2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
5 * gstpad.c: Pads for linking elements together
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * @short_description: Object contained by elements that allows links to
26 * @see_also: #GstPadTemplate, #GstElement, #GstEvent
28 * A #GstElement is linked to other elements via "pads", which are extremely
29 * light-weight generic link points.
30 * After two pads are retrieved from an element with gst_element_get_pad(),
31 * the pads can be link with gst_pad_link(). (For quick links,
32 * you can also use gst_element_link(), which will make the obvious
33 * link for you if it's straightforward.)
35 * Pads are typically created from a #GstPadTemplate with
36 * gst_pad_new_from_template().
38 * Pads have #GstCaps attached to it to describe the media type they are
39 * capable of dealing with. gst_pad_get_caps() and gst_pad_set_caps() are
40 * used to manipulate the caps of the pads.
41 * Pads created from a pad template cannot set capabilities that are
42 * incompatible with the pad template capabilities.
44 * Pads without pad templates can be created with gst_pad_new(),
45 * which takes a direction and a name as an argument. If the name is NULL,
46 * then a guaranteed unique name will be assigned to it.
48 * gst_pad_get_parent() will retrieve the #GstElement that owns the pad.
50 * A #GstElement creating a pad will typically use the various
51 * gst_pad_set_*_function() calls to register callbacks for various events
54 * GstElements will use gst_pad_push() and gst_pad_pull_range() to push out
55 * or pull in a buffer.
57 * To send a #GstEvent on a pad, use gst_pad_send_event() and
58 * gst_pad_push_event().
60 * Last reviewed on 2006-07-06 (0.10.9)
63 #include "gst_private.h"
66 #include "gstpadtemplate.h"
67 #include "gstenumtypes.h"
68 #include "gstmarshal.h"
73 #include "glib-compat-private.h"
75 GST_DEBUG_CATEGORY_STATIC (debug_dataflow);
76 #define GST_CAT_DEFAULT GST_CAT_PADS
78 /* Pad signals and args */
98 static void gst_pad_class_init (GstPadClass * klass);
99 static void gst_pad_init (GstPad * pad);
100 static void gst_pad_dispose (GObject * object);
101 static void gst_pad_finalize (GObject * object);
102 static void gst_pad_set_property (GObject * object, guint prop_id,
103 const GValue * value, GParamSpec * pspec);
104 static void gst_pad_get_property (GObject * object, guint prop_id,
105 GValue * value, GParamSpec * pspec);
107 static GstFlowReturn handle_pad_block (GstPad * pad);
108 static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
109 static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
110 static gboolean gst_pad_activate_default (GstPad * pad);
111 static gboolean gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps);
113 #ifndef GST_DISABLE_LOADSAVE
114 static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
117 static GstObjectClass *parent_class = NULL;
118 static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
120 /* quarks for probe signals */
121 static GQuark buffer_quark;
122 static GQuark event_quark;
131 static GstFlowQuarks flow_quarks[] = {
132 {GST_FLOW_CUSTOM_SUCCESS, "custom-success", 0},
133 {GST_FLOW_RESEND, "resend", 0},
134 {GST_FLOW_OK, "ok", 0},
135 {GST_FLOW_NOT_LINKED, "not-linked", 0},
136 {GST_FLOW_WRONG_STATE, "wrong-state", 0},
137 {GST_FLOW_UNEXPECTED, "unexpected", 0},
138 {GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
139 {GST_FLOW_ERROR, "error", 0},
140 {GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
141 {GST_FLOW_CUSTOM_ERROR, "custom-error", 0},
148 * @ret: a #GstFlowReturn to get the name of.
150 * Gets a string representing the given flow return.
152 * Returns: a static string with the name of the flow return.
154 G_CONST_RETURN gchar *
155 gst_flow_get_name (GstFlowReturn ret)
159 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
161 for (i = 0; flow_quarks[i].name; i++) {
162 if (ret == flow_quarks[i].ret)
163 return flow_quarks[i].name;
170 * @ret: a #GstFlowReturn to get the quark of.
172 * Get the unique quark for the given GstFlowReturn.
174 * Returns: the quark associated with the flow return or 0 if an
175 * invalid return was specified.
178 gst_flow_to_quark (GstFlowReturn ret)
182 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
184 for (i = 0; flow_quarks[i].name; i++) {
185 if (ret == flow_quarks[i].ret)
186 return flow_quarks[i].quark;
192 gst_pad_get_type (void)
194 static GType gst_pad_type = 0;
196 if (G_UNLIKELY (gst_pad_type == 0)) {
197 static const GTypeInfo pad_info = {
198 sizeof (GstPadClass), NULL, NULL,
199 (GClassInitFunc) gst_pad_class_init, NULL, NULL,
202 (GInstanceInitFunc) gst_pad_init, NULL
206 gst_pad_type = g_type_register_static (GST_TYPE_OBJECT, "GstPad",
209 buffer_quark = g_quark_from_static_string ("buffer");
210 event_quark = g_quark_from_static_string ("event");
212 for (i = 0; flow_quarks[i].name; i++) {
213 flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name);
216 GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW",
217 GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads");
223 _gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
224 GValue * return_accu, const GValue * handler_return, gpointer dummy)
226 gboolean ret = g_value_get_boolean (handler_return);
228 GST_DEBUG ("accumulated %d", ret);
229 g_value_set_boolean (return_accu, ret);
235 default_have_data (GstPad * pad, GstMiniObject * o)
241 gst_pad_class_init (GstPadClass * klass)
243 GObjectClass *gobject_class;
244 GstObjectClass *gstobject_class;
246 gobject_class = G_OBJECT_CLASS (klass);
247 gstobject_class = GST_OBJECT_CLASS (klass);
249 parent_class = g_type_class_peek_parent (klass);
251 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pad_dispose);
252 gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_pad_finalize);
253 gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pad_set_property);
254 gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pad_get_property);
258 * @pad: the pad that emitted the signal
259 * @peer: the peer pad that has been connected
261 * Signals that a pad has been linked to the peer pad.
263 gst_pad_signals[PAD_LINKED] =
264 g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
265 G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
266 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
269 * @pad: the pad that emitted the signal
270 * @peer: the peer pad that has been disconnected
272 * Signals that a pad has been unlinked from the peer pad.
274 gst_pad_signals[PAD_UNLINKED] =
275 g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
276 G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
277 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
279 * GstPad::request-link:
280 * @pad: the pad that emitted the signal
281 * @peer: the peer pad for which a connection is requested
283 * Signals that a pad connection has been requested.
285 gst_pad_signals[PAD_REQUEST_LINK] =
286 g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
287 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
288 NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
292 * @pad: the pad that emitted the signal
293 * @mini_obj: new data
295 * Signals that new data is available on the pad. This signal is used
296 * internally for implementing pad probes.
297 * See gst_pad_add_*_probe functions.
299 * Returns: %TRUE to keep the data, %FALSE to drop it
301 gst_pad_signals[PAD_HAVE_DATA] =
302 g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
303 G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
304 G_STRUCT_OFFSET (GstPadClass, have_data),
305 _gst_do_pass_data_accumulator,
306 NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
307 GST_TYPE_MINI_OBJECT);
309 g_object_class_install_property (gobject_class, PAD_PROP_CAPS,
310 g_param_spec_boxed ("caps", "Caps", "The capabilities of the pad",
311 GST_TYPE_CAPS, G_PARAM_READABLE));
312 g_object_class_install_property (gobject_class, PAD_PROP_DIRECTION,
313 g_param_spec_enum ("direction", "Direction", "The direction of the pad",
314 GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
315 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
316 /* FIXME, Make G_PARAM_CONSTRUCT_ONLY when we fix ghostpads. */
317 g_object_class_install_property (gobject_class, PAD_PROP_TEMPLATE,
318 g_param_spec_object ("template", "Template",
319 "The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
322 #ifndef GST_DISABLE_LOADSAVE
323 gstobject_class->save_thyself = GST_DEBUG_FUNCPTR (gst_pad_save_thyself);
325 gstobject_class->path_string_separator = ".";
327 klass->have_data = default_have_data;
331 gst_pad_init (GstPad * pad)
333 GST_PAD_DIRECTION (pad) = GST_PAD_UNKNOWN;
334 GST_PAD_PEER (pad) = NULL;
336 GST_PAD_CHAINFUNC (pad) = NULL;
338 GST_PAD_LINKFUNC (pad) = NULL;
340 GST_PAD_CAPS (pad) = NULL;
341 GST_PAD_GETCAPSFUNC (pad) = NULL;
343 GST_PAD_ACTIVATEFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_activate_default);
344 GST_PAD_EVENTFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_event_default);
345 GST_PAD_QUERYTYPEFUNC (pad) =
346 GST_DEBUG_FUNCPTR (gst_pad_get_query_types_default);
347 GST_PAD_QUERYFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_query_default);
348 GST_PAD_INTLINKFUNC (pad) =
349 GST_DEBUG_FUNCPTR (gst_pad_get_internal_links_default);
350 GST_PAD_ACCEPTCAPSFUNC (pad) = GST_DEBUG_FUNCPTR (gst_pad_acceptcaps_default);
352 pad->do_buffer_signals = 0;
353 pad->do_event_signals = 0;
355 /* FIXME, should be set flushing initially, see #339326 */
356 GST_PAD_UNSET_FLUSHING (pad);
358 pad->preroll_lock = g_mutex_new ();
359 pad->preroll_cond = g_cond_new ();
361 pad->stream_rec_lock = g_new (GStaticRecMutex, 1);
362 g_static_rec_mutex_init (pad->stream_rec_lock);
364 pad->block_cond = g_cond_new ();
368 gst_pad_dispose (GObject * object)
370 GstPad *pad = GST_PAD (object);
372 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pad, "dispose");
374 /* we don't hold a ref to the peer so we can just set the
376 GST_PAD_PEER (pad) = NULL;
379 gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
381 gst_pad_set_pad_template (pad, NULL);
383 G_OBJECT_CLASS (parent_class)->dispose (object);
387 gst_pad_finalize (GObject * object)
389 GstPad *pad = GST_PAD (object);
392 /* in case the task is still around, clean it up */
393 if ((task = GST_PAD_TASK (pad))) {
394 gst_task_join (task);
395 GST_PAD_TASK (pad) = NULL;
396 gst_object_unref (task);
399 if (pad->stream_rec_lock) {
400 g_static_rec_mutex_free (pad->stream_rec_lock);
401 g_free (pad->stream_rec_lock);
402 pad->stream_rec_lock = NULL;
404 if (pad->preroll_lock) {
405 g_mutex_free (pad->preroll_lock);
406 g_cond_free (pad->preroll_cond);
407 pad->preroll_lock = NULL;
408 pad->preroll_cond = NULL;
410 if (pad->block_cond) {
411 g_cond_free (pad->block_cond);
412 pad->block_cond = NULL;
415 G_OBJECT_CLASS (parent_class)->finalize (object);
419 gst_pad_set_property (GObject * object, guint prop_id,
420 const GValue * value, GParamSpec * pspec)
422 g_return_if_fail (GST_IS_PAD (object));
425 case PAD_PROP_DIRECTION:
426 GST_PAD_DIRECTION (object) = g_value_get_enum (value);
428 case PAD_PROP_TEMPLATE:
429 gst_pad_set_pad_template (GST_PAD_CAST (object),
430 (GstPadTemplate *) g_value_get_object (value));
433 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
439 gst_pad_get_property (GObject * object, guint prop_id,
440 GValue * value, GParamSpec * pspec)
442 g_return_if_fail (GST_IS_PAD (object));
446 GST_OBJECT_LOCK (object);
447 g_value_set_boxed (value, GST_PAD_CAPS (object));
448 GST_OBJECT_UNLOCK (object);
450 case PAD_PROP_DIRECTION:
451 g_value_set_enum (value, GST_PAD_DIRECTION (object));
453 case PAD_PROP_TEMPLATE:
454 g_value_set_object (value, GST_PAD_PAD_TEMPLATE (object));
457 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
464 * @name: the name of the new pad.
465 * @direction: the #GstPadDirection of the pad.
467 * Creates a new pad with the given name in the given direction.
468 * If name is NULL, a guaranteed unique name (across all pads)
470 * This function makes a copy of the name so you can safely free the name.
472 * Returns: a new #GstPad, or NULL in case of an error.
477 gst_pad_new (const gchar * name, GstPadDirection direction)
479 return g_object_new (GST_TYPE_PAD,
480 "name", name, "direction", direction, NULL);
484 * gst_pad_new_from_template:
485 * @templ: the pad template to use
486 * @name: the name of the element
488 * Creates a new pad with the given name from the given template.
489 * If name is NULL, a guaranteed unique name (across all pads)
491 * This function makes a copy of the name so you can safely free the name.
