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 other elements
25 * @see_also: #GstPadTemplate, #GstElement, #GstEvent
27 * A #GstElement is linked to other elements via "pads", which are extremely
28 * light-weight generic link points.
29 * After two pads are retrieved from an element with gst_element_get_pad(),
30 * the pads can be link with gst_pad_link(). (For quick links,
31 * you can also use gst_element_link(), which will make the obvious
32 * link for you if it's straightforward.)
34 * Pads are typically created from a #GstPadTemplate with
35 * gst_pad_new_from_template().
37 * Pads have #GstCaps attached to it to describe the media type they are capable
39 * gst_pad_get_caps() and gst_pad_try_set_caps() are used to manipulate the caps
41 * Pads created from a pad template cannot set capabilities that are
42 * incompatible with the pad template capabilities.
44 * Pads without pad templates can be created with gst_pad_new(),
45 * which takes a direction and a name as an argument. If the name is NULL,
46 * then a guaranteed unique name will be assigned to it.
48 * gst_pad_get_parent() will retrieve the #GstElement that owns the pad.
50 * A #GstElement creating a pad will typically use the various
51 * gst_pad_set_*_function() calls to register callbacks for various events
54 * GstElements will use gst_pad_push() and gst_pad_pull() to push out
55 * or pull in a buffer.
56 * gst_pad_select() and gst_pad_selectv() are used by plugins to wait for the
57 * first incoming buffer or event on any of the given set of pads.
59 * To send a #GstEvent on a pad, use gst_pad_send_event().
61 * Last reviewed on December 13th, 2002 (0.5.0.1)
64 #include "gst_private.h"
67 #include "gstpadtemplate.h"
68 #include "gstenumtypes.h"
69 #include "gstmarshal.h"
75 GST_DEBUG_CATEGORY_STATIC (debug_dataflow);
76 #define DEBUG_DATA(obj,data,notice) G_STMT_START{\
78 GST_CAT_DEBUG_OBJECT (debug_dataflow, obj, "NULL data value"); \
79 } else if (GST_IS_EVENT (data)) { \
80 GST_CAT_DEBUG_OBJECT (debug_dataflow, obj, "%s event %p (type %d, refcount %d)", notice, data, \
81 GST_EVENT_TYPE (data), GST_DATA_REFCOUNT_VALUE (data)); \
83 GST_CAT_LOG_OBJECT (debug_dataflow, obj, "%s buffer %p (size %u, refcount %d)", notice, data, \
84 GST_BUFFER_SIZE (data), GST_BUFFER_REFCOUNT_VALUE (data)); \
87 #define GST_CAT_DEFAULT GST_CAT_PADS
89 /* Pad signals and args */
109 GType _gst_pad_type = 0;
111 static void gst_pad_class_init (GstPadClass * klass);
112 static void gst_pad_init (GstPad * pad);
113 static void gst_pad_dispose (GObject * object);
114 static void gst_pad_finalize (GObject * object);
115 static void gst_pad_set_property (GObject * object, guint prop_id,
116 const GValue * value, GParamSpec * pspec);
117 static void gst_pad_get_property (GObject * object, guint prop_id,
118 GValue * value, GParamSpec * pspec);
120 static void handle_pad_block (GstPad * pad);
121 static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
122 static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
123 static gboolean gst_pad_activate_default (GstPad * pad);
125 #ifndef GST_DISABLE_LOADSAVE
126 static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
129 static GstObjectClass *parent_class = NULL;
130 static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
132 static GQuark buffer_quark;
133 static GQuark event_quark;
136 gst_pad_get_type (void)
138 if (!_gst_pad_type) {
139 static const GTypeInfo pad_info = {
140 sizeof (GstPadClass), NULL, NULL,
141 (GClassInitFunc) gst_pad_class_init, NULL, NULL,
144 (GInstanceInitFunc) gst_pad_init, NULL
147 _gst_pad_type = g_type_register_static (GST_TYPE_OBJECT, "GstPad",
150 buffer_quark = g_quark_from_static_string ("buffer");
151 event_quark = g_quark_from_static_string ("event");
153 GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW",
154 GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads");
156 return _gst_pad_type;
160 _gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
161 GValue * return_accu, const GValue * handler_return, gpointer dummy)
163 gboolean ret = g_value_get_boolean (handler_return);
165 GST_DEBUG ("accumulated %d", ret);
166 g_value_set_boolean (return_accu, ret);
172 default_have_data (GstPad * pad, GstMiniObject * o)
178 gst_pad_class_init (GstPadClass * klass)
180 GObjectClass *gobject_class;
183 GstObjectClass *gstobject_class;
185 gobject_class = (GObjectClass *) klass;
186 gstobject_class = (GstObjectClass *) klass;
188 parent_class = g_type_class_ref (GST_TYPE_OBJECT);
190 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pad_dispose);
191 gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_pad_finalize);
192 gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pad_set_property);
193 gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pad_get_property);
197 * @pad: the pad that emitted the signal
198 * @peer: the peer pad that has been connected
200 * Signals that a pad has been linked to the peer pad.
202 gst_pad_signals[PAD_LINKED] =
203 g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
204 G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
205 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
208 * @pad: the pad that emitted the signal
209 * @peer: the peer pad that has been disconnected
211 * Signals that a pad has been unlinked from the peer pad.
213 gst_pad_signals[PAD_UNLINKED] =
214 g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
215 G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
216 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
218 * GstPad::request-link:
219 * @pad: the pad that emitted the signal
220 * @peer: the peer pad for which a connection is requested
222 * Signals that a pad connection has been requested.
224 gst_pad_signals[PAD_REQUEST_LINK] =
225 g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
226 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
227 NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
231 * @pad: the pad that emitted the signal
232 * @mini_obj: new data
234 * Signals that new data is available on the pad. This signal is used
235 * internally for implementing pad probes.
236 * See gst_pad_add_*_probe functions.
238 * Returns: %TRUE to keep the data, %FALSE to drop it
240 gst_pad_signals[PAD_HAVE_DATA] =
241 g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
242 G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
243 G_STRUCT_OFFSET (GstPadClass, have_data),
244 _gst_do_pass_data_accumulator,
245 NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
246 GST_TYPE_MINI_OBJECT);
248 g_object_class_install_property (G_OBJECT_CLASS (klass), PAD_PROP_CAPS,
249 g_param_spec_boxed ("caps", "Caps", "The capabilities of the pad",
250 GST_TYPE_CAPS, G_PARAM_READABLE));
251 g_object_class_install_property (G_OBJECT_CLASS (klass), PAD_PROP_DIRECTION,
252 g_param_spec_enum ("direction", "Direction", "The direction of the pad",
253 GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
254 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
255 g_object_class_install_property (G_OBJECT_CLASS (klass), PAD_PROP_TEMPLATE,
256 g_param_spec_object ("template", "Template",
257 "The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
260 #ifndef GST_DISABLE_LOADSAVE
261 gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_pad_save_thyself);
263 gstobject_class->path_string_separator = ".";
265 klass->have_data = default_have_data;
269 gst_pad_init (GstPad * pad)
271 pad->direction = GST_PAD_UNKNOWN;
274 pad->chainfunc = NULL;
278 pad->linkfunc = NULL;
279 pad->getcapsfunc = NULL;
281 pad->activatefunc = gst_pad_activate_default;
282 pad->eventfunc = gst_pad_event_default;
283 pad->querytypefunc = gst_pad_get_query_types_default;
284 pad->queryfunc = gst_pad_query_default;
285 pad->intlinkfunc = gst_pad_get_internal_links_default;
287 pad->do_buffer_signals = 0;
288 pad->do_event_signals = 0;
290 GST_PAD_UNSET_FLUSHING (pad);
292 pad->preroll_lock = g_mutex_new ();
293 pad->preroll_cond = g_cond_new ();
295 pad->stream_rec_lock = g_new (GStaticRecMutex, 1);
296 g_static_rec_mutex_init (pad->stream_rec_lock);
298 pad->block_cond = g_cond_new ();
302 gst_pad_dispose (GObject * object)
304 GstPad *pad = GST_PAD (object);
306 GST_CAT_DEBUG (GST_CAT_REFCOUNTING, "dispose %s:%s",
307 GST_DEBUG_PAD_NAME (pad));
309 /* we don't hold a ref to the peer so we can just set the
311 GST_PAD_PEER (pad) = NULL;
314 gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
316 gst_pad_set_pad_template (pad, NULL);
318 G_OBJECT_CLASS (parent_class)->dispose (object);
322 gst_pad_finalize (GObject * object)
324 GstPad *pad = GST_PAD (object);
327 /* in case the task is still around, clean it up */
328 if ((task = GST_PAD_TASK (pad))) {
329 gst_task_join (task);
330 GST_PAD_TASK (pad) = NULL;
331 gst_object_unref (task);
334 if (pad->stream_rec_lock) {
335 g_static_rec_mutex_free (pad->stream_rec_lock);
336 g_free (pad->stream_rec_lock);
337 pad->stream_rec_lock = NULL;
339 if (pad->preroll_lock) {
340 g_mutex_free (pad->preroll_lock);
341 g_cond_free (pad->preroll_cond);
342 pad->preroll_lock = NULL;
343 pad->preroll_cond = NULL;
345 if (pad->block_cond) {
346 g_cond_free (pad->block_cond);
347 pad->block_cond = NULL;
350 G_OBJECT_CLASS (parent_class)->finalize (object);
354 gst_pad_set_property (GObject * object, guint prop_id,
355 const GValue * value, GParamSpec * pspec)
357 g_return_if_fail (GST_IS_PAD (object));
360 case PAD_PROP_DIRECTION:
361 GST_PAD_DIRECTION (object) = g_value_get_enum (value);
363 case PAD_PROP_TEMPLATE:
364 gst_pad_set_pad_template (GST_PAD_CAST (object),
365 (GstPadTemplate *) g_value_dup_object (value));
368 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
374 gst_pad_get_property (GObject * object, guint prop_id,
375 GValue * value, GParamSpec * pspec)
377 g_return_if_fail (GST_IS_PAD (object));
381 g_value_set_boxed (value, GST_PAD_CAPS (object));
383 case PAD_PROP_DIRECTION:
384 g_value_set_enum (value, GST_PAD_DIRECTION (object));
386 case PAD_PROP_TEMPLATE:
387 g_value_set_object (value, GST_PAD_TEMPLATE (object));
390 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
397 * @name: the name of the new pad.
