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 #define GST_PAD_GET_PRIVATE(obj) \
99 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PAD, GstPadPrivate))
101 #define GST_PAD_CHAINLISTFUNC(pad) ((pad)->abidata.ABI.priv->chainlistfunc)
103 struct _GstPadPrivate
105 GstPadChainListFunction chainlistfunc;
108 static void gst_pad_dispose (GObject * object);
109 static void gst_pad_finalize (GObject * object);
110 static void gst_pad_set_property (GObject * object, guint prop_id,
111 const GValue * value, GParamSpec * pspec);
112 static void gst_pad_get_property (GObject * object, guint prop_id,
113 GValue * value, GParamSpec * pspec);
115 static GstFlowReturn handle_pad_block (GstPad * pad);
116 static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
117 static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
118 static gboolean gst_pad_activate_default (GstPad * pad);
119 static gboolean gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps);
121 #ifndef GST_DISABLE_LOADSAVE
122 static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
125 /* Some deprecated stuff that we need inside here for
126 * backwards compatibility */
127 #ifdef GST_DISABLE_DEPRECATED
128 #ifndef GST_REMOVE_DEPRECATED
129 #define GST_PAD_INTLINKFUNC(pad) (GST_PAD_CAST(pad)->intlinkfunc)
130 GList *gst_pad_get_internal_links_default (GstPad * pad);
134 static GstObjectClass *parent_class = NULL;
135 static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
137 /* quarks for probe signals */
138 static GQuark buffer_quark;
139 static GQuark event_quark;
148 static GstFlowQuarks flow_quarks[] = {
149 {GST_FLOW_CUSTOM_SUCCESS, "custom-success", 0},
150 {GST_FLOW_RESEND, "resend", 0},
151 {GST_FLOW_OK, "ok", 0},
152 {GST_FLOW_NOT_LINKED, "not-linked", 0},
153 {GST_FLOW_WRONG_STATE, "wrong-state", 0},
154 {GST_FLOW_UNEXPECTED, "unexpected", 0},
155 {GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
156 {GST_FLOW_ERROR, "error", 0},
157 {GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
158 {GST_FLOW_CUSTOM_ERROR, "custom-error", 0}
163 * @ret: a #GstFlowReturn to get the name of.
165 * Gets a string representing the given flow return.
167 * Returns: a static string with the name of the flow return.
169 G_CONST_RETURN gchar *
170 gst_flow_get_name (GstFlowReturn ret)
174 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
176 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
177 if (ret == flow_quarks[i].ret)
178 return flow_quarks[i].name;
185 * @ret: a #GstFlowReturn to get the quark of.
187 * Get the unique quark for the given GstFlowReturn.
189 * Returns: the quark associated with the flow return or 0 if an
190 * invalid return was specified.
193 gst_flow_to_quark (GstFlowReturn ret)
197 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
199 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
200 if (ret == flow_quarks[i].ret)
201 return flow_quarks[i].quark;
210 buffer_quark = g_quark_from_static_string ("buffer"); \
211 event_quark = g_quark_from_static_string ("event"); \
213 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) { \
214 flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name); \
217 GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW", \
218 GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads"); \
221 G_DEFINE_TYPE_WITH_CODE (GstPad, gst_pad, GST_TYPE_OBJECT, _do_init);
224 _gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
225 GValue * return_accu, const GValue * handler_return, gpointer dummy)
227 gboolean ret = g_value_get_boolean (handler_return);
229 GST_DEBUG ("accumulated %d", ret);
230 g_value_set_boolean (return_accu, ret);
236 default_have_data (GstPad * pad, GstMiniObject * o)
242 gst_pad_class_init (GstPadClass * klass)
244 GObjectClass *gobject_class;
245 GstObjectClass *gstobject_class;
247 gobject_class = G_OBJECT_CLASS (klass);
248 gstobject_class = GST_OBJECT_CLASS (klass);
250 g_type_class_add_private (klass, sizeof (GstPadPrivate));
252 parent_class = g_type_class_peek_parent (klass);
254 gobject_class->dispose = gst_pad_dispose;
255 gobject_class->finalize = gst_pad_finalize;
256 gobject_class->set_property = gst_pad_set_property;
257 gobject_class->get_property = gst_pad_get_property;
261 * @pad: the pad that emitted the signal
262 * @peer: the peer pad that has been connected
264 * Signals that a pad has been linked to the peer pad.
266 gst_pad_signals[PAD_LINKED] =
267 g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
268 G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
269 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
272 * @pad: the pad that emitted the signal
273 * @peer: the peer pad that has been disconnected
275 * Signals that a pad has been unlinked from the peer pad.
277 gst_pad_signals[PAD_UNLINKED] =
278 g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
279 G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
280 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
282 * GstPad::request-link:
283 * @pad: the pad that emitted the signal
284 * @peer: the peer pad for which a connection is requested
286 * Signals that a pad connection has been requested.
288 gst_pad_signals[PAD_REQUEST_LINK] =
289 g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
290 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
291 NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
295 * @pad: the pad that emitted the signal
296 * @mini_obj: new data
298 * Signals that new data is available on the pad. This signal is used
299 * internally for implementing pad probes.
300 * See gst_pad_add_*_probe functions.
302 * Returns: %TRUE to keep the data, %FALSE to drop it
304 gst_pad_signals[PAD_HAVE_DATA] =
305 g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
306 G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
307 G_STRUCT_OFFSET (GstPadClass, have_data),
308 _gst_do_pass_data_accumulator,
309 NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
310 GST_TYPE_MINI_OBJECT);
312 g_object_class_install_property (gobject_class, PAD_PROP_CAPS,
313 g_param_spec_boxed ("caps", "Caps", "The capabilities of the pad",
314 GST_TYPE_CAPS, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
315 g_object_class_install_property (gobject_class, PAD_PROP_DIRECTION,
316 g_param_spec_enum ("direction", "Direction", "The direction of the pad",
317 GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
318 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
319 /* FIXME, Make G_PARAM_CONSTRUCT_ONLY when we fix ghostpads. */
320 g_object_class_install_property (gobject_class, PAD_PROP_TEMPLATE,
321 g_param_spec_object ("template", "Template",
322 "The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
323 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
325 #ifndef GST_DISABLE_LOADSAVE
326 gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_pad_save_thyself);
328 gstobject_class->path_string_separator = ".";
330 /* Register common function pointer descriptions */
331 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_activate_default);
332 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_event_default);
333 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_query_types_default);
334 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_query_default);
335 #ifndef GST_REMOVE_DEPRECATED
336 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_internal_links_default);
338 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_iterate_internal_links_default);
339 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_acceptcaps_default);
341 klass->have_data = default_have_data;
345 gst_pad_init (GstPad * pad)
347 pad->abidata.ABI.priv = GST_PAD_GET_PRIVATE (pad);
349 GST_PAD_DIRECTION (pad) = GST_PAD_UNKNOWN;
350 GST_PAD_PEER (pad) = NULL;
352 GST_PAD_CHAINFUNC (pad) = NULL;
354 GST_PAD_LINKFUNC (pad) = NULL;
356 GST_PAD_CAPS (pad) = NULL;
357 GST_PAD_GETCAPSFUNC (pad) = NULL;
359 GST_PAD_ACTIVATEFUNC (pad) = gst_pad_activate_default;
360 GST_PAD_EVENTFUNC (pad) = gst_pad_event_default;
361 GST_PAD_QUERYTYPEFUNC (pad) = gst_pad_get_query_types_default;
362 GST_PAD_QUERYFUNC (pad) = gst_pad_query_default;
363 #ifndef GST_REMOVE_DEPRECATED
364 GST_PAD_INTLINKFUNC (pad) = gst_pad_get_internal_links_default;
366 GST_PAD_ITERINTLINKFUNC (pad) = gst_pad_iterate_internal_links_default;
368 GST_PAD_ACCEPTCAPSFUNC (pad) = gst_pad_acceptcaps_default;
370 pad->do_buffer_signals = 0;
371 pad->do_event_signals = 0;
373 GST_PAD_SET_FLUSHING (pad);
375 pad->preroll_lock = g_mutex_new ();
376 pad->preroll_cond = g_cond_new ();
378 /* FIXME 0.11: Store this directly in the instance struct */
379 pad->stream_rec_lock = g_slice_new (GStaticRecMutex);
380 g_static_rec_mutex_init (pad->stream_rec_lock);
382 pad->block_cond = g_cond_new ();
386 gst_pad_dispose (GObject * object)
388 GstPad *pad = GST_PAD_CAST (object);
391 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pad, "dispose");
393 /* unlink the peer pad */
394 if ((peer = gst_pad_get_peer (pad))) {
395 /* window for MT unsafeness, someone else could unlink here
396 * and then we call unlink with wrong pads. The unlink
397 * function would catch this and safely return failed. */
398 if (GST_PAD_IS_SRC (pad))
399 gst_pad_unlink (pad, peer);
401 gst_pad_unlink (peer, pad);
403 gst_object_unref (peer);
407 gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
409 gst_pad_set_pad_template (pad, NULL);
411 if (pad->block_destroy_data && pad->block_data) {
412 pad->block_destroy_data (pad->block_data);
413 pad->block_data = NULL;
416 G_OBJECT_CLASS (parent_class)->dispose (object);
420 gst_pad_finalize (GObject * object)
422 GstPad *pad = GST_PAD_CAST (object);
425 /* in case the task is still around, clean it up */
426 if ((task = GST_PAD_TASK (pad))) {
427 gst_task_join (task);
428 GST_PAD_TASK (pad) = NULL;
429 gst_object_unref (task);
432 if (pad->stream_rec_lock) {
433 g_static_rec_mutex_free (pad->stream_rec_lock);
434 g_slice_free (GStaticRecMutex, pad->stream_rec_lock);
435 pad->stream_rec_lock = NULL;
437 if (pad->preroll_lock) {
438 g_mutex_free (pad->preroll_lock);
439 g_cond_free (pad->preroll_cond);
440 pad->preroll_lock = NULL;
441 pad->preroll_cond = NULL;
443 if (pad->block_cond) {
444 g_cond_free (pad->block_cond);
445 pad->block_cond = NULL;
448 G_OBJECT_CLASS (parent_class)->finalize (object);
452 gst_pad_set_property (GObject * object, guint prop_id,
453 const GValue * value, GParamSpec * pspec)
455 g_return_if_fail (GST_IS_PAD (object));
458 case PAD_PROP_DIRECTION:
459 GST_PAD_DIRECTION (object) = g_value_get_enum (value);
461 case PAD_PROP_TEMPLATE:
462 gst_pad_set_pad_template (GST_PAD_CAST (object),
463 (GstPadTemplate *) g_value_get_object (value));
466 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
472 gst_pad_get_property (GObject * object, guint prop_id,
473 GValue * value, GParamSpec * pspec)
475 g_return_if_fail (GST_IS_PAD (object));
479 GST_OBJECT_LOCK (object);
480 g_value_set_boxed (value, GST_PAD_CAPS (object));
481 GST_OBJECT_UNLOCK (object);
483 case PAD_PROP_DIRECTION:
484 g_value_set_enum (value, GST_PAD_DIRECTION (object));
486 case PAD_PROP_TEMPLATE:
487 g_value_set_object (value, GST_PAD_PAD_TEMPLATE (object));
490 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
497 * @name: the name of the new pad.
498 * @direction: the #GstPadDirection of the pad.
500 * Creates a new pad with the given name in the given direction.
501 * If name is NULL, a guaranteed unique name (across all pads)
503 * This function makes a copy of the name so you can safely free the name.
505 * Returns: a new #GstPad, or NULL in case of an error.
510 gst_pad_new (const gchar * name, GstPadDirection direction)
512 return g_object_new (GST_TYPE_PAD,
513 "name", name, "direction", direction, NULL);
517 * gst_pad_new_from_template:
518 * @templ: the pad template to use
519 * @name: the name of the element
521 * Creates a new pad with the given name from the given template.
522 * If name is NULL, a guaranteed unique name (across all pads)
524 * This function makes a copy of the name so you can safely free the name.
526 * Returns: a new #GstPad, or NULL in case of an error.
529 gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
531 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
533 return g_object_new (GST_TYPE_PAD,
534 "name", name, "direction", templ->direction, "template", templ, NULL);
538 * gst_pad_new_from_static_template:
539 * @templ: the #GstStaticPadTemplate to use
540 * @name: the name of the element
542 * Creates a new pad with the given name from the given static template.
543 * If name is NULL, a guaranteed unique name (across all pads)
545 * This function makes a copy of the name so you can safely free the name.
547 * Returns: a new #GstPad, or NULL in case of an error.
550 gst_pad_new_from_static_template (GstStaticPadTemplate * templ,
554 GstPadTemplate *template;
556 template = gst_static_pad_template_get (templ);
557 pad = gst_pad_new_from_template (template, name);
558 gst_object_unref (template);
563 * gst_pad_get_direction:
564 * @pad: a #GstPad to get the direction of.
566 * Gets the direction of the pad. The direction of the pad is
567 * decided at construction time so this function does not take
570 * Returns: the #GstPadDirection of the pad.
575 gst_pad_get_direction (GstPad * pad)
577 GstPadDirection result;
579 /* PAD_UNKNOWN is a little silly but we need some sort of
580 * error return value */
581 g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
583 result = GST_PAD_DIRECTION (pad);
589 gst_pad_activate_default (GstPad * pad)
591 return gst_pad_activate_push (pad, TRUE);
595 pre_activate (GstPad * pad, GstActivateMode new_mode)
598 case GST_ACTIVATE_PUSH:
599 case GST_ACTIVATE_PULL:
600 GST_OBJECT_LOCK (pad);
601 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d, unset flushing",
603 GST_PAD_UNSET_FLUSHING (pad);
604 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
605 GST_OBJECT_UNLOCK (pad);
607 case GST_ACTIVATE_NONE:
608 GST_OBJECT_LOCK (pad);
609 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE NONE, set flushing");
610 GST_PAD_SET_FLUSHING (pad);
611 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
612 /* unlock blocked pads so element can resume and stop */
613 GST_PAD_BLOCK_BROADCAST (pad);
614 GST_OBJECT_UNLOCK (pad);
620 post_activate (GstPad * pad, GstActivateMode new_mode)
623 case GST_ACTIVATE_PUSH:
624 case GST_ACTIVATE_PULL:
627 case GST_ACTIVATE_NONE:
628 /* ensures that streaming stops */
629 GST_PAD_STREAM_LOCK (pad);
630 GST_DEBUG_OBJECT (pad, "stopped streaming");
631 GST_PAD_STREAM_UNLOCK (pad);
637 * gst_pad_set_active:
638 * @pad: the #GstPad to activate or deactivate.
639 * @active: whether or not the pad should be active.
641 * Activates or deactivates the given pad.
642 * Normally called from within core state change functions.
644 * If @active, makes sure the pad is active. If it is already active, either in
645 * push or pull mode, just return. Otherwise dispatches to the pad's activate
646 * function to perform the actual activation.
648 * If not @active, checks the pad's current mode and calls
649 * gst_pad_activate_push() or gst_pad_activate_pull(), as appropriate, with a
652 * Returns: #TRUE if the operation was successful.
657 gst_pad_set_active (GstPad * pad, gboolean active)
660 gboolean ret = FALSE;
662 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
664 GST_OBJECT_LOCK (pad);
665 old = GST_PAD_ACTIVATE_MODE (pad);
666 GST_OBJECT_UNLOCK (pad);
670 case GST_ACTIVATE_PUSH:
671 GST_DEBUG_OBJECT (pad, "activating pad from push");
674 case GST_ACTIVATE_PULL:
675 GST_DEBUG_OBJECT (pad, "activating pad from pull");
678 case GST_ACTIVATE_NONE:
679 GST_DEBUG_OBJECT (pad, "activating pad from none");
680 ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
685 case GST_ACTIVATE_PUSH:
686 GST_DEBUG_OBJECT (pad, "deactivating pad from push");
687 ret = gst_pad_activate_push (pad, FALSE);
689 case GST_ACTIVATE_PULL:
690 GST_DEBUG_OBJECT (pad, "deactivating pad from pull");
691 ret = gst_pad_activate_pull (pad, FALSE);
693 case GST_ACTIVATE_NONE:
694 GST_DEBUG_OBJECT (pad, "deactivating pad from none");
701 GST_OBJECT_LOCK (pad);
703 g_critical ("Failed to deactivate pad %s:%s, very bad",
704 GST_DEBUG_PAD_NAME (pad));
706 GST_WARNING_OBJECT (pad, "Failed to activate pad");
708 GST_OBJECT_UNLOCK (pad);
715 * gst_pad_activate_pull:
716 * @pad: the #GstPad to activate or deactivate.
