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 typedef struct _GstPadPushCache GstPadPushCache;
100 struct _GstPadPushCache
102 GstPad *peer; /* reffed peer pad */
103 GstCaps *caps; /* caps for this link */
106 static GstPadPushCache _pad_cache_invalid = { NULL, };
108 #define PAD_CACHE_INVALID (&_pad_cache_invalid)
110 #define GST_PAD_GET_PRIVATE(obj) \
111 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PAD, GstPadPrivate))
113 #define GST_PAD_CHAINLISTFUNC(pad) ((pad)->abidata.ABI.priv->chainlistfunc)
115 struct _GstPadPrivate
117 GstPadChainListFunction chainlistfunc;
119 GstPadPushCache *cache_ptr;
122 static void gst_pad_dispose (GObject * object);
123 static void gst_pad_finalize (GObject * object);
124 static void gst_pad_set_property (GObject * object, guint prop_id,
125 const GValue * value, GParamSpec * pspec);
126 static void gst_pad_get_property (GObject * object, guint prop_id,
127 GValue * value, GParamSpec * pspec);
129 static GstFlowReturn handle_pad_block (GstPad * pad);
130 static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
131 static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
132 static gboolean gst_pad_activate_default (GstPad * pad);
133 static gboolean gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps);
135 #if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
136 #ifdef GST_DISABLE_DEPRECATED
137 #include <libxml/parser.h>
139 static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
140 void gst_pad_load_and_link (xmlNodePtr self, GstObject * parent);
143 /* Some deprecated stuff that we need inside here for
144 * backwards compatibility */
145 #ifdef GST_DISABLE_DEPRECATED
146 #ifndef GST_REMOVE_DEPRECATED
147 #define GST_PAD_INTLINKFUNC(pad) (GST_PAD_CAST(pad)->intlinkfunc)
148 GList *gst_pad_get_internal_links_default (GstPad * pad);
152 static GstObjectClass *parent_class = NULL;
153 static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
155 static GParamSpec *pspec_caps = NULL;
157 /* quarks for probe signals */
158 static GQuark buffer_quark;
159 static GQuark event_quark;
168 static GstFlowQuarks flow_quarks[] = {
169 {GST_FLOW_CUSTOM_SUCCESS, "custom-success", 0},
170 {GST_FLOW_RESEND, "resend", 0},
171 {GST_FLOW_OK, "ok", 0},
172 {GST_FLOW_NOT_LINKED, "not-linked", 0},
173 {GST_FLOW_WRONG_STATE, "wrong-state", 0},
174 {GST_FLOW_UNEXPECTED, "unexpected", 0},
175 {GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
176 {GST_FLOW_ERROR, "error", 0},
177 {GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
178 {GST_FLOW_CUSTOM_ERROR, "custom-error", 0}
183 * @ret: a #GstFlowReturn to get the name of.
185 * Gets a string representing the given flow return.
187 * Returns: a static string with the name of the flow return.
190 gst_flow_get_name (GstFlowReturn ret)
194 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
196 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
197 if (ret == flow_quarks[i].ret)
198 return flow_quarks[i].name;
205 * @ret: a #GstFlowReturn to get the quark of.
207 * Get the unique quark for the given GstFlowReturn.
209 * Returns: the quark associated with the flow return or 0 if an
210 * invalid return was specified.
213 gst_flow_to_quark (GstFlowReturn ret)
217 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
219 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
220 if (ret == flow_quarks[i].ret)
221 return flow_quarks[i].quark;
230 buffer_quark = g_quark_from_static_string ("buffer"); \
231 event_quark = g_quark_from_static_string ("event"); \
233 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) { \
234 flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name); \
237 GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW", \
238 GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads"); \
241 G_DEFINE_TYPE_WITH_CODE (GstPad, gst_pad, GST_TYPE_OBJECT, _do_init);
244 _gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
245 GValue * return_accu, const GValue * handler_return, gpointer dummy)
247 gboolean ret = g_value_get_boolean (handler_return);
249 GST_DEBUG ("accumulated %d", ret);
250 g_value_set_boolean (return_accu, ret);
256 default_have_data (GstPad * pad, GstMiniObject * o)
262 gst_pad_class_init (GstPadClass * klass)
264 GObjectClass *gobject_class;
265 GstObjectClass *gstobject_class;
267 gobject_class = G_OBJECT_CLASS (klass);
268 gstobject_class = GST_OBJECT_CLASS (klass);
270 g_type_class_add_private (klass, sizeof (GstPadPrivate));
272 parent_class = g_type_class_peek_parent (klass);
274 gobject_class->dispose = gst_pad_dispose;
275 gobject_class->finalize = gst_pad_finalize;
276 gobject_class->set_property = gst_pad_set_property;
277 gobject_class->get_property = gst_pad_get_property;
281 * @pad: the pad that emitted the signal
282 * @peer: the peer pad that has been connected
284 * Signals that a pad has been linked to the peer pad.
286 gst_pad_signals[PAD_LINKED] =
287 g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
288 G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
289 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
292 * @pad: the pad that emitted the signal
293 * @peer: the peer pad that has been disconnected
295 * Signals that a pad has been unlinked from the peer pad.
297 gst_pad_signals[PAD_UNLINKED] =
298 g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
299 G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
300 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
302 * GstPad::request-link:
303 * @pad: the pad that emitted the signal
304 * @peer: the peer pad for which a connection is requested
306 * Signals that a pad connection has been requested.
308 gst_pad_signals[PAD_REQUEST_LINK] =
309 g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
310 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
311 NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
315 * @pad: the pad that emitted the signal
316 * @mini_obj: new data
318 * Signals that new data is available on the pad. This signal is used
319 * internally for implementing pad probes.
320 * See gst_pad_add_*_probe functions.
322 * Returns: %TRUE to keep the data, %FALSE to drop it
324 gst_pad_signals[PAD_HAVE_DATA] =
325 g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
326 G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
327 G_STRUCT_OFFSET (GstPadClass, have_data),
328 _gst_do_pass_data_accumulator,
329 NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
330 GST_TYPE_MINI_OBJECT);
332 pspec_caps = g_param_spec_boxed ("caps", "Caps",
333 "The capabilities of the pad", GST_TYPE_CAPS,
334 G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
335 g_object_class_install_property (gobject_class, PAD_PROP_CAPS, pspec_caps);
337 g_object_class_install_property (gobject_class, PAD_PROP_DIRECTION,
338 g_param_spec_enum ("direction", "Direction", "The direction of the pad",
339 GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
340 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
341 /* FIXME, Make G_PARAM_CONSTRUCT_ONLY when we fix ghostpads. */
342 g_object_class_install_property (gobject_class, PAD_PROP_TEMPLATE,
343 g_param_spec_object ("template", "Template",
344 "The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
345 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
347 #if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
348 gstobject_class->save_thyself =
349 ((gpointer (*)(GstObject * object,
350 gpointer self)) * GST_DEBUG_FUNCPTR (gst_pad_save_thyself));
352 gstobject_class->path_string_separator = ".";
354 /* Register common function pointer descriptions */
355 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_activate_default);
356 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_event_default);
357 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_query_types_default);
358 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_query_default);
359 #ifndef GST_REMOVE_DEPRECATED
360 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_internal_links_default);
362 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_iterate_internal_links_default);
363 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_acceptcaps_default);
365 /* from gstutils.c */
366 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_fixed_caps_func);
368 klass->have_data = default_have_data;
372 gst_pad_init (GstPad * pad)
374 pad->abidata.ABI.priv = GST_PAD_GET_PRIVATE (pad);
376 GST_PAD_DIRECTION (pad) = GST_PAD_UNKNOWN;
377 GST_PAD_PEER (pad) = NULL;
379 GST_PAD_CHAINFUNC (pad) = NULL;
381 GST_PAD_LINKFUNC (pad) = NULL;
383 GST_PAD_CAPS (pad) = NULL;
384 GST_PAD_GETCAPSFUNC (pad) = NULL;
386 GST_PAD_ACTIVATEFUNC (pad) = gst_pad_activate_default;
387 GST_PAD_EVENTFUNC (pad) = gst_pad_event_default;
388 GST_PAD_QUERYTYPEFUNC (pad) = gst_pad_get_query_types_default;
389 GST_PAD_QUERYFUNC (pad) = gst_pad_query_default;
390 #ifndef GST_REMOVE_DEPRECATED
391 GST_PAD_INTLINKFUNC (pad) = gst_pad_get_internal_links_default;
393 GST_PAD_ITERINTLINKFUNC (pad) = gst_pad_iterate_internal_links_default;
395 GST_PAD_ACCEPTCAPSFUNC (pad) = gst_pad_acceptcaps_default;
397 pad->do_buffer_signals = 0;
398 pad->do_event_signals = 0;
400 GST_PAD_SET_FLUSHING (pad);
402 pad->preroll_lock = g_mutex_new ();
403 pad->preroll_cond = g_cond_new ();
405 /* FIXME 0.11: Store this directly in the instance struct */
406 pad->stream_rec_lock = g_slice_new (GStaticRecMutex);
407 g_static_rec_mutex_init (pad->stream_rec_lock);
409 pad->block_cond = g_cond_new ();
413 gst_pad_dispose (GObject * object)
415 GstPad *pad = GST_PAD_CAST (object);
418 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pad, "dispose");
420 /* unlink the peer pad */
421 if ((peer = gst_pad_get_peer (pad))) {
422 /* window for MT unsafeness, someone else could unlink here
423 * and then we call unlink with wrong pads. The unlink
424 * function would catch this and safely return failed. */
425 if (GST_PAD_IS_SRC (pad))
426 gst_pad_unlink (pad, peer);
428 gst_pad_unlink (peer, pad);
430 gst_object_unref (peer);
434 gst_caps_replace (&GST_PAD_CAPS (pad), NULL);
436 gst_pad_set_pad_template (pad, NULL);
438 if (pad->block_destroy_data && pad->block_data) {
439 pad->block_destroy_data (pad->block_data);
440 pad->block_data = NULL;
443 G_OBJECT_CLASS (parent_class)->dispose (object);
447 gst_pad_finalize (GObject * object)
449 GstPad *pad = GST_PAD_CAST (object);
452 /* in case the task is still around, clean it up */
453 if ((task = GST_PAD_TASK (pad))) {
454 gst_task_join (task);
455 GST_PAD_TASK (pad) = NULL;
456 gst_object_unref (task);
459 if (pad->stream_rec_lock) {
460 g_static_rec_mutex_free (pad->stream_rec_lock);
461 g_slice_free (GStaticRecMutex, pad->stream_rec_lock);
462 pad->stream_rec_lock = NULL;
464 if (pad->preroll_lock) {
465 g_mutex_free (pad->preroll_lock);
466 g_cond_free (pad->preroll_cond);
467 pad->preroll_lock = NULL;
468 pad->preroll_cond = NULL;
470 if (pad->block_cond) {
471 g_cond_free (pad->block_cond);
472 pad->block_cond = NULL;
475 G_OBJECT_CLASS (parent_class)->finalize (object);
479 gst_pad_set_property (GObject * object, guint prop_id,
480 const GValue * value, GParamSpec * pspec)
482 g_return_if_fail (GST_IS_PAD (object));
485 case PAD_PROP_DIRECTION:
486 GST_PAD_DIRECTION (object) = (GstPadDirection) g_value_get_enum (value);
488 case PAD_PROP_TEMPLATE:
489 gst_pad_set_pad_template (GST_PAD_CAST (object),
490 (GstPadTemplate *) g_value_get_object (value));
493 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
499 gst_pad_get_property (GObject * object, guint prop_id,
500 GValue * value, GParamSpec * pspec)
502 g_return_if_fail (GST_IS_PAD (object));
506 GST_OBJECT_LOCK (object);
507 g_value_set_boxed (value, GST_PAD_CAPS (object));
508 GST_OBJECT_UNLOCK (object);
510 case PAD_PROP_DIRECTION:
511 g_value_set_enum (value, GST_PAD_DIRECTION (object));
513 case PAD_PROP_TEMPLATE:
514 g_value_set_object (value, GST_PAD_PAD_TEMPLATE (object));
517 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
524 * @name: the name of the new pad.
525 * @direction: the #GstPadDirection of the pad.
527 * Creates a new pad with the given name in the given direction.
528 * If name is NULL, a guaranteed unique name (across all pads)
530 * This function makes a copy of the name so you can safely free the name.
532 * Returns: (transfer full): a new #GstPad, or NULL in case of an error.
537 gst_pad_new (const gchar * name, GstPadDirection direction)
539 return g_object_new (GST_TYPE_PAD,
540 "name", name, "direction", direction, NULL);
544 * gst_pad_new_from_template:
545 * @templ: the pad template to use
546 * @name: the name of the element
548 * Creates a new pad with the given name from the given template.
549 * If name is NULL, a guaranteed unique name (across all pads)
551 * This function makes a copy of the name so you can safely free the name.
553 * Returns: (transfer full): a new #GstPad, or NULL in case of an error.
556 gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
558 g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
560 return g_object_new (GST_TYPE_PAD,
561 "name", name, "direction", templ->direction, "template", templ, NULL);
565 * gst_pad_new_from_static_template:
566 * @templ: the #GstStaticPadTemplate to use
567 * @name: the name of the element
569 * Creates a new pad with the given name from the given static template.
570 * If name is NULL, a guaranteed unique name (across all pads)
572 * This function makes a copy of the name so you can safely free the name.
574 * Returns: (transfer full): a new #GstPad, or NULL in case of an error.
577 gst_pad_new_from_static_template (GstStaticPadTemplate * templ,
581 GstPadTemplate *template;
583 template = gst_static_pad_template_get (templ);
584 pad = gst_pad_new_from_template (template, name);
585 gst_object_unref (template);
590 * gst_pad_get_direction:
591 * @pad: a #GstPad to get the direction of.
593 * Gets the direction of the pad. The direction of the pad is
594 * decided at construction time so this function does not take
597 * Returns: the #GstPadDirection of the pad.
602 gst_pad_get_direction (GstPad * pad)
604 GstPadDirection result;
606 /* PAD_UNKNOWN is a little silly but we need some sort of
607 * error return value */
608 g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
610 result = GST_PAD_DIRECTION (pad);
616 gst_pad_activate_default (GstPad * pad)
618 return gst_pad_activate_push (pad, TRUE);
622 pre_activate (GstPad * pad, GstActivateMode new_mode)
625 case GST_ACTIVATE_PUSH:
626 case GST_ACTIVATE_PULL:
627 GST_OBJECT_LOCK (pad);
628 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE %d, unset flushing",
630 GST_PAD_UNSET_FLUSHING (pad);
631 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
632 GST_OBJECT_UNLOCK (pad);
634 case GST_ACTIVATE_NONE:
635 GST_OBJECT_LOCK (pad);
636 GST_DEBUG_OBJECT (pad, "setting ACTIVATE_MODE NONE, set flushing");
637 _priv_gst_pad_invalidate_cache (pad);
638 GST_PAD_SET_FLUSHING (pad);
639 GST_PAD_ACTIVATE_MODE (pad) = new_mode;
640 /* unlock blocked pads so element can resume and stop */
641 GST_PAD_BLOCK_BROADCAST (pad);
642 GST_OBJECT_UNLOCK (pad);
648 post_activate (GstPad * pad, GstActivateMode new_mode)
651 case GST_ACTIVATE_PUSH:
652 case GST_ACTIVATE_PULL:
655 case GST_ACTIVATE_NONE:
656 /* ensures that streaming stops */
657 GST_PAD_STREAM_LOCK (pad);
658 GST_DEBUG_OBJECT (pad, "stopped streaming");
659 GST_PAD_STREAM_UNLOCK (pad);
665 * gst_pad_set_active:
666 * @pad: the #GstPad to activate or deactivate.
667 * @active: whether or not the pad should be active.
669 * Activates or deactivates the given pad.
670 * Normally called from within core state change functions.
672 * If @active, makes sure the pad is active. If it is already active, either in
673 * push or pull mode, just return. Otherwise dispatches to the pad's activate
674 * function to perform the actual activation.
676 * If not @active, checks the pad's current mode and calls
677 * gst_pad_activate_push() or gst_pad_activate_pull(), as appropriate, with a
680 * Returns: #TRUE if the operation was successful.
685 gst_pad_set_active (GstPad * pad, gboolean active)
688 gboolean ret = FALSE;
690 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
692 GST_OBJECT_LOCK (pad);
693 old = GST_PAD_ACTIVATE_MODE (pad);
694 GST_OBJECT_UNLOCK (pad);
698 case GST_ACTIVATE_PUSH:
699 GST_DEBUG_OBJECT (pad, "activating pad from push");
702 case GST_ACTIVATE_PULL:
703 GST_DEBUG_OBJECT (pad, "activating pad from pull");
706 case GST_ACTIVATE_NONE:
707 GST_DEBUG_OBJECT (pad, "activating pad from none");
708 ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad);
713 case GST_ACTIVATE_PUSH:
714 GST_DEBUG_OBJECT (pad, "deactivating pad from push");
715 ret = gst_pad_activate_push (pad, FALSE);
717 case GST_ACTIVATE_PULL:
718 GST_DEBUG_OBJECT (pad, "deactivating pad from pull");
719 ret = gst_pad_activate_pull (pad, FALSE);
721 case GST_ACTIVATE_NONE:
722 GST_DEBUG_OBJECT (pad, "deactivating pad from none");
729 GST_OBJECT_LOCK (pad);
731 g_critical ("Failed to deactivate pad %s:%s, very bad",
732 GST_DEBUG_PAD_NAME (pad));
734 GST_WARNING_OBJECT (pad, "Failed to activate pad");
736 GST_OBJECT_UNLOCK (pad);
743 * gst_pad_activate_pull:
744 * @pad: the #GstPad to activate or deactivate.
745 * @active: whether or not the pad should be active.
747 * Activates or deactivates the given pad in pull mode via dispatching to the
748 * pad's activatepullfunc. For use from within pad activation functions only.
749 * When called on sink pads, will first proxy the call to the peer pad, which
750 * is expected to activate its internally linked pads from within its
751 * activate_pull function.
753 * If you don't know what this is, you probably don't want to call it.
755 * Returns: TRUE if the operation was successful.
