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 */
104 GstPadChainFunction chainfunc;
107 static GstPadPushCache _pad_cache_invalid = { NULL, };
109 #define PAD_CACHE_INVALID (&_pad_cache_invalid)
111 static void pad_invalidate_cache (GstPad * pad);
113 #define GST_PAD_GET_PRIVATE(obj) \
114 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PAD, GstPadPrivate))
116 #define GST_PAD_CHAINLISTFUNC(pad) ((pad)->abidata.ABI.priv->chainlistfunc)
118 struct _GstPadPrivate
120 GstPadChainListFunction chainlistfunc;
122 GstPadPushCache *cache_ptr;
125 static void gst_pad_dispose (GObject * object);
126 static void gst_pad_finalize (GObject * object);
127 static void gst_pad_set_property (GObject * object, guint prop_id,
128 const GValue * value, GParamSpec * pspec);
129 static void gst_pad_get_property (GObject * object, guint prop_id,
130 GValue * value, GParamSpec * pspec);
132 static GstFlowReturn handle_pad_block (GstPad * pad);
133 static GstCaps *gst_pad_get_caps_unlocked (GstPad * pad);
134 static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
135 static gboolean gst_pad_activate_default (GstPad * pad);
136 static gboolean gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps);
138 #if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
139 #ifdef GST_DISABLE_DEPRECATED
140 #include <libxml/parser.h>
142 static xmlNodePtr gst_pad_save_thyself (GstObject * object, xmlNodePtr parent);
143 void gst_pad_load_and_link (xmlNodePtr self, GstObject * parent);
146 /* Some deprecated stuff that we need inside here for
147 * backwards compatibility */
148 #ifdef GST_DISABLE_DEPRECATED
149 #ifndef GST_REMOVE_DEPRECATED
150 #define GST_PAD_INTLINKFUNC(pad) (GST_PAD_CAST(pad)->intlinkfunc)
151 GList *gst_pad_get_internal_links_default (GstPad * pad);
155 static GstObjectClass *parent_class = NULL;
156 static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
158 static GParamSpec *pspec_caps = NULL;
160 /* quarks for probe signals */
161 static GQuark buffer_quark;
162 static GQuark event_quark;
171 static GstFlowQuarks flow_quarks[] = {
172 {GST_FLOW_CUSTOM_SUCCESS, "custom-success", 0},
173 {GST_FLOW_RESEND, "resend", 0},
174 {GST_FLOW_OK, "ok", 0},
175 {GST_FLOW_NOT_LINKED, "not-linked", 0},
176 {GST_FLOW_WRONG_STATE, "wrong-state", 0},
177 {GST_FLOW_UNEXPECTED, "unexpected", 0},
178 {GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
179 {GST_FLOW_ERROR, "error", 0},
180 {GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
181 {GST_FLOW_CUSTOM_ERROR, "custom-error", 0}
186 * @ret: a #GstFlowReturn to get the name of.
188 * Gets a string representing the given flow return.
190 * Returns: a static string with the name of the flow return.
192 G_CONST_RETURN gchar *
193 gst_flow_get_name (GstFlowReturn ret)
197 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
199 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
200 if (ret == flow_quarks[i].ret)
201 return flow_quarks[i].name;
208 * @ret: a #GstFlowReturn to get the quark of.
210 * Get the unique quark for the given GstFlowReturn.
212 * Returns: the quark associated with the flow return or 0 if an
213 * invalid return was specified.
216 gst_flow_to_quark (GstFlowReturn ret)
220 ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
222 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
223 if (ret == flow_quarks[i].ret)
224 return flow_quarks[i].quark;
233 buffer_quark = g_quark_from_static_string ("buffer"); \
234 event_quark = g_quark_from_static_string ("event"); \
236 for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) { \
237 flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name); \
240 GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW", \
241 GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads"); \
244 G_DEFINE_TYPE_WITH_CODE (GstPad, gst_pad, GST_TYPE_OBJECT, _do_init);
247 _gst_do_pass_data_accumulator (GSignalInvocationHint * ihint,
248 GValue * return_accu, const GValue * handler_return, gpointer dummy)
250 gboolean ret = g_value_get_boolean (handler_return);
252 GST_DEBUG ("accumulated %d", ret);
253 g_value_set_boolean (return_accu, ret);
259 default_have_data (GstPad * pad, GstMiniObject * o)
265 gst_pad_class_init (GstPadClass * klass)
267 GObjectClass *gobject_class;
268 GstObjectClass *gstobject_class;
270 gobject_class = G_OBJECT_CLASS (klass);
271 gstobject_class = GST_OBJECT_CLASS (klass);
273 g_type_class_add_private (klass, sizeof (GstPadPrivate));
275 parent_class = g_type_class_peek_parent (klass);
277 gobject_class->dispose = gst_pad_dispose;
278 gobject_class->finalize = gst_pad_finalize;
279 gobject_class->set_property = gst_pad_set_property;
280 gobject_class->get_property = gst_pad_get_property;
284 * @pad: the pad that emitted the signal
285 * @peer: the peer pad that has been connected
287 * Signals that a pad has been linked to the peer pad.
289 gst_pad_signals[PAD_LINKED] =
290 g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
291 G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
292 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
295 * @pad: the pad that emitted the signal
296 * @peer: the peer pad that has been disconnected
298 * Signals that a pad has been unlinked from the peer pad.
300 gst_pad_signals[PAD_UNLINKED] =
301 g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
302 G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
303 gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_PAD);
305 * GstPad::request-link:
306 * @pad: the pad that emitted the signal
307 * @peer: the peer pad for which a connection is requested
309 * Signals that a pad connection has been requested.
311 gst_pad_signals[PAD_REQUEST_LINK] =
312 g_signal_new ("request-link", G_TYPE_FROM_CLASS (klass),
313 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstPadClass, request_link), NULL,
314 NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 0);
318 * @pad: the pad that emitted the signal
319 * @mini_obj: new data
321 * Signals that new data is available on the pad. This signal is used
322 * internally for implementing pad probes.
323 * See gst_pad_add_*_probe functions.
325 * Returns: %TRUE to keep the data, %FALSE to drop it
327 gst_pad_signals[PAD_HAVE_DATA] =
328 g_signal_new ("have-data", G_TYPE_FROM_CLASS (klass),
329 G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
330 G_STRUCT_OFFSET (GstPadClass, have_data),
331 _gst_do_pass_data_accumulator,
332 NULL, gst_marshal_BOOLEAN__POINTER, G_TYPE_BOOLEAN, 1,
333 GST_TYPE_MINI_OBJECT);
335 pspec_caps = g_param_spec_boxed ("caps", "Caps",
336 "The capabilities of the pad", GST_TYPE_CAPS,
337 G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
338 g_object_class_install_property (gobject_class, PAD_PROP_CAPS, pspec_caps);
340 g_object_class_install_property (gobject_class, PAD_PROP_DIRECTION,
341 g_param_spec_enum ("direction", "Direction", "The direction of the pad",
342 GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
343 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
344 /* FIXME, Make G_PARAM_CONSTRUCT_ONLY when we fix ghostpads. */
345 g_object_class_install_property (gobject_class, PAD_PROP_TEMPLATE,
346 g_param_spec_object ("template", "Template",
347 "The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
348 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
350 #if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
351 gstobject_class->save_thyself =
352 ((gpointer (*)(GstObject * object,
353 gpointer self)) * GST_DEBUG_FUNCPTR (gst_pad_save_thyself));
355 gstobject_class->path_string_separator = ".";
357 /* Register common function pointer descriptions */
358 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_activate_default);
359 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_event_default);
360 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_query_types_default);
361 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_query_default);
362 #ifndef GST_REMOVE_DEPRECATED
363 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_get_internal_links_default);
365 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_iterate_internal_links_default);
366 GST_DEBUG_REGISTER_FUNCPTR (gst_pad_acceptcaps_default);
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) = 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: 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: 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: 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 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 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 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: 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.
1036 * Returns: TRUE if the pad could be blocked. This function can fail if the
1037 * wrong parameters were passed or the pad was already in the requested state.
1044 gst_pad_set_blocked_async_full (GstPad * pad, gboolean blocked,
1045 GstPadBlockCallback callback, gpointer user_data,
1046 GDestroyNotify destroy_data)
1048 gboolean was_blocked = FALSE;
1050 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1052 GST_OBJECT_LOCK (pad);
1054 was_blocked = GST_PAD_IS_BLOCKED (pad);
1056 if (G_UNLIKELY (was_blocked == blocked))
1057 goto had_right_state;
1060 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocking pad");
1062 pad_invalidate_cache (pad);
1063 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKED);
1065 if (pad->block_destroy_data && pad->block_data)
1066 pad->block_destroy_data (pad->block_data);
1068 pad->block_callback = callback;
1069 pad->block_data = user_data;
1070 pad->block_destroy_data = destroy_data;
1071 pad->abidata.ABI.block_callback_called = FALSE;
1073 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for block");
1074 GST_PAD_BLOCK_WAIT (pad);
1075 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "blocked");
1078 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocking pad");
1080 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKED);
1082 if (pad->block_destroy_data && pad->block_data)
1083 pad->block_destroy_data (pad->block_data);
1085 pad->block_callback = callback;
1086 pad->block_data = user_data;
1087 pad->block_destroy_data = destroy_data;
1088 pad->abidata.ABI.block_callback_called = FALSE;
1090 GST_PAD_BLOCK_BROADCAST (pad);
1092 /* no callback, wait for the unblock to happen */
1093 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "waiting for unblock");
1094 GST_PAD_BLOCK_WAIT (pad);
1095 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "unblocked");
1098 GST_OBJECT_UNLOCK (pad);
1104 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
1105 "pad was in right state (%d)", was_blocked);
1106 GST_OBJECT_UNLOCK (pad);
1113 * gst_pad_set_blocked_async:
1114 * @pad: the #GstPad to block or unblock
1115 * @blocked: boolean indicating whether the pad should be blocked or unblocked
1116 * @callback: #GstPadBlockCallback that will be called when the
1117 * operation succeeds
1118 * @user_data: user data passed to the callback
1120 * Blocks or unblocks the dataflow on a pad. The provided callback
1121 * is called when the operation succeeds; this happens right before the next
1122 * attempt at pushing a buffer on the pad.
1124 * This can take a while as the pad can only become blocked when real dataflow
1126 * When the pipeline is stalled, for example in PAUSED, this can
1127 * take an indeterminate amount of time.
1128 * You can pass NULL as the callback to make this call block. Be careful with
1129 * this blocking call as it might not return for reasons stated above.
1131 * Returns: TRUE if the pad could be blocked. This function can fail if the
1132 * wrong parameters were passed or the pad was already in the requested state.
1137 gst_pad_set_blocked_async (GstPad * pad, gboolean blocked,
1138 GstPadBlockCallback callback, gpointer user_data)
1140 return gst_pad_set_blocked_async_full (pad, blocked,
1141 callback, user_data, NULL);
1145 * gst_pad_set_blocked:
1146 * @pad: the #GstPad to block or unblock
1147 * @blocked: boolean indicating we should block or unblock
1149 * Blocks or unblocks the dataflow on a pad. This function is
1150 * a shortcut for gst_pad_set_blocked_async() with a NULL
1153 * Returns: TRUE if the pad could be blocked. This function can fail if the
1154 * wrong parameters were passed or the pad was already in the requested state.
1159 gst_pad_set_blocked (GstPad * pad, gboolean blocked)
1161 return gst_pad_set_blocked_async (pad, blocked, NULL, NULL);
1165 * gst_pad_is_blocked:
1166 * @pad: the #GstPad to query
1168 * Checks if the pad is blocked or not. This function returns the
1169 * last requested state of the pad. It is not certain that the pad
1170 * is actually blocking at this point (see gst_pad_is_blocking()).
1172 * Returns: TRUE if the pad is blocked.
1177 gst_pad_is_blocked (GstPad * pad)
1179 gboolean result = FALSE;
1181 g_return_val_if_fail (GST_IS_PAD (pad), result);
1183 GST_OBJECT_LOCK (pad);
1184 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED);
1185 GST_OBJECT_UNLOCK (pad);
1191 * gst_pad_is_blocking:
1192 * @pad: the #GstPad to query
1194 * Checks if the pad is blocking or not. This is a guaranteed state
1195 * of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
1197 * Returns: TRUE if the pad is blocking.
1204 gst_pad_is_blocking (GstPad * pad)
1206 gboolean result = FALSE;
1208 g_return_val_if_fail (GST_IS_PAD (pad), result);
1210 GST_OBJECT_LOCK (pad);
1211 /* the blocking flag is only valid if the pad is not flushing */
1212 result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKING) &&
1213 !GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLUSHING);
1214 GST_OBJECT_UNLOCK (pad);
1220 * gst_pad_set_activate_function:
1222 * @activate: the #GstPadActivateFunction to set.
1224 * Sets the given activate function for @pad. The activate function will
1225 * dispatch to gst_pad_activate_push() or gst_pad_activate_pull() to perform
1226 * the actual activation. Only makes sense to set on sink pads.
1228 * Call this function if your sink pad can start a pull-based task.
1231 gst_pad_set_activate_function (GstPad * pad, GstPadActivateFunction activate)
1233 g_return_if_fail (GST_IS_PAD (pad));
1235 GST_PAD_ACTIVATEFUNC (pad) = activate;
1236 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
1237 GST_DEBUG_FUNCPTR_NAME (activate));
1241 * gst_pad_set_activatepull_function:
1243 * @activatepull: the #GstPadActivateModeFunction to set.
1245 * Sets the given activate_pull function for the pad. An activate_pull function
1246 * prepares the element and any upstream connections for pulling. See XXX
1247 * part-activation.txt for details.
1250 gst_pad_set_activatepull_function (GstPad * pad,
1251 GstPadActivateModeFunction activatepull)
1253 g_return_if_fail (GST_IS_PAD (pad));
1255 GST_PAD_ACTIVATEPULLFUNC (pad) = activatepull;
1256 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepullfunc set to %s",
1257 GST_DEBUG_FUNCPTR_NAME (activatepull));
1261 * gst_pad_set_activatepush_function:
1263 * @activatepush: the #GstPadActivateModeFunction to set.
1265 * Sets the given activate_push function for the pad. An activate_push function
1266 * prepares the element for pushing. See XXX part-activation.txt for details.
1269 gst_pad_set_activatepush_function (GstPad * pad,
1270 GstPadActivateModeFunction activatepush)
1272 g_return_if_fail (GST_IS_PAD (pad));
1274 GST_PAD_ACTIVATEPUSHFUNC (pad) = activatepush;
1275 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatepushfunc set to %s",
1276 GST_DEBUG_FUNCPTR_NAME (activatepush));
1280 * gst_pad_set_chain_function:
1281 * @pad: a sink #GstPad.
1282 * @chain: the #GstPadChainFunction to set.
1284 * Sets the given chain function for the pad. The chain function is called to
1285 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1288 gst_pad_set_chain_function (GstPad * pad, GstPadChainFunction chain)
1290 g_return_if_fail (GST_IS_PAD (pad));
1291 g_return_if_fail (GST_PAD_IS_SINK (pad));
1293 GST_PAD_CHAINFUNC (pad) = chain;
1294 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
1295 GST_DEBUG_FUNCPTR_NAME (chain));
1299 * gst_pad_set_chain_list_function:
1300 * @pad: a sink #GstPad.
1301 * @chainlist: the #GstPadChainListFunction to set.
1303 * Sets the given chain list function for the pad. The chainlist function is
1304 * called to process a #GstBufferList input buffer list. See
1305 * #GstPadChainListFunction for more details.
1310 gst_pad_set_chain_list_function (GstPad * pad,
1311 GstPadChainListFunction chainlist)
1313 g_return_if_fail (GST_IS_PAD (pad));
1314 g_return_if_fail (GST_PAD_IS_SINK (pad));
1316 GST_PAD_CHAINLISTFUNC (pad) = chainlist;
1317 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainlistfunc set to %s",
1318 GST_DEBUG_FUNCPTR_NAME (chainlist));
1322 * gst_pad_set_getrange_function:
1323 * @pad: a source #GstPad.
1324 * @get: the #GstPadGetRangeFunction to set.
1326 * Sets the given getrange function for the pad. The getrange function is
1327 * called to produce a new #GstBuffer to start the processing pipeline. see
1328 * #GstPadGetRangeFunction for a description of the getrange function.
1331 gst_pad_set_getrange_function (GstPad * pad, GstPadGetRangeFunction get)
1333 g_return_if_fail (GST_IS_PAD (pad));
1334 g_return_if_fail (GST_PAD_IS_SRC (pad));
1336 GST_PAD_GETRANGEFUNC (pad) = get;
1338 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
1339 GST_DEBUG_FUNCPTR_NAME (get));
1343 * gst_pad_set_checkgetrange_function:
1344 * @pad: a source #GstPad.
1345 * @check: the #GstPadCheckGetRangeFunction to set.
1347 * Sets the given checkgetrange function for the pad. Implement this function
1348 * on a pad if you dynamically support getrange based scheduling on the pad.