717 * @active: whether or not the pad should be active.
719 * Activates or deactivates the given pad in pull mode via dispatching to the
720 * pad's activatepullfunc. For use from within pad activation functions only.
721 * When called on sink pads, will first proxy the call to the peer pad, which
722 * is expected to activate its internally linked pads from within its
723 * activate_pull function.
725 * If you don't know what this is, you probably don't want to call it.
727 * Returns: TRUE if the operation was successful.
732 gst_pad_activate_pull (GstPad * pad, gboolean active)
734 GstActivateMode old, new;
737 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
739 GST_OBJECT_LOCK (pad);
740 old = GST_PAD_ACTIVATE_MODE (pad);
741 GST_OBJECT_UNLOCK (pad);
745 case GST_ACTIVATE_PULL:
746 GST_DEBUG_OBJECT (pad, "activating pad from pull, was ok");
748 case GST_ACTIVATE_PUSH:
749 GST_DEBUG_OBJECT (pad,
750 "activating pad from push, deactivate push first");
751 /* pad was activate in the wrong direction, deactivate it
752 * and reactivate it in pull mode */
753 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
754 goto deactivate_failed;
755 /* fallthrough, pad is deactivated now. */
756 case GST_ACTIVATE_NONE:
757 GST_DEBUG_OBJECT (pad, "activating pad from none");
762 case GST_ACTIVATE_NONE:
763 GST_DEBUG_OBJECT (pad, "deactivating pad from none, was ok");
765 case GST_ACTIVATE_PUSH:
766 GST_DEBUG_OBJECT (pad, "deactivating pad from push, weird");
767 /* pad was activated in the other direction, deactivate it
768 * in push mode, this should not happen... */
769 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
770 goto deactivate_failed;
771 /* everything is fine now */
773 case GST_ACTIVATE_PULL:
774 GST_DEBUG_OBJECT (pad, "deactivating pad from pull");
779 if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
780 if ((peer = gst_pad_get_peer (pad))) {
781 GST_DEBUG_OBJECT (pad, "calling peer");
782 if (G_UNLIKELY (!gst_pad_activate_pull (peer, active)))
784 gst_object_unref (peer);
786 /* there is no peer, this is only fatal when we activate. When we
787 * deactivate, we must assume the application has unlinked the peer and
788 * will deactivate it eventually. */
792 GST_DEBUG_OBJECT (pad, "deactivating unlinked pad");
795 if (G_UNLIKELY (GST_PAD_GETRANGEFUNC (pad) == NULL))
796 goto failure; /* Can't activate pull on a src without a
800 new = active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
801 pre_activate (pad, new);
803 if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
804 if (G_UNLIKELY (!GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active)))
807 /* can happen for sinks of passthrough elements */
810 post_activate (pad, new);
812 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
813 active ? "activated" : "deactivated");
819 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
820 active ? "activated" : "deactivated");
825 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
826 "failed to %s in switch to pull from mode %d",
827 (active ? "activate" : "deactivate"), old);
832 GST_OBJECT_LOCK (peer);
833 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
834 "activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
835 GST_OBJECT_UNLOCK (peer);
836 gst_object_unref (peer);
841 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "can't activate unlinked sink "
847 GST_OBJECT_LOCK (pad);
848 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
849 active ? "activate" : "deactivate");
850 GST_PAD_SET_FLUSHING (pad);
851 GST_PAD_ACTIVATE_MODE (pad) = old;
852 GST_OBJECT_UNLOCK (pad);
858 * gst_pad_activate_push:
859 * @pad: the #GstPad to activate or deactivate.
860 * @active: whether the pad should be active or not.
862 * Activates or deactivates the given pad in push mode via dispatching to the
863 * pad's activatepushfunc. For use from within pad activation functions only.
865 * If you don't know what this is, you probably don't want to call it.
867 * Returns: %TRUE if the operation was successful.
872 gst_pad_activate_push (GstPad * pad, gboolean active)
874 GstActivateMode old, new;
876 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
877 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
878 active ? "activated" : "deactivated");
880 GST_OBJECT_LOCK (pad);
881 old = GST_PAD_ACTIVATE_MODE (pad);
882 GST_OBJECT_UNLOCK (pad);
886 case GST_ACTIVATE_PUSH:
887 GST_DEBUG_OBJECT (pad, "activating pad from push, was ok");
889 case GST_ACTIVATE_PULL:
890 GST_DEBUG_OBJECT (pad,
891 "activating pad from push, deactivating pull first");
892 /* pad was activate in the wrong direction, deactivate it
893 * an reactivate it in push mode */
894 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
895 goto deactivate_failed;
896 /* fallthrough, pad is deactivated now. */
897 case GST_ACTIVATE_NONE:
898 GST_DEBUG_OBJECT (pad, "activating pad from none");
903 case GST_ACTIVATE_NONE:
904 GST_DEBUG_OBJECT (pad, "deactivating pad from none, was ok");
906 case GST_ACTIVATE_PULL:
907 GST_DEBUG_OBJECT (pad, "deactivating pad from pull, weird");
908 /* pad was activated in the other direction, deactivate it
909 * in pull mode, this should not happen... */
910 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
911 goto deactivate_failed;
912 /* everything is fine now */
914 case GST_ACTIVATE_PUSH:
915 GST_DEBUG_OBJECT (pad, "deactivating pad from push");
920 new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
921 pre_activate (pad, new);
923 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
924 if (G_UNLIKELY (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active))) {
928 /* quite ok, element relies on state change func to prepare itself */
931 post_activate (pad, new);
933 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
934 active ? "activated" : "deactivated");
939 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
940 active ? "activated" : "deactivated");
945 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
946 "failed to %s in switch to push from mode %d",
947 (active ? "activate" : "deactivate"), old);
952 GST_OBJECT_LOCK (pad);
953 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
954 active ? "activate" : "deactivate");
955 GST_PAD_SET_FLUSHING (pad);
956 GST_PAD_ACTIVATE_MODE (pad) = old;
957 GST_OBJECT_UNLOCK (pad);
964 * @pad: the #GstPad to query
966 * Query if a pad is active
968 * Returns: TRUE if the pad is active.
973 gst_pad_is_active (GstPad * pad)
975 gboolean result = FALSE;
977 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
979 GST_OBJECT_LOCK (pad);
980 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
981 GST_OBJECT_UNLOCK (pad);
987 * gst_pad_set_blocked_async_full:
988 * @pad: the #GstPad to block or unblock
989 * @blocked: boolean indicating whether the pad should be blocked or unblocked
990 * @callback: #GstPadBlockCallback that will be called when the
992 * @user_data: user data passed to the callback
993 * @destroy_data: #GDestroyNotify for user_data
995 * Blocks or unblocks the dataflow on a pad. The provided callback
996 * is called when the operation succeeds; this happens right before the next
997 * attempt at pushing a buffer on the pad.
999 * This can take a while as the pad can only become blocked when real dataflow
1001 * When the pipeline is stalled, for example in PAUSED, this can
1002 * take an indeterminate amount of time.
1003 * You can pass NULL as the callback to make this call block. Be careful with
1004 * this blocking call as it might not return for reasons stated above.
1006 * Returns: TRUE if the pad could be blocked. This function can fail if the
1007 * wrong parameters were passed or the pad was already in the requested state.
1014 gst_pad_set_blocked_async_full (GstPad * pad, gboolean blocked,
1015 GstPadBlockCallback callback, gpointer user_data,
1016 GDestroyNotify destroy_data)
1018 gboolean was_blocked = FALSE;
1020 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1022 GST_OBJECT_LOCK (pad);
1024 was_blocked = GST_PAD_IS_BLOCKED (pad);
1026 if (G_UNLIKELY (was_blocked == blocked))
1027 goto had_right_state;
1030 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
1032 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
1034 if (pad->block_destroy_data && pad->block_data)
1035 pad->block_destroy_data (pad->block_data);
1037 pad->block_callback = callback;
1038 pad->block_data = user_data;
1039 pad->block_destroy_data = destroy_data;
1040 pad->abidata.ABI.block_callback_called = FALSE;
1042 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
1043 GST_PAD_BLOCK_WAIT (pad);
1044 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
1047 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
1049 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
1051 if (pad->block_destroy_data && pad->block_data)
1052 pad->block_destroy_data (pad->block_data);
1054 pad->block_callback = callback;
1055 pad->block_data = user_data;
1056 pad->block_destroy_data = destroy_data;
1057 pad->abidata.ABI.block_callback_called = FALSE;
1059 GST_PAD_BLOCK_BROADCAST (pad);
1061 /* no callback, wait for the unblock to happen */
1062 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
1063 GST_PAD_BLOCK_WAIT (pad);
1064 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
1067 GST_OBJECT_UNLOCK (pad);
1073 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
1074 "pad was in right state (%d)", was_blocked);
1075 GST_OBJECT_UNLOCK (pad);
1082 * gst_pad_set_blocked_async:
1083 * @pad: the #GstPad to block or unblock
1084 * @blocked: boolean indicating whether the pad should be blocked or unblocked
1085 * @callback: #GstPadBlockCallback that will be called when the
1086 * operation succeeds
1087 * @user_data: user data passed to the callback
1089 * Blocks or unblocks the dataflow on a pad. The provided callback
1090 * is called when the operation succeeds; this happens right before the next
1091 * attempt at pushing a buffer on the pad.
1093 * This can take a while as the pad can only become blocked when real dataflow
1095 * When the pipeline is stalled, for example in PAUSED, this can
1096 * take an indeterminate amount of time.
1097 * You can pass NULL as the callback to make this call block. Be careful with
1098 * this blocking call as it might not return for reasons stated above.
1100 * Returns: TRUE if the pad could be blocked. This function can fail if the
1101 * wrong parameters were passed or the pad was already in the requested state.
1106 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
1107 GstPadBlockCallback callback, gpointer user_data)
1109 return gst_pad_set_blocked_async_full (pad, blocked,
1110 callback, user_data, NULL);
1114 * gst_pad_set_blocked:
1115 * @pad: the #GstPad to block or unblock
1116 * @blocked: boolean indicating we should block or unblock
1118 * Blocks or unblocks the dataflow on a pad. This function is
1119 * a shortcut for gst_pad_set_blocked_async() with a NULL
1122 * Returns: TRUE if the pad could be blocked. This function can fail if the
1123 * wrong parameters were passed or the pad was already in the requested state.
1128 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
1130 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
1134 * gst_pad_is_blocked:
1135 * @pad: the #GstPad to query
1137 * Checks if the pad is blocked or not. This function returns the
1138 * last requested state of the pad. It is not certain that the pad
1139 * is actually blocking at this point (see gst_pad_is_blocking()).
1141 * Returns: TRUE if the pad is blocked.
1146 gst_pad_is_blocked (GstPad * pad)
1148 gboolean result = FALSE;
1150 g_return_val_if_fail (GST_IS_PAD (pad), result);
1152 GST_OBJECT_LOCK (pad);
1153 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
1154 GST_OBJECT_UNLOCK (pad);
1160 * gst_pad_is_blocking:
1161 * @pad: the #GstPad to query
1163 * Checks if the pad is blocking or not. This is a guaranteed state
1164 * of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
1166 * Returns: TRUE if the pad is blocking.
1173 gst_pad_is_blocking (GstPad * pad)
1175 gboolean result = FALSE;
1177 g_return_val_if_fail (GST_IS_PAD (pad), result);
1179 GST_OBJECT_LOCK (pad);
1180 /* the blocking flag is only valid if the pad is not flushing */
1181 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKING) &&
1182 !GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLUSHING);
1183 GST_OBJECT_UNLOCK (pad);
1189 * gst_pad_set_activate_function:
1191 * @activate: the #GstPadActivateFunction to set.
1193 * Sets the given activate function for @pad. The activate function will
1194 * dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
1195 * the actual activation. Only makes sense to set on sink pads.
1197 * Call this function if your sink pad can start a pull-based task.
1200 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
1202 g_return_if_fail (GST_IS_PAD (pad));
1204 GST_PAD_ACTIVATEFUNC (pad) = activate;
1205 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
1206 GST_DEBUG_FUNCPTR_NAME (activate));
1210 * gst_pad_set_activatepull_function:
1212 * @activatepull: the #GstPadActivateModeFunction to set.
1214 * Sets the given activate_pull function for the pad. An activate_pull function
1215 * prepares the element and any upstream connections for pulling. See XXX
1216 * part-activation.txt for details.
1219 gst_pad_set_activatepull_function (GstPad * pad,
1220 GstPadActivateModeFunction activatepull)
1222 g_return_if_fail (GST_IS_PAD (pad));
1224 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
1225 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
1226 GST_DEBUG_FUNCPTR_NAME (activatepull));
1230 * gst_pad_set_activatepush_function:
1232 * @activatepush: the #GstPadActivateModeFunction to set.
1234 * Sets the given activate_push function for the pad. An activate_push function
1235 * prepares the element for pushing. See XXX part-activation.txt for details.
1238 gst_pad_set_activatepush_function (GstPad * pad,
1239 GstPadActivateModeFunction activatepush)
1241 g_return_if_fail (GST_IS_PAD (pad));
1243 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1244 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
1245 GST_DEBUG_FUNCPTR_NAME (activatepush));
1249 * gst_pad_set_chain_function:
1250 * @pad: a sink #GstPad.
1251 * @chain: the #GstPadChainFunction to set.
1253 * Sets the given chain function for the pad. The chain function is called to
1254 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1257 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1259 g_return_if_fail (GST_IS_PAD (pad));
1260 g_return_if_fail (GST_PAD_IS_SINK (pad));
1262 GST_PAD_CHAINFUNC (pad) = chain;
1263 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
1264 GST_DEBUG_FUNCPTR_NAME (chain));
1268 * gst_pad_set_chain_list_function:
1269 * @pad: a sink #GstPad.
1270 * @chainlist: the #GstPadChainListFunction to set.
1272 * Sets the given chain list function for the pad. The chainlist function is
1273 * called to process a #GstBufferList input buffer list. See
1274 * #GstPadChainListFunction for more details.
1279 gst_pad_set_chain_list_function (GstPad * pad,
1280 GstPadChainListFunction chainlist)
1282 g_return_if_fail (GST_IS_PAD (pad));
1283 g_return_if_fail (GST_PAD_IS_SINK (pad));
1285 GST_PAD_CHAINLISTFUNC (pad) = chainlist;
1286 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainlistfunc set to %s",
1287 GST_DEBUG_FUNCPTR_NAME (chainlist));
1291 * gst_pad_set_getrange_function:
1292 * @pad: a source #GstPad.
1293 * @get: the #GstPadGetRangeFunction to set.
1295 * Sets the given getrange function for the pad. The getrange function is
1296 * called to produce a new #GstBuffer to start the processing pipeline. see
1297 * #GstPadGetRangeFunction for a description of the getrange function.
1300 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1302 g_return_if_fail (GST_IS_PAD (pad));
1303 g_return_if_fail (GST_PAD_IS_SRC (pad));
1305 GST_PAD_GETRANGEFUNC (pad) = get;
1307 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
1308 GST_DEBUG_FUNCPTR_NAME (get));
1312 * gst_pad_set_checkgetrange_function:
1313 * @pad: a source #GstPad.
1314 * @check: the #GstPadCheckGetRangeFunction to set.
1316 * Sets the given checkgetrange function for the pad. Implement this function
1317 * on a pad if you dynamically support getrange based scheduling on the pad.
1320 gst_pad_set_checkgetrange_function (GstPad * pad,
1321 GstPadCheckGetRangeFunction check)
1323 g_return_if_fail (GST_IS_PAD (pad));
1324 g_return_if_fail (GST_PAD_IS_SRC (pad));
1326 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1328 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
1329 GST_DEBUG_FUNCPTR_NAME (check));
1333 * gst_pad_set_event_function:
1334 * @pad: a #GstPad of either direction.
1335 * @event: the #GstPadEventFunction to set.
1337 * Sets the given event handler for the pad.
1340 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1342 g_return_if_fail (GST_IS_PAD (pad));
1344 GST_PAD_EVENTFUNC (pad) = event;
1346 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
1347 GST_DEBUG_FUNCPTR_NAME (event));
1351 * gst_pad_set_query_function:
1352 * @pad: a #GstPad of either direction.
1353 * @query: the #GstPadQueryFunction to set.
1355 * Set the given query function for the pad.
1358 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1360 g_return_if_fail (GST_IS_PAD (pad));
1362 GST_PAD_QUERYFUNC (pad) = query;
1364 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
1365 GST_DEBUG_FUNCPTR_NAME (query));
1369 * gst_pad_set_query_type_function:
1370 * @pad: a #GstPad of either direction.
