function
1410 * will be called whenever the default values for a GstCaps needs to be
1414 gst_pad_set_fixatecaps_function (GstPad * pad,
1415 GstPadFixateCapsFunction fixatecaps)
1417 g_return_if_fail (GST_IS_PAD (pad));
1419 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1420 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
1421 GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1425 * gst_pad_set_setcaps_function:
1427 * @setcaps: the #GstPadSetCapsFunction to set.
1429 * Sets the given setcaps function for the pad. The setcaps function
1430 * will be called whenever a buffer with a new media type is pushed or
1431 * pulled from the pad. The pad/element needs to update its internal
1432 * structures to process the new media type. If this new type is not
1433 * acceptable, the setcaps function should return FALSE.
1436 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1438 g_return_if_fail (GST_IS_PAD (pad));
1440 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1441 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
1442 GST_DEBUG_FUNCPTR_NAME (setcaps));
1446 * gst_pad_set_bufferalloc_function:
1447 * @pad: a sink #GstPad.
1448 * @bufalloc: the #GstPadBufferAllocFunction to set.
1450 * Sets the given bufferalloc function for the pad. Note that the
1451 * bufferalloc function can only be set on sinkpads.
1454 gst_pad_set_bufferalloc_function (GstPad * pad,
1455 GstPadBufferAllocFunction bufalloc)
1457 g_return_if_fail (GST_IS_PAD (pad));
1458 g_return_if_fail (GST_PAD_IS_SINK (pad));
1460 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1461 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
1462 GST_DEBUG_FUNCPTR_NAME (bufalloc));
1467 * @srcpad: the source #GstPad to unlink.
1468 * @sinkpad: the sink #GstPad to unlink.
1470 * Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
1473 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1474 * the pads were not linked together.
1479 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1481 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1482 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1484 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1485 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1486 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1488 GST_OBJECT_LOCK (srcpad);
1490 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1493 GST_OBJECT_LOCK (sinkpad);
1495 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1498 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1499 goto not_linked_together;
1501 if (GST_PAD_UNLINKFUNC (srcpad)) {
1502 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1504 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1505 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1508 /* first clear peers */
1509 GST_PAD_PEER (srcpad) = NULL;
1510 GST_PAD_PEER (sinkpad) = NULL;
1512 GST_OBJECT_UNLOCK (sinkpad);
1513 GST_OBJECT_UNLOCK (srcpad);
1515 /* fire off a signal to each of the pads telling them
1516 * that they've been unlinked */
1517 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1518 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1520 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1521 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1527 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1528 GST_OBJECT_UNLOCK (srcpad);
1533 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1534 GST_OBJECT_UNLOCK (sinkpad);
1535 GST_OBJECT_UNLOCK (srcpad);
1538 not_linked_together:
1540 /* we do not emit a warning in this case because unlinking cannot
1541 * be made MT safe.*/
1542 GST_OBJECT_UNLOCK (sinkpad);
1543 GST_OBJECT_UNLOCK (srcpad);
1549 * gst_pad_is_linked:
1550 * @pad: pad to check
1552 * Checks if a @pad is linked to another pad or not.
1554 * Returns: TRUE if the pad is linked, FALSE otherwise.
1559 gst_pad_is_linked (GstPad * pad)
1563 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1565 GST_OBJECT_LOCK (pad);
1566 result = (GST_PAD_PEER (pad) != NULL);
1567 GST_OBJECT_UNLOCK (pad);
1572 /* get the caps from both pads and see if the intersection
1575 * This function should be called with the pad LOCK on both
1579 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1585 srccaps = gst_pad_get_caps_unlocked (src);
1586 sinkcaps = gst_pad_get_caps_unlocked (sink);
1588 GST_CAT_DEBUG (GST_CAT_CAPS, "src caps %" GST_PTR_FORMAT, srccaps);
1589 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1591 /* if we have caps on both pads we can check the intersection. If one
1592 * of the caps is NULL, we return TRUE. */
1593 if (srccaps == NULL || sinkcaps == NULL)
1596 icaps = gst_caps_intersect (srccaps, sinkcaps);
1597 gst_caps_unref (srccaps);
1598 gst_caps_unref (sinkcaps);
1603 GST_CAT_DEBUG (GST_CAT_CAPS,
1604 "intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
1606 if (gst_caps_is_empty (icaps))
1609 gst_caps_unref (icaps);
1614 /* incompatible cases */
1617 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection gave NULL");
1622 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is EMPTY");
1623 gst_caps_unref (icaps);
1628 /* check if the grandparents of both pads are the same.
1629 * This check is required so that we don't try to link
1630 * pads from elements in different bins without ghostpads.
1632 * The LOCK should be held on both pads
1635 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1637 GstObject *psrc, *psink;
1638 gboolean res = TRUE;
1640 psrc = GST_OBJECT_PARENT (src);
1641 psink = GST_OBJECT_PARENT (sink);
1643 /* if one of the pads has no parent, we allow the link */
1644 if (psrc && psink) {
1645 /* if the parents are the same, we have a loop */
1646 if (G_UNLIKELY (psrc == psink))
1649 /* if they both have a parent, we check the grandparents */
1650 psrc = gst_object_get_parent (psrc);
1651 psink = gst_object_get_parent (psink);
1653 if (G_UNLIKELY (psrc != psink)) {
1654 /* if they have grandparents but they are not the same */
1655 GST_CAT_DEBUG (GST_CAT_CAPS,
1656 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1657 GST_PTR_FORMAT, psrc, psink);
1661 gst_object_unref (psrc);
1663 gst_object_unref (psink);
1671 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1678 /* FIXME leftover from an attempt at refactoring... */
1679 /* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
1680 * the two pads will be locked in the srcpad, sinkpad order. */
1681 static GstPadLinkReturn
1682 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1684 /* generic checks */
1685 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
1686 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
1688 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1689 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1691 GST_OBJECT_LOCK (srcpad);
1693 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1696 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1697 goto src_was_linked;
1699 GST_OBJECT_LOCK (sinkpad);
1701 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1704 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1705 goto sink_was_linked;
1707 /* check hierarchy, pads can only be linked if the grandparents
1709 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1710 goto wrong_hierarchy;
1712 /* check pad caps for non-empty intersection */
1713 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1716 /* FIXME check pad scheduling for non-empty intersection */
1718 return GST_PAD_LINK_OK;
1722 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1723 GST_OBJECT_UNLOCK (srcpad);
1724 return GST_PAD_LINK_WRONG_DIRECTION;
1728 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
1729 GST_DEBUG_PAD_NAME (srcpad),
1730 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1731 /* we do not emit a warning in this case because unlinking cannot
1732 * be made MT safe.*/
1733 GST_OBJECT_UNLOCK (srcpad);
1734 return GST_PAD_LINK_WAS_LINKED;
1738 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1739 GST_OBJECT_UNLOCK (sinkpad);
1740 GST_OBJECT_UNLOCK (srcpad);
1741 return GST_PAD_LINK_WRONG_DIRECTION;
1745 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
1746 GST_DEBUG_PAD_NAME (sinkpad),
1747 GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
1748 /* we do not emit a warning in this case because unlinking cannot
1749 * be made MT safe.*/
1750 GST_OBJECT_UNLOCK (sinkpad);
1751 GST_OBJECT_UNLOCK (srcpad);
1752 return GST_PAD_LINK_WAS_LINKED;
1756 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1757 GST_OBJECT_UNLOCK (sinkpad);
1758 GST_OBJECT_UNLOCK (srcpad);
1759 return GST_PAD_LINK_WRONG_HIERARCHY;
1763 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1764 GST_OBJECT_UNLOCK (sinkpad);
1765 GST_OBJECT_UNLOCK (srcpad);
1766 return GST_PAD_LINK_NOFORMAT;
1772 * @srcpad: the source #GstPad to link.
1773 * @sinkpad: the sink #GstPad to link.
1775 * Links the source pad and the sink pad.