760 gst_pad_activate_pull (GstPad * pad, gboolean active)
762 GstActivateMode old, new;
765 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
767 GST_OBJECT_LOCK (pad);
768 old = GST_PAD_ACTIVATE_MODE (pad);
769 GST_OBJECT_UNLOCK (pad);
773 case GST_ACTIVATE_PULL:
774 GST_DEBUG_OBJECT (pad, "activating pad from pull, was ok");
776 case GST_ACTIVATE_PUSH:
777 GST_DEBUG_OBJECT (pad,
778 "activating pad from push, deactivate push first");
779 /* pad was activate in the wrong direction, deactivate it
780 * and reactivate it in pull mode */
781 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
782 goto deactivate_failed;
783 /* fallthrough, pad is deactivated now. */
784 case GST_ACTIVATE_NONE:
785 GST_DEBUG_OBJECT (pad, "activating pad from none");
790 case GST_ACTIVATE_NONE:
791 GST_DEBUG_OBJECT (pad, "deactivating pad from none, was ok");
793 case GST_ACTIVATE_PUSH:
794 GST_DEBUG_OBJECT (pad, "deactivating pad from push, weird");
795 /* pad was activated in the other direction, deactivate it
796 * in push mode, this should not happen... */
797 if (G_UNLIKELY (!gst_pad_activate_push (pad, FALSE)))
798 goto deactivate_failed;
799 /* everything is fine now */
801 case GST_ACTIVATE_PULL:
802 GST_DEBUG_OBJECT (pad, "deactivating pad from pull");
807 if (gst_pad_get_direction (pad) == GST_PAD_SINK) {
808 if ((peer = gst_pad_get_peer (pad))) {
809 GST_DEBUG_OBJECT (pad, "calling peer");
810 if (G_UNLIKELY (!gst_pad_activate_pull (peer, active)))
812 gst_object_unref (peer);
814 /* there is no peer, this is only fatal when we activate. When we
815 * deactivate, we must assume the application has unlinked the peer and
816 * will deactivate it eventually. */
820 GST_DEBUG_OBJECT (pad, "deactivating unlinked pad");
823 if (G_UNLIKELY (GST_PAD_GETRANGEFUNC (pad) == NULL))
824 goto failure; /* Can't activate pull on a src without a
828 new = active ? GST_ACTIVATE_PULL : GST_ACTIVATE_NONE;
829 pre_activate (pad, new);
831 if (GST_PAD_ACTIVATEPULLFUNC (pad)) {
832 if (G_UNLIKELY (!GST_PAD_ACTIVATEPULLFUNC (pad) (pad, active)))
835 /* can happen for sinks of passthrough elements */
838 post_activate (pad, new);
840 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in pull mode",
841 active ? "activated" : "deactivated");
847 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in pull mode",
848 active ? "activated" : "deactivated");
853 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
854 "failed to %s in switch to pull from mode %d",
855 (active ? "activate" : "deactivate"), old);
860 GST_OBJECT_LOCK (peer);
861 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
862 "activate_pull on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
863 GST_OBJECT_UNLOCK (peer);
864 gst_object_unref (peer);
869 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "can't activate unlinked sink "
875 GST_OBJECT_LOCK (pad);
876 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in pull mode",
877 active ? "activate" : "deactivate");
878 _priv_gst_pad_invalidate_cache (pad);
879 GST_PAD_SET_FLUSHING (pad);
880 GST_PAD_ACTIVATE_MODE (pad) = old;
881 GST_OBJECT_UNLOCK (pad);
887 * gst_pad_activate_push:
888 * @pad: the #GstPad to activate or deactivate.
889 * @active: whether the pad should be active or not.
891 * Activates or deactivates the given pad in push mode via dispatching to the
892 * pad's activatepushfunc. For use from within pad activation functions only.
894 * If you don't know what this is, you probably don't want to call it.
896 * Returns: %TRUE if the operation was successful.
901 gst_pad_activate_push (GstPad * pad, gboolean active)
903 GstActivateMode old, new;
905 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
906 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "trying to set %s in push mode",
907 active ? "activated" : "deactivated");
909 GST_OBJECT_LOCK (pad);
910 old = GST_PAD_ACTIVATE_MODE (pad);
911 GST_OBJECT_UNLOCK (pad);
915 case GST_ACTIVATE_PUSH:
916 GST_DEBUG_OBJECT (pad, "activating pad from push, was ok");
918 case GST_ACTIVATE_PULL:
919 GST_DEBUG_OBJECT (pad,
920 "activating pad from push, deactivating pull first");
921 /* pad was activate in the wrong direction, deactivate it
922 * an reactivate it in push mode */
923 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
924 goto deactivate_failed;
925 /* fallthrough, pad is deactivated now. */
926 case GST_ACTIVATE_NONE:
927 GST_DEBUG_OBJECT (pad, "activating pad from none");
932 case GST_ACTIVATE_NONE:
933 GST_DEBUG_OBJECT (pad, "deactivating pad from none, was ok");
935 case GST_ACTIVATE_PULL:
936 GST_DEBUG_OBJECT (pad, "deactivating pad from pull, weird");
937 /* pad was activated in the other direction, deactivate it
938 * in pull mode, this should not happen... */
939 if (G_UNLIKELY (!gst_pad_activate_pull (pad, FALSE)))
940 goto deactivate_failed;
941 /* everything is fine now */
943 case GST_ACTIVATE_PUSH:
944 GST_DEBUG_OBJECT (pad, "deactivating pad from push");
949 new = active ? GST_ACTIVATE_PUSH : GST_ACTIVATE_NONE;
950 pre_activate (pad, new);
952 if (GST_PAD_ACTIVATEPUSHFUNC (pad)) {
953 if (G_UNLIKELY (!GST_PAD_ACTIVATEPUSHFUNC (pad) (pad, active))) {
957 /* quite ok, element relies on state change func to prepare itself */
960 post_activate (pad, new);
962 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in push mode",
963 active ? "activated" : "deactivated");
968 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in push mode",
969 active ? "activated" : "deactivated");
974 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
975 "failed to %s in switch to push from mode %d",
976 (active ? "activate" : "deactivate"), old);
981 GST_OBJECT_LOCK (pad);
982 GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in push mode",
983 active ? "activate" : "deactivate");
984 _priv_gst_pad_invalidate_cache (pad);
985 GST_PAD_SET_FLUSHING (pad);
986 GST_PAD_ACTIVATE_MODE (pad) = old;
987 GST_OBJECT_UNLOCK (pad);
994 * @pad: the #GstPad to query
996 * Query if a pad is active
998 * Returns: TRUE if the pad is active.
1003 gst_pad_is_active (GstPad * pad)
1005 gboolean result = FALSE;
1007 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1009 GST_OBJECT_LOCK (pad);
1010 result = GST_PAD_MODE_ACTIVATE (GST_PAD_ACTIVATE_MODE (pad));
1011 GST_OBJECT_UNLOCK (pad);
1017 * gst_pad_set_blocked_async_full:
1018 * @pad: the #GstPad to block or unblock
1019 * @blocked: boolean indicating whether the pad should be blocked or unblocked
1020 * @callback: #GstPadBlockCallback that will be called when the
1021 * operation succeeds
1022 * @user_data: (closure): user data passed to the callback
1023 * @destroy_data: #GDestroyNotify for user_data
1025 * Blocks or unblocks the dataflow on a pad. The provided callback
1026 * is called when the operation succeeds; this happens right before the next
1027 * attempt at pushing a buffer on the pad.
1029 * This can take a while as the pad can only become blocked when real dataflow
1031 * When the pipeline is stalled, for example in PAUSED, this can
1032 * take an indeterminate amount of time.
1033 * You can pass NULL as the callback to make this call block. Be careful with
1034 * this blocking call as it might not return for reasons stated above.
1037 * Pad block handlers are only called for source pads in push mode
1038 * and sink pads in pull mode.
1041 * Returns: %TRUE if the pad could be blocked. This function can fail if the
1042 * wrong parameters were passed or the pad was already in the requested state.
1049 gst_pad_set_blocked_async_full (GstPad * pad, gboolean blocked,
1050 GstPadBlockCallback callback, gpointer user_data,
1051 GDestroyNotify destroy_data)
1053 gboolean was_blocked = FALSE;
1055 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1057 GST_OBJECT_LOCK (pad);
1059 was_blocked = GST_PAD_IS_BLOCKED (pad);
1061 if (G_UNLIKELY (was_blocked == blocked))
1062 goto had_right_state;
1065 (GST_PAD_ACTIVATE_MODE (pad) == GST_ACTIVATE_PUSH) &&
1066 (GST_PAD_DIRECTION (pad) != GST_PAD_SRC)))
1067 goto wrong_direction;
1069 (GST_PAD_ACTIVATE_MODE (pad) == GST_ACTIVATE_PULL) &&
1070 (GST_PAD_DIRECTION (pad) != GST_PAD_SINK)))
1071 goto wrong_direction;
1074 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
1076 _priv_gst_pad_invalidate_cache (pad);
1077 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
1079 if (pad->block_destroy_data && pad->block_data)
1080 pad->block_destroy_data (pad->block_data);
1082 pad->block_callback = callback;
1083 pad->block_data = user_data;
1084 pad->block_destroy_data = destroy_data;
1085 pad->abidata.ABI.block_callback_called = FALSE;
1087 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
1088 GST_PAD_BLOCK_WAIT (pad);
1089 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
1092 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
1094 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
1096 if (pad->block_destroy_data && pad->block_data)
1097 pad->block_destroy_data (pad->block_data);
1099 pad->block_callback = callback;
1100 pad->block_data = user_data;
1101 pad->block_destroy_data = destroy_data;
1102 pad->abidata.ABI.block_callback_called = FALSE;
1104 GST_PAD_BLOCK_BROADCAST (pad);
1106 /* no callback, wait for the unblock to happen */
1107 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
1108 GST_PAD_BLOCK_WAIT (pad);
1109 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
1112 GST_OBJECT_UNLOCK (pad);
1120 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
1121 "pad was in right state (%d)", was_blocked);
1122 GST_OBJECT_UNLOCK (pad);
1128 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pad block on the wrong pad, "
1129 "block src pads in push mode and sink pads in pull mode.");
1130 GST_OBJECT_UNLOCK (pad);
1137 * gst_pad_set_blocked_async:
1138 * @pad: the #GstPad to block or unblock
1139 * @blocked: boolean indicating whether the pad should be blocked or unblocked
1140 * @callback: #GstPadBlockCallback that will be called when the
1141 * operation succeeds
1142 * @user_data: (closure): user data passed to the callback
1144 * Blocks or unblocks the dataflow on a pad. The provided callback
1145 * is called when the operation succeeds; this happens right before the next
1146 * attempt at pushing a buffer on the pad.
1148 * This can take a while as the pad can only become blocked when real dataflow
1150 * When the pipeline is stalled, for example in PAUSED, this can
1151 * take an indeterminate amount of time.
1152 * You can pass NULL as the callback to make this call block. Be careful with
1153 * this blocking call as it might not return for reasons stated above.
1156 * Pad block handlers are only called for source pads in push mode
1157 * and sink pads in pull mode.
1160 * Returns: TRUE if the pad could be blocked. This function can fail if the
1161 * wrong parameters were passed or the pad was already in the requested state.
1166 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
1167 GstPadBlockCallback callback, gpointer user_data)
1169 return gst_pad_set_blocked_async_full (pad, blocked,
1170 callback, user_data, NULL);
1174 * gst_pad_set_blocked:
1175 * @pad: the #GstPad to block or unblock
1176 * @blocked: boolean indicating we should block or unblock
1178 * Blocks or unblocks the dataflow on a pad. This function is
1179 * a shortcut for gst_pad_set_blocked_async() with a NULL
1183 * Pad blocks are only possible for source pads in push mode
1184 * and sink pads in pull mode.
1187 * Returns: TRUE if the pad could be blocked. This function can fail if the
1188 * wrong parameters were passed or the pad was already in the requested state.
1193 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
1195 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
1199 * gst_pad_is_blocked:
1200 * @pad: the #GstPad to query
1202 * Checks if the pad is blocked or not. This function returns the
1203 * last requested state of the pad. It is not certain that the pad
1204 * is actually blocking at this point (see gst_pad_is_blocking()).
1206 * Returns: TRUE if the pad is blocked.
1211 gst_pad_is_blocked (GstPad * pad)
1213 gboolean result = FALSE;
1215 g_return_val_if_fail (GST_IS_PAD (pad), result);
1217 GST_OBJECT_LOCK (pad);
1218 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
1219 GST_OBJECT_UNLOCK (pad);
1225 * gst_pad_is_blocking:
1226 * @pad: the #GstPad to query
1228 * Checks if the pad is blocking or not. This is a guaranteed state
1229 * of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
1231 * Returns: TRUE if the pad is blocking.
1238 gst_pad_is_blocking (GstPad * pad)
1240 gboolean result = FALSE;
1242 g_return_val_if_fail (GST_IS_PAD (pad), result);
1244 GST_OBJECT_LOCK (pad);
1245 /* the blocking flag is only valid if the pad is not flushing */
1246 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKING) &&
1247 !GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLUSHING);
1248 GST_OBJECT_UNLOCK (pad);
1254 * gst_pad_set_activate_function:
1256 * @activate: the #GstPadActivateFunction to set.
1258 * Sets the given activate function for @pad. The activate function will
1259 * dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
1260 * the actual activation. Only makes sense to set on sink pads.
1262 * Call this function if your sink pad can start a pull-based task.
1265 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
1267 g_return_if_fail (GST_IS_PAD (pad));
1269 GST_PAD_ACTIVATEFUNC (pad) = activate;
1270 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
1271 GST_DEBUG_FUNCPTR_NAME (activate));
1275 * gst_pad_set_activatepull_function:
1277 * @activatepull: the #GstPadActivateModeFunction to set.
1279 * Sets the given activate_pull function for the pad. An activate_pull function
1280 * prepares the element and any upstream connections for pulling. See XXX
1281 * part-activation.txt for details.
1284 gst_pad_set_activatepull_function (GstPad * pad,
1285 GstPadActivateModeFunction activatepull)
1287 g_return_if_fail (GST_IS_PAD (pad));
1289 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
1290 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
1291 GST_DEBUG_FUNCPTR_NAME (activatepull));
1295 * gst_pad_set_activatepush_function:
1297 * @activatepush: the #GstPadActivateModeFunction to set.
1299 * Sets the given activate_push function for the pad. An activate_push function
1300 * prepares the element for pushing. See XXX part-activation.txt for details.
1303 gst_pad_set_activatepush_function (GstPad * pad,
1304 GstPadActivateModeFunction activatepush)
1306 g_return_if_fail (GST_IS_PAD (pad));
1308 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1309 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
1310 GST_DEBUG_FUNCPTR_NAME (activatepush));
1314 * gst_pad_set_chain_function:
1315 * @pad: a sink #GstPad.
1316 * @chain: the #GstPadChainFunction to set.
1318 * Sets the given chain function for the pad. The chain function is called to
1319 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1322 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1324 g_return_if_fail (GST_IS_PAD (pad));
1325 g_return_if_fail (GST_PAD_IS_SINK (pad));
1327 GST_PAD_CHAINFUNC (pad) = chain;
1328 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
1329 GST_DEBUG_FUNCPTR_NAME (chain));
1333 * gst_pad_set_chain_list_function:
1334 * @pad: a sink #GstPad.
1335 * @chainlist: the #GstPadChainListFunction to set.
1337 * Sets the given chain list function for the pad. The chainlist function is
1338 * called to process a #GstBufferList input buffer list. See
1339 * #GstPadChainListFunction for more details.
1344 gst_pad_set_chain_list_function (GstPad * pad,
1345 GstPadChainListFunction chainlist)
1347 g_return_if_fail (GST_IS_PAD (pad));
1348 g_return_if_fail (GST_PAD_IS_SINK (pad));
1350 GST_PAD_CHAINLISTFUNC (pad) = chainlist;
1351 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainlistfunc set to %s",
1352 GST_DEBUG_FUNCPTR_NAME (chainlist));
1356 * gst_pad_set_getrange_function:
1357 * @pad: a source #GstPad.
1358 * @get: the #GstPadGetRangeFunction to set.
1360 * Sets the given getrange function for the pad. The getrange function is
1361 * called to produce a new #GstBuffer to start the processing pipeline. see
1362 * #GstPadGetRangeFunction for a description of the getrange function.
1365 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1367 g_return_if_fail (GST_IS_PAD (pad));
1368 g_return_if_fail (GST_PAD_IS_SRC (pad));
1370 GST_PAD_GETRANGEFUNC (pad) = get;
1372 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
1373 GST_DEBUG_FUNCPTR_NAME (get));
1377 * gst_pad_set_checkgetrange_function:
1378 * @pad: a source #GstPad.
1379 * @check: the #GstPadCheckGetRangeFunction to set.
1381 * Sets the given checkgetrange function for the pad. Implement this function
1382 * on a pad if you dynamically support getrange based scheduling on the pad.
1385 gst_pad_set_checkgetrange_function (GstPad * pad,
1386 GstPadCheckGetRangeFunction check)
1388 g_return_if_fail (GST_IS_PAD (pad));
1389 g_return_if_fail (GST_PAD_IS_SRC (pad));
1391 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1393 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
1394 GST_DEBUG_FUNCPTR_NAME (check));
1398 * gst_pad_set_event_function:
1399 * @pad: a #GstPad of either direction.
1400 * @event: the #GstPadEventFunction to set.
1402 * Sets the given event handler for the pad.
1405 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1407 g_return_if_fail (GST_IS_PAD (pad));
1409 GST_PAD_EVENTFUNC (pad) = event;
1411 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
1412 GST_DEBUG_FUNCPTR_NAME (event));
1416 * gst_pad_set_query_function:
1417 * @pad: a #GstPad of either direction.
1418 * @query: the #GstPadQueryFunction to set.
1420 * Set the given query function for the pad.
1423 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1425 g_return_if_fail (GST_IS_PAD (pad));
1427 GST_PAD_QUERYFUNC (pad) = query;
1429 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
1430 GST_DEBUG_FUNCPTR_NAME (query));
1434 * gst_pad_set_query_type_function:
1435 * @pad: a #GstPad of either direction.