1371 * @type_func: the #GstPadQueryTypeFunction to set.
1373 * Set the given query type function for the pad.
1376 gst_pad_set_query_type_function (GstPad * pad,
1377 GstPadQueryTypeFunction type_func)
1379 g_return_if_fail (GST_IS_PAD (pad));
1381 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1383 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
1384 GST_DEBUG_FUNCPTR_NAME (type_func));
1388 * gst_pad_get_query_types:
1391 * Get an array of supported queries that can be performed
1394 * Returns: a zero-terminated array of #GstQueryType.
1396 const GstQueryType *
1397 gst_pad_get_query_types (GstPad * pad)
1399 GstPadQueryTypeFunction func;
1401 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1403 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1415 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1417 *data = gst_pad_get_query_types (pad);
1423 * gst_pad_get_query_types_default:
1426 * Invoke the default dispatcher for the query types on
1429 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1430 * internally-linked pads has a query types function.
1432 const GstQueryType *
1433 gst_pad_get_query_types_default (GstPad * pad)
1435 GstQueryType *result = NULL;
1437 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1439 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1440 gst_pad_get_query_types_dispatcher, &result);
1446 * gst_pad_set_iterate_internal_links_function:
1447 * @pad: a #GstPad of either direction.
1448 * @iterintlink: the #GstPadIterIntLinkFunction to set.
1450 * Sets the given internal link iterator function for the pad.
1455 gst_pad_set_iterate_internal_links_function (GstPad * pad,
1456 GstPadIterIntLinkFunction iterintlink)
1458 g_return_if_fail (GST_IS_PAD (pad));
1460 GST_PAD_ITERINTLINKFUNC (pad) = iterintlink;
1461 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link iterator set to %s",
1462 GST_DEBUG_FUNCPTR_NAME (iterintlink));
1466 * gst_pad_set_internal_link_function:
1467 * @pad: a #GstPad of either direction.
1468 * @intlink: the #GstPadIntLinkFunction to set.
1470 * Sets the given internal link function for the pad.
1472 * Deprecated: Use the thread-safe gst_pad_set_iterate_internal_links_function()
1474 #ifndef GST_REMOVE_DEPRECATED
1475 #ifdef GST_DISABLE_DEPRECATED
1477 gst_pad_set_internal_link_function (GstPad * pad,
1478 GstPadIntLinkFunction intlink);
1481 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1483 g_return_if_fail (GST_IS_PAD (pad));
1485 GST_PAD_INTLINKFUNC (pad) = intlink;
1486 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
1487 GST_DEBUG_FUNCPTR_NAME (intlink));
1489 #endif /* GST_REMOVE_DEPRECATED */
1492 * gst_pad_set_link_function:
1494 * @link: the #GstPadLinkFunction to set.
1496 * Sets the given link function for the pad. It will be called when
1497 * the pad is linked with another pad.
1499 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1502 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1503 * cannot be made for some reason.
1505 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1506 * of the peer sink pad, if present.
1509 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1511 g_return_if_fail (GST_IS_PAD (pad));
1513 GST_PAD_LINKFUNC (pad) = link;
1514 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
1515 GST_DEBUG_FUNCPTR_NAME (link));
1519 * gst_pad_set_unlink_function:
1521 * @unlink: the #GstPadUnlinkFunction to set.
1523 * Sets the given unlink function for the pad. It will be called
1524 * when the pad is unlinked.
1527 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1529 g_return_if_fail (GST_IS_PAD (pad));
1531 GST_PAD_UNLINKFUNC (pad) = unlink;
1532 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
1533 GST_DEBUG_FUNCPTR_NAME (unlink));
1537 * gst_pad_set_getcaps_function:
1539 * @getcaps: the #GstPadGetCapsFunction to set.
1541 * Sets the given getcaps function for the pad. @getcaps should return the
1542 * allowable caps for a pad in the context of the element's state, its link to
1543 * other elements, and the devices or files it has opened. These caps must be a
1544 * subset of the pad template caps. In the NULL state with no links, @getcaps
1545 * should ideally return the same caps as the pad template. In rare
1546 * circumstances, an object property can affect the caps returned by @getcaps,
1547 * but this is discouraged.
1549 * You do not need to call this function if @pad's allowed caps are always the
1550 * same as the pad template caps. This can only be true if the padtemplate
1551 * has fixed simple caps.
1553 * For most filters, the caps returned by @getcaps is directly affected by the
1554 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1555 * the srcpad's getcaps function is directly related to the stream data. Again,
1556 * @getcaps should return the most specific caps it reasonably can, since this
1557 * helps with autoplugging.
1559 * Note that the return value from @getcaps is owned by the caller, so the
1560 * caller should unref the caps after usage.
1563 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1565 g_return_if_fail (GST_IS_PAD (pad));
1567 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1568 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
1569 GST_DEBUG_FUNCPTR_NAME (getcaps));
1573 * gst_pad_set_acceptcaps_function:
1575 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1577 * Sets the given acceptcaps function for the pad. The acceptcaps function
1578 * will be called to check if the pad can accept the given caps. Setting the
1579 * acceptcaps function to NULL restores the default behaviour of allowing
1580 * any caps that matches the caps from gst_pad_get_caps().
1583 gst_pad_set_acceptcaps_function (GstPad * pad,
1584 GstPadAcceptCapsFunction acceptcaps)
1586 g_return_if_fail (GST_IS_PAD (pad));
1588 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1589 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
1590 GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1594 * gst_pad_set_fixatecaps_function:
1596 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1598 * Sets the given fixatecaps function for the pad. The fixatecaps function
1599 * will be called whenever the default values for a GstCaps needs to be
1603 gst_pad_set_fixatecaps_function (GstPad * pad,
1604 GstPadFixateCapsFunction fixatecaps)
1606 g_return_if_fail (GST_IS_PAD (pad));
1608 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1609 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
1610 GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1614 * gst_pad_set_setcaps_function:
1616 * @setcaps: the #GstPadSetCapsFunction to set.
1618 * Sets the given setcaps function for the pad. The setcaps function
1619 * will be called whenever a buffer with a new media type is pushed or
1620 * pulled from the pad. The pad/element needs to update its internal
1621 * structures to process the new media type. If this new type is not
1622 * acceptable, the setcaps function should return FALSE.
1625 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1627 g_return_if_fail (GST_IS_PAD (pad));
1629 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1630 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
1631 GST_DEBUG_FUNCPTR_NAME (setcaps));
1635 * gst_pad_set_bufferalloc_function:
1636 * @pad: a sink #GstPad.
1637 * @bufalloc: the #GstPadBufferAllocFunction to set.
1639 * Sets the given bufferalloc function for the pad. Note that the
1640 * bufferalloc function can only be set on sinkpads.
1643 gst_pad_set_bufferalloc_function (GstPad * pad,
1644 GstPadBufferAllocFunction bufalloc)
1646 g_return_if_fail (GST_IS_PAD (pad));
1647 g_return_if_fail (GST_PAD_IS_SINK (pad));
1649 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1650 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
1651 GST_DEBUG_FUNCPTR_NAME (bufalloc));
1656 * @srcpad: the source #GstPad to unlink.
1657 * @sinkpad: the sink #GstPad to unlink.
1659 * Unlinks the source pad from the sink pad. Will emit the #GstPad::unlinked
1660 * signal on both pads.
1662 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1663 * the pads were not linked together.
1668 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1670 gboolean result = FALSE;
1671 GstElement *parent = NULL;
1673 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1674 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), FALSE);
1675 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1676 g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad), FALSE);
1678 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1679 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1680 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1682 /* We need to notify the parent before taking any pad locks as the bin in
1683 * question might be waiting for a lock on the pad while holding its lock
1684 * that our message will try to take. */
1685 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
1686 if (GST_IS_ELEMENT (parent)) {
1687 gst_element_post_message (parent,
1688 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
1689 GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, TRUE));
1691 gst_object_unref (parent);
1696 GST_OBJECT_LOCK (srcpad);
1698 GST_OBJECT_LOCK (sinkpad);
1700 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1701 goto not_linked_together;
1703 if (GST_PAD_UNLINKFUNC (srcpad)) {
1704 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1706 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1707 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1710 /* first clear peers */
1711 GST_PAD_PEER (srcpad) = NULL;
1712 GST_PAD_PEER (sinkpad) = NULL;
1714 GST_OBJECT_UNLOCK (sinkpad);
1715 GST_OBJECT_UNLOCK (srcpad);
1717 /* fire off a signal to each of the pads telling them
1718 * that they've been unlinked */
1719 g_signal_emit (srcpad, gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1720 g_signal_emit (sinkpad, gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1722 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1723 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1728 if (parent != NULL) {
1729 gst_element_post_message (parent,
1730 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
1731 GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, FALSE));
1732 gst_object_unref (parent);
1737 not_linked_together:
1739 /* we do not emit a warning in this case because unlinking cannot
1740 * be made MT safe.*/
1741 GST_OBJECT_UNLOCK (sinkpad);
1742 GST_OBJECT_UNLOCK (srcpad);
1748 * gst_pad_is_linked:
1749 * @pad: pad to check
1751 * Checks if a @pad is linked to another pad or not.
1753 * Returns: TRUE if the pad is linked, FALSE otherwise.
1758 gst_pad_is_linked (GstPad * pad)
1762 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1764 GST_OBJECT_LOCK (pad);
1765 result = (GST_PAD_PEER (pad) != NULL);
1766 GST_OBJECT_UNLOCK (pad);
1771 /* get the caps from both pads and see if the intersection
1774 * This function should be called with the pad LOCK on both
1778 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1782 gboolean compatible = FALSE;
1784 srccaps = gst_pad_get_caps_unlocked (src);
1785 sinkcaps = gst_pad_get_caps_unlocked (sink);
1787 GST_CAT_DEBUG (GST_CAT_CAPS, "src caps %" GST_PTR_FORMAT, srccaps);
1788 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1790 /* if we have caps on both pads we can check the intersection. If one
1791 * of the caps is NULL, we return TRUE. */
1792 if (G_UNLIKELY (srccaps == NULL || sinkcaps == NULL)) {
1794 gst_caps_unref (srccaps);
1796 gst_caps_unref (sinkcaps);
1800 compatible = gst_caps_can_intersect (srccaps, sinkcaps);
1801 gst_caps_unref (srccaps);
1802 gst_caps_unref (sinkcaps);
1805 GST_CAT_DEBUG (GST_CAT_CAPS, "caps are %scompatible",
1806 (compatible ? "" : "not"));
1811 /* check if the grandparents of both pads are the same.
1812 * This check is required so that we don't try to link
1813 * pads from elements in different bins without ghostpads.
1815 * The LOCK should be held on both pads
1818 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1820 GstObject *psrc, *psink;
1822 psrc = GST_OBJECT_PARENT (src);
1823 psink = GST_OBJECT_PARENT (sink);
1825 /* if one of the pads has no parent, we allow the link */
1826 if (G_UNLIKELY (psrc == NULL || psink == NULL))
1829 /* only care about parents that are elements */
1830 if (G_UNLIKELY (!GST_IS_ELEMENT (psrc) || !GST_IS_ELEMENT (psink)))
1831 goto no_element_parent;
1833 /* if the parents are the same, we have a loop */
1834 if (G_UNLIKELY (psrc == psink))
1837 /* if they both have a parent, we check the grandparents. We can not lock
1838 * the parent because we hold on the child (pad) and the locking order is
1839 * parent >> child. */
1840 psrc = GST_OBJECT_PARENT (psrc);
1841 psink = GST_OBJECT_PARENT (psink);
1843 /* if they have grandparents but they are not the same */
1844 if (G_UNLIKELY (psrc != psink))
1845 goto wrong_grandparents;
1852 GST_CAT_DEBUG (GST_CAT_CAPS,
1853 "one of the pads has no parent %" GST_PTR_FORMAT " and %"
1854 GST_PTR_FORMAT, psrc, psink);
1859 GST_CAT_DEBUG (GST_CAT_CAPS,
1860 "one of the pads has no element parent %" GST_PTR_FORMAT " and %"
1861 GST_PTR_FORMAT, psrc, psink);
1866 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1872 GST_CAT_DEBUG (GST_CAT_CAPS,
1873 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1874 GST_PTR_FORMAT, psrc, psink);
1879 /* FIXME leftover from an attempt at refactoring... */
1880 /* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
1881 * the two pads will be locked in the srcpad, sinkpad order. */
1882 static GstPadLinkReturn
1883 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1885 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1886 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1888 GST_OBJECT_LOCK (srcpad);
1890 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1891 goto src_was_linked;
1893 GST_OBJECT_LOCK (sinkpad);
1895 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1896 goto sink_was_linked;
1898 /* check hierarchy, pads can only be linked if the grandparents
1900 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1901 goto wrong_hierarchy;
1903 /* check pad caps for non-empty intersection */
1904 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1907 /* FIXME check pad scheduling for non-empty intersection */
1909 return GST_PAD_LINK_OK;
1913 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
1914 GST_DEBUG_PAD_NAME (srcpad),
1915 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1916 /* we do not emit a warning in this case because unlinking cannot
1917 * be made MT safe.*/
1918 GST_OBJECT_UNLOCK (srcpad);
1919 return GST_PAD_LINK_WAS_LINKED;
1923 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
1924 GST_DEBUG_PAD_NAME (sinkpad),
1925 GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
1926 /* we do not emit a warning in this case because unlinking cannot
1927 * be made MT safe.*/
1928 GST_OBJECT_UNLOCK (sinkpad);
1929 GST_OBJECT_UNLOCK (srcpad);
1930 return GST_PAD_LINK_WAS_LINKED;
1934 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1935 GST_OBJECT_UNLOCK (sinkpad);
1936 GST_OBJECT_UNLOCK (srcpad);
1937 return GST_PAD_LINK_WRONG_HIERARCHY;
1941 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1942 GST_OBJECT_UNLOCK (sinkpad);
1943 GST_OBJECT_UNLOCK (srcpad);
1944 return GST_PAD_LINK_NOFORMAT;
1950 * @srcpad: the source #GstPad.
1951 * @sinkpad: the sink #GstPad.
1953 * Checks if the source pad and the sink pad are compatible so they can be
1956 * Returns: TRUE if the pads can be linked.
1959 gst_pad_can_link (GstPad * srcpad, GstPad * sinkpad)
1961 GstPadLinkReturn result;
1963 /* generic checks */
1964 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1965 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1967 GST_CAT_INFO (GST_CAT_PADS, "check if %s:%s can link with %s:%s",
1968 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1970 /* gst_pad_link_prepare does everything for us, we only release the locks
1971 * on the pads that it gets us. If this function returns !OK the locks are not
1973 result = gst_pad_link_prepare (srcpad, sinkpad);
1974 if (result != GST_PAD_LINK_OK)
1977 GST_OBJECT_UNLOCK (srcpad);
1978 GST_OBJECT_UNLOCK (sinkpad);
1981 return result == GST_PAD_LINK_OK;
1986 * @srcpad: the source #GstPad to link.
1987 * @sinkpad: the sink #GstPad to link.
1989 * Links the source pad and the sink pad.
1991 * Returns: A result code indicating if the connection worked or
1997 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1999 GstPadLinkReturn result;
2002 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
2003 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), GST_PAD_LINK_WRONG_DIRECTION);
2004 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
2005 g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad),
2006 GST_PAD_LINK_WRONG_DIRECTION);
2008 /* Notify the parent early. See gst_pad_unlink for details. */
2009 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
2010 if (GST_IS_ELEMENT (parent)) {
2011 gst_element_post_message (parent,
2012 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
2013 GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, TRUE));
2015 gst_object_unref (parent);
2020 /* prepare will also lock the two pads */
2021 result = gst_pad_link_prepare (srcpad, sinkpad);
2023 if (result != GST_PAD_LINK_OK)
2026 /* must set peers before calling the link function */
2027 GST_PAD_PEER (srcpad) = sinkpad;
2028 GST_PAD_PEER (sinkpad) = srcpad;
2030 GST_OBJECT_UNLOCK (sinkpad);
2031 GST_OBJECT_UNLOCK (srcpad);
2033 /* FIXME released the locks here, concurrent thread might link
2034 * something else. */
2035 if (GST_PAD_LINKFUNC (srcpad)) {
2036 /* this one will call the peer link function */
2037 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
2038 } else if (GST_PAD_LINKFUNC (sinkpad)) {
2039 /* if no source link function, we need to call the sink link
2040 * function ourselves. */
2041 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
2043 result = GST_PAD_LINK_OK;
2046 GST_OBJECT_LOCK (srcpad);
2047 GST_OBJECT_LOCK (sinkpad);
2049 if (result == GST_PAD_LINK_OK) {
2050 GST_OBJECT_UNLOCK (sinkpad);
2051 GST_OBJECT_UNLOCK (srcpad);
2053 /* fire off a signal to each of the pads telling them
2054 * that they've been linked */
2055 g_signal_emit (srcpad, gst_pad_signals[PAD_LINKED], 0, sinkpad);
2056 g_signal_emit (sinkpad, gst_pad_signals[PAD_LINKED], 0, srcpad);
2058 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
2059 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2061 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
2062 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2064 GST_PAD_PEER (srcpad) = NULL;
2065 GST_PAD_PEER (sinkpad) = NULL;
2067 GST_OBJECT_UNLOCK (sinkpad);
2068 GST_OBJECT_UNLOCK (srcpad);
2073 gst_element_post_message (parent,
2074 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
2075 GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, FALSE));
2076 gst_object_unref (parent);
2083 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
2085 GstPadTemplate **template_p;
2087 /* this function would need checks if it weren't static */
2089 GST_OBJECT_LOCK (pad);
2090 template_p = &pad->padtemplate;
2091 gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
2092 GST_OBJECT_UNLOCK (pad);
2095 gst_pad_template_pad_created (templ, pad);
2099 * gst_pad_get_pad_template:
2102 * Gets the template for @pad.