1351 gst_pad_set_checkgetrange_function (GstPad * pad,
1352 GstPadCheckGetRangeFunction check)
1354 g_return_if_fail (GST_IS_PAD (pad));
1355 g_return_if_fail (GST_PAD_IS_SRC (pad));
1357 GST_PAD_CHECKGETRANGEFUNC (pad) = check;
1359 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "checkgetrangefunc set to %s",
1360 GST_DEBUG_FUNCPTR_NAME (check));
1364 * gst_pad_set_event_function:
1365 * @pad: a #GstPad of either direction.
1366 * @event: the #GstPadEventFunction to set.
1368 * Sets the given event handler for the pad.
1371 gst_pad_set_event_function (GstPad * pad, GstPadEventFunction event)
1373 g_return_if_fail (GST_IS_PAD (pad));
1375 GST_PAD_EVENTFUNC (pad) = event;
1377 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
1378 GST_DEBUG_FUNCPTR_NAME (event));
1382 * gst_pad_set_query_function:
1383 * @pad: a #GstPad of either direction.
1384 * @query: the #GstPadQueryFunction to set.
1386 * Set the given query function for the pad.
1389 gst_pad_set_query_function (GstPad * pad, GstPadQueryFunction query)
1391 g_return_if_fail (GST_IS_PAD (pad));
1393 GST_PAD_QUERYFUNC (pad) = query;
1395 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
1396 GST_DEBUG_FUNCPTR_NAME (query));
1400 * gst_pad_set_query_type_function:
1401 * @pad: a #GstPad of either direction.
1402 * @type_func: the #GstPadQueryTypeFunction to set.
1404 * Set the given query type function for the pad.
1407 gst_pad_set_query_type_function (GstPad * pad,
1408 GstPadQueryTypeFunction type_func)
1410 g_return_if_fail (GST_IS_PAD (pad));
1412 GST_PAD_QUERYTYPEFUNC (pad) = type_func;
1414 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "querytypefunc set to %s",
1415 GST_DEBUG_FUNCPTR_NAME (type_func));
1419 * gst_pad_get_query_types:
1422 * Get an array of supported queries that can be performed
1425 * Returns: a zero-terminated array of #GstQueryType.
1427 const GstQueryType *
1428 gst_pad_get_query_types (GstPad * pad)
1430 GstPadQueryTypeFunction func;
1432 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1434 if (G_UNLIKELY ((func = GST_PAD_QUERYTYPEFUNC (pad)) == NULL))
1446 gst_pad_get_query_types_dispatcher (GstPad * pad, const GstQueryType ** data)
1448 *data = gst_pad_get_query_types (pad);
1454 * gst_pad_get_query_types_default:
1457 * Invoke the default dispatcher for the query types on
1460 * Returns: an zero-terminated array of #GstQueryType, or NULL if none of the
1461 * internally-linked pads has a query types function.
1463 const GstQueryType *
1464 gst_pad_get_query_types_default (GstPad * pad)
1466 GstQueryType *result = NULL;
1468 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
1470 gst_pad_dispatcher (pad, (GstPadDispatcherFunction)
1471 gst_pad_get_query_types_dispatcher, &result);
1477 * gst_pad_set_iterate_internal_links_function:
1478 * @pad: a #GstPad of either direction.
1479 * @iterintlink: the #GstPadIterIntLinkFunction to set.
1481 * Sets the given internal link iterator function for the pad.
1486 gst_pad_set_iterate_internal_links_function (GstPad * pad,
1487 GstPadIterIntLinkFunction iterintlink)
1489 g_return_if_fail (GST_IS_PAD (pad));
1491 GST_PAD_ITERINTLINKFUNC (pad) = iterintlink;
1492 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link iterator set to %s",
1493 GST_DEBUG_FUNCPTR_NAME (iterintlink));
1497 * gst_pad_set_internal_link_function:
1498 * @pad: a #GstPad of either direction.
1499 * @intlink: the #GstPadIntLinkFunction to set.
1501 * Sets the given internal link function for the pad.
1503 * Deprecated: Use the thread-safe gst_pad_set_iterate_internal_links_function()
1505 #ifndef GST_REMOVE_DEPRECATED
1506 #ifdef GST_DISABLE_DEPRECATED
1508 gst_pad_set_internal_link_function (GstPad * pad,
1509 GstPadIntLinkFunction intlink);
1512 gst_pad_set_internal_link_function (GstPad * pad, GstPadIntLinkFunction intlink)
1514 g_return_if_fail (GST_IS_PAD (pad));
1516 GST_PAD_INTLINKFUNC (pad) = intlink;
1517 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link set to %s",
1518 GST_DEBUG_FUNCPTR_NAME (intlink));
1520 #endif /* GST_REMOVE_DEPRECATED */
1523 * gst_pad_set_link_function:
1525 * @link: the #GstPadLinkFunction to set.
1527 * Sets the given link function for the pad. It will be called when
1528 * the pad is linked with another pad.
1530 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1533 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1534 * cannot be made for some reason.
1536 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1537 * of the peer sink pad, if present.
1540 gst_pad_set_link_function (GstPad * pad, GstPadLinkFunction link)
1542 g_return_if_fail (GST_IS_PAD (pad));
1544 GST_PAD_LINKFUNC (pad) = link;
1545 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
1546 GST_DEBUG_FUNCPTR_NAME (link));
1550 * gst_pad_set_unlink_function:
1552 * @unlink: the #GstPadUnlinkFunction to set.
1554 * Sets the given unlink function for the pad. It will be called
1555 * when the pad is unlinked.
1558 gst_pad_set_unlink_function (GstPad * pad, GstPadUnlinkFunction unlink)
1560 g_return_if_fail (GST_IS_PAD (pad));
1562 GST_PAD_UNLINKFUNC (pad) = unlink;
1563 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
1564 GST_DEBUG_FUNCPTR_NAME (unlink));
1568 * gst_pad_set_getcaps_function:
1570 * @getcaps: the #GstPadGetCapsFunction to set.
1572 * Sets the given getcaps function for the pad. @getcaps should return the
1573 * allowable caps for a pad in the context of the element's state, its link to
1574 * other elements, and the devices or files it has opened. These caps must be a
1575 * subset of the pad template caps. In the NULL state with no links, @getcaps
1576 * should ideally return the same caps as the pad template. In rare
1577 * circumstances, an object property can affect the caps returned by @getcaps,
1578 * but this is discouraged.
1580 * You do not need to call this function if @pad's allowed caps are always the
1581 * same as the pad template caps. This can only be true if the padtemplate
1582 * has fixed simple caps.
1584 * For most filters, the caps returned by @getcaps is directly affected by the
1585 * allowed caps on other pads. For demuxers and decoders, the caps returned by
1586 * the srcpad's getcaps function is directly related to the stream data. Again,
1587 * @getcaps should return the most specific caps it reasonably can, since this
1588 * helps with autoplugging.
1590 * Note that the return value from @getcaps is owned by the caller, so the
1591 * caller should unref the caps after usage.
1594 gst_pad_set_getcaps_function (GstPad * pad, GstPadGetCapsFunction getcaps)
1596 g_return_if_fail (GST_IS_PAD (pad));
1598 GST_PAD_GETCAPSFUNC (pad) = getcaps;
1599 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getcapsfunc set to %s",
1600 GST_DEBUG_FUNCPTR_NAME (getcaps));
1604 * gst_pad_set_acceptcaps_function:
1606 * @acceptcaps: the #GstPadAcceptCapsFunction to set.
1608 * Sets the given acceptcaps function for the pad. The acceptcaps function
1609 * will be called to check if the pad can accept the given caps. Setting the
1610 * acceptcaps function to NULL restores the default behaviour of allowing
1611 * any caps that matches the caps from gst_pad_get_caps().
1614 gst_pad_set_acceptcaps_function (GstPad * pad,
1615 GstPadAcceptCapsFunction acceptcaps)
1617 g_return_if_fail (GST_IS_PAD (pad));
1619 GST_PAD_ACCEPTCAPSFUNC (pad) = acceptcaps;
1620 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "acceptcapsfunc set to %s",
1621 GST_DEBUG_FUNCPTR_NAME (acceptcaps));
1625 * gst_pad_set_fixatecaps_function:
1627 * @fixatecaps: the #GstPadFixateCapsFunction to set.
1629 * Sets the given fixatecaps function for the pad. The fixatecaps function
1630 * will be called whenever the default values for a GstCaps needs to be
1634 gst_pad_set_fixatecaps_function (GstPad * pad,
1635 GstPadFixateCapsFunction fixatecaps)
1637 g_return_if_fail (GST_IS_PAD (pad));
1639 GST_PAD_FIXATECAPSFUNC (pad) = fixatecaps;
1640 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fixatecapsfunc set to %s",
1641 GST_DEBUG_FUNCPTR_NAME (fixatecaps));
1645 * gst_pad_set_setcaps_function:
1647 * @setcaps: the #GstPadSetCapsFunction to set.
1649 * Sets the given setcaps function for the pad. The setcaps function
1650 * will be called whenever a buffer with a new media type is pushed or
1651 * pulled from the pad. The pad/element needs to update its internal
1652 * structures to process the new media type. If this new type is not
1653 * acceptable, the setcaps function should return FALSE.
1656 gst_pad_set_setcaps_function (GstPad * pad, GstPadSetCapsFunction setcaps)
1658 g_return_if_fail (GST_IS_PAD (pad));
1660 GST_PAD_SETCAPSFUNC (pad) = setcaps;
1661 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "setcapsfunc set to %s",
1662 GST_DEBUG_FUNCPTR_NAME (setcaps));
1666 * gst_pad_set_bufferalloc_function:
1667 * @pad: a sink #GstPad.
1668 * @bufalloc: the #GstPadBufferAllocFunction to set.
1670 * Sets the given bufferalloc function for the pad. Note that the
1671 * bufferalloc function can only be set on sinkpads.
1674 gst_pad_set_bufferalloc_function (GstPad * pad,
1675 GstPadBufferAllocFunction bufalloc)
1677 g_return_if_fail (GST_IS_PAD (pad));
1678 g_return_if_fail (GST_PAD_IS_SINK (pad));
1680 GST_PAD_BUFFERALLOCFUNC (pad) = bufalloc;
1681 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "bufferallocfunc set to %s",
1682 GST_DEBUG_FUNCPTR_NAME (bufalloc));
1687 * @srcpad: the source #GstPad to unlink.
1688 * @sinkpad: the sink #GstPad to unlink.
1690 * Unlinks the source pad from the sink pad. Will emit the #GstPad::unlinked
1691 * signal on both pads.
1693 * Returns: TRUE if the pads were unlinked. This function returns FALSE if
1694 * the pads were not linked together.
1699 gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
1701 gboolean result = FALSE;
1702 GstElement *parent = NULL;
1704 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
1705 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), FALSE);
1706 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
1707 g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad), FALSE);
1709 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
1710 GST_DEBUG_PAD_NAME (srcpad), srcpad,
1711 GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
1713 /* We need to notify the parent before taking any pad locks as the bin in
1714 * question might be waiting for a lock on the pad while holding its lock
1715 * that our message will try to take. */
1716 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
1717 if (GST_IS_ELEMENT (parent)) {
1718 gst_element_post_message (parent,
1719 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
1720 GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, TRUE));
1722 gst_object_unref (parent);
1727 GST_OBJECT_LOCK (srcpad);
1729 GST_OBJECT_LOCK (sinkpad);
1731 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
1732 goto not_linked_together;
1734 if (GST_PAD_UNLINKFUNC (srcpad)) {
1735 GST_PAD_UNLINKFUNC (srcpad) (srcpad);
1737 if (GST_PAD_UNLINKFUNC (sinkpad)) {
1738 GST_PAD_UNLINKFUNC (sinkpad) (sinkpad);
1741 pad_invalidate_cache (srcpad);
1743 /* first clear peers */
1744 GST_PAD_PEER (srcpad) = NULL;
1745 GST_PAD_PEER (sinkpad) = NULL;
1747 GST_OBJECT_UNLOCK (sinkpad);
1748 GST_OBJECT_UNLOCK (srcpad);
1750 /* fire off a signal to each of the pads telling them
1751 * that they've been unlinked */
1752 g_signal_emit (srcpad, gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
1753 g_signal_emit (sinkpad, gst_pad_signals[PAD_UNLINKED], 0, srcpad);
1755 GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
1756 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1761 if (parent != NULL) {
1762 gst_element_post_message (parent,
1763 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
1764 GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, FALSE));
1765 gst_object_unref (parent);
1770 not_linked_together:
1772 /* we do not emit a warning in this case because unlinking cannot
1773 * be made MT safe.*/
1774 GST_OBJECT_UNLOCK (sinkpad);
1775 GST_OBJECT_UNLOCK (srcpad);
1781 * gst_pad_is_linked:
1782 * @pad: pad to check
1784 * Checks if a @pad is linked to another pad or not.
1786 * Returns: TRUE if the pad is linked, FALSE otherwise.
1791 gst_pad_is_linked (GstPad * pad)
1795 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
1797 GST_OBJECT_LOCK (pad);
1798 result = (GST_PAD_PEER (pad) != NULL);
1799 GST_OBJECT_UNLOCK (pad);
1804 /* get the caps from both pads and see if the intersection
1807 * This function should be called with the pad LOCK on both
1811 gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink,
1812 GstPadLinkCheck flags)
1814 GstCaps *srccaps = NULL;
1815 GstCaps *sinkcaps = NULL;
1816 gboolean compatible = FALSE;
1818 if (!(flags & (GST_PAD_LINK_CHECK_CAPS | GST_PAD_LINK_CHECK_TEMPLATE_CAPS)))
1821 /* Doing the expensive caps checking takes priority over only checking the template caps */
1822 if (flags & GST_PAD_LINK_CHECK_CAPS) {
1823 srccaps = gst_pad_get_caps_unlocked (src);
1824 sinkcaps = gst_pad_get_caps_unlocked (sink);
1826 /* If one of the two pads doesn't have a template, consider the intersection
1828 if (G_UNLIKELY ((GST_PAD_PAD_TEMPLATE (src) == NULL)
1829 || (GST_PAD_PAD_TEMPLATE (sink) == NULL))) {
1833 srccaps = gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (src)));
1835 gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (sink)));
1838 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, src, "src caps %" GST_PTR_FORMAT,
1840 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, sink, "sink caps %" GST_PTR_FORMAT,
1843 /* if we have caps on both pads we can check the intersection. If one
1844 * of the caps is NULL, we return TRUE. */
1845 if (G_UNLIKELY (srccaps == NULL || sinkcaps == NULL)) {
1847 gst_caps_unref (srccaps);
1849 gst_caps_unref (sinkcaps);
1853 compatible = gst_caps_can_intersect (srccaps, sinkcaps);
1854 gst_caps_unref (srccaps);
1855 gst_caps_unref (sinkcaps);
1858 GST_CAT_DEBUG (GST_CAT_CAPS, "caps are %scompatible",
1859 (compatible ? "" : "not"));
1864 /* check if the grandparents of both pads are the same.
1865 * This check is required so that we don't try to link
1866 * pads from elements in different bins without ghostpads.
1868 * The LOCK should be held on both pads
1871 gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
1873 GstObject *psrc, *psink;
1875 psrc = GST_OBJECT_PARENT (src);
1876 psink = GST_OBJECT_PARENT (sink);
1878 /* if one of the pads has no parent, we allow the link */
1879 if (G_UNLIKELY (psrc == NULL || psink == NULL))
1882 /* only care about parents that are elements */
1883 if (G_UNLIKELY (!GST_IS_ELEMENT (psrc) || !GST_IS_ELEMENT (psink)))
1884 goto no_element_parent;
1886 /* if the parents are the same, we have a loop */
1887 if (G_UNLIKELY (psrc == psink))
1890 /* if they both have a parent, we check the grandparents. We can not lock
1891 * the parent because we hold on the child (pad) and the locking order is
1892 * parent >> child. */
1893 psrc = GST_OBJECT_PARENT (psrc);
1894 psink = GST_OBJECT_PARENT (psink);
1896 /* if they have grandparents but they are not the same */
1897 if (G_UNLIKELY (psrc != psink))
1898 goto wrong_grandparents;
1905 GST_CAT_DEBUG (GST_CAT_CAPS,
1906 "one of the pads has no parent %" GST_PTR_FORMAT " and %"
1907 GST_PTR_FORMAT, psrc, psink);
1912 GST_CAT_DEBUG (GST_CAT_CAPS,
1913 "one of the pads has no element parent %" GST_PTR_FORMAT " and %"
1914 GST_PTR_FORMAT, psrc, psink);
1919 GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
1925 GST_CAT_DEBUG (GST_CAT_CAPS,
1926 "pads have different grandparents %" GST_PTR_FORMAT " and %"
1927 GST_PTR_FORMAT, psrc, psink);
1932 /* FIXME leftover from an attempt at refactoring... */
1933 /* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
1934 * the two pads will be locked in the srcpad, sinkpad order. */
1935 static GstPadLinkReturn
1936 gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad, GstPadLinkCheck flags)
1938 GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
1939 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
1941 GST_OBJECT_LOCK (srcpad);
1943 if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
1944 goto src_was_linked;
1946 GST_OBJECT_LOCK (sinkpad);
1948 if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
1949 goto sink_was_linked;
1951 /* check hierarchy, pads can only be linked if the grandparents
1953 if ((flags & GST_PAD_LINK_CHECK_HIERARCHY)
1954 && !gst_pad_link_check_hierarchy (srcpad, sinkpad))
1955 goto wrong_hierarchy;
1957 /* check pad caps for non-empty intersection */
1958 if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad, flags))
1961 /* FIXME check pad scheduling for non-empty intersection */
1963 return GST_PAD_LINK_OK;
1967 GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
1968 GST_DEBUG_PAD_NAME (srcpad),
1969 GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
1970 /* we do not emit a warning in this case because unlinking cannot
1971 * be made MT safe.*/
1972 GST_OBJECT_UNLOCK (srcpad);
1973 return GST_PAD_LINK_WAS_LINKED;
1977 GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
1978 GST_DEBUG_PAD_NAME (sinkpad),
1979 GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
1980 /* we do not emit a warning in this case because unlinking cannot
1981 * be made MT safe.*/
1982 GST_OBJECT_UNLOCK (sinkpad);
1983 GST_OBJECT_UNLOCK (srcpad);
1984 return GST_PAD_LINK_WAS_LINKED;
1988 GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
1989 GST_OBJECT_UNLOCK (sinkpad);
1990 GST_OBJECT_UNLOCK (srcpad);
1991 return GST_PAD_LINK_WRONG_HIERARCHY;
1995 GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
1996 GST_OBJECT_UNLOCK (sinkpad);
1997 GST_OBJECT_UNLOCK (srcpad);
1998 return GST_PAD_LINK_NOFORMAT;
2004 * @srcpad: the source #GstPad.