493 * Returns: a new #GstPad, or NULL in case of an error.
496 gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
498 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
500 return g_object_new (GST_TYPE_PAD,
501 "name", name, "direction", templ->direction, "template", templ, NULL);
505 * gst_pad_new_from_static_template:
506 * @templ: the #GstStaticPadTemplate to use
507 * @name: the name of the element
509 * Creates a new pad with the given name from the given static template.
510 * If name is NULL, a guaranteed unique name (across all pads)
512 * This function makes a copy of the name so you can safely free the name.
514 * Returns: a new #GstPad, or NULL in case of an error.
517 gst_pad_new_from_static_template (GstStaticPadTemplate * templ,
521 GstPadTemplate *template;
523 template = gst_static_pad_template_get (templ);
524 pad = gst_pad_new_from_template (template, name);
525 gst_object_unref (template);
530 * gst_pad_get_direction:
531 * @pad: a #GstPad to get the direction of.
533 * Gets the direction of the pad. The direction of the pad is
534 * decided at construction time so this function does not take
537 * Returns: the #GstPadDirection of the pad.
542 gst_pad_get_direction (GstPad * pad)
544 GstPadDirection result;
546 /* PAD_UNKNOWN is a little silly but we need some sort of
547 * error return value */
548 g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
550 GST_OBJECT_LOCK (pad);
551 result = GST_PAD_DIRECTION (pad);
552 GST_OBJECT_UNLOCK (pad);
558 gst_pad_activate_default (GstPad * pad)
560 return gst_pad_activate_push (pad, TRUE);
564 pre_activate (GstPad * pad, GstActivateMode new_mode)
567 case GST_ACTIVATE_PUSH:
568 case GST_ACTIVATE_PULL:
569 GST_OBJECT_LOCK (pad);
570 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d, unset flushing",
572 GST_PAD_UNSET_FLUSHING (pad);
573 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
574 GST_OBJECT_UNLOCK (pad);
576 case GST_ACTIVATE_NONE:
577 GST_OBJECT_LOCK (pad);
578 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE NONE, set flushing");
579 GST_PAD_SET_FLUSHING (pad);
580 /* unlock blocked pads so element can resume and stop */
581 GST_PAD_BLOCK_SIGNAL (pad);
582 GST_OBJECT_UNLOCK (pad);
588 post_activate (GstPad * pad, GstActivateMode new_mode)
591 case GST_ACTIVATE_PUSH:
592 case GST_ACTIVATE_PULL:
595 case GST_ACTIVATE_NONE:
596 /* ensures that streaming stops */
597 GST_PAD_STREAM_LOCK (pad);
598 /* while we're at it set activation mode */
599 GST_OBJECT_LOCK (pad);
600 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d", new_mode);
601 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
602 GST_OBJECT_UNLOCK (pad);
603 GST_PAD_STREAM_UNLOCK (pad);
609 * gst_pad_set_active:
610 * @pad: the #GstPad to activate or deactivate.
611 * @active: whether or not the pad should be active.
613 * Activates or deactivates the given pad.
614 * Normally called from within core state change functions.
616 * If @active, makes sure the pad is active. If it is already active, either in
617 * push or pull mode, just return. Otherwise dispatches to the pad's activate
618 * function to perform the actual activation.
620 * If not @active, checks the pad's current mode and calls
621 * gst_pad_activate_push() or gst_pad_activate_pull(), as appropriate, with a
624 * Returns: #TRUE if the operation was successful.
629 gst_pad_set_active (GstPad * pad, gboolean active)
632 gboolean ret = FALSE;
634 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
636 GST_OBJECT_LOCK (pad);
637 old = GST_PAD_ACTIVATE_MODE (pad);
638 GST_OBJECT_UNLOCK (pad);
642 case GST_ACTIVATE_PUSH:
643 case GST_ACTIVATE_PULL:
646 case GST_ACTIVATE_NONE:
647 ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
652 case GST_ACTIVATE_PUSH:
653 ret = gst_pad_activate_push (pad, FALSE);
655 case GST_ACTIVATE_PULL:
656 ret = gst_pad_activate_pull (pad, FALSE);
658 case GST_ACTIVATE_NONE:
665 GST_OBJECT_LOCK (pad);
667 g_critical ("Failed to deactivate pad %s:%s, very bad",
668 GST_DEBUG_PAD_NAME (pad));
670 GST_WARNING ("Failed to activate pad %s:%s", GST_DEBUG_PAD_NAME (pad));
672 GST_OBJECT_UNLOCK (pad);
679 * gst_pad_activate_pull:
680 * @pad: the #GstPad to activate or deactivate.
681 * @active: whether or not the pad should be active.
683 * Activates or deactivates the given pad in pull mode via dispatching to the
684 * pad's activatepullfunc. For use from within pad activation functions only.
685 * When called on sink pads, will first proxy the call to the peer pad, which is
686 * expected to activate its internally linked pads from within its activate_pull
689 * If you don't know what this is, you probably don't want to call it.
691 * Returns: TRUE if the operation was successful.
696 gst_pad_activate_pull (GstPad * pad, gboolean active)
698 GstActivateMode old, new;
701 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
703 GST_OBJECT_LOCK (pad);
704 old = GST_PAD_ACTIVATE_MODE (pad);
705 GST_OBJECT_UNLOCK (pad);
709 case GST_ACTIVATE_PULL:
711 case GST_ACTIVATE_PUSH:
712 /* pad was activate in the wrong direction, deactivate it
713 * and reactivate it in pull mode */
714 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
715 goto deactivate_failed;
716 /* fallthrough, pad is deactivated now. */
717 case GST_ACTIVATE_NONE:
722 case GST_ACTIVATE_NONE:
724 case GST_ACTIVATE_PUSH:
725 /* pad was activated in the other direction, deactivate it
726 * in push mode, this should not happen... */
727 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
728 goto deactivate_failed;
729 /* everything is fine now */
731 case GST_ACTIVATE_PULL:
736 if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
737 if ((peer = gst_pad_get_peer (pad))) {
738 if (G_UNLIKELY (!gst_pad_activate_pull (peer, active)))
740 gst_object_unref (peer);
743 if (G_UNLIKELY (GST_PAD_GETRANGEFUNC (pad) == NULL))
744 goto failure; /* Can't activate pull on a src without a
748 new = active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
749 pre_activate (pad, new);
751 if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
752 if (G_UNLIKELY (!GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active)))
755 /* can happen for sinks of passthrough elements */
758 post_activate (pad, new);
760 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
761 active ? "activated" : "deactivated");
767 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
768 active ? "activated" : "deactivated");
773 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
774 "failed to %s in switch to pull from mode %d",
775 (active ? "activate" : "deactivate"), old);
780 GST_OBJECT_LOCK (peer);
781 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
782 "activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
783 GST_OBJECT_UNLOCK (peer);
784 gst_object_unref (peer);
789 GST_OBJECT_LOCK (pad);
790 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
791 active ? "activate" : "deactivate");
792 GST_PAD_SET_FLUSHING (pad);
793 GST_PAD_ACTIVATE_MODE (pad) = old;
794 GST_OBJECT_UNLOCK (pad);
800 * gst_pad_activate_push:
801 * @pad: the #GstPad to activate or deactivate.
802 * @active: whether the pad should be active or not.
804 * Activates or deactivates the given pad in push mode via dispatching to the
805 * pad's activatepushfunc. For use from within pad activation functions only.
807 * If you don't know what this is, you probably don't want to call it.
809 * Returns: %TRUE if the operation was successful.
814 gst_pad_activate_push (GstPad * pad, gboolean active)
816 GstActivateMode old, new;
818 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
819 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
820 active ? "activated" : "deactivated");
822 GST_OBJECT_LOCK (pad);
823 old = GST_PAD_ACTIVATE_MODE (pad);
824 GST_OBJECT_UNLOCK (pad);
828 case GST_ACTIVATE_PUSH:
830 case GST_ACTIVATE_PULL:
831 /* pad was activate in the wrong direction, deactivate it
832 * an reactivate it in push mode */
833 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
834 goto deactivate_failed;
835 /* fallthrough, pad is deactivated now. */
836 case GST_ACTIVATE_NONE:
841 case GST_ACTIVATE_NONE:
843 case GST_ACTIVATE_PULL:
844 /* pad was activated in the other direction, deactivate it
845 * in pull mode, this should not happen... */
846 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
847 goto deactivate_failed;
848 /* everything is fine now */
850 case GST_ACTIVATE_PUSH:
855 new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
856 pre_activate (pad, new);
858 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
859 if (G_UNLIKELY (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active))) {
863 /* quite ok, element relies on state change func to prepare itself */
866 post_activate (pad, new);
868 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
869 active ? "activated" : "deactivated");
874 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
875 active ? "activated" : "deactivated");
880 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
881 "failed to %s in switch to push from mode %d",
882 (active ? "activate" : "deactivate"), old);
887 GST_OBJECT_LOCK (pad);
888 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
889 active ? "activate" : "deactivate");
890 GST_PAD_SET_FLUSHING (pad);
891 GST_PAD_ACTIVATE_MODE (pad) = old;
892 GST_OBJECT_UNLOCK (pad);
899 * @pad: the #GstPad to query
901 * Query if a pad is active
903 * Returns: TRUE if the pad is active.
908 gst_pad_is_active (GstPad * pad)
910 gboolean result = FALSE;
912 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
914 GST_OBJECT_LOCK (pad);
915 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
916 GST_OBJECT_UNLOCK (pad);
922 * gst_pad_set_blocked_async:
923 * @pad: the #GstPad to block or unblock
924 * @blocked: boolean indicating whether the pad should be blocked or unblocked
925 * @callback: #GstPadBlockCallback that will be called when the
927 * @user_data: user data passed to the callback
929 * Blocks or unblocks the dataflow on a pad. The provided callback
930 * is called when the operation succeeds; this happens right before the next
931 * attempt at pushing a buffer on the pad.
933 * This can take a while as the pad can only become blocked when real dataflow
935 * When the pipeline is stalled, for example in PAUSED, this can
936 * take an indeterminate amount of time.
937 * You can pass NULL as the callback to make this call block. Be careful with
938 * this blocking call as it might not return for reasons stated above.
940 * Returns: TRUE if the pad could be blocked. This function can fail
941 * if wrong parameters were passed or the pad was already in the
947 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
948 GstPadBlockCallback callback, gpointer user_data)
950 gboolean was_blocked = FALSE;
952 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
954 GST_OBJECT_LOCK (pad);
956 was_blocked = GST_PAD_IS_BLOCKED (pad);
958 if (G_UNLIKELY (was_blocked == blocked))
959 goto had_right_state;
962 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
964 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
965 pad->block_callback = callback;
966 pad->block_data = user_data;
968 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
969 GST_PAD_BLOCK_WAIT (pad);
970 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
973 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
975 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
977 pad->block_callback = callback;
978 pad->block_data = user_data;
981 GST_PAD_BLOCK_SIGNAL (pad);
983 GST_PAD_BLOCK_SIGNAL (pad);
984 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
985 GST_PAD_BLOCK_WAIT (pad);
986 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
989 GST_OBJECT_UNLOCK (pad);
995 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
996 "pad was in right state (%d)", was_blocked);
997 GST_OBJECT_UNLOCK (pad);
1004 * gst_pad_set_blocked:
1005 * @pad: the #GstPad to block or unblock
1006 * @blocked: boolean indicating we should block or unblock
1008 * Blocks or unblocks the dataflow on a pad. This function is
1009 * a shortcut for gst_pad_set_blocked_async() with a NULL
1012 * Returns: TRUE if the pad could be blocked. This function can fail
1013 * wrong parameters were passed or the pad was already in the
1019 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
1021 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
1025 * gst_pad_is_blocked:
1026 * @pad: the #GstPad to query
1028 * Checks if the pad is blocked or not. This function returns the
1029 * last requested state of the pad. It is not certain that the pad
1030 * is actually blocking at this point (see gst_pad_is_blocking()).
1032 * Returns: TRUE if the pad is blocked.
1037 gst_pad_is_blocked (GstPad * pad)
1039 gboolean result = FALSE;
1041 g_return_val_if_fail (GST_IS_PAD (pad), result);
1043 GST_OBJECT_LOCK (pad);
1044 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
1045 GST_OBJECT_UNLOCK (pad);
1051 * gst_pad_is_blocking:
1052 * @pad: the #GstPad to query
1054 * Checks if the pad is blocking or not. This is a guaranteed state
1055 * of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
1057 * Returns: TRUE if the pad is blocking.