2104 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
2105 * if this pad has no template.
2107 * FIXME: currently returns an unrefcounted padtemplate.
2110 gst_pad_get_pad_template (GstPad * pad)
2112 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2114 return GST_PAD_PAD_TEMPLATE (pad);
2118 /* should be called with the pad LOCK held */
2119 /* refs the caps, so caller is responsible for getting it unreffed */
2121 gst_pad_get_caps_unlocked (GstPad * pad)
2123 GstCaps *result = NULL;
2124 GstPadTemplate *templ;
2126 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
2128 if (GST_PAD_GETCAPSFUNC (pad)) {
2129 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2130 "dispatching to pad getcaps function");
2132 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
2133 GST_OBJECT_UNLOCK (pad);
2134 result = GST_PAD_GETCAPSFUNC (pad) (pad);
2135 GST_OBJECT_LOCK (pad);
2136 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
2138 if (result == NULL) {
2139 g_critical ("pad %s:%s returned NULL caps from getcaps function",
2140 GST_DEBUG_PAD_NAME (pad));
2142 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2143 "pad getcaps returned %" GST_PTR_FORMAT, result);
2144 #ifndef G_DISABLE_ASSERT
2145 /* check that the returned caps are a real subset of the template caps */
2146 if (GST_PAD_PAD_TEMPLATE (pad)) {
2147 const GstCaps *templ_caps =
2148 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2149 if (!gst_caps_is_subset (result, templ_caps)) {
2152 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
2153 "pad returned caps %" GST_PTR_FORMAT
2154 " which are not a real subset of its template caps %"
2155 GST_PTR_FORMAT, result, templ_caps);
2157 ("pad %s:%s returned caps which are not a real "
2158 "subset of its template caps", GST_DEBUG_PAD_NAME (pad));
2159 temp = gst_caps_intersect (templ_caps, result);
2160 gst_caps_unref (result);
2168 if ((templ = GST_PAD_PAD_TEMPLATE (pad))) {
2169 result = GST_PAD_TEMPLATE_CAPS (templ);
2170 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2171 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
2174 result = gst_caps_ref (result);
2177 if ((result = GST_PAD_CAPS (pad))) {
2178 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2179 "using pad caps %p %" GST_PTR_FORMAT, result, result);
2181 result = gst_caps_ref (result);
2185 /* this almost never happens */
2186 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
2187 result = gst_caps_new_empty ();
2193 /* FIXME-0.11: what about making this the default and using
2194 * gst_caps_make_writable() explicitely where needed
2197 * gst_pad_get_caps_reffed:
2198 * @pad: a #GstPad to get the capabilities of.
2200 * Gets the capabilities this pad can produce or consume. Preferred function if
2201 * one only wants to read or intersect the caps.
2203 * Returns: the caps of the pad with incremented ref-count.
2208 gst_pad_get_caps_reffed (GstPad * pad)
2210 GstCaps *result = NULL;
2212 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2214 GST_OBJECT_LOCK (pad);
2216 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
2218 result = gst_pad_get_caps_unlocked (pad);
2220 GST_OBJECT_UNLOCK (pad);
2227 * @pad: a #GstPad to get the capabilities of.
2229 * Gets the capabilities this pad can produce or consume.
2230 * Note that this method doesn't necessarily return the caps set by
2231 * gst_pad_set_caps() - use GST_PAD_CAPS() for that instead.
2232 * gst_pad_get_caps returns all possible caps a pad can operate with, using
2233 * the pad's get_caps function;
2234 * this returns the pad template caps if not explicitly set.
2236 * Returns: a newly allocated copy of the #GstCaps of this pad.
2241 gst_pad_get_caps (GstPad * pad)
2243 GstCaps *result = gst_pad_get_caps_reffed (pad);
2245 /* be sure that we have a copy */
2246 if (G_LIKELY (result))
2247 result = gst_caps_make_writable (result);
2252 /* FIXME-0.11: what about making this the default and using
2253 * gst_caps_make_writable() explicitely where needed
2256 * gst_pad_peer_get_caps_reffed:
2257 * @pad: a #GstPad to get the capabilities of.
2259 * Gets the capabilities of the peer connected to this pad. Preferred function
2260 * if one only wants to read or intersect the caps.
2262 * Returns: the caps of the pad with incremented ref-count.
2267 gst_pad_peer_get_caps_reffed (GstPad * pad)
2270 GstCaps *result = NULL;
2272 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2274 GST_OBJECT_LOCK (pad);
2276 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2278 peerpad = GST_PAD_PEER (pad);
2279 if (G_UNLIKELY (peerpad == NULL))
2282 gst_object_ref (peerpad);
2283 GST_OBJECT_UNLOCK (pad);
2285 result = gst_pad_get_caps_reffed (peerpad);
2287 gst_object_unref (peerpad);
2293 GST_OBJECT_UNLOCK (pad);
2299 * gst_pad_peer_get_caps:
2300 * @pad: a #GstPad to get the peer capabilities of.
2302 * Gets the capabilities of the peer connected to this pad. Similar to
2303 * gst_pad_get_caps().
2305 * Returns: a newly allocated copy of the #GstCaps of the peer pad. Use
2306 * gst_caps_unref() to get rid of it. This function returns %NULL if there is
2310 gst_pad_peer_get_caps (GstPad * pad)
2313 GstCaps *result = NULL;
2315 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2317 GST_OBJECT_LOCK (pad);
2319 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2321 peerpad = GST_PAD_PEER (pad);
2322 if (G_UNLIKELY (peerpad == NULL))
2325 gst_object_ref (peerpad);
2326 GST_OBJECT_UNLOCK (pad);
2328 result = gst_pad_get_caps (peerpad);
2330 gst_object_unref (peerpad);
2336 GST_OBJECT_UNLOCK (pad);
2342 fixate_value (GValue * dest, const GValue * src)
2344 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
2345 g_value_init (dest, G_TYPE_INT);
2346 g_value_set_int (dest, gst_value_get_int_range_min (src));
2347 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
2348 g_value_init (dest, G_TYPE_DOUBLE);
2349 g_value_set_double (dest, gst_value_get_double_range_min (src));
2350 } else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
2351 gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
2352 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
2353 GValue temp = { 0 };
2355 /* list could be empty */
2356 if (gst_value_list_get_size (src) <= 0)
2359 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
2361 if (!fixate_value (dest, &temp))
2362 gst_value_init_and_copy (dest, &temp);
2363 g_value_unset (&temp);
2364 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
2365 gboolean res = FALSE;
2368 len = gst_value_array_get_size (src);
2369 g_value_init (dest, GST_TYPE_ARRAY);
2370 for (n = 0; n < len; n++) {
2372 const GValue *orig_kid = gst_value_array_get_value (src, n);
2374 if (!fixate_value (&kid, orig_kid))
2375 gst_value_init_and_copy (&kid, orig_kid);
2378 gst_value_array_append_value (dest, &kid);
2379 g_value_unset (&kid);
2383 g_value_unset (dest);
2394 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
2396 GstStructure *s = data;
2399 if (fixate_value (&v, value)) {
2400 gst_structure_id_set_value (s, field_id, &v);
2408 * gst_pad_fixate_caps:
2409 * @pad: a #GstPad to fixate
2410 * @caps: the #GstCaps to fixate
2412 * Fixate a caps on the given pad. Modifies the caps in place, so you should
2413 * make sure that the caps are actually writable (see gst_caps_make_writable()).
2416 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
2418 GstPadFixateCapsFunction fixatefunc;
2421 g_return_if_fail (GST_IS_PAD (pad));
2422 g_return_if_fail (caps != NULL);
2423 g_return_if_fail (!gst_caps_is_empty (caps));
2424 /* FIXME-0.11: do not allow fixating any-caps
2425 * g_return_if_fail (!gst_caps_is_any (caps));
2428 if (gst_caps_is_fixed (caps) || gst_caps_is_any (caps))
2431 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
2433 fixatefunc (pad, caps);
2436 /* default fixation */
2437 gst_caps_truncate (caps);
2438 s = gst_caps_get_structure (caps, 0);
2439 gst_structure_foreach (s, gst_pad_default_fixate, s);
2442 /* Default accept caps implementation just checks against
2443 * against the allowed caps for the pad */
2445 gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
2447 /* get the caps and see if it intersects to something not empty */
2449 gboolean result = FALSE;
2451 GST_DEBUG_OBJECT (pad, "caps %" GST_PTR_FORMAT, caps);
2453 allowed = gst_pad_get_caps_reffed (pad);
2455 goto nothing_allowed;
2457 GST_DEBUG_OBJECT (pad, "allowed caps %" GST_PTR_FORMAT, allowed);
2459 result = gst_caps_can_intersect (allowed, caps);
2461 gst_caps_unref (allowed);
2468 GST_DEBUG_OBJECT (pad, "no caps allowed on the pad");
2474 * gst_pad_accept_caps:
2475 * @pad: a #GstPad to check
2476 * @caps: a #GstCaps to check on the pad
2478 * Check if the given pad accepts the caps.
2480 * Returns: TRUE if the pad can accept the caps.
2483 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2486 GstPadAcceptCapsFunction acceptfunc;
2487 GstCaps *existing = NULL;
2489 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2491 /* any pad can be unnegotiated */
2495 /* lock for checking the existing caps */
2496 GST_OBJECT_LOCK (pad);
2497 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
2498 /* The current caps on a pad are trivially acceptable */
2499 if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
2500 if (caps == existing || gst_caps_is_equal (caps, existing))
2503 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2504 GST_OBJECT_UNLOCK (pad);
2506 if (G_LIKELY (acceptfunc)) {
2507 /* we can call the function */
2508 result = acceptfunc (pad, caps);
2509 GST_DEBUG_OBJECT (pad, "acceptfunc returned %d", result);
2511 /* Only null if the element explicitly unset it */
2512 result = gst_pad_acceptcaps_default (pad, caps);
2513 GST_DEBUG_OBJECT (pad, "default acceptcaps returned %d", result);
2519 GST_DEBUG_OBJECT (pad, "pad had same caps");
2520 GST_OBJECT_UNLOCK (pad);
2526 * gst_pad_peer_accept_caps:
2527 * @pad: a #GstPad to check the peer of
2528 * @caps: a #GstCaps to check on the pad
2530 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2533 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2536 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2541 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2543 GST_OBJECT_LOCK (pad);
2545 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
2547 peerpad = GST_PAD_PEER (pad);
2548 if (G_UNLIKELY (peerpad == NULL))
2551 gst_object_ref (peerpad);
2552 /* release lock before calling external methods but keep ref to pad */
2553 GST_OBJECT_UNLOCK (pad);
2555 result = gst_pad_accept_caps (peerpad, caps);
2557 gst_object_unref (peerpad);
2563 GST_OBJECT_UNLOCK (pad);
2570 * @pad: a #GstPad to set the capabilities of.
2571 * @caps: a #GstCaps to set.
2573 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2574 * caps on the pad will be unreffed. This function refs the caps so you should
2575 * unref if as soon as you don't need it anymore.
2576 * It is possible to set NULL caps, which will make the pad unnegotiated
2579 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2580 * or bad parameters were provided to this function.
2585 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2587 GstPadSetCapsFunction setcaps;
2590 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2591 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2593 GST_OBJECT_LOCK (pad);
2594 existing = GST_PAD_CAPS (pad);
2595 if (existing == caps)
2598 if (gst_caps_is_equal (caps, existing))
2599 goto setting_same_caps;
2601 setcaps = GST_PAD_SETCAPSFUNC (pad);
2603 /* call setcaps function to configure the pad only if the
2604 * caps is not NULL */
2605 if (setcaps != NULL && caps) {
2606 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2607 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2608 GST_OBJECT_UNLOCK (pad);
2609 if (!setcaps (pad, caps))
2611 GST_OBJECT_LOCK (pad);
2612 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2614 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
2618 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2619 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %p %" GST_PTR_FORMAT, caps,
2621 GST_OBJECT_UNLOCK (pad);
2623 g_object_notify (G_OBJECT (pad), "caps");
2629 GST_OBJECT_UNLOCK (pad);
2634 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2635 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2636 "caps %p %" GST_PTR_FORMAT " same as existing, updating ptr only", caps,
2638 GST_OBJECT_UNLOCK (pad);
2645 GST_OBJECT_LOCK (pad);
2646 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2647 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2648 "caps %" GST_PTR_FORMAT " could not be set", caps);
2649 GST_OBJECT_UNLOCK (pad);
2656 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2660 /* See if pad accepts the caps */
2661 if (!gst_pad_accept_caps (pad, caps))
2664 /* set caps on pad if call succeeds */
2665 res = gst_pad_set_caps (pad, caps);
2666 /* no need to unref the caps here, set_caps takes a ref and
2667 * our ref goes away when we leave this function. */
2673 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2674 "caps %" GST_PTR_FORMAT " not accepted", caps);
2679 /* returns TRUE if the src pad could be configured to accept the given caps */
2681 gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
2686 /* See if pad accepts the caps */
2687 if (!gst_pad_accept_caps (pad, caps))
2690 res = gst_pad_set_caps (pad, caps);
2698 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2699 "caps %" GST_PTR_FORMAT " not accepted", caps);
2705 * gst_pad_get_pad_template_caps:
2706 * @pad: a #GstPad to get the template capabilities from.
2708 * Gets the capabilities for @pad's template.
2710 * Returns: the #GstCaps of this pad template. If you intend to keep a
2711 * reference on the caps, make a copy (see gst_caps_copy ()).
2714 gst_pad_get_pad_template_caps (GstPad * pad)
2716 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2718 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2720 if (GST_PAD_PAD_TEMPLATE (pad))
2721 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2723 return gst_static_caps_get (&anycaps);
2728 * @pad: a #GstPad to get the peer of.
2730 * Gets the peer of @pad. This function refs the peer pad so
2731 * you need to unref it after use.
2733 * Returns: the peer #GstPad. Unref after usage.
2738 gst_pad_get_peer (GstPad * pad)
2742 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2744 GST_OBJECT_LOCK (pad);
2745 result = GST_PAD_PEER (pad);
2747 gst_object_ref (result);
2748 GST_OBJECT_UNLOCK (pad);
2754 * gst_pad_get_allowed_caps:
2757 * Gets the capabilities of the allowed media types that can flow through
2758 * @pad and its peer.
2760 * The allowed capabilities is calculated as the intersection of the results of
2761 * calling gst_pad_get_caps() on @pad and its peer. The caller owns a reference
2762 * on the resulting caps.
2764 * Returns: the allowed #GstCaps of the pad link. Unref the caps when you no
2765 * longer need it. This function returns NULL when @pad has no peer.
2770 gst_pad_get_allowed_caps (GstPad * pad)
2777 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2779 GST_OBJECT_LOCK (pad);
2781 peer = GST_PAD_PEER (pad);
2782 if (G_UNLIKELY (peer == NULL))
2785 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting allowed caps");
2787 gst_object_ref (peer);
2788 GST_OBJECT_UNLOCK (pad);
2789 mycaps = gst_pad_get_caps_reffed (pad);
2791 peercaps = gst_pad_get_caps_reffed (peer);
2792 gst_object_unref (peer);
2794 caps = gst_caps_intersect (mycaps, peercaps);
2795 gst_caps_unref (peercaps);
2796 gst_caps_unref (mycaps);
2798 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "allowed caps %" GST_PTR_FORMAT,
2805 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2806 GST_OBJECT_UNLOCK (pad);
2813 * gst_pad_get_negotiated_caps:
2816 * Gets the capabilities of the media type that currently flows through @pad
2819 * This function can be used on both src and sinkpads. Note that srcpads are
2820 * always negotiated before sinkpads so it is possible that the negotiated caps
2821 * on the srcpad do not match the negotiated caps of the peer.