2005 * @sinkpad: the sink #GstPad.
2007 * Checks if the source pad and the sink pad are compatible so they can be
2010 * Returns: TRUE if the pads can be linked.
2013 gst_pad_can_link (GstPad * srcpad, GstPad * sinkpad)
2015 GstPadLinkReturn result;
2017 /* generic checks */
2018 g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
2019 g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
2021 GST_CAT_INFO (GST_CAT_PADS, "check if %s:%s can link with %s:%s",
2022 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2024 /* gst_pad_link_prepare does everything for us, we only release the locks
2025 * on the pads that it gets us. If this function returns !OK the locks are not
2027 result = gst_pad_link_prepare (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
2028 if (result != GST_PAD_LINK_OK)
2031 GST_OBJECT_UNLOCK (srcpad);
2032 GST_OBJECT_UNLOCK (sinkpad);
2035 return result == GST_PAD_LINK_OK;
2039 * gst_pad_link_full:
2040 * @srcpad: the source #GstPad to link.
2041 * @sinkpad: the sink #GstPad to link.
2042 * @flags: the checks to validate when linking
2044 * Links the source pad and the sink pad.
2046 * This variant of #gst_pad_link provides a more granular control on the
2047 * checks being done when linking. While providing some considerable speedups
2048 * the caller of this method must be aware that wrong usage of those flags
2049 * can cause severe issues. Refer to the documentation of #GstPadLinkCheck
2050 * for more information.
2054 * Returns: A result code indicating if the connection worked or
2060 gst_pad_link_full (GstPad * srcpad, GstPad * sinkpad, GstPadLinkCheck flags)
2062 GstPadLinkReturn result;
2065 g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
2066 g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), GST_PAD_LINK_WRONG_DIRECTION);
2067 g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
2068 g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad),
2069 GST_PAD_LINK_WRONG_DIRECTION);
2071 /* Notify the parent early. See gst_pad_unlink for details. */
2072 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
2073 if (GST_IS_ELEMENT (parent)) {
2074 gst_element_post_message (parent,
2075 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
2076 GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, TRUE));
2078 gst_object_unref (parent);
2083 /* prepare will also lock the two pads */
2084 result = gst_pad_link_prepare (srcpad, sinkpad, flags);
2086 if (result != GST_PAD_LINK_OK)
2089 /* must set peers before calling the link function */
2090 GST_PAD_PEER (srcpad) = sinkpad;
2091 GST_PAD_PEER (sinkpad) = srcpad;
2093 GST_OBJECT_UNLOCK (sinkpad);
2094 GST_OBJECT_UNLOCK (srcpad);
2096 /* FIXME released the locks here, concurrent thread might link
2097 * something else. */
2098 if (GST_PAD_LINKFUNC (srcpad)) {
2099 /* this one will call the peer link function */
2100 result = GST_PAD_LINKFUNC (srcpad) (srcpad, sinkpad);
2101 } else if (GST_PAD_LINKFUNC (sinkpad)) {
2102 /* if no source link function, we need to call the sink link
2103 * function ourselves. */
2104 result = GST_PAD_LINKFUNC (sinkpad) (sinkpad, srcpad);
2106 result = GST_PAD_LINK_OK;
2109 GST_OBJECT_LOCK (srcpad);
2110 GST_OBJECT_LOCK (sinkpad);
2112 if (result == GST_PAD_LINK_OK) {
2113 GST_OBJECT_UNLOCK (sinkpad);
2114 GST_OBJECT_UNLOCK (srcpad);
2116 /* fire off a signal to each of the pads telling them
2117 * that they've been linked */
2118 g_signal_emit (srcpad, gst_pad_signals[PAD_LINKED], 0, sinkpad);
2119 g_signal_emit (sinkpad, gst_pad_signals[PAD_LINKED], 0, srcpad);
2121 GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
2122 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2124 GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed",
2125 GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
2127 GST_PAD_PEER (srcpad) = NULL;
2128 GST_PAD_PEER (sinkpad) = NULL;
2130 GST_OBJECT_UNLOCK (sinkpad);
2131 GST_OBJECT_UNLOCK (srcpad);
2136 gst_element_post_message (parent,
2137 gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
2138 GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, FALSE));
2139 gst_object_unref (parent);
2147 * @srcpad: the source #GstPad to link.
2148 * @sinkpad: the sink #GstPad to link.
2150 * Links the source pad and the sink pad.
2152 * Returns: A result code indicating if the connection worked or
2158 gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
2160 return gst_pad_link_full (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
2164 gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
2166 GstPadTemplate **template_p;
2168 /* this function would need checks if it weren't static */
2170 GST_OBJECT_LOCK (pad);
2171 template_p = &pad->padtemplate;
2172 gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
2173 GST_OBJECT_UNLOCK (pad);
2176 gst_pad_template_pad_created (templ, pad);
2180 * gst_pad_get_pad_template:
2183 * Gets the template for @pad.
2185 * Returns: the #GstPadTemplate from which this pad was instantiated, or %NULL
2186 * if this pad has no template.
2188 * FIXME: currently returns an unrefcounted padtemplate.
2191 gst_pad_get_pad_template (GstPad * pad)
2193 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2195 return GST_PAD_PAD_TEMPLATE (pad);
2199 /* should be called with the pad LOCK held */
2200 /* refs the caps, so caller is responsible for getting it unreffed */
2202 gst_pad_get_caps_unlocked (GstPad * pad)
2204 GstCaps *result = NULL;
2205 GstPadTemplate *templ;
2207 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
2209 if (GST_PAD_GETCAPSFUNC (pad)) {
2210 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2211 "dispatching to pad getcaps function");
2213 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_GETCAPS);
2214 GST_OBJECT_UNLOCK (pad);
2215 result = GST_PAD_GETCAPSFUNC (pad) (pad);
2216 GST_OBJECT_LOCK (pad);
2217 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_GETCAPS);
2219 if (result == NULL) {
2220 g_critical ("pad %s:%s returned NULL caps from getcaps function",
2221 GST_DEBUG_PAD_NAME (pad));
2223 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2224 "pad getcaps returned %" GST_PTR_FORMAT, result);
2225 #ifndef G_DISABLE_ASSERT
2226 /* check that the returned caps are a real subset of the template caps */
2227 if (GST_PAD_PAD_TEMPLATE (pad)) {
2228 const GstCaps *templ_caps =
2229 GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2230 if (!gst_caps_is_subset (result, templ_caps)) {
2233 GST_CAT_ERROR_OBJECT (GST_CAT_CAPS, pad,
2234 "pad returned caps %" GST_PTR_FORMAT
2235 " which are not a real subset of its template caps %"
2236 GST_PTR_FORMAT, result, templ_caps);
2238 ("pad %s:%s returned caps which are not a real "
2239 "subset of its template caps", GST_DEBUG_PAD_NAME (pad));
2240 temp = gst_caps_intersect (templ_caps, result);
2241 gst_caps_unref (result);
2249 if ((templ = GST_PAD_PAD_TEMPLATE (pad))) {
2250 result = GST_PAD_TEMPLATE_CAPS (templ);
2251 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2252 "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, result,
2255 result = gst_caps_ref (result);
2258 if ((result = GST_PAD_CAPS (pad))) {
2259 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2260 "using pad caps %p %" GST_PTR_FORMAT, result, result);
2262 result = gst_caps_ref (result);
2266 /* this almost never happens */
2267 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
2268 result = gst_caps_new_empty ();
2274 /* FIXME-0.11: what about making this the default and using
2275 * gst_caps_make_writable() explicitely where needed
2278 * gst_pad_get_caps_reffed:
2279 * @pad: a #GstPad to get the capabilities of.
2281 * Gets the capabilities this pad can produce or consume. Preferred function if
2282 * one only wants to read or intersect the caps.
2284 * Returns: the caps of the pad with incremented ref-count.
2289 gst_pad_get_caps_reffed (GstPad * pad)
2291 GstCaps *result = NULL;
2293 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2295 GST_OBJECT_LOCK (pad);
2297 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get pad caps");
2299 result = gst_pad_get_caps_unlocked (pad);
2301 GST_OBJECT_UNLOCK (pad);
2308 * @pad: a #GstPad to get the capabilities of.
2310 * Gets the capabilities this pad can produce or consume.
2311 * Note that this method doesn't necessarily return the caps set by
2312 * gst_pad_set_caps() - use GST_PAD_CAPS() for that instead.
2313 * gst_pad_get_caps returns all possible caps a pad can operate with, using
2314 * the pad's get_caps function;
2315 * this returns the pad template caps if not explicitly set.
2317 * Returns: a newly allocated copy of the #GstCaps of this pad.
2322 gst_pad_get_caps (GstPad * pad)
2324 GstCaps *result = gst_pad_get_caps_reffed (pad);
2326 /* be sure that we have a copy */
2327 if (G_LIKELY (result))
2328 result = gst_caps_make_writable (result);
2333 /* FIXME-0.11: what about making this the default and using
2334 * gst_caps_make_writable() explicitely where needed
2337 * gst_pad_peer_get_caps_reffed:
2338 * @pad: a #GstPad to get the capabilities of.
2340 * Gets the capabilities of the peer connected to this pad. Preferred function
2341 * if one only wants to read or intersect the caps.
2343 * Returns: the caps of the pad with incremented ref-count.
2348 gst_pad_peer_get_caps_reffed (GstPad * pad)
2351 GstCaps *result = NULL;
2353 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2355 GST_OBJECT_LOCK (pad);
2357 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2359 peerpad = GST_PAD_PEER (pad);
2360 if (G_UNLIKELY (peerpad == NULL))
2363 gst_object_ref (peerpad);
2364 GST_OBJECT_UNLOCK (pad);
2366 result = gst_pad_get_caps_reffed (peerpad);
2368 gst_object_unref (peerpad);
2374 GST_OBJECT_UNLOCK (pad);
2380 * gst_pad_peer_get_caps:
2381 * @pad: a #GstPad to get the peer capabilities of.
2383 * Gets the capabilities of the peer connected to this pad. Similar to
2384 * gst_pad_get_caps().
2386 * Returns: a newly allocated copy of the #GstCaps of the peer pad. Use
2387 * gst_caps_unref() to get rid of it. This function returns %NULL if there is
2391 gst_pad_peer_get_caps (GstPad * pad)
2394 GstCaps *result = NULL;
2396 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2398 GST_OBJECT_LOCK (pad);
2400 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "get peer caps");
2402 peerpad = GST_PAD_PEER (pad);
2403 if (G_UNLIKELY (peerpad == NULL))
2406 gst_object_ref (peerpad);
2407 GST_OBJECT_UNLOCK (pad);
2409 result = gst_pad_get_caps (peerpad);
2411 gst_object_unref (peerpad);
2417 GST_OBJECT_UNLOCK (pad);
2423 fixate_value (GValue * dest, const GValue * src)
2425 if (G_VALUE_TYPE (src) == GST_TYPE_INT_RANGE) {
2426 g_value_init (dest, G_TYPE_INT);
2427 g_value_set_int (dest, gst_value_get_int_range_min (src));
2428 } else if (G_VALUE_TYPE (src) == GST_TYPE_DOUBLE_RANGE) {
2429 g_value_init (dest, G_TYPE_DOUBLE);
2430 g_value_set_double (dest, gst_value_get_double_range_min (src));
2431 } else if (G_VALUE_TYPE (src) == GST_TYPE_FRACTION_RANGE) {
2432 gst_value_init_and_copy (dest, gst_value_get_fraction_range_min (src));
2433 } else if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
2434 GValue temp = { 0 };
2436 /* list could be empty */
2437 if (gst_value_list_get_size (src) <= 0)
2440 gst_value_init_and_copy (&temp, gst_value_list_get_value (src, 0));
2442 if (!fixate_value (dest, &temp))
2443 gst_value_init_and_copy (dest, &temp);
2444 g_value_unset (&temp);
2445 } else if (G_VALUE_TYPE (src) == GST_TYPE_ARRAY) {
2446 gboolean res = FALSE;
2449 len = gst_value_array_get_size (src);
2450 g_value_init (dest, GST_TYPE_ARRAY);
2451 for (n = 0; n < len; n++) {
2453 const GValue *orig_kid = gst_value_array_get_value (src, n);
2455 if (!fixate_value (&kid, orig_kid))
2456 gst_value_init_and_copy (&kid, orig_kid);
2459 gst_value_array_append_value (dest, &kid);
2460 g_value_unset (&kid);
2464 g_value_unset (dest);
2475 gst_pad_default_fixate (GQuark field_id, const GValue * value, gpointer data)
2477 GstStructure *s = data;
2480 if (fixate_value (&v, value)) {
2481 gst_structure_id_set_value (s, field_id, &v);
2489 * gst_pad_fixate_caps:
2490 * @pad: a #GstPad to fixate
2491 * @caps: the #GstCaps to fixate
2493 * Fixate a caps on the given pad. Modifies the caps in place, so you should
2494 * make sure that the caps are actually writable (see gst_caps_make_writable()).
2497 gst_pad_fixate_caps (GstPad * pad, GstCaps * caps)
2499 GstPadFixateCapsFunction fixatefunc;
2502 g_return_if_fail (GST_IS_PAD (pad));
2503 g_return_if_fail (caps != NULL);
2504 g_return_if_fail (!gst_caps_is_empty (caps));
2505 /* FIXME-0.11: do not allow fixating any-caps
2506 * g_return_if_fail (!gst_caps_is_any (caps));
2509 if (gst_caps_is_fixed (caps) || gst_caps_is_any (caps))
2512 fixatefunc = GST_PAD_FIXATECAPSFUNC (pad);
2514 fixatefunc (pad, caps);
2517 /* default fixation */
2518 gst_caps_truncate (caps);
2519 s = gst_caps_get_structure (caps, 0);
2520 gst_structure_foreach (s, gst_pad_default_fixate, s);
2523 /* Default accept caps implementation just checks against
2524 * against the allowed caps for the pad */
2526 gst_pad_acceptcaps_default (GstPad * pad, GstCaps * caps)
2528 /* get the caps and see if it intersects to something not empty */
2530 gboolean result = FALSE;
2532 GST_DEBUG_OBJECT (pad, "caps %" GST_PTR_FORMAT, caps);
2534 allowed = gst_pad_get_caps_reffed (pad);
2536 goto nothing_allowed;
2538 GST_DEBUG_OBJECT (pad, "allowed caps %" GST_PTR_FORMAT, allowed);
2540 result = gst_caps_can_intersect (allowed, caps);
2542 gst_caps_unref (allowed);
2549 GST_DEBUG_OBJECT (pad, "no caps allowed on the pad");
2555 * gst_pad_accept_caps:
2556 * @pad: a #GstPad to check
2557 * @caps: a #GstCaps to check on the pad
2559 * Check if the given pad accepts the caps.
2561 * Returns: TRUE if the pad can accept the caps.