1777 * Returns: A result code indicating if the connection worked or
1783 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1785 GstPadLinkReturn result;
1787 /* prepare will also lock the two pads */
1788 result = gst_pad_link_prepare (srcpad, sinkpad);
1790 if (result != GST_PAD_LINK_OK)
1791 goto prepare_failed;
1793 /* must set peers before calling the link function */
1794 GST_PAD_PEER (srcpad) = sinkpad;
1795 GST_PAD_PEER (sinkpad) = srcpad;
1797 GST_OBJECT_UNLOCK (sinkpad);
1798 GST_OBJECT_UNLOCK (srcpad);
1800 /* FIXME released the locks here, concurrent thread might link
1801 * something else. */
1802 if (GST_PAD_LINKFUNC (srcpad)) {
1803 /* this one will call the peer link function */
1804 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
1805 } else if (GST_PAD_LINKFUNC (sinkpad)) {
1806 /* if no source link function, we need to call the sink link
1807 * function ourselves. */
1808 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
1810 result = GST_PAD_LINK_OK;
1813 GST_OBJECT_LOCK (srcpad);
1814 GST_OBJECT_LOCK (sinkpad);
1816 if (result == GST_PAD_LINK_OK) {
1817 GST_OBJECT_UNLOCK (sinkpad);
1818 GST_OBJECT_UNLOCK (srcpad);
1820 /* fire off a signal to each of the pads telling them
1821 * that they've been linked */
1822 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
1823 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
1825 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
1826 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1828 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
1829 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1831 GST_PAD_PEER (srcpad) = NULL;
1832 GST_PAD_PEER (sinkpad) = NULL;
1834 GST_OBJECT_UNLOCK (sinkpad);
1835 GST_OBJECT_UNLOCK (srcpad);
1846 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
1848 GstPadTemplate **template_p;
1850 /* this function would need checks if it weren't static */
1852 GST_OBJECT_LOCK (pad);
1853 template_p = &pad->padtemplate;
1854 gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
1855 GST_OBJECT_UNLOCK (pad);
1858 gst_pad_template_pad_created (templ, pad);
1862 * gst_pad_get_pad_template:
1865 * Gets the template for @pad.
1867 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
1868 * if this pad has no template.
1870 * FIXME: currently returns an unrefcounted padtemplate.
1873 gst_pad_get_pad_template (GstPad * pad)
1875 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1877 return GST_PAD_PAD_TEMPLATE (pad);
1881 /* should be called with the pad LOCK held */
1882 /* refs the caps, so caller is responsible for getting it unreffed */
1884 gst_pad_get_caps_unlocked (GstPad * pad)
1886 GstCaps *result = NULL;
1888 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
1890 if (GST_PAD_GETCAPSFUNC (pad)) {
1891 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1892 "dispatching to pad getcaps function");
1894 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
1895 GST_OBJECT_UNLOCK (pad);
1896 result = GST_PAD_GETCAPSFUNC (pad) (pad);
1897 GST_OBJECT_LOCK (pad);
1898 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
1900 if (result == NULL) {
1901 g_critical ("pad %s:%s returned NULL caps from getcaps function",
1902 GST_DEBUG_PAD_NAME (pad));
1904 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1905 "pad getcaps returned %" GST_PTR_FORMAT, result);
1906 #ifndef G_DISABLE_ASSERT
1907 /* check that the returned caps are a real subset of the template caps */
1908 if (GST_PAD_PAD_TEMPLATE (pad)) {
1909 const GstCaps *templ_caps =
1910 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
1911 if (!gst_caps_is_subset (result, templ_caps)) {
1914 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
1915 "pad returned caps %" GST_PTR_FORMAT
1916 " which are not a real subset of its template caps %"
1917 GST_PTR_FORMAT, result, templ_caps);
1919 ("pad %s:%s returned caps that are not a real subset of its template caps",
1920 GST_DEBUG_PAD_NAME (pad));
1921 temp = gst_caps_intersect (templ_caps, result);
1922 gst_caps_unref (result);
1930 if (GST_PAD_PAD_TEMPLATE (pad)) {
1931 GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
1933 result = GST_PAD_TEMPLATE_CAPS (templ);
1934 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1935 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
1938 result = gst_caps_ref (result);
1941 if (GST_PAD_CAPS (pad)) {
1942 result = GST_PAD_CAPS (pad);
1944 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1945 "using pad caps %p %" GST_PTR_FORMAT, result, result);
1947 result = gst_caps_ref (result);
1951 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
1952 result = gst_caps_new_empty ();
1960 * @pad: a #GstPad to get the capabilities of.
1962 * Gets the capabilities this pad can produce or consume.
1963 * Note that this method doesn't necessarily return the caps set by
1964 * gst_pad_set_caps() - use #GST_PAD_CAPS for that instead.
1965 * gst_pad_get_caps returns all possible caps a pad can operate with, using
1966 * the pad's get_caps function;
1967 * this returns the pad template caps if not explicitly set.
1969 * Returns: a newly allocated copy of the #GstCaps of this pad.
1974 gst_pad_get_caps (GstPad * pad)
1976 GstCaps *result = NULL;
1978 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1980 GST_OBJECT_LOCK (pad);
1982 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
1984 result = gst_pad_get_caps_unlocked (pad);
1985 GST_OBJECT_UNLOCK (pad);
1991 * gst_pad_peer_get_caps:
1992 * @pad: a #GstPad to get the peer capabilities of.
1994 * Gets the capabilities of the peer connected to this pad.
1996 * Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
1997 * gst_caps_unref to get rid of it. this function returns NULL if there is no
2001 gst_pad_peer_get_caps (GstPad * pad)
2004 GstCaps *result = NULL;
2006 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2008 GST_OBJECT_LOCK (pad);
2010 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2012 peerpad = GST_PAD_PEER (pad);
2013 if (G_UNLIKELY (peerpad == NULL))
2016 gst_object_ref (peerpad);
2017 GST_OBJECT_UNLOCK (pad);
2019 result = gst_pad_get_caps (peerpad);
2021 gst_object_unref (peerpad);
2027 GST_OBJECT_UNLOCK (pad);
2033 fixate_value (GValue * dest, const GValue * src)
2035 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
2036 g_value_init (dest, G_TYPE_INT);
2037 g_value_set_int (dest, gst_value_get_int_range_min (src));
2038 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
2039 g_value_init (dest, G_TYPE_DOUBLE);
2040 g_value_set_double (dest, gst_value_get_double_range_min (src));
2041 } else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
2042 gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
2043 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
2044 GValue temp = { 0 };
2046 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
2047 if (!fixate_value (dest, &temp))
2048 gst_value_init_and_copy (dest, &temp);
2049 g_value_unset (&temp);
2050 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
2051 gboolean res = FALSE;
2054 g_value_init (dest, GST_TYPE_ARRAY);
2055 for (n = 0; n < gst_value_array_get_size (src); n++) {
2057 const GValue *orig_kid = gst_value_array_get_value (src, n);
2059 if (!fixate_value (&kid, orig_kid))
2060 gst_value_init_and_copy (&kid, orig_kid);
2063 gst_value_array_append_value (dest, &kid);
2064 g_value_unset (&kid);
2068 g_value_unset (dest);
2079 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
2081 GstStructure *s = data;
2084 if (fixate_value (&v, value)) {
2085 gst_structure_id_set_value (s, field_id, &v);
2093 * gst_pad_fixate_caps:
2094 * @pad: a #GstPad to fixate
2095 * @caps: the #GstCaps to fixate
2097 * Fixate a caps on the given pad. Modifies the caps in place, so you should
2098 * make sure that the caps are actually writable (see gst_caps_make_writable()).
2101 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
2103 GstPadFixateCapsFunction fixatefunc;
2106 g_return_if_fail (GST_IS_PAD (pad));
2107 g_return_if_fail (caps != NULL);
2109 if (gst_caps_is_fixed (caps))
2112 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
2114 fixatefunc (pad, caps);
2117 /* default fixation */
2118 for (n = 0; n < gst_caps_get_size (caps); n++) {
2119 GstStructure *s = gst_caps_get_structure (caps, n);
2121 gst_structure_foreach (s, gst_pad_default_fixate, s);
2125 /* Default accept caps implementation just checks against
2126 * against the allowed caps for the pad */
2128 gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
2130 /* get the caps and see if it intersects to something
2134 gboolean result = FALSE;
2136 allowed = gst_pad_get_caps (pad);
2138 intersect = gst_caps_intersect (allowed, caps);
2140 result = !gst_caps_is_empty (intersect);
2142 gst_caps_unref (allowed);
2143 gst_caps_unref (intersect);
2150 * gst_pad_accept_caps:
2151 * @pad: a #GstPad to check
2152 * @caps: a #GstCaps to check on the pad
2154 * Check if the given pad accepts the caps.