2823 * Returns: the negotiated #GstCaps of the pad link. Unref the caps when
2824 * you no longer need it. This function returns NULL when the @pad has no
2825 * peer or is not negotiated yet.
2830 gst_pad_get_negotiated_caps (GstPad * pad)
2835 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2837 GST_OBJECT_LOCK (pad);
2839 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2842 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
2844 caps = GST_PAD_CAPS (pad);
2846 gst_caps_ref (caps);
2847 GST_OBJECT_UNLOCK (pad);
2849 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
2856 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2857 GST_OBJECT_UNLOCK (pad);
2863 /* calls the buffer_alloc function on the given pad */
2864 static GstFlowReturn
2865 gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
2866 GstCaps * caps, GstBuffer ** buf)
2869 GstPadBufferAllocFunction bufferallocfunc;
2871 GST_OBJECT_LOCK (pad);
2872 /* when the pad is flushing we cannot give a buffer */
2873 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2876 bufferallocfunc = pad->bufferallocfunc;
2878 if (offset == GST_BUFFER_OFFSET_NONE) {
2879 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2880 "calling bufferallocfunc &%s (@%p) for size %d offset NONE",
2881 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), bufferallocfunc, size);
2883 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2884 "calling bufferallocfunc &%s (@%p) of for size %d offset %"
2885 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2886 bufferallocfunc, size, offset);
2888 GST_OBJECT_UNLOCK (pad);
2890 /* G_LIKELY for now since most elements don't implement a buffer alloc
2891 * function and there is no default alloc proxy function as this is usually
2893 if (G_LIKELY (bufferallocfunc == NULL))
2896 ret = bufferallocfunc (pad, offset, size, caps, buf);
2898 if (G_UNLIKELY (ret != GST_FLOW_OK))
2901 /* no error, but NULL buffer means fallback to the default */
2902 if (G_UNLIKELY (*buf == NULL))
2905 /* If the buffer alloc function didn't set up the caps like it should,
2907 if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
2908 GST_WARNING_OBJECT (pad,
2909 "Buffer allocation function did not set caps. Setting");
2910 gst_buffer_set_caps (*buf, caps);
2916 /* pad was flushing */
2917 GST_OBJECT_UNLOCK (pad);
2918 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
2919 return GST_FLOW_WRONG_STATE;
2923 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2924 "alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
2929 /* fallback case, allocate a buffer of our own, add pad caps. */
2930 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
2932 if ((*buf = gst_buffer_try_new_and_alloc (size))) {
2933 GST_BUFFER_OFFSET (*buf) = offset;
2934 gst_buffer_set_caps (*buf, caps);
2937 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2938 "out of memory allocating %d bytes", size);
2939 return GST_FLOW_ERROR;
2944 /* FIXME 0.11: size should be unsigned */
2945 static GstFlowReturn
2946 gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
2947 GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
2952 gboolean caps_changed;
2954 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2955 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2956 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2957 g_return_val_if_fail (size >= 0, GST_FLOW_ERROR);
2959 GST_DEBUG_OBJECT (pad, "offset %" G_GUINT64_FORMAT ", size %d, caps %"
2960 GST_PTR_FORMAT, offset, size, caps);
2962 GST_OBJECT_LOCK (pad);
2963 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2964 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
2967 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2970 gst_object_ref (peer);
2971 GST_OBJECT_UNLOCK (pad);
2973 ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
2974 gst_object_unref (peer);
2976 if (G_UNLIKELY (ret != GST_FLOW_OK))
2979 /* FIXME, move capnego this into a base class? */
2980 newcaps = GST_BUFFER_CAPS (*buf);
2982 /* Lock for checking caps, pretty pointless as the _pad_push() function might
2983 * change it concurrently, one of the problems with automatic caps setting in
2984 * pad_alloc_and_set_caps. Worst case, if does a check too much, but only
2985 * when there is heavy renegotiation going on in both directions. */
2986 GST_OBJECT_LOCK (pad);
2987 caps_changed = newcaps && newcaps != GST_PAD_CAPS (pad);
2988 GST_OBJECT_UNLOCK (pad);
2990 /* we got a new datatype on the pad, see if it can handle it */
2991 if (G_UNLIKELY (caps_changed)) {
2992 GST_DEBUG_OBJECT (pad,
2993 "caps changed from %" GST_PTR_FORMAT " to %p %" GST_PTR_FORMAT,
2994 GST_PAD_CAPS (pad), newcaps, newcaps);
2995 if (G_UNLIKELY (!gst_pad_configure_src (pad, newcaps, setcaps)))
2996 goto not_negotiated;
2999 /* sanity check (only if caps are the same) */
3000 if (G_LIKELY (newcaps == caps) && G_UNLIKELY (GST_BUFFER_SIZE (*buf) < size))
3001 goto wrong_size_fallback;
3007 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
3008 GST_OBJECT_UNLOCK (pad);
3013 /* pad has no peer */
3014 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3015 "called bufferallocfunc but had no peer");
3016 GST_OBJECT_UNLOCK (pad);
3017 return GST_FLOW_NOT_LINKED;
3021 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3022 "alloc function returned error %s", gst_flow_get_name (ret));
3027 gst_buffer_unref (*buf);
3029 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3030 "alloc function returned unacceptable buffer");
3031 return GST_FLOW_NOT_NEGOTIATED;
3033 wrong_size_fallback:
3035 GST_CAT_ERROR_OBJECT (GST_CAT_PADS, pad, "buffer returned by alloc "
3036 "function is too small (%u < %d), doing fallback buffer alloc",
3037 GST_BUFFER_SIZE (*buf), size);
3039 gst_buffer_unref (*buf);
3041 if ((*buf = gst_buffer_try_new_and_alloc (size))) {
3042 GST_BUFFER_OFFSET (*buf) = offset;
3043 gst_buffer_set_caps (*buf, caps);
3046 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3047 "out of memory allocating %d bytes", size);
3048 return GST_FLOW_ERROR;
3054 * gst_pad_alloc_buffer:
3055 * @pad: a source #GstPad
3056 * @offset: the offset of the new buffer in the stream
3057 * @size: the size of the new buffer
3058 * @caps: the caps of the new buffer
3059 * @buf: a newly allocated buffer
3061 * Allocates a new, empty buffer optimized to push to pad @pad. This
3062 * function only works if @pad is a source pad and has a peer.
3064 * A new, empty #GstBuffer will be put in the @buf argument.
3065 * You need to check the caps of the buffer after performing this
3066 * function and renegotiate to the format if needed. If the caps changed, it is
3067 * possible that the buffer returned in @buf is not of the right size for the
3068 * new format, @buf needs to be unreffed and reallocated if this is the case.
3070 * Returns: a result code indicating success of the operation. Any
3071 * result code other than #GST_FLOW_OK is an error and @buf should
3073 * An error can occur if the pad is not connected or when the downstream
3074 * peer elements cannot provide an acceptable buffer.
3079 /* FIXME 0.11: size should be unsigned */
3081 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
3084 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
3088 * gst_pad_alloc_buffer_and_set_caps:
3089 * @pad: a source #GstPad
3090 * @offset: the offset of the new buffer in the stream
3091 * @size: the size of the new buffer
3092 * @caps: the caps of the new buffer
3093 * @buf: a newly allocated buffer
3095 * In addition to the function gst_pad_alloc_buffer(), this function
3096 * automatically calls gst_pad_set_caps() when the caps of the
3097 * newly allocated buffer are different from the @pad caps.
3099 * After a renegotiation, the size of the new buffer returned in @buf could
3100 * be of the wrong size for the new format and must be unreffed an reallocated
3103 * Returns: a result code indicating success of the operation. Any
3104 * result code other than #GST_FLOW_OK is an error and @buf should
3106 * An error can occur if the pad is not connected or when the downstream
3107 * peer elements cannot provide an acceptable buffer.
3112 /* FIXME 0.11: size should be unsigned */
3114 gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
3115 GstCaps * caps, GstBuffer ** buf)
3117 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
3121 #ifndef GST_REMOVE_DEPRECATED
3129 int_link_iter_data_free (IntLinkIterData * data)
3131 g_list_free (data->list);
3132 g_slice_free (IntLinkIterData, data);
3136 static GstIteratorItem
3137 iterate_pad (GstIterator * it, GstPad * pad)
3139 gst_object_ref (pad);
3140 return GST_ITERATOR_ITEM_PASS;
3144 * gst_pad_iterate_internal_links_default:
3145 * @pad: the #GstPad to get the internal links of.
3147 * Iterate the list of pads to which the given pad is linked to inside of
3148 * the parent element.
3149 * This is the default handler, and thus returns an iterator of all of the
3150 * pads inside the parent element with opposite direction.
3152 * The caller must free this iterator after use with gst_iterator_free().
3154 * Returns: a #GstIterator of #GstPad, or NULL if @pad has no parent. Unref each
3155 * returned pad with gst_object_unref().
3160 gst_pad_iterate_internal_links_default (GstPad * pad)
3167 GstIteratorDisposeFunction dispose;
3169 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3171 #ifndef GST_REMOVE_DEPRECATED
3172 /* when we get here, the default handler for the iterate links is called,
3173 * which means that the user has not installed a custom one. We first check if
3174 * there is maybe a custom legacy function we can call. */
3175 if (GST_PAD_INTLINKFUNC (pad) &&
3176 GST_PAD_INTLINKFUNC (pad) != gst_pad_get_internal_links_default) {
3177 IntLinkIterData *data;
3179 /* make an iterator for the list. We can't protect the list with a
3180 * cookie. If we would take the cookie of the parent element, we need to
3181 * have a parent, which is not required for GST_PAD_INTLINKFUNC(). We could
3182 * cache the per-pad list and invalidate the list when a new call to
3183 * INTLINKFUNC() returned a different list but then this would only work if
3184 * two concurrent iterators were used and the last iterator would still be
3185 * thread-unsafe. Just don't use this method anymore. */
3186 data = g_slice_new (IntLinkIterData);
3187 data->list = GST_PAD_INTLINKFUNC (pad) (pad);
3190 GST_WARNING_OBJECT (pad, "Making unsafe iterator");
3192 cookie = &data->cookie;
3193 padlist = &data->list;
3195 dispose = (GstIteratorDisposeFunction) int_link_iter_data_free;
3196 /* reuse the pad lock, it's all we have here */
3197 lock = GST_OBJECT_GET_LOCK (pad);
3203 GST_OBJECT_LOCK (pad);
3204 parent = GST_PAD_PARENT (pad);
3205 if (!parent || !GST_IS_ELEMENT (parent))
3208 gst_object_ref (parent);
3209 GST_OBJECT_UNLOCK (pad);
3211 if (pad->direction == GST_PAD_SRC)
3212 padlist = &parent->sinkpads;
3214 padlist = &parent->srcpads;
3216 GST_DEBUG_OBJECT (pad, "Making iterator");
3218 cookie = &parent->pads_cookie;
3220 dispose = (GstIteratorDisposeFunction) gst_object_unref;
3221 lock = GST_OBJECT_GET_LOCK (parent);
3224 res = gst_iterator_new_list (GST_TYPE_PAD,
3225 lock, cookie, padlist, owner, (GstIteratorItemFunction) iterate_pad,
3233 GST_OBJECT_UNLOCK (pad);
3234 GST_DEBUG_OBJECT (pad, "no parent element");
3240 * gst_pad_iterate_internal_links:
3241 * @pad: the GstPad to get the internal links of.
3243 * Gets an iterator for the pads to which the given pad is linked to inside
3244 * of the parent element.
3246 * Each #GstPad element yielded by the iterator will have its refcount increased,
3247 * so unref after use.
3249 * Returns: a new #GstIterator of #GstPad or %NULL when the pad does not have an
3250 * iterator function configured. Use gst_iterator_free() after usage.
3255 gst_pad_iterate_internal_links (GstPad * pad)
3257 GstIterator *res = NULL;
3259 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3261 if (GST_PAD_ITERINTLINKFUNC (pad))
3262 res = GST_PAD_ITERINTLINKFUNC (pad) (pad);
3267 #ifndef GST_REMOVE_DEPRECATED
3269 add_unref_pad_to_list (GstPad * pad, GList ** list)
3271 *list = g_list_prepend (*list, pad);
3272 gst_object_unref (pad);
3277 * gst_pad_get_internal_links_default:
3278 * @pad: the #GstPad to get the internal links of.
3280 * Gets a list of pads to which the given pad is linked to
3281 * inside of the parent element.
3282 * This is the default handler, and thus returns a list of all of the
3283 * pads inside the parent element with opposite direction.
3285 * The caller must free this list after use with g_list_free().
3287 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
3291 * Deprecated: This function does not ref the pads in the list so that they
3292 * could become invalid by the time the application accesses them. It's also
3293 * possible that the list changes while handling the pads, which the caller of
3294 * this function is unable to know. Use the thread-safe
3295 * gst_pad_iterate_internal_links_default() instead.
3297 #ifndef GST_REMOVE_DEPRECATED
3299 gst_pad_get_internal_links_default (GstPad * pad)
3304 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3306 GST_WARNING_OBJECT (pad, "Unsafe internal links used");
3308 /* when we get here, the default handler for get_internal_links is called,
3309 * which means that the user has not installed a custom one. We first check if
3310 * there is maybe a custom iterate function we can call. */
3311 if (GST_PAD_ITERINTLINKFUNC (pad) &&
3312 GST_PAD_ITERINTLINKFUNC (pad) != gst_pad_iterate_internal_links_default) {
3314 GstIteratorResult ires;
3315 gboolean done = FALSE;
3317 it = gst_pad_iterate_internal_links (pad);
3318 /* loop over the iterator and put all elements into a list, we also
3319 * immediatly unref them, which is bad. */
3321 ires = gst_iterator_foreach (it, (GFunc) add_unref_pad_to_list, &res);
3323 case GST_ITERATOR_OK:
3324 case GST_ITERATOR_DONE:
3325 case GST_ITERATOR_ERROR:
3328 case GST_ITERATOR_RESYNC:
3329 /* restart, discard previous list */
3330 gst_iterator_resync (it);
3337 gst_iterator_free (it);
3339 /* lock pad, check and ref parent */
3340 GST_OBJECT_LOCK (pad);
3341 parent = GST_PAD_PARENT (pad);
3342 if (!parent || !GST_IS_ELEMENT (parent))
3345 parent = gst_object_ref (parent);
3346 GST_OBJECT_UNLOCK (pad);
3348 /* now lock the parent while we copy the pads */
3349 GST_OBJECT_LOCK (parent);
3350 if (pad->direction == GST_PAD_SRC)
3351 res = g_list_copy (parent->sinkpads);
3353 res = g_list_copy (parent->srcpads);
3354 GST_OBJECT_UNLOCK (parent);
3356 gst_object_unref (parent);
3359 /* At this point pads can be changed and unreffed. Nothing we can do about it
3360 * because for compatibility reasons this function cannot ref the pads or
3361 * notify the app that the list changed. */
3367 GST_DEBUG_OBJECT (pad, "no parent");
3368 GST_OBJECT_UNLOCK (pad);
3372 #endif /* GST_REMOVE_DEPRECATED */
3375 * gst_pad_get_internal_links:
3376 * @pad: the #GstPad to get the internal links of.
3378 * Gets a list of pads to which the given pad is linked to
3379 * inside of the parent element.
3380 * The caller must free this list after use.
3384 * Returns: a newly allocated #GList of pads, free with g_list_free().
3386 * Deprecated: This function does not ref the pads in the list so that they
3387 * could become invalid by the time the application accesses them. It's also
3388 * possible that the list changes while handling the pads, which the caller of
3389 * this function is unable to know. Use the thread-safe
3390 * gst_pad_iterate_internal_links() instead.