1436 * @type_func: the #GstPadQueryTypeFunction to set.
1438 * Set the given query type function for the pad.
1441 gst_pad_set_query_type_function (GstPad * pad,
1442 GstPadQueryTypeFunction type_func)
1444 g_return_if_fail (GST_IS_PAD (pad));
1446 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1448 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
1449 GST_DEBUG_FUNCPTR_NAME (type_func));
1453 * gst_pad_get_query_types:
1456 * Get an array of supported queries that can be performed
1459 * Returns: (transfer none) (array zero-terminated=1): a zero-terminated array
1462 const GstQueryType *
1463 gst_pad_get_query_types (GstPad * pad)
1465 GstPadQueryTypeFunction func;
1467 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1469 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1481 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1483 *data = gst_pad_get_query_types (pad);
1489 * gst_pad_get_query_types_default:
1492 * Invoke the default dispatcher for the query types on
1495 * Returns: (transfer none) (array zero-terminated=1): a zero-terminated array
1496 * of #GstQueryType, or NULL if none of the internally-linked pads has a
1497 * query types function.
1499 const GstQueryType *
1500 gst_pad_get_query_types_default (GstPad * pad)
1502 GstQueryType *result = NULL;
1504 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1506 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1507 gst_pad_get_query_types_dispatcher, &result);
1513 * gst_pad_set_iterate_internal_links_function:
1514 * @pad: a #GstPad of either direction.
1515 * @iterintlink: the #GstPadIterIntLinkFunction to set.
1517 * Sets the given internal link iterator function for the pad.
1522 gst_pad_set_iterate_internal_links_function (GstPad * pad,
1523 GstPadIterIntLinkFunction iterintlink)
1525 g_return_if_fail (GST_IS_PAD (pad));
1527 GST_PAD_ITERINTLINKFUNC (pad) = iterintlink;
1528 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link iterator set to %s",
1529 GST_DEBUG_FUNCPTR_NAME (iterintlink));
1533 * gst_pad_set_internal_link_function:
1534 * @pad: a #GstPad of either direction.
1535 * @intlink: the #GstPadIntLinkFunction to set.
1537 * Sets the given internal link function for the pad.
1539 * Deprecated: Use the thread-safe gst_pad_set_iterate_internal_links_function()
1541 #ifndef GST_REMOVE_DEPRECATED
1542 #ifdef GST_DISABLE_DEPRECATED
1544 gst_pad_set_internal_link_function (GstPad * pad,
1545 GstPadIntLinkFunction intlink);
1548 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1550 g_return_if_fail (GST_IS_PAD (pad));
1552 GST_PAD_INTLINKFUNC (pad) = intlink;
1553 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
1554 GST_DEBUG_FUNCPTR_NAME (intlink));
1556 #endif /* GST_REMOVE_DEPRECATED */
1559 * gst_pad_set_link_function:
1561 * @link: the #GstPadLinkFunction to set.
1563 * Sets the given link function for the pad. It will be called when
1564 * the pad is linked with another pad.
1566 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1569 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1570 * cannot be made for some reason.
1572 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1573 * of the peer sink pad, if present.
1576 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1578 g_return_if_fail (GST_IS_PAD (pad));
1580 GST_PAD_LINKFUNC (pad) = link;
1581 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
1582 GST_DEBUG_FUNCPTR_NAME (link));
1586 * gst_pad_set_unlink_function:
1588 * @unlink: the #GstPadUnlinkFunction to set.
1590 * Sets the given unlink function for the pad. It will be called
1591 * when the pad is unlinked.
1594 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1596 g_return_if_fail (GST_IS_PAD (pad));
1598 GST_PAD_UNLINKFUNC (pad) = unlink;
1599 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
1600 GST_DEBUG_FUNCPTR_NAME (unlink));
1604 * gst_pad_set_getcaps_function:
1606 * @getcaps: the #GstPadGetCapsFunction to set.
1608 * Sets the given getcaps function for the pad. @getcaps should return the
1609 * allowable caps for a pad in the context of the element's state, its link to
1610 * other elements, and the devices or files it has opened. These caps must be a
1611 * subset of the pad template caps. In the NULL state with no links, @getcaps
1612 * should ideally return the same caps as the pad template. In rare
1613 * circumstances, an object property can affect the caps returned by @getcaps,
1614 * but this is discouraged.
1616 * You do not need to call this function if @pad's allowed caps are always the
1617 * same as the pad template caps. This can only be true if the padtemplate
1618 * has fixed simple caps.
1620 * For most filters, the caps returned by @getcaps is directly affected by the
1621 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1622 * the srcpad's getcaps function is directly related to the stream data. Again,
1623 * @getcaps should return the most specific caps it reasonably can, since this
1624 * helps with autoplugging.
1626 * Note that the return value from @getcaps is owned by the caller, so the
1627 * caller should unref the caps after usage.
1630 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1632 g_return_if_fail (GST_IS_PAD (pad));
1634 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1635 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
1636 GST_DEBUG_FUNCPTR_NAME (getcaps));
1640 * gst_pad_set_acceptcaps_function:
1642 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1644 * Sets the given acceptcaps function for the pad. The acceptcaps function
1645 * will be called to check if the pad can accept the given caps. Setting the
1646 * acceptcaps function to NULL restores the default behaviour of allowing
1647 * any caps that matches the caps from gst_pad_get_caps().
1650 gst_pad_set_acceptcaps_function (GstPad * pad,
1651 GstPadAcceptCapsFunction acceptcaps)
1653 g_return_if_fail (GST_IS_PAD (pad));
1655 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1656 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
1657 GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1661 * gst_pad_set_fixatecaps_function:
1663 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1665 * Sets the given fixatecaps function for the pad. The fixatecaps function
1666 * will be called whenever the default values for a GstCaps needs to be
1670 gst_pad_set_fixatecaps_function (GstPad * pad,
1671 GstPadFixateCapsFunction fixatecaps)
1673 g_return_if_fail (GST_IS_PAD (pad));
1675 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1676 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
1677 GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1681 * gst_pad_set_setcaps_function:
1683 * @setcaps: the #GstPadSetCapsFunction to set.
1685 * Sets the given setcaps function for the pad. The setcaps function
1686 * will be called whenever a buffer with a new media type is pushed or
1687 * pulled from the pad. The pad/element needs to update its internal
1688 * structures to process the new media type. If this new type is not
1689 * acceptable, the setcaps function should return FALSE.
1692 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1694 g_return_if_fail (GST_IS_PAD (pad));
1696 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1697 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
1698 GST_DEBUG_FUNCPTR_NAME (setcaps));
1702 * gst_pad_set_bufferalloc_function:
1703 * @pad: a sink #GstPad.
1704 * @bufalloc: the #GstPadBufferAllocFunction to set.
1706 * Sets the given bufferalloc function for the pad. Note that the
1707 * bufferalloc function can only be set on sinkpads.
1710 gst_pad_set_bufferalloc_function (GstPad * pad,
1711 GstPadBufferAllocFunction bufalloc)
1713 g_return_if_fail (GST_IS_PAD (pad));
1714 g_return_if_fail (GST_PAD_IS_SINK (pad));
1716 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1717 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
1718 GST_DEBUG_FUNCPTR_NAME (bufalloc));
1723 * @srcpad: the source #GstPad to unlink.
1724 * @sinkpad: the sink #GstPad to unlink.
1726 * Unlinks the source pad from the sink pad. Will emit the #GstPad::unlinked
1727 * signal on both pads.
1729 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1730 * the pads were not linked together.
1735 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1737 gboolean result = FALSE;
1738 GstElement *parent = NULL;
1740 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1741 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), FALSE);
1742 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1743 g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad), FALSE);
1745 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1746 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1747 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1749 /* We need to notify the parent before taking any pad locks as the bin in
1750 * question might be waiting for a lock on the pad while holding its lock
1751 * that our message will try to take. */
1752 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
1753 if (GST_IS_ELEMENT (parent)) {
1754 gst_element_post_message (parent,
1755 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
1756 GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, TRUE));
1758 gst_object_unref (parent);
1763 GST_OBJECT_LOCK (srcpad);
1765 GST_OBJECT_LOCK (sinkpad);
1767 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1768 goto not_linked_together;
1770 if (GST_PAD_UNLINKFUNC (srcpad)) {
1771 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1773 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1774 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1777 _priv_gst_pad_invalidate_cache (srcpad);
1779 /* first clear peers */
1780 GST_PAD_PEER (srcpad) = NULL;
1781 GST_PAD_PEER (sinkpad) = NULL;
1783 GST_OBJECT_UNLOCK (sinkpad);
1784 GST_OBJECT_UNLOCK (srcpad);
1786 /* fire off a signal to each of the pads telling them
1787 * that they've been unlinked */
1788 g_signal_emit (srcpad, gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1789 g_signal_emit (sinkpad, gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1791 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1792 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1797 if (parent != NULL) {
1798 gst_element_post_message (parent,
1799 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
1800 GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, FALSE));
1801 gst_object_unref (parent);
1806 not_linked_together:
1808 /* we do not emit a warning in this case because unlinking cannot
1809 * be made MT safe.*/
1810 GST_OBJECT_UNLOCK (sinkpad);
1811 GST_OBJECT_UNLOCK (srcpad);
1817 * gst_pad_is_linked:
1818 * @pad: pad to check
1820 * Checks if a @pad is linked to another pad or not.
1822 * Returns: TRUE if the pad is linked, FALSE otherwise.
1827 gst_pad_is_linked (GstPad * pad)
1831 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1833 GST_OBJECT_LOCK (pad);
1834 result = (GST_PAD_PEER (pad) != NULL);
1835 GST_OBJECT_UNLOCK (pad);
1840 /* get the caps from both pads and see if the intersection
1843 * This function should be called with the pad LOCK on both
1847 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink,
1848 GstPadLinkCheck flags)
1850 GstCaps *srccaps = NULL;
1851 GstCaps *sinkcaps = NULL;
1852 gboolean compatible = FALSE;
1854 if (!(flags & (GST_PAD_LINK_CHECK_CAPS | GST_PAD_LINK_CHECK_TEMPLATE_CAPS)))
1857 /* Doing the expensive caps checking takes priority over only checking the template caps */
1858 if (flags & GST_PAD_LINK_CHECK_CAPS) {
1859 srccaps = gst_pad_get_caps_unlocked (src);
1860 sinkcaps = gst_pad_get_caps_unlocked (sink);
1862 /* If one of the two pads doesn't have a template, consider the intersection
1864 if (G_UNLIKELY ((GST_PAD_PAD_TEMPLATE (src) == NULL)
1865 || (GST_PAD_PAD_TEMPLATE (sink) == NULL))) {
1869 srccaps = gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (src)));
1871 gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (sink)));
1874 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, src, "src caps %" GST_PTR_FORMAT,
1876 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, sink, "sink caps %" GST_PTR_FORMAT,
1879 /* if we have caps on both pads we can check the intersection. If one
1880 * of the caps is NULL, we return TRUE. */
1881 if (G_UNLIKELY (srccaps == NULL || sinkcaps == NULL)) {
1883 gst_caps_unref (srccaps);
1885 gst_caps_unref (sinkcaps);
1889 compatible = gst_caps_can_intersect (srccaps, sinkcaps);
1890 gst_caps_unref (srccaps);
1891 gst_caps_unref (sinkcaps);
1894 GST_CAT_DEBUG (GST_CAT_CAPS, "caps are %scompatible",
1895 (compatible ? "" : "not"));
1900 /* check if the grandparents of both pads are the same.
1901 * This check is required so that we don't try to link
1902 * pads from elements in different bins without ghostpads.
1904 * The LOCK should be held on both pads
1907 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1909 GstObject *psrc, *psink;
1911 psrc = GST_OBJECT_PARENT (src);
1912 psink = GST_OBJECT_PARENT (sink);
1914 /* if one of the pads has no parent, we allow the link */
1915 if (G_UNLIKELY (psrc == NULL || psink == NULL))
1918 /* only care about parents that are elements */
1919 if (G_UNLIKELY (!GST_IS_ELEMENT (psrc) || !GST_IS_ELEMENT (psink)))
1920 goto no_element_parent;
1922 /* if the parents are the same, we have a loop */
1923 if (G_UNLIKELY (psrc == psink))
1926 /* if they both have a parent, we check the grandparents. We can not lock
1927 * the parent because we hold on the child (pad) and the locking order is
1928 * parent >> child. */
1929 psrc = GST_OBJECT_PARENT (psrc);
1930 psink = GST_OBJECT_PARENT (psink);
1932 /* if they have grandparents but they are not the same */
1933 if (G_UNLIKELY (psrc != psink))
1934 goto wrong_grandparents;
1941 GST_CAT_DEBUG (GST_CAT_CAPS,
1942 "one of the pads has no parent %" GST_PTR_FORMAT " and %"
1943 GST_PTR_FORMAT, psrc, psink);
1948 GST_CAT_DEBUG (GST_CAT_CAPS,
1949 "one of the pads has no element parent %" GST_PTR_FORMAT " and %"
1950 GST_PTR_FORMAT, psrc, psink);
1955 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1961 GST_CAT_DEBUG (GST_CAT_CAPS,
1962 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1963 GST_PTR_FORMAT, psrc, psink);
1968 /* FIXME leftover from an attempt at refactoring... */
1969 /* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
1970 * the two pads will be locked in the srcpad, sinkpad order. */
1971 static GstPadLinkReturn
1972 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad, GstPadLinkCheck flags)
1974 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1975 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1977 GST_OBJECT_LOCK (srcpad);
1979 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1980 goto src_was_linked;
1982 GST_OBJECT_LOCK (sinkpad);
1984 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1985 goto sink_was_linked;
1987 /* check hierarchy, pads can only be linked if the grandparents
1989 if ((flags & GST_PAD_LINK_CHECK_HIERARCHY)
1990 && !gst_pad_link_check_hierarchy (srcpad, sinkpad))
1991 goto wrong_hierarchy;
1993 /* check pad caps for non-empty intersection */
1994 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad, flags))
1997 /* FIXME check pad scheduling for non-empty intersection */
1999 return GST_PAD_LINK_OK;
2003 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
2004 GST_DEBUG_PAD_NAME (srcpad),
2005 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
2006 /* we do not emit a warning in this case because unlinking cannot
2007 * be made MT safe.*/
2008 GST_OBJECT_UNLOCK (srcpad);
2009 return GST_PAD_LINK_WAS_LINKED;
2013 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
2014 GST_DEBUG_PAD_NAME (sinkpad),
2015 GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
2016 /* we do not emit a warning in this case because unlinking cannot
2017 * be made MT safe.*/
2018 GST_OBJECT_UNLOCK (sinkpad);
2019 GST_OBJECT_UNLOCK (srcpad);
2020 return GST_PAD_LINK_WAS_LINKED;
2024 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
2025 GST_OBJECT_UNLOCK (sinkpad);
2026 GST_OBJECT_UNLOCK (srcpad);
2027 return GST_PAD_LINK_WRONG_HIERARCHY;
2031 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
2032 GST_OBJECT_UNLOCK (sinkpad);
2033 GST_OBJECT_UNLOCK (srcpad);
2034 return GST_PAD_LINK_NOFORMAT;
2040 * @srcpad: the source #GstPad.
2041 * @sinkpad: the sink #GstPad.
2043 * Checks if the source pad and the sink pad are compatible so they can be
2046 * Returns: TRUE if the pads can be linked.
2049 gst_pad_can_link (GstPad * srcpad, GstPad * sinkpad)
2051 GstPadLinkReturn result;
2053 /* generic checks */
2054 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
2055 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
2057 GST_CAT_INFO (GST_CAT_PADS, "check if %s:%s can link with %s:%s",
2058 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2060 /* gst_pad_link_prepare does everything for us, we only release the locks
2061 * on the pads that it gets us. If this function returns !OK the locks are not
2063 result = gst_pad_link_prepare (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
2064 if (result != GST_PAD_LINK_OK)
2067 GST_OBJECT_UNLOCK (srcpad);
2068 GST_OBJECT_UNLOCK (sinkpad);
2071 return result == GST_PAD_LINK_OK;
2075 * gst_pad_link_full:
2076 * @srcpad: the source #GstPad to link.
2077 * @sinkpad: the sink #GstPad to link.
2078 * @flags: the checks to validate when linking
2080 * Links the source pad and the sink pad.
2082 * This variant of #gst_pad_link provides a more granular control on the
2083 * checks being done when linking. While providing some considerable speedups
2084 * the caller of this method must be aware that wrong usage of those flags
2085 * can cause severe issues. Refer to the documentation of #GstPadLinkCheck
2086 * for more information.
2090 * Returns: A result code indicating if the connection worked or
2096 gst_pad_link_full (GstPad * srcpad, GstPad * sinkpad, GstPadLinkCheck flags)
2098 GstPadLinkReturn result;
2101 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
2102 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), GST_PAD_LINK_WRONG_DIRECTION);
2103 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
2104 g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad),
2105 GST_PAD_LINK_WRONG_DIRECTION);
2107 /* Notify the parent early. See gst_pad_unlink for details. */
2108 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
2109 if (GST_IS_ELEMENT (parent)) {
2110 gst_element_post_message (parent,
2111 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
2112 GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, TRUE));
2114 gst_object_unref (parent);
2119 /* prepare will also lock the two pads */
2120 result = gst_pad_link_prepare (srcpad, sinkpad, flags);
2122 if (result != GST_PAD_LINK_OK)
2125 /* must set peers before calling the link function */
2126 GST_PAD_PEER (srcpad) = sinkpad;
2127 GST_PAD_PEER (sinkpad) = srcpad;
2129 GST_OBJECT_UNLOCK (sinkpad);
2130 GST_OBJECT_UNLOCK (srcpad);
2132 /* FIXME released the locks here, concurrent thread might link
2133 * something else. */
2134 if (GST_PAD_LINKFUNC (srcpad)) {
2135 /* this one will call the peer link function */
2136 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
2137 } else if (GST_PAD_LINKFUNC (sinkpad)) {
2138 /* if no source link function, we need to call the sink link
2139 * function ourselves. */
2140 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
2142 result = GST_PAD_LINK_OK;
2145 GST_OBJECT_LOCK (srcpad);
2146 GST_OBJECT_LOCK (sinkpad);
2148 if (result == GST_PAD_LINK_OK) {
2149 GST_OBJECT_UNLOCK (sinkpad);
2150 GST_OBJECT_UNLOCK (srcpad);
2152 /* fire off a signal to each of the pads telling them
2153 * that they've been linked */
2154 g_signal_emit (srcpad, gst_pad_signals[PAD_LINKED], 0, sinkpad);
2155 g_signal_emit (sinkpad, gst_pad_signals[PAD_LINKED], 0, srcpad);
2157 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
2158 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2160 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
2161 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2163 GST_PAD_PEER (srcpad) = NULL;
2164 GST_PAD_PEER (sinkpad) = NULL;
2166 GST_OBJECT_UNLOCK (sinkpad);
2167 GST_OBJECT_UNLOCK (srcpad);
2172 gst_element_post_message (parent,
2173 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
2174 GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, FALSE));
2175 gst_object_unref (parent);
2183 * @srcpad: the source #GstPad to link.