2156 * Returns: TRUE if the pad can accept the caps.
2159 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2162 GstPadAcceptCapsFunction acceptfunc;
2163 GstCaps *existing = NULL;
2165 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2167 /* any pad can be unnegotiated */
2171 /* lock for checking the existing caps */
2172 GST_OBJECT_LOCK (pad);
2173 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2174 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
2175 /* The current caps on a pad are trivially acceptable */
2176 if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
2177 if (caps == existing || gst_caps_is_equal (caps, existing))
2180 GST_OBJECT_UNLOCK (pad);
2182 if (G_LIKELY (acceptfunc)) {
2183 /* we can call the function */
2184 result = acceptfunc (pad, caps);
2186 /* Only null if the element explicitly unset it */
2187 result = gst_pad_acceptcaps_default (pad, caps);
2193 GST_OBJECT_UNLOCK (pad);
2199 * gst_pad_peer_accept_caps:
2200 * @pad: a #GstPad to check the peer of
2201 * @caps: a #GstCaps to check on the pad
2203 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2206 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2209 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2214 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2216 GST_OBJECT_LOCK (pad);
2218 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
2220 peerpad = GST_PAD_PEER (pad);
2221 if (G_UNLIKELY (peerpad == NULL))
2224 result = gst_pad_accept_caps (peerpad, caps);
2225 GST_OBJECT_UNLOCK (pad);
2231 GST_OBJECT_UNLOCK (pad);
2238 * @pad: a #GstPad to set the capabilities of.
2239 * @caps: a #GstCaps to set.
2241 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2242 * caps on the pad will be unreffed. This function refs the caps so you should
2243 * unref if as soon as you don't need it anymore.
2244 * It is possible to set NULL caps, which will make the pad unnegotiated
2247 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2248 * or bad parameters were provided to this function.
2253 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2255 GstPadSetCapsFunction setcaps;
2258 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2259 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2261 GST_OBJECT_LOCK (pad);
2262 existing = GST_PAD_CAPS (pad);
2263 if (existing == caps)
2266 if (gst_caps_is_equal (caps, existing))
2267 goto setting_same_caps;
2269 setcaps = GST_PAD_SETCAPSFUNC (pad);
2271 /* call setcaps function to configure the pad only if the
2272 * caps is not NULL */
2273 if (setcaps != NULL && caps) {
2274 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2275 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2276 GST_OBJECT_UNLOCK (pad);
2277 if (!setcaps (pad, caps))
2279 GST_OBJECT_LOCK (pad);
2280 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2282 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
2286 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2287 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %" GST_PTR_FORMAT, caps);
2288 GST_OBJECT_UNLOCK (pad);
2290 g_object_notify (G_OBJECT (pad), "caps");
2296 GST_OBJECT_UNLOCK (pad);
2301 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2302 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2303 "caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
2304 GST_OBJECT_UNLOCK (pad);
2311 GST_OBJECT_LOCK (pad);
2312 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2313 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2314 "caps %" GST_PTR_FORMAT " could not be set", caps);
2315 GST_OBJECT_UNLOCK (pad);
2322 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2324 GstPadSetCapsFunction setcaps;
2327 setcaps = GST_PAD_SETCAPSFUNC (pad);
2329 /* See if pad accepts the caps - only needed if
2330 * no setcaps function */
2331 if (setcaps == NULL)
2332 if (!gst_pad_accept_caps (pad, caps))
2335 /* set caps on pad if call succeeds */
2336 res = gst_pad_set_caps (pad, caps);
2337 /* no need to unref the caps here, set_caps takes a ref and
2338 * our ref goes away when we leave this function. */
2344 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2345 "caps %" GST_PTR_FORMAT " not accepted", caps);
2350 /* returns TRUE if the src pad could be configured to accept the given caps */
2352 gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
2354 GstPadSetCapsFunction setcaps;
2357 setcaps = GST_PAD_SETCAPSFUNC (pad);
2359 /* See if pad accepts the caps - only needed if
2360 * no setcaps function */
2361 if (setcaps == NULL)
2362 if (!gst_pad_accept_caps (pad, caps))
2366 res = gst_pad_set_caps (pad, caps);
2374 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2375 "caps %" GST_PTR_FORMAT " not accepted", caps);
2381 * gst_pad_get_pad_template_caps:
2382 * @pad: a #GstPad to get the template capabilities from.
2384 * Gets the capabilities for @pad's template.
2386 * Returns: the #GstCaps of this pad template. If you intend to keep a reference
2387 * on the caps, make a copy (see gst_caps_copy ()).
2390 gst_pad_get_pad_template_caps (GstPad * pad)
2392 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2394 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2396 if (GST_PAD_PAD_TEMPLATE (pad))
2397 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2399 return gst_static_caps_get (&anycaps);
2405 * @pad: a #GstPad to get the peer of.
2407 * Gets the peer of @pad. This function refs the peer pad so
2408 * you need to unref it after use.
2410 * Returns: the peer #GstPad. Unref after usage.
2415 gst_pad_get_peer (GstPad * pad)
2419 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2421 GST_OBJECT_LOCK (pad);
2422 result = GST_PAD_PEER (pad);
2424 gst_object_ref (result);
2425 GST_OBJECT_UNLOCK (pad);
2431 * gst_pad_get_allowed_caps:
2432 * @srcpad: a #GstPad, it must a a source pad.
2434 * Gets the capabilities of the allowed media types that can flow through
2435 * @srcpad and its peer. The pad must be a source pad.
2436 * The caller must free the resulting caps.
2438 * Returns: the allowed #GstCaps of the pad link. Free the caps when
2439 * you no longer need it. This function returns NULL when the @srcpad has no
2445 gst_pad_get_allowed_caps (GstPad * srcpad)
2452 g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
2453 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
2455 GST_OBJECT_LOCK (srcpad);
2457 peer = GST_PAD_PEER (srcpad);
2458 if (G_UNLIKELY (peer == NULL))
2461 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "getting allowed caps");
2463 gst_object_ref (peer);
2464 GST_OBJECT_UNLOCK (srcpad);
2465 mycaps = gst_pad_get_caps (srcpad);
2467 peercaps = gst_pad_get_caps (peer);
2468 gst_object_unref (peer);
2470 caps = gst_caps_intersect (mycaps, peercaps);
2471 gst_caps_unref (peercaps);
2472 gst_caps_unref (mycaps);
2474 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, srcpad, "allowed caps %" GST_PTR_FORMAT,
2481 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "no peer");
2482 GST_OBJECT_UNLOCK (srcpad);
2489 * gst_pad_get_negotiated_caps:
2492 * Gets the capabilities of the media type that currently flows through @pad
2495 * This function can be used on both src and sinkpads. Note that srcpads are
2496 * always negotiated before sinkpads so it is possible that the negotiated caps
2497 * on the srcpad do not match the negotiated caps of the peer.
2499 * Returns: the negotiated #GstCaps of the pad link. Free the caps when
2500 * you no longer need it. This function returns NULL when the @pad has no
2501 * peer or is not negotiated yet.
