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 whether the pad should be blocked or unblocked
770 * @callback: #GstPadBlockCallback that will be called when the
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 happens right before the next
776 * attempt at pushing a buffer on the pad.
778 * This can take a while as
779 * the pad can only become blocked when real dataflow is happening.
780 * When the pipeline is stalled, for example in PAUSED, this can
781 * take an indeterminate amount of time.
782 * You can pass NULL as the callback to make this call block. Be
783 * carefull with this blocking call as it might not return for
784 * reasons stated above.
786 * Returns: TRUE if the pad could be blocked. This function can fail
787 * if wrong parameters were passed or the pad was already in the
793 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
794 GstPadBlockCallback callback, gpointer user_data)
796 gboolean was_blocked;
798 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
802 was_blocked = GST_PAD_IS_BLOCKED (pad);
804 if (G_UNLIKELY (was_blocked == blocked))
805 goto had_right_state;
808 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad %s:%s",
809 GST_DEBUG_PAD_NAME (pad));
811 GST_FLAG_SET (pad, GST_PAD_BLOCKED);
812 pad->block_callback = callback;
813 pad->block_data = user_data;
815 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
816 GST_PAD_BLOCK_WAIT (pad);
817 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
820 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad %s:%s",
821 GST_DEBUG_PAD_NAME (pad));
823 GST_FLAG_UNSET (pad, GST_PAD_BLOCKED);
825 pad->block_callback = callback;
826 pad->block_data = user_data;
829 GST_PAD_BLOCK_SIGNAL (pad);
831 GST_PAD_BLOCK_SIGNAL (pad);
832 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
833 GST_PAD_BLOCK_WAIT (pad);
834 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
843 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
844 "pad %s:%s was in right state", GST_DEBUG_PAD_NAME (pad));
851 * gst_pad_set_blocked:
852 * @pad: the #GstPad to block or unblock
853 * @blocked: boolean indicating we should block or unblock
855 * Blocks or unblocks the dataflow on a pad. This function is
856 * a shortcut for @gst_pad_set_blocked_async() with a NULL
859 * Returns: TRUE if the pad could be blocked. This function can fail
860 * wrong parameters were passed or the pad was already in the
866 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
868 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
872 * gst_pad_is_blocked:
873 * @pad: the #GstPad to query
875 * Checks if the pad is blocked or not. This function returns the
876 * last requested state of the pad. It is not certain that the pad
877 * is actually blocked at this point.
879 * Returns: TRUE if the pad is blocked.
884 gst_pad_is_blocked (GstPad * pad)
886 gboolean result = FALSE;
888 g_return_val_if_fail (GST_IS_PAD (pad), result);
891 result = GST_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
898 * gst_pad_set_activate_function:
899 * @pad: a sink #GstPad.
900 * @activate: the #GstPadActivateFunction to set.
902 * Sets the given activate function for the pad. The activate function will
903 * dispatch to activate_push or activate_pull to perform the actual activation.
904 * Only makes sense to set on sink pads.
906 * Call this function if your sink pad can start a pull-based task.
909 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
911 g_return_if_fail (GST_IS_PAD (pad));
913 GST_PAD_ACTIVATEFUNC (pad) = activate;
914 GST_CAT_DEBUG (GST_CAT_PADS, "activatefunc for %s:%s set to %s",
915 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activate));
919 * gst_pad_set_activatepull_function:
920 * @pad: a sink #GstPad.
921 * @activatepull: the #GstPadActivateModeFunction to set.
923 * Sets the given activate_pull function for the pad. An activate_pull function
924 * prepares the element and any upstream connections for pulling. See XXX
925 * part-activation.txt for details.
928 gst_pad_set_activatepull_function (GstPad * pad,
929 GstPadActivateModeFunction activatepull)
931 g_return_if_fail (GST_IS_PAD (pad));
933 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
934 GST_CAT_DEBUG (GST_CAT_PADS, "activatepullfunc for %s:%s set to %s",
935 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activatepull));
939 * gst_pad_set_activatepush_function:
940 * @pad: a sink #GstPad.
941 * @activatepush: the #GstPadActivateModeFunction to set.
943 * Sets the given activate_push function for the pad. An activate_push function
944 * prepares the element for pushing. See XXX part-activation.txt for details.
947 gst_pad_set_activatepush_function (GstPad * pad,
948 GstPadActivateModeFunction activatepush)
950 g_return_if_fail (GST_IS_PAD (pad));
952 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
953 GST_CAT_DEBUG (GST_CAT_PADS, "activatepushfunc for %s:%s set to %s",
954 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (activatepush));
958 * gst_pad_set_chain_function:
959 * @pad: a sink #GstPad.
960 * @chain: the #GstPadChainFunction to set.
962 * Sets the given chain function for the pad. The chain function is called to
963 * process a #GstBuffer input buffer.
966 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
968 g_return_if_fail (GST_IS_PAD (pad));
969 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
971 GST_PAD_CHAINFUNC (pad) = chain;
972 GST_CAT_DEBUG (GST_CAT_PADS, "chainfunc for %s:%s set to %s",
973 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (chain));
977 * gst_pad_set_getrange_function:
978 * @pad: a source #GstPad.
979 * @get: the #GstPadGetRangeFunction to set.
981 * Sets the given getrange function for the pad. The getrange function is called to
982 * produce a new #GstBuffer to start the processing pipeline. Getrange functions cannot
986 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
988 g_return_if_fail (GST_IS_PAD (pad));
989 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
991 GST_PAD_GETRANGEFUNC (pad) = get;
993 GST_CAT_DEBUG (GST_CAT_PADS, "getrangefunc for %s:%s set to %s",
994 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (get));
998 * gst_pad_set_checkgetrange_function:
999 * @pad: a source #GstPad.
1000 * @check: the #GstPadCheckGetRangeFunction to set.
1002 * Sets the given checkgetrange function for the pad. Implement this function on
1003 * a pad if you dynamically support getrange based scheduling on the pad.
1006 gst_pad_set_checkgetrange_function (GstPad * pad,
1007 GstPadCheckGetRangeFunction check)
1009 g_return_if_fail (GST_IS_PAD (pad));
1010 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1012 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1014 GST_CAT_DEBUG (GST_CAT_PADS, "checkgetrangefunc for %s:%s set to %s",
1015 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (check));
1019 * gst_pad_set_event_function:
1020 * @pad: a source #GstPad.
1021 * @event: the #GstPadEventFunction to set.
1023 * Sets the given event handler for the pad.
1026 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1028 g_return_if_fail (GST_IS_PAD (pad));
1030 GST_PAD_EVENTFUNC (pad) = event;
1032 GST_CAT_DEBUG (GST_CAT_PADS, "eventfunc for %s:%s set to %s",
1033 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (event));
1037 * gst_pad_set_query_function:
1038 * @pad: a #GstPad of either direction.
1039 * @query: the #GstPadQueryFunction to set.
1041 * Set the given query function for the pad.
1044 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1046 g_return_if_fail (GST_IS_PAD (pad));
1048 GST_PAD_QUERYFUNC (pad) = query;
1050 GST_CAT_DEBUG (GST_CAT_PADS, "queryfunc for %s:%s set to %s",
1051 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (query));
1055 * gst_pad_set_query_type_function:
1056 * @pad: a #GstPad of either direction.
1057 * @type_func: the #GstPadQueryTypeFunction to set.
1059 * Set the given query type function for the pad.
1062 gst_pad_set_query_type_function (GstPad * pad,
1063 GstPadQueryTypeFunction type_func)
1065 g_return_if_fail (GST_IS_PAD (pad));
1067 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1069 GST_CAT_DEBUG (GST_CAT_PADS, "querytypefunc for %s:%s set to %s",
1070 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (type_func));
1074 * gst_pad_get_query_types:
1077 * Get an array of supported queries that can be performed
1080 * Returns: a zero-terminated array of #GstQueryType.
1082 const GstQueryType *
1083 gst_pad_get_query_types (GstPad * pad)
1085 GstPadQueryTypeFunction func;
1087 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1089 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1101 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1103 *data = gst_pad_get_query_types (pad);
1109 * gst_pad_get_query_types_default:
1112 * Invoke the default dispatcher for the query types on
1115 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1116 * internally-linked pads has a query types function.