2184 * @sinkpad: the sink #GstPad to link.
2186 * Links the source pad and the sink pad.
2188 * Returns: A result code indicating if the connection worked or
2194 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
2196 return gst_pad_link_full (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
2200 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
2202 GstPadTemplate **template_p;
2204 /* this function would need checks if it weren't static */
2206 GST_OBJECT_LOCK (pad);
2207 template_p = &pad->padtemplate;
2208 gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
2209 GST_OBJECT_UNLOCK (pad);
2212 gst_pad_template_pad_created (templ, pad);
2216 * gst_pad_get_pad_template:
2219 * Gets the template for @pad.
2221 * Returns: (transfer none): the #GstPadTemplate from which this pad was
2222 * instantiated, or %NULL if this pad has no template.
2224 * FIXME: currently returns an unrefcounted padtemplate.
2227 gst_pad_get_pad_template (GstPad * pad)
2229 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2231 return GST_PAD_PAD_TEMPLATE (pad);
2235 /* should be called with the pad LOCK held */
2236 /* refs the caps, so caller is responsible for getting it unreffed */
2238 gst_pad_get_caps_unlocked (GstPad * pad)
2240 GstCaps *result = NULL;
2241 GstPadTemplate *templ;
2243 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
2245 if (GST_PAD_GETCAPSFUNC (pad)) {
2246 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2247 "dispatching to pad getcaps function");
2249 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
2250 GST_OBJECT_UNLOCK (pad);
2251 result = GST_PAD_GETCAPSFUNC (pad) (pad);
2252 GST_OBJECT_LOCK (pad);
2253 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
2255 if (result == NULL) {
2256 g_critical ("pad %s:%s returned NULL caps from getcaps function",
2257 GST_DEBUG_PAD_NAME (pad));
2259 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2260 "pad getcaps returned %" GST_PTR_FORMAT, result);
2261 #ifndef G_DISABLE_ASSERT
2262 /* check that the returned caps are a real subset of the template caps */
2263 if (GST_PAD_PAD_TEMPLATE (pad)) {
2264 const GstCaps *templ_caps =
2265 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2266 if (!gst_caps_is_subset (result, templ_caps)) {
2269 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
2270 "pad returned caps %" GST_PTR_FORMAT
2271 " which are not a real subset of its template caps %"
2272 GST_PTR_FORMAT, result, templ_caps);
2274 ("pad %s:%s returned caps which are not a real "
2275 "subset of its template caps", GST_DEBUG_PAD_NAME (pad));
2276 temp = gst_caps_intersect (templ_caps, result);
2277 gst_caps_unref (result);
2285 if ((templ = GST_PAD_PAD_TEMPLATE (pad))) {
2286 result = GST_PAD_TEMPLATE_CAPS (templ);
2287 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2288 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
2291 result = gst_caps_ref (result);
2294 if ((result = GST_PAD_CAPS (pad))) {
2295 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2296 "using pad caps %p %" GST_PTR_FORMAT, result, result);
2298 result = gst_caps_ref (result);
2302 /* this almost never happens */
2303 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
2304 result = gst_caps_new_empty ();
2310 /* FIXME-0.11: what about making this the default and using
2311 * gst_caps_make_writable() explicitly where needed
2314 * gst_pad_get_caps_reffed:
2315 * @pad: a #GstPad to get the capabilities of.
2317 * Gets the capabilities this pad can produce or consume. Preferred function if
2318 * one only wants to read or intersect the caps.
2320 * Returns: (transfer full): the caps of the pad with incremented ref-count.
2325 gst_pad_get_caps_reffed (GstPad * pad)
2327 GstCaps *result = NULL;
2329 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2331 GST_OBJECT_LOCK (pad);
2333 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
2335 result = gst_pad_get_caps_unlocked (pad);
2337 GST_OBJECT_UNLOCK (pad);
2344 * @pad: a #GstPad to get the capabilities of.
2346 * Gets the capabilities this pad can produce or consume.
2347 * Note that this method doesn't necessarily return the caps set by
2348 * gst_pad_set_caps() - use GST_PAD_CAPS() for that instead.
2349 * gst_pad_get_caps returns all possible caps a pad can operate with, using
2350 * the pad's get_caps function;
2351 * this returns the pad template caps if not explicitly set.
2353 * Returns: (transfer full): a newly allocated copy of the #GstCaps of this pad
2358 gst_pad_get_caps (GstPad * pad)
2360 GstCaps *result = gst_pad_get_caps_reffed (pad);
2362 /* be sure that we have a copy */
2363 if (G_LIKELY (result))
2364 result = gst_caps_make_writable (result);
2369 /* FIXME-0.11: what about making this the default and using
2370 * gst_caps_make_writable() explicitly where needed
2373 * gst_pad_peer_get_caps_reffed:
2374 * @pad: a #GstPad to get the capabilities of.
2376 * Gets the capabilities of the peer connected to this pad. Preferred function
2377 * if one only wants to read or intersect the caps.
2379 * Returns: (transfer full): the caps of the pad with incremented ref-count
2384 gst_pad_peer_get_caps_reffed (GstPad * pad)
2387 GstCaps *result = NULL;
2389 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2391 GST_OBJECT_LOCK (pad);
2393 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2395 peerpad = GST_PAD_PEER (pad);
2396 if (G_UNLIKELY (peerpad == NULL))
2399 gst_object_ref (peerpad);
2400 GST_OBJECT_UNLOCK (pad);
2402 result = gst_pad_get_caps_reffed (peerpad);
2404 gst_object_unref (peerpad);
2410 GST_OBJECT_UNLOCK (pad);
2416 * gst_pad_peer_get_caps:
2417 * @pad: a #GstPad to get the peer capabilities of.
2419 * Gets the capabilities of the peer connected to this pad. Similar to
2420 * gst_pad_get_caps().
2422 * Returns: (transfer full): a newly allocated copy of the #GstCaps of the
2423 * peer pad. Use gst_caps_unref() to get rid of it. This function
2424 * returns %NULL if there is no peer pad.
2427 gst_pad_peer_get_caps (GstPad * pad)
2430 GstCaps *result = NULL;
2432 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2434 GST_OBJECT_LOCK (pad);
2436 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2438 peerpad = GST_PAD_PEER (pad);
2439 if (G_UNLIKELY (peerpad == NULL))
2442 gst_object_ref (peerpad);
2443 GST_OBJECT_UNLOCK (pad);
2445 result = gst_pad_get_caps (peerpad);
2447 gst_object_unref (peerpad);
2453 GST_OBJECT_UNLOCK (pad);
2459 fixate_value (GValue * dest, const GValue * src)
2461 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
2462 g_value_init (dest, G_TYPE_INT);
2463 g_value_set_int (dest, gst_value_get_int_range_min (src));
2464 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
2465 g_value_init (dest, G_TYPE_DOUBLE);
2466 g_value_set_double (dest, gst_value_get_double_range_min (src));
2467 } else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
2468 gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
2469 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
2470 GValue temp = { 0 };
2472 /* list could be empty */
2473 if (gst_value_list_get_size (src) <= 0)
2476 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
2478 if (!fixate_value (dest, &temp))
2479 gst_value_init_and_copy (dest, &temp);
2480 g_value_unset (&temp);
2481 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
2482 gboolean res = FALSE;
2485 len = gst_value_array_get_size (src);
2486 g_value_init (dest, GST_TYPE_ARRAY);
2487 for (n = 0; n < len; n++) {
2489 const GValue *orig_kid = gst_value_array_get_value (src, n);
2491 if (!fixate_value (&kid, orig_kid))
2492 gst_value_init_and_copy (&kid, orig_kid);
2495 gst_value_array_append_value (dest, &kid);
2496 g_value_unset (&kid);
2500 g_value_unset (dest);
2511 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
2513 GstStructure *s = data;
2516 if (fixate_value (&v, value)) {
2517 gst_structure_id_set_value (s, field_id, &v);
2525 * gst_pad_fixate_caps:
2526 * @pad: a #GstPad to fixate
2527 * @caps: the #GstCaps to fixate
2529 * Fixate a caps on the given pad. Modifies the caps in place, so you should
2530 * make sure that the caps are actually writable (see gst_caps_make_writable()).
2533 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
2535 GstPadFixateCapsFunction fixatefunc;
2538 g_return_if_fail (GST_IS_PAD (pad));
2539 g_return_if_fail (caps != NULL);
2540 g_return_if_fail (!gst_caps_is_empty (caps));
2541 /* FIXME-0.11: do not allow fixating any-caps
2542 * g_return_if_fail (!gst_caps_is_any (caps));
2545 if (gst_caps_is_fixed (caps) || gst_caps_is_any (caps))
2548 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
2550 fixatefunc (pad, caps);
2553 /* default fixation */
2554 gst_caps_truncate (caps);
2555 s = gst_caps_get_structure (caps, 0);
2556 gst_structure_foreach (s, gst_pad_default_fixate, s);
2559 /* Default accept caps implementation just checks against
2560 * against the allowed caps for the pad */
2562 gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
2564 /* get the caps and see if it intersects to something not empty */
2566 gboolean result = FALSE;
2568 GST_DEBUG_OBJECT (pad, "caps %" GST_PTR_FORMAT, caps);
2570 allowed = gst_pad_get_caps_reffed (pad);
2572 goto nothing_allowed;
2574 GST_DEBUG_OBJECT (pad, "allowed caps %" GST_PTR_FORMAT, allowed);
2576 result = gst_caps_can_intersect (allowed, caps);
2578 gst_caps_unref (allowed);
2585 GST_DEBUG_OBJECT (pad, "no caps allowed on the pad");
2591 * gst_pad_accept_caps:
2592 * @pad: a #GstPad to check
2593 * @caps: a #GstCaps to check on the pad
2595 * Check if the given pad accepts the caps.
2597 * Returns: TRUE if the pad can accept the caps.
2600 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2603 GstPadAcceptCapsFunction acceptfunc;
2604 GstCaps *existing = NULL;
2606 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2608 /* any pad can be unnegotiated */
2612 /* lock for checking the existing caps */
2613 GST_OBJECT_LOCK (pad);
2614 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
2615 /* The current caps on a pad are trivially acceptable */
2616 if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
2617 if (caps == existing || gst_caps_is_equal (caps, existing))
2620 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2621 GST_OBJECT_UNLOCK (pad);
2623 if (G_LIKELY (acceptfunc)) {
2624 /* we can call the function */
2625 result = acceptfunc (pad, caps);
2626 GST_DEBUG_OBJECT (pad, "acceptfunc returned %d", result);
2628 /* Only null if the element explicitly unset it */
2629 result = gst_pad_acceptcaps_default (pad, caps);
2630 GST_DEBUG_OBJECT (pad, "default acceptcaps returned %d", result);
2637 GST_DEBUG_OBJECT (pad, "pad had same caps");
2638 GST_OBJECT_UNLOCK (pad);
2644 * gst_pad_peer_accept_caps:
2645 * @pad: a #GstPad to check the peer of
2646 * @caps: a #GstCaps to check on the pad
2648 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2651 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2654 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2659 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2661 GST_OBJECT_LOCK (pad);
2663 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
2665 peerpad = GST_PAD_PEER (pad);
2666 if (G_UNLIKELY (peerpad == NULL))
2669 gst_object_ref (peerpad);
2670 /* release lock before calling external methods but keep ref to pad */
2671 GST_OBJECT_UNLOCK (pad);
2673 result = gst_pad_accept_caps (peerpad, caps);
2675 gst_object_unref (peerpad);
2681 GST_OBJECT_UNLOCK (pad);
2688 * @pad: a #GstPad to set the capabilities of.
2689 * @caps: (transfer none): a #GstCaps to set.
2691 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2692 * caps on the pad will be unreffed. This function refs the caps so you should
2693 * unref if as soon as you don't need it anymore.
2694 * It is possible to set NULL caps, which will make the pad unnegotiated
2697 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2698 * or bad parameters were provided to this function.
2703 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2705 GstPadSetCapsFunction setcaps;
2708 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2709 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2711 GST_OBJECT_LOCK (pad);
2712 existing = GST_PAD_CAPS (pad);
2713 if (existing == caps)
2716 if (gst_caps_is_equal (caps, existing))
2717 goto setting_same_caps;
2719 setcaps = GST_PAD_SETCAPSFUNC (pad);
2721 /* call setcaps function to configure the pad only if the
2722 * caps is not NULL */
2723 if (setcaps != NULL && caps) {
2724 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2725 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2726 GST_OBJECT_UNLOCK (pad);
2727 if (!setcaps (pad, caps))
2729 GST_OBJECT_LOCK (pad);
2730 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2732 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
2736 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2737 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %p %" GST_PTR_FORMAT, caps,
2739 GST_OBJECT_UNLOCK (pad);
2741 #if GLIB_CHECK_VERSION(2,26,0)
2742 g_object_notify_by_pspec ((GObject *) pad, pspec_caps);
2744 g_object_notify ((GObject *) pad, "caps");
2751 GST_OBJECT_UNLOCK (pad);
2756 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2757 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2758 "caps %p %" GST_PTR_FORMAT " same as existing, updating ptr only", caps,
2760 GST_OBJECT_UNLOCK (pad);
2767 GST_OBJECT_LOCK (pad);
2768 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2769 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2770 "caps %" GST_PTR_FORMAT " could not be set", caps);
2771 GST_OBJECT_UNLOCK (pad);
2778 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2782 /* See if pad accepts the caps */
2783 if (!gst_caps_can_intersect (caps, gst_pad_get_pad_template_caps (pad)))
2786 /* set caps on pad if call succeeds */
2787 res = gst_pad_set_caps (pad, caps);
2788 /* no need to unref the caps here, set_caps takes a ref and
2789 * our ref goes away when we leave this function. */
2795 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2796 "caps %" GST_PTR_FORMAT " not accepted", caps);
2801 /* returns TRUE if the src pad could be configured to accept the given caps */
2803 gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
2808 /* See if pad accepts the caps */
2809 if (!gst_pad_accept_caps (pad, caps))
2812 res = gst_pad_set_caps (pad, caps);
2820 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2821 "caps %" GST_PTR_FORMAT " not accepted", caps);
2827 * gst_pad_get_pad_template_caps:
2828 * @pad: a #GstPad to get the template capabilities from.
2830 * Gets the capabilities for @pad's template.
2832 * Returns: (transfer none): the #GstCaps of this pad template. If you intend
2833 * to keep a reference on the caps, make a copy (see gst_caps_copy ()).
2836 gst_pad_get_pad_template_caps (GstPad * pad)
2838 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2840 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2842 if (GST_PAD_PAD_TEMPLATE (pad))
2843 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2845 return gst_static_caps_get (&anycaps);
2850 * @pad: a #GstPad to get the peer of.
2852 * Gets the peer of @pad. This function refs the peer pad so
2853 * you need to unref it after use.
2855 * Returns: (transfer full): the peer #GstPad. Unref after usage.
2860 gst_pad_get_peer (GstPad * pad)
2864 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2866 GST_OBJECT_LOCK (pad);
2867 result = GST_PAD_PEER (pad);
2869 gst_object_ref (result);
2870 GST_OBJECT_UNLOCK (pad);
2876 * gst_pad_get_allowed_caps:
2879 * Gets the capabilities of the allowed media types that can flow through
2880 * @pad and its peer.
2882 * The allowed capabilities is calculated as the intersection of the results of
2883 * calling gst_pad_get_caps() on @pad and its peer. The caller owns a reference
2884 * on the resulting caps.
2886 * Returns: (transfer full): the allowed #GstCaps of the pad link. Unref the
2887 * caps when you no longer need it. This function returns NULL when @pad
2893 gst_pad_get_allowed_caps (GstPad * pad)
2900 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2902 GST_OBJECT_LOCK (pad);
2904 peer = GST_PAD_PEER (pad);
2905 if (G_UNLIKELY (peer == NULL))
2908 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting allowed caps");
2910 gst_object_ref (peer);
2911 GST_OBJECT_UNLOCK (pad);
2912 mycaps = gst_pad_get_caps_reffed (pad);
2914 peercaps = gst_pad_get_caps_reffed (peer);
2915 gst_object_unref (peer);
2917 caps = gst_caps_intersect (mycaps, peercaps);
2918 gst_caps_unref (peercaps);
2919 gst_caps_unref (mycaps);
2921 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "allowed caps %" GST_PTR_FORMAT,
2928 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2929 GST_OBJECT_UNLOCK (pad);
2936 * gst_pad_get_negotiated_caps:
2939 * Gets the capabilities of the media type that currently flows through @pad
2942 * This function can be used on both src and sinkpads. Note that srcpads are
2943 * always negotiated before sinkpads so it is possible that the negotiated caps
2944 * on the srcpad do not match the negotiated caps of the peer.
2946 * Returns: (transfer full): the negotiated #GstCaps of the pad link. Unref
2947 * the caps when you no longer need it. This function returns NULL when
2948 * the @pad has no peer or is not negotiated yet.