1064 gst_pad_is_blocking (GstPad * pad)
1066 gboolean result = FALSE;
1068 g_return_val_if_fail (GST_IS_PAD (pad), result);
1070 GST_OBJECT_LOCK (pad);
1072 /* the blocking flag is only valid if the pad is not flushing */
1074 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKING) &&
1075 !GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLUSHING);
1076 GST_OBJECT_UNLOCK (pad);
1082 * gst_pad_set_activate_function:
1084 * @activate: the #GstPadActivateFunction to set.
1086 * Sets the given activate function for @pad. The activate function will
1087 * dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
1088 * the actual activation. Only makes sense to set on sink pads.
1090 * Call this function if your sink pad can start a pull-based task.
1093 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
1095 g_return_if_fail (GST_IS_PAD (pad));
1097 GST_PAD_ACTIVATEFUNC (pad) = activate;
1098 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
1099 GST_DEBUG_FUNCPTR_NAME (activate));
1103 * gst_pad_set_activatepull_function:
1105 * @activatepull: the #GstPadActivateModeFunction to set.
1107 * Sets the given activate_pull function for the pad. An activate_pull function
1108 * prepares the element and any upstream connections for pulling. See XXX
1109 * part-activation.txt for details.
1112 gst_pad_set_activatepull_function (GstPad * pad,
1113 GstPadActivateModeFunction activatepull)
1115 g_return_if_fail (GST_IS_PAD (pad));
1117 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
1118 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
1119 GST_DEBUG_FUNCPTR_NAME (activatepull));
1123 * gst_pad_set_activatepush_function:
1125 * @activatepush: the #GstPadActivateModeFunction to set.
1127 * Sets the given activate_push function for the pad. An activate_push function
1128 * prepares the element for pushing. See XXX part-activation.txt for details.
1131 gst_pad_set_activatepush_function (GstPad * pad,
1132 GstPadActivateModeFunction activatepush)
1134 g_return_if_fail (GST_IS_PAD (pad));
1136 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1137 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
1138 GST_DEBUG_FUNCPTR_NAME (activatepush));
1142 * gst_pad_set_chain_function:
1143 * @pad: a sink #GstPad.
1144 * @chain: the #GstPadChainFunction to set.
1146 * Sets the given chain function for the pad. The chain function is called to
1147 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1150 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1152 g_return_if_fail (GST_IS_PAD (pad));
1153 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
1155 GST_PAD_CHAINFUNC (pad) = chain;
1156 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
1157 GST_DEBUG_FUNCPTR_NAME (chain));
1161 * gst_pad_set_getrange_function:
1162 * @pad: a source #GstPad.
1163 * @get: the #GstPadGetRangeFunction to set.
1165 * Sets the given getrange function for the pad. The getrange function is called to
1166 * produce a new #GstBuffer to start the processing pipeline. see
1167 * #GstPadGetRangeFunction for a description of the getrange function.
1170 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1172 g_return_if_fail (GST_IS_PAD (pad));
1173 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1175 GST_PAD_GETRANGEFUNC (pad) = get;
1177 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
1178 GST_DEBUG_FUNCPTR_NAME (get));
1182 * gst_pad_set_checkgetrange_function:
1183 * @pad: a source #GstPad.
1184 * @check: the #GstPadCheckGetRangeFunction to set.
1186 * Sets the given checkgetrange function for the pad. Implement this function on
1187 * a pad if you dynamically support getrange based scheduling on the pad.
1190 gst_pad_set_checkgetrange_function (GstPad * pad,
1191 GstPadCheckGetRangeFunction check)
1193 g_return_if_fail (GST_IS_PAD (pad));
1194 g_return_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC);
1196 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1198 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
1199 GST_DEBUG_FUNCPTR_NAME (check));
1203 * gst_pad_set_event_function:
1204 * @pad: a source #GstPad.
1205 * @event: the #GstPadEventFunction to set.
1207 * Sets the given event handler for the pad.
1210 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1212 g_return_if_fail (GST_IS_PAD (pad));
1214 GST_PAD_EVENTFUNC (pad) = event;
1216 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
1217 GST_DEBUG_FUNCPTR_NAME (event));
1221 * gst_pad_set_query_function:
1222 * @pad: a #GstPad of either direction.
1223 * @query: the #GstPadQueryFunction to set.
1225 * Set the given query function for the pad.
1228 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1230 g_return_if_fail (GST_IS_PAD (pad));
1232 GST_PAD_QUERYFUNC (pad) = query;
1234 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
1235 GST_DEBUG_FUNCPTR_NAME (query));
1239 * gst_pad_set_query_type_function:
1240 * @pad: a #GstPad of either direction.
1241 * @type_func: the #GstPadQueryTypeFunction to set.
1243 * Set the given query type function for the pad.
1246 gst_pad_set_query_type_function (GstPad * pad,
1247 GstPadQueryTypeFunction type_func)
1249 g_return_if_fail (GST_IS_PAD (pad));
1251 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1253 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
1254 GST_DEBUG_FUNCPTR_NAME (type_func));
1258 * gst_pad_get_query_types:
1261 * Get an array of supported queries that can be performed
1264 * Returns: a zero-terminated array of #GstQueryType.
1266 const GstQueryType *
1267 gst_pad_get_query_types (GstPad * pad)
1269 GstPadQueryTypeFunction func;
1271 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1273 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1285 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1287 *data = gst_pad_get_query_types (pad);
1293 * gst_pad_get_query_types_default:
1296 * Invoke the default dispatcher for the query types on
1299 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1300 * internally-linked pads has a query types function.
1302 const GstQueryType *
1303 gst_pad_get_query_types_default (GstPad * pad)
1305 GstQueryType *result = NULL;
1307 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1309 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1310 gst_pad_get_query_types_dispatcher, &result);
1316 * gst_pad_set_internal_link_function:
1317 * @pad: a #GstPad of either direction.
1318 * @intlink: the #GstPadIntLinkFunction to set.
1320 * Sets the given internal link function for the pad.
1323 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1325 g_return_if_fail (GST_IS_PAD (pad));
1327 GST_PAD_INTLINKFUNC (pad) = intlink;
1328 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
1329 GST_DEBUG_FUNCPTR_NAME (intlink));
1333 * gst_pad_set_link_function:
1335 * @link: the #GstPadLinkFunction to set.
1337 * Sets the given link function for the pad. It will be called when
1338 * the pad is linked with another pad.
1340 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1343 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1344 * cannot be made for some reason.
1346 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1347 * of the peer sink pad, if present.
1350 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1352 g_return_if_fail (GST_IS_PAD (pad));
1354 GST_PAD_LINKFUNC (pad) = link;
1355 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
1356 GST_DEBUG_FUNCPTR_NAME (link));
1360 * gst_pad_set_unlink_function:
1362 * @unlink: the #GstPadUnlinkFunction to set.
1364 * Sets the given unlink function for the pad. It will be called
1365 * when the pad is unlinked.
1368 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1370 g_return_if_fail (GST_IS_PAD (pad));
1372 GST_PAD_UNLINKFUNC (pad) = unlink;
1373 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
1374 GST_DEBUG_FUNCPTR_NAME (unlink));
1378 * gst_pad_set_getcaps_function:
1380 * @getcaps: the #GstPadGetCapsFunction to set.
1382 * Sets the given getcaps function for the pad. @getcaps should return the
1383 * allowable caps for a pad in the context of the element's state, its link to
1384 * other elements, and the devices or files it has opened. These caps must be a
1385 * subset of the pad template caps. In the NULL state with no links, @getcaps
1386 * should ideally return the same caps as the pad template. In rare
1387 * circumstances, an object property can affect the caps returned by @getcaps,
1388 * but this is discouraged.
1390 * You do not need to call this function if @pad's allowed caps are always the
1391 * same as the pad template caps. This can only be true if the padtemplate
1392 * has fixed simple caps.
1394 * For most filters, the caps returned by @getcaps is directly affected by the
1395 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1396 * the srcpad's getcaps function is directly related to the stream data. Again,
1397 * @getcaps should return the most specific caps it reasonably can, since this
1398 * helps with autoplugging.
1400 * Note that the return value from @getcaps is owned by the caller, so the caller
1401 * should unref the caps after usage.
1404 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1406 g_return_if_fail (GST_IS_PAD (pad));
1408 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1409 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
1410 GST_DEBUG_FUNCPTR_NAME (getcaps));
1414 * gst_pad_set_acceptcaps_function:
1416 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1418 * Sets the given acceptcaps function for the pad. The acceptcaps function
1419 * will be called to check if the pad can accept the given caps. Setting the
1420 * acceptcaps function to NULL restores the default behaviour of allowing
1421 * any caps that matches the caps from gst_pad_get_caps.
1424 gst_pad_set_acceptcaps_function (GstPad * pad,
1425 GstPadAcceptCapsFunction acceptcaps)
1427 g_return_if_fail (GST_IS_PAD (pad));
1429 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1430 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
1431 GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1435 * gst_pad_set_fixatecaps_function:
1437 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1439 * Sets the given fixatecaps function for the pad. The fixatecaps function
1440 * will be called whenever the default values for a GstCaps needs to be
1444 gst_pad_set_fixatecaps_function (GstPad * pad,
1445 GstPadFixateCapsFunction fixatecaps)
1447 g_return_if_fail (GST_IS_PAD (pad));
1449 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1450 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
1451 GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1455 * gst_pad_set_setcaps_function:
1457 * @setcaps: the #GstPadSetCapsFunction to set.
1459 * Sets the given setcaps function for the pad. The setcaps function
1460 * will be called whenever a buffer with a new media type is pushed or
1461 * pulled from the pad. The pad/element needs to update its internal
1462 * structures to process the new media type. If this new type is not
1463 * acceptable, the setcaps function should return FALSE.
1466 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1468 g_return_if_fail (GST_IS_PAD (pad));
1470 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1471 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
1472 GST_DEBUG_FUNCPTR_NAME (setcaps));
1476 * gst_pad_set_bufferalloc_function:
1477 * @pad: a sink #GstPad.
1478 * @bufalloc: the #GstPadBufferAllocFunction to set.
1480 * Sets the given bufferalloc function for the pad. Note that the
1481 * bufferalloc function can only be set on sinkpads.
1484 gst_pad_set_bufferalloc_function (GstPad * pad,
1485 GstPadBufferAllocFunction bufalloc)
1487 g_return_if_fail (GST_IS_PAD (pad));
1488 g_return_if_fail (GST_PAD_IS_SINK (pad));
1490 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1491 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
1492 GST_DEBUG_FUNCPTR_NAME (bufalloc));
1497 * @srcpad: the source #GstPad to unlink.
1498 * @sinkpad: the sink #GstPad to unlink.
1500 * Unlinks the source pad from the sink pad. Will emit the "unlinked" signal on
1503 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1504 * the pads were not linked together.
1509 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1511 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1512 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1514 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1515 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1516 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1518 GST_OBJECT_LOCK (srcpad);
1520 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1523 GST_OBJECT_LOCK (sinkpad);
1525 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1528 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1529 goto not_linked_together;
1531 if (GST_PAD_UNLINKFUNC (srcpad)) {
1532 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1534 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1535 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1538 /* first clear peers */
1539 GST_PAD_PEER (srcpad) = NULL;
1540 GST_PAD_PEER (sinkpad) = NULL;
1542 GST_OBJECT_UNLOCK (sinkpad);
1543 GST_OBJECT_UNLOCK (srcpad);
1545 /* fire off a signal to each of the pads telling them
1546 * that they've been unlinked */
1547 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1548 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1550 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1551 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1557 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1558 GST_OBJECT_UNLOCK (srcpad);
1563 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1564 GST_OBJECT_UNLOCK (sinkpad);
1565 GST_OBJECT_UNLOCK (srcpad);
1568 not_linked_together:
1570 /* we do not emit a warning in this case because unlinking cannot
1571 * be made MT safe.*/
1572 GST_OBJECT_UNLOCK (sinkpad);
1573 GST_OBJECT_UNLOCK (srcpad);
1579 * gst_pad_is_linked:
1580 * @pad: pad to check
1582 * Checks if a @pad is linked to another pad or not.
1584 * Returns: TRUE if the pad is linked, FALSE otherwise.