1118 const GstQueryType *
1119 gst_pad_get_query_types_default (GstPad * pad)
1121 GstQueryType *result = NULL;
1123 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1125 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1126 gst_pad_get_query_types_dispatcher, &result);
1132 * gst_pad_set_internal_link_function:
1133 * @pad: a #GstPad of either direction.
1134 * @intlink: the #GstPadIntLinkFunction to set.
1136 * Sets the given internal link function for the pad.
1139 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1141 g_return_if_fail (GST_IS_PAD (pad));
1143 GST_PAD_INTLINKFUNC (pad) = intlink;
1144 GST_CAT_DEBUG (GST_CAT_PADS, "internal link for %s:%s set to %s",
1145 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (intlink));
1149 * gst_pad_set_link_function:
1151 * @link: the #GstPadLinkFunction to set.
1153 * Sets the given link function for the pad. It will be called when the pad is
1154 * linked or relinked with caps. The caps passed to the link function is
1155 * the caps for the connnection. It can contain a non fixed caps.
1157 * The return value GST_PAD_LINK_OK should be used when the connection can be
1160 * The return value GST_PAD_LINK_REFUSED should be used when the connection
1161 * cannot be made for some reason.
1164 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1166 g_return_if_fail (GST_IS_PAD (pad));
1168 GST_PAD_LINKFUNC (pad) = link;
1169 GST_CAT_DEBUG (GST_CAT_PADS, "linkfunc for %s:%s set to %s",
1170 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (link));
1174 * gst_pad_set_unlink_function:
1176 * @unlink: the #GstPadUnlinkFunction to set.
1178 * Sets the given unlink function for the pad. It will be called
1179 * when the pad is unlinked.
1182 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1184 g_return_if_fail (GST_IS_PAD (pad));
1186 GST_PAD_UNLINKFUNC (pad) = unlink;
1187 GST_CAT_DEBUG (GST_CAT_PADS, "unlinkfunc for %s:%s set to %s",
1188 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (unlink));
1192 * gst_pad_set_getcaps_function:
1194 * @getcaps: the #GstPadGetCapsFunction to set.
1196 * Sets the given getcaps function for the pad. @getcaps should return the
1197 * allowable caps for a pad in the context of the element's state, its link to
1198 * other elements, and the devices or files it has opened. These caps must be a
1199 * subset of the pad template caps. In the NULL state with no links, @getcaps
1200 * should ideally return the same caps as the pad template. In rare
1201 * circumstances, an object property can affect the caps returned by @getcaps,
1202 * but this is discouraged.
1204 * You do not need to call this function if @pad's allowed caps are always the
1205 * same as the pad template caps. This can only be true if the padtemplate
1206 * has fixed simple caps.
1208 * For most filters, the caps returned by @getcaps is directly affected by the
1209 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1210 * the srcpad's getcaps function is directly related to the stream data. Again,
1211 * @getcaps should return the most specific caps it reasonably can, since this
1212 * helps with autoplugging.
1214 * Note that the return value from @getcaps is owned by the caller, so the caller
1215 * should unref the caps after usage.
1218 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1220 g_return_if_fail (GST_IS_PAD (pad));
1222 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1223 GST_CAT_DEBUG (GST_CAT_PADS, "getcapsfunc for %s:%s set to %s",
1224 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (getcaps));
1228 * gst_pad_set_acceptcaps_function:
1230 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1232 * Sets the given acceptcaps function for the pad. The acceptcaps function
1233 * will be called to check if the pad can accept the given caps.
1236 gst_pad_set_acceptcaps_function (GstPad * pad,
1237 GstPadAcceptCapsFunction acceptcaps)
1239 g_return_if_fail (GST_IS_PAD (pad));
1241 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1242 GST_CAT_DEBUG (GST_CAT_PADS, "acceptcapsfunc for %s:%s set to %s",
1243 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1247 * gst_pad_set_fixatecaps_function:
1249 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1251 * Sets the given fixatecaps function for the pad. The fixatecaps function
1252 * will be called whenever the default values for a GstCaps needs to be
1256 gst_pad_set_fixatecaps_function (GstPad * pad,
1257 GstPadFixateCapsFunction fixatecaps)
1259 g_return_if_fail (GST_IS_PAD (pad));
1261 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1262 GST_CAT_DEBUG (GST_CAT_PADS, "fixatecapsfunc for %s:%s set to %s",
1263 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1267 * gst_pad_set_setcaps_function:
1269 * @setcaps: the #GstPadSetCapsFunction to set.
1271 * Sets the given setcaps function for the pad. The setcaps function
1272 * will be called whenever a buffer with a new media type is pushed or
1273 * pulled from the pad. The pad/element needs to update it's internal
1274 * structures to process the new media type. If this new type is not
1275 * acceptable, the setcaps function should return FALSE.
1278 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1280 g_return_if_fail (GST_IS_PAD (pad));
1282 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1283 GST_CAT_DEBUG (GST_CAT_PADS, "setcapsfunc for %s:%s set to %s",
1284 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (setcaps));
1288 * gst_pad_set_bufferalloc_function:
1289 * @pad: a sink #GstPad.
1290 * @bufalloc: the #GstPadBufferAllocFunction to set.
1292 * Sets the given bufferalloc function for the pad. Note that the
1293 * bufferalloc function can only be set on sinkpads.
1296 gst_pad_set_bufferalloc_function (GstPad * pad,
1297 GstPadBufferAllocFunction bufalloc)
1299 g_return_if_fail (GST_IS_PAD (pad));
1300 g_return_if_fail (GST_PAD_IS_SINK (pad));
1302 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1303 GST_CAT_DEBUG (GST_CAT_PADS, "bufferallocfunc for %s:%s set to %s",
1304 GST_DEBUG_PAD_NAME (pad), GST_DEBUG_FUNCPTR_NAME (bufalloc));
1309 * @srcpad: the source #GstPad to unlink.
1310 * @sinkpad: the sink #GstPad to unlink.
1312 * Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
1315 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1316 * the pads were not linked together.
1321 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1323 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1324 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1326 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1327 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1328 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1332 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1337 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1340 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1341 goto not_linked_together;
1343 if (GST_PAD_UNLINKFUNC (srcpad)) {
1344 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1346 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1347 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1350 /* first clear peers */
1351 GST_PAD_PEER (srcpad) = NULL;
1352 GST_PAD_PEER (sinkpad) = NULL;
1354 GST_UNLOCK (sinkpad);
1355 GST_UNLOCK (srcpad);
1357 /* fire off a signal to each of the pads telling them
1358 * that they've been unlinked */
1359 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1360 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1362 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1363 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1369 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1370 GST_UNLOCK (srcpad);
1375 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1376 GST_UNLOCK (sinkpad);
1377 GST_UNLOCK (srcpad);
1380 not_linked_together:
1382 /* we do not emit a warning in this case because unlinking cannot
1383 * be made MT safe.*/
1384 GST_UNLOCK (sinkpad);
1385 GST_UNLOCK (srcpad);
1391 * gst_pad_is_linked:
1392 * @pad: pad to check
1394 * Checks if a @pad is linked to another pad or not.
1396 * Returns: TRUE if the pad is linked, FALSE otherwise.
1401 gst_pad_is_linked (GstPad * pad)
1405 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1408 result = (GST_PAD_PEER (pad) != NULL);
1414 /* get the caps from both pads and see if the intersection
1417 * This function should be called with the pad LOCK on both
1421 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1426 srccaps = gst_pad_get_caps_unlocked (src);
1427 sinkcaps = gst_pad_get_caps_unlocked (sink);
1428 GST_CAT_DEBUG (GST_CAT_CAPS, " src caps %" GST_PTR_FORMAT, srccaps);
1429 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1431 /* if we have caps on both pads we can check the intersection */
1432 if (srccaps && sinkcaps) {
1435 icaps = gst_caps_intersect (srccaps, sinkcaps);
1436 gst_caps_unref (srccaps);
1437 gst_caps_unref (sinkcaps);
1439 GST_CAT_DEBUG (GST_CAT_CAPS,
1440 "intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
1442 if (!icaps || gst_caps_is_empty (icaps)) {
1443 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is empty");
1444 gst_caps_unref (icaps);
1447 gst_caps_unref (icaps);
1453 /* check if the grandparents of both pads are the same.