2953 gst_pad_get_negotiated_caps (GstPad * pad)
2958 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2960 GST_OBJECT_LOCK (pad);
2962 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2965 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
2967 caps = GST_PAD_CAPS (pad);
2969 gst_caps_ref (caps);
2970 GST_OBJECT_UNLOCK (pad);
2972 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
2979 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2980 GST_OBJECT_UNLOCK (pad);
2986 /* calls the buffer_alloc function on the given pad */
2987 static GstFlowReturn
2988 gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
2989 GstCaps * caps, GstBuffer ** buf)
2992 GstPadBufferAllocFunction bufferallocfunc;
2994 GST_OBJECT_LOCK (pad);
2995 /* when the pad is flushing we cannot give a buffer */
2996 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2999 bufferallocfunc = pad->bufferallocfunc;
3001 if (offset == GST_BUFFER_OFFSET_NONE) {
3002 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3003 "calling bufferallocfunc &%s (@%p) for size %d offset NONE",
3004 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), bufferallocfunc, size);
3006 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3007 "calling bufferallocfunc &%s (@%p) of for size %d offset %"
3008 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
3009 bufferallocfunc, size, offset);
3011 GST_OBJECT_UNLOCK (pad);
3013 /* G_LIKELY for now since most elements don't implement a buffer alloc
3014 * function and there is no default alloc proxy function as this is usually
3016 if (G_LIKELY (bufferallocfunc == NULL))
3019 ret = bufferallocfunc (pad, offset, size, caps, buf);
3021 if (G_UNLIKELY (ret != GST_FLOW_OK))
3024 /* no error, but NULL buffer means fallback to the default */
3025 if (G_UNLIKELY (*buf == NULL))
3028 /* If the buffer alloc function didn't set up the caps like it should,
3030 if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
3031 GST_WARNING_OBJECT (pad,
3032 "Buffer allocation function did not set caps. Setting");
3033 gst_buffer_set_caps (*buf, caps);
3039 /* pad was flushing */
3040 GST_OBJECT_UNLOCK (pad);
3041 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
3042 return GST_FLOW_WRONG_STATE;
3046 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3047 "alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
3052 /* fallback case, allocate a buffer of our own, add pad caps. */
3053 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
3055 if ((*buf = gst_buffer_try_new_and_alloc (size))) {
3056 GST_BUFFER_OFFSET (*buf) = offset;
3057 gst_buffer_set_caps (*buf, caps);
3060 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3061 "out of memory allocating %d bytes", size);
3062 return GST_FLOW_ERROR;
3067 /* FIXME 0.11: size should be unsigned */
3068 static GstFlowReturn
3069 gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
3070 GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
3075 gboolean caps_changed;
3077 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3078 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
3079 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
3080 g_return_val_if_fail (size >= 0, GST_FLOW_ERROR);
3082 GST_DEBUG_OBJECT (pad, "offset %" G_GUINT64_FORMAT ", size %d, caps %"
3083 GST_PTR_FORMAT, offset, size, caps);
3085 GST_OBJECT_LOCK (pad);
3086 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3087 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
3090 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3093 gst_object_ref (peer);
3094 GST_OBJECT_UNLOCK (pad);
3096 ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
3097 gst_object_unref (peer);
3099 if (G_UNLIKELY (ret != GST_FLOW_OK))
3102 /* FIXME, move capnego this into a base class? */
3103 newcaps = GST_BUFFER_CAPS (*buf);
3105 /* Lock for checking caps, pretty pointless as the _pad_push() function might
3106 * change it concurrently, one of the problems with automatic caps setting in
3107 * pad_alloc_and_set_caps. Worst case, if does a check too much, but only
3108 * when there is heavy renegotiation going on in both directions. */
3109 GST_OBJECT_LOCK (pad);
3110 caps_changed = newcaps && newcaps != GST_PAD_CAPS (pad);
3111 GST_OBJECT_UNLOCK (pad);
3113 /* we got a new datatype on the pad, see if it can handle it */
3114 if (G_UNLIKELY (caps_changed)) {
3115 GST_DEBUG_OBJECT (pad,
3116 "caps changed from %" GST_PTR_FORMAT " to %p %" GST_PTR_FORMAT,
3117 GST_PAD_CAPS (pad), newcaps, newcaps);
3118 if (G_UNLIKELY (!gst_pad_configure_src (pad, newcaps, setcaps)))
3119 goto not_negotiated;
3122 /* sanity check (only if caps are the same) */
3123 if (G_LIKELY (newcaps == caps) && G_UNLIKELY (GST_BUFFER_SIZE (*buf) < size))
3124 goto wrong_size_fallback;
3130 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
3131 GST_OBJECT_UNLOCK (pad);
3136 /* pad has no peer */
3137 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3138 "called bufferallocfunc but had no peer");
3139 GST_OBJECT_UNLOCK (pad);
3140 return GST_FLOW_NOT_LINKED;
3144 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3145 "alloc function returned error %s", gst_flow_get_name (ret));
3150 gst_buffer_unref (*buf);
3152 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3153 "alloc function returned unacceptable buffer");
3154 return GST_FLOW_NOT_NEGOTIATED;
3156 wrong_size_fallback:
3158 GST_CAT_ERROR_OBJECT (GST_CAT_PADS, pad, "buffer returned by alloc "
3159 "function is too small (%u < %d), doing fallback buffer alloc",
3160 GST_BUFFER_SIZE (*buf), size);
3162 gst_buffer_unref (*buf);
3164 if ((*buf = gst_buffer_try_new_and_alloc (size))) {
3165 GST_BUFFER_OFFSET (*buf) = offset;
3166 gst_buffer_set_caps (*buf, caps);
3169 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3170 "out of memory allocating %d bytes", size);
3171 return GST_FLOW_ERROR;
3177 * gst_pad_alloc_buffer:
3178 * @pad: a source #GstPad
3179 * @offset: the offset of the new buffer in the stream
3180 * @size: the size of the new buffer
3181 * @caps: the caps of the new buffer
3182 * @buf: a newly allocated buffer
3184 * Allocates a new, empty buffer optimized to push to pad @pad. This
3185 * function only works if @pad is a source pad and has a peer.
3187 * A new, empty #GstBuffer will be put in the @buf argument.
3188 * You need to check the caps of the buffer after performing this
3189 * function and renegotiate to the format if needed. If the caps changed, it is
3190 * possible that the buffer returned in @buf is not of the right size for the
3191 * new format, @buf needs to be unreffed and reallocated if this is the case.
3193 * Returns: a result code indicating success of the operation. Any
3194 * result code other than #GST_FLOW_OK is an error and @buf should
3196 * An error can occur if the pad is not connected or when the downstream
3197 * peer elements cannot provide an acceptable buffer.
3202 /* FIXME 0.11: size should be unsigned */
3204 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
3207 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
3211 * gst_pad_alloc_buffer_and_set_caps:
3212 * @pad: a source #GstPad
3213 * @offset: the offset of the new buffer in the stream
3214 * @size: the size of the new buffer
3215 * @caps: (transfer none): the caps of the new buffer
3216 * @buf: (out callee-allocates): a newly allocated buffer
3218 * In addition to the function gst_pad_alloc_buffer(), this function
3219 * automatically calls gst_pad_set_caps() when the caps of the
3220 * newly allocated buffer are different from the @pad caps.
3222 * After a renegotiation, the size of the new buffer returned in @buf could
3223 * be of the wrong size for the new format and must be unreffed an reallocated
3226 * Returns: a result code indicating success of the operation. Any
3227 * result code other than #GST_FLOW_OK is an error and @buf should
3229 * An error can occur if the pad is not connected or when the downstream
3230 * peer elements cannot provide an acceptable buffer.
3235 /* FIXME 0.11: size should be unsigned */
3237 gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
3238 GstCaps * caps, GstBuffer ** buf)
3240 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
3244 #ifndef GST_REMOVE_DEPRECATED
3252 int_link_iter_data_free (IntLinkIterData * data)
3254 g_list_free (data->list);
3255 g_slice_free (IntLinkIterData, data);
3259 static GstIteratorItem
3260 iterate_pad (GstIterator * it, GstPad * pad)
3262 gst_object_ref (pad);
3263 return GST_ITERATOR_ITEM_PASS;
3267 * gst_pad_iterate_internal_links_default:
3268 * @pad: the #GstPad to get the internal links of.
3270 * Iterate the list of pads to which the given pad is linked to inside of
3271 * the parent element.
3272 * This is the default handler, and thus returns an iterator of all of the
3273 * pads inside the parent element with opposite direction.
3275 * The caller must free this iterator after use with gst_iterator_free().
3277 * Returns: a #GstIterator of #GstPad, or NULL if @pad has no parent. Unref each
3278 * returned pad with gst_object_unref().
3283 gst_pad_iterate_internal_links_default (GstPad * pad)
3290 GstIteratorDisposeFunction dispose;
3292 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3294 #ifndef GST_REMOVE_DEPRECATED
3295 /* when we get here, the default handler for the iterate links is called,
3296 * which means that the user has not installed a custom one. We first check if
3297 * there is maybe a custom legacy function we can call. */
3298 if (GST_PAD_INTLINKFUNC (pad) &&
3299 GST_PAD_INTLINKFUNC (pad) != gst_pad_get_internal_links_default) {
3300 IntLinkIterData *data;
3302 /* make an iterator for the list. We can't protect the list with a
3303 * cookie. If we would take the cookie of the parent element, we need to
3304 * have a parent, which is not required for GST_PAD_INTLINKFUNC(). We could
3305 * cache the per-pad list and invalidate the list when a new call to
3306 * INTLINKFUNC() returned a different list but then this would only work if
3307 * two concurrent iterators were used and the last iterator would still be
3308 * thread-unsafe. Just don't use this method anymore. */
3309 data = g_slice_new (IntLinkIterData);
3310 data->list = ((GstPadIntLinkFunction) GST_PAD_INTLINKFUNC (pad)) (pad);
3313 GST_WARNING_OBJECT (pad, "Making unsafe iterator");
3315 cookie = &data->cookie;
3316 padlist = &data->list;
3318 dispose = (GstIteratorDisposeFunction) int_link_iter_data_free;
3319 /* reuse the pad lock, it's all we have here */
3320 lock = GST_OBJECT_GET_LOCK (pad);
3326 GST_OBJECT_LOCK (pad);
3327 parent = GST_PAD_PARENT (pad);
3328 if (!parent || !GST_IS_ELEMENT (parent))
3331 gst_object_ref (parent);
3332 GST_OBJECT_UNLOCK (pad);
3334 if (pad->direction == GST_PAD_SRC)
3335 padlist = &parent->sinkpads;
3337 padlist = &parent->srcpads;
3339 GST_DEBUG_OBJECT (pad, "Making iterator");
3341 cookie = &parent->pads_cookie;
3343 dispose = (GstIteratorDisposeFunction) gst_object_unref;
3344 lock = GST_OBJECT_GET_LOCK (parent);
3347 res = gst_iterator_new_list (GST_TYPE_PAD,
3348 lock, cookie, padlist, owner, (GstIteratorItemFunction) iterate_pad,
3356 GST_OBJECT_UNLOCK (pad);
3357 GST_DEBUG_OBJECT (pad, "no parent element");
3363 * gst_pad_iterate_internal_links:
3364 * @pad: the GstPad to get the internal links of.
3366 * Gets an iterator for the pads to which the given pad is linked to inside
3367 * of the parent element.
3369 * Each #GstPad element yielded by the iterator will have its refcount increased,
3370 * so unref after use.
3372 * Free-function: gst_iterator_free
3374 * Returns: (transfer full): a new #GstIterator of #GstPad or %NULL when the
3375 * pad does not have an iterator function configured. Use
3376 * gst_iterator_free() after usage.
3381 gst_pad_iterate_internal_links (GstPad * pad)
3383 GstIterator *res = NULL;
3385 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3387 if (GST_PAD_ITERINTLINKFUNC (pad))
3388 res = GST_PAD_ITERINTLINKFUNC (pad) (pad);
3393 #ifndef GST_REMOVE_DEPRECATED
3395 add_unref_pad_to_list (GstPad * pad, GList ** list)
3397 *list = g_list_prepend (*list, pad);
3398 gst_object_unref (pad);
3403 * gst_pad_get_internal_links_default:
3404 * @pad: the #GstPad to get the internal links of.
3406 * Gets a list of pads to which the given pad is linked to
3407 * inside of the parent element.
3408 * This is the default handler, and thus returns a list of all of the
3409 * pads inside the parent element with opposite direction.
3411 * The caller must free this list after use with g_list_free().
3413 * Returns: (transfer full) (element-type Gst.Pad): a newly allocated #GList
3414 * of pads, or NULL if the pad has no parent.
3418 * Deprecated: This function does not ref the pads in the list so that they
3419 * could become invalid by the time the application accesses them. It's also
3420 * possible that the list changes while handling the pads, which the caller of
3421 * this function is unable to know. Use the thread-safe
3422 * gst_pad_iterate_internal_links_default() instead.
3424 #ifndef GST_REMOVE_DEPRECATED
3426 gst_pad_get_internal_links_default (GstPad * pad)
3431 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3433 GST_WARNING_OBJECT (pad, "Unsafe internal links used");
3435 /* when we get here, the default handler for get_internal_links is called,
3436 * which means that the user has not installed a custom one. We first check if
3437 * there is maybe a custom iterate function we can call. */
3438 if (GST_PAD_ITERINTLINKFUNC (pad) &&
3439 GST_PAD_ITERINTLINKFUNC (pad) != gst_pad_iterate_internal_links_default) {
3441 GstIteratorResult ires;
3442 gboolean done = FALSE;
3444 it = gst_pad_iterate_internal_links (pad);
3445 /* loop over the iterator and put all elements into a list, we also
3446 * immediately unref them, which is bad. */
3448 ires = gst_iterator_foreach (it, (GFunc) add_unref_pad_to_list, &res);
3450 case GST_ITERATOR_OK:
3451 case GST_ITERATOR_DONE:
3452 case GST_ITERATOR_ERROR:
3455 case GST_ITERATOR_RESYNC:
3456 /* restart, discard previous list */
3457 gst_iterator_resync (it);
3464 gst_iterator_free (it);
3466 /* lock pad, check and ref parent */
3467 GST_OBJECT_LOCK (pad);
3468 parent = GST_PAD_PARENT (pad);
3469 if (!parent || !GST_IS_ELEMENT (parent))
3472 parent = gst_object_ref (parent);
3473 GST_OBJECT_UNLOCK (pad);
3475 /* now lock the parent while we copy the pads */
3476 GST_OBJECT_LOCK (parent);
3477 if (pad->direction == GST_PAD_SRC)
3478 res = g_list_copy (parent->sinkpads);
3480 res = g_list_copy (parent->srcpads);
3481 GST_OBJECT_UNLOCK (parent);
3483 gst_object_unref (parent);
3486 /* At this point pads can be changed and unreffed. Nothing we can do about it
3487 * because for compatibility reasons this function cannot ref the pads or
3488 * notify the app that the list changed. */
3494 GST_DEBUG_OBJECT (pad, "no parent");
3495 GST_OBJECT_UNLOCK (pad);
3499 #endif /* GST_REMOVE_DEPRECATED */
3502 * gst_pad_get_internal_links:
3503 * @pad: the #GstPad to get the internal links of.
3505 * Gets a list of pads to which the given pad is linked to
3506 * inside of the parent element.
3507 * The caller must free this list after use.
3511 * Returns: (transfer full) (element-type Gst.Pad): a newly allocated #GList
3512 * of pads, free with g_list_free().
3514 * Deprecated: This function does not ref the pads in the list so that they
3515 * could become invalid by the time the application accesses them. It's also
3516 * possible that the list changes while handling the pads, which the caller of
3517 * this function is unable to know. Use the thread-safe
3518 * gst_pad_iterate_internal_links() instead.
3520 #ifndef GST_REMOVE_DEPRECATED
3521 #ifdef GST_DISABLE_DEPRECATED
3522 GList *gst_pad_get_internal_links (GstPad * pad);
3525 gst_pad_get_internal_links (GstPad * pad)
3529 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3531 GST_WARNING_OBJECT (pad, "Calling unsafe internal links");
3533 if (GST_PAD_INTLINKFUNC (pad))
3534 res = ((GstPadIntLinkFunction) GST_PAD_INTLINKFUNC (pad)) (pad);
3538 #endif /* GST_REMOVE_DEPRECATED */
3541 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
3543 gboolean result = FALSE;
3545 gboolean done = FALSE;
3548 GList *pushed_pads = NULL;
3550 GST_INFO_OBJECT (pad, "Sending event %p (%s) to all internally linked pads",
3551 event, GST_EVENT_TYPE_NAME (event));
3553 iter = gst_pad_iterate_internal_links (pad);
3559 switch (gst_iterator_next (iter, &item)) {
3560 case GST_ITERATOR_OK:
3561 eventpad = GST_PAD_CAST (item);
3563 /* if already pushed, skip */
3564 if (g_list_find (pushed_pads, eventpad)) {
3565 gst_object_unref (item);
3569 if (GST_PAD_IS_SRC (eventpad)) {
3570 /* for each pad we send to, we should ref the event; it's up
3571 * to downstream to unref again when handled. */
3572 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
3573 event, GST_EVENT_TYPE_NAME (event),
3574 GST_DEBUG_PAD_NAME (eventpad));
3575 gst_event_ref (event);
3576 result |= gst_pad_push_event (eventpad, event);
3578 /* we only send the event on one pad, multi-sinkpad elements
3579 * should implement a handler */
3580 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
3581 event, GST_EVENT_TYPE_NAME (event),
3582 GST_DEBUG_PAD_NAME (eventpad));
3583 result = gst_pad_push_event (eventpad, event);
3588 pushed_pads = g_list_prepend (pushed_pads, eventpad);
3590 gst_object_unref (item);
3592 case GST_ITERATOR_RESYNC:
3593 /* We don't reset the result here because we don't push the event
3594 * again on pads that got the event already and because we need
3595 * to consider the result of the previous pushes */
3596 gst_iterator_resync (iter);
3598 case GST_ITERATOR_ERROR:
3599 GST_ERROR_OBJECT (pad, "Could not iterate over internally linked pads");
3602 case GST_ITERATOR_DONE:
3607 gst_iterator_free (iter);
3611 /* If this is a sinkpad and we don't have pads to send the event to, we
3612 * return TRUE. This is so that when using the default handler on a sink
3613 * element, we don't fail to push it. */
3615 result = GST_PAD_IS_SINK (pad);
3617 g_list_free (pushed_pads);
3619 /* we handled the incoming event so we unref once */
3621 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
3622 gst_event_unref (event);
3629 * gst_pad_event_default:
3630 * @pad: a #GstPad to call the default event handler on.