2506 gst_pad_get_negotiated_caps (GstPad * pad)
2511 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2513 GST_OBJECT_LOCK (pad);
2515 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2518 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
2520 caps = GST_PAD_CAPS (pad);
2522 gst_caps_ref (caps);
2523 GST_OBJECT_UNLOCK (pad);
2525 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
2532 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2533 GST_OBJECT_UNLOCK (pad);
2539 /* calls the buffer_alloc function on the given pad */
2540 static GstFlowReturn
2541 gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
2542 GstCaps * caps, GstBuffer ** buf)
2545 GstPadBufferAllocFunction bufferallocfunc;
2547 GST_OBJECT_LOCK (pad);
2548 /* when the pad is flushing we cannot give a buffer */
2549 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2552 if (offset == GST_BUFFER_OFFSET_NONE) {
2553 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2554 "calling bufferallocfunc &%s (@%p) for size %d offset NONE",
2555 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), &bufferallocfunc, size);
2557 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2558 "calling bufferallocfunc &%s (@%p) of for size %d offset %"
2559 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2560 &bufferallocfunc, size, offset);
2562 GST_OBJECT_UNLOCK (pad);
2564 /* G_LIKELY for now since most elements don't implement a buffer alloc
2565 * function and there is no default alloc proxy function as this is usually
2567 if (G_LIKELY ((bufferallocfunc = pad->bufferallocfunc) == NULL))
2570 ret = bufferallocfunc (pad, offset, size, caps, buf);
2571 if (G_UNLIKELY (ret != GST_FLOW_OK))
2573 /* no error, but NULL buffer means fallback to the default */
2574 if (G_UNLIKELY (*buf == NULL))
2577 /* If the buffer alloc function didn't set up the caps like it should,
2579 if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
2580 GST_WARNING_OBJECT (pad,
2581 "Buffer allocation function did not set caps. Setting");
2582 gst_buffer_set_caps (*buf, caps);
2588 /* pad was flushing */
2589 GST_OBJECT_UNLOCK (pad);
2590 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
2591 return GST_FLOW_WRONG_STATE;
2595 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2596 "alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
2601 /* fallback case, allocate a buffer of our own, add pad caps. */
2602 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
2604 *buf = gst_buffer_new_and_alloc (size);
2605 GST_BUFFER_OFFSET (*buf) = offset;
2606 gst_buffer_set_caps (*buf, caps);
2612 static GstFlowReturn
2613 gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
2614 GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
2618 gboolean caps_changed;
2620 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2621 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2622 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2624 GST_OBJECT_LOCK (pad);
2625 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2626 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
2629 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2632 gst_object_ref (peer);
2633 GST_OBJECT_UNLOCK (pad);
2635 ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
2636 gst_object_unref (peer);
2638 if (G_UNLIKELY (ret != GST_FLOW_OK))
2641 /* FIXME, move capnego this into a base class? */
2642 caps = GST_BUFFER_CAPS (*buf);
2644 /* Lock for checking caps, pretty pointless as the _pad_push() function might
2645 * change it concurrently, one of the problems with automatic caps setting in
2646 * pad_alloc_and_set_caps. Worst case, if does a check too much, but only when
2647 * there is heavy renegotiation going on in both directions. */
2648 GST_OBJECT_LOCK (pad);
2649 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2650 GST_OBJECT_UNLOCK (pad);
2652 /* we got a new datatype on the pad, see if it can handle it */
2653 if (G_UNLIKELY (caps_changed)) {
2654 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
2655 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, setcaps)))
2656 goto not_negotiated;
2662 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
2663 GST_OBJECT_UNLOCK (pad);
2668 /* pad has no peer */
2669 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2670 "called bufferallocfunc but had no peer");
2671 GST_OBJECT_UNLOCK (pad);
2672 return GST_FLOW_NOT_LINKED;
2676 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2677 "alloc function returned error %s", gst_flow_get_name (ret));
2682 gst_buffer_unref (*buf);
2684 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2685 "alloc function returned unacceptable buffer");
2686 return GST_FLOW_NOT_NEGOTIATED;
2691 * gst_pad_alloc_buffer:
2692 * @pad: a source #GstPad
2693 * @offset: the offset of the new buffer in the stream
2694 * @size: the size of the new buffer
2695 * @caps: the caps of the new buffer
2696 * @buf: a newly allocated buffer
2698 * Allocates a new, empty buffer optimized to push to pad @pad. This
2699 * function only works if @pad is a source pad and has a peer.
2701 * A new, empty #GstBuffer will be put in the @buf argument.
2702 * You need to check the caps of the buffer after performing this
2703 * function and renegotiate to the format if needed.
2705 * Returns: a result code indicating success of the operation. Any
2706 * result code other than #GST_FLOW_OK is an error and @buf should
2708 * An error can occur if the pad is not connected or when the downstream
2709 * peer elements cannot provide an acceptable buffer.
2714 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
2717 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
2721 * gst_pad_alloc_buffer_and_set_caps:
2722 * @pad: a source #GstPad
2723 * @offset: the offset of the new buffer in the stream
2724 * @size: the size of the new buffer
2725 * @caps: the caps of the new buffer
2726 * @buf: a newly allocated buffer
2728 * In addition to the function gst_pad_alloc_buffer(), this function
2729 * automatically calls gst_pad_set_caps() when the caps of the
2730 * newly allocated buffer are different from the @pad caps.
2732 * Returns: a result code indicating success of the operation. Any
2733 * result code other than #GST_FLOW_OK is an error and @buf should
2735 * An error can occur if the pad is not connected or when the downstream
2736 * peer elements cannot provide an acceptable buffer.
2741 gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
2742 GstCaps * caps, GstBuffer ** buf)
2744 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
2748 * gst_pad_get_internal_links_default:
2749 * @pad: the #GstPad to get the internal links of.
2751 * Gets a list of pads to which the given pad is linked to
2752 * inside of the parent element.
2753 * This is the default handler, and thus returns a list of all of the
2754 * pads inside the parent element with opposite direction.
2755 * The caller must free this list after use.
2757 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
2762 gst_pad_get_internal_links_default (GstPad * pad)
2767 GstPadDirection direction;
2769 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2771 direction = pad->direction;
2773 parent = GST_PAD_PARENT (pad);
2777 parent_pads = parent->pads;
2779 while (parent_pads) {
2780 GstPad *parent_pad = GST_PAD_CAST (parent_pads->data);
2782 if (parent_pad->direction != direction) {
2783 res = g_list_prepend (res, parent_pad);
2786 parent_pads = g_list_next (parent_pads);
2793 * gst_pad_get_internal_links:
2794 * @pad: the #GstPad to get the internal links of.
2796 * Gets a list of pads to which the given pad is linked to
2797 * inside of the parent element.
2798 * The caller must free this list after use.
2800 * Returns: a newly allocated #GList of pads.
2805 gst_pad_get_internal_links (GstPad * pad)
2809 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2811 if (GST_PAD_INTLINKFUNC (pad))
2812 res = GST_PAD_INTLINKFUNC (pad) (pad);
2819 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
2824 GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
2827 result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
2829 orig = pads = gst_pad_get_internal_links (pad);
2832 GstPad *eventpad = GST_PAD_CAST (pads->data);
2834 pads = g_list_next (pads);
2836 if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
2837 /* for each pad we send to, we should ref the event; it's up
2838 * to downstream to unref again when handled. */
2839 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
2840 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2841 gst_event_ref (event);
2842 gst_pad_push_event (eventpad, event);
2844 /* we only send the event on one pad, multi-sinkpad elements
2845 * should implement a handler */
2846 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
2847 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2848 result = gst_pad_push_event (eventpad, event);
2852 /* we handled the incoming event so we unref once */
2853 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
2854 gst_event_unref (event);
2863 * gst_pad_event_default:
2864 * @pad: a #GstPad to call the default event handler on.
2865 * @event: the #GstEvent to handle.
2867 * Invokes the default event handler for the given pad. End-of-stream and
2868 * discontinuity events are handled specially, and then the event is sent to all
2869 * pads internally linked to @pad. Note that if there are many possible sink
2870 * pads that are internally linked to @pad, only one will be sent an event.
2871 * Multi-sinkpad elements should implement custom event handlers.
2873 * Returns: TRUE if the event was sent succesfully.
2876 gst_pad_event_default (GstPad * pad, GstEvent * event)
2878 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2879 g_return_val_if_fail (event != NULL, FALSE);
2881 switch (GST_EVENT_TYPE (event)) {
2884 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
2885 gst_pad_pause_task (pad);
2891 return gst_pad_event_default_dispatch (pad, event);
2895 * gst_pad_dispatcher:
2896 * @pad: a #GstPad to dispatch.