1589 gst_pad_is_linked (GstPad * pad)
1593 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1595 GST_OBJECT_LOCK (pad);
1596 result = (GST_PAD_PEER (pad) != NULL);
1597 GST_OBJECT_UNLOCK (pad);
1602 /* get the caps from both pads and see if the intersection
1605 * This function should be called with the pad LOCK on both
1609 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink)
1615 srccaps = gst_pad_get_caps_unlocked (src);
1616 sinkcaps = gst_pad_get_caps_unlocked (sink);
1618 GST_CAT_DEBUG (GST_CAT_CAPS, "src caps %" GST_PTR_FORMAT, srccaps);
1619 GST_CAT_DEBUG (GST_CAT_CAPS, "sink caps %" GST_PTR_FORMAT, sinkcaps);
1621 /* if we have caps on both pads we can check the intersection. If one
1622 * of the caps is NULL, we return TRUE. */
1623 if (srccaps == NULL || sinkcaps == NULL)
1626 icaps = gst_caps_intersect (srccaps, sinkcaps);
1627 gst_caps_unref (srccaps);
1628 gst_caps_unref (sinkcaps);
1633 GST_CAT_DEBUG (GST_CAT_CAPS,
1634 "intersection caps %p %" GST_PTR_FORMAT, icaps, icaps);
1636 if (gst_caps_is_empty (icaps))
1639 gst_caps_unref (icaps);
1644 /* incompatible cases */
1647 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection gave NULL");
1652 GST_CAT_DEBUG (GST_CAT_CAPS, "intersection is EMPTY");
1653 gst_caps_unref (icaps);
1658 /* check if the grandparents of both pads are the same.
1659 * This check is required so that we don't try to link
1660 * pads from elements in different bins without ghostpads.
1662 * The LOCK should be held on both pads
1665 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1667 GstObject *psrc, *psink;
1668 gboolean res = TRUE;
1670 psrc = GST_OBJECT_PARENT (src);
1671 psink = GST_OBJECT_PARENT (sink);
1673 /* if one of the pads has no parent, we allow the link */
1674 if (psrc && psink) {
1675 /* if the parents are the same, we have a loop */
1676 if (G_UNLIKELY (psrc == psink))
1679 /* if they both have a parent, we check the grandparents */
1680 psrc = gst_object_get_parent (psrc);
1681 psink = gst_object_get_parent (psink);
1683 if (G_UNLIKELY (psrc != psink)) {
1684 /* if they have grandparents but they are not the same */
1685 GST_CAT_DEBUG (GST_CAT_CAPS,
1686 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1687 GST_PTR_FORMAT, psrc, psink);
1691 gst_object_unref (psrc);
1693 gst_object_unref (psink);
1701 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1708 /* FIXME leftover from an attempt at refactoring... */
1709 /* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
1710 * the two pads will be locked in the srcpad, sinkpad order. */
1711 static GstPadLinkReturn
1712 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad)
1714 /* generic checks */
1715 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
1716 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
1718 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1719 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1721 GST_OBJECT_LOCK (srcpad);
1723 if (G_UNLIKELY (GST_PAD_DIRECTION (srcpad) != GST_PAD_SRC))
1726 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1727 goto src_was_linked;
1729 GST_OBJECT_LOCK (sinkpad);
1731 if (G_UNLIKELY (GST_PAD_DIRECTION (sinkpad) != GST_PAD_SINK))
1734 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1735 goto sink_was_linked;
1737 /* check hierarchy, pads can only be linked if the grandparents
1739 if (!gst_pad_link_check_hierarchy (srcpad, sinkpad))
1740 goto wrong_hierarchy;
1742 /* check pad caps for non-empty intersection */
1743 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad))
1746 /* FIXME check pad scheduling for non-empty intersection */
1748 return GST_PAD_LINK_OK;
1752 g_critical ("pad %s is not a source pad", GST_PAD_NAME (srcpad));
1753 GST_OBJECT_UNLOCK (srcpad);
1754 return GST_PAD_LINK_WRONG_DIRECTION;
1758 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
1759 GST_DEBUG_PAD_NAME (srcpad),
1760 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1761 /* we do not emit a warning in this case because unlinking cannot
1762 * be made MT safe.*/
1763 GST_OBJECT_UNLOCK (srcpad);
1764 return GST_PAD_LINK_WAS_LINKED;
1768 g_critical ("pad %s is not a sink pad", GST_PAD_NAME (sinkpad));
1769 GST_OBJECT_UNLOCK (sinkpad);
1770 GST_OBJECT_UNLOCK (srcpad);
1771 return GST_PAD_LINK_WRONG_DIRECTION;
1775 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
1776 GST_DEBUG_PAD_NAME (sinkpad),
1777 GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
1778 /* we do not emit a warning in this case because unlinking cannot
1779 * be made MT safe.*/
1780 GST_OBJECT_UNLOCK (sinkpad);
1781 GST_OBJECT_UNLOCK (srcpad);
1782 return GST_PAD_LINK_WAS_LINKED;
1786 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1787 GST_OBJECT_UNLOCK (sinkpad);
1788 GST_OBJECT_UNLOCK (srcpad);
1789 return GST_PAD_LINK_WRONG_HIERARCHY;
1793 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1794 GST_OBJECT_UNLOCK (sinkpad);
1795 GST_OBJECT_UNLOCK (srcpad);
1796 return GST_PAD_LINK_NOFORMAT;
1802 * @srcpad: the source #GstPad to link.
1803 * @sinkpad: the sink #GstPad to link.
1805 * Links the source pad and the sink pad.
1807 * Returns: A result code indicating if the connection worked or
1813 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
1815 GstPadLinkReturn result;
1817 /* prepare will also lock the two pads */
1818 result = gst_pad_link_prepare (srcpad, sinkpad);
1820 if (result != GST_PAD_LINK_OK)
1821 goto prepare_failed;
1823 /* must set peers before calling the link function */
1824 GST_PAD_PEER (srcpad) = sinkpad;
1825 GST_PAD_PEER (sinkpad) = srcpad;
1827 GST_OBJECT_UNLOCK (sinkpad);
1828 GST_OBJECT_UNLOCK (srcpad);
1830 /* FIXME released the locks here, concurrent thread might link
1831 * something else. */
1832 if (GST_PAD_LINKFUNC (srcpad)) {
1833 /* this one will call the peer link function */
1834 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
1835 } else if (GST_PAD_LINKFUNC (sinkpad)) {
1836 /* if no source link function, we need to call the sink link
1837 * function ourselves. */
1838 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
1840 result = GST_PAD_LINK_OK;
1843 GST_OBJECT_LOCK (srcpad);
1844 GST_OBJECT_LOCK (sinkpad);
1846 if (result == GST_PAD_LINK_OK) {
1847 GST_OBJECT_UNLOCK (sinkpad);
1848 GST_OBJECT_UNLOCK (srcpad);
1850 /* fire off a signal to each of the pads telling them
1851 * that they've been linked */
1852 g_signal_emit (G_OBJECT (srcpad), gst_pad_signals[PAD_LINKED], 0, sinkpad);
1853 g_signal_emit (G_OBJECT (sinkpad), gst_pad_signals[PAD_LINKED], 0, srcpad);
1855 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
1856 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1858 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
1859 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1861 GST_PAD_PEER (srcpad) = NULL;
1862 GST_PAD_PEER (sinkpad) = NULL;
1864 GST_OBJECT_UNLOCK (sinkpad);
1865 GST_OBJECT_UNLOCK (srcpad);
1876 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
1878 GstPadTemplate **template_p;
1880 /* this function would need checks if it weren't static */
1882 GST_OBJECT_LOCK (pad);
1883 template_p = &pad->padtemplate;
1884 gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
1885 GST_OBJECT_UNLOCK (pad);
1888 gst_pad_template_pad_created (templ, pad);
1892 * gst_pad_get_pad_template:
1895 * Gets the template for @pad.
1897 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
1898 * if this pad has no template.
1900 * FIXME: currently returns an unrefcounted padtemplate.
1903 gst_pad_get_pad_template (GstPad * pad)
1905 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1907 return GST_PAD_PAD_TEMPLATE (pad);
1911 /* should be called with the pad LOCK held */
1912 /* refs the caps, so caller is responsible for getting it unreffed */
1914 gst_pad_get_caps_unlocked (GstPad * pad)
1916 GstCaps *result = NULL;
1918 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
1920 if (GST_PAD_GETCAPSFUNC (pad)) {
1921 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1922 "dispatching to pad getcaps function");
1924 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
1925 GST_OBJECT_UNLOCK (pad);
1926 result = GST_PAD_GETCAPSFUNC (pad) (pad);
1927 GST_OBJECT_LOCK (pad);
1928 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
1930 if (result == NULL) {
1931 g_critical ("pad %s:%s returned NULL caps from getcaps function",
1932 GST_DEBUG_PAD_NAME (pad));
1934 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1935 "pad getcaps returned %" GST_PTR_FORMAT, result);
1936 #ifndef G_DISABLE_ASSERT
1937 /* check that the returned caps are a real subset of the template caps */
1938 if (GST_PAD_PAD_TEMPLATE (pad)) {
1939 const GstCaps *templ_caps =
1940 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
1941 if (!gst_caps_is_subset (result, templ_caps)) {
1944 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
1945 "pad returned caps %" GST_PTR_FORMAT
1946 " which are not a real subset of its template caps %"
1947 GST_PTR_FORMAT, result, templ_caps);
1949 ("pad %s:%s returned caps which are not a real "
1950 "subset of its template caps", GST_DEBUG_PAD_NAME (pad));
1951 temp = gst_caps_intersect (templ_caps, result);
1952 gst_caps_unref (result);
1960 if (GST_PAD_PAD_TEMPLATE (pad)) {
1961 GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
1963 result = GST_PAD_TEMPLATE_CAPS (templ);
1964 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1965 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
1968 result = gst_caps_ref (result);
1971 if (GST_PAD_CAPS (pad)) {
1972 result = GST_PAD_CAPS (pad);
1974 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
1975 "using pad caps %p %" GST_PTR_FORMAT, result, result);
1977 result = gst_caps_ref (result);
1981 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
1982 result = gst_caps_new_empty ();
1990 * @pad: a #GstPad to get the capabilities of.
1992 * Gets the capabilities this pad can produce or consume.
1993 * Note that this method doesn't necessarily return the caps set by
1994 * gst_pad_set_caps() - use #GST_PAD_CAPS for that instead.
1995 * gst_pad_get_caps returns all possible caps a pad can operate with, using
1996 * the pad's get_caps function;
1997 * this returns the pad template caps if not explicitly set.
1999 * Returns: a newly allocated copy of the #GstCaps of this pad.
2004 gst_pad_get_caps (GstPad * pad)
2006 GstCaps *result = NULL;
2008 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2010 GST_OBJECT_LOCK (pad);
2012 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
2014 result = gst_pad_get_caps_unlocked (pad);
2015 GST_OBJECT_UNLOCK (pad);
2021 * gst_pad_peer_get_caps:
2022 * @pad: a #GstPad to get the peer capabilities of.
2024 * Gets the capabilities of the peer connected to this pad.
2026 * Returns: the #GstCaps of the peer pad. This function returns a new caps, so use
2027 * gst_caps_unref to get rid of it. this function returns NULL if there is no
2031 gst_pad_peer_get_caps (GstPad * pad)
2034 GstCaps *result = NULL;
2036 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2038 GST_OBJECT_LOCK (pad);
2040 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2042 peerpad = GST_PAD_PEER (pad);
2043 if (G_UNLIKELY (peerpad == NULL))
2046 gst_object_ref (peerpad);
2047 GST_OBJECT_UNLOCK (pad);
2049 result = gst_pad_get_caps (peerpad);
2051 gst_object_unref (peerpad);
2057 GST_OBJECT_UNLOCK (pad);
2063 fixate_value (GValue * dest, const GValue * src)
2065 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
2066 g_value_init (dest, G_TYPE_INT);
2067 g_value_set_int (dest, gst_value_get_int_range_min (src));
2068 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
2069 g_value_init (dest, G_TYPE_DOUBLE);
2070 g_value_set_double (dest, gst_value_get_double_range_min (src));
2071 } else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
2072 gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
2073 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
2074 GValue temp = { 0 };
2076 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
2077 if (!fixate_value (dest, &temp))
2078 gst_value_init_and_copy (dest, &temp);
2079 g_value_unset (&temp);
2080 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
2081 gboolean res = FALSE;
2084 g_value_init (dest, GST_TYPE_ARRAY);
2085 for (n = 0; n < gst_value_array_get_size (src); n++) {
2087 const GValue *orig_kid = gst_value_array_get_value (src, n);
2089 if (!fixate_value (&kid, orig_kid))
2090 gst_value_init_and_copy (&kid, orig_kid);
2093 gst_value_array_append_value (dest, &kid);
2094 g_value_unset (&kid);
2098 g_value_unset (dest);
2109 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
2111 GstStructure *s = data;
2114 if (fixate_value (&v, value)) {
2115 gst_structure_id_set_value (s, field_id, &v);
2123 * gst_pad_fixate_caps:
2124 * @pad: a #GstPad to fixate
2125 * @caps: the #GstCaps to fixate
2127 * Fixate a caps on the given pad. Modifies the caps in place, so you should
2128 * make sure that the caps are actually writable (see gst_caps_make_writable()).