398 * @direction: the #GstPadDirection of the pad.
400 * Creates a new pad with the given name in the given direction.
401 * If name is NULL, a guaranteed unique name (across all pads)
403 * This function makes a copy of the name so you can safely free the name.
405 * Returns: a new #GstPad, or NULL in case of an error.
410 gst_pad_new (const gchar * name, GstPadDirection direction)
412 return g_object_new (GST_TYPE_PAD,
413 "name", name, "direction", direction, NULL);
417 * gst_pad_new_from_template:
418 * @templ: the pad template to use
419 * @name: the name of the element
421 * Creates a new pad with the given name from the given template.
422 * If name is NULL, a guaranteed unique name (across all pads)
424 * This function makes a copy of the name so you can safely free the name.
426 * Returns: a new #GstPad, or NULL in case of an error.
429 gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
431 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
433 return g_object_new (GST_TYPE_PAD,
434 "name", name, "direction", templ->direction, "template", templ, NULL);
438 * gst_pad_get_direction:
439 * @pad: a #GstPad to get the direction of.
441 * Gets the direction of the pad. The direction of the pad is
442 * decided at construction time so this function does not take
445 * Returns: the #GstPadDirection of the pad.
450 gst_pad_get_direction (GstPad * pad)
452 GstPadDirection result;
454 /* PAD_UNKNOWN is a little silly but we need some sort of
455 * error return value */
456 g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
459 result = GST_PAD_DIRECTION (pad);
466 gst_pad_activate_default (GstPad * pad)
468 return gst_pad_activate_push (pad, TRUE);
472 pre_activate_switch (GstPad * pad, gboolean new_active)
478 GST_PAD_SET_FLUSHING (pad);
479 /* unlock blocked pads so element can resume and stop */
480 GST_PAD_BLOCK_SIGNAL (pad);
486 post_activate_switch (GstPad * pad, gboolean new_active)
490 GST_PAD_UNSET_FLUSHING (pad);
493 /* ensures that streaming stops */
494 GST_STREAM_LOCK (pad);
495 GST_STREAM_UNLOCK (pad);
500 * gst_pad_set_active:
501 * @pad: the #GstPad to activate or deactivate.
502 * @active: whether or not the pad should be active.
504 * Activates or deactivates the given pad. Must be called with the %GST_STATE_LOCK.
505 * Normally called from within core state change functions.
507 * If @active, makes sure the pad is active. If it is already active, either in
508 * push or pull mode, just return. Otherwise dispatches to the pad's activate
509 * function to perform the actual activation.
511 * If not @active, checks the pad's current mode and calls
512 * gst_pad_activate_push() or gst_pad_activate_pull(), as appropriate, with a
515 * Returns: TRUE if the operation was successfull.
517 * MT safe. Must be called with %GST_STATE_LOCK.
520 gst_pad_set_active (GstPad * pad, gboolean active)
523 gboolean ret = FALSE;
525 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
528 old = GST_PAD_ACTIVATE_MODE (pad);
533 case GST_ACTIVATE_PUSH:
534 case GST_ACTIVATE_PULL:
537 case GST_ACTIVATE_NONE:
538 ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
543 case GST_ACTIVATE_PUSH:
544 ret = gst_pad_activate_push (pad, FALSE);
546 case GST_ACTIVATE_PULL:
547 ret = gst_pad_activate_pull (pad, FALSE);
549 case GST_ACTIVATE_NONE:
559 * gst_pad_activate_pull:
560 * @pad: the #GstPad to activate or deactivate.
561 * @active: whether or not the pad should be active.
563 * Activates or deactivates the given pad in pull mode via dispatching to the
564 * pad's activatepullfunc. For use from within pad activation functions only.
565 * When called on sink pads, will first proxy the call to the peer pad, which is
566 * expected to activate its internally linked pads from within its activate_pull
569 * If you don't know what this is, you probably don't want to call it.
571 * Returns: TRUE if the operation was successfull.
576 gst_pad_activate_pull (GstPad * pad, gboolean active)
580 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
583 old = GST_PAD_ACTIVATE_MODE (pad);
586 if ((active && old == GST_ACTIVATE_PULL)
587 || (!active && old == GST_ACTIVATE_NONE))
591 g_return_val_if_fail (old == GST_ACTIVATE_NONE, FALSE);
593 g_return_val_if_fail (old == GST_ACTIVATE_PULL, FALSE);
596 if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
597 GstPad *peer = gst_pad_get_peer (pad);
600 if (!gst_pad_activate_pull (peer, active)) {
602 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
603 "activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
605 gst_object_unref (peer);
611 pre_activate_switch (pad, active);
613 if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
614 if (GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active)) {
620 /* can happen for sinks of passthrough elements */
626 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
627 active ? "activated" : "deactivated");
634 GST_PAD_ACTIVATE_MODE (pad) =
635 active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
637 post_activate_switch (pad, active);
639 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
640 active ? "activated" : "deactivated");
646 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
647 active ? "activate" : "deactivate");
653 * gst_pad_activate_push:
654 * @pad: the #GstPad to activate or deactivate.
655 * @active: whether or not the pad should be active.
657 * Activates or deactivates the given pad in push mode via dispatching to the
658 * pad's activatepushfunc. For use from within pad activation functions only.
660 * If you don't know what this is, you probably don't want to call it.
662 * Returns: TRUE if the operation was successfull.
667 gst_pad_activate_push (GstPad * pad, gboolean active)
671 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
672 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
673 active ? "activated" : "deactivated");
676 old = GST_PAD_ACTIVATE_MODE (pad);
679 if ((active && old == GST_ACTIVATE_PUSH)
680 || (!active && old == GST_ACTIVATE_NONE))
684 g_return_val_if_fail (old == GST_ACTIVATE_NONE, FALSE);
686 g_return_val_if_fail (old == GST_ACTIVATE_PUSH, FALSE);
689 pre_activate_switch (pad, active);
693 GST_STREAM_LOCK (pad);
695 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
696 if (GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active)) {
702 /* quite ok, element relies on state change func to prepare itself */
708 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
709 active ? "activated" : "deactivated");
716 GST_PAD_ACTIVATE_MODE (pad) =
717 active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
719 post_activate_switch (pad, active);
723 GST_STREAM_UNLOCK (pad);
725 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
726 active ? "activated" : "deactivated");
734 GST_STREAM_UNLOCK (pad);
736 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
737 active ? "activate" : "deactivate");
744 * @pad: the #GstPad to query
746 * Query if a pad is active
748 * Returns: TRUE if the pad is active.
753 gst_pad_is_active (GstPad * pad)
755 gboolean result = FALSE;
757 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
760 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
767 * gst_pad_set_blocked_async:
768 * @pad: the #GstPad to block or unblock
769 * @blocked: boolean indicating we should block or unblock
770 * @callback: #GstPadBlockCallback that will be called when the
771 * operation succeeds.
772 * @user_data: user data passed to the callback
774 * Blocks or unblocks the dataflow on a pad. The provided callback
775 * is called when the operation succeeds. This can take a while as
776 * the pad can only become blocked when real dataflow is happening.
777 * When the pipeline is stalled, for example in PAUSED, this can
778 * take an indeterminate amount of time.
779 * You can pass NULL as the callback to make this call block. Be
780 * carefull with this blocking call as it might not return for
781 * reasons stated above.
783 * Returns: TRUE if the pad could be blocked. This function can fail
784 * if wrong parameters were passed or the pad was already in the
790 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
791 GstPadBlockCallback callback, gpointer user_data)
793 gboolean was_blocked;
795 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
799 was_blocked = GST_PAD_IS_BLOCKED (pad);
801 if (G_UNLIKELY (was_blocked == blocked))
802 goto had_right_state;
805 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad %s:%s",
806 GST_DEBUG_PAD_NAME (pad));
808 GST_FLAG_SET (pad, GST_PAD_BLOCKED);
809 pad->block_callback = callback;
810 pad->block_data = user_data;
812 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
813 GST_PAD_BLOCK_WAIT (pad);
814 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
817 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad %s:%s",
818 GST_DEBUG_PAD_NAME (pad));
820 GST_FLAG_UNSET (pad, GST_PAD_BLOCKED);
822 pad->block_callback = callback;
823 pad->block_data = user_data;
826 GST_PAD_BLOCK_SIGNAL (pad);
828 GST_PAD_BLOCK_SIGNAL (pad);
829 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
830 GST_PAD_BLOCK_WAIT (pad);
831 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
840 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
841 "pad %s:%s was in right state", GST_DEBUG_PAD_NAME (pad));
848 * gst_pad_set_blocked:
849 * @pad: the #GstPad to block or unblock
850 * @blocked: boolean indicating we should block or unblock
852 * Blocks or unblocks the dataflow on a pad. This function is
853 * a shortcut for @gst_pad_set_blocked_async() with a NULL
856 * Returns: TRUE if the pad could be blocked. This function can fail
857 * wrong parameters were passed or the pad was already in the
863 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
865 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
869 * gst_pad_is_blocked:
870 * @pad: the #GstPad to query
872 * Checks if the pad is blocked or not. This function returns the
873 * last requested state of the pad. It is not certain that the pad
874 * is actually blocked at this point.
876 * Returns: TRUE if the pad is blocked.
881 gst_pad_is_blocked (GstPad * pad)
883 gboolean result = FALSE;
885 g_return_val_if_fail (GST_IS_PAD (pad), result);
888 result = GST_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
895 * gst_pad_set_activate_function:
896 * @pad: a sink #GstPad.
897 * @activate: the #GstPadActivateFunction to set.
899 * Sets the given activate function for the pad. The activate function will
900 * dispatch to activate_push or activate_pull to perform the actual activation.
901 * Only makes sense to set on sink pads.
903 * Call this function if your sink pad can start a pull-based task.
906 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
908 g_return_if_fail (GST_IS_PAD (pad));
910 GST_PAD_ACTIVATEFUNC (pad) = activate;
911 GST_CAT_DEBUG (GST_CAT_PADS, "activatefunc for %s:%s set to %s",
912 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activate));
916 * gst_pad_set_activatepull_function:
917 * @pad: a sink #GstPad.