1454 * This check is required so that we don't try to link
1455 * pads from elements in different bins without ghostpads.
1457 * The LOCK should be helt on both pads
1460 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1462 GstObject *psrc, *psink;
1463 gboolean res = TRUE;
1465 psrc = GST_OBJECT_PARENT (src);
1466 psink = GST_OBJECT_PARENT (sink);
1468 /* if one of the pads has no parent, we allow the link */
1469 if (psrc && psink) {
1470 /* if the parents are the same, we have a loop */
1471 if (psrc == psink) {
1472 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1477 /* if they both have a parent, we check the grandparents */
1478 psrc = gst_object_get_parent (psrc);
1479 psink = gst_object_get_parent (psink);
1481 if (psrc != psink) {
1482 /* if they have grandparents but they are not the same */
1483 GST_CAT_DEBUG (GST_CAT_CAPS,
1484 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1485 GST_PTR_FORMAT, psrc, psink);
1489 gst_object_unref (psrc);
1491 gst_object_unref (psink);
1497 /* FIXME leftover from an attempt at refactoring... */
1498 /* call with the two pads unlocked */
1499 static GstPadLinkReturn
1500 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1502 /* generic checks */
1503 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
1504 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
1506 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1507 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1511 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1514 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1515 goto src_was_linked;
1519 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1522 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1523 goto sink_was_linked;
1525 /* check hierarchy, pads can only be linked if the grandparents
1527 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1528 goto wrong_hierarchy;
1530 /* check pad caps for non-empty intersection */
1531 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1534 /* FIXME check pad scheduling for non-empty intersection */
1536 return GST_PAD_LINK_OK;
1540 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1541 GST_UNLOCK (srcpad);
1542 return GST_PAD_LINK_WRONG_DIRECTION;
1546 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was linked",
1547 GST_DEBUG_PAD_NAME (srcpad));
1548 /* we do not emit a warning in this case because unlinking cannot
1549 * be made MT safe.*/
1550 GST_UNLOCK (srcpad);
1551 return GST_PAD_LINK_WAS_LINKED;
1555 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1556 GST_UNLOCK (sinkpad);
1557 GST_UNLOCK (srcpad);
1558 return GST_PAD_LINK_WRONG_DIRECTION;
1562 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was linked",
1563 GST_DEBUG_PAD_NAME (sinkpad));
1564 /* we do not emit a warning in this case because unlinking cannot
1565 * be made MT safe.*/
1566 GST_UNLOCK (sinkpad);
1567 GST_UNLOCK (srcpad);
1568 return GST_PAD_LINK_WAS_LINKED;
1572 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1573 GST_UNLOCK (sinkpad);
1574 GST_UNLOCK (srcpad);
1575 return GST_PAD_LINK_WRONG_HIERARCHY;
1579 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1580 GST_UNLOCK (sinkpad);
1581 GST_UNLOCK (srcpad);
1582 return GST_PAD_LINK_NOFORMAT;
1588 * @srcpad: the source #GstPad to link.
1589 * @sinkpad: the sink #GstPad to link.
1591 * Links the source pad and the sink pad.
1593 * Returns: A result code indicating if the connection worked or
1599 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1601 GstPadLinkReturn result;
1603 /* prepare will also lock the two pads */
1604 result = gst_pad_link_prepare (srcpad, sinkpad);
1606 if (result != GST_PAD_LINK_OK)
1607 goto prepare_failed;
1609 GST_UNLOCK (sinkpad);
1610 GST_UNLOCK (srcpad);
1612 /* FIXME released the locks here, concurrent thread might link
1613 * something else. */
1614 if (GST_PAD_LINKFUNC (srcpad)) {
1615 /* this one will call the peer link function */
1616 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
1617 } else if (GST_PAD_LINKFUNC (sinkpad)) {
1618 /* if no source link function, we need to call the sink link
1619 * function ourselves. */
1620 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
1622 result = GST_PAD_LINK_OK;
1628 if (result == GST_PAD_LINK_OK) {
1629 GST_PAD_PEER (srcpad) = sinkpad;
1630 GST_PAD_PEER (sinkpad) = srcpad;
1632 GST_UNLOCK (sinkpad);
1633 GST_UNLOCK (srcpad);
1635 /* fire off a signal to each of the pads telling them
1636 * that they've been linked */
1637 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
1638 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
1640 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
1641 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1643 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
1644 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1646 GST_UNLOCK (sinkpad);
1647 GST_UNLOCK (srcpad);
1658 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
1660 /* this function would need checks if it weren't static */
1663 gst_object_replace ((GstObject **) & pad->padtemplate, (GstObject *) templ);
1667 gst_pad_template_pad_created (templ, pad);
1671 * gst_pad_get_pad_template:
1674 * Gets the template for @pad.
1676 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
1677 * if this pad has no template.
1679 * FIXME: currently returns an unrefcounted padtemplate.
1682 gst_pad_get_pad_template (GstPad * pad)
1684 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1686 return GST_PAD_PAD_TEMPLATE (pad);
1690 /* should be called with the pad LOCK held */
1691 /* refs the caps, so caller is responsible for getting it unreffed */
1693 gst_pad_get_caps_unlocked (GstPad * pad)
1695 GstCaps *result = NULL;
1697 GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
1698 GST_DEBUG_PAD_NAME (pad), pad);
1700 if (GST_PAD_GETCAPSFUNC (pad)) {
1701 GST_CAT_DEBUG (GST_CAT_CAPS, "dispatching to pad getcaps function");
1703 GST_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
1705 result = GST_PAD_GETCAPSFUNC (pad) (pad);
1707 GST_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
1709 if (result == NULL) {
1710 g_critical ("pad %s:%s returned NULL caps from getcaps function",
1711 GST_DEBUG_PAD_NAME (pad));
1713 GST_CAT_DEBUG (GST_CAT_CAPS,
1714 "pad getcaps %s:%s returned %" GST_PTR_FORMAT,
1715 GST_DEBUG_PAD_NAME (pad), result);
1716 #ifndef G_DISABLE_ASSERT
1717 /* check that the returned caps are a real subset of the template caps */
1718 if (GST_PAD_PAD_TEMPLATE (pad)) {
1719 const GstCaps *templ_caps =
1720 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
1721 if (!gst_caps_is_subset (result, templ_caps)) {
1724 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
1725 "pad returned caps %" GST_PTR_FORMAT
1726 " which are not a real subset of its template caps %"
1727 GST_PTR_FORMAT, result, templ_caps);
1729 ("pad %s:%s returned caps that are not a real subset of its template caps",
1730 GST_DEBUG_PAD_NAME (pad));
1731 temp = gst_caps_intersect (templ_caps, result);
1732 gst_caps_unref (result);
1740 if (GST_PAD_PAD_TEMPLATE (pad)) {
1741 GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
1743 result = GST_PAD_TEMPLATE_CAPS (templ);
1744 GST_CAT_DEBUG (GST_CAT_CAPS,
1745 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
1748 result = gst_caps_ref (result);
1751 if (GST_PAD_CAPS (pad)) {
1752 result = GST_PAD_CAPS (pad);
1754 GST_CAT_DEBUG (GST_CAT_CAPS,
1755 "using pad caps %p %" GST_PTR_FORMAT, result, result);
1757 result = gst_caps_ref (result);
1761 GST_CAT_DEBUG (GST_CAT_CAPS, "pad has no caps");
1762 result = gst_caps_new_empty ();
1770 * @pad: a #GstPad to get the capabilities of.
1772 * Gets the capabilities this pad can produce or consume.
1773 * Note that this method doesn't necessarily returns the caps set by
1774 * #gst_pad_set_caps - use #GST_PAD_CAPS for that instead.
1775 * gst_pad_get_caps returns all possible caps a pad can operate with, using
1776 * the pad's get_caps function;
1777 * this returns the pad template caps if not explicitly set.
1779 * Returns: a newly allocated copy of the #GstCaps of this pad.