3631 * @event: (transfer full): the #GstEvent to handle.
3633 * Invokes the default event handler for the given pad. End-of-stream and
3634 * discontinuity events are handled specially, and then the event is sent to all
3635 * pads internally linked to @pad. Note that if there are many possible sink
3636 * pads that are internally linked to @pad, only one will be sent an event.
3637 * Multi-sinkpad elements should implement custom event handlers.
3639 * Returns: TRUE if the event was sent successfully.
3642 gst_pad_event_default (GstPad * pad, GstEvent * event)
3644 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3645 g_return_val_if_fail (event != NULL, FALSE);
3647 GST_LOG_OBJECT (pad, "default event handler");
3649 switch (GST_EVENT_TYPE (event)) {
3652 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
3653 gst_pad_pause_task (pad);
3660 return gst_pad_event_default_dispatch (pad, event);
3664 * gst_pad_dispatcher:
3665 * @pad: a #GstPad to dispatch.
3666 * @dispatch: the #GstPadDispatcherFunction to call.
3667 * @data: (closure): gpointer user data passed to the dispatcher function.
3669 * Invokes the given dispatcher function on each respective peer of
3670 * all pads that are internally linked to the given pad.
3671 * The GstPadDispatcherFunction should return TRUE when no further pads
3672 * need to be processed.
3674 * Returns: TRUE if one of the dispatcher functions returned TRUE.
3677 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
3680 gboolean res = FALSE;
3681 GstIterator *iter = NULL;
3682 gboolean done = FALSE;
3685 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3686 g_return_val_if_fail (dispatch != NULL, FALSE);
3688 iter = gst_pad_iterate_internal_links (pad);
3694 switch (gst_iterator_next (iter, &item)) {
3695 case GST_ITERATOR_OK:
3697 GstPad *int_pad = GST_PAD_CAST (item);
3698 GstPad *int_peer = gst_pad_get_peer (int_pad);
3701 GST_DEBUG_OBJECT (int_pad, "dispatching to peer %s:%s",
3702 GST_DEBUG_PAD_NAME (int_peer));
3703 done = res = dispatch (int_peer, data);
3704 gst_object_unref (int_peer);
3706 GST_DEBUG_OBJECT (int_pad, "no peer");
3709 gst_object_unref (item);
3711 case GST_ITERATOR_RESYNC:
3712 gst_iterator_resync (iter);
3714 case GST_ITERATOR_ERROR:
3716 GST_ERROR_OBJECT (pad, "Could not iterate internally linked pads");
3718 case GST_ITERATOR_DONE:
3723 gst_iterator_free (iter);
3725 GST_DEBUG_OBJECT (pad, "done, result %d", res);
3734 * @pad: a #GstPad to invoke the default query on.
3735 * @query: (transfer none): the #GstQuery to perform.
3737 * Dispatches a query to a pad. The query should have been allocated by the
3738 * caller via one of the type-specific allocation functions. The element that
3739 * the pad belongs to is responsible for filling the query with an appropriate
3740 * response, which should then be parsed with a type-specific query parsing
3743 * Again, the caller is responsible for both the allocation and deallocation of
3744 * the query structure.
3746 * Please also note that some queries might need a running pipeline to work.
3748 * Returns: TRUE if the query could be performed.
3751 gst_pad_query (GstPad * pad, GstQuery * query)
3753 GstPadQueryFunction func;
3755 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3756 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
3758 GST_DEBUG_OBJECT (pad, "sending query %p", query);
3760 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
3763 return func (pad, query);
3767 GST_DEBUG_OBJECT (pad, "had no query function");
3773 * gst_pad_peer_query:
3774 * @pad: a #GstPad to invoke the peer query on.
3775 * @query: (transfer none): the #GstQuery to perform.
3777 * Performs gst_pad_query() on the peer of @pad.
3779 * The caller is responsible for both the allocation and deallocation of
3780 * the query structure.
3782 * Returns: TRUE if the query could be performed. This function returns %FALSE
3783 * if @pad has no peer.
3788 gst_pad_peer_query (GstPad * pad, GstQuery * query)
3793 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3794 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
3796 GST_OBJECT_LOCK (pad);
3798 GST_DEBUG_OBJECT (pad, "peer query");
3800 peerpad = GST_PAD_PEER (pad);
3801 if (G_UNLIKELY (peerpad == NULL))
3804 gst_object_ref (peerpad);
3805 GST_OBJECT_UNLOCK (pad);
3807 result = gst_pad_query (peerpad, query);
3809 gst_object_unref (peerpad);
3816 GST_WARNING_OBJECT (pad, "pad has no peer");
3817 GST_OBJECT_UNLOCK (pad);
3823 * gst_pad_query_default:
3824 * @pad: a #GstPad to call the default query handler on.
3825 * @query: (transfer none): the #GstQuery to handle.
3827 * Invokes the default query handler for the given pad.
3828 * The query is sent to all pads internally linked to @pad. Note that
3829 * if there are many possible sink pads that are internally linked to
3830 * @pad, only one will be sent the query.
3831 * Multi-sinkpad elements should implement custom query handlers.
3833 * Returns: TRUE if the query was performed successfully.
3836 gst_pad_query_default (GstPad * pad, GstQuery * query)
3838 switch (GST_QUERY_TYPE (query)) {
3839 case GST_QUERY_POSITION:
3840 case GST_QUERY_SEEKING:
3841 case GST_QUERY_FORMATS:
3842 case GST_QUERY_LATENCY:
3843 case GST_QUERY_JITTER:
3844 case GST_QUERY_RATE:
3845 case GST_QUERY_CONVERT:
3847 return gst_pad_dispatcher
3848 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
3852 #if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
3853 /* FIXME: why isn't this on a GstElement ? */
3855 * gst_pad_load_and_link:
3856 * @self: an #xmlNodePtr to read the description from.
3857 * @parent: the #GstObject element that owns the pad.
3859 * Reads the pad definition from the XML node and links the given pad
3860 * in the element to a pad of an element up in the hierarchy.
3863 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
3865 xmlNodePtr field = self->xmlChildrenNode;
3866 GstPad *pad = NULL, *targetpad;
3867 GstPadTemplate *tmpl;
3871 GstObject *grandparent;
3875 if (!strcmp ((char *) field->name, "name")) {
3876 name = (gchar *) xmlNodeGetContent (field);
3877 pad = gst_element_get_static_pad (GST_ELEMENT (parent), name);
3878 if ((!pad) || ((tmpl = gst_pad_get_pad_template (pad))
3879 && (GST_PAD_REQUEST == GST_PAD_TEMPLATE_PRESENCE (tmpl))))
3880 pad = gst_element_get_request_pad (GST_ELEMENT (parent), name);
3882 } else if (!strcmp ((char *) field->name, "peer")) {
3883 peer = (gchar *) xmlNodeGetContent (field);
3885 field = field->next;
3887 g_return_if_fail (pad != NULL);
3892 split = g_strsplit (peer, ".", 2);
3894 if (split[0] == NULL || split[1] == NULL) {
3895 GST_CAT_DEBUG_OBJECT (GST_CAT_XML, pad,
3896 "Could not parse peer '%s', leaving unlinked", peer);
3903 g_return_if_fail (split[0] != NULL);
3904 g_return_if_fail (split[1] != NULL);
3906 grandparent = gst_object_get_parent (parent);
3908 if (grandparent && GST_IS_BIN (grandparent)) {
3909 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
3916 targetpad = gst_element_get_static_pad (target, split[1]);
3918 targetpad = gst_element_get_request_pad (target, split[1]);
3920 if (targetpad == NULL)
3923 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
3924 gst_pad_link (pad, targetpad);
3926 gst_pad_link (targetpad, pad);
3933 * gst_pad_save_thyself:
3934 * @pad: a #GstPad to save.
3935 * @parent: the parent #xmlNodePtr to save the description in.
3937 * Saves the pad into an xml representation.
3939 * Returns: the #xmlNodePtr representation of the pad.
3942 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
3947 g_return_val_if_fail (GST_IS_PAD (object), NULL);
3949 pad = GST_PAD_CAST (object);
3951 xmlNewChild (parent, NULL, (xmlChar *) "name",
3952 (xmlChar *) GST_PAD_NAME (pad));
3954 if (GST_PAD_IS_SRC (pad)) {
3955 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "source");
3956 } else if (GST_PAD_IS_SINK (pad)) {
3957 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "sink");
3959 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "unknown");
3962 if (GST_PAD_PEER (pad) != NULL) {
3965 peer = GST_PAD_PEER (pad);
3966 /* first check to see if the peer's parent's parent is the same */
3967 /* we just save it off */
3968 content = g_strdup_printf ("%s.%s",
3969 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
3970 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
3973 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
3980 * gst_ghost_pad_save_thyself:
3981 * @pad: a ghost #GstPad to save.
3982 * @parent: the parent #xmlNodePtr to save the description in.
3984 * Saves the ghost pad into an xml representation.
3986 * Returns: the #xmlNodePtr representation of the pad.
3989 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
3993 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
3995 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
3996 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
3997 xmlNewChild (self, NULL, (xmlChar *) "parent",
3998 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
4000 /* FIXME FIXME FIXME! */
4005 #endif /* GST_DISABLE_LOADSAVE */
4008 * should be called with pad OBJECT_LOCK and STREAM_LOCK held.
4009 * GST_PAD_IS_BLOCKED (pad) == TRUE when this function is
4012 * This function performs the pad blocking when an event, buffer push
4013 * or buffer_alloc is performed on a _SRC_ pad. It blocks the
4014 * streaming thread after informing the pad has been blocked.
4016 * An application can with this method wait and block any streaming
4017 * thread and perform operations such as seeking or linking.
4019 * Two methods are available for notifying the application of the
4021 * - the callback method, which happens in the STREAMING thread with
4022 * the STREAM_LOCK held. With this method, the most useful way of
4023 * dealing with the callback is to post a message to the main thread
4024 * where the pad block can then be handled outside of the streaming
4025 * thread. With the last method one can perform all operations such
4026 * as doing a state change, linking, unblocking, seeking etc on the
4028 * - the GCond signal method, which makes any thread unblock when
4029 * the pad block happens.
4031 * During the actual blocking state, the GST_PAD_BLOCKING flag is set.
4032 * The GST_PAD_BLOCKING flag is unset when the pad was unblocked.
4036 static GstFlowReturn
4037 handle_pad_block (GstPad * pad)
4039 GstPadBlockCallback callback;
4041 GstFlowReturn ret = GST_FLOW_OK;
4043 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
4045 /* flushing, don't bother trying to block and return WRONG_STATE
4047 if (GST_PAD_IS_FLUSHING (pad))
4048 goto flushingnonref;
4050 /* we grab an extra ref for the callbacks, this is probably not
4051 * needed (callback code does not have a ref and cannot unref). I
4052 * think this was done to make it possible to unref the element in
4053 * the callback, which is in the end totally impossible as it
4054 * requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
4055 * all taken when calling this function. */
4056 gst_object_ref (pad);
4058 while (GST_PAD_IS_BLOCKED (pad)) {
4060 /* we either have a callback installed to notify the block or
4061 * some other thread is doing a GCond wait. */
4062 callback = pad->block_callback;
4063 pad->abidata.ABI.block_callback_called = TRUE;
4065 /* there is a callback installed, call it. We release the
4066 * lock so that the callback can do something useful with the
4068 user_data = pad->block_data;
4069 GST_OBJECT_UNLOCK (pad);
4070 callback (pad, TRUE, user_data);
4071 GST_OBJECT_LOCK (pad);
4073 /* we released the lock, recheck flushing */
4074 if (GST_PAD_IS_FLUSHING (pad))
4077 /* no callback, signal the thread that is doing a GCond wait
4079 GST_PAD_BLOCK_BROADCAST (pad);
4081 } while (pad->abidata.ABI.block_callback_called == FALSE
4082 && GST_PAD_IS_BLOCKED (pad));
4084 /* OBJECT_LOCK could have been released when we did the callback, which
4085 * then could have made the pad unblock so we need to check the blocking
4086 * condition again. */
4087 if (!GST_PAD_IS_BLOCKED (pad))
4090 /* now we block the streaming thread. It can be unlocked when we
4091 * deactivate the pad (which will also set the FLUSHING flag) or
4092 * when the pad is unblocked. A flushing event will also unblock
4093 * the pad after setting the FLUSHING flag. */
4094 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4095 "Waiting to be unblocked or set flushing");
4096 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKING);
4097 GST_PAD_BLOCK_WAIT (pad);
4098 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKING);
4100 /* see if we got unblocked by a flush or not */
4101 if (GST_PAD_IS_FLUSHING (pad))
4105 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
4107 /* when we get here, the pad is unblocked again and we perform
4108 * the needed unblock code. */
4109 callback = pad->block_callback;
4111 /* we need to call the callback */
4112 user_data = pad->block_data;
4113 GST_OBJECT_UNLOCK (pad);
4114 callback (pad, FALSE, user_data);
4115 GST_OBJECT_LOCK (pad);
4117 /* we need to signal the thread waiting on the GCond */
4118 GST_PAD_BLOCK_BROADCAST (pad);
4121 gst_object_unref (pad);
4127 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
4128 return GST_FLOW_WRONG_STATE;
4132 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
4133 gst_object_unref (pad);
4134 return GST_FLOW_WRONG_STATE;
4138 /**********************************************************************
4139 * Data passing functions
4143 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
4146 GValue args[2] = { {0}, {0} };
4151 g_value_init (&ret, G_TYPE_BOOLEAN);
4152 g_value_set_boolean (&ret, TRUE);
4153 g_value_init (&args[0], GST_TYPE_PAD);
4154 g_value_set_object (&args[0], pad);
4155 g_value_init (&args[1], GST_TYPE_MINI_OBJECT);
4156 gst_value_set_mini_object (&args[1], obj);
4158 if (GST_IS_EVENT (obj))
4159 detail = event_quark;
4161 detail = buffer_quark;
4164 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
4165 res = g_value_get_boolean (&ret);
4168 g_value_unset (&ret);
4169 g_value_unset (&args[0]);
4170 g_value_unset (&args[1]);
4176 gst_pad_data_unref (gboolean is_buffer, void *data)
4178 if (G_LIKELY (is_buffer)) {
4179 gst_buffer_unref (data);
4181 gst_buffer_list_unref (data);
4186 gst_pad_data_get_caps (gboolean is_buffer, void *data)
4190 if (G_LIKELY (is_buffer)) {
4191 caps = GST_BUFFER_CAPS (data);
4195 if ((buf = gst_buffer_list_get (GST_BUFFER_LIST_CAST (data), 0, 0)))
4196 caps = GST_BUFFER_CAPS (buf);
4203 /* this is the chain function that does not perform the additional argument
4204 * checking for that little extra speed.
4206 static inline GstFlowReturn
4207 gst_pad_chain_data_unchecked (GstPad * pad, gboolean is_buffer, void *data,
4208 GstPadPushCache * cache)
4211 gboolean caps_changed;
4213 gboolean emit_signal;
4215 GST_PAD_STREAM_LOCK (pad);
4217 GST_OBJECT_LOCK (pad);
4218 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4221 caps = gst_pad_data_get_caps (is_buffer, data);
4222 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4224 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4225 GST_OBJECT_UNLOCK (pad);
4227 /* see if the signal should be emited, we emit before caps nego as
4228 * we might drop the buffer and do capsnego for nothing. */
4229 if (G_UNLIKELY (emit_signal)) {
4231 if (G_LIKELY (is_buffer)) {
4232 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (data)))
4235 /* chain all groups in the buffer list one by one to avoid problems with
4236 * buffer probes that push buffers or events */
4241 /* we got a new datatype on the pad, see if it can handle it */
4242 if (G_UNLIKELY (caps_changed)) {
4243 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
4244 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
4245 goto not_negotiated;
4248 /* NOTE: we read the chainfunc unlocked.
4249 * we cannot hold the lock for the pad so we might send
4250 * the data to the wrong function. This is not really a
4251 * problem since functions are assigned at creation time
4252 * and don't change that often... */
4253 if (G_LIKELY (is_buffer)) {
4254 GstPadChainFunction chainfunc;
4256 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
4259 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4260 "calling chainfunction &%s with buffer %" GST_PTR_FORMAT,
4261 GST_DEBUG_FUNCPTR_NAME (chainfunc), GST_BUFFER (data));
4264 cache->peer = gst_object_ref (pad);
4265 cache->caps = caps ? gst_caps_ref (caps) : NULL;
4268 ret = chainfunc (pad, GST_BUFFER_CAST (data));
4270 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4271 "called chainfunction &%s with buffer %p, returned %s",
4272 GST_DEBUG_FUNCPTR_NAME (chainfunc), data, gst_flow_get_name (ret));
4274 GstPadChainListFunction chainlistfunc;
4276 if (G_UNLIKELY ((chainlistfunc = GST_PAD_CHAINLISTFUNC (pad)) == NULL))
4279 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4280 "calling chainlistfunction &%s",
4281 GST_DEBUG_FUNCPTR_NAME (chainlistfunc));
4283 ret = chainlistfunc (pad, GST_BUFFER_LIST_CAST (data));
4285 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4286 "called chainlistfunction &%s, returned %s",
4287 GST_DEBUG_FUNCPTR_NAME (chainlistfunc), gst_flow_get_name (ret));
4290 GST_PAD_STREAM_UNLOCK (pad);
4296 GstBufferList *list;
4297 GstBufferListIterator *it;
4300 GST_PAD_STREAM_UNLOCK (pad);
4302 GST_INFO_OBJECT (pad, "chaining each group in list as a merged buffer");
4304 list = GST_BUFFER_LIST_CAST (data);
4305 it = gst_buffer_list_iterate (list);
4307 if (gst_buffer_list_iterator_next_group (it)) {
4309 group = gst_buffer_list_iterator_merge_group (it);
4310 if (group == NULL) {
4311 group = gst_buffer_new ();
4312 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining empty group");
4314 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining group");
4316 ret = gst_pad_chain_data_unchecked (pad, TRUE, group, NULL);
4317 } while (ret == GST_FLOW_OK && gst_buffer_list_iterator_next_group (it));
4319 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining empty group");
4320 ret = gst_pad_chain_data_unchecked (pad, TRUE, gst_buffer_new (), NULL);
4323 gst_buffer_list_iterator_free (it);
4324 gst_buffer_list_unref (list);
4332 gst_pad_data_unref (is_buffer, data);
4333 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4334 "pushing, but pad was flushing");
4335 GST_OBJECT_UNLOCK (pad);
4336 GST_PAD_STREAM_UNLOCK (pad);
4337 return GST_FLOW_WRONG_STATE;
4341 gst_pad_data_unref (is_buffer, data);
4342 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
4343 GST_PAD_STREAM_UNLOCK (pad);
4348 gst_pad_data_unref (is_buffer, data);
4349 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4350 "pushing data but pad did not accept");
4351 GST_PAD_STREAM_UNLOCK (pad);
4352 return GST_FLOW_NOT_NEGOTIATED;
4356 gst_pad_data_unref (is_buffer, data);
4357 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4358 "pushing, but not chainhandler");
4359 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
4360 ("push on pad %s:%s but it has no chainfunction",
4361 GST_DEBUG_PAD_NAME (pad)));
4362 GST_PAD_STREAM_UNLOCK (pad);
4363 return GST_FLOW_NOT_SUPPORTED;
4369 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4370 * @buffer: (transfer full): the #GstBuffer to send, return GST_FLOW_ERROR
4373 * Chain a buffer to @pad.