918 * @activatepull: the #GstPadActivateModeFunction to set.
920 * Sets the given activate_pull function for the pad. An activate_pull function
921 * prepares the element and any upstream connections for pulling. See XXX
922 * part-activation.txt for details.
925 gst_pad_set_activatepull_function (GstPad * pad,
926 GstPadActivateModeFunction activatepull)
928 g_return_if_fail (GST_IS_PAD (pad));
930 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
931 GST_CAT_DEBUG (GST_CAT_PADS, "activatepullfunc for %s:%s set to %s",
932 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activatepull));
936 * gst_pad_set_activatepush_function:
937 * @pad: a sink #GstPad.
938 * @activatepush: the #GstPadActivateModeFunction to set.
940 * Sets the given activate_push function for the pad. An activate_push function
941 * prepares the element for pushing. See XXX part-activation.txt for details.
944 gst_pad_set_activatepush_function (GstPad * pad,
945 GstPadActivateModeFunction activatepush)
947 g_return_if_fail (GST_IS_PAD (pad));
949 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
950 GST_CAT_DEBUG (GST_CAT_PADS, "activatepushfunc for %s:%s set to %s",
951 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activatepush));
955 * gst_pad_set_chain_function:
956 * @pad: a sink #GstPad.
957 * @chain: the #GstPadChainFunction to set.
959 * Sets the given chain function for the pad. The chain function is called to
960 * process a #GstBuffer input buffer.
963 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
965 g_return_if_fail (GST_IS_PAD (pad));
966 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
968 GST_PAD_CHAINFUNC (pad) = chain;
969 GST_CAT_DEBUG (GST_CAT_PADS, "chainfunc for %s:%s set to %s",
970 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (chain));
974 * gst_pad_set_getrange_function:
975 * @pad: a source #GstPad.
976 * @get: the #GstPadGetRangeFunction to set.
978 * Sets the given getrange function for the pad. The getrange function is called to
979 * produce a new #GstBuffer to start the processing pipeline. Getrange functions cannot
983 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
985 g_return_if_fail (GST_IS_PAD (pad));
986 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
988 GST_PAD_GETRANGEFUNC (pad) = get;
990 GST_CAT_DEBUG (GST_CAT_PADS, "getrangefunc for %s:%s set to %s",
991 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (get));
995 * gst_pad_set_checkgetrange_function:
996 * @pad: a source #GstPad.
997 * @check: the #GstPadCheckGetRangeFunction to set.
999 * Sets the given checkgetrange function for the pad. Implement this function on
1000 * a pad if you dynamically support getrange based scheduling on the pad.
1003 gst_pad_set_checkgetrange_function (GstPad * pad,
1004 GstPadCheckGetRangeFunction check)
1006 g_return_if_fail (GST_IS_PAD (pad));
1007 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1009 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1011 GST_CAT_DEBUG (GST_CAT_PADS, "checkgetrangefunc for %s:%s set to %s",
1012 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (check));
1016 * gst_pad_set_event_function:
1017 * @pad: a source #GstPad.
1018 * @event: the #GstPadEventFunction to set.
1020 * Sets the given event handler for the pad.
1023 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1025 g_return_if_fail (GST_IS_PAD (pad));
1027 GST_PAD_EVENTFUNC (pad) = event;
1029 GST_CAT_DEBUG (GST_CAT_PADS, "eventfunc for %s:%s set to %s",
1030 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (event));
1034 * gst_pad_set_query_function:
1035 * @pad: a #GstPad of either direction.
1036 * @query: the #GstPadQueryFunction to set.
1038 * Set the given query function for the pad.
1041 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1043 g_return_if_fail (GST_IS_PAD (pad));
1045 GST_PAD_QUERYFUNC (pad) = query;
1047 GST_CAT_DEBUG (GST_CAT_PADS, "queryfunc for %s:%s set to %s",
1048 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (query));
1052 * gst_pad_set_query_type_function:
1053 * @pad: a #GstPad of either direction.
1054 * @type_func: the #GstPadQueryTypeFunction to set.
1056 * Set the given query type function for the pad.
1059 gst_pad_set_query_type_function (GstPad * pad,
1060 GstPadQueryTypeFunction type_func)
1062 g_return_if_fail (GST_IS_PAD (pad));
1064 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1066 GST_CAT_DEBUG (GST_CAT_PADS, "querytypefunc for %s:%s set to %s",
1067 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (type_func));
1071 * gst_pad_get_query_types:
1074 * Get an array of supported queries that can be performed
1077 * Returns: a zero-terminated array of #GstQueryType.
1079 const GstQueryType *
1080 gst_pad_get_query_types (GstPad * pad)
1082 GstPadQueryTypeFunction func;
1084 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1086 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1098 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1100 *data = gst_pad_get_query_types (pad);
1106 * gst_pad_get_query_types_default:
1109 * Invoke the default dispatcher for the query types on
1112 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1113 * internally-linked pads has a query types function.
1115 const GstQueryType *
1116 gst_pad_get_query_types_default (GstPad * pad)
1118 GstQueryType *result = NULL;
1120 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1122 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1123 gst_pad_get_query_types_dispatcher, &result);
1129 * gst_pad_set_internal_link_function:
1130 * @pad: a #GstPad of either direction.
1131 * @intlink: the #GstPadIntLinkFunction to set.
1133 * Sets the given internal link function for the pad.
1136 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1138 g_return_if_fail (GST_IS_PAD (pad));
1140 GST_PAD_INTLINKFUNC (pad) = intlink;
1141 GST_CAT_DEBUG (GST_CAT_PADS, "internal link for %s:%s set to %s",
1142 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (intlink));
1146 * gst_pad_set_link_function:
1148 * @link: the #GstPadLinkFunction to set.
1150 * Sets the given link function for the pad. It will be called when the pad is
1151 * linked or relinked with caps. The caps passed to the link function is
1152 * the caps for the connnection. It can contain a non fixed caps.
1154 * The return value GST_PAD_LINK_OK should be used when the connection can be
1157 * The return value GST_PAD_LINK_REFUSED should be used when the connection
1158 * cannot be made for some reason.
1161 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1163 g_return_if_fail (GST_IS_PAD (pad));
1165 GST_PAD_LINKFUNC (pad) = link;
1166 GST_CAT_DEBUG (GST_CAT_PADS, "linkfunc for %s:%s set to %s",
1167 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (link));
1171 * gst_pad_set_unlink_function:
1173 * @unlink: the #GstPadUnlinkFunction to set.
1175 * Sets the given unlink function for the pad. It will be called
1176 * when the pad is unlinked.
1179 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1181 g_return_if_fail (GST_IS_PAD (pad));
1183 GST_PAD_UNLINKFUNC (pad) = unlink;
1184 GST_CAT_DEBUG (GST_CAT_PADS, "unlinkfunc for %s:%s set to %s",
1185 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (unlink));
1189 * gst_pad_set_getcaps_function:
1191 * @getcaps: the #GstPadGetCapsFunction to set.
1193 * Sets the given getcaps function for the pad. @getcaps should return the
1194 * allowable caps for a pad in the context of the element's state, its link to
1195 * other elements, and the devices or files it has opened. These caps must be a
1196 * subset of the pad template caps. In the NULL state with no links, @getcaps
1197 * should ideally return the same caps as the pad template. In rare
1198 * circumstances, an object property can affect the caps returned by @getcaps,
1199 * but this is discouraged.
1201 * You do not need to call this function if @pad's allowed caps are always the
1202 * same as the pad template caps. This can only be true if the padtemplate
1203 * has fixed simple caps.
1205 * For most filters, the caps returned by @getcaps is directly affected by the
1206 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1207 * the srcpad's getcaps function is directly related to the stream data. Again,
1208 * @getcaps should return the most specific caps it reasonably can, since this
1209 * helps with autoplugging.
1211 * Note that the return value from @getcaps is owned by the caller, so the caller
1212 * should unref the caps after usage.
1215 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1217 g_return_if_fail (GST_IS_PAD (pad));
1219 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1220 GST_CAT_DEBUG (GST_CAT_PADS, "getcapsfunc for %s:%s set to %s",
1221 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (getcaps));
1225 * gst_pad_set_acceptcaps_function:
1227 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1229 * Sets the given acceptcaps function for the pad. The acceptcaps function
1230 * will be called to check if the pad can accept the given caps.
1233 gst_pad_set_acceptcaps_function (GstPad * pad,
1234 GstPadAcceptCapsFunction acceptcaps)
1236 g_return_if_fail (GST_IS_PAD (pad));
1238 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1239 GST_CAT_DEBUG (GST_CAT_PADS, "acceptcapsfunc for %s:%s set to %s",
1240 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1244 * gst_pad_set_fixatecaps_function:
1246 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1248 * Sets the given fixatecaps function for the pad. The fixatecaps function
1249 * will be called whenever the default values for a GstCaps needs to be
1253 gst_pad_set_fixatecaps_function (GstPad * pad,
1254 GstPadFixateCapsFunction fixatecaps)
1256 g_return_if_fail (GST_IS_PAD (pad));
1258 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1259 GST_CAT_DEBUG (GST_CAT_PADS, "fixatecapsfunc for %s:%s set to %s",
1260 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1264 * gst_pad_set_setcaps_function:
1266 * @setcaps: the #GstPadSetCapsFunction to set.
1268 * Sets the given setcaps function for the pad. The setcaps function
1269 * will be called whenever a buffer with a new media type is pushed or
1270 * pulled from the pad. The pad/element needs to update it's internal
1271 * structures to process the new media type. If this new type is not
1272 * acceptable, the setcaps function should return FALSE.
1275 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1277 g_return_if_fail (GST_IS_PAD (pad));
1279 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1280 GST_CAT_DEBUG (GST_CAT_PADS, "setcapsfunc for %s:%s set to %s",
1281 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (setcaps));
1285 * gst_pad_set_bufferalloc_function:
1286 * @pad: a sink #GstPad.
1287 * @bufalloc: the #GstPadBufferAllocFunction to set.
1289 * Sets the given bufferalloc function for the pad. Note that the
1290 * bufferalloc function can only be set on sinkpads.