2131 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
2133 GstPadFixateCapsFunction fixatefunc;
2136 g_return_if_fail (GST_IS_PAD (pad));
2137 g_return_if_fail (caps != NULL);
2139 if (gst_caps_is_fixed (caps))
2142 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
2144 fixatefunc (pad, caps);
2147 /* default fixation */
2148 for (n = 0; n < gst_caps_get_size (caps); n++) {
2149 GstStructure *s = gst_caps_get_structure (caps, n);
2151 gst_structure_foreach (s, gst_pad_default_fixate, s);
2155 /* Default accept caps implementation just checks against
2156 * against the allowed caps for the pad */
2158 gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
2160 /* get the caps and see if it intersects to something
2164 gboolean result = FALSE;
2166 allowed = gst_pad_get_caps (pad);
2168 intersect = gst_caps_intersect (allowed, caps);
2170 result = !gst_caps_is_empty (intersect);
2172 gst_caps_unref (allowed);
2173 gst_caps_unref (intersect);
2180 * gst_pad_accept_caps:
2181 * @pad: a #GstPad to check
2182 * @caps: a #GstCaps to check on the pad
2184 * Check if the given pad accepts the caps.
2186 * Returns: TRUE if the pad can accept the caps.
2189 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2192 GstPadAcceptCapsFunction acceptfunc;
2193 GstCaps *existing = NULL;
2195 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2197 /* any pad can be unnegotiated */
2201 /* lock for checking the existing caps */
2202 GST_OBJECT_LOCK (pad);
2203 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2204 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
2205 /* The current caps on a pad are trivially acceptable */
2206 if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
2207 if (caps == existing || gst_caps_is_equal (caps, existing))
2210 GST_OBJECT_UNLOCK (pad);
2212 if (G_LIKELY (acceptfunc)) {
2213 /* we can call the function */
2214 result = acceptfunc (pad, caps);
2216 /* Only null if the element explicitly unset it */
2217 result = gst_pad_acceptcaps_default (pad, caps);
2223 GST_OBJECT_UNLOCK (pad);
2229 * gst_pad_peer_accept_caps:
2230 * @pad: a #GstPad to check the peer of
2231 * @caps: a #GstCaps to check on the pad
2233 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2236 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2239 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2244 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2246 GST_OBJECT_LOCK (pad);
2248 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
2250 peerpad = GST_PAD_PEER (pad);
2251 if (G_UNLIKELY (peerpad == NULL))
2254 result = gst_pad_accept_caps (peerpad, caps);
2255 GST_OBJECT_UNLOCK (pad);
2261 GST_OBJECT_UNLOCK (pad);
2268 * @pad: a #GstPad to set the capabilities of.
2269 * @caps: a #GstCaps to set.
2271 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2272 * caps on the pad will be unreffed. This function refs the caps so you should
2273 * unref if as soon as you don't need it anymore.
2274 * It is possible to set NULL caps, which will make the pad unnegotiated
2277 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2278 * or bad parameters were provided to this function.
2283 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2285 GstPadSetCapsFunction setcaps;
2288 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2289 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2291 GST_OBJECT_LOCK (pad);
2292 existing = GST_PAD_CAPS (pad);
2293 if (existing == caps)
2296 if (gst_caps_is_equal (caps, existing))
2297 goto setting_same_caps;
2299 setcaps = GST_PAD_SETCAPSFUNC (pad);
2301 /* call setcaps function to configure the pad only if the
2302 * caps is not NULL */
2303 if (setcaps != NULL && caps) {
2304 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2305 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2306 GST_OBJECT_UNLOCK (pad);
2307 if (!setcaps (pad, caps))
2309 GST_OBJECT_LOCK (pad);
2310 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2312 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
2316 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2317 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %" GST_PTR_FORMAT, caps);
2318 GST_OBJECT_UNLOCK (pad);
2320 g_object_notify (G_OBJECT (pad), "caps");
2326 GST_OBJECT_UNLOCK (pad);
2331 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2332 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2333 "caps %" GST_PTR_FORMAT " same as existing, updating ptr only", caps);
2334 GST_OBJECT_UNLOCK (pad);
2341 GST_OBJECT_LOCK (pad);
2342 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2343 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2344 "caps %" GST_PTR_FORMAT " could not be set", caps);
2345 GST_OBJECT_UNLOCK (pad);
2352 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2354 GstPadSetCapsFunction setcaps;
2357 setcaps = GST_PAD_SETCAPSFUNC (pad);
2359 /* See if pad accepts the caps - only needed if
2360 * no setcaps function */
2361 if (setcaps == NULL)
2362 if (!gst_pad_accept_caps (pad, caps))
2365 /* set caps on pad if call succeeds */
2366 res = gst_pad_set_caps (pad, caps);
2367 /* no need to unref the caps here, set_caps takes a ref and
2368 * our ref goes away when we leave this function. */
2374 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2375 "caps %" GST_PTR_FORMAT " not accepted", caps);
2380 /* returns TRUE if the src pad could be configured to accept the given caps */
2382 gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
2384 GstPadSetCapsFunction setcaps;
2387 setcaps = GST_PAD_SETCAPSFUNC (pad);
2389 /* See if pad accepts the caps - only needed if
2390 * no setcaps function */
2391 if (setcaps == NULL)
2392 if (!gst_pad_accept_caps (pad, caps))
2396 res = gst_pad_set_caps (pad, caps);
2404 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2405 "caps %" GST_PTR_FORMAT " not accepted", caps);
2411 * gst_pad_get_pad_template_caps:
2412 * @pad: a #GstPad to get the template capabilities from.
2414 * Gets the capabilities for @pad's template.
2416 * Returns: the #GstCaps of this pad template. If you intend to keep a reference
2417 * on the caps, make a copy (see gst_caps_copy ()).
2420 gst_pad_get_pad_template_caps (GstPad * pad)
2422 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2424 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2426 if (GST_PAD_PAD_TEMPLATE (pad))
2427 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2429 return gst_static_caps_get (&anycaps);
2435 * @pad: a #GstPad to get the peer of.
2437 * Gets the peer of @pad. This function refs the peer pad so
2438 * you need to unref it after use.
2440 * Returns: the peer #GstPad. Unref after usage.
2445 gst_pad_get_peer (GstPad * pad)
2449 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2451 GST_OBJECT_LOCK (pad);
2452 result = GST_PAD_PEER (pad);
2454 gst_object_ref (result);
2455 GST_OBJECT_UNLOCK (pad);
2461 * gst_pad_get_allowed_caps:
2462 * @srcpad: a #GstPad, it must a a source pad.
2464 * Gets the capabilities of the allowed media types that can flow through
2465 * @srcpad and its peer. The pad must be a source pad.
2466 * The caller must free the resulting caps.
2468 * Returns: the allowed #GstCaps of the pad link. Free the caps when
2469 * you no longer need it. This function returns NULL when the @srcpad has no
2475 gst_pad_get_allowed_caps (GstPad * srcpad)
2482 g_return_val_if_fail (GST_IS_PAD (srcpad), NULL);
2483 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), NULL);
2485 GST_OBJECT_LOCK (srcpad);
2487 peer = GST_PAD_PEER (srcpad);
2488 if (G_UNLIKELY (peer == NULL))
2491 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "getting allowed caps");
2493 gst_object_ref (peer);
2494 GST_OBJECT_UNLOCK (srcpad);
2495 mycaps = gst_pad_get_caps (srcpad);
2497 peercaps = gst_pad_get_caps (peer);
2498 gst_object_unref (peer);
2500 caps = gst_caps_intersect (mycaps, peercaps);
2501 gst_caps_unref (peercaps);
2502 gst_caps_unref (mycaps);
2504 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, srcpad, "allowed caps %" GST_PTR_FORMAT,
2511 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, srcpad, "no peer");
2512 GST_OBJECT_UNLOCK (srcpad);
2519 * gst_pad_get_negotiated_caps:
2522 * Gets the capabilities of the media type that currently flows through @pad
2525 * This function can be used on both src and sinkpads. Note that srcpads are
2526 * always negotiated before sinkpads so it is possible that the negotiated caps
2527 * on the srcpad do not match the negotiated caps of the peer.
2529 * Returns: the negotiated #GstCaps of the pad link. Free the caps when
2530 * you no longer need it. This function returns NULL when the @pad has no
2531 * peer or is not negotiated yet.
2536 gst_pad_get_negotiated_caps (GstPad * pad)
2541 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2543 GST_OBJECT_LOCK (pad);
2545 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2548 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
2550 caps = GST_PAD_CAPS (pad);
2552 gst_caps_ref (caps);
2553 GST_OBJECT_UNLOCK (pad);
2555 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
2562 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2563 GST_OBJECT_UNLOCK (pad);
2569 /* calls the buffer_alloc function on the given pad */
2570 static GstFlowReturn
2571 gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
2572 GstCaps * caps, GstBuffer ** buf)
2575 GstPadBufferAllocFunction bufferallocfunc;
2577 GST_OBJECT_LOCK (pad);
2578 /* when the pad is flushing we cannot give a buffer */
2579 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2582 bufferallocfunc = pad->bufferallocfunc;
2584 if (offset == GST_BUFFER_OFFSET_NONE) {
2585 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2586 "calling bufferallocfunc &%s (@%p) for size %d offset NONE",
2587 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), bufferallocfunc, size);
2589 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2590 "calling bufferallocfunc &%s (@%p) of for size %d offset %"
2591 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2592 bufferallocfunc, size, offset);
2594 GST_OBJECT_UNLOCK (pad);
2596 /* G_LIKELY for now since most elements don't implement a buffer alloc
2597 * function and there is no default alloc proxy function as this is usually
2599 if (G_LIKELY (bufferallocfunc == NULL))
2602 ret = bufferallocfunc (pad, offset, size, caps, buf);
2603 if (G_UNLIKELY (ret != GST_FLOW_OK))
2605 /* no error, but NULL buffer means fallback to the default */
2606 if (G_UNLIKELY (*buf == NULL))
2609 /* If the buffer alloc function didn't set up the caps like it should,
2611 if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
2612 GST_WARNING_OBJECT (pad,
2613 "Buffer allocation function did not set caps. Setting");
2614 gst_buffer_set_caps (*buf, caps);
2620 /* pad was flushing */
2621 GST_OBJECT_UNLOCK (pad);
2622 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
2623 return GST_FLOW_WRONG_STATE;
2627 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2628 "alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
2633 /* fallback case, allocate a buffer of our own, add pad caps. */
2634 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
2636 *buf = gst_buffer_new_and_alloc (size);
2637 GST_BUFFER_OFFSET (*buf) = offset;
2638 gst_buffer_set_caps (*buf, caps);
2644 static GstFlowReturn
2645 gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
2646 GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
2650 gboolean caps_changed;
2652 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
2653 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
2654 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
2656 GST_OBJECT_LOCK (pad);
2657 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
2658 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
2661 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2664 gst_object_ref (peer);
2665 GST_OBJECT_UNLOCK (pad);
2667 ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
2668 gst_object_unref (peer);
2670 if (G_UNLIKELY (ret != GST_FLOW_OK))
2673 /* FIXME, move capnego this into a base class? */
2674 caps = GST_BUFFER_CAPS (*buf);
2676 /* Lock for checking caps, pretty pointless as the _pad_push() function might
2677 * change it concurrently, one of the problems with automatic caps setting in
2678 * pad_alloc_and_set_caps. Worst case, if does a check too much, but only when
2679 * there is heavy renegotiation going on in both directions. */
2680 GST_OBJECT_LOCK (pad);
2681 caps_changed = caps && caps != GST_PAD_CAPS (pad);
2682 GST_OBJECT_UNLOCK (pad);
2684 /* we got a new datatype on the pad, see if it can handle it */
2685 if (G_UNLIKELY (caps_changed)) {
2686 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
2687 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, setcaps)))
2688 goto not_negotiated;
2694 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
2695 GST_OBJECT_UNLOCK (pad);
2700 /* pad has no peer */
2701 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2702 "called bufferallocfunc but had no peer");
2703 GST_OBJECT_UNLOCK (pad);
2704 return GST_FLOW_NOT_LINKED;
2708 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2709 "alloc function returned error %s", gst_flow_get_name (ret));
2714 gst_buffer_unref (*buf);
2716 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
2717 "alloc function returned unacceptable buffer");
2718 return GST_FLOW_NOT_NEGOTIATED;
2723 * gst_pad_alloc_buffer:
2724 * @pad: a source #GstPad
2725 * @offset: the offset of the new buffer in the stream
2726 * @size: the size of the new buffer
2727 * @caps: the caps of the new buffer
2728 * @buf: a newly allocated buffer
2730 * Allocates a new, empty buffer optimized to push to pad @pad. This
2731 * function only works if @pad is a source pad and has a peer.