4375 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
4377 * If the caps on @buffer are different from the current caps on @pad, this
4378 * function will call any setcaps function (see gst_pad_set_setcaps_function())
4379 * installed on @pad. If the new caps are not acceptable for @pad, this
4380 * function returns #GST_FLOW_NOT_NEGOTIATED.
4382 * The function proceeds calling the chain function installed on @pad (see
4383 * gst_pad_set_chain_function()) and the return value of that function is
4384 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
4387 * In all cases, success or failure, the caller loses its reference to @buffer
4388 * after calling this function.
4390 * Returns: a #GstFlowReturn from the pad.
4395 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
4397 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4398 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4399 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
4401 return gst_pad_chain_data_unchecked (pad, TRUE, buffer, NULL);
4405 * gst_pad_chain_list:
4406 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4407 * @list: (transfer full): the #GstBufferList to send, return GST_FLOW_ERROR
4410 * Chain a bufferlist to @pad.
4412 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
4414 * If the caps on the first buffer of @list are different from the current
4415 * caps on @pad, this function will call any setcaps function
4416 * (see gst_pad_set_setcaps_function()) installed on @pad. If the new caps
4417 * are not acceptable for @pad, this function returns #GST_FLOW_NOT_NEGOTIATED.
4419 * The function proceeds calling the chainlist function installed on @pad (see
4420 * gst_pad_set_chain_list_function()) and the return value of that function is
4421 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
4422 * chainlist function.
4424 * In all cases, success or failure, the caller loses its reference to @list
4425 * after calling this function.
4429 * Returns: a #GstFlowReturn from the pad.
4434 gst_pad_chain_list (GstPad * pad, GstBufferList * list)
4436 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4437 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4438 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
4440 return gst_pad_chain_data_unchecked (pad, FALSE, list, NULL);
4443 static GstFlowReturn
4444 gst_pad_push_data (GstPad * pad, gboolean is_buffer, void *data,
4445 GstPadPushCache * cache)
4450 gboolean caps_changed;
4452 GST_OBJECT_LOCK (pad);
4454 /* FIXME: this check can go away; pad_set_blocked could be implemented with
4455 * probes completely or probes with an extended pad block. */
4456 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
4457 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
4460 /* we emit signals on the pad arg, the peer will have a chance to
4461 * emit in the _chain() function */
4462 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
4464 /* unlock before emitting */
4465 GST_OBJECT_UNLOCK (pad);
4467 if (G_LIKELY (is_buffer)) {
4468 /* if the signal handler returned FALSE, it means we should just drop the
4470 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (data)))
4473 /* push all buffers in the list */
4476 GST_OBJECT_LOCK (pad);
4479 /* Before pushing the buffer to the peer pad, ensure that caps
4480 * are set on this pad */
4481 caps = gst_pad_data_get_caps (is_buffer, data);
4482 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4484 /* we got a new datatype from the pad, it had better handle it */
4485 if (G_UNLIKELY (caps_changed)) {
4486 /* unlock before setting */
4487 GST_OBJECT_UNLOCK (pad);
4488 GST_DEBUG_OBJECT (pad,
4489 "caps changed from %" GST_PTR_FORMAT " to %p %" GST_PTR_FORMAT,
4490 GST_PAD_CAPS (pad), caps, caps);
4491 if (G_UNLIKELY (!gst_pad_set_caps (pad, caps)))
4492 goto not_negotiated;
4493 GST_OBJECT_LOCK (pad);
4496 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4499 /* take ref to peer pad before releasing the lock */
4500 gst_object_ref (peer);
4501 GST_OBJECT_UNLOCK (pad);
4503 ret = gst_pad_chain_data_unchecked (peer, is_buffer, data, cache);
4505 gst_object_unref (peer);
4511 GstBufferList *list;
4512 GstBufferListIterator *it;
4515 GST_INFO_OBJECT (pad, "pushing each group in list as a merged buffer");
4517 list = GST_BUFFER_LIST_CAST (data);
4518 it = gst_buffer_list_iterate (list);
4520 if (gst_buffer_list_iterator_next_group (it)) {
4522 group = gst_buffer_list_iterator_merge_group (it);
4523 if (group == NULL) {
4524 group = gst_buffer_new ();
4525 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing empty group");
4527 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing group");
4529 ret = gst_pad_push_data (pad, TRUE, group, NULL);
4530 } while (ret == GST_FLOW_OK && gst_buffer_list_iterator_next_group (it));
4532 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing empty group");
4533 ret = gst_pad_push_data (pad, TRUE, gst_buffer_new (), NULL);
4536 gst_buffer_list_iterator_free (it);
4537 gst_buffer_list_unref (list);
4542 /* ERROR recovery here */
4545 gst_pad_data_unref (is_buffer, data);
4546 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
4547 GST_OBJECT_UNLOCK (pad);
4552 gst_pad_data_unref (is_buffer, data);
4553 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
4558 gst_pad_data_unref (is_buffer, data);
4559 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4560 "pushing, but it was not linked");
4561 GST_OBJECT_UNLOCK (pad);
4562 return GST_FLOW_NOT_LINKED;
4566 gst_pad_data_unref (is_buffer, data);
4567 GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
4568 "element pushed data then refused to accept the caps");
4569 return GST_FLOW_NOT_NEGOTIATED;
4573 static inline GstPadPushCache *
4574 pad_take_cache (GstPad * pad, gpointer * cache_ptr)
4576 GstPadPushCache *cache;
4578 /* try to get the cached data */
4580 cache = g_atomic_pointer_get (cache_ptr);
4581 /* now try to replace the pointer with NULL to mark that we are busy
4583 } while (!g_atomic_pointer_compare_and_exchange (cache_ptr, cache, NULL));
4585 /* we could have a leftover invalid entry */
4586 if (G_UNLIKELY (cache == PAD_CACHE_INVALID))
4593 pad_free_cache (GstPadPushCache * cache)
4595 gst_object_unref (cache->peer);
4597 gst_caps_unref (cache->caps);
4598 g_slice_free (GstPadPushCache, cache);
4602 pad_put_cache (GstPad * pad, GstPadPushCache * cache, gpointer * cache_ptr)
4605 if (!g_atomic_pointer_compare_and_exchange (cache_ptr, NULL, cache)) {
4606 /* something changed, clean up our cache */
4607 pad_free_cache (cache);
4611 /* must be called with the pad lock */
4613 _priv_gst_pad_invalidate_cache (GstPad * pad)
4615 GstPadPushCache *cache;
4616 gpointer *cache_ptr;
4618 GST_LOG_OBJECT (pad, "Invalidating pad cache");
4620 /* we hold the pad lock here so we can get the peer and it stays
4621 * alive during this call */
4622 if (GST_PAD_IS_SINK (pad)) {
4623 if (!(pad = GST_PAD_PEER (pad)))
4627 cache_ptr = (gpointer *) & pad->abidata.ABI.priv->cache_ptr;
4629 /* try to get the cached data */
4631 cache = g_atomic_pointer_get (cache_ptr);
4632 /* now try to replace the pointer with INVALID. If nothing is busy with this
4633 * caps, we get the cache and clean it up. If something is busy, we replace
4634 * with INVALID so that when the function finishes and tries to put the
4635 * cache back, it'll fail and cleanup */
4636 } while (!g_atomic_pointer_compare_and_exchange (cache_ptr, cache,
4637 PAD_CACHE_INVALID));
4639 if (G_LIKELY (cache && cache != PAD_CACHE_INVALID))
4640 pad_free_cache (cache);
4645 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
4646 * @buffer: (transfer full): the #GstBuffer to push returns GST_FLOW_ERROR
4649 * Pushes a buffer to the peer of @pad.
4651 * This function will call an installed pad block before triggering any
4652 * installed pad probes.
4654 * If the caps on @buffer are different from the currently configured caps on
4655 * @pad, this function will call any installed setcaps function on @pad (see
4656 * gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
4657 * format, this function returns #GST_FLOW_NOT_NEGOTIATED.
4659 * The function proceeds calling gst_pad_chain() on the peer pad and returns
4660 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
4663 * In all cases, success or failure, the caller loses its reference to @buffer
4664 * after calling this function.
4666 * Returns: a #GstFlowReturn from the peer pad.
4671 gst_pad_push (GstPad * pad, GstBuffer * buffer)
4673 GstPadPushCache *cache;
4675 gpointer *cache_ptr;
4679 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4680 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4681 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
4683 cache_ptr = (gpointer *) & pad->abidata.ABI.priv->cache_ptr;
4685 cache = pad_take_cache (pad, cache_ptr);
4687 if (G_UNLIKELY (cache == NULL))
4691 caps = GST_BUFFER_CAPS (buffer);
4692 if (G_UNLIKELY (caps && caps != cache->caps)) {
4693 pad_free_cache (cache);
4699 GST_PAD_STREAM_LOCK (peer);
4700 if (G_UNLIKELY (g_atomic_pointer_get (cache_ptr) == PAD_CACHE_INVALID))
4703 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4704 "calling chainfunction &%s with buffer %" GST_PTR_FORMAT,
4705 GST_DEBUG_FUNCPTR_NAME (GST_PAD_CHAINFUNC (peer)), buffer);
4707 ret = GST_PAD_CHAINFUNC (peer) (peer, buffer);
4709 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4710 "called chainfunction &%s with buffer %p, returned %s",
4711 GST_DEBUG_FUNCPTR_NAME (GST_PAD_CHAINFUNC (peer)), buffer,
4712 gst_flow_get_name (ret));
4714 GST_PAD_STREAM_UNLOCK (peer);
4716 pad_put_cache (pad, cache, cache_ptr);
4723 GstPadPushCache scache = { NULL, };
4725 GST_LOG_OBJECT (pad, "Taking slow path");
4727 ret = gst_pad_push_data (pad, TRUE, buffer, &scache);
4730 GstPadPushCache *ncache;
4732 GST_LOG_OBJECT (pad, "Caching push data");
4734 /* make cache structure */
4735 ncache = g_slice_new (GstPadPushCache);
4738 pad_put_cache (pad, ncache, cache_ptr);
4744 GST_PAD_STREAM_UNLOCK (peer);
4745 pad_free_cache (cache);
4751 * gst_pad_push_list:
4752 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
4753 * @list: (transfer full): the #GstBufferList to push returns GST_FLOW_ERROR
4756 * Pushes a buffer list to the peer of @pad.
4758 * This function will call an installed pad block before triggering any
4759 * installed pad probes.
4761 * If the caps on the first buffer in the first group of @list are different
4762 * from the currently configured caps on @pad, this function will call any
4763 * installed setcaps function on @pad (see gst_pad_set_setcaps_function()). In
4764 * case of failure to renegotiate the new format, this function returns
4765 * #GST_FLOW_NOT_NEGOTIATED.
4767 * If there are any probes installed on @pad every group of the buffer list
4768 * will be merged into a normal #GstBuffer and pushed via gst_pad_push and the
4769 * buffer list will be unreffed.
4771 * The function proceeds calling the chain function on the peer pad and returns
4772 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
4773 * be returned. If the peer pad does not have any installed chainlist function
4774 * every group buffer of the list will be merged into a normal #GstBuffer and
4775 * chained via gst_pad_chain().
4777 * In all cases, success or failure, the caller loses its reference to @list
4778 * after calling this function.
4780 * Returns: a #GstFlowReturn from the peer pad.
4787 gst_pad_push_list (GstPad * pad, GstBufferList * list)
4790 GstPadPushCache *cache;
4792 gpointer *cache_ptr;
4796 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4797 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4798 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
4800 cache_ptr = (gpointer *) & pad->abidata.ABI.priv->cache_ptr;
4802 cache = pad_take_cache (pad, cache_ptr);
4804 if (G_UNLIKELY (cache == NULL))
4808 if ((buf = gst_buffer_list_get (list, 0, 0)))
4809 caps = GST_BUFFER_CAPS (buf);
4813 if (G_UNLIKELY (caps && caps != cache->caps)) {
4814 pad_free_cache (cache);
4820 GST_PAD_STREAM_LOCK (peer);
4821 if (G_UNLIKELY (g_atomic_pointer_get (cache_ptr) == PAD_CACHE_INVALID))
4824 ret = GST_PAD_CHAINLISTFUNC (peer) (peer, list);
4826 GST_PAD_STREAM_UNLOCK (peer);
4828 pad_put_cache (pad, cache, cache_ptr);
4835 GstPadPushCache scache = { NULL, };
4837 GST_LOG_OBJECT (pad, "Taking slow path");
4839 ret = gst_pad_push_data (pad, FALSE, list, &scache);
4842 GstPadPushCache *ncache;
4844 GST_LOG_OBJECT (pad, "Caching push data");
4846 /* make cache structure */
4847 ncache = g_slice_new (GstPadPushCache);
4850 pad_put_cache (pad, ncache, cache_ptr);
4856 GST_PAD_STREAM_UNLOCK (peer);
4857 pad_free_cache (cache);
4863 * gst_pad_check_pull_range:
4864 * @pad: a sink #GstPad.
4866 * Checks if a gst_pad_pull_range() can be performed on the peer
4867 * source pad. This function is used by plugins that want to check
4868 * if they can use random access on the peer source pad.
4870 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
4871 * if it needs to perform some logic to determine if pull_range is
4874 * Returns: a gboolean with the result.
4879 gst_pad_check_pull_range (GstPad * pad)
4883 GstPadCheckGetRangeFunction checkgetrangefunc;
4885 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4887 GST_OBJECT_LOCK (pad);
4888 if (!GST_PAD_IS_SINK (pad))
4889 goto wrong_direction;
4891 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4894 gst_object_ref (peer);
4895 GST_OBJECT_UNLOCK (pad);
4897 /* see note in above function */
4898 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
4899 /* FIXME, kindoff ghetto */
4900 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
4901 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4902 "no checkgetrangefunc, assuming %d", ret);
4904 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4905 "calling checkgetrangefunc %s of peer pad %s:%s",
4906 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
4908 ret = checkgetrangefunc (peer);
4911 gst_object_unref (peer);
4915 /* ERROR recovery here */
4918 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4919 "checking pull range, but pad must be a sinkpad");
4920 GST_OBJECT_UNLOCK (pad);
4925 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4926 "checking pull range, but it was not linked");
4927 GST_OBJECT_UNLOCK (pad);
4932 static GstFlowReturn
4933 gst_pad_get_range_unchecked (GstPad * pad, guint64 offset, guint size,
4934 GstBuffer ** buffer)
4937 GstPadGetRangeFunction getrangefunc;
4938 gboolean emit_signal;
4940 gboolean caps_changed;
4942 GST_PAD_STREAM_LOCK (pad);
4944 GST_OBJECT_LOCK (pad);
4945 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4948 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4949 GST_OBJECT_UNLOCK (pad);
4951 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
4954 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4955 "calling getrangefunc %s, offset %"
4956 G_GUINT64_FORMAT ", size %u",
4957 GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
4959 ret = getrangefunc (pad, offset, size, buffer);
4961 /* can only fire the signal if we have a valid buffer */
4962 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
4963 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
4967 GST_PAD_STREAM_UNLOCK (pad);
4969 if (G_UNLIKELY (ret != GST_FLOW_OK))
4970 goto get_range_failed;
4972 GST_OBJECT_LOCK (pad);
4973 /* Before pushing the buffer to the peer pad, ensure that caps
4974 * are set on this pad */
4975 caps = GST_BUFFER_CAPS (*buffer);
4976 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4977 GST_OBJECT_UNLOCK (pad);
4979 if (G_UNLIKELY (caps_changed)) {
4980 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
4981 /* this should usually work because the element produced the buffer */
4982 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
4983 goto not_negotiated;
4990 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4991 "pulling range, but pad was flushing");
4992 GST_OBJECT_UNLOCK (pad);
4993 GST_PAD_STREAM_UNLOCK (pad);
4994 return GST_FLOW_WRONG_STATE;
4998 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
4999 ("pullrange on pad %s:%s but it has no getrangefunction",
5000 GST_DEBUG_PAD_NAME (pad)));
5001 GST_PAD_STREAM_UNLOCK (pad);
5002 return GST_FLOW_NOT_SUPPORTED;
5006 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
5007 "Dropping data after FALSE probe return");
5008 GST_PAD_STREAM_UNLOCK (pad);
5009 gst_buffer_unref (*buffer);
5011 return GST_FLOW_UNEXPECTED;
5016 GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
5017 (ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
5018 pad, "getrange failed, flow: %s", gst_flow_get_name (ret));
5023 gst_buffer_unref (*buffer);
5025 GST_CAT_WARNING_OBJECT (GST_CAT_SCHEDULING, pad,
5026 "getrange returned buffer of unaccaptable caps");
5027 return GST_FLOW_NOT_NEGOTIATED;
5032 * gst_pad_get_range:
5033 * @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
5034 * @offset: The start offset of the buffer
5035 * @size: The length of the buffer
5036 * @buffer: (out callee-allocates): a pointer to hold the #GstBuffer,
5037 * returns #GST_FLOW_ERROR if %NULL.