2897 * @dispatch: the #GstDispatcherFunction to call.
2898 * @data: gpointer user data passed to the dispatcher function.
2900 * Invokes the given dispatcher function on all pads that are
2901 * internally linked to the given pad.
2902 * The GstPadDispatcherFunction should return TRUE when no further pads
2903 * need to be processed.
2905 * Returns: TRUE if one of the dispatcher functions returned TRUE.
2908 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
2911 gboolean res = FALSE;
2912 GList *int_pads, *orig;
2914 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2915 g_return_val_if_fail (dispatch != NULL, FALSE);
2917 orig = int_pads = gst_pad_get_internal_links (pad);
2920 GstPad *int_pad = GST_PAD_CAST (int_pads->data);
2921 GstPad *int_peer = GST_PAD_PEER (int_pad);
2924 res = dispatch (int_peer, data);
2928 int_pads = g_list_next (int_pads);
2938 * @pad: a #GstPad to invoke the default query on.
2939 * @query: the #GstQuery to perform.
2941 * Dispatches a query to a pad. The query should have been allocated by the
2942 * caller via one of the type-specific allocation functions in gstquery.h. The
2943 * element is responsible for filling the query with an appropriate response,
2944 * which should then be parsed with a type-specific query parsing function.
2946 * Again, the caller is responsible for both the allocation and deallocation of
2947 * the query structure.
2949 * Returns: TRUE if the query could be performed.
2952 gst_pad_query (GstPad * pad, GstQuery * query)
2954 GstPadQueryFunction func;
2956 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2957 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2959 GST_DEBUG_OBJECT (pad, "sending query %p", query);
2961 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
2964 return func (pad, query);
2968 GST_DEBUG_OBJECT (pad, "had no query function");
2974 * gst_pad_query_default:
2975 * @pad: a #GstPad to call the default query handler on.
2976 * @query: the #GstQuery to handle.
2978 * Invokes the default query handler for the given pad.
2979 * The query is sent to all pads internally linked to @pad. Note that
2980 * if there are many possible sink pads that are internally linked to
2981 * @pad, only one will be sent the query.
2982 * Multi-sinkpad elements should implement custom query handlers.
2984 * Returns: TRUE if the query was performed succesfully.
2987 gst_pad_query_default (GstPad * pad, GstQuery * query)
2989 switch (GST_QUERY_TYPE (query)) {
2990 case GST_QUERY_POSITION:
2991 case GST_QUERY_SEEKING:
2992 case GST_QUERY_FORMATS:
2993 case GST_QUERY_LATENCY:
2994 case GST_QUERY_JITTER:
2995 case GST_QUERY_RATE:
2996 case GST_QUERY_CONVERT:
2998 return gst_pad_dispatcher
2999 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
3003 #ifndef GST_DISABLE_LOADSAVE
3004 /* FIXME: why isn't this on a GstElement ? */
3006 * gst_pad_load_and_link:
3007 * @self: an #xmlNodePtr to read the description from.
3008 * @parent: the #GstObject element that owns the pad.
3010 * Reads the pad definition from the XML node and links the given pad
3011 * in the element to a pad of an element up in the hierarchy.
3014 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
3016 xmlNodePtr field = self->xmlChildrenNode;
3017 GstPad *pad = NULL, *targetpad;
3021 GstObject *grandparent;
3025 if (!strcmp ((char *) field->name, "name")) {
3026 name = (gchar *) xmlNodeGetContent (field);
3027 pad = gst_element_get_pad (GST_ELEMENT (parent), name);
3029 } else if (!strcmp ((char *) field->name, "peer")) {
3030 peer = (gchar *) xmlNodeGetContent (field);
3032 field = field->next;
3034 g_return_if_fail (pad != NULL);
3039 split = g_strsplit (peer, ".", 2);
3041 if (split[0] == NULL || split[1] == NULL) {
3042 GST_CAT_DEBUG_OBJECT (GST_CAT_XML, pad,
3043 "Could not parse peer '%s', leaving unlinked", peer);
3050 g_return_if_fail (split[0] != NULL);
3051 g_return_if_fail (split[1] != NULL);
3053 grandparent = gst_object_get_parent (parent);
3055 if (grandparent && GST_IS_BIN (grandparent)) {
3056 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
3063 targetpad = gst_element_get_pad (target, split[1]);
3065 if (targetpad == NULL)
3068 gst_pad_link (pad, targetpad);
3075 * gst_pad_save_thyself:
3076 * @pad: a #GstPad to save.
3077 * @parent: the parent #xmlNodePtr to save the description in.
3079 * Saves the pad into an xml representation.
3081 * Returns: the #xmlNodePtr representation of the pad.
3084 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
3089 g_return_val_if_fail (GST_IS_PAD (object), NULL);
3091 pad = GST_PAD (object);
3093 xmlNewChild (parent, NULL, (xmlChar *) "name",
3094 (xmlChar *) GST_PAD_NAME (pad));
3095 if (GST_PAD_PEER (pad) != NULL) {
3098 peer = GST_PAD_PEER (pad);
3099 /* first check to see if the peer's parent's parent is the same */
3100 /* we just save it off */
3101 content = g_strdup_printf ("%s.%s",
3102 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
3103 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
3106 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
3113 * gst_ghost_pad_save_thyself:
3114 * @pad: a ghost #GstPad to save.
3115 * @parent: the parent #xmlNodePtr to save the description in.
3117 * Saves the ghost pad into an xml representation.
3119 * Returns: the #xmlNodePtr representation of the pad.
3122 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
3126 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
3128 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
3129 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
3130 xmlNewChild (self, NULL, (xmlChar *) "parent",
3131 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
3133 /* FIXME FIXME FIXME! */
3138 #endif /* GST_DISABLE_LOADSAVE */
3141 * should be called with pad OBJECT_LOCK and STREAM_LOCK held.
3142 * GST_PAD_IS_BLOCK (pad) == TRUE when this function is
3145 * This function perform the pad blocking when an event, buffer push
3146 * or buffer_alloc is performed on a _SRC_ pad. It blocks the
3147 * streaming thread after informing the pad has been blocked.
3149 * An application can with this method wait and block any streaming
3150 * thread and perform operations such as seeking or linking.
3152 * Two methods are available for notifying the application of the
3154 * - the callback method, which happens in the STREAMING thread with
3155 * the STREAM_LOCK held. With this method, the most usefull way of
3156 * dealing with the callback is to post a message to the main thread
3157 * where the pad block can then be handled outside of the streaming
3158 * thread. With the last method one can perform all operations such
3159 * as doing a state change, linking, unblocking, seeking etc on the
3161 * - the GCond signal method, which makes any thread unblock when
3162 * the pad block happens.