1784 gst_pad_get_caps (GstPad * pad)
1786 GstCaps *result = NULL;
1788 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1792 GST_CAT_DEBUG (GST_CAT_CAPS, "get pad caps of %s:%s (%p)",
1793 GST_DEBUG_PAD_NAME (pad), pad);
1795 if (G_UNLIKELY (GST_PAD_IS_IN_GETCAPS (pad)))
1796 goto was_dispatching;
1798 result = gst_pad_get_caps_unlocked (pad);
1805 GST_CAT_DEBUG (GST_CAT_CAPS,
1806 "pad %s:%s is already dispatching!", GST_DEBUG_PAD_NAME (pad));
1807 g_warning ("pad %s:%s recursively called getcaps!",
1808 GST_DEBUG_PAD_NAME (pad));
1815 * gst_pad_peer_get_caps:
1816 * @pad: a #GstPad to get the peer capabilities of.
1818 * Gets the capabilities of the peer connected to this pad.
1820 * Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
1821 * gst_caps_unref to get rid of it. this function returns NULL if there is no
1822 * peer pad or when this function is called recursively from a getcaps function.
1825 gst_pad_peer_get_caps (GstPad * pad)
1828 GstCaps *result = NULL;
1830 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1834 GST_CAT_DEBUG (GST_CAT_CAPS, "get peer caps of %s:%s (%p)",
1835 GST_DEBUG_PAD_NAME (pad), pad);
1837 peerpad = GST_PAD_PEER (pad);
1838 if (G_UNLIKELY (peerpad == NULL))
1841 if (G_UNLIKELY (GST_PAD_IS_IN_GETCAPS (peerpad)))
1842 goto was_dispatching;
1844 gst_object_ref (peerpad);
1847 result = gst_pad_get_caps (peerpad);
1849 gst_object_unref (peerpad);
1860 GST_CAT_DEBUG (GST_CAT_CAPS,
1861 "pad %s:%s is already dispatching!", GST_DEBUG_PAD_NAME (pad));
1862 g_warning ("pad %s:%s recursively called getcaps!",
1863 GST_DEBUG_PAD_NAME (pad));
1870 fixate_value (GValue * dest, const GValue * src)
1872 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
1873 g_value_init (dest, G_TYPE_INT);
1874 g_value_set_int (dest, gst_value_get_int_range_min (src));
1875 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
1876 g_value_init (dest, G_TYPE_DOUBLE);
1877 g_value_set_double (dest, gst_value_get_double_range_min (src));
1878 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
1879 GValue temp = { 0 };
1881 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
1882 if (!fixate_value (dest, &temp))
1883 gst_value_init_and_copy (dest, &temp);
1884 g_value_unset (&temp);
1885 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
1886 gboolean res = FALSE;
1889 g_value_init (dest, GST_TYPE_ARRAY);
1890 for (n = 0; n < gst_value_list_get_size (src); n++) {
1892 const GValue *orig_kid = gst_value_list_get_value (src, n);
1894 if (!fixate_value (&kid, orig_kid))
1895 gst_value_init_and_copy (&kid, orig_kid);
1898 gst_value_list_append_value (dest, &kid);
1899 g_value_unset (&kid);
1903 g_value_unset (dest);
1914 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
1916 GstStructure *s = data;
1919 if (fixate_value (&v, value)) {
1920 gst_structure_id_set_value (s, field_id, &v);
1928 * gst_pad_fixate_caps:
1929 * @pad: a #GstPad to fixate
1930 * @caps: the #GstCaps to fixate
1932 * Fixate a caps on the given pad. Modifies the caps in place, so you should
1933 * make sure that the caps are actually writable (see gst_caps_make_writable()).
1936 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
1938 GstPadFixateCapsFunction fixatefunc;
1941 g_return_if_fail (GST_IS_PAD (pad));
1942 g_return_if_fail (caps != NULL);
1944 if (gst_caps_is_fixed (caps))
1947 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
1949 fixatefunc (pad, caps);
1952 /* default fixation */
1953 for (n = 0; n < gst_caps_get_size (caps); n++) {
1954 GstStructure *s = gst_caps_get_structure (caps, n);
1956 gst_structure_foreach (s, gst_pad_default_fixate, s);
1961 * gst_pad_accept_caps:
1962 * @pad: a #GstPad to check
1963 * @caps: a #GstCaps to check on the pad
1965 * Check if the given pad accepts the caps.
1967 * Returns: TRUE if the pad can accept the caps.
1970 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
1973 GstPadAcceptCapsFunction acceptfunc;
1975 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1977 /* any pad can be unnegotiated */
1982 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
1984 GST_CAT_DEBUG (GST_CAT_CAPS, "pad accept caps of %s:%s (%p)",
1985 GST_DEBUG_PAD_NAME (pad), pad);
1989 /* we can call the function */
1990 result = acceptfunc (pad, caps);
1992 /* else see get the caps and see if it intersects to something
1997 allowed = gst_pad_get_caps (pad);
1999 intersect = gst_caps_intersect (allowed, caps);
2001 result = !gst_caps_is_empty (intersect);
2003 gst_caps_unref (allowed);
2004 gst_caps_unref (intersect);
2013 * gst_pad_peer_accept_caps:
2014 * @pad: a #GstPad to check
2015 * @caps: a #GstCaps to check on the pad
2017 * Check if the given pad accepts the caps.
2019 * Returns: TRUE if the pad can accept the caps.
2022 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2027 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2031 GST_CAT_DEBUG (GST_CAT_CAPS, "peer accept caps of %s:%s (%p)",
2032 GST_DEBUG_PAD_NAME (pad), pad);
2034 peerpad = GST_PAD_PEER (pad);
2035 if (G_UNLIKELY (peerpad == NULL))
2038 result = gst_pad_accept_caps (peerpad, caps);
2052 * @pad: a #GstPad to set the capabilities of.
2053 * @caps: a #GstCaps to set.
2055 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2056 * caps on the pad will be unreffed. This function refs the caps so you should
2057 * unref if as soon as you don't need it anymore.
2058 * It is possible to set NULL caps, which will make the pad unnegotiated
2061 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2062 * or bad parameters were provided to this function.
2067 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2069 GstPadSetCapsFunction setcaps;
2072 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2073 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2076 setcaps = GST_PAD_SETCAPSFUNC (pad);
2078 existing = GST_PAD_CAPS (pad);
2079 if (caps == existing)
2080 goto setting_same_caps;
2081 else if (caps && existing && gst_caps_is_equal (caps, existing))
2082 goto setting_same_caps;
2084 /* call setcaps function to configure the pad */
2085 if (setcaps != NULL && caps) {
2086 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2087 GST_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2089 if (!setcaps (pad, caps))
2092 GST_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2094 GST_CAT_DEBUG (GST_CAT_CAPS, "pad %s:%s was dispatching",
2095 GST_DEBUG_PAD_NAME (pad));
2099 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2100 GST_CAT_DEBUG (GST_CAT_CAPS, "%s:%s caps %" GST_PTR_FORMAT,
2101 GST_DEBUG_PAD_NAME (pad), caps);
2104 g_object_notify (G_OBJECT (pad), "caps");
2111 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2112 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2113 "caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
2120 GST_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2121 GST_CAT_DEBUG (GST_CAT_CAPS,
2122 "pad %s:%s, caps %" GST_PTR_FORMAT " could not be set",
2123 GST_DEBUG_PAD_NAME (pad), caps);
2131 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2133 GstPadAcceptCapsFunction acceptcaps;
2134 GstPadSetCapsFunction setcaps;
2137 acceptcaps = GST_PAD_ACCEPTCAPSFUNC (pad);
2138 setcaps = GST_PAD_SETCAPSFUNC (pad);
2140 /* See if pad accepts the caps, by calling acceptcaps, only
2141 * needed if no setcaps function */
2142 if (setcaps == NULL && acceptcaps != NULL) {
2143 if (!acceptcaps (pad, caps))
2146 /* set caps on pad if call succeeds */
2147 res = gst_pad_set_caps (pad, caps);
2148 /* no need to unref the caps here, set_caps takes a ref and
2149 * our ref goes away when we leave this function. */
2155 GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
2160 /* returns TRUE if the src pad could be configured to accept the given caps */
2162 gst_pad_configure_src (GstPad * pad, GstCaps * caps)
2164 GstPadAcceptCapsFunction acceptcaps;
2165 GstPadSetCapsFunction setcaps;
2168 acceptcaps = GST_PAD_ACCEPTCAPSFUNC (pad);
2169 setcaps = GST_PAD_SETCAPSFUNC (pad);
2171 /* See if pad accepts the caps, by calling acceptcaps, only
2172 * needed if no setcaps function */
2173 if (setcaps == NULL && acceptcaps != NULL) {
2174 if (!acceptcaps (pad, caps))
2177 /* set caps on pad if call succeeds */
2178 res = gst_pad_set_caps (pad, caps);
2179 /* no need to unref the caps here, set_caps takes a ref and
2180 * our ref goes away when we leave this function. */
2186 GST_CAT_DEBUG (GST_CAT_CAPS, "caps %" GST_PTR_FORMAT " not accepted", caps);
2192 * gst_pad_get_pad_template_caps:
2193 * @pad: a #GstPad to get the template capabilities from.