5039 * When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
5040 * immediately and @buffer is %NULL.
5042 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
5043 * description of a getrange function. If @pad has no getrange function
5044 * installed (see gst_pad_set_getrange_function()) this function returns
5045 * #GST_FLOW_NOT_SUPPORTED.
5047 * This is a lowlevel function. Usualy gst_pad_pull_range() is used.
5049 * Returns: a #GstFlowReturn from the pad.
5054 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
5055 GstBuffer ** buffer)
5057 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
5058 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
5059 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
5061 return gst_pad_get_range_unchecked (pad, offset, size, buffer);
5065 * gst_pad_pull_range:
5066 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
5067 * @offset: The start offset of the buffer
5068 * @size: The length of the buffer
5069 * @buffer: (out callee-allocates): a pointer to hold the #GstBuffer, returns
5070 * GST_FLOW_ERROR if %NULL.
5072 * Pulls a @buffer from the peer pad.
5074 * This function will first trigger the pad block signal if it was
5077 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
5078 * function returns the result of gst_pad_get_range() on the peer pad.
5079 * See gst_pad_get_range() for a list of return values and for the
5080 * semantics of the arguments of this function.
5082 * @buffer's caps must either be unset or the same as what is already
5083 * configured on @pad. Renegotiation within a running pull-mode pipeline is not
5086 * Returns: a #GstFlowReturn from the peer pad.
5087 * When this function returns #GST_FLOW_OK, @buffer will contain a valid
5088 * #GstBuffer that should be freed with gst_buffer_unref() after usage.
5089 * @buffer may not be used or freed when any other return value than
5090 * #GST_FLOW_OK is returned.
5095 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
5096 GstBuffer ** buffer)
5100 gboolean emit_signal;
5102 gboolean caps_changed;
5104 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
5105 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
5106 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
5108 GST_OBJECT_LOCK (pad);
5110 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
5111 handle_pad_block (pad);
5113 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
5116 /* signal emision for the pad, peer has chance to emit when
5117 * we call _get_range() */
5118 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
5120 gst_object_ref (peer);
5121 GST_OBJECT_UNLOCK (pad);
5123 ret = gst_pad_get_range_unchecked (peer, offset, size, buffer);
5125 gst_object_unref (peer);
5127 if (G_UNLIKELY (ret != GST_FLOW_OK))
5128 goto pull_range_failed;
5130 /* can only fire the signal if we have a valid buffer */
5131 if (G_UNLIKELY (emit_signal)) {
5132 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
5136 GST_OBJECT_LOCK (pad);
5137 /* Before pushing the buffer to the peer pad, ensure that caps
5138 * are set on this pad */
5139 caps = GST_BUFFER_CAPS (*buffer);
5140 caps_changed = caps && caps != GST_PAD_CAPS (pad);
5141 GST_OBJECT_UNLOCK (pad);
5143 /* we got a new datatype on the pad, see if it can handle it */
5144 if (G_UNLIKELY (caps_changed)) {
5145 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
5146 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
5147 goto not_negotiated;
5151 /* ERROR recovery here */
5154 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
5155 "pulling range, but it was not linked");
5156 GST_OBJECT_UNLOCK (pad);
5157 return GST_FLOW_NOT_LINKED;
5162 GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
5163 (ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
5164 pad, "pullrange failed, flow: %s", gst_flow_get_name (ret));
5169 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
5170 "Dropping data after FALSE probe return");
5171 gst_buffer_unref (*buffer);
5173 return GST_FLOW_UNEXPECTED;
5177 gst_buffer_unref (*buffer);
5179 GST_CAT_WARNING_OBJECT (GST_CAT_SCHEDULING, pad,
5180 "pullrange returned buffer of different caps");
5181 return GST_FLOW_NOT_NEGOTIATED;
5186 * gst_pad_push_event:
5187 * @pad: a #GstPad to push the event to.
5188 * @event: (transfer full): the #GstEvent to send to the pad.
5190 * Sends the event to the peer of the given pad. This function is
5191 * mainly used by elements to send events to their peer
5194 * This function takes owership of the provided event so you should
5195 * gst_event_ref() it if you want to reuse the event after this call.
5197 * Returns: TRUE if the event was handled.
5202 gst_pad_push_event (GstPad * pad, GstEvent * event)
5207 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5208 g_return_val_if_fail (event != NULL, FALSE);
5209 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
5211 GST_LOG_OBJECT (pad, "event: %s", GST_EVENT_TYPE_NAME (event));
5213 GST_OBJECT_LOCK (pad);
5215 /* Two checks to be made:
5216 * . (un)set the FLUSHING flag for flushing events,
5217 * . handle pad blocking */
5218 switch (GST_EVENT_TYPE (event)) {
5219 case GST_EVENT_FLUSH_START:
5220 _priv_gst_pad_invalidate_cache (pad);
5221 GST_PAD_SET_FLUSHING (pad);
5223 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
5224 /* flush start will have set the FLUSHING flag and will then
5225 * unlock all threads doing a GCond wait on the blocking pad. This
5226 * will typically unblock the STREAMING thread blocked on a pad. */
5227 GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-start, "
5228 "doing block signal.");
5229 GST_PAD_BLOCK_BROADCAST (pad);
5233 case GST_EVENT_FLUSH_STOP:
5234 GST_PAD_UNSET_FLUSHING (pad);
5236 /* if we are blocked, flush away the FLUSH_STOP event */
5237 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
5238 GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-stop");
5243 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
5244 /* block the event as long as the pad is blocked */
5245 if (handle_pad_block (pad) != GST_FLOW_OK)
5251 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
5252 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
5253 GST_EVENT_SRC (event) = gst_object_ref (pad);
5256 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
5257 GST_OBJECT_UNLOCK (pad);
5259 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
5262 GST_OBJECT_LOCK (pad);
5264 peerpad = GST_PAD_PEER (pad);
5265 if (peerpad == NULL)
5268 GST_LOG_OBJECT (pad,
5269 "sending event %s (%" GST_PTR_FORMAT ") to peerpad %" GST_PTR_FORMAT,
5270 GST_EVENT_TYPE_NAME (event), event, peerpad);
5271 gst_object_ref (peerpad);
5272 GST_OBJECT_UNLOCK (pad);
5274 result = gst_pad_send_event (peerpad, event);
5276 /* Note: we gave away ownership of the event at this point */
5277 GST_LOG_OBJECT (pad, "sent event to peerpad %" GST_PTR_FORMAT ", result %d",
5279 gst_object_unref (peerpad);
5283 /* ERROR handling */
5286 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
5287 gst_event_unref (event);
5292 GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
5293 gst_event_unref (event);
5294 GST_OBJECT_UNLOCK (pad);
5299 GST_DEBUG_OBJECT (pad,
5300 "Not forwarding event since we're flushing and blocking");
5301 gst_event_unref (event);
5302 GST_OBJECT_UNLOCK (pad);
5308 * gst_pad_send_event:
5309 * @pad: a #GstPad to send the event to.
5310 * @event: (transfer full): the #GstEvent to send to the pad.
5312 * Sends the event to the pad. This function can be used
5313 * by applications to send events in the pipeline.
5315 * If @pad is a source pad, @event should be an upstream event. If @pad is a
5316 * sink pad, @event should be a downstream event. For example, you would not
5317 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
5318 * Furthermore, some downstream events have to be serialized with data flow,
5319 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
5320 * the event needs to be serialized with data flow, this function will take the
5321 * pad's stream lock while calling its event function.
5323 * To find out whether an event type is upstream, downstream, or downstream and
5324 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
5325 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
5326 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or
5327 * plugin doesn't need to bother itself with this information; the core handles
5328 * all necessary locks and checks.
5330 * This function takes owership of the provided event so you should
5331 * gst_event_ref() it if you want to reuse the event after this call.
5333 * Returns: TRUE if the event was handled.
5336 gst_pad_send_event (GstPad * pad, GstEvent * event)
5338 gboolean result = FALSE;
5339 GstPadEventFunction eventfunc;
5340 gboolean serialized, need_unlock = FALSE;
5342 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5343 g_return_val_if_fail (event != NULL, FALSE);
5345 GST_OBJECT_LOCK (pad);
5346 if (GST_PAD_IS_SINK (pad)) {
5347 if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
5348 goto wrong_direction;
5349 serialized = GST_EVENT_IS_SERIALIZED (event);
5350 } else if (GST_PAD_IS_SRC (pad)) {
5351 if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
5352 goto wrong_direction;
5353 /* events on srcpad never are serialized */
5356 goto unknown_direction;
5358 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
5359 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
5360 GST_EVENT_SRC (event) = gst_object_ref (pad);
5364 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
5365 GST_OBJECT_UNLOCK (pad);
5367 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
5370 GST_OBJECT_LOCK (pad);
5373 switch (GST_EVENT_TYPE (event)) {
5374 case GST_EVENT_FLUSH_START:
5375 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
5376 "have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
5378 /* can't even accept a flush begin event when flushing */
5379 if (GST_PAD_IS_FLUSHING (pad))
5382 _priv_gst_pad_invalidate_cache (pad);
5383 GST_PAD_SET_FLUSHING (pad);
5384 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
5386 case GST_EVENT_FLUSH_STOP:
5387 if (G_LIKELY (GST_PAD_ACTIVATE_MODE (pad) != GST_ACTIVATE_NONE)) {
5388 GST_PAD_UNSET_FLUSHING (pad);
5389 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
5391 GST_OBJECT_UNLOCK (pad);
5392 /* grab stream lock */
5393 GST_PAD_STREAM_LOCK (pad);
5395 GST_OBJECT_LOCK (pad);
5398 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
5399 GST_EVENT_TYPE_NAME (event));
5401 /* make this a little faster, no point in grabbing the lock
5402 * if the pad is already flushing. */
5403 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
5407 /* lock order: STREAM_LOCK, LOCK, recheck flushing. */
5408 GST_OBJECT_UNLOCK (pad);
5409 GST_PAD_STREAM_LOCK (pad);
5411 GST_OBJECT_LOCK (pad);
5412 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
5417 if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
5420 GST_OBJECT_UNLOCK (pad);
5422 result = eventfunc (pad, event);
5425 GST_PAD_STREAM_UNLOCK (pad);
5427 GST_DEBUG_OBJECT (pad, "sent event, result %d", result);
5431 /* ERROR handling */
5434 g_warning ("pad %s:%s sending %s event in wrong direction",
5435 GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
5436 GST_OBJECT_UNLOCK (pad);
5437 gst_event_unref (event);
5442 g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
5443 GST_OBJECT_UNLOCK (pad);
5444 gst_event_unref (event);
5449 g_warning ("pad %s:%s has no event handler, file a bug.",
5450 GST_DEBUG_PAD_NAME (pad));
5451 GST_OBJECT_UNLOCK (pad);
5453 GST_PAD_STREAM_UNLOCK (pad);
5454 gst_event_unref (event);
5459 GST_OBJECT_UNLOCK (pad);
5461 GST_PAD_STREAM_UNLOCK (pad);
5462 GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
5463 "Received event on flushing pad. Discarding");
5464 gst_event_unref (event);
5469 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
5470 gst_event_unref (event);
5476 * gst_pad_set_element_private:
5477 * @pad: the #GstPad to set the private data of.
5478 * @priv: The private data to attach to the pad.
5480 * Set the given private data gpointer on the pad.
5481 * This function can only be used by the element that owns the pad.
5482 * No locking is performed in this function.
5485 gst_pad_set_element_private (GstPad * pad, gpointer priv)
5487 pad->element_private = priv;
5491 * gst_pad_get_element_private:
5492 * @pad: the #GstPad to get the private data of.
5494 * Gets the private data of a pad.
5495 * No locking is performed in this function.
5497 * Returns: (transfer none): a #gpointer to the private data.
5500 gst_pad_get_element_private (GstPad * pad)
5502 return pad->element_private;
5506 do_stream_status (GstPad * pad, GstStreamStatusType type,
5507 GThread * thread, GstTask * task)
5511 GST_DEBUG_OBJECT (pad, "doing stream-status %d", type);
5513 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (pad)))) {
5514 if (GST_IS_ELEMENT (parent)) {
5515 GstMessage *message;
5516 GValue value = { 0 };
5518 if (type == GST_STREAM_STATUS_TYPE_ENTER) {
5519 gchar *tname, *ename, *pname;
5521 /* create a good task name */
5522 ename = gst_element_get_name (parent);
5523 pname = gst_pad_get_name (pad);
5524 tname = g_strdup_printf ("%s:%s", ename, pname);
5528 gst_object_set_name (GST_OBJECT_CAST (task), tname);
5532 message = gst_message_new_stream_status (GST_OBJECT_CAST (pad),
5535 g_value_init (&value, GST_TYPE_TASK);
5536 g_value_set_object (&value, task);
5537 gst_message_set_stream_status_object (message, &value);
5538 g_value_unset (&value);
5540 GST_DEBUG_OBJECT (pad, "posting stream-status %d", type);
5541 gst_element_post_message (parent, message);
5543 gst_object_unref (parent);
5548 pad_enter_thread (GstTask * task, GThread * thread, gpointer user_data)
5550 do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_ENTER,
5555 pad_leave_thread (GstTask * task, GThread * thread, gpointer user_data)
5557 do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_LEAVE,
5561 static GstTaskThreadCallbacks thr_callbacks = {
5567 * gst_pad_start_task:
5568 * @pad: the #GstPad to start the task of
5569 * @func: the task function to call
5570 * @data: data passed to the task function
5572 * Starts a task that repeatedly calls @func with @data. This function
5573 * is mostly used in pad activation functions to start the dataflow.
5574 * The #GST_PAD_STREAM_LOCK of @pad will automatically be acquired
5575 * before @func is called.
5577 * Returns: a %TRUE if the task could be started.
5580 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
5585 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5586 g_return_val_if_fail (func != NULL, FALSE);
5588 GST_DEBUG_OBJECT (pad, "start task");
5590 GST_OBJECT_LOCK (pad);
5591 task = GST_PAD_TASK (pad);
5593 task = gst_task_create (func, data);
5594 gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
5595 gst_task_set_thread_callbacks (task, &thr_callbacks, pad, NULL);
5596 GST_DEBUG_OBJECT (pad, "created task");
5597 GST_PAD_TASK (pad) = task;
5598 gst_object_ref (task);
5599 /* release lock to post the message */
5600 GST_OBJECT_UNLOCK (pad);
5602 do_stream_status (pad, GST_STREAM_STATUS_TYPE_CREATE, NULL, task);
5604 gst_object_unref (task);
5606 GST_OBJECT_LOCK (pad);
5607 /* nobody else is supposed to have changed the pad now */
5608 if (GST_PAD_TASK (pad) != task)
5609 goto concurrent_stop;
5611 res = gst_task_set_state (task, GST_TASK_STARTED);
5612 GST_OBJECT_UNLOCK (pad);
5619 GST_OBJECT_UNLOCK (pad);
5625 * gst_pad_pause_task:
5626 * @pad: the #GstPad to pause the task of
5628 * Pause the task of @pad. This function will also wait until the
5629 * function executed by the task is finished if this function is not
5630 * called from the task function.
5632 * Returns: a TRUE if the task could be paused or FALSE when the pad
5636 gst_pad_pause_task (GstPad * pad)
5641 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5643 GST_DEBUG_OBJECT (pad, "pause task");
5645 GST_OBJECT_LOCK (pad);
5646 task = GST_PAD_TASK (pad);
5649 res = gst_task_set_state (task, GST_TASK_PAUSED);
5650 GST_OBJECT_UNLOCK (pad);
5652 /* wait for task function to finish, this lock is recursive so it does nothing
5653 * when the pause is called from the task itself */
5654 GST_PAD_STREAM_LOCK (pad);
5655 GST_PAD_STREAM_UNLOCK (pad);
5661 GST_DEBUG_OBJECT (pad, "pad has no task");
5662 GST_OBJECT_UNLOCK (pad);
5668 * gst_pad_stop_task:
5669 * @pad: the #GstPad to stop the task of
5671 * Stop the task of @pad. This function will also make sure that the
5672 * function executed by the task will effectively stop if not called
5673 * from the GstTaskFunction.
5675 * This function will deadlock if called from the GstTaskFunction of
5676 * the task. Use gst_task_pause() instead.
5678 * Regardless of whether the pad has a task, the stream lock is acquired and
5679 * released so as to ensure that streaming through this pad has finished.
5681 * Returns: a TRUE if the task could be stopped or FALSE on error.
5684 gst_pad_stop_task (GstPad * pad)
5689 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5691 GST_DEBUG_OBJECT (pad, "stop task");
5693 GST_OBJECT_LOCK (pad);
5694 task = GST_PAD_TASK (pad);
5697 GST_PAD_TASK (pad) = NULL;
5698 res = gst_task_set_state (task, GST_TASK_STOPPED);
5699 GST_OBJECT_UNLOCK (pad);
5701 GST_PAD_STREAM_LOCK (pad);
5702 GST_PAD_STREAM_UNLOCK (pad);
5704 if (!gst_task_join (task))
5707 gst_object_unref (task);
5713 GST_DEBUG_OBJECT (pad, "no task");
5714 GST_OBJECT_UNLOCK (pad);
5716 GST_PAD_STREAM_LOCK (pad);
5717 GST_PAD_STREAM_UNLOCK (pad);
5719 /* this is not an error */
5724 /* this is bad, possibly the application tried to join the task from
5725 * the task's thread. We install the task again so that it will be stopped
5726 * again from the right thread next time hopefully. */
5727 GST_OBJECT_LOCK (pad);
5728 GST_DEBUG_OBJECT (pad, "join failed");
5729 /* we can only install this task if there was no other task */
5730 if (GST_PAD_TASK (pad) == NULL)
5731 GST_PAD_TASK (pad) = task;
5732 GST_OBJECT_UNLOCK (pad);