3166 static GstFlowReturn
3167 handle_pad_block (GstPad * pad)
3169 GstPadBlockCallback callback;
3171 GstFlowReturn ret = GST_FLOW_OK;
3173 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
3175 /* flushing, don't bother trying to block and return WRONG_STATE
3177 if (GST_PAD_IS_FLUSHING (pad))
3178 goto flushingnonref;
3180 /* we grab an extra ref for the callbacks, this is probably not
3181 * needed (callback code does not have a ref and cannot unref). I
3182 * think this was done to make it possible to unref the element in
3183 * the callback, which is in the end totally impossible as it
3184 * requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
3185 * all taken when calling this function. */
3186 gst_object_ref (pad);
3188 /* we either have a callback installed to notify the block or
3189 * some other thread is doing a GCond wait. */
3190 callback = pad->block_callback;
3192 /* there is a callback installed, call it. We release the
3193 * lock so that the callback can do something usefull with the
3195 user_data = pad->block_data;
3196 GST_OBJECT_UNLOCK (pad);
3197 callback (pad, TRUE, user_data);
3198 GST_OBJECT_LOCK (pad);
3200 /* no callback, signal the thread that is doing a GCond wait
3202 GST_PAD_BLOCK_SIGNAL (pad);
3205 /* OBJECT_LOCK could have been released when we did the callback, which
3206 * then could have made the pad unblock so we need to check the blocking
3207 * condition again. */
3208 while (GST_PAD_IS_BLOCKED (pad)) {
3209 if (GST_PAD_IS_FLUSHING (pad))
3212 /* now we block the streaming thread. It can be unlocked when we
3213 * deactivate the pad (which will also set the FLUSHING flag) or
3214 * when the pad is unblocked. A flushing event will also unblock
3215 * the pad after setting the FLUSHING flag. */
3216 GST_PAD_BLOCK_WAIT (pad);
3218 /* see if we got unlocked by a flush or not */
3219 if (GST_PAD_IS_FLUSHING (pad))
3223 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
3225 /* when we get here, the pad is unblocked again and we perform
3226 * the needed unblock code. */
3227 callback = pad->block_callback;
3229 /* we need to call the callback */
3230 user_data = pad->block_data;
3231 GST_OBJECT_UNLOCK (pad);
3232 callback (pad, FALSE, user_data);
3233 GST_OBJECT_LOCK (pad);
3235 /* we need to signal the thread waiting on the GCond */
3236 GST_PAD_BLOCK_SIGNAL (pad);
3239 gst_object_unref (pad);
3245 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
3246 return GST_FLOW_WRONG_STATE;
3250 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
3251 gst_object_unref (pad);
3252 return GST_FLOW_WRONG_STATE;
3256 /**********************************************************************
3257 * Data passing functions
3261 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
3264 GValue args[2] = { {0}, {0} };
3269 g_value_init (&ret, G_TYPE_BOOLEAN);
3270 g_value_set_boolean (&ret, TRUE);
3271 g_value_init (&args[0], GST_TYPE_PAD);
3272 g_value_set_object (&args[0], pad);
3273 g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
3274 gst_value_set_mini_object (&args[1], obj);
3276 if (GST_IS_EVENT (obj))
3277 detail = event_quark;
3279 detail = buffer_quark;
3282 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
3283 res = g_value_get_boolean (&ret);
3286 g_value_unset (&ret);
3287 g_value_unset (&args[0]);
3288 g_value_unset (&args[1]);
3293 /* this is the chain function that does not perform the additional argument
3294 * checking for that little extra speed.
3296 static inline GstFlowReturn
3297 gst_pad_chain_unchecked (GstPad * pad, GstBuffer * buffer)
3300 gboolean caps_changed;
3301 GstPadChainFunction chainfunc;
3303 gboolean emit_signal;
3305 GST_PAD_STREAM_LOCK (pad);
3307 GST_OBJECT_LOCK (pad);
3308 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3311 caps = GST_BUFFER_CAPS (buffer);
3312 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3314 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3315 GST_OBJECT_UNLOCK (pad);
3317 /* see if the signal should be emited, we emit before caps nego as
3318 * we might drop the buffer and do capsnego for nothing. */
3319 if (G_UNLIKELY (emit_signal)) {
3320 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3324 /* we got a new datatype on the pad, see if it can handle it */
3325 if (G_UNLIKELY (caps_changed)) {
3326 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3327 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
3328 goto not_negotiated;
3331 /* NOTE: we read the chainfunc unlocked.
3332 * we cannot hold the lock for the pad so we might send
3333 * the data to the wrong function. This is not really a
3334 * problem since functions are assigned at creation time
3335 * and don't change that often... */
3336 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
3339 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3340 "calling chainfunction &%s", GST_DEBUG_FUNCPTR_NAME (chainfunc));
3342 ret = chainfunc (pad, buffer);
3344 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3345 "called chainfunction &%s, returned %s",
3346 GST_DEBUG_FUNCPTR_NAME (chainfunc), gst_flow_get_name (ret));
3348 GST_PAD_STREAM_UNLOCK (pad);
3355 gst_buffer_unref (buffer);
3356 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3357 "pushing, but pad was flushing");
3358 GST_OBJECT_UNLOCK (pad);
3359 GST_PAD_STREAM_UNLOCK (pad);
3360 return GST_FLOW_WRONG_STATE;
3364 gst_buffer_unref (buffer);
3365 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3366 GST_PAD_STREAM_UNLOCK (pad);
3371 gst_buffer_unref (buffer);
3372 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3373 "pushing buffer but pad did not accept");
3374 GST_PAD_STREAM_UNLOCK (pad);
3375 return GST_FLOW_NOT_NEGOTIATED;
3379 gst_buffer_unref (buffer);
3380 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3381 "pushing, but not chainhandler");
3382 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3383 ("push on pad %s:%s but it has no chainfunction",
3384 GST_DEBUG_PAD_NAME (pad)));
3385 GST_PAD_STREAM_UNLOCK (pad);
3386 return GST_FLOW_NOT_SUPPORTED;
3392 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3393 * @buffer: the #GstBuffer to send, return GST_FLOW_ERROR if not.
3395 * Chain a buffer to @pad.
3397 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
3399 * If the caps on @buffer are different from the current caps on @pad, this
3400 * function will call any setcaps function (see gst_pad_set_setcaps_function())
3401 * installed on @pad. If the new caps are not acceptable for @pad, this function
3402 * returns #GST_FLOW_NOT_NEGOTIATED.
3404 * The function proceeds calling the chain function installed on @pad (see
3405 * gst_pad_set_chain_function()) and the return value of that function is
3406 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
3409 * In all cases, success or failure, the caller loses its reference to @buffer
3410 * after calling this function.
3412 * Returns: a #GstFlowReturn from the pad.
3417 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
3419 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3420 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3422 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3424 return gst_pad_chain_unchecked (pad, buffer);
3429 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
3430 * @buffer: the #GstBuffer to push returns GST_FLOW_ERROR if not.
3432 * Pushes a buffer to the peer of @pad.
3434 * This function will call an installed pad block before triggering any
3435 * installed pad probes.
3437 * If the caps on @buffer are different from the currently configured caps on
3438 * @pad, this function will call any installed setcaps function on @pad (see
3439 * gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
3440 * format, this function returns #GST_FLOW_NOT_NEGOTIATED.
3442 * The function proceeds calling gst_pad_chain() on the peer pad and returns the
3443 * value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will be
3446 * In all cases, success or failure, the caller loses its reference to @buffer
3447 * after calling this function.
3449 * Returns: a #GstFlowReturn from the peer pad.
3454 gst_pad_push (GstPad * pad, GstBuffer * buffer)
3460 gboolean caps_changed;
3462 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3463 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3464 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3466 GST_OBJECT_LOCK (pad);
3468 /* FIXME: this check can go away; pad_set_blocked could be implemented with
3469 * probes completely or probes with an extended pad block. */
3470 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3471 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
3474 /* we emit signals on the pad arg, the peer will have a chance to
3475 * emit in the _chain() function */
3476 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
3477 /* unlock before emitting */
3478 GST_OBJECT_UNLOCK (pad);
3480 /* if the signal handler returned FALSE, it means we should just drop the
3482 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3485 GST_OBJECT_LOCK (pad);
3488 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3491 /* take ref to peer pad before releasing the lock */
3492 gst_object_ref (peer);
3494 /* Before pushing the buffer to the peer pad, ensure that caps
3495 * are set on this pad */
3496 caps = GST_BUFFER_CAPS (buffer);
3497 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3499 GST_OBJECT_UNLOCK (pad);
3501 /* we got a new datatype from the pad, it had better handle it */
3502 if (G_UNLIKELY (caps_changed)) {
3503 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3504 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
3505 goto not_negotiated;
3508 ret = gst_pad_chain_unchecked (peer, buffer);
3510 gst_object_unref (peer);
3514 /* ERROR recovery here */
3517 gst_buffer_unref (buffer);
3518 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
3519 GST_OBJECT_UNLOCK (pad);
3524 gst_buffer_unref (buffer);
3525 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3530 gst_buffer_unref (buffer);
3531 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3532 "pushing, but it was not linked");
3533 GST_OBJECT_UNLOCK (pad);
3534 return GST_FLOW_NOT_LINKED;
3538 gst_buffer_unref (buffer);
3539 gst_object_unref (peer);
3540 GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
3541 "element pushed buffer then refused to accept the caps");
3542 return GST_FLOW_NOT_NEGOTIATED;
3547 * gst_pad_check_pull_range:
3548 * @pad: a sink #GstPad.