2195 * Gets the capabilities for @pad's template.
2197 * Returns: the #GstCaps of this pad template. If you intend to keep a reference
2198 * on the caps, make a copy (see gst_caps_copy ()).
2201 gst_pad_get_pad_template_caps (GstPad * pad)
2203 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2205 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2207 if (GST_PAD_PAD_TEMPLATE (pad))
2208 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2210 return gst_static_caps_get (&anycaps);
2216 * @pad: a #GstPad to get the peer of.
2218 * Gets the peer of @pad. This function refs the peer pad so
2219 * you need to unref it after use.
2221 * Returns: the peer #GstPad. Unref after usage.
2226 gst_pad_get_peer (GstPad * pad)
2230 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2233 result = GST_PAD_PEER (pad);
2235 gst_object_ref (result);
2242 * gst_pad_get_allowed_caps:
2243 * @srcpad: a #GstPad, it must a a source pad.
2245 * Gets the capabilities of the allowed media types that can flow through
2246 * @srcpad and its peer. The pad must be a source pad.
2247 * The caller must free the resulting caps.
2249 * Returns: the allowed #GstCaps of the pad link. Free the caps when
2250 * you no longer need it. This function returns NULL when the @srcpad has no
2256 gst_pad_get_allowed_caps (GstPad * srcpad)
2263 g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
2264 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
2268 peer = GST_PAD_PEER (srcpad);
2269 if (G_UNLIKELY (peer == NULL))
2272 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting allowed caps",
2273 GST_DEBUG_PAD_NAME (srcpad));
2275 gst_object_ref (peer);
2276 GST_UNLOCK (srcpad);
2277 mycaps = gst_pad_get_caps (srcpad);
2279 peercaps = gst_pad_get_caps (peer);
2280 gst_object_unref (peer);
2282 caps = gst_caps_intersect (mycaps, peercaps);
2283 gst_caps_unref (peercaps);
2284 gst_caps_unref (mycaps);
2286 GST_CAT_DEBUG (GST_CAT_CAPS, "allowed caps %" GST_PTR_FORMAT, caps);
2292 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
2293 GST_DEBUG_PAD_NAME (srcpad));
2294 GST_UNLOCK (srcpad);
2301 * gst_pad_get_negotiated_caps:
2304 * Gets the capabilities of the media type that currently flows through @pad
2307 * This function can be used on both src and sinkpads. Note that srcpads are
2308 * always negotiated before sinkpads so it is possible that the negotiated caps
2309 * on the srcpad do not match the negotiated caps of the peer.
2311 * Returns: the negotiated #GstCaps of the pad link. Free the caps when
2312 * you no longer need it. This function returns NULL when the @pad has no
2313 * peer or is not negotiated yet.
2318 gst_pad_get_negotiated_caps (GstPad * pad)
2323 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2327 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2330 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: getting negotiated caps",
2331 GST_DEBUG_PAD_NAME (pad));
2333 caps = GST_PAD_CAPS (pad);
2335 gst_caps_ref (caps);
2338 GST_CAT_DEBUG (GST_CAT_CAPS, "negotiated caps %" GST_PTR_FORMAT, caps);
2344 GST_CAT_DEBUG (GST_CAT_PROPERTIES, "%s:%s: no peer",
2345 GST_DEBUG_PAD_NAME (pad));
2353 * gst_pad_alloc_buffer:
2354 * @pad: a source #GstPad
2355 * @offset: the offset of the new buffer in the stream
2356 * @size: the size of the new buffer
2357 * @caps: the caps of the new buffer
2358 * @buf: a newly allocated buffer
2360 * Allocates a new, empty buffer optimized to push to pad @pad. This
2361 * function only works if @pad is a source pad and has a peer.
2363 * You need to check the caps of the buffer after performing this
2364 * function and renegotiate to the format if needed.
2366 * A new, empty #GstBuffer will be put in the @buf argument.
2368 * Returns: a result code indicating success of the operation. Any
2369 * result code other than GST_FLOW_OK is an error and @buf should
2371 * An error can occur if the pad is not connected or when the downstream
2372 * peer elements cannot provide an acceptable buffer.
2377 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
2382 GstPadBufferAllocFunction bufferallocfunc;
2383 gboolean caps_changed;
2385 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2386 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2387 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2390 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2391 handle_pad_block (pad);
2393 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2396 gst_object_ref (peer);
2399 if (G_LIKELY ((bufferallocfunc = peer->bufferallocfunc) == NULL))
2403 /* when the peer is flushing we cannot give a buffer */
2404 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (peer)))
2407 if (offset == GST_BUFFER_OFFSET_NONE) {
2408 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2409 "calling bufferallocfunc &%s (@%p) of peer pad %s:%s for size %d offset NONE",
2410 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2411 &bufferallocfunc, GST_DEBUG_PAD_NAME (peer), size);
2413 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2414 "calling bufferallocfunc &%s (@%p) of peer pad %s:%s for size %d offset %"
2415 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2416 &bufferallocfunc, GST_DEBUG_PAD_NAME (peer), size, offset);
2420 ret = bufferallocfunc (peer, offset, size, caps, buf);
2422 if (G_UNLIKELY (ret != GST_FLOW_OK))
2424 if (G_UNLIKELY (*buf == NULL))
2427 /* If the buffer alloc function didn't set up the caps like it should,
2429 if (caps && (GST_BUFFER_CAPS (*buf) == NULL)) {
2430 GST_WARNING ("Buffer allocation function for pad % " GST_PTR_FORMAT
2431 " did not set up caps. Setting", peer);
2433 gst_buffer_set_caps (*buf, caps);
2437 gst_object_unref (peer);
2439 /* FIXME, move capnego this into a base class? */
2440 caps = GST_BUFFER_CAPS (*buf);
2441 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2442 /* we got a new datatype on the pad, see if it can handle it */
2443 if (G_UNLIKELY (caps_changed)) {
2444 GST_DEBUG ("caps changed to %" GST_PTR_FORMAT, caps);
2445 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps)))
2446 goto not_negotiated;
2452 /* pad has no peer */
2453 GST_CAT_DEBUG (GST_CAT_PADS,
2454 "%s:%s called bufferallocfunc but had no peer",
2455 GST_DEBUG_PAD_NAME (pad));
2457 return GST_FLOW_NOT_LINKED;
2461 /* peer was flushing */
2463 gst_object_unref (peer);
2464 GST_CAT_DEBUG (GST_CAT_PADS,
2465 "%s:%s called bufferallocfunc but peer was flushing",
2466 GST_DEBUG_PAD_NAME (pad));
2467 return GST_FLOW_WRONG_STATE;
2469 /* fallback case, allocate a buffer of our own, add pad caps. */
2472 GST_CAT_DEBUG (GST_CAT_PADS,
2473 "%s:%s fallback buffer alloc", GST_DEBUG_PAD_NAME (pad));
2474 *buf = gst_buffer_new_and_alloc (size);
2475 GST_BUFFER_OFFSET (*buf) = offset;
2476 gst_buffer_set_caps (*buf, caps);
2484 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2485 "alloc function retured unacceptable buffer");
2486 return GST_FLOW_NOT_NEGOTIATED;
2490 gst_object_unref (peer);
2491 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2492 "alloc function retured error %s", gst_flow_get_name (ret));
2498 * gst_pad_get_internal_links_default:
2499 * @pad: the #GstPad to get the internal links of.
2501 * Gets a list of pads to which the given pad is linked to
2502 * inside of the parent element.
2503 * This is the default handler, and thus returns a list of all of the
2504 * pads inside the parent element with opposite direction.