2564 gst_pad_accept_caps (GstPad * pad, GstCaps * caps)
2567 GstPadAcceptCapsFunction acceptfunc;
2568 GstCaps *existing = NULL;
2570 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2572 /* any pad can be unnegotiated */
2576 /* lock for checking the existing caps */
2577 GST_OBJECT_LOCK (pad);
2578 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "accept caps of %p", caps);
2579 /* The current caps on a pad are trivially acceptable */
2580 if (G_LIKELY ((existing = GST_PAD_CAPS (pad)))) {
2581 if (caps == existing || gst_caps_is_equal (caps, existing))
2584 acceptfunc = GST_PAD_ACCEPTCAPSFUNC (pad);
2585 GST_OBJECT_UNLOCK (pad);
2587 if (G_LIKELY (acceptfunc)) {
2588 /* we can call the function */
2589 result = acceptfunc (pad, caps);
2590 GST_DEBUG_OBJECT (pad, "acceptfunc returned %d", result);
2592 /* Only null if the element explicitly unset it */
2593 result = gst_pad_acceptcaps_default (pad, caps);
2594 GST_DEBUG_OBJECT (pad, "default acceptcaps returned %d", result);
2600 GST_DEBUG_OBJECT (pad, "pad had same caps");
2601 GST_OBJECT_UNLOCK (pad);
2607 * gst_pad_peer_accept_caps:
2608 * @pad: a #GstPad to check the peer of
2609 * @caps: a #GstCaps to check on the pad
2611 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
2614 * Returns: TRUE if the peer of @pad can accept the caps or @pad has no peer.
2617 gst_pad_peer_accept_caps (GstPad * pad, GstCaps * caps)
2622 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2624 GST_OBJECT_LOCK (pad);
2626 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "peer accept caps of (%p)", pad);
2628 peerpad = GST_PAD_PEER (pad);
2629 if (G_UNLIKELY (peerpad == NULL))
2632 gst_object_ref (peerpad);
2633 /* release lock before calling external methods but keep ref to pad */
2634 GST_OBJECT_UNLOCK (pad);
2636 result = gst_pad_accept_caps (peerpad, caps);
2638 gst_object_unref (peerpad);
2644 GST_OBJECT_UNLOCK (pad);
2651 * @pad: a #GstPad to set the capabilities of.
2652 * @caps: a #GstCaps to set.
2654 * Sets the capabilities of this pad. The caps must be fixed. Any previous
2655 * caps on the pad will be unreffed. This function refs the caps so you should
2656 * unref if as soon as you don't need it anymore.
2657 * It is possible to set NULL caps, which will make the pad unnegotiated
2660 * Returns: TRUE if the caps could be set. FALSE if the caps were not fixed
2661 * or bad parameters were provided to this function.
2666 gst_pad_set_caps (GstPad * pad, GstCaps * caps)
2668 GstPadSetCapsFunction setcaps;
2671 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
2672 g_return_val_if_fail (caps == NULL || gst_caps_is_fixed (caps), FALSE);
2674 GST_OBJECT_LOCK (pad);
2675 existing = GST_PAD_CAPS (pad);
2676 if (existing == caps)
2679 if (gst_caps_is_equal (caps, existing))
2680 goto setting_same_caps;
2682 setcaps = GST_PAD_SETCAPSFUNC (pad);
2684 /* call setcaps function to configure the pad only if the
2685 * caps is not NULL */
2686 if (setcaps != NULL && caps) {
2687 if (!GST_PAD_IS_IN_SETCAPS (pad)) {
2688 GST_OBJECT_FLAG_SET (pad, GST_PAD_IN_SETCAPS);
2689 GST_OBJECT_UNLOCK (pad);
2690 if (!setcaps (pad, caps))
2692 GST_OBJECT_LOCK (pad);
2693 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2695 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad was dispatching");
2699 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2700 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "caps %p %" GST_PTR_FORMAT, caps,
2702 GST_OBJECT_UNLOCK (pad);
2704 #if GLIB_CHECK_VERSION(2,26,0)
2705 g_object_notify_by_pspec ((GObject *) pad, pspec_caps);
2707 g_object_notify ((GObject *) pad, "caps");
2714 GST_OBJECT_UNLOCK (pad);
2719 gst_caps_replace (&GST_PAD_CAPS (pad), caps);
2720 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2721 "caps %p %" GST_PTR_FORMAT " same as existing, updating ptr only", caps,
2723 GST_OBJECT_UNLOCK (pad);
2730 GST_OBJECT_LOCK (pad);
2731 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_IN_SETCAPS);
2732 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2733 "caps %" GST_PTR_FORMAT " could not be set", caps);
2734 GST_OBJECT_UNLOCK (pad);
2741 gst_pad_configure_sink (GstPad * pad, GstCaps * caps)
2745 /* See if pad accepts the caps */
2746 if (!gst_caps_can_intersect (caps, gst_pad_get_pad_template_caps (pad)))
2749 /* set caps on pad if call succeeds */
2750 res = gst_pad_set_caps (pad, caps);
2751 /* no need to unref the caps here, set_caps takes a ref and
2752 * our ref goes away when we leave this function. */
2758 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2759 "caps %" GST_PTR_FORMAT " not accepted", caps);
2764 /* returns TRUE if the src pad could be configured to accept the given caps */
2766 gst_pad_configure_src (GstPad * pad, GstCaps * caps, gboolean dosetcaps)
2771 /* See if pad accepts the caps */
2772 if (!gst_pad_accept_caps (pad, caps))
2775 res = gst_pad_set_caps (pad, caps);
2783 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
2784 "caps %" GST_PTR_FORMAT " not accepted", caps);
2790 * gst_pad_get_pad_template_caps:
2791 * @pad: a #GstPad to get the template capabilities from.
2793 * Gets the capabilities for @pad's template.
2795 * Returns: the #GstCaps of this pad template. If you intend to keep a
2796 * reference on the caps, make a copy (see gst_caps_copy ()).
2799 gst_pad_get_pad_template_caps (GstPad * pad)
2801 static GstStaticCaps anycaps = GST_STATIC_CAPS ("ANY");
2803 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2805 if (GST_PAD_PAD_TEMPLATE (pad))
2806 return GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad));
2808 return gst_static_caps_get (&anycaps);
2813 * @pad: a #GstPad to get the peer of.
2815 * Gets the peer of @pad. This function refs the peer pad so
2816 * you need to unref it after use.
2818 * Returns: the peer #GstPad. Unref after usage.
2823 gst_pad_get_peer (GstPad * pad)
2827 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2829 GST_OBJECT_LOCK (pad);
2830 result = GST_PAD_PEER (pad);
2832 gst_object_ref (result);
2833 GST_OBJECT_UNLOCK (pad);
2839 * gst_pad_get_allowed_caps:
2842 * Gets the capabilities of the allowed media types that can flow through
2843 * @pad and its peer.
2845 * The allowed capabilities is calculated as the intersection of the results of
2846 * calling gst_pad_get_caps() on @pad and its peer. The caller owns a reference
2847 * on the resulting caps.
2849 * Returns: the allowed #GstCaps of the pad link. Unref the caps when you no
2850 * longer need it. This function returns NULL when @pad has no peer.
2855 gst_pad_get_allowed_caps (GstPad * pad)
2862 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2864 GST_OBJECT_LOCK (pad);
2866 peer = GST_PAD_PEER (pad);
2867 if (G_UNLIKELY (peer == NULL))
2870 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting allowed caps");
2872 gst_object_ref (peer);
2873 GST_OBJECT_UNLOCK (pad);
2874 mycaps = gst_pad_get_caps_reffed (pad);
2876 peercaps = gst_pad_get_caps_reffed (peer);
2877 gst_object_unref (peer);
2879 caps = gst_caps_intersect (mycaps, peercaps);
2880 gst_caps_unref (peercaps);
2881 gst_caps_unref (mycaps);
2883 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "allowed caps %" GST_PTR_FORMAT,
2890 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2891 GST_OBJECT_UNLOCK (pad);
2898 * gst_pad_get_negotiated_caps:
2901 * Gets the capabilities of the media type that currently flows through @pad
2904 * This function can be used on both src and sinkpads. Note that srcpads are
2905 * always negotiated before sinkpads so it is possible that the negotiated caps
2906 * on the srcpad do not match the negotiated caps of the peer.
2908 * Returns: the negotiated #GstCaps of the pad link. Unref the caps when
2909 * you no longer need it. This function returns NULL when the @pad has no
2910 * peer or is not negotiated yet.
2915 gst_pad_get_negotiated_caps (GstPad * pad)
2920 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
2922 GST_OBJECT_LOCK (pad);
2924 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
2927 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting negotiated caps");
2929 caps = GST_PAD_CAPS (pad);
2931 gst_caps_ref (caps);
2932 GST_OBJECT_UNLOCK (pad);
2934 GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "negotiated caps %" GST_PTR_FORMAT,
2941 GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
2942 GST_OBJECT_UNLOCK (pad);
2948 /* calls the buffer_alloc function on the given pad */
2949 static GstFlowReturn
2950 gst_pad_buffer_alloc_unchecked (GstPad * pad, guint64 offset, gint size,
2951 GstCaps * caps, GstBuffer ** buf)
2954 GstPadBufferAllocFunction bufferallocfunc;
2956 GST_OBJECT_LOCK (pad);
2957 /* when the pad is flushing we cannot give a buffer */
2958 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
2961 bufferallocfunc = pad->bufferallocfunc;
2963 if (offset == GST_BUFFER_OFFSET_NONE) {
2964 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2965 "calling bufferallocfunc &%s (@%p) for size %d offset NONE",
2966 GST_DEBUG_FUNCPTR_NAME (bufferallocfunc), bufferallocfunc, size);
2968 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
2969 "calling bufferallocfunc &%s (@%p) of for size %d offset %"
2970 G_GUINT64_FORMAT, GST_DEBUG_FUNCPTR_NAME (bufferallocfunc),
2971 bufferallocfunc, size, offset);
2973 GST_OBJECT_UNLOCK (pad);
2975 /* G_LIKELY for now since most elements don't implement a buffer alloc
2976 * function and there is no default alloc proxy function as this is usually
2978 if (G_LIKELY (bufferallocfunc == NULL))
2981 ret = bufferallocfunc (pad, offset, size, caps, buf);
2983 if (G_UNLIKELY (ret != GST_FLOW_OK))
2986 /* no error, but NULL buffer means fallback to the default */
2987 if (G_UNLIKELY (*buf == NULL))
2990 /* If the buffer alloc function didn't set up the caps like it should,
2992 if (G_UNLIKELY (caps && (GST_BUFFER_CAPS (*buf) == NULL))) {
2993 GST_WARNING_OBJECT (pad,
2994 "Buffer allocation function did not set caps. Setting");
2995 gst_buffer_set_caps (*buf, caps);
3001 /* pad was flushing */
3002 GST_OBJECT_UNLOCK (pad);
3003 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad was flushing");
3004 return GST_FLOW_WRONG_STATE;
3008 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3009 "alloc function returned error (%d) %s", ret, gst_flow_get_name (ret));
3014 /* fallback case, allocate a buffer of our own, add pad caps. */
3015 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "fallback buffer alloc");
3017 if ((*buf = gst_buffer_try_new_and_alloc (size))) {
3018 GST_BUFFER_OFFSET (*buf) = offset;
3019 gst_buffer_set_caps (*buf, caps);
3022 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3023 "out of memory allocating %d bytes", size);
3024 return GST_FLOW_ERROR;
3029 /* FIXME 0.11: size should be unsigned */
3030 static GstFlowReturn
3031 gst_pad_alloc_buffer_full (GstPad * pad, guint64 offset, gint size,
3032 GstCaps * caps, GstBuffer ** buf, gboolean setcaps)
3037 gboolean caps_changed;
3039 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
3040 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
3041 g_return_val_if_fail (buf != NULL, GST_FLOW_ERROR);
3042 g_return_val_if_fail (size >= 0, GST_FLOW_ERROR);
3044 GST_DEBUG_OBJECT (pad, "offset %" G_GUINT64_FORMAT ", size %d, caps %"
3045 GST_PTR_FORMAT, offset, size, caps);
3047 GST_OBJECT_LOCK (pad);
3048 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
3049 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
3052 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
3055 gst_object_ref (peer);
3056 GST_OBJECT_UNLOCK (pad);
3058 ret = gst_pad_buffer_alloc_unchecked (peer, offset, size, caps, buf);
3059 gst_object_unref (peer);
3061 if (G_UNLIKELY (ret != GST_FLOW_OK))
3064 /* FIXME, move capnego this into a base class? */
3065 newcaps = GST_BUFFER_CAPS (*buf);
3067 /* Lock for checking caps, pretty pointless as the _pad_push() function might
3068 * change it concurrently, one of the problems with automatic caps setting in
3069 * pad_alloc_and_set_caps. Worst case, if does a check too much, but only
3070 * when there is heavy renegotiation going on in both directions. */
3071 GST_OBJECT_LOCK (pad);
3072 caps_changed = newcaps && newcaps != GST_PAD_CAPS (pad);
3073 GST_OBJECT_UNLOCK (pad);
3075 /* we got a new datatype on the pad, see if it can handle it */
3076 if (G_UNLIKELY (caps_changed)) {
3077 GST_DEBUG_OBJECT (pad,
3078 "caps changed from %" GST_PTR_FORMAT " to %p %" GST_PTR_FORMAT,
3079 GST_PAD_CAPS (pad), newcaps, newcaps);
3080 if (G_UNLIKELY (!gst_pad_configure_src (pad, newcaps, setcaps)))
3081 goto not_negotiated;
3084 /* sanity check (only if caps are the same) */
3085 if (G_LIKELY (newcaps == caps) && G_UNLIKELY (GST_BUFFER_SIZE (*buf) < size))
3086 goto wrong_size_fallback;
3092 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "pad block stopped by flush");
3093 GST_OBJECT_UNLOCK (pad);
3098 /* pad has no peer */
3099 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3100 "called bufferallocfunc but had no peer");
3101 GST_OBJECT_UNLOCK (pad);
3102 return GST_FLOW_NOT_LINKED;
3106 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3107 "alloc function returned error %s", gst_flow_get_name (ret));
3112 gst_buffer_unref (*buf);
3114 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
3115 "alloc function returned unacceptable buffer");
3116 return GST_FLOW_NOT_NEGOTIATED;
3118 wrong_size_fallback:
3120 GST_CAT_ERROR_OBJECT (GST_CAT_PADS, pad, "buffer returned by alloc "
3121 "function is too small (%u < %d), doing fallback buffer alloc",
3122 GST_BUFFER_SIZE (*buf), size);
3124 gst_buffer_unref (*buf);
3126 if ((*buf = gst_buffer_try_new_and_alloc (size))) {
3127 GST_BUFFER_OFFSET (*buf) = offset;
3128 gst_buffer_set_caps (*buf, caps);
3131 GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
3132 "out of memory allocating %d bytes", size);
3133 return GST_FLOW_ERROR;
3139 * gst_pad_alloc_buffer:
3140 * @pad: a source #GstPad
3141 * @offset: the offset of the new buffer in the stream
3142 * @size: the size of the new buffer
3143 * @caps: the caps of the new buffer
3144 * @buf: a newly allocated buffer
3146 * Allocates a new, empty buffer optimized to push to pad @pad. This
3147 * function only works if @pad is a source pad and has a peer.
3149 * A new, empty #GstBuffer will be put in the @buf argument.
3150 * You need to check the caps of the buffer after performing this
3151 * function and renegotiate to the format if needed. If the caps changed, it is
3152 * possible that the buffer returned in @buf is not of the right size for the
3153 * new format, @buf needs to be unreffed and reallocated if this is the case.
3155 * Returns: a result code indicating success of the operation. Any
3156 * result code other than #GST_FLOW_OK is an error and @buf should
3158 * An error can occur if the pad is not connected or when the downstream
3159 * peer elements cannot provide an acceptable buffer.
3164 /* FIXME 0.11: size should be unsigned */
3166 gst_pad_alloc_buffer (GstPad * pad, guint64 offset, gint size, GstCaps * caps,
3169 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, FALSE);
3173 * gst_pad_alloc_buffer_and_set_caps:
3174 * @pad: a source #GstPad
3175 * @offset: the offset of the new buffer in the stream
3176 * @size: the size of the new buffer
3177 * @caps: the caps of the new buffer
3178 * @buf: a newly allocated buffer
3180 * In addition to the function gst_pad_alloc_buffer(), this function
3181 * automatically calls gst_pad_set_caps() when the caps of the
3182 * newly allocated buffer are different from the @pad caps.
3184 * After a renegotiation, the size of the new buffer returned in @buf could
3185 * be of the wrong size for the new format and must be unreffed an reallocated
3188 * Returns: a result code indicating success of the operation. Any
3189 * result code other than #GST_FLOW_OK is an error and @buf should
3191 * An error can occur if the pad is not connected or when the downstream
3192 * peer elements cannot provide an acceptable buffer.
3197 /* FIXME 0.11: size should be unsigned */
3199 gst_pad_alloc_buffer_and_set_caps (GstPad * pad, guint64 offset, gint size,
3200 GstCaps * caps, GstBuffer ** buf)
3202 return gst_pad_alloc_buffer_full (pad, offset, size, caps, buf, TRUE);
3206 #ifndef GST_REMOVE_DEPRECATED
3214 int_link_iter_data_free (IntLinkIterData * data)
3216 g_list_free (data->list);
3217 g_slice_free (IntLinkIterData, data);
3221 static GstIteratorItem
3222 iterate_pad (GstIterator * it, GstPad * pad)
3224 gst_object_ref (pad);
3225 return GST_ITERATOR_ITEM_PASS;
3229 * gst_pad_iterate_internal_links_default:
3230 * @pad: the #GstPad to get the internal links of.
3232 * Iterate the list of pads to which the given pad is linked to inside of
3233 * the parent element.