2733 * A new, empty #GstBuffer will be put in the @buf argument.
2734 * You need to check the caps of the buffer after performing this
2735 * function and renegotiate to the format if needed.
2737 * Returns: a result code indicating success of the operation. Any
2738 * result code other than #GST_FLOW_OK is an error and @buf should
2740 * An error can occur if the pad is not connected or when the downstream
2741 * peer elements cannot provide an acceptable buffer.
2746 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
2749 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
2753 * gst_pad_alloc_buffer_and_set_caps:
2754 * @pad: a source #GstPad
2755 * @offset: the offset of the new buffer in the stream
2756 * @size: the size of the new buffer
2757 * @caps: the caps of the new buffer
2758 * @buf: a newly allocated buffer
2760 * In addition to the function gst_pad_alloc_buffer(), this function
2761 * automatically calls gst_pad_set_caps() when the caps of the
2762 * newly allocated buffer are different from the @pad caps.
2764 * Returns: a result code indicating success of the operation. Any
2765 * result code other than #GST_FLOW_OK is an error and @buf should
2767 * An error can occur if the pad is not connected or when the downstream
2768 * peer elements cannot provide an acceptable buffer.
2773 gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
2774 GstCaps * caps, GstBuffer ** buf)
2776 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
2780 * gst_pad_get_internal_links_default:
2781 * @pad: the #GstPad to get the internal links of.
2783 * Gets a list of pads to which the given pad is linked to
2784 * inside of the parent element.
2785 * This is the default handler, and thus returns a list of all of the
2786 * pads inside the parent element with opposite direction.
2787 * The caller must free this list after use.
2789 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
2794 gst_pad_get_internal_links_default (GstPad * pad)
2799 GstPadDirection direction;
2801 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2803 direction = pad->direction;
2805 parent = GST_PAD_PARENT (pad);
2809 parent_pads = parent->pads;
2811 while (parent_pads) {
2812 GstPad *parent_pad = GST_PAD_CAST (parent_pads->data);
2814 if (parent_pad->direction != direction) {
2815 res = g_list_prepend (res, parent_pad);
2818 parent_pads = g_list_next (parent_pads);
2825 * gst_pad_get_internal_links:
2826 * @pad: the #GstPad to get the internal links of.
2828 * Gets a list of pads to which the given pad is linked to
2829 * inside of the parent element.
2830 * The caller must free this list after use.
2832 * Returns: a newly allocated #GList of pads.
2837 gst_pad_get_internal_links (GstPad * pad)
2841 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2843 if (GST_PAD_INTLINKFUNC (pad))
2844 res = GST_PAD_INTLINKFUNC (pad) (pad);
2851 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
2856 GST_INFO_OBJECT (pad, "Sending event %p to all internally linked pads",
2859 result = (GST_PAD_DIRECTION (pad) == GST_PAD_SINK);
2861 orig = pads = gst_pad_get_internal_links (pad);
2864 GstPad *eventpad = GST_PAD_CAST (pads->data);
2866 pads = g_list_next (pads);
2868 if (GST_PAD_DIRECTION (eventpad) == GST_PAD_SRC) {
2869 /* for each pad we send to, we should ref the event; it's up
2870 * to downstream to unref again when handled. */
2871 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
2872 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2873 gst_event_ref (event);
2874 gst_pad_push_event (eventpad, event);
2876 /* we only send the event on one pad, multi-sinkpad elements
2877 * should implement a handler */
2878 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
2879 event, GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (eventpad));
2880 result = gst_pad_push_event (eventpad, event);
2884 /* we handled the incoming event so we unref once */
2885 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
2886 gst_event_unref (event);
2895 * gst_pad_event_default:
2896 * @pad: a #GstPad to call the default event handler on.
2897 * @event: the #GstEvent to handle.
2899 * Invokes the default event handler for the given pad. End-of-stream and
2900 * discontinuity events are handled specially, and then the event is sent to all
2901 * pads internally linked to @pad. Note that if there are many possible sink
2902 * pads that are internally linked to @pad, only one will be sent an event.
2903 * Multi-sinkpad elements should implement custom event handlers.
2905 * Returns: TRUE if the event was sent succesfully.
2908 gst_pad_event_default (GstPad * pad, GstEvent * event)
2910 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2911 g_return_val_if_fail (event != NULL, FALSE);
2913 switch (GST_EVENT_TYPE (event)) {
2916 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
2917 gst_pad_pause_task (pad);
2923 return gst_pad_event_default_dispatch (pad, event);
2927 * gst_pad_dispatcher:
2928 * @pad: a #GstPad to dispatch.
2929 * @dispatch: the #GstDispatcherFunction to call.
2930 * @data: gpointer user data passed to the dispatcher function.
2932 * Invokes the given dispatcher function on all pads that are
2933 * internally linked to the given pad.
2934 * The GstPadDispatcherFunction should return TRUE when no further pads
2935 * need to be processed.
2937 * Returns: TRUE if one of the dispatcher functions returned TRUE.
2940 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
2943 gboolean res = FALSE;
2944 GList *int_pads, *orig;
2946 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2947 g_return_val_if_fail (dispatch != NULL, FALSE);
2949 orig = int_pads = gst_pad_get_internal_links (pad);
2952 GstPad *int_pad = GST_PAD_CAST (int_pads->data);
2953 GstPad *int_peer = GST_PAD_PEER (int_pad);
2956 res = dispatch (int_peer, data);
2960 int_pads = g_list_next (int_pads);
2970 * @pad: a #GstPad to invoke the default query on.
2971 * @query: the #GstQuery to perform.
2973 * Dispatches a query to a pad. The query should have been allocated by the
2974 * caller via one of the type-specific allocation functions in gstquery.h. The
2975 * element is responsible for filling the query with an appropriate response,
2976 * which should then be parsed with a type-specific query parsing function.
2978 * Again, the caller is responsible for both the allocation and deallocation of
2979 * the query structure.
2981 * Returns: TRUE if the query could be performed.
2984 gst_pad_query (GstPad * pad, GstQuery * query)
2986 GstPadQueryFunction func;
2988 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2989 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
2991 GST_DEBUG_OBJECT (pad, "sending query %p", query);
2993 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
2996 return func (pad, query);
3000 GST_DEBUG_OBJECT (pad, "had no query function");
3006 * gst_pad_query_default:
3007 * @pad: a #GstPad to call the default query handler on.
3008 * @query: the #GstQuery to handle.
3010 * Invokes the default query handler for the given pad.
3011 * The query is sent to all pads internally linked to @pad. Note that
3012 * if there are many possible sink pads that are internally linked to
3013 * @pad, only one will be sent the query.
3014 * Multi-sinkpad elements should implement custom query handlers.
3016 * Returns: TRUE if the query was performed succesfully.
3019 gst_pad_query_default (GstPad * pad, GstQuery * query)
3021 switch (GST_QUERY_TYPE (query)) {
3022 case GST_QUERY_POSITION:
3023 case GST_QUERY_SEEKING:
3024 case GST_QUERY_FORMATS:
3025 case GST_QUERY_LATENCY:
3026 case GST_QUERY_JITTER:
3027 case GST_QUERY_RATE:
3028 case GST_QUERY_CONVERT:
3030 return gst_pad_dispatcher
3031 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
3035 #ifndef GST_DISABLE_LOADSAVE
3036 /* FIXME: why isn't this on a GstElement ? */
3038 * gst_pad_load_and_link:
3039 * @self: an #xmlNodePtr to read the description from.
3040 * @parent: the #GstObject element that owns the pad.
3042 * Reads the pad definition from the XML node and links the given pad
3043 * in the element to a pad of an element up in the hierarchy.
3046 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
3048 xmlNodePtr field = self->xmlChildrenNode;
3049 GstPad *pad = NULL, *targetpad;
3053 GstObject *grandparent;
3057 if (!strcmp ((char *) field->name, "name")) {
3058 name = (gchar *) xmlNodeGetContent (field);
3059 pad = gst_element_get_pad (GST_ELEMENT (parent), name);
3061 } else if (!strcmp ((char *) field->name, "peer")) {
3062 peer = (gchar *) xmlNodeGetContent (field);
3064 field = field->next;
3066 g_return_if_fail (pad != NULL);
3071 split = g_strsplit (peer, ".", 2);
3073 if (split[0] == NULL || split[1] == NULL) {
3074 GST_CAT_DEBUG_OBJECT (GST_CAT_XML, pad,
3075 "Could not parse peer '%s', leaving unlinked", peer);
3082 g_return_if_fail (split[0] != NULL);
3083 g_return_if_fail (split[1] != NULL);
3085 grandparent = gst_object_get_parent (parent);
3087 if (grandparent && GST_IS_BIN (grandparent)) {
3088 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
3095 targetpad = gst_element_get_pad (target, split[1]);
3097 if (targetpad == NULL)
3100 gst_pad_link (pad, targetpad);
3107 * gst_pad_save_thyself:
3108 * @pad: a #GstPad to save.
3109 * @parent: the parent #xmlNodePtr to save the description in.
3111 * Saves the pad into an xml representation.
3113 * Returns: the #xmlNodePtr representation of the pad.
3116 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
3121 g_return_val_if_fail (GST_IS_PAD (object), NULL);
3123 pad = GST_PAD (object);
3125 xmlNewChild (parent, NULL, (xmlChar *) "name",
3126 (xmlChar *) GST_PAD_NAME (pad));
3128 if (GST_PAD_IS_SRC (pad)) {
3129 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "source");
3130 } else if (GST_PAD_IS_SINK (pad)) {
3131 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "sink");
3133 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "unknown");
3136 if (GST_PAD_PEER (pad) != NULL) {
3139 peer = GST_PAD_PEER (pad);
3140 /* first check to see if the peer's parent's parent is the same */
3141 /* we just save it off */
3142 content = g_strdup_printf ("%s.%s",
3143 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
3144 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
3147 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
3154 * gst_ghost_pad_save_thyself:
3155 * @pad: a ghost #GstPad to save.
3156 * @parent: the parent #xmlNodePtr to save the description in.
3158 * Saves the ghost pad into an xml representation.
3160 * Returns: the #xmlNodePtr representation of the pad.
3163 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
3167 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
3169 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
3170 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
3171 xmlNewChild (self, NULL, (xmlChar *) "parent",
3172 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
3174 /* FIXME FIXME FIXME! */
3179 #endif /* GST_DISABLE_LOADSAVE */
3182 * should be called with pad OBJECT_LOCK and STREAM_LOCK held.
3183 * GST_PAD_IS_BLOCKED (pad) == TRUE when this function is
3186 * This function perform the pad blocking when an event, buffer push
3187 * or buffer_alloc is performed on a _SRC_ pad. It blocks the
3188 * streaming thread after informing the pad has been blocked.
3190 * An application can with this method wait and block any streaming
3191 * thread and perform operations such as seeking or linking.
3193 * Two methods are available for notifying the application of the
3195 * - the callback method, which happens in the STREAMING thread with
3196 * the STREAM_LOCK held. With this method, the most usefull way of
3197 * dealing with the callback is to post a message to the main thread
3198 * where the pad block can then be handled outside of the streaming
3199 * thread. With the last method one can perform all operations such
3200 * as doing a state change, linking, unblocking, seeking etc on the
3202 * - the GCond signal method, which makes any thread unblock when
3203 * the pad block happens.
3205 * During the actual blocking state, the GST_PAD_BLOCKING flag is set.