2505 * The caller must free this list after use.
2507 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
2512 gst_pad_get_internal_links_default (GstPad * pad)
2517 GstPadDirection direction;
2519 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2521 direction = pad->direction;
2523 parent = GST_PAD_PARENT (pad);
2527 parent_pads = parent->pads;
2529 while (parent_pads) {
2530 GstPad *parent_pad = GST_PAD_CAST (parent_pads->data);
2532 if (parent_pad->direction != direction) {
2533 res = g_list_prepend (res, parent_pad);
2536 parent_pads = g_list_next (parent_pads);
2543 * gst_pad_get_internal_links:
2544 * @pad: the #GstPad to get the internal links of.
2546 * Gets a list of pads to which the given pad is linked to
2547 * inside of the parent element.
2548 * The caller must free this list after use.
2550 * Returns: a newly allocated #GList of pads.
2555 gst_pad_get_internal_links (GstPad * pad)
2559 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2561 if (GST_PAD_INTLINKFUNC (pad))
2562 res = GST_PAD_INTLINKFUNC (pad) (pad);
2569 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
2574 GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
2577 result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
2579 orig = pads = gst_pad_get_internal_links (pad);
2582 GstPad *eventpad = GST_PAD_CAST (pads->data);
2584 pads = g_list_next (pads);
2586 /* for all of the internally-linked pads that are actually linked */
2587 if (GST_PAD_IS_LINKED (eventpad)) {
2588 if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
2589 /* for each pad we send to, we should ref the event; it's up
2590 * to downstream to unref again when handled. */
2591 GST_LOG_OBJECT (pad, "Reffing and sending event %p to %s:%s", event,
2592 GST_DEBUG_PAD_NAME (eventpad));
2593 gst_event_ref (event);
2594 gst_pad_push_event (eventpad, event);
2596 /* we only send the event on one pad, multi-sinkpad elements
2597 * should implement a handler */
2598 GST_LOG_OBJECT (pad, "sending event %p to one sink pad %s:%s", event,
2599 GST_DEBUG_PAD_NAME (eventpad));
2600 result = gst_pad_push_event (eventpad, event);
2605 /* we handled the incoming event so we unref once */
2606 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
2607 gst_event_unref (event);
2616 * gst_pad_event_default:
2617 * @pad: a #GstPad to call the default event handler on.
2618 * @event: the #GstEvent to handle.
2620 * Invokes the default event handler for the given pad. End-of-stream and
2621 * discontinuity events are handled specially, and then the event is sent to all
2622 * pads internally linked to @pad. Note that if there are many possible sink
2623 * pads that are internally linked to @pad, only one will be sent an event.
2624 * Multi-sinkpad elements should implement custom event handlers.
2626 * Returns: TRUE if the event was sent succesfully.
2629 gst_pad_event_default (GstPad * pad, GstEvent * event)
2631 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2632 g_return_val_if_fail (event != NULL, FALSE);
2634 switch (GST_EVENT_TYPE (event)) {
2637 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
2638 gst_pad_pause_task (pad);
2644 return gst_pad_event_default_dispatch (pad, event);
2648 * gst_pad_dispatcher:
2649 * @pad: a #GstPad to dispatch.
2650 * @dispatch: the #GstDispatcherFunction to call.
2651 * @data: gpointer user data passed to the dispatcher function.
2653 * Invokes the given dispatcher function on all pads that are
2654 * internally linked to the given pad.
2655 * The GstPadDispatcherFunction should return TRUE when no further pads
2656 * need to be processed.
2658 * Returns: TRUE if one of the dispatcher functions returned TRUE.
2661 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
2664 gboolean res = FALSE;
2665 GList *int_pads, *orig;
2667 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2668 g_return_val_if_fail (dispatch != NULL, FALSE);
2670 orig = int_pads = gst_pad_get_internal_links (pad);
2673 GstPad *int_pad = GST_PAD_CAST (int_pads->data);
2674 GstPad *int_peer = GST_PAD_PEER (int_pad);
2677 res = dispatch (int_peer, data);
2681 int_pads = g_list_next (int_pads);
2691 * @pad: a #GstPad to invoke the default query on.
2692 * @query: the #GstQuery to perform.
2694 * Dispatches a query to a pad. The query should have been allocated by the
2695 * caller via one of the type-specific allocation functions in gstquery.h. The
2696 * element is responsible for filling the query with an appropriate response,
2697 * which should then be parsed with a type-specific query parsing function.
2699 * Again, the caller is responsible for both the allocation and deallocation of
2700 * the query structure.
2702 * Returns: TRUE if the query could be performed.
2705 gst_pad_query (GstPad * pad, GstQuery * query)
2707 GstPadQueryFunction func;
2709 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2710 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2712 GST_DEBUG ("sending query %p to pad %s:%s", query, GST_DEBUG_PAD_NAME (pad));
2714 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
2717 return func (pad, query);
2721 GST_DEBUG ("pad had no query function");
2727 gst_pad_query_default (GstPad * pad, GstQuery * query)
2729 switch (GST_QUERY_TYPE (query)) {
2730 case GST_QUERY_POSITION:
2731 case GST_QUERY_SEEKING:
2732 case GST_QUERY_FORMATS:
2733 case GST_QUERY_LATENCY:
2734 case GST_QUERY_JITTER:
2735 case GST_QUERY_RATE:
2736 case GST_QUERY_CONVERT:
2738 return gst_pad_dispatcher
2739 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
2743 #ifndef GST_DISABLE_LOADSAVE
2744 /* FIXME: why isn't this on a GstElement ? */
2746 * gst_pad_load_and_link:
2747 * @self: an #xmlNodePtr to read the description from.
2748 * @parent: the #GstObject element that owns the pad.
2750 * Reads the pad definition from the XML node and links the given pad
2751 * in the element to a pad of an element up in the hierarchy.
2754 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
2756 xmlNodePtr field = self->xmlChildrenNode;
2757 GstPad *pad = NULL, *targetpad;
2761 GstObject *grandparent;
2765 if (!strcmp ((char *) field->name, "name")) {
2766 name = (gchar *) xmlNodeGetContent (field);
2767 pad = gst_element_get_pad (GST_ELEMENT (parent), name);
2769 } else if (!strcmp ((char *) field->name, "peer")) {
2770 peer = (gchar *) xmlNodeGetContent (field);
2772 field = field->next;
2774 g_return_if_fail (pad != NULL);
2779 split = g_strsplit (peer, ".", 2);
2781 if (split[0] == NULL || split[1] == NULL) {
2782 GST_CAT_DEBUG (GST_CAT_XML,
2783 "Could not parse peer '%s' for pad %s:%s, leaving unlinked",
2784 peer, GST_DEBUG_PAD_NAME (pad));
2791 g_return_if_fail (split[0] != NULL);
2792 g_return_if_fail (split[1] != NULL);
2794 grandparent = gst_object_get_parent (parent);
2796 if (grandparent && GST_IS_BIN (grandparent)) {
2797 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
2804 targetpad = gst_element_get_pad (target, split[1]);
2806 if (targetpad == NULL)
2809 gst_pad_link (pad, targetpad);
2816 * gst_pad_save_thyself:
2817 * @pad: a #GstPad to save.
2818 * @parent: the parent #xmlNodePtr to save the description in.
2820 * Saves the pad into an xml representation.
2822 * Returns: the #xmlNodePtr representation of the pad.
2825 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
2830 g_return_val_if_fail (GST_IS_PAD (object), NULL);
2832 pad = GST_PAD (object);
2834 xmlNewChild (parent, NULL, (xmlChar *) "name",
2835 (xmlChar *) GST_PAD_NAME (pad));
2836 if (GST_PAD_PEER (pad) != NULL) {
2839 peer = GST_PAD_PEER (pad);
2840 /* first check to see if the peer's parent's parent is the same */
2841 /* we just save it off */
2842 content = g_strdup_printf ("%s.%s",
2843 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
2844 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
2847 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
2854 * gst_ghost_pad_save_thyself:
2855 * @pad: a ghost #GstPad to save.
2856 * @parent: the parent #xmlNodePtr to save the description in.
2858 * Saves the ghost pad into an xml representation.
2860 * Returns: the #xmlNodePtr representation of the pad.