3234 * This is the default handler, and thus returns an iterator of all of the
3235 * pads inside the parent element with opposite direction.
3237 * The caller must free this iterator after use with gst_iterator_free().
3239 * Returns: a #GstIterator of #GstPad, or NULL if @pad has no parent. Unref each
3240 * returned pad with gst_object_unref().
3245 gst_pad_iterate_internal_links_default (GstPad * pad)
3252 GstIteratorDisposeFunction dispose;
3254 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3256 #ifndef GST_REMOVE_DEPRECATED
3257 /* when we get here, the default handler for the iterate links is called,
3258 * which means that the user has not installed a custom one. We first check if
3259 * there is maybe a custom legacy function we can call. */
3260 if (GST_PAD_INTLINKFUNC (pad) &&
3261 GST_PAD_INTLINKFUNC (pad) != gst_pad_get_internal_links_default) {
3262 IntLinkIterData *data;
3264 /* make an iterator for the list. We can't protect the list with a
3265 * cookie. If we would take the cookie of the parent element, we need to
3266 * have a parent, which is not required for GST_PAD_INTLINKFUNC(). We could
3267 * cache the per-pad list and invalidate the list when a new call to
3268 * INTLINKFUNC() returned a different list but then this would only work if
3269 * two concurrent iterators were used and the last iterator would still be
3270 * thread-unsafe. Just don't use this method anymore. */
3271 data = g_slice_new (IntLinkIterData);
3272 data->list = GST_PAD_INTLINKFUNC (pad) (pad);
3275 GST_WARNING_OBJECT (pad, "Making unsafe iterator");
3277 cookie = &data->cookie;
3278 padlist = &data->list;
3280 dispose = (GstIteratorDisposeFunction) int_link_iter_data_free;
3281 /* reuse the pad lock, it's all we have here */
3282 lock = GST_OBJECT_GET_LOCK (pad);
3288 GST_OBJECT_LOCK (pad);
3289 parent = GST_PAD_PARENT (pad);
3290 if (!parent || !GST_IS_ELEMENT (parent))
3293 gst_object_ref (parent);
3294 GST_OBJECT_UNLOCK (pad);
3296 if (pad->direction == GST_PAD_SRC)
3297 padlist = &parent->sinkpads;
3299 padlist = &parent->srcpads;
3301 GST_DEBUG_OBJECT (pad, "Making iterator");
3303 cookie = &parent->pads_cookie;
3305 dispose = (GstIteratorDisposeFunction) gst_object_unref;
3306 lock = GST_OBJECT_GET_LOCK (parent);
3309 res = gst_iterator_new_list (GST_TYPE_PAD,
3310 lock, cookie, padlist, owner, (GstIteratorItemFunction) iterate_pad,
3318 GST_OBJECT_UNLOCK (pad);
3319 GST_DEBUG_OBJECT (pad, "no parent element");
3325 * gst_pad_iterate_internal_links:
3326 * @pad: the GstPad to get the internal links of.
3328 * Gets an iterator for the pads to which the given pad is linked to inside
3329 * of the parent element.
3331 * Each #GstPad element yielded by the iterator will have its refcount increased,
3332 * so unref after use.
3334 * Returns: a new #GstIterator of #GstPad or %NULL when the pad does not have an
3335 * iterator function configured. Use gst_iterator_free() after usage.
3340 gst_pad_iterate_internal_links (GstPad * pad)
3342 GstIterator *res = NULL;
3344 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3346 if (GST_PAD_ITERINTLINKFUNC (pad))
3347 res = GST_PAD_ITERINTLINKFUNC (pad) (pad);
3352 #ifndef GST_REMOVE_DEPRECATED
3354 add_unref_pad_to_list (GstPad * pad, GList ** list)
3356 *list = g_list_prepend (*list, pad);
3357 gst_object_unref (pad);
3362 * gst_pad_get_internal_links_default:
3363 * @pad: the #GstPad to get the internal links of.
3365 * Gets a list of pads to which the given pad is linked to
3366 * inside of the parent element.
3367 * This is the default handler, and thus returns a list of all of the
3368 * pads inside the parent element with opposite direction.
3370 * The caller must free this list after use with g_list_free().
3372 * Returns: a newly allocated #GList of pads, or NULL if the pad has no parent.
3376 * Deprecated: This function does not ref the pads in the list so that they
3377 * could become invalid by the time the application accesses them. It's also
3378 * possible that the list changes while handling the pads, which the caller of
3379 * this function is unable to know. Use the thread-safe
3380 * gst_pad_iterate_internal_links_default() instead.
3382 #ifndef GST_REMOVE_DEPRECATED
3384 gst_pad_get_internal_links_default (GstPad * pad)
3389 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3391 GST_WARNING_OBJECT (pad, "Unsafe internal links used");
3393 /* when we get here, the default handler for get_internal_links is called,
3394 * which means that the user has not installed a custom one. We first check if
3395 * there is maybe a custom iterate function we can call. */
3396 if (GST_PAD_ITERINTLINKFUNC (pad) &&
3397 GST_PAD_ITERINTLINKFUNC (pad) != gst_pad_iterate_internal_links_default) {
3399 GstIteratorResult ires;
3400 gboolean done = FALSE;
3402 it = gst_pad_iterate_internal_links (pad);
3403 /* loop over the iterator and put all elements into a list, we also
3404 * immediatly unref them, which is bad. */
3406 ires = gst_iterator_foreach (it, (GFunc) add_unref_pad_to_list, &res);
3408 case GST_ITERATOR_OK:
3409 case GST_ITERATOR_DONE:
3410 case GST_ITERATOR_ERROR:
3413 case GST_ITERATOR_RESYNC:
3414 /* restart, discard previous list */
3415 gst_iterator_resync (it);
3422 gst_iterator_free (it);
3424 /* lock pad, check and ref parent */
3425 GST_OBJECT_LOCK (pad);
3426 parent = GST_PAD_PARENT (pad);
3427 if (!parent || !GST_IS_ELEMENT (parent))
3430 parent = gst_object_ref (parent);
3431 GST_OBJECT_UNLOCK (pad);
3433 /* now lock the parent while we copy the pads */
3434 GST_OBJECT_LOCK (parent);
3435 if (pad->direction == GST_PAD_SRC)
3436 res = g_list_copy (parent->sinkpads);
3438 res = g_list_copy (parent->srcpads);
3439 GST_OBJECT_UNLOCK (parent);
3441 gst_object_unref (parent);
3444 /* At this point pads can be changed and unreffed. Nothing we can do about it
3445 * because for compatibility reasons this function cannot ref the pads or
3446 * notify the app that the list changed. */
3452 GST_DEBUG_OBJECT (pad, "no parent");
3453 GST_OBJECT_UNLOCK (pad);
3457 #endif /* GST_REMOVE_DEPRECATED */
3460 * gst_pad_get_internal_links:
3461 * @pad: the #GstPad to get the internal links of.
3463 * Gets a list of pads to which the given pad is linked to
3464 * inside of the parent element.
3465 * The caller must free this list after use.
3469 * Returns: a newly allocated #GList of pads, free with g_list_free().
3471 * Deprecated: This function does not ref the pads in the list so that they
3472 * could become invalid by the time the application accesses them. It's also
3473 * possible that the list changes while handling the pads, which the caller of
3474 * this function is unable to know. Use the thread-safe
3475 * gst_pad_iterate_internal_links() instead.
3477 #ifndef GST_REMOVE_DEPRECATED
3478 #ifdef GST_DISABLE_DEPRECATED
3479 GList *gst_pad_get_internal_links (GstPad * pad);
3482 gst_pad_get_internal_links (GstPad * pad)
3486 g_return_val_if_fail (GST_IS_PAD (pad), NULL);
3488 GST_WARNING_OBJECT (pad, "Calling unsafe internal links");
3490 if (GST_PAD_INTLINKFUNC (pad))
3491 res = GST_PAD_INTLINKFUNC (pad) (pad);
3495 #endif /* GST_REMOVE_DEPRECATED */
3498 gst_pad_event_default_dispatch (GstPad * pad, GstEvent * event)
3500 gboolean result = FALSE;
3502 gboolean done = FALSE;
3505 GList *pushed_pads = NULL;
3507 GST_INFO_OBJECT (pad, "Sending event %p (%s) to all internally linked pads",
3508 event, GST_EVENT_TYPE_NAME (event));
3510 iter = gst_pad_iterate_internal_links (pad);
3516 switch (gst_iterator_next (iter, &item)) {
3517 case GST_ITERATOR_OK:
3518 eventpad = GST_PAD_CAST (item);
3520 /* if already pushed, skip */
3521 if (g_list_find (pushed_pads, eventpad)) {
3522 gst_object_unref (item);
3526 if (GST_PAD_IS_SRC (eventpad)) {
3527 /* for each pad we send to, we should ref the event; it's up
3528 * to downstream to unref again when handled. */
3529 GST_LOG_OBJECT (pad, "Reffing and sending event %p (%s) to %s:%s",
3530 event, GST_EVENT_TYPE_NAME (event),
3531 GST_DEBUG_PAD_NAME (eventpad));
3532 gst_event_ref (event);
3533 result |= gst_pad_push_event (eventpad, event);
3535 /* we only send the event on one pad, multi-sinkpad elements
3536 * should implement a handler */
3537 GST_LOG_OBJECT (pad, "sending event %p (%s) to one sink pad %s:%s",
3538 event, GST_EVENT_TYPE_NAME (event),
3539 GST_DEBUG_PAD_NAME (eventpad));
3540 result = gst_pad_push_event (eventpad, event);
3545 pushed_pads = g_list_prepend (pushed_pads, eventpad);
3547 gst_object_unref (item);
3549 case GST_ITERATOR_RESYNC:
3550 /* FIXME, if we want to reset the result value we need to remember which
3551 * pads pushed with which result */
3552 gst_iterator_resync (iter);
3554 case GST_ITERATOR_ERROR:
3555 GST_ERROR_OBJECT (pad, "Could not iterate over internally linked pads");
3558 case GST_ITERATOR_DONE:
3563 gst_iterator_free (iter);
3567 /* If this is a sinkpad and we don't have pads to send the event to, we
3568 * return TRUE. This is so that when using the default handler on a sink
3569 * element, we don't fail to push it. */
3571 result = GST_PAD_IS_SINK (pad);
3573 g_list_free (pushed_pads);
3575 /* we handled the incoming event so we unref once */
3577 GST_LOG_OBJECT (pad, "handled event %p, unreffing", event);
3578 gst_event_unref (event);
3585 * gst_pad_event_default:
3586 * @pad: a #GstPad to call the default event handler on.
3587 * @event: the #GstEvent to handle.
3589 * Invokes the default event handler for the given pad. End-of-stream and
3590 * discontinuity events are handled specially, and then the event is sent to all
3591 * pads internally linked to @pad. Note that if there are many possible sink
3592 * pads that are internally linked to @pad, only one will be sent an event.
3593 * Multi-sinkpad elements should implement custom event handlers.
3595 * Returns: TRUE if the event was sent succesfully.
3598 gst_pad_event_default (GstPad * pad, GstEvent * event)
3600 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3601 g_return_val_if_fail (event != NULL, FALSE);
3603 GST_LOG_OBJECT (pad, "default event handler");
3605 switch (GST_EVENT_TYPE (event)) {
3608 GST_DEBUG_OBJECT (pad, "pausing task because of eos");
3609 gst_pad_pause_task (pad);
3616 return gst_pad_event_default_dispatch (pad, event);
3620 * gst_pad_dispatcher:
3621 * @pad: a #GstPad to dispatch.
3622 * @dispatch: the #GstPadDispatcherFunction to call.
3623 * @data: gpointer user data passed to the dispatcher function.
3625 * Invokes the given dispatcher function on each respective peer of
3626 * all pads that are internally linked to the given pad.
3627 * The GstPadDispatcherFunction should return TRUE when no further pads
3628 * need to be processed.
3630 * Returns: TRUE if one of the dispatcher functions returned TRUE.
3633 gst_pad_dispatcher (GstPad * pad, GstPadDispatcherFunction dispatch,
3636 gboolean res = FALSE;
3637 GstIterator *iter = NULL;
3638 gboolean done = FALSE;
3641 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3642 g_return_val_if_fail (dispatch != NULL, FALSE);
3644 iter = gst_pad_iterate_internal_links (pad);
3650 switch (gst_iterator_next (iter, &item)) {
3651 case GST_ITERATOR_OK:
3653 GstPad *int_pad = GST_PAD_CAST (item);
3654 GstPad *int_peer = gst_pad_get_peer (int_pad);
3657 GST_DEBUG_OBJECT (int_pad, "dispatching to peer %s:%s",
3658 GST_DEBUG_PAD_NAME (int_peer));
3659 done = res = dispatch (int_peer, data);
3660 gst_object_unref (int_peer);
3662 GST_DEBUG_OBJECT (int_pad, "no peer");
3665 gst_object_unref (item);
3667 case GST_ITERATOR_RESYNC:
3668 gst_iterator_resync (iter);
3670 case GST_ITERATOR_ERROR:
3672 GST_ERROR_OBJECT (pad, "Could not iterate internally linked pads");
3674 case GST_ITERATOR_DONE:
3679 gst_iterator_free (iter);
3681 GST_DEBUG_OBJECT (pad, "done, result %d", res);
3690 * @pad: a #GstPad to invoke the default query on.
3691 * @query: the #GstQuery to perform.
3693 * Dispatches a query to a pad. The query should have been allocated by the
3694 * caller via one of the type-specific allocation functions. The element that
3695 * the pad belongs to is responsible for filling the query with an appropriate
3696 * response, which should then be parsed with a type-specific query parsing
3699 * Again, the caller is responsible for both the allocation and deallocation of
3700 * the query structure.
3702 * Please also note that some queries might need a running pipeline to work.
3704 * Returns: TRUE if the query could be performed.
3707 gst_pad_query (GstPad * pad, GstQuery * query)
3709 GstPadQueryFunction func;
3711 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3712 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
3714 GST_DEBUG_OBJECT (pad, "sending query %p", query);
3716 if ((func = GST_PAD_QUERYFUNC (pad)) == NULL)
3719 return func (pad, query);
3723 GST_DEBUG_OBJECT (pad, "had no query function");
3729 * gst_pad_peer_query:
3730 * @pad: a #GstPad to invoke the peer query on.
3731 * @query: the #GstQuery to perform.
3733 * Performs gst_pad_query() on the peer of @pad.
3735 * The caller is responsible for both the allocation and deallocation of
3736 * the query structure.
3738 * Returns: TRUE if the query could be performed. This function returns %FALSE
3739 * if @pad has no peer.
3744 gst_pad_peer_query (GstPad * pad, GstQuery * query)
3749 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
3750 g_return_val_if_fail (GST_IS_QUERY (query), FALSE);
3752 GST_OBJECT_LOCK (pad);
3754 GST_DEBUG_OBJECT (pad, "peer query");
3756 peerpad = GST_PAD_PEER (pad);
3757 if (G_UNLIKELY (peerpad == NULL))
3760 gst_object_ref (peerpad);
3761 GST_OBJECT_UNLOCK (pad);
3763 result = gst_pad_query (peerpad, query);
3765 gst_object_unref (peerpad);
3772 GST_WARNING_OBJECT (pad, "pad has no peer");
3773 GST_OBJECT_UNLOCK (pad);
3779 * gst_pad_query_default:
3780 * @pad: a #GstPad to call the default query handler on.
3781 * @query: the #GstQuery to handle.
3783 * Invokes the default query handler for the given pad.
3784 * The query is sent to all pads internally linked to @pad. Note that
3785 * if there are many possible sink pads that are internally linked to
3786 * @pad, only one will be sent the query.
3787 * Multi-sinkpad elements should implement custom query handlers.
3789 * Returns: TRUE if the query was performed succesfully.
3792 gst_pad_query_default (GstPad * pad, GstQuery * query)
3794 switch (GST_QUERY_TYPE (query)) {
3795 case GST_QUERY_POSITION:
3796 case GST_QUERY_SEEKING:
3797 case GST_QUERY_FORMATS:
3798 case GST_QUERY_LATENCY:
3799 case GST_QUERY_JITTER:
3800 case GST_QUERY_RATE:
3801 case GST_QUERY_CONVERT:
3803 return gst_pad_dispatcher
3804 (pad, (GstPadDispatcherFunction) gst_pad_query, query);
3808 #if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
3809 /* FIXME: why isn't this on a GstElement ? */
3811 * gst_pad_load_and_link:
3812 * @self: an #xmlNodePtr to read the description from.
3813 * @parent: the #GstObject element that owns the pad.
3815 * Reads the pad definition from the XML node and links the given pad
3816 * in the element to a pad of an element up in the hierarchy.