3392 #ifndef GST_REMOVE_DEPRECATED
3393 #ifdef GST_DISABLE_DEPRECATED
3394 GList *gst_pad_get_internal_links (GstPad * pad);
3397 gst_pad_get_internal_links (GstPad * pad)
3401 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3403 GST_WARNING_OBJECT (pad, "Calling unsafe internal links");
3405 if (GST_PAD_INTLINKFUNC (pad))
3406 res = GST_PAD_INTLINKFUNC (pad) (pad);
3410 #endif /* GST_REMOVE_DEPRECATED */
3413 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
3415 gboolean result = FALSE;
3417 gboolean done = FALSE;
3420 GList *pushed_pads = NULL;
3422 GST_INFO_OBJECT (pad, "Sending event %p (%s) to all internally linked pads",
3423 event, GST_EVENT_TYPE_NAME (event));
3425 iter = gst_pad_iterate_internal_links (pad);
3431 switch (gst_iterator_next (iter, &item)) {
3432 case GST_ITERATOR_OK:
3433 eventpad = GST_PAD_CAST (item);
3435 /* if already pushed, skip */
3436 if (g_list_find (pushed_pads, eventpad)) {
3437 gst_object_unref (item);
3441 if (GST_PAD_IS_SRC (eventpad)) {
3442 /* for each pad we send to, we should ref the event; it's up
3443 * to downstream to unref again when handled. */
3444 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
3445 event, GST_EVENT_TYPE_NAME (event),
3446 GST_DEBUG_PAD_NAME (eventpad));
3447 gst_event_ref (event);
3448 result |= gst_pad_push_event (eventpad, event);
3450 /* we only send the event on one pad, multi-sinkpad elements
3451 * should implement a handler */
3452 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
3453 event, GST_EVENT_TYPE_NAME (event),
3454 GST_DEBUG_PAD_NAME (eventpad));
3455 result = gst_pad_push_event (eventpad, event);
3460 pushed_pads = g_list_prepend (pushed_pads, eventpad);
3462 gst_object_unref (item);
3464 case GST_ITERATOR_RESYNC:
3465 /* FIXME, if we want to reset the result value we need to remember which
3466 * pads pushed with which result */
3467 gst_iterator_resync (iter);
3469 case GST_ITERATOR_ERROR:
3470 GST_ERROR_OBJECT (pad, "Could not iterate over internally linked pads");
3473 case GST_ITERATOR_DONE:
3478 gst_iterator_free (iter);
3482 /* If this is a sinkpad and we don't have pads to send the event to, we
3483 * return TRUE. This is so that when using the default handler on a sink
3484 * element, we don't fail to push it. */
3486 result = GST_PAD_IS_SINK (pad);
3488 g_list_free (pushed_pads);
3490 /* we handled the incoming event so we unref once */
3492 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
3493 gst_event_unref (event);
3500 * gst_pad_event_default:
3501 * @pad: a #GstPad to call the default event handler on.
3502 * @event: the #GstEvent to handle.
3504 * Invokes the default event handler for the given pad. End-of-stream and
3505 * discontinuity events are handled specially, and then the event is sent to all
3506 * pads internally linked to @pad. Note that if there are many possible sink
3507 * pads that are internally linked to @pad, only one will be sent an event.
3508 * Multi-sinkpad elements should implement custom event handlers.
3510 * Returns: TRUE if the event was sent succesfully.
3513 gst_pad_event_default (GstPad * pad, GstEvent * event)
3515 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3516 g_return_val_if_fail (event != NULL, FALSE);
3518 GST_LOG_OBJECT (pad, "default event handler");
3520 switch (GST_EVENT_TYPE (event)) {
3523 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
3524 gst_pad_pause_task (pad);
3531 return gst_pad_event_default_dispatch (pad, event);
3535 * gst_pad_dispatcher:
3536 * @pad: a #GstPad to dispatch.
3537 * @dispatch: the #GstPadDispatcherFunction to call.
3538 * @data: gpointer user data passed to the dispatcher function.
3540 * Invokes the given dispatcher function on each respective peer of
3541 * all pads that are internally linked to the given pad.
3542 * The GstPadDispatcherFunction should return TRUE when no further pads
3543 * need to be processed.
3545 * Returns: TRUE if one of the dispatcher functions returned TRUE.
3548 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
3551 gboolean res = FALSE;
3552 GstIterator *iter = NULL;
3553 gboolean done = FALSE;
3556 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3557 g_return_val_if_fail (dispatch != NULL, FALSE);
3559 iter = gst_pad_iterate_internal_links (pad);
3565 switch (gst_iterator_next (iter, &item)) {
3566 case GST_ITERATOR_OK:
3568 GstPad *int_pad = GST_PAD_CAST (item);
3569 GstPad *int_peer = gst_pad_get_peer (int_pad);
3572 GST_DEBUG_OBJECT (int_pad, "dispatching to peer %s:%s",
3573 GST_DEBUG_PAD_NAME (int_peer));
3574 done = res = dispatch (int_peer, data);
3575 gst_object_unref (int_peer);
3577 GST_DEBUG_OBJECT (int_pad, "no peer");
3580 gst_object_unref (item);
3582 case GST_ITERATOR_RESYNC:
3583 gst_iterator_resync (iter);
3585 case GST_ITERATOR_ERROR:
3587 GST_ERROR_OBJECT (pad, "Could not iterate internally linked pads");
3589 case GST_ITERATOR_DONE:
3594 gst_iterator_free (iter);
3596 GST_DEBUG_OBJECT (pad, "done, result %d", res);
3605 * @pad: a #GstPad to invoke the default query on.
3606 * @query: the #GstQuery to perform.
3608 * Dispatches a query to a pad. The query should have been allocated by the
3609 * caller via one of the type-specific allocation functions in gstquery.h. The
3610 * element is responsible for filling the query with an appropriate response,
3611 * which should then be parsed with a type-specific query parsing function.
3613 * Again, the caller is responsible for both the allocation and deallocation of
3614 * the query structure.
3616 * Returns: TRUE if the query could be performed.
3619 gst_pad_query (GstPad * pad, GstQuery * query)
3621 GstPadQueryFunction func;
3623 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3624 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
3626 GST_DEBUG_OBJECT (pad, "sending query %p", query);
3628 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
3631 return func (pad, query);
3635 GST_DEBUG_OBJECT (pad, "had no query function");
3641 * gst_pad_peer_query:
3642 * @pad: a #GstPad to invoke the peer query on.
3643 * @query: the #GstQuery to perform.
3645 * Performs gst_pad_query() on the peer of @pad.
3647 * The caller is responsible for both the allocation and deallocation of
3648 * the query structure.
3650 * Returns: TRUE if the query could be performed. This function returns %FALSE
3651 * if @pad has no peer.
3656 gst_pad_peer_query (GstPad * pad, GstQuery * query)
3661 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3662 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
3664 GST_OBJECT_LOCK (pad);
3666 GST_DEBUG_OBJECT (pad, "peer query");
3668 peerpad = GST_PAD_PEER (pad);
3669 if (G_UNLIKELY (peerpad == NULL))
3672 gst_object_ref (peerpad);
3673 GST_OBJECT_UNLOCK (pad);
3675 result = gst_pad_query (peerpad, query);
3677 gst_object_unref (peerpad);
3684 GST_WARNING_OBJECT (pad, "pad has no peer");
3685 GST_OBJECT_UNLOCK (pad);
3691 * gst_pad_query_default:
3692 * @pad: a #GstPad to call the default query handler on.
3693 * @query: the #GstQuery to handle.
3695 * Invokes the default query handler for the given pad.
3696 * The query is sent to all pads internally linked to @pad. Note that
3697 * if there are many possible sink pads that are internally linked to
3698 * @pad, only one will be sent the query.
3699 * Multi-sinkpad elements should implement custom query handlers.
3701 * Returns: TRUE if the query was performed succesfully.
3704 gst_pad_query_default (GstPad * pad, GstQuery * query)
3706 switch (GST_QUERY_TYPE (query)) {
3707 case GST_QUERY_POSITION:
3708 case GST_QUERY_SEEKING:
3709 case GST_QUERY_FORMATS:
3710 case GST_QUERY_LATENCY:
3711 case GST_QUERY_JITTER:
3712 case GST_QUERY_RATE:
3713 case GST_QUERY_CONVERT:
3715 return gst_pad_dispatcher
3716 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
3720 #ifndef GST_DISABLE_LOADSAVE
3721 /* FIXME: why isn't this on a GstElement ? */
3723 * gst_pad_load_and_link:
3724 * @self: an #xmlNodePtr to read the description from.
3725 * @parent: the #GstObject element that owns the pad.
3727 * Reads the pad definition from the XML node and links the given pad
3728 * in the element to a pad of an element up in the hierarchy.
3731 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
3733 xmlNodePtr field = self->xmlChildrenNode;
3734 GstPad *pad = NULL, *targetpad;
3735 GstPadTemplate *tmpl;
3739 GstObject *grandparent;
3743 if (!strcmp ((char *) field->name, "name")) {
3744 name = (gchar *) xmlNodeGetContent (field);
3745 pad = gst_element_get_static_pad (GST_ELEMENT (parent), name);
3746 if ((!pad) || ((tmpl = gst_pad_get_pad_template (pad))
3747 && (GST_PAD_REQUEST == GST_PAD_TEMPLATE_PRESENCE (tmpl))))
3748 pad = gst_element_get_request_pad (GST_ELEMENT (parent), name);
3750 } else if (!strcmp ((char *) field->name, "peer")) {
3751 peer = (gchar *) xmlNodeGetContent (field);
3753 field = field->next;
3755 g_return_if_fail (pad != NULL);
3760 split = g_strsplit (peer, ".", 2);
3762 if (split[0] == NULL || split[1] == NULL) {
3763 GST_CAT_DEBUG_OBJECT (GST_CAT_XML, pad,
3764 "Could not parse peer '%s', leaving unlinked", peer);
3771 g_return_if_fail (split[0] != NULL);
3772 g_return_if_fail (split[1] != NULL);
3774 grandparent = gst_object_get_parent (parent);
3776 if (grandparent && GST_IS_BIN (grandparent)) {
3777 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
3784 targetpad = gst_element_get_static_pad (target, split[1]);
3786 targetpad = gst_element_get_request_pad (target, split[1]);
3788 if (targetpad == NULL)
3791 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
3792 gst_pad_link (pad, targetpad);
3794 gst_pad_link (targetpad, pad);
3801 * gst_pad_save_thyself:
3802 * @pad: a #GstPad to save.
3803 * @parent: the parent #xmlNodePtr to save the description in.
3805 * Saves the pad into an xml representation.
3807 * Returns: the #xmlNodePtr representation of the pad.
3810 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
3815 g_return_val_if_fail (GST_IS_PAD (object), NULL);
3817 pad = GST_PAD_CAST (object);
3819 xmlNewChild (parent, NULL, (xmlChar *) "name",
3820 (xmlChar *) GST_PAD_NAME (pad));
3822 if (GST_PAD_IS_SRC (pad)) {
3823 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "source");
3824 } else if (GST_PAD_IS_SINK (pad)) {
3825 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "sink");
3827 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "unknown");
3830 if (GST_PAD_PEER (pad) != NULL) {
3833 peer = GST_PAD_PEER (pad);
3834 /* first check to see if the peer's parent's parent is the same */
3835 /* we just save it off */
3836 content = g_strdup_printf ("%s.%s",
3837 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
3838 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
3841 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
3848 * gst_ghost_pad_save_thyself:
3849 * @pad: a ghost #GstPad to save.
3850 * @parent: the parent #xmlNodePtr to save the description in.
3852 * Saves the ghost pad into an xml representation.
3854 * Returns: the #xmlNodePtr representation of the pad.
3857 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
3861 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
3863 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
3864 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
3865 xmlNewChild (self, NULL, (xmlChar *) "parent",
3866 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
3868 /* FIXME FIXME FIXME! */
3873 #endif /* GST_DISABLE_LOADSAVE */
3876 * should be called with pad OBJECT_LOCK and STREAM_LOCK held.
3877 * GST_PAD_IS_BLOCKED (pad) == TRUE when this function is
3880 * This function performs the pad blocking when an event, buffer push
3881 * or buffer_alloc is performed on a _SRC_ pad. It blocks the
3882 * streaming thread after informing the pad has been blocked.
3884 * An application can with this method wait and block any streaming
3885 * thread and perform operations such as seeking or linking.
3887 * Two methods are available for notifying the application of the
3889 * - the callback method, which happens in the STREAMING thread with
3890 * the STREAM_LOCK held. With this method, the most useful way of
3891 * dealing with the callback is to post a message to the main thread
3892 * where the pad block can then be handled outside of the streaming
3893 * thread. With the last method one can perform all operations such
3894 * as doing a state change, linking, unblocking, seeking etc on the
3896 * - the GCond signal method, which makes any thread unblock when
3897 * the pad block happens.
3899 * During the actual blocking state, the GST_PAD_BLOCKING flag is set.
3900 * The GST_PAD_BLOCKING flag is unset when the pad was unblocked.
3904 static GstFlowReturn
3905 handle_pad_block (GstPad * pad)
3907 GstPadBlockCallback callback;
3909 GstFlowReturn ret = GST_FLOW_OK;
3911 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
3913 /* flushing, don't bother trying to block and return WRONG_STATE
3915 if (GST_PAD_IS_FLUSHING (pad))
3916 goto flushingnonref;
3918 /* we grab an extra ref for the callbacks, this is probably not
3919 * needed (callback code does not have a ref and cannot unref). I
3920 * think this was done to make it possible to unref the element in
3921 * the callback, which is in the end totally impossible as it
3922 * requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
3923 * all taken when calling this function. */
3924 gst_object_ref (pad);
3926 while (GST_PAD_IS_BLOCKED (pad)) {
3928 /* we either have a callback installed to notify the block or
3929 * some other thread is doing a GCond wait. */
3930 callback = pad->block_callback;
3931 pad->abidata.ABI.block_callback_called = TRUE;
3933 /* there is a callback installed, call it. We release the
3934 * lock so that the callback can do something usefull with the
3936 user_data = pad->block_data;
3937 GST_OBJECT_UNLOCK (pad);
3938 callback (pad, TRUE, user_data);
3939 GST_OBJECT_LOCK (pad);
3941 /* we released the lock, recheck flushing */
3942 if (GST_PAD_IS_FLUSHING (pad))
3945 /* no callback, signal the thread that is doing a GCond wait
3947 GST_PAD_BLOCK_BROADCAST (pad);
3949 } while (pad->abidata.ABI.block_callback_called == FALSE
3950 && GST_PAD_IS_BLOCKED (pad));
3952 /* OBJECT_LOCK could have been released when we did the callback, which
3953 * then could have made the pad unblock so we need to check the blocking
3954 * condition again. */
3955 if (!GST_PAD_IS_BLOCKED (pad))
3958 /* now we block the streaming thread. It can be unlocked when we
3959 * deactivate the pad (which will also set the FLUSHING flag) or
3960 * when the pad is unblocked. A flushing event will also unblock
3961 * the pad after setting the FLUSHING flag. */
3962 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3963 "Waiting to be unblocked or set flushing");
3964 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKING);
3965 GST_PAD_BLOCK_WAIT (pad);
3966 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKING);
3968 /* see if we got unblocked by a flush or not */
3969 if (GST_PAD_IS_FLUSHING (pad))
3973 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
3975 /* when we get here, the pad is unblocked again and we perform
3976 * the needed unblock code. */
3977 callback = pad->block_callback;
3979 /* we need to call the callback */
3980 user_data = pad->block_data;
3981 GST_OBJECT_UNLOCK (pad);
3982 callback (pad, FALSE, user_data);
3983 GST_OBJECT_LOCK (pad);
3985 /* we need to signal the thread waiting on the GCond */
3986 GST_PAD_BLOCK_BROADCAST (pad);
3989 gst_object_unref (pad);
3995 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
3996 return GST_FLOW_WRONG_STATE;
4000 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
4001 gst_object_unref (pad);
4002 return GST_FLOW_WRONG_STATE;
4006 /**********************************************************************
4007 * Data passing functions
4011 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
4014 GValue args[2] = { {0}, {0} };
4019 g_value_init (&ret, G_TYPE_BOOLEAN);
4020 g_value_set_boolean (&ret, TRUE);
4021 g_value_init (&args[0], GST_TYPE_PAD);
4022 g_value_set_object (&args[0], pad);
4023 g_value_init (&args[1], GST_TYPE_MINI_OBJECT);
4024 gst_value_set_mini_object (&args[1], obj);
4026 if (GST_IS_EVENT (obj))
4027 detail = event_quark;
4029 detail = buffer_quark;
4032 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
4033 res = g_value_get_boolean (&ret);
4036 g_value_unset (&ret);
4037 g_value_unset (&args[0]);
4038 g_value_unset (&args[1]);
4044 gst_pad_data_unref (gboolean is_buffer, void *data)
4046 if (G_LIKELY (is_buffer)) {
4047 gst_buffer_unref (data);
4049 gst_buffer_list_unref (data);
4054 gst_pad_data_get_caps (gboolean is_buffer, void *data)
4058 if (G_LIKELY (is_buffer)) {
4059 caps = GST_BUFFER_CAPS (data);
4063 if ((buf = gst_buffer_list_get (GST_BUFFER_LIST_CAST (data), 0, 0)))
4064 caps = GST_BUFFER_CAPS (buf);
4071 /* this is the chain function that does not perform the additional argument
4072 * checking for that little extra speed.