2863 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
2867 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
2869 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
2870 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
2871 xmlNewChild (self, NULL, (xmlChar *) "parent",
2872 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
2874 /* FIXME FIXME FIXME! */
2879 #endif /* GST_DISABLE_LOADSAVE */
2882 * should be called with pad lock held
2887 handle_pad_block (GstPad * pad)
2889 GstPadBlockCallback callback;
2892 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2893 "signal block taken on pad %s:%s", GST_DEBUG_PAD_NAME (pad));
2895 /* need to grab extra ref for the callbacks */
2896 gst_object_ref (pad);
2898 callback = pad->block_callback;
2900 user_data = pad->block_data;
2902 callback (pad, TRUE, user_data);
2905 GST_PAD_BLOCK_SIGNAL (pad);
2908 while (GST_PAD_IS_BLOCKED (pad))
2909 GST_PAD_BLOCK_WAIT (pad);
2911 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
2913 callback = pad->block_callback;
2915 user_data = pad->block_data;
2917 callback (pad, FALSE, user_data);
2920 GST_PAD_BLOCK_SIGNAL (pad);
2923 gst_object_unref (pad);
2926 /**********************************************************************
2927 * Data passing functions
2931 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
2934 GValue args[2] = { {0}, {0} };
2939 g_value_init (&ret, G_TYPE_BOOLEAN);
2940 g_value_set_boolean (&ret, TRUE);
2941 g_value_init (&args[0], GST_TYPE_PAD);
2942 g_value_set_object (&args[0], pad);
2943 g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
2944 gst_value_set_mini_object (&args[1], obj);
2946 if (GST_IS_EVENT (obj))
2947 detail = event_quark;
2949 detail = buffer_quark;
2952 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
2953 res = g_value_get_boolean (&ret);
2956 g_value_unset (&ret);
2957 g_value_unset (&args[0]);
2958 g_value_unset (&args[1]);
2965 * @pad: a sink #GstPad.
2966 * @buffer: the #GstBuffer to send.
2968 * Chain a buffer to @pad.
2970 * Returns: a #GstFlowReturn from the pad.
2975 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
2978 gboolean caps_changed;
2979 GstPadChainFunction chainfunc;
2981 gboolean emit_signal;
2983 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2984 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
2986 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
2987 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
2989 GST_STREAM_LOCK (pad);
2992 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2995 caps = GST_BUFFER_CAPS (buffer);
2996 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2998 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3001 /* see if the signal should be emited, we emit before caps nego as
3002 * we might drop the buffer and do capsnego for nothing. */
3003 if (G_UNLIKELY (emit_signal)) {
3004 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3008 /* we got a new datatype on the pad, see if it can handle it */
3009 if (G_UNLIKELY (caps_changed)) {
3010 GST_DEBUG ("caps changed to %" GST_PTR_FORMAT, caps);
3011 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
3012 goto not_negotiated;
3015 /* NOTE: we read the chainfunc unlocked.
3016 * we cannot hold the lock for the pad so we might send
3017 * the data to the wrong function. This is not really a
3018 * problem since functions are assigned at creation time
3019 * and don't change that often... */
3020 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
3023 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3024 "calling chainfunction &%s of pad %s:%s",
3025 GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_DEBUG_PAD_NAME (pad));
3027 ret = chainfunc (pad, buffer);
3029 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3030 "called chainfunction &%s of pad %s:%s, returned %s",
3031 GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_DEBUG_PAD_NAME (pad),
3032 gst_flow_get_name (ret));
3034 GST_STREAM_UNLOCK (pad);
3041 gst_buffer_unref (buffer);
3042 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3043 "pushing, but pad was flushing");
3045 GST_STREAM_UNLOCK (pad);
3046 return GST_FLOW_WRONG_STATE;
3050 gst_buffer_unref (buffer);
3051 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3052 GST_STREAM_UNLOCK (pad);
3057 gst_buffer_unref (buffer);
3058 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3059 "pushing buffer but pad did not accept");
3060 GST_STREAM_UNLOCK (pad);
3061 return GST_FLOW_NOT_NEGOTIATED;
3065 gst_buffer_unref (buffer);
3066 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3067 "pushing, but not chainhandler");
3068 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3069 ("push on pad %s:%s but it has no chainfunction",
3070 GST_DEBUG_PAD_NAME (pad)));
3071 GST_STREAM_UNLOCK (pad);
3072 return GST_FLOW_ERROR;
3078 * @pad: a source #GstPad.
3079 * @buffer: the #GstBuffer to push.
3081 * Pushes a buffer to the peer of @pad.
3082 * buffer probes will be triggered before the buffer gets pushed.
3084 * Returns: a #GstFlowReturn from the peer pad.
3089 gst_pad_push (GstPad * pad, GstBuffer * buffer)
3093 gboolean emit_signal;
3094 gboolean signal_ret = TRUE;
3096 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3097 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3098 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3099 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3103 /* FIXME: this check can go away; pad_set_blocked could be implemented with
3104 * probes completely */
3105 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3106 handle_pad_block (pad);
3108 /* we emit signals on the pad arg, the peer will have a chance to
3109 * emit in the _chain() function */
3110 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3113 if (G_UNLIKELY (emit_signal)) {
3114 signal_ret = gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer));
3117 /* if the signal handler returned FALSE, it means we should just drop the
3119 if (signal_ret == FALSE) {
3120 gst_buffer_unref (buffer);
3121 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3127 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3129 gst_object_ref (peer);
3132 ret = gst_pad_chain (peer, buffer);
3134 gst_object_unref (peer);
3138 /* ERROR recovery here */
3141 gst_buffer_unref (buffer);
3142 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3143 "pushing, but it was not linked");
3145 return GST_FLOW_NOT_LINKED;
3150 * gst_pad_check_pull_range:
3151 * @pad: a sink #GstPad.
3153 * Checks if a #gst_pad_pull_range() can be performed on the peer
3154 * source pad. This function is used by plugins that want to check
3155 * if they can use random access on the peer source pad.
3157 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
3158 * if it needs to perform some logic to determine if pull_range is
3161 * Returns: a gboolean with the result.
3166 gst_pad_check_pull_range (GstPad * pad)
3170 GstPadCheckGetRangeFunction checkgetrangefunc;
3172 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3175 if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
3176 goto wrong_direction;
3178 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3181 gst_object_ref (peer);
3184 /* see note in above function */
3185 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
3186 /* FIXME, kindoff ghetto */
3187 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
3189 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3190 "calling checkgetrangefunc %s of peer pad %s:%s",
3191 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
3193 ret = checkgetrangefunc (peer);
3196 gst_object_unref (peer);
3200 /* ERROR recovery here */
3208 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3209 "checking pull range, but it was not linked");
3216 * gst_pad_get_range:
3217 * @pad: a src #GstPad.
3218 * @offset: The start offset of the buffer
3219 * @size: The length of the buffer
3220 * @buffer: a pointer to hold the #GstBuffer.
3222 * Calls the getrange function of @pad.
3224 * Returns: a #GstFlowReturn from the pad.
3229 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
3230 GstBuffer ** buffer)
3233 GstPadGetRangeFunction getrangefunc;
3234 gboolean emit_signal;
3236 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3237 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3238 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3240 GST_STREAM_LOCK (pad);
3243 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3246 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3249 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
3252 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3253 "calling getrangefunc %s of peer pad %s:%s, offset %"
3254 G_GUINT64_FORMAT ", size %u",
3255 GST_DEBUG_FUNCPTR_NAME (getrangefunc), GST_DEBUG_PAD_NAME (pad),
3258 ret = getrangefunc (pad, offset, size, buffer);
3260 /* can only fire the signal if we have a valid buffer */
3261 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3262 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3266 GST_STREAM_UNLOCK (pad);
3273 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3274 "pulling range, but pad was flushing");
3276 GST_STREAM_UNLOCK (pad);
3277 return GST_FLOW_WRONG_STATE;
3281 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3282 ("pullrange on pad %s:%s but it has no getrangefunction",
3283 GST_DEBUG_PAD_NAME (pad)));
3284 GST_STREAM_UNLOCK (pad);
3285 return GST_FLOW_ERROR;
3289 GST_DEBUG ("Dropping data after FALSE probe return");
3290 GST_STREAM_UNLOCK (pad);
3291 gst_buffer_unref (*buffer);
3293 return GST_FLOW_UNEXPECTED;
3299 * gst_pad_pull_range:
3300 * @pad: a sink #GstPad.