1293 gst_pad_set_bufferalloc_function (GstPad * pad,
1294 GstPadBufferAllocFunction bufalloc)
1296 g_return_if_fail (GST_IS_PAD (pad));
1297 g_return_if_fail (GST_PAD_IS_SINK (pad));
1299 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1300 GST_CAT_DEBUG (GST_CAT_PADS, "bufferallocfunc for %s:%s set to %s",
1301 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (bufalloc));
1306 * @srcpad: the source #GstPad to unlink.
1307 * @sinkpad: the sink #GstPad to unlink.
1309 * Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
1312 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1313 * the pads were not linked together.
1318 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1320 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1321 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1323 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1324 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1325 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1329 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1334 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1337 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1338 goto not_linked_together;
1340 if (GST_PAD_UNLINKFUNC (srcpad)) {
1341 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1343 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1344 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1347 /* first clear peers */
1348 GST_PAD_PEER (srcpad) = NULL;
1349 GST_PAD_PEER (sinkpad) = NULL;
1351 GST_UNLOCK (sinkpad);
1352 GST_UNLOCK (srcpad);
1354 /* fire off a signal to each of the pads telling them
1355 * that they've been unlinked */
1356 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1357 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1359 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1360 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1366 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1367 GST_UNLOCK (srcpad);
1372 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1373 GST_UNLOCK (sinkpad);
1374 GST_UNLOCK (srcpad);
1377 not_linked_together:
1379 /* we do not emit a warning in this case because unlinking cannot
1380 * be made MT safe.*/
1381 GST_UNLOCK (sinkpad);
1382 GST_UNLOCK (srcpad);
1388 * gst_pad_is_linked:
1389 * @pad: pad to check
1391 * Checks if a @pad is linked to another pad or not.
1393 * Returns: TRUE if the pad is linked, FALSE otherwise.
1398 gst_pad_is_linked (GstPad * pad)
1402 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1405 result = (GST_PAD_PEER (pad) != NULL);
1411 /* get the caps from both pads and see if the intersection
1414 * This function should be called with the pad LOCK on both
1418 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1423 srccaps = gst_pad_get_caps_unlocked (src);
1424 sinkcaps = gst_pad_get_caps_unlocked (sink);
1425 GST_CAT_DEBUG (GST_CAT_CAPS, " src caps %" GST_PTR_FORMAT, srccaps);
1426 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1428 /* if we have caps on both pads we can check the intersection */
1429 if (srccaps && sinkcaps) {
1432 icaps = gst_caps_intersect (srccaps, sinkcaps);
1433 gst_caps_unref (srccaps);
1434 gst_caps_unref (sinkcaps);
1436 GST_CAT_DEBUG (GST_CAT_CAPS,
1437 "intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
1439 if (!icaps || gst_caps_is_empty (icaps)) {
1440 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is empty");
1441 gst_caps_unref (icaps);
1444 gst_caps_unref (icaps);
1450 /* check if the grandparents of both pads are the same.
1451 * This check is required so that we don't try to link
1452 * pads from elements in different bins without ghostpads.
1454 * The LOCK should be helt on both pads
1457 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1459 GstObject *psrc, *psink;
1460 gboolean res = TRUE;
1462 psrc = GST_OBJECT_PARENT (src);
1463 psink = GST_OBJECT_PARENT (sink);
1465 /* if one of the pads has no parent, we allow the link */
1466 if (psrc && psink) {
1467 /* if the parents are the same, we have a loop */
1468 if (psrc == psink) {
1469 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1474 /* if they both have a parent, we check the grandparents */
1475 psrc = gst_object_get_parent (psrc);
1476 psink = gst_object_get_parent (psink);
1478 if (psrc != psink) {
1479 /* if they have grandparents but they are not the same */
1480 GST_CAT_DEBUG (GST_CAT_CAPS,
1481 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1482 GST_PTR_FORMAT, psrc, psink);
1486 gst_object_unref (psrc);
1488 gst_object_unref (psink);
1494 /* FIXME leftover from an attempt at refactoring... */
1495 /* call with the two pads unlocked */
1496 static GstPadLinkReturn
1497 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1499 /* generic checks */
1500 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
1501 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
1503 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1504 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1508 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1511 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1512 goto src_was_linked;
1516 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1519 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1520 goto sink_was_linked;
1522 /* check hierarchy, pads can only be linked if the grandparents
1524 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1525 goto wrong_hierarchy;
1527 /* check pad caps for non-empty intersection */
1528 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1531 /* FIXME check pad scheduling for non-empty intersection */
1533 return GST_PAD_LINK_OK;
1537 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1538 GST_UNLOCK (srcpad);
1539 return GST_PAD_LINK_WRONG_DIRECTION;
1543 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was linked",
1544 GST_DEBUG_PAD_NAME (srcpad));
1545 /* we do not emit a warning in this case because unlinking cannot
1546 * be made MT safe.*/
1547 GST_UNLOCK (srcpad);
1548 return GST_PAD_LINK_WAS_LINKED;
1552 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1553 GST_UNLOCK (sinkpad);
1554 GST_UNLOCK (srcpad);
1555 return GST_PAD_LINK_WRONG_DIRECTION;
1559 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was linked",
1560 GST_DEBUG_PAD_NAME (sinkpad));
1561 /* we do not emit a warning in this case because unlinking cannot
1562 * be made MT safe.*/
1563 GST_UNLOCK (sinkpad);
1564 GST_UNLOCK (srcpad);
1565 return GST_PAD_LINK_WAS_LINKED;
1569 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1570 GST_UNLOCK (sinkpad);
1571 GST_UNLOCK (srcpad);
1572 return GST_PAD_LINK_WRONG_HIERARCHY;
1576 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1577 GST_UNLOCK (sinkpad);
1578 GST_UNLOCK (srcpad);
1579 return GST_PAD_LINK_NOFORMAT;
1585 * @srcpad: the source #GstPad to link.
1586 * @sinkpad: the sink #GstPad to link.
1588 * Links the source pad and the sink pad.
1590 * Returns: A result code indicating if the connection worked or
1596 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1598 GstPadLinkReturn result;
1600 /* prepare will also lock the two pads */
1601 result = gst_pad_link_prepare (srcpad, sinkpad);
1603 if (result != GST_PAD_LINK_OK)
1604 goto prepare_failed;
1606 GST_UNLOCK (sinkpad);
1607 GST_UNLOCK (srcpad);
1609 /* FIXME released the locks here, concurrent thread might link
1610 * something else. */
1611 if (GST_PAD_LINKFUNC (srcpad)) {
1612 /* this one will call the peer link function */
1613 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
1614 } else if (GST_PAD_LINKFUNC (sinkpad)) {
1615 /* if no source link function, we need to call the sink link
1616 * function ourselves. */
1617 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
1619 result = GST_PAD_LINK_OK;
1625 if (result == GST_PAD_LINK_OK) {
1626 GST_PAD_PEER (srcpad) = sinkpad;
1627 GST_PAD_PEER (sinkpad) = srcpad;
1629 GST_UNLOCK (sinkpad);
1630 GST_UNLOCK (srcpad);
1632 /* fire off a signal to each of the pads telling them
1633 * that they've been linked */
1634 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
1635 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
1637 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
1638 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1640 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
1641 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1643 GST_UNLOCK (sinkpad);
1644 GST_UNLOCK (srcpad);
1655 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
1657 /* this function would need checks if it weren't static */
1660 gst_object_replace ((GstObject **) & pad->padtemplate, (GstObject *) templ);
1664 gst_pad_template_pad_created (templ, pad);
1668 * gst_pad_get_pad_template:
1671 * Gets the template for @pad.
1673 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
1674 * if this pad has no template.
1676 * FIXME: currently returns an unrefcounted padtemplate.
1679 gst_pad_get_pad_template (GstPad * pad)
1681 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1683 return GST_PAD_PAD_TEMPLATE (pad);
1687 /* should be called with the pad LOCK held */
1688 /* refs the caps, so caller is responsible for getting it unreffed */
1690 gst_pad_get_caps_unlocked (GstPad * pad)
1692 GstCaps *result = NULL;
1694 GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
1695 GST_DEBUG_PAD_NAME (pad), pad);
1697 if (GST_PAD_GETCAPSFUNC (pad)) {
1698 GST_CAT_DEBUG (GST_CAT_CAPS, "dispatching to pad getcaps function");
1700 GST_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
1702 result = GST_PAD_GETCAPSFUNC (pad) (pad);
1704 GST_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
1706 if (result == NULL) {
1707 g_critical ("pad %s:%s returned NULL caps from getcaps function",
1708 GST_DEBUG_PAD_NAME (pad));
1710 GST_CAT_DEBUG (GST_CAT_CAPS,
1711 "pad getcaps %s:%s returned %" GST_PTR_FORMAT,
1712 GST_DEBUG_PAD_NAME (pad), result);
1713 #ifndef G_DISABLE_ASSERT
1714 /* check that the returned caps are a real subset of the template caps */
1715 if (GST_PAD_PAD_TEMPLATE (pad)) {
1716 const GstCaps *templ_caps =
1717 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
1718 if (!gst_caps_is_subset (result, templ_caps)) {
1721 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
1722 "pad returned caps %" GST_PTR_FORMAT
1723 " which are not a real subset of its template caps %"
1724 GST_PTR_FORMAT, result, templ_caps);
1726 ("pad %s:%s returned caps that are not a real subset of its template caps",
1727 GST_DEBUG_PAD_NAME (pad));
1728 temp = gst_caps_intersect (templ_caps, result);
1729 gst_caps_unref (result);
1737 if (GST_PAD_PAD_TEMPLATE (pad)) {
1738 GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
1740 result = GST_PAD_TEMPLATE_CAPS (templ);
1741 GST_CAT_DEBUG (GST_CAT_CAPS,
1742 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
1745 result = gst_caps_ref (result);
1748 if (GST_PAD_CAPS (pad)) {
1749 result = GST_PAD_CAPS (pad);
1751 GST_CAT_DEBUG (GST_CAT_CAPS,
1752 "using pad caps %p %" GST_PTR_FORMAT, result, result);
1754 result = gst_caps_ref (result);
1758 GST_CAT_DEBUG (GST_CAT_CAPS, "pad has no caps");
1759 result = gst_caps_new_empty ();
1767 * @pad: a #GstPad to get the capabilities of.
1769 * Gets the capabilities this pad can produce or consume.
1770 * Note that this method doesn't necessarily returns the caps set by
1771 * #gst_pad_set_caps - use #GST_PAD_CAPS for that instead.