3206 * The GST_PAD_BLOCKING flag is unset when the GST_PAD_FLUSHING flag is
3207 * unset. This is to know whether the pad was blocking when GST_PAD_FLUSHING
3212 static GstFlowReturn
3213 handle_pad_block (GstPad * pad)
3215 GstPadBlockCallback callback;
3217 GstFlowReturn ret = GST_FLOW_OK;
3219 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
3221 /* flushing, don't bother trying to block and return WRONG_STATE
3223 if (GST_PAD_IS_FLUSHING (pad))
3224 goto flushingnonref;
3226 /* we grab an extra ref for the callbacks, this is probably not
3227 * needed (callback code does not have a ref and cannot unref). I
3228 * think this was done to make it possible to unref the element in
3229 * the callback, which is in the end totally impossible as it
3230 * requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
3231 * all taken when calling this function. */
3232 gst_object_ref (pad);
3234 /* we either have a callback installed to notify the block or
3235 * some other thread is doing a GCond wait. */
3236 callback = pad->block_callback;
3238 /* there is a callback installed, call it. We release the
3239 * lock so that the callback can do something usefull with the
3241 user_data = pad->block_data;
3242 GST_OBJECT_UNLOCK (pad);
3243 callback (pad, TRUE, user_data);
3244 GST_OBJECT_LOCK (pad);
3246 /* no callback, signal the thread that is doing a GCond wait
3248 GST_PAD_BLOCK_SIGNAL (pad);
3251 /* OBJECT_LOCK could have been released when we did the callback, which
3252 * then could have made the pad unblock so we need to check the blocking
3253 * condition again. */
3254 while (GST_PAD_IS_BLOCKED (pad)) {
3255 if (GST_PAD_IS_FLUSHING (pad))
3258 /* now we block the streaming thread. It can be unlocked when we
3259 * deactivate the pad (which will also set the FLUSHING flag) or
3260 * when the pad is unblocked. A flushing event will also unblock
3261 * the pad after setting the FLUSHING flag. */
3262 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3263 "Waiting to be unblocked or set flushing");
3264 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKING);
3265 GST_PAD_BLOCK_WAIT (pad);
3267 /* see if we got unlocked by a flush or not */
3268 if (GST_PAD_IS_FLUSHING (pad))
3272 /* If we made it here we either never blocked, or were unblocked because we
3273 * weren't flushing, it is therefore safe to remove the BLOCKING flag */
3274 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKING);
3276 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
3278 /* when we get here, the pad is unblocked again and we perform
3279 * the needed unblock code. */
3280 callback = pad->block_callback;
3282 /* we need to call the callback */
3283 user_data = pad->block_data;
3284 GST_OBJECT_UNLOCK (pad);
3285 callback (pad, FALSE, user_data);
3286 GST_OBJECT_LOCK (pad);
3288 /* we need to signal the thread waiting on the GCond */
3289 GST_PAD_BLOCK_SIGNAL (pad);
3292 gst_object_unref (pad);
3298 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
3299 return GST_FLOW_WRONG_STATE;
3303 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
3304 gst_object_unref (pad);
3305 return GST_FLOW_WRONG_STATE;
3309 /**********************************************************************
3310 * Data passing functions
3314 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
3317 GValue args[2] = { {0}, {0} };
3322 g_value_init (&ret, G_TYPE_BOOLEAN);
3323 g_value_set_boolean (&ret, TRUE);
3324 g_value_init (&args[0], GST_TYPE_PAD);
3325 g_value_set_object (&args[0], pad);
3326 g_value_init (&args[1], GST_TYPE_MINI_OBJECT); // G_TYPE_POINTER);
3327 gst_value_set_mini_object (&args[1], obj);
3329 if (GST_IS_EVENT (obj))
3330 detail = event_quark;
3332 detail = buffer_quark;
3335 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
3336 res = g_value_get_boolean (&ret);
3339 g_value_unset (&ret);
3340 g_value_unset (&args[0]);
3341 g_value_unset (&args[1]);
3346 /* this is the chain function that does not perform the additional argument
3347 * checking for that little extra speed.
3349 static inline GstFlowReturn
3350 gst_pad_chain_unchecked (GstPad * pad, GstBuffer * buffer)
3353 gboolean caps_changed;
3354 GstPadChainFunction chainfunc;
3356 gboolean emit_signal;
3358 GST_PAD_STREAM_LOCK (pad);
3360 GST_OBJECT_LOCK (pad);
3361 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3364 caps = GST_BUFFER_CAPS (buffer);
3365 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3367 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3368 GST_OBJECT_UNLOCK (pad);
3370 /* see if the signal should be emited, we emit before caps nego as
3371 * we might drop the buffer and do capsnego for nothing. */
3372 if (G_UNLIKELY (emit_signal)) {
3373 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3377 /* we got a new datatype on the pad, see if it can handle it */
3378 if (G_UNLIKELY (caps_changed)) {
3379 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3380 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
3381 goto not_negotiated;
3384 /* NOTE: we read the chainfunc unlocked.
3385 * we cannot hold the lock for the pad so we might send
3386 * the data to the wrong function. This is not really a
3387 * problem since functions are assigned at creation time
3388 * and don't change that often... */
3389 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
3392 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3393 "calling chainfunction &%s", GST_DEBUG_FUNCPTR_NAME (chainfunc));
3395 ret = chainfunc (pad, buffer);
3397 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3398 "called chainfunction &%s, returned %s",
3399 GST_DEBUG_FUNCPTR_NAME (chainfunc), gst_flow_get_name (ret));
3401 GST_PAD_STREAM_UNLOCK (pad);
3408 gst_buffer_unref (buffer);
3409 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3410 "pushing, but pad was flushing");
3411 GST_OBJECT_UNLOCK (pad);
3412 GST_PAD_STREAM_UNLOCK (pad);
3413 return GST_FLOW_WRONG_STATE;
3417 gst_buffer_unref (buffer);
3418 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3419 GST_PAD_STREAM_UNLOCK (pad);
3424 gst_buffer_unref (buffer);
3425 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3426 "pushing buffer but pad did not accept");
3427 GST_PAD_STREAM_UNLOCK (pad);
3428 return GST_FLOW_NOT_NEGOTIATED;
3432 gst_buffer_unref (buffer);
3433 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3434 "pushing, but not chainhandler");
3435 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3436 ("push on pad %s:%s but it has no chainfunction",
3437 GST_DEBUG_PAD_NAME (pad)));
3438 GST_PAD_STREAM_UNLOCK (pad);
3439 return GST_FLOW_NOT_SUPPORTED;
3445 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3446 * @buffer: the #GstBuffer to send, return GST_FLOW_ERROR if not.
3448 * Chain a buffer to @pad.
3450 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
3452 * If the caps on @buffer are different from the current caps on @pad, this
3453 * function will call any setcaps function (see gst_pad_set_setcaps_function())
3454 * installed on @pad. If the new caps are not acceptable for @pad, this function
3455 * returns #GST_FLOW_NOT_NEGOTIATED.
3457 * The function proceeds calling the chain function installed on @pad (see
3458 * gst_pad_set_chain_function()) and the return value of that function is
3459 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
3462 * In all cases, success or failure, the caller loses its reference to @buffer
3463 * after calling this function.
3465 * Returns: a #GstFlowReturn from the pad.
3470 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
3472 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3473 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3475 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3477 return gst_pad_chain_unchecked (pad, buffer);
3482 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
3483 * @buffer: the #GstBuffer to push returns GST_FLOW_ERROR if not.
3485 * Pushes a buffer to the peer of @pad.
3487 * This function will call an installed pad block before triggering any
3488 * installed pad probes.
3490 * If the caps on @buffer are different from the currently configured caps on
3491 * @pad, this function will call any installed setcaps function on @pad (see
3492 * gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
3493 * format, this function returns #GST_FLOW_NOT_NEGOTIATED.
3495 * The function proceeds calling gst_pad_chain() on the peer pad and returns the
3496 * value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will be
3499 * In all cases, success or failure, the caller loses its reference to @buffer
3500 * after calling this function.
3502 * Returns: a #GstFlowReturn from the peer pad.
3507 gst_pad_push (GstPad * pad, GstBuffer * buffer)
3513 gboolean caps_changed;
3515 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3516 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3517 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
3519 GST_OBJECT_LOCK (pad);
3521 /* FIXME: this check can go away; pad_set_blocked could be implemented with
3522 * probes completely or probes with an extended pad block. */
3523 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3524 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
3527 /* we emit signals on the pad arg, the peer will have a chance to
3528 * emit in the _chain() function */
3529 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
3530 /* unlock before emitting */
3531 GST_OBJECT_UNLOCK (pad);
3533 /* if the signal handler returned FALSE, it means we should just drop the
3535 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (buffer)))
3538 GST_OBJECT_LOCK (pad);
3541 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3544 /* take ref to peer pad before releasing the lock */
3545 gst_object_ref (peer);
3547 /* Before pushing the buffer to the peer pad, ensure that caps
3548 * are set on this pad */
3549 caps = GST_BUFFER_CAPS (buffer);
3550 caps_changed = caps && caps != GST_PAD_CAPS (pad);
3552 GST_OBJECT_UNLOCK (pad);
3554 /* we got a new datatype from the pad, it had better handle it */
3555 if (G_UNLIKELY (caps_changed)) {
3556 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
3557 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
3558 goto not_negotiated;
3561 ret = gst_pad_chain_unchecked (peer, buffer);
3563 gst_object_unref (peer);
3567 /* ERROR recovery here */
3570 gst_buffer_unref (buffer);
3571 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
3572 GST_OBJECT_UNLOCK (pad);
3577 gst_buffer_unref (buffer);
3578 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
3583 gst_buffer_unref (buffer);
3584 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3585 "pushing, but it was not linked");
3586 GST_OBJECT_UNLOCK (pad);
3587 return GST_FLOW_NOT_LINKED;
3591 gst_buffer_unref (buffer);
3592 gst_object_unref (peer);
3593 GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
3594 "element pushed buffer then refused to accept the caps");
3595 return GST_FLOW_NOT_NEGOTIATED;
3600 * gst_pad_check_pull_range:
3601 * @pad: a sink #GstPad.
3603 * Checks if a gst_pad_pull_range() can be performed on the peer
3604 * source pad. This function is used by plugins that want to check
3605 * if they can use random access on the peer source pad.
3607 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
3608 * if it needs to perform some logic to determine if pull_range is
3611 * Returns: a gboolean with the result.
3616 gst_pad_check_pull_range (GstPad * pad)
3620 GstPadCheckGetRangeFunction checkgetrangefunc;
3622 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3624 GST_OBJECT_LOCK (pad);
3625 if (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)
3626 goto wrong_direction;
3628 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3631 gst_object_ref (peer);
3632 GST_OBJECT_UNLOCK (pad);
3634 /* see note in above function */
3635 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
3636 /* FIXME, kindoff ghetto */
3637 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
3639 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3640 "calling checkgetrangefunc %s of peer pad %s:%s",
3641 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
3643 ret = checkgetrangefunc (peer);
3646 gst_object_unref (peer);
3650 /* ERROR recovery here */
3653 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3654 "checking pull range, but pad must be a sinkpad");
3655 GST_OBJECT_UNLOCK (pad);
3660 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3661 "checking pull range, but it was not linked");
3662 GST_OBJECT_UNLOCK (pad);
3668 * gst_pad_get_range:
3669 * @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
3670 * @offset: The start offset of the buffer
3671 * @size: The length of the buffer
3672 * @buffer: a pointer to hold the #GstBuffer, returns #GST_FLOW_ERROR if %NULL.
3674 * When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
3677 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
3678 * description of a getrange function. If @pad has no getrange function
3679 * installed (see gst_pad_set_getrange_function()) this function returns
3680 * #GST_FLOW_NOT_SUPPORTED.
3682 * Returns: a #GstFlowReturn from the pad.
3687 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
3688 GstBuffer ** buffer)
3691 GstPadGetRangeFunction getrangefunc;
3692 gboolean emit_signal;
3694 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3695 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SRC, GST_FLOW_ERROR);
3696 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3698 GST_PAD_STREAM_LOCK (pad);
3700 GST_OBJECT_LOCK (pad);
3701 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
3704 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3705 GST_OBJECT_UNLOCK (pad);
3707 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
3710 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3711 "calling getrangefunc %s, offset %"
3712 G_GUINT64_FORMAT ", size %u",
3713 GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
3715 ret = getrangefunc (pad, offset, size, buffer);
3717 /* can only fire the signal if we have a valid buffer */
3718 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3719 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3723 GST_PAD_STREAM_UNLOCK (pad);
3730 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3731 "pulling range, but pad was flushing");
3732 GST_OBJECT_UNLOCK (pad);
3733 GST_PAD_STREAM_UNLOCK (pad);
3734 return GST_FLOW_WRONG_STATE;
3738 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
3739 ("pullrange on pad %s:%s but it has no getrangefunction",
3740 GST_DEBUG_PAD_NAME (pad)));
3741 GST_PAD_STREAM_UNLOCK (pad);
3742 return GST_FLOW_NOT_SUPPORTED;
3746 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3747 "Dropping data after FALSE probe return");
3748 GST_PAD_STREAM_UNLOCK (pad);
3749 gst_buffer_unref (*buffer);
3751 return GST_FLOW_UNEXPECTED;
3757 * gst_pad_pull_range:
3758 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
3759 * @offset: The start offset of the buffer
3760 * @size: The length of the buffer
3761 * @buffer: a pointer to hold the #GstBuffer, returns GST_FLOW_ERROR if %NULL.
3763 * Pulls a buffer from the peer pad.
3765 * This function will first trigger the pad block signal if it was
3768 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
3769 * function returns the result of gst_pad_get_range() on the peer pad.
3770 * See gst_pad_get_range() for a list of return values and for the
3771 * semantics of the arguments of this function.
3773 * Returns: a #GstFlowReturn from the peer pad.
3774 * When this function returns #GST_FLOW_OK, @buffer will contain a valid
3775 * #GstBuffer that should be freed with gst_buffer_unref() after usage.