3301 * @offset: The start offset of the buffer
3302 * @size: The length of the buffer
3303 * @buffer: a pointer to hold the #GstBuffer.
3305 * Pulls a buffer from the peer pad. @pad must be a linked
3308 * Returns: a #GstFlowReturn from the peer pad.
3313 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
3314 GstBuffer ** buffer)
3318 gboolean emit_signal;
3320 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3321 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3323 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3327 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3328 handle_pad_block (pad);
3330 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3333 /* signal emision for the pad, peer has chance to emit when
3334 * we call _get_range() */
3335 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3337 gst_object_ref (peer);
3340 ret = gst_pad_get_range (peer, offset, size, buffer);
3342 gst_object_unref (peer);
3344 /* can only fire the signal if we have a valid buffer */
3345 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3346 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3351 /* ERROR recovery here */
3354 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3355 "pulling range, but it was not linked");
3357 return GST_FLOW_NOT_LINKED;
3361 GST_DEBUG ("Dropping data after FALSE probe return");
3362 gst_buffer_unref (*buffer);
3364 return GST_FLOW_UNEXPECTED;
3369 * gst_pad_push_event:
3370 * @pad: a #GstPad to push the event to.
3371 * @event: the #GstEvent to send to the pad.
3373 * Sends the event to the peer of the given pad. This function is
3374 * mainly used by elements to send events to their peer
3377 * Returns: TRUE if the event was handled.
3382 gst_pad_push_event (GstPad * pad, GstEvent * event)
3386 gboolean emit_signal;
3387 gboolean signal_ret = TRUE;
3389 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3390 g_return_val_if_fail (event != NULL, FALSE);
3392 emit_signal = GST_PAD_DO_EVENT_SIGNALS (pad) > 0;
3394 if (G_UNLIKELY (emit_signal)) {
3395 signal_ret = gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event));
3398 if (signal_ret == FALSE) {
3399 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
3400 gst_event_unref (event);
3405 peerpad = GST_PAD_PEER (pad);
3406 if (peerpad == NULL)
3409 gst_object_ref (peerpad);
3412 result = gst_pad_send_event (peerpad, event);
3414 gst_object_unref (peerpad);
3418 /* ERROR handling */
3421 gst_event_unref (event);
3428 * gst_pad_send_event:
3429 * @pad: a #GstPad to send the event to.
3430 * @event: the #GstEvent to send to the pad.
3432 * Sends the event to the pad. This function can be used
3433 * by applications to send events in the pipeline.
3435 * Returns: TRUE if the event was handled.
3438 gst_pad_send_event (GstPad * pad, GstEvent * event)
3440 gboolean result = FALSE;
3441 GstPadEventFunction eventfunc;
3442 gboolean emit_signal;
3444 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3445 g_return_val_if_fail (event != NULL, FALSE);
3449 if (GST_PAD_IS_SINK (pad) && !GST_EVENT_IS_DOWNSTREAM (event))
3450 goto wrong_direction;
3451 if (GST_PAD_IS_SRC (pad) && !GST_EVENT_IS_UPSTREAM (event))
3452 goto wrong_direction;
3454 if (GST_EVENT_SRC (event) == NULL)
3455 GST_EVENT_SRC (event) = gst_object_ref (pad);
3457 switch (GST_EVENT_TYPE (event)) {
3458 case GST_EVENT_FLUSH_START:
3459 GST_CAT_DEBUG (GST_CAT_EVENT,
3460 "have event type %d (FLUSH_START) on pad %s:%s",
3461 GST_EVENT_TYPE (event), GST_DEBUG_PAD_NAME (pad));
3463 /* can't even accept a flush begin event when flushing */
3464 if (GST_PAD_IS_FLUSHING (pad))
3466 GST_PAD_SET_FLUSHING (pad);
3467 GST_CAT_DEBUG (GST_CAT_EVENT, "set flush flag");
3469 case GST_EVENT_FLUSH_STOP:
3470 GST_PAD_UNSET_FLUSHING (pad);
3471 GST_CAT_DEBUG (GST_CAT_EVENT, "cleared flush flag");
3474 GST_CAT_DEBUG (GST_CAT_EVENT, "have event type %d on pad %s:%s",
3475 GST_EVENT_TYPE (event), GST_DEBUG_PAD_NAME (pad));
3477 if (GST_PAD_IS_FLUSHING (pad))
3482 if ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL)
3485 emit_signal = GST_PAD_DO_EVENT_SIGNALS (pad) > 0;
3487 gst_object_ref (pad);
3490 if (G_UNLIKELY (emit_signal)) {
3491 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3495 result = eventfunc (GST_PAD_CAST (pad), event);
3497 gst_object_unref (pad);
3501 /* ERROR handling */
3504 g_warning ("pad %s:%s sending event in wrong direction",
3505 GST_DEBUG_PAD_NAME (pad));
3507 gst_event_unref (event);
3512 g_warning ("pad %s:%s has no event handler, file a bug.",
3513 GST_DEBUG_PAD_NAME (pad));
3515 gst_event_unref (event);
3521 GST_CAT_DEBUG (GST_CAT_EVENT, "Received event on flushing pad. Discarding");
3522 gst_event_unref (event);
3527 GST_DEBUG ("Dropping event after FALSE probe return");
3528 gst_object_unref (pad);
3529 gst_event_unref (event);
3535 * gst_pad_set_element_private:
3536 * @pad: the #GstPad to set the private data of.
3537 * @priv: The private data to attach to the pad.
3539 * Set the given private data gpointer on the pad.
3540 * This function can only be used by the element that owns the pad.
3543 gst_pad_set_element_private (GstPad * pad, gpointer priv)
3545 pad->element_private = priv;
3549 * gst_pad_get_element_private:
3550 * @pad: the #GstPad to get the private data of.
3552 * Gets the private data of a pad.
3554 * Returns: a #gpointer to the private data.
3557 gst_pad_get_element_private (GstPad * pad)
3559 return pad->element_private;
3563 * gst_pad_start_task:
3564 * @pad: the #GstPad to start the task of
3565 * @func: the task function to call
3566 * @data: data passed to the task function
3568 * Starts a task that repeadedly calls @func with @data. This function
3569 * is nostly used in the pad activation function to start the
3570 * dataflow. This function will automatically acauire the STREAM_LOCK of
3571 * the pad before calling @func.
3573 * Returns: a TRUE if the task could be started.
3576 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
3580 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3581 g_return_val_if_fail (func != NULL, FALSE);
3584 task = GST_PAD_TASK (pad);
3586 task = gst_task_create (func, data);
3587 gst_task_set_lock (task, GST_STREAM_GET_LOCK (pad));
3588 GST_PAD_TASK (pad) = task;
3590 gst_task_start (task);
3597 * gst_pad_pause_task:
3598 * @pad: the #GstPad to pause the task of
3600 * Pause the task of @pad. This function will also make sure that the
3601 * function executed by the task will effectively stop.
3603 * Returns: a TRUE if the task could be paused or FALSE when the pad
3607 gst_pad_pause_task (GstPad * pad)
3611 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3614 task = GST_PAD_TASK (pad);
3617 gst_task_pause (task);
3620 GST_STREAM_LOCK (pad);
3621 GST_STREAM_UNLOCK (pad);
3633 * gst_pad_stop_task:
3634 * @pad: the #GstPad to stop the task of
3636 * Stop the task of @pad. This function will also make sure that the
3637 * function executed by the task will effectively stop if not called
3638 * from the GstTaskFunction.
3640 * This function will deadlock if called from the GstTaskFunction of
3641 * the task. Use #gst_task_pause() instead.
3643 * Returns: a TRUE if the task could be stopped or FALSE when the pad
3647 gst_pad_stop_task (GstPad * pad)
3651 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3654 task = GST_PAD_TASK (pad);
3657 GST_PAD_TASK (pad) = NULL;
3658 gst_task_stop (task);
3661 GST_STREAM_LOCK (pad);
3662 GST_STREAM_UNLOCK (pad);
3664 gst_task_join (task);
3666 gst_object_unref (task);