1772 * gst_pad_get_caps returns all possible caps a pad can operate with, using
1773 * the pad's get_caps function;
1774 * this returns the pad template caps if not explicitly set.
1776 * Returns: a newly allocated copy of the #GstCaps of this pad.
1781 gst_pad_get_caps (GstPad * pad)
1783 GstCaps *result = NULL;
1785 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1789 GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
1790 GST_DEBUG_PAD_NAME (pad), pad);
1792 if (G_UNLIKELY (GST_PAD_IS_IN_GETCAPS (pad)))
1793 goto was_dispatching;
1795 result = gst_pad_get_caps_unlocked (pad);
1802 GST_CAT_DEBUG (GST_CAT_CAPS,
1803 "pad %s:%s is already dispatching!", GST_DEBUG_PAD_NAME (pad));
1804 g_warning ("pad %s:%s recursively called getcaps!",
1805 GST_DEBUG_PAD_NAME (pad));
1812 * gst_pad_peer_get_caps:
1813 * @pad: a #GstPad to get the peer capabilities of.
1815 * Gets the capabilities of the peer connected to this pad.
1817 * Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
1818 * gst_caps_unref to get rid of it. this function returns NULL if there is no
1819 * peer pad or when this function is called recursively from a getcaps function.
1822 gst_pad_peer_get_caps (GstPad * pad)
1825 GstCaps *result = NULL;
1827 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1831 GST_CAT_DEBUG (GST_CAT_CAPS, "get peer caps of %s:%s (%p)",
1832 GST_DEBUG_PAD_NAME (pad), pad);
1834 peerpad = GST_PAD_PEER (pad);
1835 if (G_UNLIKELY (peerpad == NULL))
1838 if (G_UNLIKELY (GST_PAD_IS_IN_GETCAPS (peerpad)))
1839 goto was_dispatching;
1841 gst_object_ref (peerpad);
1844 result = gst_pad_get_caps (peerpad);
1846 gst_object_unref (peerpad);
1857 GST_CAT_DEBUG (GST_CAT_CAPS,
1858 "pad %s:%s is already dispatching!", GST_DEBUG_PAD_NAME (pad));
1859 g_warning ("pad %s:%s recursively called getcaps!",
1860 GST_DEBUG_PAD_NAME (pad));
1867 fixate_value (GValue * dest, const GValue * src)
1869 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
1870 g_value_init (dest, G_TYPE_INT);
1871 g_value_set_int (dest, gst_value_get_int_range_min (src));
1872 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
1873 g_value_init (dest, G_TYPE_DOUBLE);
1874 g_value_set_double (dest, gst_value_get_double_range_min (src));
1875 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
1876 GValue temp = { 0 };
1878 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
1879 if (!fixate_value (dest, &temp))
1880 gst_value_init_and_copy (dest, &temp);
1881 g_value_unset (&temp);
1882 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
1883 gboolean res = FALSE;
1886 g_value_init (dest, GST_TYPE_ARRAY);
1887 for (n = 0; n < gst_value_list_get_size (src); n++) {
1889 const GValue *orig_kid = gst_value_list_get_value (src, n);
1891 if (!fixate_value (&kid, orig_kid))
1892 gst_value_init_and_copy (&kid, orig_kid);
1895 gst_value_list_append_value (dest, &kid);
1896 g_value_unset (&kid);
1900 g_value_unset (dest);
1911 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
1913 GstStructure *s = data;
1916 if (fixate_value (&v, value)) {
1917 gst_structure_id_set_value (s, field_id, &v);
1925 * gst_pad_fixate_caps:
1926 * @pad: a #GstPad to fixate
1927 * @caps: the #GstCaps to fixate
1929 * Fixate a caps on the given pad. Modifies the caps in place, so you should
1930 * make sure that the caps are actually writable (see gst_caps_make_writable()).
1933 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
1935 GstPadFixateCapsFunction fixatefunc;
1938 g_return_if_fail (GST_IS_PAD (pad));
1939 g_return_if_fail (caps != NULL);
1941 if (gst_caps_is_fixed (caps))
1944 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
1946 fixatefunc (pad, caps);
1949 /* default fixation */
1950 for (n = 0; n < gst_caps_get_size (caps); n++) {
1951 GstStructure *s = gst_caps_get_structure (caps, n);
1953 gst_structure_foreach (s, gst_pad_default_fixate, s);
1958 * gst_pad_accept_caps:
1959 * @pad: a #GstPad to check
1960 * @caps: a #GstCaps to check on the pad
1962 * Check if the given pad accepts the caps.
1964 * Returns: TRUE if the pad can accept the caps.
1967 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
1970 GstPadAcceptCapsFunction acceptfunc;
1972 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1974 /* any pad can be unnegotiated */
1979 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
1981 GST_CAT_DEBUG (GST_CAT_CAPS, "pad accept caps of %s:%s (%p)",
1982 GST_DEBUG_PAD_NAME (pad), pad);
1986 /* we can call the function */
1987 result = acceptfunc (pad, caps);
1989 /* else see get the caps and see if it intersects to something
1994 allowed = gst_pad_get_caps (pad);
1996 intersect = gst_caps_intersect (allowed, caps);
1998 result = !gst_caps_is_empty (intersect);
2000 gst_caps_unref (allowed);
2001 gst_caps_unref (intersect);
2010 * gst_pad_peer_accept_caps:
2011 * @pad: a #GstPad to check
2012 * @caps: a #GstCaps to check on the pad
2014 * Check if the given pad accepts the caps.
2016 * Returns: TRUE if the pad can accept the caps.
2019 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2024 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2028 GST_CAT_DEBUG (GST_CAT_CAPS, "peer accept caps of %s:%s (%p)",
2029 GST_DEBUG_PAD_NAME (pad), pad);
2031 peerpad = GST_PAD_PEER (pad);
2032 if (G_UNLIKELY (peerpad == NULL))
2035 result = gst_pad_accept_caps (peerpad, caps);
2049 * @pad: a #GstPad to set the capabilities of.
2050 * @caps: a #GstCaps to set.
2052 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2053 * caps on the pad will be unreffed. This function refs the caps so you should
2054 * unref if as soon as you don't need it anymore.
2055 * It is possible to set NULL caps, which will make the pad unnegotiated
2058 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2059 * or bad parameters were provided to this function.
2064 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2066 GstPadSetCapsFunction setcaps;
2069 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2070 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2073 setcaps = GST_PAD_SETCAPSFUNC (pad);
2075 existing = GST_PAD_CAPS (pad);
2076 if (caps == existing)
2077 goto setting_same_caps;
2078 else if (caps && existing && gst_caps_is_equal (caps, existing))
2079 goto setting_same_caps;
2081 /* call setcaps function to configure the pad */
2082 if (setcaps != NULL && caps) {
2083 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2084 GST_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2086 if (!setcaps (pad, caps))
2089 GST_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2091 GST_CAT_DEBUG (GST_CAT_CAPS, "pad %s:%s was dispatching",
2092 GST_DEBUG_PAD_NAME (pad));
2096 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2097 GST_CAT_DEBUG (GST_CAT_CAPS, "%s:%s caps %" GST_PTR_FORMAT,
2098 GST_DEBUG_PAD_NAME (pad), caps);
2101 g_object_notify (G_OBJECT (pad), "caps");
2108 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2109 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2110 "caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
2117 GST_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2118 GST_CAT_DEBUG (GST_CAT_CAPS,
2119 "pad %s:%s, caps %" GST_PTR_FORMAT " could not be set",
2120 GST_DEBUG_PAD_NAME (pad), caps);
2128 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2130 GstPadAcceptCapsFunction acceptcaps;
2131 GstPadSetCapsFunction setcaps;
2134 acceptcaps = GST_PAD_ACCEPTCAPSFUNC (pad);
2135 setcaps = GST_PAD_SETCAPSFUNC (pad);
2137 /* See if pad accepts the caps, by calling acceptcaps, only
2138 * needed if no setcaps function */
2139 if (setcaps == NULL && acceptcaps != NULL) {
2140 if (!acceptcaps (pad, caps))
2143 /* set caps on pad if call succeeds */
2144 res = gst_pad_set_caps (pad, caps);
2145 /* no need to unref the caps here, set_caps takes a ref and
2146 * our ref goes away when we leave this function. */
2152 GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
2157 /* returns TRUE if the src pad could be configured to accept the given caps */
2159 gst_pad_configure_src (GstPad * pad, GstCaps * caps)
2161 GstPadAcceptCapsFunction acceptcaps;
2162 GstPadSetCapsFunction setcaps;
2165 acceptcaps = GST_PAD_ACCEPTCAPSFUNC (pad);
2166 setcaps = GST_PAD_SETCAPSFUNC (pad);
2168 /* See if pad accepts the caps, by calling acceptcaps, only
2169 * needed if no setcaps function */
2170 if (setcaps == NULL && acceptcaps != NULL) {
2171 if (!acceptcaps (pad, caps))
2174 /* set caps on pad if call succeeds */
2175 res = gst_pad_set_caps (pad, caps);
2176 /* no need to unref the caps here, set_caps takes a ref and
2177 * our ref goes away when we leave this function. */
2183 GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
2189 * gst_pad_get_pad_template_caps:
2190 * @pad: a #GstPad to get the template capabilities from.
2192 * Gets the capabilities for @pad's template.
2194 * Returns: the #GstCaps of this pad template. If you intend to keep a reference
2195 * on the caps, make a copy (see gst_caps_copy ()).
2198 gst_pad_get_pad_template_caps (GstPad * pad)
2200 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2202 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2204 if (GST_PAD_PAD_TEMPLATE (pad))
2205 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2207 return gst_static_caps_get (&anycaps);
2213 * @pad: a #GstPad to get the peer of.
2215 * Gets the peer of @pad. This function refs the peer pad so
2216 * you need to unref it after use.
2218 * Returns: the peer #GstPad. Unref after usage.
2223 gst_pad_get_peer (GstPad * pad)
2227 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2230 result = GST_PAD_PEER (pad);
2232 gst_object_ref (result);
2239 * gst_pad_get_allowed_caps:
2240 * @srcpad: a #GstPad, it must a a source pad.
2242 * Gets the capabilities of the allowed media types that can flow through
2243 * @srcpad and its peer. The pad must be a source pad.