3819 gst_pad_load_and_link (xmlNodePtr self, GstObject * parent)
3821 xmlNodePtr field = self->xmlChildrenNode;
3822 GstPad *pad = NULL, *targetpad;
3823 GstPadTemplate *tmpl;
3827 GstObject *grandparent;
3831 if (!strcmp ((char *) field->name, "name")) {
3832 name = (gchar *) xmlNodeGetContent (field);
3833 pad = gst_element_get_static_pad (GST_ELEMENT (parent), name);
3834 if ((!pad) || ((tmpl = gst_pad_get_pad_template (pad))
3835 && (GST_PAD_REQUEST == GST_PAD_TEMPLATE_PRESENCE (tmpl))))
3836 pad = gst_element_get_request_pad (GST_ELEMENT (parent), name);
3838 } else if (!strcmp ((char *) field->name, "peer")) {
3839 peer = (gchar *) xmlNodeGetContent (field);
3841 field = field->next;
3843 g_return_if_fail (pad != NULL);
3848 split = g_strsplit (peer, ".", 2);
3850 if (split[0] == NULL || split[1] == NULL) {
3851 GST_CAT_DEBUG_OBJECT (GST_CAT_XML, pad,
3852 "Could not parse peer '%s', leaving unlinked", peer);
3859 g_return_if_fail (split[0] != NULL);
3860 g_return_if_fail (split[1] != NULL);
3862 grandparent = gst_object_get_parent (parent);
3864 if (grandparent && GST_IS_BIN (grandparent)) {
3865 target = gst_bin_get_by_name_recurse_up (GST_BIN (grandparent), split[0]);
3872 targetpad = gst_element_get_static_pad (target, split[1]);
3874 targetpad = gst_element_get_request_pad (target, split[1]);
3876 if (targetpad == NULL)
3879 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
3880 gst_pad_link (pad, targetpad);
3882 gst_pad_link (targetpad, pad);
3889 * gst_pad_save_thyself:
3890 * @pad: a #GstPad to save.
3891 * @parent: the parent #xmlNodePtr to save the description in.
3893 * Saves the pad into an xml representation.
3895 * Returns: the #xmlNodePtr representation of the pad.
3898 gst_pad_save_thyself (GstObject * object, xmlNodePtr parent)
3903 g_return_val_if_fail (GST_IS_PAD (object), NULL);
3905 pad = GST_PAD_CAST (object);
3907 xmlNewChild (parent, NULL, (xmlChar *) "name",
3908 (xmlChar *) GST_PAD_NAME (pad));
3910 if (GST_PAD_IS_SRC (pad)) {
3911 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "source");
3912 } else if (GST_PAD_IS_SINK (pad)) {
3913 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "sink");
3915 xmlNewChild (parent, NULL, (xmlChar *) "direction", (xmlChar *) "unknown");
3918 if (GST_PAD_PEER (pad) != NULL) {
3921 peer = GST_PAD_PEER (pad);
3922 /* first check to see if the peer's parent's parent is the same */
3923 /* we just save it off */
3924 content = g_strdup_printf ("%s.%s",
3925 GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
3926 xmlNewChild (parent, NULL, (xmlChar *) "peer", (xmlChar *) content);
3929 xmlNewChild (parent, NULL, (xmlChar *) "peer", NULL);
3936 * gst_ghost_pad_save_thyself:
3937 * @pad: a ghost #GstPad to save.
3938 * @parent: the parent #xmlNodePtr to save the description in.
3940 * Saves the ghost pad into an xml representation.
3942 * Returns: the #xmlNodePtr representation of the pad.
3945 gst_ghost_pad_save_thyself (GstPad * pad, xmlNodePtr parent)
3949 g_return_val_if_fail (GST_IS_GHOST_PAD (pad), NULL);
3951 self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
3952 xmlNewChild (self, NULL, (xmlChar *) "name", (xmlChar *) GST_PAD_NAME (pad));
3953 xmlNewChild (self, NULL, (xmlChar *) "parent",
3954 (xmlChar *) GST_OBJECT_NAME (GST_PAD_PARENT (pad)));
3956 /* FIXME FIXME FIXME! */
3961 #endif /* GST_DISABLE_LOADSAVE */
3964 * should be called with pad OBJECT_LOCK and STREAM_LOCK held.
3965 * GST_PAD_IS_BLOCKED (pad) == TRUE when this function is
3968 * This function performs the pad blocking when an event, buffer push
3969 * or buffer_alloc is performed on a _SRC_ pad. It blocks the
3970 * streaming thread after informing the pad has been blocked.
3972 * An application can with this method wait and block any streaming
3973 * thread and perform operations such as seeking or linking.
3975 * Two methods are available for notifying the application of the
3977 * - the callback method, which happens in the STREAMING thread with
3978 * the STREAM_LOCK held. With this method, the most useful way of
3979 * dealing with the callback is to post a message to the main thread
3980 * where the pad block can then be handled outside of the streaming
3981 * thread. With the last method one can perform all operations such
3982 * as doing a state change, linking, unblocking, seeking etc on the
3984 * - the GCond signal method, which makes any thread unblock when
3985 * the pad block happens.
3987 * During the actual blocking state, the GST_PAD_BLOCKING flag is set.
3988 * The GST_PAD_BLOCKING flag is unset when the pad was unblocked.
3992 static GstFlowReturn
3993 handle_pad_block (GstPad * pad)
3995 GstPadBlockCallback callback;
3997 GstFlowReturn ret = GST_FLOW_OK;
3999 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "signal block taken");
4001 /* flushing, don't bother trying to block and return WRONG_STATE
4003 if (GST_PAD_IS_FLUSHING (pad))
4004 goto flushingnonref;
4006 /* we grab an extra ref for the callbacks, this is probably not
4007 * needed (callback code does not have a ref and cannot unref). I
4008 * think this was done to make it possible to unref the element in
4009 * the callback, which is in the end totally impossible as it
4010 * requires grabbing the STREAM_LOCK and OBJECT_LOCK which are
4011 * all taken when calling this function. */
4012 gst_object_ref (pad);
4014 while (GST_PAD_IS_BLOCKED (pad)) {
4016 /* we either have a callback installed to notify the block or
4017 * some other thread is doing a GCond wait. */
4018 callback = pad->block_callback;
4019 pad->abidata.ABI.block_callback_called = TRUE;
4021 /* there is a callback installed, call it. We release the
4022 * lock so that the callback can do something usefull with the
4024 user_data = pad->block_data;
4025 GST_OBJECT_UNLOCK (pad);
4026 callback (pad, TRUE, user_data);
4027 GST_OBJECT_LOCK (pad);
4029 /* we released the lock, recheck flushing */
4030 if (GST_PAD_IS_FLUSHING (pad))
4033 /* no callback, signal the thread that is doing a GCond wait
4035 GST_PAD_BLOCK_BROADCAST (pad);
4037 } while (pad->abidata.ABI.block_callback_called == FALSE
4038 && GST_PAD_IS_BLOCKED (pad));
4040 /* OBJECT_LOCK could have been released when we did the callback, which
4041 * then could have made the pad unblock so we need to check the blocking
4042 * condition again. */
4043 if (!GST_PAD_IS_BLOCKED (pad))
4046 /* now we block the streaming thread. It can be unlocked when we
4047 * deactivate the pad (which will also set the FLUSHING flag) or
4048 * when the pad is unblocked. A flushing event will also unblock
4049 * the pad after setting the FLUSHING flag. */
4050 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4051 "Waiting to be unblocked or set flushing");
4052 GST_OBJECT_FLAG_SET (pad, GST_PAD_BLOCKING);
4053 GST_PAD_BLOCK_WAIT (pad);
4054 GST_OBJECT_FLAG_UNSET (pad, GST_PAD_BLOCKING);
4056 /* see if we got unblocked by a flush or not */
4057 if (GST_PAD_IS_FLUSHING (pad))
4061 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got unblocked");
4063 /* when we get here, the pad is unblocked again and we perform
4064 * the needed unblock code. */
4065 callback = pad->block_callback;
4067 /* we need to call the callback */
4068 user_data = pad->block_data;
4069 GST_OBJECT_UNLOCK (pad);
4070 callback (pad, FALSE, user_data);
4071 GST_OBJECT_LOCK (pad);
4073 /* we need to signal the thread waiting on the GCond */
4074 GST_PAD_BLOCK_BROADCAST (pad);
4077 gst_object_unref (pad);
4083 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad was flushing");
4084 return GST_FLOW_WRONG_STATE;
4088 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "pad became flushing");
4089 gst_object_unref (pad);
4090 return GST_FLOW_WRONG_STATE;
4094 /**********************************************************************
4095 * Data passing functions
4099 gst_pad_emit_have_data_signal (GstPad * pad, GstMiniObject * obj)
4102 GValue args[2] = { {0}, {0} };
4107 g_value_init (&ret, G_TYPE_BOOLEAN);
4108 g_value_set_boolean (&ret, TRUE);
4109 g_value_init (&args[0], GST_TYPE_PAD);
4110 g_value_set_object (&args[0], pad);
4111 g_value_init (&args[1], GST_TYPE_MINI_OBJECT);
4112 gst_value_set_mini_object (&args[1], obj);
4114 if (GST_IS_EVENT (obj))
4115 detail = event_quark;
4117 detail = buffer_quark;
4120 g_signal_emitv (args, gst_pad_signals[PAD_HAVE_DATA], detail, &ret);
4121 res = g_value_get_boolean (&ret);
4124 g_value_unset (&ret);
4125 g_value_unset (&args[0]);
4126 g_value_unset (&args[1]);
4132 gst_pad_data_unref (gboolean is_buffer, void *data)
4134 if (G_LIKELY (is_buffer)) {
4135 gst_buffer_unref (data);
4137 gst_buffer_list_unref (data);
4142 gst_pad_data_get_caps (gboolean is_buffer, void *data)
4146 if (G_LIKELY (is_buffer)) {
4147 caps = GST_BUFFER_CAPS (data);
4151 if ((buf = gst_buffer_list_get (GST_BUFFER_LIST_CAST (data), 0, 0)))
4152 caps = GST_BUFFER_CAPS (buf);
4159 /* this is the chain function that does not perform the additional argument
4160 * checking for that little extra speed.
4162 static inline GstFlowReturn
4163 gst_pad_chain_data_unchecked (GstPad * pad, gboolean is_buffer, void *data,
4164 GstPadPushCache * cache)
4167 gboolean caps_changed;
4169 gboolean emit_signal;
4171 GST_PAD_STREAM_LOCK (pad);
4173 GST_OBJECT_LOCK (pad);
4174 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4177 caps = gst_pad_data_get_caps (is_buffer, data);
4178 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4180 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4181 GST_OBJECT_UNLOCK (pad);
4183 /* see if the signal should be emited, we emit before caps nego as
4184 * we might drop the buffer and do capsnego for nothing. */
4185 if (G_UNLIKELY (emit_signal)) {
4187 if (G_LIKELY (is_buffer)) {
4188 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (data)))
4191 /* chain all groups in the buffer list one by one to avoid problems with
4192 * buffer probes that push buffers or events */
4197 /* we got a new datatype on the pad, see if it can handle it */
4198 if (G_UNLIKELY (caps_changed)) {
4199 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
4200 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
4201 goto not_negotiated;
4204 /* NOTE: we read the chainfunc unlocked.
4205 * we cannot hold the lock for the pad so we might send
4206 * the data to the wrong function. This is not really a
4207 * problem since functions are assigned at creation time
4208 * and don't change that often... */
4209 if (G_LIKELY (is_buffer)) {
4210 GstPadChainFunction chainfunc;
4212 if (G_UNLIKELY ((chainfunc = GST_PAD_CHAINFUNC (pad)) == NULL))
4215 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4216 "calling chainfunction &%s", GST_DEBUG_FUNCPTR_NAME (chainfunc));
4219 cache->peer = gst_object_ref (pad);
4220 cache->caps = caps ? gst_caps_ref (caps) : NULL;
4221 cache->chainfunc = chainfunc;
4224 ret = chainfunc (pad, GST_BUFFER_CAST (data));
4226 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4227 "called chainfunction &%s, returned %s",
4228 GST_DEBUG_FUNCPTR_NAME (chainfunc), gst_flow_get_name (ret));
4230 GstPadChainListFunction chainlistfunc;
4232 if (G_UNLIKELY ((chainlistfunc = GST_PAD_CHAINLISTFUNC (pad)) == NULL))
4235 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4236 "calling chainlistfunction &%s",
4237 GST_DEBUG_FUNCPTR_NAME (chainlistfunc));
4239 ret = chainlistfunc (pad, GST_BUFFER_LIST_CAST (data));
4241 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4242 "called chainlistfunction &%s, returned %s",
4243 GST_DEBUG_FUNCPTR_NAME (chainlistfunc), gst_flow_get_name (ret));
4246 GST_PAD_STREAM_UNLOCK (pad);
4252 GstBufferList *list;
4253 GstBufferListIterator *it;
4256 GST_PAD_STREAM_UNLOCK (pad);
4258 GST_INFO_OBJECT (pad, "chaining each group in list as a merged buffer");
4260 list = GST_BUFFER_LIST_CAST (data);
4261 it = gst_buffer_list_iterate (list);
4263 if (gst_buffer_list_iterator_next_group (it)) {
4265 group = gst_buffer_list_iterator_merge_group (it);
4266 if (group == NULL) {
4267 group = gst_buffer_new ();
4268 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining empty group");
4270 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining group");
4272 ret = gst_pad_chain_data_unchecked (pad, TRUE, group, NULL);
4273 } while (ret == GST_FLOW_OK && gst_buffer_list_iterator_next_group (it));
4275 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "chaining empty group");
4276 ret = gst_pad_chain_data_unchecked (pad, TRUE, gst_buffer_new (), NULL);
4279 gst_buffer_list_iterator_free (it);
4280 gst_buffer_list_unref (list);
4288 gst_pad_data_unref (is_buffer, data);
4289 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4290 "pushing, but pad was flushing");
4291 GST_OBJECT_UNLOCK (pad);
4292 GST_PAD_STREAM_UNLOCK (pad);
4293 return GST_FLOW_WRONG_STATE;
4297 gst_pad_data_unref (is_buffer, data);
4298 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
4299 GST_PAD_STREAM_UNLOCK (pad);
4304 gst_pad_data_unref (is_buffer, data);
4305 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4306 "pushing data but pad did not accept");
4307 GST_PAD_STREAM_UNLOCK (pad);
4308 return GST_FLOW_NOT_NEGOTIATED;
4312 gst_pad_data_unref (is_buffer, data);
4313 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4314 "pushing, but not chainhandler");
4315 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
4316 ("push on pad %s:%s but it has no chainfunction",
4317 GST_DEBUG_PAD_NAME (pad)));
4318 GST_PAD_STREAM_UNLOCK (pad);
4319 return GST_FLOW_NOT_SUPPORTED;
4325 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4326 * @buffer: the #GstBuffer to send, return GST_FLOW_ERROR if not.
4328 * Chain a buffer to @pad.
4330 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
4332 * If the caps on @buffer are different from the current caps on @pad, this
4333 * function will call any setcaps function (see gst_pad_set_setcaps_function())
4334 * installed on @pad. If the new caps are not acceptable for @pad, this
4335 * function returns #GST_FLOW_NOT_NEGOTIATED.
4337 * The function proceeds calling the chain function installed on @pad (see
4338 * gst_pad_set_chain_function()) and the return value of that function is
4339 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
4342 * In all cases, success or failure, the caller loses its reference to @buffer
4343 * after calling this function.
4345 * Returns: a #GstFlowReturn from the pad.
4350 gst_pad_chain (GstPad * pad, GstBuffer * buffer)
4352 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4353 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4354 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
4356 return gst_pad_chain_data_unchecked (pad, TRUE, buffer, NULL);
4360 * gst_pad_chain_list:
4361 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4362 * @list: the #GstBufferList to send, return GST_FLOW_ERROR if not.
4364 * Chain a bufferlist to @pad.
4366 * The function returns #GST_FLOW_WRONG_STATE if the pad was flushing.
4368 * If the caps on the first buffer of @list are different from the current
4369 * caps on @pad, this function will call any setcaps function
4370 * (see gst_pad_set_setcaps_function()) installed on @pad. If the new caps
4371 * are not acceptable for @pad, this function returns #GST_FLOW_NOT_NEGOTIATED.
4373 * The function proceeds calling the chainlist function installed on @pad (see
4374 * gst_pad_set_chain_list_function()) and the return value of that function is
4375 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
4376 * chainlist function.
4378 * In all cases, success or failure, the caller loses its reference to @list
4379 * after calling this function.
4383 * Returns: a #GstFlowReturn from the pad.