3550 * Checks if a gst_pad_pull_range() can be performed on the peer
3551 * source pad. This function is used by plugins that want to check
3552 * if they can use random access on the peer source pad.
3554 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
3555 * if it needs to perform some logic to determine if pull_range is
3558 * Returns: a gboolean with the result.
3563 gst_pad_check_pull_range (GstPad * pad)
3567 GstPadCheckGetRangeFunction checkgetrangefunc;
3569 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3571 GST_OBJECT_LOCK (pad);
3572 if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
3573 goto wrong_direction;
3575 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3578 gst_object_ref (peer);
3579 GST_OBJECT_UNLOCK (pad);
3581 /* see note in above function */
3582 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
3583 /* FIXME, kindoff ghetto */
3584 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
3586 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3587 "calling checkgetrangefunc %s of peer pad %s:%s",
3588 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
3590 ret = checkgetrangefunc (peer);
3593 gst_object_unref (peer);
3597 /* ERROR recovery here */
3600 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3601 "checking pull range, but pad must be a sinkpad");
3602 GST_OBJECT_UNLOCK (pad);
3607 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3608 "checking pull range, but it was not linked");
3609 GST_OBJECT_UNLOCK (pad);
3615 * gst_pad_get_range:
3616 * @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
3617 * @offset: The start offset of the buffer
3618 * @size: The length of the buffer
3619 * @buffer: a pointer to hold the #GstBuffer, returns #GST_FLOW_ERROR if %NULL.
3621 * When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
3624 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
3625 * description of a getrange function. If @pad has no getrange function
3626 * installed (see gst_pad_set_getrange_function()) this function returns
3627 * #GST_FLOW_NOT_SUPPORTED.
3629 * Returns: a #GstFlowReturn from the pad.
3634 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
3635 GstBuffer ** buffer)
3638 GstPadGetRangeFunction getrangefunc;
3639 gboolean emit_signal;
3641 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3642 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3643 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3645 GST_PAD_STREAM_LOCK (pad);
3647 GST_OBJECT_LOCK (pad);
3648 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3651 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3652 GST_OBJECT_UNLOCK (pad);
3654 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
3657 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3658 "calling getrangefunc %s, offset %"
3659 G_GUINT64_FORMAT ", size %u",
3660 GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
3662 ret = getrangefunc (pad, offset, size, buffer);
3664 /* can only fire the signal if we have a valid buffer */
3665 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3666 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3670 GST_PAD_STREAM_UNLOCK (pad);
3677 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3678 "pulling range, but pad was flushing");
3679 GST_OBJECT_UNLOCK (pad);
3680 GST_PAD_STREAM_UNLOCK (pad);
3681 return GST_FLOW_WRONG_STATE;
3685 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3686 ("pullrange on pad %s:%s but it has no getrangefunction",
3687 GST_DEBUG_PAD_NAME (pad)));
3688 GST_PAD_STREAM_UNLOCK (pad);
3689 return GST_FLOW_NOT_SUPPORTED;
3693 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3694 "Dropping data after FALSE probe return");
3695 GST_PAD_STREAM_UNLOCK (pad);
3696 gst_buffer_unref (*buffer);
3698 return GST_FLOW_UNEXPECTED;
3704 * gst_pad_pull_range:
3705 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3706 * @offset: The start offset of the buffer
3707 * @size: The length of the buffer
3708 * @buffer: a pointer to hold the #GstBuffer, returns GST_FLOW_ERROR if %NULL.
3710 * Pulls a buffer from the peer pad.
3712 * This function will first trigger the pad block signal if it was
3715 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
3716 * function returns the result of gst_pad_get_range() on the peer pad.
3717 * See gst_pad_get_range() for a list of return values and for the
3718 * semantics of the arguments of this function.
3720 * Returns: a #GstFlowReturn from the peer pad.
3721 * When this function returns #GST_FLOW_OK, @buffer will contain a valid
3722 * #GstBuffer that should be freed with gst_buffer_unref() after usage.
3723 * @buffer may not be used or freed when any other return value than
3724 * #GST_FLOW_OK is returned.
3729 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
3730 GstBuffer ** buffer)
3734 gboolean emit_signal;
3736 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3737 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3739 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3741 GST_OBJECT_LOCK (pad);
3743 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3744 handle_pad_block (pad);
3746 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3749 /* signal emision for the pad, peer has chance to emit when
3750 * we call _get_range() */
3751 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3753 gst_object_ref (peer);
3754 GST_OBJECT_UNLOCK (pad);
3756 ret = gst_pad_get_range (peer, offset, size, buffer);
3758 gst_object_unref (peer);
3760 /* can only fire the signal if we have a valid buffer */
3761 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3762 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3767 /* ERROR recovery here */
3770 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3771 "pulling range, but it was not linked");
3772 GST_OBJECT_UNLOCK (pad);
3773 return GST_FLOW_NOT_LINKED;
3777 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3778 "Dropping data after FALSE probe return");
3779 gst_buffer_unref (*buffer);
3781 return GST_FLOW_UNEXPECTED;
3786 * gst_pad_push_event:
3787 * @pad: a #GstPad to push the event to.
3788 * @event: the #GstEvent to send to the pad.
3790 * Sends the event to the peer of the given pad. This function is
3791 * mainly used by elements to send events to their peer
3794 * This function takes owership of the provided event so you should
3795 * gst_event_ref() it if you want to reuse the event after this call.
3797 * Returns: TRUE if the event was handled.
3802 gst_pad_push_event (GstPad * pad, GstEvent * event)
3807 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3808 g_return_val_if_fail (event != NULL, FALSE);
3809 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
3811 GST_LOG_OBJECT (pad, "event:%s", GST_EVENT_TYPE_NAME (event));
3813 GST_OBJECT_LOCK (pad);
3815 /* Two checks to be made:
3816 * . (un)set the FLUSHING flag for flushing events,
3817 * . handle pad blocking */
3818 switch (GST_EVENT_TYPE (event)) {
3819 case GST_EVENT_FLUSH_START:
3820 GST_PAD_SET_FLUSHING (pad);
3822 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3823 /* flush start will have set the FLUSHING flag and will then
3824 * unlock all threads doing a GCond wait on the blocked pad. This
3825 * will typically unblock the STREAMING thread blocked on a pad. */
3826 GST_PAD_BLOCK_SIGNAL (pad);
3830 case GST_EVENT_FLUSH_STOP:
3831 GST_PAD_UNSET_FLUSHING (pad);
3833 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3837 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3838 if (GST_PAD_IS_FLUSHING (pad))
3840 while (GST_PAD_IS_BLOCKED (pad))
3841 /* else block the event as long as the pad is blocked */
3842 if (handle_pad_block (pad) != GST_FLOW_OK)
3848 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3849 GST_OBJECT_UNLOCK (pad);
3851 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3854 GST_OBJECT_LOCK (pad);
3856 peerpad = GST_PAD_PEER (pad);
3857 if (peerpad == NULL)
3860 GST_LOG_OBJECT (peerpad, "sending event on peerpad");
3861 gst_object_ref (peerpad);
3862 GST_OBJECT_UNLOCK (pad);
3864 result = gst_pad_send_event (peerpad, event);
3866 gst_object_unref (peerpad);
3867 GST_LOG_OBJECT (peerpad, "sent event on peerpad");
3871 /* ERROR handling */
3874 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
3875 gst_event_unref (event);
3880 GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
3881 gst_event_unref (event);
3882 GST_OBJECT_UNLOCK (pad);
3888 GST_DEBUG_OBJECT (pad,
3889 "Not forwarding event since we're flushing and blocking");
3890 gst_event_unref (event);
3891 GST_OBJECT_UNLOCK (pad);
3897 * gst_pad_send_event:
3898 * @pad: a #GstPad to send the event to.
3899 * @event: the #GstEvent to send to the pad.
3901 * Sends the event to the pad. This function can be used
3902 * by applications to send events in the pipeline.