2244 * The caller must free the resulting caps.
2246 * Returns: the allowed #GstCaps of the pad link. Free the caps when
2247 * you no longer need it. This function returns NULL when the @srcpad has no
2253 gst_pad_get_allowed_caps (GstPad * srcpad)
2260 g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
2261 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
2265 peer = GST_PAD_PEER (srcpad);
2266 if (G_UNLIKELY (peer == NULL))
2269 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting allowed caps",
2270 GST_DEBUG_PAD_NAME (srcpad));
2272 gst_object_ref (peer);
2273 GST_UNLOCK (srcpad);
2274 mycaps = gst_pad_get_caps (srcpad);
2276 peercaps = gst_pad_get_caps (peer);
2277 gst_object_unref (peer);
2279 caps = gst_caps_intersect (mycaps, peercaps);
2280 gst_caps_unref (peercaps);
2281 gst_caps_unref (mycaps);
2283 GST_CAT_DEBUG (GST_CAT_CAPS, "allowed caps %" GST_PTR_FORMAT, caps);
2289 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
2290 GST_DEBUG_PAD_NAME (srcpad));
2291 GST_UNLOCK (srcpad);
2298 * gst_pad_get_negotiated_caps:
2301 * Gets the capabilities of the media type that currently flows through @pad
2304 * This function can be used on both src and sinkpads. Note that srcpads are
2305 * always negotiated before sinkpads so it is possible that the negotiated caps
2306 * on the srcpad do not match the negotiated caps of the peer.
2308 * Returns: the negotiated #GstCaps of the pad link. Free the caps when
2309 * you no longer need it. This function returns NULL when the @pad has no
2310 * peer or is not negotiated yet.
2315 gst_pad_get_negotiated_caps (GstPad * pad)
2320 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2324 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2327 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting negotiated caps",
2328 GST_DEBUG_PAD_NAME (pad));
2330 caps = GST_PAD_CAPS (pad);
2332 gst_caps_ref (caps);
2335 GST_CAT_DEBUG (GST_CAT_CAPS, "negotiated caps %" GST_PTR_FORMAT, caps);
2341 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
2342 GST_DEBUG_PAD_NAME (pad));
2350 * gst_pad_alloc_buffer:
2351 * @pad: a source #GstPad
2352 * @offset: the offset of the new buffer in the stream
2353 * @size: the size of the new buffer
2354 * @caps: the caps of the new buffer
2355 * @buf: a newly allocated buffer
2357 * Allocates a new, empty buffer optimized to push to pad @pad. This
2358 * function only works if @pad is a source pad and has a peer.
2360 * You need to check the caps of the buffer after performing this
2361 * function and renegotiate to the format if needed.
2363 * A new, empty #GstBuffer will be put in the @buf argument.
2365 * Returns: a result code indicating success of the operation. Any
2366 * result code other than GST_FLOW_OK is an error and @buf should
2368 * An error can occur if the pad is not connected or when the downstream
2369 * peer elements cannot provide an acceptable buffer.
2374 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
2379 GstPadBufferAllocFunction bufferallocfunc;
2380 gboolean caps_changed;
2382 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2383 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2384 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2387 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2388 handle_pad_block (pad);
2390 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2393 gst_object_ref (peer);
2396 if (G_LIKELY ((bufferallocfunc = peer->bufferallocfunc) == NULL))
2400 /* when the peer is flushing we cannot give a buffer */
2401 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (peer)))
2404 if (offset == GST_BUFFER_OFFSET_NONE) {
2405 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2406 "calling bufferallocfunc &%s (@%p) of peer pad %s:%s for size %d offset NONE",
2407 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2408 &bufferallocfunc, GST_DEBUG_PAD_NAME (peer), size);
2410 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2411 "calling bufferallocfunc &%s (@%p) of peer pad %s:%s for size %d offset %"
2412 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2413 &bufferallocfunc, GST_DEBUG_PAD_NAME (peer), size, offset);
2417 ret = bufferallocfunc (peer, offset, size, caps, buf);
2419 if (G_UNLIKELY (ret != GST_FLOW_OK))
2421 if (G_UNLIKELY (*buf == NULL))
2424 /* If the buffer alloc function didn't set up the caps like it should,
2426 if (caps && (GST_BUFFER_CAPS (*buf) == NULL)) {
2427 GST_WARNING ("Buffer allocation function for pad % " GST_PTR_FORMAT
2428 " did not set up caps. Setting", peer);
2430 gst_buffer_set_caps (*buf, caps);
2434 gst_object_unref (peer);
2436 /* FIXME, move capnego this into a base class? */
2437 caps = GST_BUFFER_CAPS (*buf);
2438 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2439 /* we got a new datatype on the pad, see if it can handle it */
2440 if (G_UNLIKELY (caps_changed)) {
2441 GST_DEBUG ("caps changed to %" GST_PTR_FORMAT, caps);
2442 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps)))
2443 goto not_negotiated;
2449 /* pad has no peer */
2450 GST_CAT_DEBUG (GST_CAT_PADS,
2451 "%s:%s called bufferallocfunc but had no peer",
2452 GST_DEBUG_PAD_NAME (pad));
2454 return GST_FLOW_NOT_LINKED;
2458 /* peer was flushing */
2460 gst_object_unref (peer);
2461 GST_CAT_DEBUG (GST_CAT_PADS,
2462 "%s:%s called bufferallocfunc but peer was flushing",
2463 GST_DEBUG_PAD_NAME (pad));
2464 return GST_FLOW_WRONG_STATE;
2466 /* fallback case, allocate a buffer of our own, add pad caps. */
2469 GST_CAT_DEBUG (GST_CAT_PADS,
2470 "%s:%s fallback buffer alloc", GST_DEBUG_PAD_NAME (pad));
2471 *buf = gst_buffer_new_and_alloc (size);
2472 GST_BUFFER_OFFSET (*buf) = offset;
2473 gst_buffer_set_caps (*buf, caps);
2481 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2482 "alloc function retured unacceptable buffer");
2483 return GST_FLOW_NOT_NEGOTIATED;
2487 gst_object_unref (peer);
2488 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2489 "alloc function retured error %s", gst_flow_get_name (ret));
2495 * gst_pad_get_internal_links_default:
2496 * @pad: the #GstPad to get the internal links of.
2498 * Gets a list of pads to which the given pad is linked to
2499 * inside of the parent element.
2500 * This is the default handler, and thus returns a list of all of the
2501 * pads inside the parent element with opposite direction.
2502 * The caller must free this list after use.
2504 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
2509 gst_pad_get_internal_links_default (GstPad * pad)
2514 GstPadDirection direction;
2516 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2518 direction = pad->direction;
2520 parent = GST_PAD_PARENT (pad);
2524 parent_pads = parent->pads;
2526 while (parent_pads) {
2527 GstPad *parent_pad = GST_PAD_CAST (parent_pads->data);
2529 if (parent_pad->direction != direction) {
2530 res = g_list_prepend (res, parent_pad);
2533 parent_pads = g_list_next (parent_pads);
2540 * gst_pad_get_internal_links:
2541 * @pad: the #GstPad to get the internal links of.
2543 * Gets a list of pads to which the given pad is linked to
2544 * inside of the parent element.
2545 * The caller must free this list after use.
2547 * Returns: a newly allocated #GList of pads.
2552 gst_pad_get_internal_links (GstPad * pad)
2556 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2558 if (GST_PAD_INTLINKFUNC (pad))
2559 res = GST_PAD_INTLINKFUNC (pad) (pad);
2566 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
2571 GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
2574 result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
2576 orig = pads = gst_pad_get_internal_links (pad);
2579 GstPad *eventpad = GST_PAD_CAST (pads->data);
2581 pads = g_list_next (pads);
2583 /* for all of the internally-linked pads that are actually linked */
2584 if (GST_PAD_IS_LINKED (eventpad)) {
2585 if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
2586 /* for each pad we send to, we should ref the event; it's up
2587 * to downstream to unref again when handled. */
2588 GST_LOG_OBJECT (pad, "Reffing and sending event %p to %s:%s", event,
2589 GST_DEBUG_PAD_NAME (eventpad));
2590 gst_event_ref (event);
2591 gst_pad_push_event (eventpad, event);
2593 /* we only send the event on one pad, multi-sinkpad elements
2594 * should implement a handler */
2595 GST_LOG_OBJECT (pad, "sending event %p to one sink pad %s:%s", event,
2596 GST_DEBUG_PAD_NAME (eventpad));
2597 result = gst_pad_push_event (eventpad, event);
2602 /* we handled the incoming event so we unref once */
2603 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
2604 gst_event_unref (event);
2613 * gst_pad_event_default:
2614 * @pad: a #GstPad to call the default event handler on.
2615 * @event: the #GstEvent to handle.
2617 * Invokes the default event handler for the given pad. End-of-stream and
2618 * discontinuity events are handled specially, and then the event is sent to all
2619 * pads internally linked to @pad. Note that if there are many possible sink
2620 * pads that are internally linked to @pad, only one will be sent an event.
2621 * Multi-sinkpad elements should implement custom event handlers.
2623 * Returns: TRUE if the event was sent succesfully.
2626 gst_pad_event_default (GstPad * pad, GstEvent * event)
2628 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2629 g_return_val_if_fail (event != NULL, FALSE);
2631 switch (GST_EVENT_TYPE (event)) {
2634 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
2635 gst_pad_pause_task (pad);
2641 return gst_pad_event_default_dispatch (pad, event);
2645 * gst_pad_dispatcher:
2646 * @pad: a #GstPad to dispatch.
2647 * @dispatch: the #GstDispatcherFunction to call.
2648 * @data: gpointer user data passed to the dispatcher function.
2650 * Invokes the given dispatcher function on all pads that are
2651 * internally linked to the given pad.
2652 * The GstPadDispatcherFunction should return TRUE when no further pads
2653 * need to be processed.
2655 * Returns: TRUE if one of the dispatcher functions returned TRUE.
2658 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
2661 gboolean res = FALSE;
2662 GList *int_pads, *orig;
2664 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2665 g_return_val_if_fail (dispatch != NULL, FALSE);
2667 orig = int_pads = gst_pad_get_internal_links (pad);
2670 GstPad *int_pad = GST_PAD_CAST (int_pads->data);
2671 GstPad *int_peer = GST_PAD_PEER (int_pad);
2674 res = dispatch (int_peer, data);
2678 int_pads = g_list_next (int_pads);
2688 * @pad: a #GstPad to invoke the default query on.