4388 gst_pad_chain_list (GstPad * pad, GstBufferList * list)
4390 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4391 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4392 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
4394 return gst_pad_chain_data_unchecked (pad, FALSE, list, NULL);
4397 static GstFlowReturn
4398 gst_pad_push_data (GstPad * pad, gboolean is_buffer, void *data,
4399 GstPadPushCache * cache)
4404 gboolean caps_changed;
4406 GST_OBJECT_LOCK (pad);
4408 /* FIXME: this check can go away; pad_set_blocked could be implemented with
4409 * probes completely or probes with an extended pad block. */
4410 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
4411 if ((ret = handle_pad_block (pad)) != GST_FLOW_OK)
4414 /* we emit signals on the pad arg, the peer will have a chance to
4415 * emit in the _chain() function */
4416 if (G_UNLIKELY (GST_PAD_DO_BUFFER_SIGNALS (pad) > 0)) {
4418 /* unlock before emitting */
4419 GST_OBJECT_UNLOCK (pad);
4421 if (G_LIKELY (is_buffer)) {
4422 /* if the signal handler returned FALSE, it means we should just drop the
4424 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (data)))
4427 /* push all buffers in the list */
4430 GST_OBJECT_LOCK (pad);
4433 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4436 /* Before pushing the buffer to the peer pad, ensure that caps
4437 * are set on this pad */
4438 caps = gst_pad_data_get_caps (is_buffer, data);
4439 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4441 /* take ref to peer pad before releasing the lock */
4442 gst_object_ref (peer);
4443 GST_OBJECT_UNLOCK (pad);
4445 /* we got a new datatype from the pad, it had better handle it */
4446 if (G_UNLIKELY (caps_changed)) {
4447 GST_DEBUG_OBJECT (pad,
4448 "caps changed from %" GST_PTR_FORMAT " to %p %" GST_PTR_FORMAT,
4449 GST_PAD_CAPS (pad), caps, caps);
4450 if (G_UNLIKELY (!gst_pad_set_caps (pad, caps)))
4451 goto not_negotiated;
4454 ret = gst_pad_chain_data_unchecked (peer, is_buffer, data, cache);
4456 gst_object_unref (peer);
4462 GstBufferList *list;
4463 GstBufferListIterator *it;
4466 GST_INFO_OBJECT (pad, "pushing each group in list as a merged buffer");
4468 list = GST_BUFFER_LIST_CAST (data);
4469 it = gst_buffer_list_iterate (list);
4471 if (gst_buffer_list_iterator_next_group (it)) {
4473 group = gst_buffer_list_iterator_merge_group (it);
4474 if (group == NULL) {
4475 group = gst_buffer_new ();
4476 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing empty group");
4478 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing group");
4480 ret = gst_pad_push_data (pad, TRUE, group, NULL);
4481 } while (ret == GST_FLOW_OK && gst_buffer_list_iterator_next_group (it));
4483 GST_CAT_INFO_OBJECT (GST_CAT_SCHEDULING, pad, "pushing empty group");
4484 ret = gst_pad_push_data (pad, TRUE, gst_buffer_new (), NULL);
4487 gst_buffer_list_iterator_free (it);
4488 gst_buffer_list_unref (list);
4493 /* ERROR recovery here */
4496 gst_pad_data_unref (is_buffer, data);
4497 GST_DEBUG_OBJECT (pad, "pad block stopped by flush");
4498 GST_OBJECT_UNLOCK (pad);
4503 gst_pad_data_unref (is_buffer, data);
4504 GST_DEBUG_OBJECT (pad, "Dropping buffer due to FALSE probe return");
4509 gst_pad_data_unref (is_buffer, data);
4510 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4511 "pushing, but it was not linked");
4512 GST_OBJECT_UNLOCK (pad);
4513 return GST_FLOW_NOT_LINKED;
4517 gst_pad_data_unref (is_buffer, data);
4518 gst_object_unref (peer);
4519 GST_CAT_DEBUG_OBJECT (GST_CAT_SCHEDULING, pad,
4520 "element pushed data then refused to accept the caps");
4521 return GST_FLOW_NOT_NEGOTIATED;
4525 static inline GstPadPushCache *
4526 pad_take_cache (GstPad * pad, gpointer * cache_ptr)
4528 GstPadPushCache *cache;
4530 /* try to get the cached data */
4532 cache = g_atomic_pointer_get (cache_ptr);
4533 /* now try to replace the pointer with NULL to mark that we are busy
4535 } while (!g_atomic_pointer_compare_and_exchange (cache_ptr, cache, NULL));
4537 /* we could have a leftover invalid entry */
4538 if (G_UNLIKELY (cache == PAD_CACHE_INVALID))
4545 pad_free_cache (GstPadPushCache * cache)
4547 gst_object_unref (cache->peer);
4549 gst_caps_unref (cache->caps);
4550 g_slice_free (GstPadPushCache, cache);
4554 pad_put_cache (GstPad * pad, GstPadPushCache * cache, gpointer * cache_ptr)
4557 if (!g_atomic_pointer_compare_and_exchange (cache_ptr, NULL, cache)) {
4558 /* something changed, clean up our cache */
4559 pad_free_cache (cache);
4563 /* must be called with the pad lock */
4565 pad_invalidate_cache (GstPad * pad)
4567 GstPadPushCache *cache;
4568 gpointer *cache_ptr;
4570 GST_LOG_OBJECT (pad, "Invalidating pad cache");
4572 /* we hold the pad lock here so we can get the peer and it stays
4573 * alive during this call */
4574 if (GST_PAD_IS_SINK (pad)) {
4575 if (!(pad = GST_PAD_PEER (pad)))
4579 cache_ptr = (gpointer *) & pad->abidata.ABI.priv->cache_ptr;
4581 /* try to get the cached data */
4583 cache = g_atomic_pointer_get (cache_ptr);
4584 /* now try to replace the pointer with INVALID. If nothing is busy with this
4585 * caps, we get the cache and clean it up. If something is busy, we replace
4586 * with INVALID so that when the function finishes and tries to put the
4587 * cache back, it'll fail and cleanup */
4588 } while (!g_atomic_pointer_compare_and_exchange (cache_ptr, cache,
4589 PAD_CACHE_INVALID));
4591 if (G_LIKELY (cache && cache != PAD_CACHE_INVALID))
4592 pad_free_cache (cache);
4597 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
4598 * @buffer: the #GstBuffer to push returns GST_FLOW_ERROR if not.
4600 * Pushes a buffer to the peer of @pad.
4602 * This function will call an installed pad block before triggering any
4603 * installed pad probes.
4605 * If the caps on @buffer are different from the currently configured caps on
4606 * @pad, this function will call any installed setcaps function on @pad (see
4607 * gst_pad_set_setcaps_function()). In case of failure to renegotiate the new
4608 * format, this function returns #GST_FLOW_NOT_NEGOTIATED.
4610 * The function proceeds calling gst_pad_chain() on the peer pad and returns
4611 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
4614 * In all cases, success or failure, the caller loses its reference to @buffer
4615 * after calling this function.
4617 * Returns: a #GstFlowReturn from the peer pad.
4622 gst_pad_push (GstPad * pad, GstBuffer * buffer)
4624 GstPadPushCache *cache;
4626 gpointer *cache_ptr;
4630 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4631 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4632 g_return_val_if_fail (GST_IS_BUFFER (buffer), GST_FLOW_ERROR);
4634 cache_ptr = (gpointer *) & pad->abidata.ABI.priv->cache_ptr;
4636 cache = pad_take_cache (pad, cache_ptr);
4638 if (G_UNLIKELY (cache == NULL))
4642 caps = GST_BUFFER_CAPS (buffer);
4643 if (G_UNLIKELY (caps && caps != cache->caps)) {
4644 pad_free_cache (cache);
4650 GST_PAD_STREAM_LOCK (peer);
4652 ret = cache->chainfunc (peer, buffer);
4654 GST_PAD_STREAM_UNLOCK (peer);
4656 pad_put_cache (pad, cache, cache_ptr);
4663 GstPadPushCache scache = { NULL, };
4665 GST_LOG_OBJECT (pad, "Taking slow path");
4667 ret = gst_pad_push_data (pad, TRUE, buffer, &scache);
4670 GstPadPushCache *ncache;
4672 GST_LOG_OBJECT (pad, "Caching push data");
4674 /* make cache structure */
4675 ncache = g_slice_new (GstPadPushCache);
4678 pad_put_cache (pad, ncache, cache_ptr);
4685 * gst_pad_push_list:
4686 * @pad: a source #GstPad, returns #GST_FLOW_ERROR if not.
4687 * @list: the #GstBufferList to push returns GST_FLOW_ERROR if not.
4689 * Pushes a buffer list to the peer of @pad.
4691 * This function will call an installed pad block before triggering any
4692 * installed pad probes.
4694 * If the caps on the first buffer in the first group of @list are different
4695 * from the currently configured caps on @pad, this function will call any
4696 * installed setcaps function on @pad (see gst_pad_set_setcaps_function()). In
4697 * case of failure to renegotiate the new format, this function returns
4698 * #GST_FLOW_NOT_NEGOTIATED.
4700 * If there are any probes installed on @pad every group of the buffer list
4701 * will be merged into a normal #GstBuffer and pushed via gst_pad_push and the
4702 * buffer list will be unreffed.
4704 * The function proceeds calling the chain function on the peer pad and returns
4705 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
4706 * be returned. If the peer pad does not have any installed chainlist function
4707 * every group buffer of the list will be merged into a normal #GstBuffer and
4708 * chained via gst_pad_chain().
4710 * In all cases, success or failure, the caller loses its reference to @list
4711 * after calling this function.
4713 * Returns: a #GstFlowReturn from the peer pad.
4720 gst_pad_push_list (GstPad * pad, GstBufferList * list)
4722 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4723 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4724 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), GST_FLOW_ERROR);
4726 return gst_pad_push_data (pad, FALSE, list, NULL);
4730 * gst_pad_check_pull_range:
4731 * @pad: a sink #GstPad.
4733 * Checks if a gst_pad_pull_range() can be performed on the peer
4734 * source pad. This function is used by plugins that want to check
4735 * if they can use random access on the peer source pad.
4737 * The peer sourcepad can implement a custom #GstPadCheckGetRangeFunction
4738 * if it needs to perform some logic to determine if pull_range is
4741 * Returns: a gboolean with the result.
4746 gst_pad_check_pull_range (GstPad * pad)
4750 GstPadCheckGetRangeFunction checkgetrangefunc;
4752 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
4754 GST_OBJECT_LOCK (pad);
4755 if (!GST_PAD_IS_SINK (pad))
4756 goto wrong_direction;
4758 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4761 gst_object_ref (peer);
4762 GST_OBJECT_UNLOCK (pad);
4764 /* see note in above function */
4765 if (G_LIKELY ((checkgetrangefunc = peer->checkgetrangefunc) == NULL)) {
4766 /* FIXME, kindoff ghetto */
4767 ret = GST_PAD_GETRANGEFUNC (peer) != NULL;
4768 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4769 "no checkgetrangefunc, assuming %d", ret);
4771 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4772 "calling checkgetrangefunc %s of peer pad %s:%s",
4773 GST_DEBUG_FUNCPTR_NAME (checkgetrangefunc), GST_DEBUG_PAD_NAME (peer));
4775 ret = checkgetrangefunc (peer);
4778 gst_object_unref (peer);
4782 /* ERROR recovery here */
4785 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4786 "checking pull range, but pad must be a sinkpad");
4787 GST_OBJECT_UNLOCK (pad);
4792 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4793 "checking pull range, but it was not linked");
4794 GST_OBJECT_UNLOCK (pad);
4799 static GstFlowReturn
4800 gst_pad_get_range_unchecked (GstPad * pad, guint64 offset, guint size,
4801 GstBuffer ** buffer)
4804 GstPadGetRangeFunction getrangefunc;
4805 gboolean emit_signal;
4807 gboolean caps_changed;
4809 GST_PAD_STREAM_LOCK (pad);
4811 GST_OBJECT_LOCK (pad);
4812 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
4815 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4816 GST_OBJECT_UNLOCK (pad);
4818 if (G_UNLIKELY ((getrangefunc = GST_PAD_GETRANGEFUNC (pad)) == NULL))
4821 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4822 "calling getrangefunc %s, offset %"
4823 G_GUINT64_FORMAT ", size %u",
4824 GST_DEBUG_FUNCPTR_NAME (getrangefunc), offset, size);
4826 ret = getrangefunc (pad, offset, size, buffer);
4828 /* can only fire the signal if we have a valid buffer */
4829 if (G_UNLIKELY (emit_signal) && (ret == GST_FLOW_OK)) {
4830 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
4834 GST_PAD_STREAM_UNLOCK (pad);
4836 if (G_UNLIKELY (ret != GST_FLOW_OK))
4837 goto get_range_failed;
4839 GST_OBJECT_LOCK (pad);
4840 /* Before pushing the buffer to the peer pad, ensure that caps
4841 * are set on this pad */
4842 caps = GST_BUFFER_CAPS (*buffer);
4843 caps_changed = caps && caps != GST_PAD_CAPS (pad);
4844 GST_OBJECT_UNLOCK (pad);
4846 if (G_UNLIKELY (caps_changed)) {
4847 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
4848 /* this should usually work because the element produced the buffer */
4849 if (G_UNLIKELY (!gst_pad_configure_src (pad, caps, TRUE)))
4850 goto not_negotiated;
4857 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4858 "pulling range, but pad was flushing");
4859 GST_OBJECT_UNLOCK (pad);
4860 GST_PAD_STREAM_UNLOCK (pad);
4861 return GST_FLOW_WRONG_STATE;
4865 GST_ELEMENT_ERROR (GST_PAD_PARENT (pad), CORE, PAD, (NULL),
4866 ("pullrange on pad %s:%s but it has no getrangefunction",
4867 GST_DEBUG_PAD_NAME (pad)));
4868 GST_PAD_STREAM_UNLOCK (pad);
4869 return GST_FLOW_NOT_SUPPORTED;
4873 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
4874 "Dropping data after FALSE probe return");
4875 GST_PAD_STREAM_UNLOCK (pad);
4876 gst_buffer_unref (*buffer);
4878 return GST_FLOW_UNEXPECTED;
4883 GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
4884 (ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
4885 pad, "getrange failed, flow: %s", gst_flow_get_name (ret));
4890 gst_buffer_unref (*buffer);
4892 GST_CAT_WARNING_OBJECT (GST_CAT_SCHEDULING, pad,
4893 "getrange returned buffer of unaccaptable caps");
4894 return GST_FLOW_NOT_NEGOTIATED;
4899 * gst_pad_get_range:
4900 * @pad: a src #GstPad, returns #GST_FLOW_ERROR if not.
4901 * @offset: The start offset of the buffer
4902 * @size: The length of the buffer
4903 * @buffer: a pointer to hold the #GstBuffer, returns #GST_FLOW_ERROR if %NULL.
4905 * When @pad is flushing this function returns #GST_FLOW_WRONG_STATE
4906 * immediatly and @buffer is %NULL.
4908 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
4909 * description of a getrange function. If @pad has no getrange function
4910 * installed (see gst_pad_set_getrange_function()) this function returns
4911 * #GST_FLOW_NOT_SUPPORTED.
4913 * This is a lowlevel function. Usualy gst_pad_pull_range() is used.
4915 * Returns: a #GstFlowReturn from the pad.
4920 gst_pad_get_range (GstPad * pad, guint64 offset, guint size,
4921 GstBuffer ** buffer)
4923 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4924 g_return_val_if_fail (GST_PAD_IS_SRC (pad), GST_FLOW_ERROR);
4925 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
4927 return gst_pad_get_range_unchecked (pad, offset, size, buffer);
4931 * gst_pad_pull_range:
4932 * @pad: a sink #GstPad, returns GST_FLOW_ERROR if not.
4933 * @offset: The start offset of the buffer
4934 * @size: The length of the buffer
4935 * @buffer: a pointer to hold the #GstBuffer, returns GST_FLOW_ERROR if %NULL.
4937 * Pulls a @buffer from the peer pad.
4939 * This function will first trigger the pad block signal if it was
4942 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
4943 * function returns the result of gst_pad_get_range() on the peer pad.
4944 * See gst_pad_get_range() for a list of return values and for the
4945 * semantics of the arguments of this function.
4947 * @buffer's caps must either be unset or the same as what is already
4948 * configured on @pad. Renegotiation within a running pull-mode pipeline is not
4951 * Returns: a #GstFlowReturn from the peer pad.
4952 * When this function returns #GST_FLOW_OK, @buffer will contain a valid
4953 * #GstBuffer that should be freed with gst_buffer_unref() after usage.
4954 * @buffer may not be used or freed when any other return value than
4955 * #GST_FLOW_OK is returned.