4074 static inline GstFlowReturn
4075 gst_pad_chain_data_unchecked (GstPad * pad, gboolean is_buffer, void *data)
4078 gboolean caps_changed;
4080 gboolean emit_signal;
4082 GST_PAD_STREAM_LOCK (pad);
4084 GST_OBJECT_LOCK (pad);
4085 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4088 caps = gst_pad_data_get_caps (is_buffer, data);
4089 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4091 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4092 GST_OBJECT_UNLOCK (pad);
4094 /* see if the signal should be emited, we emit before caps nego as
4095 * we might drop the buffer and do capsnego for nothing. */
4096 if (G_UNLIKELY (emit_signal)) {
4097 if (G_LIKELY (is_buffer)) {
4098 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (data)))
4101 /* chain all groups in the buffer list one by one to avoid problems with
4102 * buffer probes that push buffers or events */
4107 /* we got a new datatype on the pad, see if it can handle it */
4108 if (G_UNLIKELY (caps_changed)) {
4109 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
4110 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
4111 goto not_negotiated;
4114 /* NOTE: we read the chainfunc unlocked.
4115 * we cannot hold the lock for the pad so we might send
4116 * the data to the wrong function. This is not really a
4117 * problem since functions are assigned at creation time
4118 * and don't change that often... */
4119 if (G_LIKELY (is_buffer)) {
4120 GstPadChainFunction chainfunc;
4122 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
4125 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4126 "calling chainfunction &%s", GST_DEBUG_FUNCPTR_NAME (chainfunc));
4128 ret = chainfunc (pad, GST_BUFFER_CAST (data));
4130 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4131 "called chainfunction &%s, returned %s",
4132 GST_DEBUG_FUNCPTR_NAME (chainfunc), gst_flow_get_name (ret));
4134 GstPadChainListFunction chainlistfunc;
4136 if (G_UNLIKELY ((chainlistfunc = GST_PAD_CHAINLISTFUNC (pad)) == NULL))
4139 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4140 "calling chainlistfunction &%s",
4141 GST_DEBUG_FUNCPTR_NAME (chainlistfunc));
4143 ret = chainlistfunc (pad, GST_BUFFER_LIST_CAST (data));
4145 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4146 "called chainlistfunction &%s, returned %s",
4147 GST_DEBUG_FUNCPTR_NAME (chainlistfunc), gst_flow_get_name (ret));
4150 GST_PAD_STREAM_UNLOCK (pad);
4156 GstBufferList *list;
4157 GstBufferListIterator *it;
4160 GST_PAD_STREAM_UNLOCK (pad);
4162 GST_INFO_OBJECT (pad, "chaining each group in list as a merged buffer");
4164 list = GST_BUFFER_LIST_CAST (data);
4165 it = gst_buffer_list_iterate (list);
4167 if (gst_buffer_list_iterator_next_group (it)) {
4169 group = gst_buffer_list_iterator_merge_group (it);
4170 if (group == NULL) {
4171 group = gst_buffer_new ();
4172 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining empty group");
4174 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining group");
4176 ret = gst_pad_chain_data_unchecked (pad, TRUE, group);
4177 } while (ret == GST_FLOW_OK && gst_buffer_list_iterator_next_group (it));
4179 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining empty group");
4180 ret = gst_pad_chain_data_unchecked (pad, TRUE, gst_buffer_new ());
4183 gst_buffer_list_iterator_free (it);
4184 gst_buffer_list_unref (list);
4192 gst_pad_data_unref (is_buffer, data);
4193 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4194 "pushing, but pad was flushing");
4195 GST_OBJECT_UNLOCK (pad);
4196 GST_PAD_STREAM_UNLOCK (pad);
4197 return GST_FLOW_WRONG_STATE;
4201 gst_pad_data_unref (is_buffer, data);
4202 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
4203 GST_PAD_STREAM_UNLOCK (pad);
4208 gst_pad_data_unref (is_buffer, data);
4209 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4210 "pushing data but pad did not accept");
4211 GST_PAD_STREAM_UNLOCK (pad);
4212 return GST_FLOW_NOT_NEGOTIATED;
4216 gst_pad_data_unref (is_buffer, data);
4217 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4218 "pushing, but not chainhandler");
4219 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
4220 ("push on pad %s:%s but it has no chainfunction",
4221 GST_DEBUG_PAD_NAME (pad)));
4222 GST_PAD_STREAM_UNLOCK (pad);
4223 return GST_FLOW_NOT_SUPPORTED;
4229 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4230 * @buffer: the #GstBuffer to send, return GST_FLOW_ERROR if not.
4232 * Chain a buffer to @pad.
4234 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
4236 * If the caps on @buffer are different from the current caps on @pad, this
4237 * function will call any setcaps function (see gst_pad_set_setcaps_function())
4238 * installed on @pad. If the new caps are not acceptable for @pad, this
4239 * function returns #GST_FLOW_NOT_NEGOTIATED.
4241 * The function proceeds calling the chain function installed on @pad (see
4242 * gst_pad_set_chain_function()) and the return value of that function is
4243 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
4246 * In all cases, success or failure, the caller loses its reference to @buffer
4247 * after calling this function.
4249 * Returns: a #GstFlowReturn from the pad.
4254 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
4256 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4257 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4258 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
4260 return gst_pad_chain_data_unchecked (pad, TRUE, buffer);
4264 * gst_pad_chain_list:
4265 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4266 * @list: the #GstBufferList to send, return GST_FLOW_ERROR if not.
4268 * Chain a bufferlist to @pad.
4270 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
4272 * If the caps on the first buffer of @list are different from the current
4273 * caps on @pad, this function will call any setcaps function
4274 * (see gst_pad_set_setcaps_function()) installed on @pad. If the new caps
4275 * are not acceptable for @pad, this function returns #GST_FLOW_NOT_NEGOTIATED.
4277 * The function proceeds calling the chainlist function installed on @pad (see
4278 * gst_pad_set_chain_list_function()) and the return value of that function is
4279 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
4280 * chainlist function.
4282 * In all cases, success or failure, the caller loses its reference to @list
4283 * after calling this function.
4287 * Returns: a #GstFlowReturn from the pad.
4292 gst_pad_chain_list (GstPad * pad, GstBufferList * list)
4294 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4295 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4296 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
4298 return gst_pad_chain_data_unchecked (pad, FALSE, list);
4301 static GstFlowReturn
4302 gst_pad_push_data (GstPad * pad, gboolean is_buffer, void *data)
4307 gboolean caps_changed;
4309 GST_OBJECT_LOCK (pad);
4311 /* FIXME: this check can go away; pad_set_blocked could be implemented with
4312 * probes completely or probes with an extended pad block. */
4313 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
4314 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
4317 /* we emit signals on the pad arg, the peer will have a chance to
4318 * emit in the _chain() function */
4319 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
4320 /* unlock before emitting */
4321 GST_OBJECT_UNLOCK (pad);
4323 if (G_LIKELY (is_buffer)) {
4324 /* if the signal handler returned FALSE, it means we should just drop the
4326 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (data)))
4329 /* push all buffers in the list */
4332 GST_OBJECT_LOCK (pad);
4335 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4338 /* Before pushing the buffer to the peer pad, ensure that caps
4339 * are set on this pad */
4340 caps = gst_pad_data_get_caps (is_buffer, data);
4341 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4343 /* take ref to peer pad before releasing the lock */
4344 gst_object_ref (peer);
4346 GST_OBJECT_UNLOCK (pad);
4348 /* we got a new datatype from the pad, it had better handle it */
4349 if (G_UNLIKELY (caps_changed)) {
4350 GST_DEBUG_OBJECT (pad,
4351 "caps changed from %" GST_PTR_FORMAT " to %p %" GST_PTR_FORMAT,
4352 GST_PAD_CAPS (pad), caps, caps);
4353 if (G_UNLIKELY (!gst_pad_set_caps (pad, caps)))
4354 goto not_negotiated;
4357 ret = gst_pad_chain_data_unchecked (peer, is_buffer, data);
4359 gst_object_unref (peer);
4365 GstBufferList *list;
4366 GstBufferListIterator *it;
4369 GST_INFO_OBJECT (pad, "pushing each group in list as a merged buffer");
4371 list = GST_BUFFER_LIST_CAST (data);
4372 it = gst_buffer_list_iterate (list);
4374 if (gst_buffer_list_iterator_next_group (it)) {
4376 group = gst_buffer_list_iterator_merge_group (it);
4377 if (group == NULL) {
4378 group = gst_buffer_new ();
4379 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing empty group");
4381 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing group");
4383 ret = gst_pad_push_data (pad, TRUE, group);
4384 } while (ret == GST_FLOW_OK && gst_buffer_list_iterator_next_group (it));
4386 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing empty group");
4387 ret = gst_pad_push_data (pad, TRUE, gst_buffer_new ());
4390 gst_buffer_list_iterator_free (it);
4391 gst_buffer_list_unref (list);
4396 /* ERROR recovery here */
4399 gst_pad_data_unref (is_buffer, data);
4400 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
4401 GST_OBJECT_UNLOCK (pad);
4406 gst_pad_data_unref (is_buffer, data);
4407 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
4412 gst_pad_data_unref (is_buffer, data);
4413 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4414 "pushing, but it was not linked");
4415 GST_OBJECT_UNLOCK (pad);
4416 return GST_FLOW_NOT_LINKED;
4420 gst_pad_data_unref (is_buffer, data);
4421 gst_object_unref (peer);
4422 GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
4423 "element pushed data then refused to accept the caps");
4424 return GST_FLOW_NOT_NEGOTIATED;
4430 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
4431 * @buffer: the #GstBuffer to push returns GST_FLOW_ERROR if not.
4433 * Pushes a buffer to the peer of @pad.
4435 * This function will call an installed pad block before triggering any
4436 * installed pad probes.
4438 * If the caps on @buffer are different from the currently configured caps on
4439 * @pad, this function will call any installed setcaps function on @pad (see
4440 * gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
4441 * format, this function returns #GST_FLOW_NOT_NEGOTIATED.
4443 * The function proceeds calling gst_pad_chain() on the peer pad and returns
4444 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
4447 * In all cases, success or failure, the caller loses its reference to @buffer
4448 * after calling this function.
4450 * Returns: a #GstFlowReturn from the peer pad.
4455 gst_pad_push (GstPad * pad, GstBuffer * buffer)
4457 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4458 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4459 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
4461 return gst_pad_push_data (pad, TRUE, buffer);
4465 * gst_pad_push_list:
4466 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
4467 * @list: the #GstBufferList to push returns GST_FLOW_ERROR if not.
4469 * Pushes a buffer list to the peer of @pad.
4471 * This function will call an installed pad block before triggering any
4472 * installed pad probes.
4474 * If the caps on the first buffer in the first group of @list are different
4475 * from the currently configured caps on @pad, this function will call any
4476 * installed setcaps function on @pad (see gst_pad_set_setcaps_function()). In
4477 * case of failure to renegotiate the new format, this function returns
4478 * #GST_FLOW_NOT_NEGOTIATED.
4480 * If there are any probes installed on @pad every group of the buffer list
4481 * will be merged into a normal #GstBuffer and pushed via gst_pad_push and the
4482 * buffer list will be unreffed.
4484 * The function proceeds calling the chain function on the peer pad and returns
4485 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
4486 * be returned. If the peer pad does not have any installed chainlist function
4487 * every group buffer of the list will be merged into a normal #GstBuffer and
4488 * chained via gst_pad_chain().
4490 * In all cases, success or failure, the caller loses its reference to @list
4491 * after calling this function.
4493 * Returns: a #GstFlowReturn from the peer pad.
4500 gst_pad_push_list (GstPad * pad, GstBufferList * list)
4502 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4503 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4504 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
4506 return gst_pad_push_data (pad, FALSE, list);
4510 * gst_pad_check_pull_range:
4511 * @pad: a sink #GstPad.
4513 * Checks if a gst_pad_pull_range() can be performed on the peer
4514 * source pad. This function is used by plugins that want to check
4515 * if they can use random access on the peer source pad.
4517 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
4518 * if it needs to perform some logic to determine if pull_range is
4521 * Returns: a gboolean with the result.
4526 gst_pad_check_pull_range (GstPad * pad)
4530 GstPadCheckGetRangeFunction checkgetrangefunc;
4532 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4534 GST_OBJECT_LOCK (pad);
4535 if (!GST_PAD_IS_SINK (pad))
4536 goto wrong_direction;
4538 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4541 gst_object_ref (peer);
4542 GST_OBJECT_UNLOCK (pad);
4544 /* see note in above function */
4545 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
4546 /* FIXME, kindoff ghetto */
4547 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
4548 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4549 "no checkgetrangefunc, assuming %d", ret);
4551 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4552 "calling checkgetrangefunc %s of peer pad %s:%s",
4553 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
4555 ret = checkgetrangefunc (peer);
4558 gst_object_unref (peer);
4562 /* ERROR recovery here */
4565 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4566 "checking pull range, but pad must be a sinkpad");
4567 GST_OBJECT_UNLOCK (pad);
4572 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4573 "checking pull range, but it was not linked");
4574 GST_OBJECT_UNLOCK (pad);
4580 * gst_pad_get_range:
4581 * @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
4582 * @offset: The start offset of the buffer
4583 * @size: The length of the buffer
4584 * @buffer: a pointer to hold the #GstBuffer, returns #GST_FLOW_ERROR if %NULL.
4586 * When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
4587 * immediatly and @buffer is %NULL.
4589 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
4590 * description of a getrange function. If @pad has no getrange function
4591 * installed (see gst_pad_set_getrange_function()) this function returns
4592 * #GST_FLOW_NOT_SUPPORTED.
4594 * This is a lowlevel function. Usualy gst_pad_pull_range() is used.
4596 * Returns: a #GstFlowReturn from the pad.
4601 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
4602 GstBuffer ** buffer)
4605 GstPadGetRangeFunction getrangefunc;
4606 gboolean emit_signal;
4608 gboolean caps_changed;
4610 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4611 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4612 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
4614 GST_PAD_STREAM_LOCK (pad);
4616 GST_OBJECT_LOCK (pad);
4617 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4620 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4621 GST_OBJECT_UNLOCK (pad);
4623 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
4626 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4627 "calling getrangefunc %s, offset %"
4628 G_GUINT64_FORMAT ", size %u",
4629 GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
4631 ret = getrangefunc (pad, offset, size, buffer);
4633 /* can only fire the signal if we have a valid buffer */
4634 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
4635 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
4639 GST_PAD_STREAM_UNLOCK (pad);
4641 if (G_UNLIKELY (ret != GST_FLOW_OK))
4642 goto get_range_failed;
4644 GST_OBJECT_LOCK (pad);
4645 /* Before pushing the buffer to the peer pad, ensure that caps
4646 * are set on this pad */
4647 caps = GST_BUFFER_CAPS (*buffer);
4648 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4649 GST_OBJECT_UNLOCK (pad);
4651 if (G_UNLIKELY (caps_changed)) {
4652 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
4653 /* this should usually work because the element produced the buffer */
4654 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
4655 goto not_negotiated;
4662 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4663 "pulling range, but pad was flushing");
4664 GST_OBJECT_UNLOCK (pad);
4665 GST_PAD_STREAM_UNLOCK (pad);
4666 return GST_FLOW_WRONG_STATE;
4670 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
4671 ("pullrange on pad %s:%s but it has no getrangefunction",
4672 GST_DEBUG_PAD_NAME (pad)));
4673 GST_PAD_STREAM_UNLOCK (pad);
4674 return GST_FLOW_NOT_SUPPORTED;
4678 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4679 "Dropping data after FALSE probe return");
4680 GST_PAD_STREAM_UNLOCK (pad);
4681 gst_buffer_unref (*buffer);
4683 return GST_FLOW_UNEXPECTED;
4688 GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
4689 (ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
4690 pad, "getrange failed, flow: %s", gst_flow_get_name (ret));
4695 gst_buffer_unref (*buffer);
4697 GST_CAT_WARNING_OBJECT (GST_CAT_SCHEDULING, pad,
4698 "getrange returned buffer of unaccaptable caps");
4699 return GST_FLOW_NOT_NEGOTIATED;
4705 * gst_pad_pull_range:
4706 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4707 * @offset: The start offset of the buffer
4708 * @size: The length of the buffer
4709 * @buffer: a pointer to hold the #GstBuffer, returns GST_FLOW_ERROR if %NULL.