2689 * @query: the #GstQuery to perform.
2691 * Dispatches a query to a pad. The query should have been allocated by the
2692 * caller via one of the type-specific allocation functions in gstquery.h. The
2693 * element is responsible for filling the query with an appropriate response,
2694 * which should then be parsed with a type-specific query parsing function.
2696 * Again, the caller is responsible for both the allocation and deallocation of
2697 * the query structure.
2699 * Returns: TRUE if the query could be performed.
2702 gst_pad_query (GstPad * pad, GstQuery * query)
2704 GstPadQueryFunction func;
2706 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2707 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2709 GST_DEBUG ("sending query %p to pad %s:%s", query, GST_DEBUG_PAD_NAME (pad));
2711 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
2714 return func (pad, query);
2718 GST_DEBUG ("pad had no query function");
2724 gst_pad_query_default (GstPad * pad, GstQuery * query)
2726 switch (GST_QUERY_TYPE (query)) {
2727 case GST_QUERY_POSITION:
2728 case GST_QUERY_SEEKING:
2729 case GST_QUERY_FORMATS:
2730 case GST_QUERY_LATENCY:
2731 case GST_QUERY_JITTER:
2732 case GST_QUERY_RATE:
2733 case GST_QUERY_CONVERT:
2735 return gst_pad_dispatcher
2736 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
2740 #ifndef GST_DISABLE_LOADSAVE
2741 /* FIXME: why isn't this on a GstElement ? */
2743 * gst_pad_load_and_link:
2744 * @self: an #xmlNodePtr to read the description from.
2745 * @parent: the #GstObject element that owns the pad.
2747 * Reads the pad definition from the XML node and links the given pad
2748 * in the element to a pad of an element up in the hierarchy.
2751 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
2753 xmlNodePtr field = self->xmlChildrenNode;
2754 GstPad *pad = NULL, *targetpad;
2758 GstObject *grandparent;
2762 if (!strcmp ((char *) field->name, "name")) {
2763 name = (gchar *) xmlNodeGetContent (field);
2764 pad = gst_element_get_pad (GST_ELEMENT (parent), name);
2766 } else if (!strcmp ((char *) field->name, "peer")) {
2767 peer = (gchar *) xmlNodeGetContent (field);
2769 field = field->next;
2771 g_return_if_fail (pad != NULL);
2776 split = g_strsplit (peer, ".", 2);
2778 if (split[0] == NULL || split[1] == NULL) {
2779 GST_CAT_DEBUG (GST_CAT_XML,
2780 "Could not parse peer '%s' for pad %s:%s, leaving unlinked",
2781 peer, GST_DEBUG_PAD_NAME (pad));
2788 g_return_if_fail (split[0] != NULL);
2789 g_return_if_fail (split[1] != NULL);
2791 grandparent = gst_object_get_parent (parent);
2793 if (grandparent && GST_IS_BIN (grandparent)) {
2794 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
2801 targetpad = gst_element_get_pad (target, split[1]);
2803 if (targetpad == NULL)
2806 gst_pad_link (pad, targetpad);
2813 * gst_pad_save_thyself:
2814 * @pad: a #GstPad to save.
2815 * @parent: the parent #xmlNodePtr to save the description in.
2817 * Saves the pad into an xml representation.
2819 * Returns: the #xmlNodePtr representation of the pad.
2822 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
2827 g_return_val_if_fail (GST_IS_PAD (object), NULL);
2829 pad = GST_PAD (object);
2831 xmlNewChild (parent, NULL, (xmlChar *) "name",
2832 (xmlChar *) GST_PAD_NAME (pad));
2833 if (GST_PAD_PEER (pad) != NULL) {
2836 peer = GST_PAD_PEER (pad);
2837 /* first check to see if the peer's parent's parent is the same */
2838 /* we just save it off */
2839 content = g_strdup_printf ("%s.%s",
2840 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
2841 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
2844 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
2851 * gst_ghost_pad_save_thyself:
2852 * @pad: a ghost #GstPad to save.
2853 * @parent: the parent #xmlNodePtr to save the description in.
2855 * Saves the ghost pad into an xml representation.
2857 * Returns: the #xmlNodePtr representation of the pad.
2860 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
2864 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
2866 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
2867 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
2868 xmlNewChild (self, NULL, (xmlChar *) "parent",
2869 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
2871 /* FIXME FIXME FIXME! */
2876 #endif /* GST_DISABLE_LOADSAVE */
2879 * should be called with pad lock held
2884 handle_pad_block (GstPad * pad)
2886 GstPadBlockCallback callback;
2889 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2890 "signal block taken on pad %s:%s", GST_DEBUG_PAD_NAME (pad));
2892 /* need to grab extra ref for the callbacks */
2893 gst_object_ref (pad);
2895 callback = pad->block_callback;
2897 user_data = pad->block_data;
2899 callback (pad, TRUE, user_data);
2902 GST_PAD_BLOCK_SIGNAL (pad);
2905 while (GST_PAD_IS_BLOCKED (pad))
2906 GST_PAD_BLOCK_WAIT (pad);
2908 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
2910 callback = pad->block_callback;
2912 user_data = pad->block_data;
2914 callback (pad, FALSE, user_data);
2917 GST_PAD_BLOCK_SIGNAL (pad);
2920 gst_object_unref (pad);
2923 /**********************************************************************
2924 * Data passing functions
2928 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
2931 GValue args[2] = { {0}, {0} };
2936 g_value_init (&ret, G_TYPE_BOOLEAN);
2937 g_value_set_boolean (&ret, TRUE);
2938 g_value_init (&args[0], GST_TYPE_PAD);
2939 g_value_set_object (&args[0], pad);
2940 g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
2941 gst_value_set_mini_object (&args[1], obj);
2943 if (GST_IS_EVENT (obj))
2944 detail = event_quark;
2946 detail = buffer_quark;
2949 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
2950 res = g_value_get_boolean (&ret);
2953 g_value_unset (&ret);
2954 g_value_unset (&args[0]);
2955 g_value_unset (&args[1]);
2962 * @pad: a sink #GstPad.
2963 * @buffer: the #GstBuffer to send.
2965 * Chain a buffer to @pad.
2967 * Returns: a #GstFlowReturn from the pad.
2972 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
2975 gboolean caps_changed;
2976 GstPadChainFunction chainfunc;
2978 gboolean emit_signal;
2980 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2981 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
2983 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
2984 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
2986 GST_STREAM_LOCK (pad);
2989 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2992 caps = GST_BUFFER_CAPS (buffer);
2993 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2995 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
2998 /* see if the signal should be emited, we emit before caps nego as
2999 * we might drop the buffer and do capsnego for nothing. */
3000 if (G_UNLIKELY (emit_signal)) {
3001 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3005 /* we got a new datatype on the pad, see if it can handle it */
3006 if (G_UNLIKELY (caps_changed)) {
3007 GST_DEBUG ("caps changed to %" GST_PTR_FORMAT, caps);
3008 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
3009 goto not_negotiated;
3012 /* NOTE: we read the chainfunc unlocked.
3013 * we cannot hold the lock for the pad so we might send
3014 * the data to the wrong function. This is not really a
3015 * problem since functions are assigned at creation time
3016 * and don't change that often... */
3017 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
3020 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3021 "calling chainfunction &%s of pad %s:%s",
3022 GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_DEBUG_PAD_NAME (pad));
3024 ret = chainfunc (pad, buffer);
3026 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3027 "called chainfunction &%s of pad %s:%s, returned %s",
3028 GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_DEBUG_PAD_NAME (pad),
3029 gst_flow_get_name (ret));
3031 GST_STREAM_UNLOCK (pad);
3038 gst_buffer_unref (buffer);
3039 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3040 "pushing, but pad was flushing");
3042 GST_STREAM_UNLOCK (pad);
3043 return GST_FLOW_WRONG_STATE;
3047 gst_buffer_unref (buffer);
3048 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3049 GST_STREAM_UNLOCK (pad);
3054 gst_buffer_unref (buffer);
3055 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3056 "pushing buffer but pad did not accept");
3057 GST_STREAM_UNLOCK (pad);
3058 return GST_FLOW_NOT_NEGOTIATED;
3062 gst_buffer_unref (buffer);
3063 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3064 "pushing, but not chainhandler");
3065 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3066 ("push on pad %s:%s but it has no chainfunction",
3067 GST_DEBUG_PAD_NAME (pad)));
3068 GST_STREAM_UNLOCK (pad);
3069 return GST_FLOW_ERROR;
3075 * @pad: a source #GstPad.
3076 * @buffer: the #GstBuffer to push.
3078 * Pushes a buffer to the peer of @pad. @pad must be linked.
3080 * Returns: a #GstFlowReturn from the peer pad.
3085 gst_pad_push (GstPad * pad, GstBuffer * buffer)
3089 gboolean emit_signal;
3091 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3092 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3093 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3094 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3097 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3098 handle_pad_block (pad);
3100 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3103 /* we emit signals on the pad areg, the peer will have a chance to
3104 * emit in the _chain() function */
3105 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3107 gst_object_ref (peer);
3110 if (G_UNLIKELY (emit_signal)) {
3111 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3115 ret = gst_pad_chain (peer, buffer);
3117 gst_object_unref (peer);
3121 /* ERROR recovery here */
3124 gst_buffer_unref (buffer);
3125 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3126 "pushing, but it was not linked");
3128 return GST_FLOW_NOT_LINKED;
3132 gst_buffer_unref (buffer);
3133 gst_object_unref (peer);
3134 GST_DEBUG ("Dropping buffer due to FALSE probe return");
3140 * gst_pad_check_pull_range:
3141 * @pad: a sink #GstPad.
3143 * Checks if a #gst_pad_pull_range() can be performed on the peer
3144 * source pad. This function is used by plugins that want to check
3145 * if they can use random access on the peer source pad.
3147 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
3148 * if it needs to perform some logic to determine if pull_range is
3151 * Returns: a gboolean with the result.