3776 * @buffer may not be used or freed when any other return value than
3777 * #GST_FLOW_OK is returned.
3782 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
3783 GstBuffer ** buffer)
3787 gboolean emit_signal;
3789 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3790 g_return_val_if_fail (GST_PAD_DIRECTION (pad) == GST_PAD_SINK,
3792 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
3794 GST_OBJECT_LOCK (pad);
3796 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3797 handle_pad_block (pad);
3799 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3802 /* signal emision for the pad, peer has chance to emit when
3803 * we call _get_range() */
3804 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
3806 gst_object_ref (peer);
3807 GST_OBJECT_UNLOCK (pad);
3809 ret = gst_pad_get_range (peer, offset, size, buffer);
3811 gst_object_unref (peer);
3813 /* can only fire the signal if we have a valid buffer */
3814 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
3815 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
3820 /* ERROR recovery here */
3823 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3824 "pulling range, but it was not linked");
3825 GST_OBJECT_UNLOCK (pad);
3826 return GST_FLOW_NOT_LINKED;
3830 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3831 "Dropping data after FALSE probe return");
3832 gst_buffer_unref (*buffer);
3834 return GST_FLOW_UNEXPECTED;
3839 * gst_pad_push_event:
3840 * @pad: a #GstPad to push the event to.
3841 * @event: the #GstEvent to send to the pad.
3843 * Sends the event to the peer of the given pad. This function is
3844 * mainly used by elements to send events to their peer
3847 * This function takes owership of the provided event so you should
3848 * gst_event_ref() it if you want to reuse the event after this call.
3850 * Returns: TRUE if the event was handled.
3855 gst_pad_push_event (GstPad * pad, GstEvent * event)
3860 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3861 g_return_val_if_fail (event != NULL, FALSE);
3862 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
3864 GST_LOG_OBJECT (pad, "event:%s", GST_EVENT_TYPE_NAME (event));
3866 GST_OBJECT_LOCK (pad);
3868 /* Two checks to be made:
3869 * . (un)set the FLUSHING flag for flushing events,
3870 * . handle pad blocking */
3871 switch (GST_EVENT_TYPE (event)) {
3872 case GST_EVENT_FLUSH_START:
3873 GST_PAD_SET_FLUSHING (pad);
3875 if (G_UNLIKELY (GST_PAD_IS_BLOCKING (pad))) {
3876 /* flush start will have set the FLUSHING flag and will then
3877 * unlock all threads doing a GCond wait on the blocking pad. This
3878 * will typically unblock the STREAMING thread blocked on a pad. */
3879 GST_PAD_BLOCK_SIGNAL (pad);
3883 case GST_EVENT_FLUSH_STOP:
3884 GST_PAD_UNSET_FLUSHING (pad);
3886 /* If pad was blocking on something when the pad received flush-start, we
3887 * don't forward the flush-stop event either. */
3888 if (G_UNLIKELY (GST_PAD_IS_BLOCKING (pad))) {
3889 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKING);
3890 GST_LOG_OBJECT (pad,
3891 "Pad was previously blocking, not forwarding flush-stop");
3894 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKING);
3897 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
3898 if (GST_PAD_IS_FLUSHING (pad))
3900 while (GST_PAD_IS_BLOCKED (pad))
3901 /* else block the event as long as the pad is blocked */
3902 if (handle_pad_block (pad) != GST_FLOW_OK)
3908 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
3909 GST_OBJECT_UNLOCK (pad);
3911 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
3914 GST_OBJECT_LOCK (pad);
3916 peerpad = GST_PAD_PEER (pad);
3917 if (peerpad == NULL)
3920 GST_LOG_OBJECT (pad, "sending event to peerpad %" GST_PTR_FORMAT, peerpad);
3921 gst_object_ref (peerpad);
3922 GST_OBJECT_UNLOCK (pad);
3924 result = gst_pad_send_event (peerpad, event);
3926 GST_LOG_OBJECT (pad, "sent event to peerpad %" GST_PTR_FORMAT, peerpad);
3927 gst_object_unref (peerpad);
3931 /* ERROR handling */
3934 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
3935 gst_event_unref (event);
3940 GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
3941 gst_event_unref (event);
3942 GST_OBJECT_UNLOCK (pad);
3948 GST_DEBUG_OBJECT (pad,
3949 "Not forwarding event since we're flushing and blocking");
3950 gst_event_unref (event);
3951 GST_OBJECT_UNLOCK (pad);
3957 * gst_pad_send_event:
3958 * @pad: a #GstPad to send the event to.
3959 * @event: the #GstEvent to send to the pad.
3961 * Sends the event to the pad. This function can be used
3962 * by applications to send events in the pipeline.
3964 * If @pad is a source pad, @event should be an upstream event. If @pad is a
3965 * sink pad, @event should be a downstream event. For example, you would not
3966 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
3967 * Furthermore, some downstream events have to be serialized with data flow,
3968 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
3969 * the event needs to be serialized with data flow, this function will take the
3970 * pad's stream lock while calling its event function.
3972 * To find out whether an event type is upstream, downstream, or downstream and
3973 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
3974 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
3975 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or plugin
3976 * doesn't need to bother itself with this information; the core handles all
3977 * necessary locks and checks.
3979 * This function takes owership of the provided event so you should
3980 * gst_event_ref() it if you want to reuse the event after this call.
3982 * Returns: TRUE if the event was handled.
3985 gst_pad_send_event (GstPad * pad, GstEvent * event)
3987 gboolean result = FALSE;
3988 GstPadEventFunction eventfunc;
3989 gboolean serialized, need_unlock = FALSE;
3991 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3992 g_return_val_if_fail (event != NULL, FALSE);
3994 GST_OBJECT_LOCK (pad);
3995 if (GST_PAD_IS_SINK (pad)) {
3996 if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
3997 goto wrong_direction;
3998 serialized = GST_EVENT_IS_SERIALIZED (event);
3999 } else if (GST_PAD_IS_SRC (pad)) {
4000 if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
4001 goto wrong_direction;
4002 /* events on srcpad never are serialized */
4005 goto unknown_direction;
4007 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
4008 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
4009 GST_EVENT_SRC (event) = gst_object_ref (pad);
4013 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
4014 GST_OBJECT_UNLOCK (pad);
4016 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
4019 GST_OBJECT_LOCK (pad);
4022 switch (GST_EVENT_TYPE (event)) {
4023 case GST_EVENT_FLUSH_START:
4024 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
4025 "have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
4027 /* can't even accept a flush begin event when flushing */
4028 if (GST_PAD_IS_FLUSHING (pad))
4030 GST_PAD_SET_FLUSHING (pad);
4031 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
4033 case GST_EVENT_FLUSH_STOP:
4034 GST_PAD_UNSET_FLUSHING (pad);
4035 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
4036 GST_OBJECT_UNLOCK (pad);
4037 /* grab stream lock */
4038 GST_PAD_STREAM_LOCK (pad);
4040 GST_OBJECT_LOCK (pad);
4043 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
4044 GST_EVENT_TYPE_NAME (event));
4046 /* make this a little faster, no point in grabbing the lock
4047 * if the pad is allready flushing. */
4048 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4052 /* lock order: STREAM_LOCK, LOCK */
4053 GST_OBJECT_UNLOCK (pad);
4054 GST_PAD_STREAM_LOCK (pad);
4056 GST_OBJECT_LOCK (pad);
4057 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4062 if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
4065 GST_OBJECT_UNLOCK (pad);
4067 result = eventfunc (pad, event);
4070 GST_PAD_STREAM_UNLOCK (pad);
4074 /* ERROR handling */
4077 g_warning ("pad %s:%s sending %s event in wrong direction",
4078 GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
4079 GST_OBJECT_UNLOCK (pad);
4080 gst_event_unref (event);
4085 g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
4086 GST_OBJECT_UNLOCK (pad);
4087 gst_event_unref (event);
4092 g_warning ("pad %s:%s has no event handler, file a bug.",
4093 GST_DEBUG_PAD_NAME (pad));
4094 GST_OBJECT_UNLOCK (pad);
4095 gst_event_unref (event);
4100 GST_OBJECT_UNLOCK (pad);
4102 GST_PAD_STREAM_UNLOCK (pad);
4103 GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
4104 "Received event on flushing pad. Discarding");
4105 gst_event_unref (event);
4110 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
4111 gst_event_unref (event);
4117 * gst_pad_set_element_private:
4118 * @pad: the #GstPad to set the private data of.
4119 * @priv: The private data to attach to the pad.
4121 * Set the given private data gpointer on the pad.
4122 * This function can only be used by the element that owns the pad.
4123 * No locking is performed in this function.
4126 gst_pad_set_element_private (GstPad * pad, gpointer priv)
4128 pad->element_private = priv;
4132 * gst_pad_get_element_private:
4133 * @pad: the #GstPad to get the private data of.
4135 * Gets the private data of a pad.
4136 * No locking is performed in this function.
4138 * Returns: a #gpointer to the private data.
4141 gst_pad_get_element_private (GstPad * pad)
4143 return pad->element_private;
4147 * gst_pad_start_task:
4148 * @pad: the #GstPad to start the task of
4149 * @func: the task function to call
4150 * @data: data passed to the task function
4152 * Starts a task that repeadedly calls @func with @data. This function
4153 * is nostly used in the pad activation function to start the
4154 * dataflow. This function will automatically acquire the STREAM_LOCK of
4155 * the pad before calling @func.
4157 * Returns: a TRUE if the task could be started.
4160 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
4164 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4165 g_return_val_if_fail (func != NULL, FALSE);
4167 GST_DEBUG_OBJECT (pad, "start task");
4169 GST_OBJECT_LOCK (pad);
4170 task = GST_PAD_TASK (pad);
4172 task = gst_task_create (func, data);
4173 gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
4174 GST_PAD_TASK (pad) = task;
4175 GST_DEBUG_OBJECT (pad, "created task");
4177 gst_task_start (task);
4178 GST_OBJECT_UNLOCK (pad);
4184 * gst_pad_pause_task:
4185 * @pad: the #GstPad to pause the task of
4187 * Pause the task of @pad. This function will also make sure that the
4188 * function executed by the task will effectively stop.
4190 * Returns: a TRUE if the task could be paused or FALSE when the pad
4194 gst_pad_pause_task (GstPad * pad)
4198 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4200 GST_DEBUG_OBJECT (pad, "pause task");
4202 GST_OBJECT_LOCK (pad);
4203 task = GST_PAD_TASK (pad);
4206 gst_task_pause (task);
4207 GST_OBJECT_UNLOCK (pad);
4209 GST_PAD_STREAM_LOCK (pad);
4210 GST_PAD_STREAM_UNLOCK (pad);
4216 GST_DEBUG_OBJECT (pad, "pad has no task");
4217 GST_OBJECT_UNLOCK (pad);
4223 * gst_pad_stop_task:
4224 * @pad: the #GstPad to stop the task of
4226 * Stop the task of @pad. This function will also make sure that the
4227 * function executed by the task will effectively stop if not called
4228 * from the GstTaskFunction.
4230 * This function will deadlock if called from the GstTaskFunction of
4231 * the task. Use gst_task_pause() instead.
4233 * Regardless of whether the pad has a task, the stream lock is acquired and
4234 * released so as to ensure that streaming through this pad has finished.
4236 * Returns: a TRUE if the task could be stopped or FALSE on error.
4239 gst_pad_stop_task (GstPad * pad)
4243 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4245 GST_DEBUG_OBJECT (pad, "stop task");
4247 GST_OBJECT_LOCK (pad);
4248 task = GST_PAD_TASK (pad);
4251 GST_PAD_TASK (pad) = NULL;
4252 gst_task_stop (task);
4253 GST_OBJECT_UNLOCK (pad);
4255 GST_PAD_STREAM_LOCK (pad);
4256 GST_PAD_STREAM_UNLOCK (pad);
4258 if (!gst_task_join (task))
4261 gst_object_unref (task);
4267 GST_DEBUG_OBJECT (pad, "no task");
4268 GST_OBJECT_UNLOCK (pad);
4270 GST_PAD_STREAM_LOCK (pad);
4271 GST_PAD_STREAM_UNLOCK (pad);
4273 /* this is not an error */
4278 /* this is bad, possibly the application tried to join the task from
4279 * the task's thread. We install the task again so that it will be stopped
4280 * again from the right thread next time hopefully. */
4281 GST_OBJECT_LOCK (pad);
4282 GST_DEBUG_OBJECT (pad, "join failed");
4283 /* we can only install this task if there was no other task */
4284 if (GST_PAD_TASK (pad) == NULL)
4285 GST_PAD_TASK (pad) = task;
4286 GST_OBJECT_UNLOCK (pad);