3904 * If @pad is a source pad, @event should be an upstream event. If @pad is a
3905 * sink pad, @event should be a downstream event. For example, you would not
3906 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
3907 * Furthermore, some downstream events have to be serialized with data flow,
3908 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
3909 * the event needs to be serialized with data flow, this function will take the
3910 * pad's stream lock while calling its event function.
3912 * To find out whether an event type is upstream, downstream, or downstream and
3913 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
3914 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
3915 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or plugin
3916 * doesn't need to bother itself with this information; the core handles all
3917 * necessary locks and checks.
3919 * This function takes owership of the provided event so you should
3920 * gst_event_ref() it if you want to reuse the event after this call.
3922 * Returns: TRUE if the event was handled.
3925 gst_pad_send_event (GstPad * pad, GstEvent * event)
3927 gboolean result = FALSE;
3928 GstPadEventFunction eventfunc;
3929 gboolean serialized, need_unlock = FALSE;
3931 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3932 g_return_val_if_fail (event != NULL, FALSE);
3934 GST_OBJECT_LOCK (pad);
3935 if (GST_PAD_IS_SINK (pad)) {
3936 if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
3937 goto wrong_direction;
3938 serialized = GST_EVENT_IS_SERIALIZED (event);
3939 } else if (GST_PAD_IS_SRC (pad)) {
3940 if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
3941 goto wrong_direction;
3942 /* events on srcpad never are serialized */
3945 goto unknown_direction;
3947 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
3948 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
3949 GST_EVENT_SRC (event) = gst_object_ref (pad);
3953 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3954 GST_OBJECT_UNLOCK (pad);
3956 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
3959 GST_OBJECT_LOCK (pad);
3962 switch (GST_EVENT_TYPE (event)) {
3963 case GST_EVENT_FLUSH_START:
3964 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
3965 "have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
3967 /* can't even accept a flush begin event when flushing */
3968 if (GST_PAD_IS_FLUSHING (pad))
3970 GST_PAD_SET_FLUSHING (pad);
3971 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
3973 case GST_EVENT_FLUSH_STOP:
3974 GST_PAD_UNSET_FLUSHING (pad);
3975 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
3976 GST_OBJECT_UNLOCK (pad);
3977 /* grab stream lock */
3978 GST_PAD_STREAM_LOCK (pad);
3980 GST_OBJECT_LOCK (pad);
3983 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
3984 GST_EVENT_TYPE_NAME (event));
3986 /* make this a little faster, no point in grabbing the lock
3987 * if the pad is allready flushing. */
3988 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3992 /* lock order: STREAM_LOCK, LOCK */
3993 GST_OBJECT_UNLOCK (pad);
3994 GST_PAD_STREAM_LOCK (pad);
3996 GST_OBJECT_LOCK (pad);
3997 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4002 if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
4005 GST_OBJECT_UNLOCK (pad);
4007 result = eventfunc (pad, event);
4010 GST_PAD_STREAM_UNLOCK (pad);
4014 /* ERROR handling */
4017 g_warning ("pad %s:%s sending %s event in wrong direction",
4018 GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
4019 GST_OBJECT_UNLOCK (pad);
4020 gst_event_unref (event);
4025 g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
4026 GST_OBJECT_UNLOCK (pad);
4027 gst_event_unref (event);
4032 g_warning ("pad %s:%s has no event handler, file a bug.",
4033 GST_DEBUG_PAD_NAME (pad));
4034 GST_OBJECT_UNLOCK (pad);
4035 gst_event_unref (event);
4040 GST_OBJECT_UNLOCK (pad);
4042 GST_PAD_STREAM_UNLOCK (pad);
4043 GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
4044 "Received event on flushing pad. Discarding");
4045 gst_event_unref (event);
4050 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
4051 gst_event_unref (event);
4057 * gst_pad_set_element_private:
4058 * @pad: the #GstPad to set the private data of.
4059 * @priv: The private data to attach to the pad.
4061 * Set the given private data gpointer on the pad.
4062 * This function can only be used by the element that owns the pad.
4063 * No locking is performed in this function.
4066 gst_pad_set_element_private (GstPad * pad, gpointer priv)
4068 pad->element_private = priv;
4072 * gst_pad_get_element_private:
4073 * @pad: the #GstPad to get the private data of.
4075 * Gets the private data of a pad.
4076 * No locking is performed in this function.
4078 * Returns: a #gpointer to the private data.
4081 gst_pad_get_element_private (GstPad * pad)
4083 return pad->element_private;
4087 * gst_pad_start_task:
4088 * @pad: the #GstPad to start the task of
4089 * @func: the task function to call
4090 * @data: data passed to the task function
4092 * Starts a task that repeadedly calls @func with @data. This function
4093 * is nostly used in the pad activation function to start the
4094 * dataflow. This function will automatically acquire the STREAM_LOCK of
4095 * the pad before calling @func.
4097 * Returns: a TRUE if the task could be started.
4100 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
4104 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4105 g_return_val_if_fail (func != NULL, FALSE);
4107 GST_DEBUG_OBJECT (pad, "start task");
4109 GST_OBJECT_LOCK (pad);
4110 task = GST_PAD_TASK (pad);
4112 task = gst_task_create (func, data);
4113 gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
4114 GST_PAD_TASK (pad) = task;
4115 GST_DEBUG_OBJECT (pad, "created task");
4117 gst_task_start (task);
4118 GST_OBJECT_UNLOCK (pad);
4124 * gst_pad_pause_task:
4125 * @pad: the #GstPad to pause the task of
4127 * Pause the task of @pad. This function will also make sure that the
4128 * function executed by the task will effectively stop.
4130 * Returns: a TRUE if the task could be paused or FALSE when the pad
4134 gst_pad_pause_task (GstPad * pad)
4138 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4140 GST_DEBUG_OBJECT (pad, "pause task");
4142 GST_OBJECT_LOCK (pad);
4143 task = GST_PAD_TASK (pad);
4146 gst_task_pause (task);
4147 GST_OBJECT_UNLOCK (pad);
4149 GST_PAD_STREAM_LOCK (pad);
4150 GST_PAD_STREAM_UNLOCK (pad);
4156 GST_DEBUG_OBJECT (pad, "pad has no task");
4157 GST_OBJECT_UNLOCK (pad);
4163 * gst_pad_stop_task:
4164 * @pad: the #GstPad to stop the task of
4166 * Stop the task of @pad. This function will also make sure that the
4167 * function executed by the task will effectively stop if not called
4168 * from the GstTaskFunction.
4170 * This function will deadlock if called from the GstTaskFunction of
4171 * the task. Use gst_task_pause() instead.
4173 * Regardless of whether the pad has a task, the stream lock is acquired and
4174 * released so as to ensure that streaming through this pad has finished.
4176 * Returns: a TRUE if the task could be stopped or FALSE on error.
4179 gst_pad_stop_task (GstPad * pad)
4183 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4185 GST_DEBUG_OBJECT (pad, "stop task");
4187 GST_OBJECT_LOCK (pad);
4188 task = GST_PAD_TASK (pad);
4191 GST_PAD_TASK (pad) = NULL;
4192 gst_task_stop (task);
4193 GST_OBJECT_UNLOCK (pad);
4195 GST_PAD_STREAM_LOCK (pad);
4196 GST_PAD_STREAM_UNLOCK (pad);
4198 if (!gst_task_join (task))
4201 gst_object_unref (task);
4207 GST_DEBUG_OBJECT (pad, "no task");
4208 GST_OBJECT_UNLOCK (pad);
4210 GST_PAD_STREAM_LOCK (pad);
4211 GST_PAD_STREAM_UNLOCK (pad);
4213 /* this is not an error */
4218 /* this is bad, possibly the application tried to join the task from
4219 * the task's thread. We install the task again so that it will be stopped
4220 * again from the right thread next time hopefully. */
4221 GST_OBJECT_LOCK (pad);
4222 GST_DEBUG_OBJECT (pad, "join failed");
4223 /* we can only install this task if there was no other task */
4224 if (GST_PAD_TASK (pad) == NULL)
4225 GST_PAD_TASK (pad) = task;
4226 GST_OBJECT_UNLOCK (pad);