3156 gst_pad_check_pull_range (GstPad * pad)
3160 GstPadCheckGetRangeFunction checkgetrangefunc;
3162 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3165 if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
3166 goto wrong_direction;
3168 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3171 gst_object_ref (peer);
3174 /* see note in above function */
3175 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
3176 /* FIXME, kindoff ghetto */
3177 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
3179 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3180 "calling checkgetrangefunc %s of peer pad %s:%s",
3181 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
3183 ret = checkgetrangefunc (peer);
3186 gst_object_unref (peer);
3190 /* ERROR recovery here */
3198 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3199 "checking pull range, but it was not linked");
3206 * gst_pad_get_range:
3207 * @pad: a src #GstPad.
3208 * @offset: The start offset of the buffer
3209 * @size: The length of the buffer
3210 * @buffer: a pointer to hold the #GstBuffer.
3212 * Calls the getrange function of @pad.
3214 * Returns: a #GstFlowReturn from the pad.
3219 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
3220 GstBuffer ** buffer)
3223 GstPadGetRangeFunction getrangefunc;
3224 gboolean emit_signal;
3226 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3227 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3228 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3230 GST_STREAM_LOCK (pad);
3233 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3236 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3239 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
3242 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3243 "calling getrangefunc %s of peer pad %s:%s, offset %"
3244 G_GUINT64_FORMAT ", size %u",
3245 GST_DEBUG_FUNCPTR_NAME (getrangefunc), GST_DEBUG_PAD_NAME (pad),
3248 ret = getrangefunc (pad, offset, size, buffer);
3250 /* can only fire the signal if we have a valid buffer */
3251 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3252 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3256 GST_STREAM_UNLOCK (pad);
3263 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3264 "pulling range, but pad was flushing");
3266 GST_STREAM_UNLOCK (pad);
3267 return GST_FLOW_WRONG_STATE;
3271 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3272 ("pullrange on pad %s:%s but it has no getrangefunction",
3273 GST_DEBUG_PAD_NAME (pad)));
3274 GST_STREAM_UNLOCK (pad);
3275 return GST_FLOW_ERROR;
3279 GST_DEBUG ("Dropping data after FALSE probe return");
3280 GST_STREAM_UNLOCK (pad);
3281 gst_buffer_unref (*buffer);
3283 return GST_FLOW_UNEXPECTED;
3289 * gst_pad_pull_range:
3290 * @pad: a sink #GstPad.
3291 * @offset: The start offset of the buffer
3292 * @size: The length of the buffer
3293 * @buffer: a pointer to hold the #GstBuffer.
3295 * Pulls a buffer from the peer pad. @pad must be a linked
3298 * Returns: a #GstFlowReturn from the peer pad.
3303 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
3304 GstBuffer ** buffer)
3308 gboolean emit_signal;
3310 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3311 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3313 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3317 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3318 handle_pad_block (pad);
3320 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3323 /* signal emision for the pad, peer has chance to emit when
3324 * we call _get_range() */
3325 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3327 gst_object_ref (peer);
3330 ret = gst_pad_get_range (peer, offset, size, buffer);
3332 gst_object_unref (peer);
3334 /* can only fire the signal if we have a valid buffer */
3335 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3336 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3341 /* ERROR recovery here */
3344 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3345 "pulling range, but it was not linked");
3347 return GST_FLOW_NOT_LINKED;
3351 GST_DEBUG ("Dropping data after FALSE probe return");
3352 gst_buffer_unref (*buffer);
3354 return GST_FLOW_UNEXPECTED;
3359 * gst_pad_push_event:
3360 * @pad: a #GstPad to push the event to.
3361 * @event: the #GstEvent to send to the pad.
3363 * Sends the event to the peer of the given pad. This function is
3364 * mainly used by elements to send events to their peer
3367 * Returns: TRUE if the event was handled.
3372 gst_pad_push_event (GstPad * pad, GstEvent * event)
3376 gboolean emit_signal;
3378 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3379 g_return_val_if_fail (event != NULL, FALSE);
3382 peerpad = GST_PAD_PEER (pad);
3383 if (peerpad == NULL)
3386 emit_signal = GST_PAD_DO_EVENT_SIGNALS (pad) > 0;
3388 gst_object_ref (peerpad);
3391 if (G_UNLIKELY (emit_signal)) {
3392 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3396 result = gst_pad_send_event (peerpad, event);
3398 gst_object_unref (peerpad);
3402 /* ERROR handling */
3405 gst_event_unref (event);
3411 GST_DEBUG ("Dropping event after FALSE probe return");
3412 gst_object_unref (peerpad);
3413 gst_event_unref (event);
3419 * gst_pad_send_event:
3420 * @pad: a #GstPad to send the event to.
3421 * @event: the #GstEvent to send to the pad.
3423 * Sends the event to the pad. This function can be used
3424 * by applications to send events in the pipeline.
3426 * Returns: TRUE if the event was handled.
3429 gst_pad_send_event (GstPad * pad, GstEvent * event)
3431 gboolean result = FALSE;
3432 GstPadEventFunction eventfunc;
3433 gboolean emit_signal;
3435 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3436 g_return_val_if_fail (event != NULL, FALSE);
3440 if (GST_PAD_IS_SINK (pad) && !GST_EVENT_IS_DOWNSTREAM (event))
3441 goto wrong_direction;
3442 if (GST_PAD_IS_SRC (pad) && !GST_EVENT_IS_UPSTREAM (event))
3443 goto wrong_direction;
3445 if (GST_EVENT_SRC (event) == NULL)
3446 GST_EVENT_SRC (event) = gst_object_ref (pad);
3448 switch (GST_EVENT_TYPE (event)) {
3449 case GST_EVENT_FLUSH_START:
3450 GST_CAT_DEBUG (GST_CAT_EVENT,
3451 "have event type %d (FLUSH_START) on pad %s:%s",
3452 GST_EVENT_TYPE (event), GST_DEBUG_PAD_NAME (pad));
3454 /* can't even accept a flush begin event when flushing */
3455 if (GST_PAD_IS_FLUSHING (pad))
3457 GST_PAD_SET_FLUSHING (pad);
3458 GST_CAT_DEBUG (GST_CAT_EVENT, "set flush flag");
3460 case GST_EVENT_FLUSH_STOP:
3461 GST_PAD_UNSET_FLUSHING (pad);
3462 GST_CAT_DEBUG (GST_CAT_EVENT, "cleared flush flag");
3465 GST_CAT_DEBUG (GST_CAT_EVENT, "have event type %d on pad %s:%s",
3466 GST_EVENT_TYPE (event), GST_DEBUG_PAD_NAME (pad));
3468 if (GST_PAD_IS_FLUSHING (pad))
3473 if ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL)
3476 emit_signal = GST_PAD_DO_EVENT_SIGNALS (pad) > 0;
3478 gst_object_ref (pad);
3481 if (G_UNLIKELY (emit_signal)) {
3482 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3486 result = eventfunc (GST_PAD_CAST (pad), event);
3488 gst_object_unref (pad);
3492 /* ERROR handling */
3495 g_warning ("pad %s:%s sending event in wrong direction",
3496 GST_DEBUG_PAD_NAME (pad));
3498 gst_event_unref (event);
3503 g_warning ("pad %s:%s has no event handler, file a bug.",
3504 GST_DEBUG_PAD_NAME (pad));
3506 gst_event_unref (event);
3512 GST_CAT_DEBUG (GST_CAT_EVENT, "Received event on flushing pad. Discarding");
3513 gst_event_unref (event);
3518 GST_DEBUG ("Dropping event after FALSE probe return");
3519 gst_object_unref (pad);
3520 gst_event_unref (event);
3526 * gst_pad_set_element_private:
3527 * @pad: the #GstPad to set the private data of.
3528 * @priv: The private data to attach to the pad.
3530 * Set the given private data gpointer on the pad.
3531 * This function can only be used by the element that owns the pad.
3534 gst_pad_set_element_private (GstPad * pad, gpointer priv)
3536 pad->element_private = priv;
3540 * gst_pad_get_element_private:
3541 * @pad: the #GstPad to get the private data of.
3543 * Gets the private data of a pad.
3545 * Returns: a #gpointer to the private data.
3548 gst_pad_get_element_private (GstPad * pad)
3550 return pad->element_private;
3554 * gst_pad_start_task:
3555 * @pad: the #GstPad to start the task of
3556 * @func: the task function to call
3557 * @data: data passed to the task function
3559 * Starts a task that repeadedly calls @func with @data. This function
3560 * is nostly used in the pad activation function to start the
3561 * dataflow. This function will automatically acauire the STREAM_LOCK of
3562 * the pad before calling @func.
3564 * Returns: a TRUE if the task could be started.
3567 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
3571 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3572 g_return_val_if_fail (func != NULL, FALSE);
3575 task = GST_PAD_TASK (pad);
3577 task = gst_task_create (func, data);
3578 gst_task_set_lock (task, GST_STREAM_GET_LOCK (pad));
3579 GST_PAD_TASK (pad) = task;
3581 gst_task_start (task);
3588 * gst_pad_pause_task:
3589 * @pad: the #GstPad to pause the task of
3591 * Pause the task of @pad. This function will also make sure that the
3592 * function executed by the task will effectively stop.
3594 * Returns: a TRUE if the task could be paused or FALSE when the pad
3598 gst_pad_pause_task (GstPad * pad)
3602 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3605 task = GST_PAD_TASK (pad);
3608 gst_task_pause (task);
3611 GST_STREAM_LOCK (pad);
3612 GST_STREAM_UNLOCK (pad);
3624 * gst_pad_stop_task:
3625 * @pad: the #GstPad to stop the task of
3627 * Stop the task of @pad. This function will also make sure that the
3628 * function executed by the task will effectively stop if not called
3629 * from the GstTaskFunction.
3631 * This function will deadlock if called from the GstTaskFunction of
3632 * the task. Use #gst_task_pause() instead.
3634 * Returns: a TRUE if the task could be stopped or FALSE when the pad
3638 gst_pad_stop_task (GstPad * pad)
3642 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3645 task = GST_PAD_TASK (pad);
3648 GST_PAD_TASK (pad) = NULL;
3649 gst_task_stop (task);
3652 GST_STREAM_LOCK (pad);
3653 GST_STREAM_UNLOCK (pad);
3655 gst_task_join (task);
3657 gst_object_unref (task);