4711 * Pulls a @buffer from the peer pad.
4713 * This function will first trigger the pad block signal if it was
4716 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
4717 * function returns the result of gst_pad_get_range() on the peer pad.
4718 * See gst_pad_get_range() for a list of return values and for the
4719 * semantics of the arguments of this function.
4721 * @buffer's caps must either be unset or the same as what is already
4722 * configured on @pad. Renegotiation within a running pull-mode pipeline is not
4725 * Returns: a #GstFlowReturn from the peer pad.
4726 * When this function returns #GST_FLOW_OK, @buffer will contain a valid
4727 * #GstBuffer that should be freed with gst_buffer_unref() after usage.
4728 * @buffer may not be used or freed when any other return value than
4729 * #GST_FLOW_OK is returned.
4734 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
4735 GstBuffer ** buffer)
4739 gboolean emit_signal;
4741 gboolean caps_changed;
4743 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4744 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4745 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
4747 GST_OBJECT_LOCK (pad);
4749 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
4750 handle_pad_block (pad);
4752 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4755 /* signal emision for the pad, peer has chance to emit when
4756 * we call _get_range() */
4757 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4759 gst_object_ref (peer);
4760 GST_OBJECT_UNLOCK (pad);
4762 ret = gst_pad_get_range (peer, offset, size, buffer);
4764 gst_object_unref (peer);
4766 if (G_UNLIKELY (ret != GST_FLOW_OK))
4767 goto pull_range_failed;
4769 /* can only fire the signal if we have a valid buffer */
4770 if (G_UNLIKELY (emit_signal)) {
4771 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
4775 GST_OBJECT_LOCK (pad);
4776 /* Before pushing the buffer to the peer pad, ensure that caps
4777 * are set on this pad */
4778 caps = GST_BUFFER_CAPS (*buffer);
4779 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4780 GST_OBJECT_UNLOCK (pad);
4782 /* we got a new datatype on the pad, see if it can handle it */
4783 if (G_UNLIKELY (caps_changed)) {
4784 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
4785 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
4786 goto not_negotiated;
4790 /* ERROR recovery here */
4793 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4794 "pulling range, but it was not linked");
4795 GST_OBJECT_UNLOCK (pad);
4796 return GST_FLOW_NOT_LINKED;
4801 GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
4802 (ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
4803 pad, "pullrange failed, flow: %s", gst_flow_get_name (ret));
4808 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4809 "Dropping data after FALSE probe return");
4810 gst_buffer_unref (*buffer);
4812 return GST_FLOW_UNEXPECTED;
4816 gst_buffer_unref (*buffer);
4818 GST_CAT_WARNING_OBJECT (GST_CAT_SCHEDULING, pad,
4819 "pullrange returned buffer of different caps");
4820 return GST_FLOW_NOT_NEGOTIATED;
4825 * gst_pad_push_event:
4826 * @pad: a #GstPad to push the event to.
4827 * @event: the #GstEvent to send to the pad.
4829 * Sends the event to the peer of the given pad. This function is
4830 * mainly used by elements to send events to their peer
4833 * This function takes owership of the provided event so you should
4834 * gst_event_ref() it if you want to reuse the event after this call.
4836 * Returns: TRUE if the event was handled.
4841 gst_pad_push_event (GstPad * pad, GstEvent * event)
4846 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4847 g_return_val_if_fail (event != NULL, FALSE);
4848 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
4850 GST_LOG_OBJECT (pad, "event: %s", GST_EVENT_TYPE_NAME (event));
4852 GST_OBJECT_LOCK (pad);
4854 /* Two checks to be made:
4855 * . (un)set the FLUSHING flag for flushing events,
4856 * . handle pad blocking */
4857 switch (GST_EVENT_TYPE (event)) {
4858 case GST_EVENT_FLUSH_START:
4859 GST_PAD_SET_FLUSHING (pad);
4861 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
4862 /* flush start will have set the FLUSHING flag and will then
4863 * unlock all threads doing a GCond wait on the blocking pad. This
4864 * will typically unblock the STREAMING thread blocked on a pad. */
4865 GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-start, "
4866 "doing block signal.");
4867 GST_PAD_BLOCK_BROADCAST (pad);
4871 case GST_EVENT_FLUSH_STOP:
4872 GST_PAD_UNSET_FLUSHING (pad);
4874 /* if we are blocked, flush away the FLUSH_STOP event */
4875 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
4876 GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-stop");
4881 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
4882 /* block the event as long as the pad is blocked */
4883 if (handle_pad_block (pad) != GST_FLOW_OK)
4889 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
4890 GST_OBJECT_UNLOCK (pad);
4892 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
4895 GST_OBJECT_LOCK (pad);
4897 peerpad = GST_PAD_PEER (pad);
4898 if (peerpad == NULL)
4901 GST_LOG_OBJECT (pad, "sending event %s to peerpad %" GST_PTR_FORMAT,
4902 GST_EVENT_TYPE_NAME (event), peerpad);
4903 gst_object_ref (peerpad);
4904 GST_OBJECT_UNLOCK (pad);
4906 result = gst_pad_send_event (peerpad, event);
4908 /* Note: we gave away ownership of the event at this point */
4909 GST_LOG_OBJECT (pad, "sent event to peerpad %" GST_PTR_FORMAT ", result %d",
4911 gst_object_unref (peerpad);
4915 /* ERROR handling */
4918 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
4919 gst_event_unref (event);
4924 GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
4925 gst_event_unref (event);
4926 GST_OBJECT_UNLOCK (pad);
4931 GST_DEBUG_OBJECT (pad,
4932 "Not forwarding event since we're flushing and blocking");
4933 gst_event_unref (event);
4934 GST_OBJECT_UNLOCK (pad);
4940 * gst_pad_send_event:
4941 * @pad: a #GstPad to send the event to.
4942 * @event: the #GstEvent to send to the pad.
4944 * Sends the event to the pad. This function can be used
4945 * by applications to send events in the pipeline.
4947 * If @pad is a source pad, @event should be an upstream event. If @pad is a
4948 * sink pad, @event should be a downstream event. For example, you would not
4949 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
4950 * Furthermore, some downstream events have to be serialized with data flow,
4951 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
4952 * the event needs to be serialized with data flow, this function will take the
4953 * pad's stream lock while calling its event function.
4955 * To find out whether an event type is upstream, downstream, or downstream and
4956 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
4957 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
4958 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or
4959 * plugin doesn't need to bother itself with this information; the core handles
4960 * all necessary locks and checks.
4962 * This function takes owership of the provided event so you should
4963 * gst_event_ref() it if you want to reuse the event after this call.
4965 * Returns: TRUE if the event was handled.
4968 gst_pad_send_event (GstPad * pad, GstEvent * event)
4970 gboolean result = FALSE;
4971 GstPadEventFunction eventfunc;
4972 gboolean serialized, need_unlock = FALSE;
4974 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4975 g_return_val_if_fail (event != NULL, FALSE);
4977 GST_OBJECT_LOCK (pad);
4978 if (GST_PAD_IS_SINK (pad)) {
4979 if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
4980 goto wrong_direction;
4981 serialized = GST_EVENT_IS_SERIALIZED (event);
4982 } else if (GST_PAD_IS_SRC (pad)) {
4983 if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
4984 goto wrong_direction;
4985 /* events on srcpad never are serialized */
4988 goto unknown_direction;
4990 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
4991 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
4992 GST_EVENT_SRC (event) = gst_object_ref (pad);
4996 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
4997 GST_OBJECT_UNLOCK (pad);
4999 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
5002 GST_OBJECT_LOCK (pad);
5005 switch (GST_EVENT_TYPE (event)) {
5006 case GST_EVENT_FLUSH_START:
5007 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
5008 "have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
5010 /* can't even accept a flush begin event when flushing */
5011 if (GST_PAD_IS_FLUSHING (pad))
5013 GST_PAD_SET_FLUSHING (pad);
5014 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
5016 case GST_EVENT_FLUSH_STOP:
5017 GST_PAD_UNSET_FLUSHING (pad);
5018 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
5019 GST_OBJECT_UNLOCK (pad);
5020 /* grab stream lock */
5021 GST_PAD_STREAM_LOCK (pad);
5023 GST_OBJECT_LOCK (pad);
5026 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
5027 GST_EVENT_TYPE_NAME (event));
5029 /* make this a little faster, no point in grabbing the lock
5030 * if the pad is allready flushing. */
5031 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
5035 /* lock order: STREAM_LOCK, LOCK, recheck flushing. */
5036 GST_OBJECT_UNLOCK (pad);
5037 GST_PAD_STREAM_LOCK (pad);
5039 GST_OBJECT_LOCK (pad);
5040 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
5045 if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
5048 GST_OBJECT_UNLOCK (pad);
5050 result = eventfunc (pad, event);
5053 GST_PAD_STREAM_UNLOCK (pad);
5055 GST_DEBUG_OBJECT (pad, "sent event, result %d", result);
5059 /* ERROR handling */
5062 g_warning ("pad %s:%s sending %s event in wrong direction",
5063 GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
5064 GST_OBJECT_UNLOCK (pad);
5065 gst_event_unref (event);
5070 g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
5071 GST_OBJECT_UNLOCK (pad);
5072 gst_event_unref (event);
5077 g_warning ("pad %s:%s has no event handler, file a bug.",
5078 GST_DEBUG_PAD_NAME (pad));
5079 GST_OBJECT_UNLOCK (pad);
5081 GST_PAD_STREAM_UNLOCK (pad);
5082 gst_event_unref (event);
5087 GST_OBJECT_UNLOCK (pad);
5089 GST_PAD_STREAM_UNLOCK (pad);
5090 GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
5091 "Received event on flushing pad. Discarding");
5092 gst_event_unref (event);
5097 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
5098 gst_event_unref (event);
5104 * gst_pad_set_element_private:
5105 * @pad: the #GstPad to set the private data of.
5106 * @priv: The private data to attach to the pad.
5108 * Set the given private data gpointer on the pad.
5109 * This function can only be used by the element that owns the pad.
5110 * No locking is performed in this function.
5113 gst_pad_set_element_private (GstPad * pad, gpointer priv)
5115 pad->element_private = priv;
5119 * gst_pad_get_element_private:
5120 * @pad: the #GstPad to get the private data of.
5122 * Gets the private data of a pad.
5123 * No locking is performed in this function.
5125 * Returns: a #gpointer to the private data.
5128 gst_pad_get_element_private (GstPad * pad)
5130 return pad->element_private;
5134 do_stream_status (GstPad * pad, GstStreamStatusType type,
5135 GThread * thread, GstTask * task)
5139 GST_DEBUG_OBJECT (pad, "doing stream-status %d", type);
5141 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (pad)))) {
5142 if (GST_IS_ELEMENT (parent)) {
5143 GstMessage *message;
5144 GValue value = { 0 };
5146 if (type == GST_STREAM_STATUS_TYPE_ENTER) {
5147 gchar *tname, *ename, *pname;
5149 /* create a good task name */
5150 ename = gst_element_get_name (parent);
5151 pname = gst_pad_get_name (pad);
5152 tname = g_strdup_printf ("%s:%s", ename, pname);
5156 gst_object_set_name (GST_OBJECT_CAST (task), tname);
5160 message = gst_message_new_stream_status (GST_OBJECT_CAST (pad),
5163 g_value_init (&value, GST_TYPE_TASK);
5164 g_value_set_object (&value, task);
5165 gst_message_set_stream_status_object (message, &value);
5166 g_value_unset (&value);
5168 GST_DEBUG_OBJECT (pad, "posting stream-status %d", type);
5169 gst_element_post_message (parent, message);
5171 gst_object_unref (parent);
5176 pad_enter_thread (GstTask * task, GThread * thread, gpointer user_data)
5178 do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_ENTER,
5183 pad_leave_thread (GstTask * task, GThread * thread, gpointer user_data)
5185 do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_LEAVE,
5189 static GstTaskThreadCallbacks thr_callbacks = {
5195 * gst_pad_start_task:
5196 * @pad: the #GstPad to start the task of
5197 * @func: the task function to call
5198 * @data: data passed to the task function
5200 * Starts a task that repeatedly calls @func with @data. This function
5201 * is mostly used in pad activation functions to start the dataflow.
5202 * The #GST_PAD_STREAM_LOCK of @pad will automatically be acquired
5203 * before @func is called.
5205 * Returns: a %TRUE if the task could be started.
5208 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
5213 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5214 g_return_val_if_fail (func != NULL, FALSE);
5216 GST_DEBUG_OBJECT (pad, "start task");
5218 GST_OBJECT_LOCK (pad);
5219 task = GST_PAD_TASK (pad);
5221 task = gst_task_create (func, data);
5222 gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
5223 gst_task_set_thread_callbacks (task, &thr_callbacks, pad, NULL);
5224 GST_DEBUG_OBJECT (pad, "created task");
5225 GST_PAD_TASK (pad) = task;
5226 gst_object_ref (task);
5227 /* release lock to post the message */
5228 GST_OBJECT_UNLOCK (pad);
5230 do_stream_status (pad, GST_STREAM_STATUS_TYPE_CREATE, NULL, task);
5232 gst_object_unref (task);
5234 GST_OBJECT_LOCK (pad);
5235 /* nobody else is supposed to have changed the pad now */
5236 if (GST_PAD_TASK (pad) != task)
5237 goto concurrent_stop;
5239 res = gst_task_set_state (task, GST_TASK_STARTED);
5240 GST_OBJECT_UNLOCK (pad);
5247 GST_OBJECT_UNLOCK (pad);
5253 * gst_pad_pause_task:
5254 * @pad: the #GstPad to pause the task of
5256 * Pause the task of @pad. This function will also wait until the
5257 * function executed by the task is finished if this function is not
5258 * called from the task function.
5260 * Returns: a TRUE if the task could be paused or FALSE when the pad
5264 gst_pad_pause_task (GstPad * pad)
5269 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5271 GST_DEBUG_OBJECT (pad, "pause task");
5273 GST_OBJECT_LOCK (pad);
5274 task = GST_PAD_TASK (pad);
5277 res = gst_task_set_state (task, GST_TASK_PAUSED);
5278 GST_OBJECT_UNLOCK (pad);
5280 /* wait for task function to finish, this lock is recursive so it does nothing
5281 * when the pause is called from the task itself */
5282 GST_PAD_STREAM_LOCK (pad);
5283 GST_PAD_STREAM_UNLOCK (pad);
5289 GST_DEBUG_OBJECT (pad, "pad has no task");
5290 GST_OBJECT_UNLOCK (pad);
5296 * gst_pad_stop_task:
5297 * @pad: the #GstPad to stop the task of
5299 * Stop the task of @pad. This function will also make sure that the
5300 * function executed by the task will effectively stop if not called
5301 * from the GstTaskFunction.
5303 * This function will deadlock if called from the GstTaskFunction of
5304 * the task. Use gst_task_pause() instead.
5306 * Regardless of whether the pad has a task, the stream lock is acquired and
5307 * released so as to ensure that streaming through this pad has finished.
5309 * Returns: a TRUE if the task could be stopped or FALSE on error.
5312 gst_pad_stop_task (GstPad * pad)
5317 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5319 GST_DEBUG_OBJECT (pad, "stop task");
5321 GST_OBJECT_LOCK (pad);
5322 task = GST_PAD_TASK (pad);
5325 GST_PAD_TASK (pad) = NULL;
5326 res = gst_task_set_state (task, GST_TASK_STOPPED);
5327 GST_OBJECT_UNLOCK (pad);
5329 GST_PAD_STREAM_LOCK (pad);
5330 GST_PAD_STREAM_UNLOCK (pad);
5332 if (!gst_task_join (task))
5335 gst_object_unref (task);
5341 GST_DEBUG_OBJECT (pad, "no task");
5342 GST_OBJECT_UNLOCK (pad);
5344 GST_PAD_STREAM_LOCK (pad);
5345 GST_PAD_STREAM_UNLOCK (pad);
5347 /* this is not an error */
5352 /* this is bad, possibly the application tried to join the task from
5353 * the task's thread. We install the task again so that it will be stopped
5354 * again from the right thread next time hopefully. */
5355 GST_OBJECT_LOCK (pad);
5356 GST_DEBUG_OBJECT (pad, "join failed");
5357 /* we can only install this task if there was no other task */
5358 if (GST_PAD_TASK (pad) == NULL)
5359 GST_PAD_TASK (pad) = task;
5360 GST_OBJECT_UNLOCK (pad);