4960 gst_pad_pull_range (GstPad * pad, guint64 offset, guint size,
4961 GstBuffer ** buffer)
4965 gboolean emit_signal;
4967 gboolean caps_changed;
4969 g_return_val_if_fail (GST_IS_PAD (pad), GST_FLOW_ERROR);
4970 g_return_val_if_fail (GST_PAD_IS_SINK (pad), GST_FLOW_ERROR);
4971 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
4973 GST_OBJECT_LOCK (pad);
4975 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad)))
4976 handle_pad_block (pad);
4978 if (G_UNLIKELY ((peer = GST_PAD_PEER (pad)) == NULL))
4981 /* signal emision for the pad, peer has chance to emit when
4982 * we call _get_range() */
4983 emit_signal = GST_PAD_DO_BUFFER_SIGNALS (pad) > 0;
4985 gst_object_ref (peer);
4986 GST_OBJECT_UNLOCK (pad);
4988 ret = gst_pad_get_range_unchecked (peer, offset, size, buffer);
4990 gst_object_unref (peer);
4992 if (G_UNLIKELY (ret != GST_FLOW_OK))
4993 goto pull_range_failed;
4995 /* can only fire the signal if we have a valid buffer */
4996 if (G_UNLIKELY (emit_signal)) {
4997 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (*buffer)))
5001 GST_OBJECT_LOCK (pad);
5002 /* Before pushing the buffer to the peer pad, ensure that caps
5003 * are set on this pad */
5004 caps = GST_BUFFER_CAPS (*buffer);
5005 caps_changed = caps && caps != GST_PAD_CAPS (pad);
5006 GST_OBJECT_UNLOCK (pad);
5008 /* we got a new datatype on the pad, see if it can handle it */
5009 if (G_UNLIKELY (caps_changed)) {
5010 GST_DEBUG_OBJECT (pad, "caps changed to %p %" GST_PTR_FORMAT, caps, caps);
5011 if (G_UNLIKELY (!gst_pad_configure_sink (pad, caps)))
5012 goto not_negotiated;
5016 /* ERROR recovery here */
5019 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
5020 "pulling range, but it was not linked");
5021 GST_OBJECT_UNLOCK (pad);
5022 return GST_FLOW_NOT_LINKED;
5027 GST_CAT_LEVEL_LOG (GST_CAT_SCHEDULING,
5028 (ret >= GST_FLOW_UNEXPECTED) ? GST_LEVEL_INFO : GST_LEVEL_WARNING,
5029 pad, "pullrange failed, flow: %s", gst_flow_get_name (ret));
5034 GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
5035 "Dropping data after FALSE probe return");
5036 gst_buffer_unref (*buffer);
5038 return GST_FLOW_UNEXPECTED;
5042 gst_buffer_unref (*buffer);
5044 GST_CAT_WARNING_OBJECT (GST_CAT_SCHEDULING, pad,
5045 "pullrange returned buffer of different caps");
5046 return GST_FLOW_NOT_NEGOTIATED;
5051 * gst_pad_push_event:
5052 * @pad: a #GstPad to push the event to.
5053 * @event: the #GstEvent to send to the pad.
5055 * Sends the event to the peer of the given pad. This function is
5056 * mainly used by elements to send events to their peer
5059 * This function takes owership of the provided event so you should
5060 * gst_event_ref() it if you want to reuse the event after this call.
5062 * Returns: TRUE if the event was handled.
5067 gst_pad_push_event (GstPad * pad, GstEvent * event)
5072 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5073 g_return_val_if_fail (event != NULL, FALSE);
5074 g_return_val_if_fail (GST_IS_EVENT (event), FALSE);
5076 GST_LOG_OBJECT (pad, "event: %s", GST_EVENT_TYPE_NAME (event));
5078 GST_OBJECT_LOCK (pad);
5080 /* Two checks to be made:
5081 * . (un)set the FLUSHING flag for flushing events,
5082 * . handle pad blocking */
5083 switch (GST_EVENT_TYPE (event)) {
5084 case GST_EVENT_FLUSH_START:
5085 pad_invalidate_cache (pad);
5086 GST_PAD_SET_FLUSHING (pad);
5088 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
5089 /* flush start will have set the FLUSHING flag and will then
5090 * unlock all threads doing a GCond wait on the blocking pad. This
5091 * will typically unblock the STREAMING thread blocked on a pad. */
5092 GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-start, "
5093 "doing block signal.");
5094 GST_PAD_BLOCK_BROADCAST (pad);
5098 case GST_EVENT_FLUSH_STOP:
5099 GST_PAD_UNSET_FLUSHING (pad);
5101 /* if we are blocked, flush away the FLUSH_STOP event */
5102 if (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
5103 GST_LOG_OBJECT (pad, "Pad is blocked, not forwarding flush-stop");
5108 while (G_UNLIKELY (GST_PAD_IS_BLOCKED (pad))) {
5109 /* block the event as long as the pad is blocked */
5110 if (handle_pad_block (pad) != GST_FLOW_OK)
5116 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
5117 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
5118 GST_EVENT_SRC (event) = gst_object_ref (pad);
5121 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
5122 GST_OBJECT_UNLOCK (pad);
5124 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT (event)))
5127 GST_OBJECT_LOCK (pad);
5129 peerpad = GST_PAD_PEER (pad);
5130 if (peerpad == NULL)
5133 GST_LOG_OBJECT (pad, "sending event %s to peerpad %" GST_PTR_FORMAT,
5134 GST_EVENT_TYPE_NAME (event), peerpad);
5135 gst_object_ref (peerpad);
5136 GST_OBJECT_UNLOCK (pad);
5138 result = gst_pad_send_event (peerpad, event);
5140 /* Note: we gave away ownership of the event at this point */
5141 GST_LOG_OBJECT (pad, "sent event to peerpad %" GST_PTR_FORMAT ", result %d",
5143 gst_object_unref (peerpad);
5147 /* ERROR handling */
5150 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
5151 gst_event_unref (event);
5156 GST_DEBUG_OBJECT (pad, "Dropping event because pad is not linked");
5157 gst_event_unref (event);
5158 GST_OBJECT_UNLOCK (pad);
5163 GST_DEBUG_OBJECT (pad,
5164 "Not forwarding event since we're flushing and blocking");
5165 gst_event_unref (event);
5166 GST_OBJECT_UNLOCK (pad);
5172 * gst_pad_send_event:
5173 * @pad: a #GstPad to send the event to.
5174 * @event: the #GstEvent to send to the pad.
5176 * Sends the event to the pad. This function can be used
5177 * by applications to send events in the pipeline.
5179 * If @pad is a source pad, @event should be an upstream event. If @pad is a
5180 * sink pad, @event should be a downstream event. For example, you would not
5181 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
5182 * Furthermore, some downstream events have to be serialized with data flow,
5183 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
5184 * the event needs to be serialized with data flow, this function will take the
5185 * pad's stream lock while calling its event function.
5187 * To find out whether an event type is upstream, downstream, or downstream and
5188 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
5189 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
5190 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or
5191 * plugin doesn't need to bother itself with this information; the core handles
5192 * all necessary locks and checks.
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.
5200 gst_pad_send_event (GstPad * pad, GstEvent * event)
5202 gboolean result = FALSE;
5203 GstPadEventFunction eventfunc;
5204 gboolean serialized, need_unlock = FALSE;
5206 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5207 g_return_val_if_fail (event != NULL, FALSE);
5209 GST_OBJECT_LOCK (pad);
5210 if (GST_PAD_IS_SINK (pad)) {
5211 if (G_UNLIKELY (!GST_EVENT_IS_DOWNSTREAM (event)))
5212 goto wrong_direction;
5213 serialized = GST_EVENT_IS_SERIALIZED (event);
5214 } else if (GST_PAD_IS_SRC (pad)) {
5215 if (G_UNLIKELY (!GST_EVENT_IS_UPSTREAM (event)))
5216 goto wrong_direction;
5217 /* events on srcpad never are serialized */
5220 goto unknown_direction;
5222 if (G_UNLIKELY (GST_EVENT_SRC (event) == NULL)) {
5223 GST_LOG_OBJECT (pad, "event had no source, setting pad as event source");
5224 GST_EVENT_SRC (event) = gst_object_ref (pad);
5228 if (G_UNLIKELY (GST_PAD_DO_EVENT_SIGNALS (pad) > 0)) {
5229 GST_OBJECT_UNLOCK (pad);
5231 if (!gst_pad_emit_have_data_signal (pad, GST_MINI_OBJECT_CAST (event)))
5234 GST_OBJECT_LOCK (pad);
5237 switch (GST_EVENT_TYPE (event)) {
5238 case GST_EVENT_FLUSH_START:
5239 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad,
5240 "have event type %d (FLUSH_START)", GST_EVENT_TYPE (event));
5242 /* can't even accept a flush begin event when flushing */
5243 if (GST_PAD_IS_FLUSHING (pad))
5246 pad_invalidate_cache (pad);
5247 GST_PAD_SET_FLUSHING (pad);
5248 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "set flush flag");
5250 case GST_EVENT_FLUSH_STOP:
5251 if (G_LIKELY (GST_PAD_ACTIVATE_MODE (pad) != GST_ACTIVATE_NONE)) {
5252 GST_PAD_UNSET_FLUSHING (pad);
5253 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "cleared flush flag");
5255 GST_OBJECT_UNLOCK (pad);
5256 /* grab stream lock */
5257 GST_PAD_STREAM_LOCK (pad);
5259 GST_OBJECT_LOCK (pad);
5262 GST_CAT_DEBUG_OBJECT (GST_CAT_EVENT, pad, "have event type %s",
5263 GST_EVENT_TYPE_NAME (event));
5265 /* make this a little faster, no point in grabbing the lock
5266 * if the pad is allready flushing. */
5267 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
5271 /* lock order: STREAM_LOCK, LOCK, recheck flushing. */
5272 GST_OBJECT_UNLOCK (pad);
5273 GST_PAD_STREAM_LOCK (pad);
5275 GST_OBJECT_LOCK (pad);
5276 if (G_UNLIKELY (GST_PAD_IS_FLUSHING (pad)))
5281 if (G_UNLIKELY ((eventfunc = GST_PAD_EVENTFUNC (pad)) == NULL))
5284 GST_OBJECT_UNLOCK (pad);
5286 result = eventfunc (pad, event);
5289 GST_PAD_STREAM_UNLOCK (pad);
5291 GST_DEBUG_OBJECT (pad, "sent event, result %d", result);
5295 /* ERROR handling */
5298 g_warning ("pad %s:%s sending %s event in wrong direction",
5299 GST_DEBUG_PAD_NAME (pad), GST_EVENT_TYPE_NAME (event));
5300 GST_OBJECT_UNLOCK (pad);
5301 gst_event_unref (event);
5306 g_warning ("pad %s:%s has invalid direction", GST_DEBUG_PAD_NAME (pad));
5307 GST_OBJECT_UNLOCK (pad);
5308 gst_event_unref (event);
5313 g_warning ("pad %s:%s has no event handler, file a bug.",
5314 GST_DEBUG_PAD_NAME (pad));
5315 GST_OBJECT_UNLOCK (pad);
5317 GST_PAD_STREAM_UNLOCK (pad);
5318 gst_event_unref (event);
5323 GST_OBJECT_UNLOCK (pad);
5325 GST_PAD_STREAM_UNLOCK (pad);
5326 GST_CAT_INFO_OBJECT (GST_CAT_EVENT, pad,
5327 "Received event on flushing pad. Discarding");
5328 gst_event_unref (event);
5333 GST_DEBUG_OBJECT (pad, "Dropping event after FALSE probe return");
5334 gst_event_unref (event);
5340 * gst_pad_set_element_private:
5341 * @pad: the #GstPad to set the private data of.
5342 * @priv: The private data to attach to the pad.
5344 * Set the given private data gpointer on the pad.
5345 * This function can only be used by the element that owns the pad.
5346 * No locking is performed in this function.
5349 gst_pad_set_element_private (GstPad * pad, gpointer priv)
5351 pad->element_private = priv;
5355 * gst_pad_get_element_private:
5356 * @pad: the #GstPad to get the private data of.
5358 * Gets the private data of a pad.
5359 * No locking is performed in this function.
5361 * Returns: a #gpointer to the private data.
5364 gst_pad_get_element_private (GstPad * pad)
5366 return pad->element_private;
5370 do_stream_status (GstPad * pad, GstStreamStatusType type,
5371 GThread * thread, GstTask * task)
5375 GST_DEBUG_OBJECT (pad, "doing stream-status %d", type);
5377 if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (pad)))) {
5378 if (GST_IS_ELEMENT (parent)) {
5379 GstMessage *message;
5380 GValue value = { 0 };
5382 if (type == GST_STREAM_STATUS_TYPE_ENTER) {
5383 gchar *tname, *ename, *pname;
5385 /* create a good task name */
5386 ename = gst_element_get_name (parent);
5387 pname = gst_pad_get_name (pad);
5388 tname = g_strdup_printf ("%s:%s", ename, pname);
5392 gst_object_set_name (GST_OBJECT_CAST (task), tname);
5396 message = gst_message_new_stream_status (GST_OBJECT_CAST (pad),
5399 g_value_init (&value, GST_TYPE_TASK);
5400 g_value_set_object (&value, task);
5401 gst_message_set_stream_status_object (message, &value);
5402 g_value_unset (&value);
5404 GST_DEBUG_OBJECT (pad, "posting stream-status %d", type);
5405 gst_element_post_message (parent, message);
5407 gst_object_unref (parent);
5412 pad_enter_thread (GstTask * task, GThread * thread, gpointer user_data)
5414 do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_ENTER,
5419 pad_leave_thread (GstTask * task, GThread * thread, gpointer user_data)
5421 do_stream_status (GST_PAD_CAST (user_data), GST_STREAM_STATUS_TYPE_LEAVE,
5425 static GstTaskThreadCallbacks thr_callbacks = {
5431 * gst_pad_start_task:
5432 * @pad: the #GstPad to start the task of
5433 * @func: the task function to call
5434 * @data: data passed to the task function
5436 * Starts a task that repeatedly calls @func with @data. This function
5437 * is mostly used in pad activation functions to start the dataflow.
5438 * The #GST_PAD_STREAM_LOCK of @pad will automatically be acquired
5439 * before @func is called.
5441 * Returns: a %TRUE if the task could be started.
5444 gst_pad_start_task (GstPad * pad, GstTaskFunction func, gpointer data)
5449 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5450 g_return_val_if_fail (func != NULL, FALSE);
5452 GST_DEBUG_OBJECT (pad, "start task");
5454 GST_OBJECT_LOCK (pad);
5455 task = GST_PAD_TASK (pad);
5457 task = gst_task_create (func, data);
5458 gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
5459 gst_task_set_thread_callbacks (task, &thr_callbacks, pad, NULL);
5460 GST_DEBUG_OBJECT (pad, "created task");
5461 GST_PAD_TASK (pad) = task;
5462 gst_object_ref (task);
5463 /* release lock to post the message */
5464 GST_OBJECT_UNLOCK (pad);
5466 do_stream_status (pad, GST_STREAM_STATUS_TYPE_CREATE, NULL, task);
5468 gst_object_unref (task);
5470 GST_OBJECT_LOCK (pad);
5471 /* nobody else is supposed to have changed the pad now */
5472 if (GST_PAD_TASK (pad) != task)
5473 goto concurrent_stop;
5475 res = gst_task_set_state (task, GST_TASK_STARTED);
5476 GST_OBJECT_UNLOCK (pad);
5483 GST_OBJECT_UNLOCK (pad);
5489 * gst_pad_pause_task:
5490 * @pad: the #GstPad to pause the task of
5492 * Pause the task of @pad. This function will also wait until the
5493 * function executed by the task is finished if this function is not
5494 * called from the task function.
5496 * Returns: a TRUE if the task could be paused or FALSE when the pad
5500 gst_pad_pause_task (GstPad * pad)
5505 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5507 GST_DEBUG_OBJECT (pad, "pause task");
5509 GST_OBJECT_LOCK (pad);
5510 task = GST_PAD_TASK (pad);
5513 res = gst_task_set_state (task, GST_TASK_PAUSED);
5514 GST_OBJECT_UNLOCK (pad);
5516 /* wait for task function to finish, this lock is recursive so it does nothing
5517 * when the pause is called from the task itself */
5518 GST_PAD_STREAM_LOCK (pad);
5519 GST_PAD_STREAM_UNLOCK (pad);
5525 GST_DEBUG_OBJECT (pad, "pad has no task");
5526 GST_OBJECT_UNLOCK (pad);
5532 * gst_pad_stop_task:
5533 * @pad: the #GstPad to stop the task of
5535 * Stop the task of @pad. This function will also make sure that the
5536 * function executed by the task will effectively stop if not called
5537 * from the GstTaskFunction.
5539 * This function will deadlock if called from the GstTaskFunction of
5540 * the task. Use gst_task_pause() instead.
5542 * Regardless of whether the pad has a task, the stream lock is acquired and
5543 * released so as to ensure that streaming through this pad has finished.
5545 * Returns: a TRUE if the task could be stopped or FALSE on error.
5548 gst_pad_stop_task (GstPad * pad)
5553 g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
5555 GST_DEBUG_OBJECT (pad, "stop task");
5557 GST_OBJECT_LOCK (pad);
5558 task = GST_PAD_TASK (pad);
5561 GST_PAD_TASK (pad) = NULL;
5562 res = gst_task_set_state (task, GST_TASK_STOPPED);
5563 GST_OBJECT_UNLOCK (pad);
5565 GST_PAD_STREAM_LOCK (pad);
5566 GST_PAD_STREAM_UNLOCK (pad);
5568 if (!gst_task_join (task))
5571 gst_object_unref (task);
5577 GST_DEBUG_OBJECT (pad, "no task");
5578 GST_OBJECT_UNLOCK (pad);
5580 GST_PAD_STREAM_LOCK (pad);
5581 GST_PAD_STREAM_UNLOCK (pad);
5583 /* this is not an error */
5588 /* this is bad, possibly the application tried to join the task from
5589 * the task's thread. We install the task again so that it will be stopped
5590 * again from the right thread next time hopefully. */
5591 GST_OBJECT_LOCK (pad);
5592 GST_DEBUG_OBJECT (pad, "join failed");
5593 /* we can only install this task if there was no other task */
5594 if (GST_PAD_TASK (pad) == NULL)
5595 GST_PAD_TASK (pad) = task;
5596 GST_OBJECT_UNLOCK (pad);