2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wim.taymans@chello.be>
5 * gstpad.h: Header for GstPad object
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., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
27 #include <gst/gstconfig.h>
29 typedef struct _GstPad GstPad;
30 typedef struct _GstPadPrivate GstPadPrivate;
31 typedef struct _GstPadClass GstPadClass;
32 typedef struct _GstPadProbeInfo GstPadProbeInfo;
36 * @GST_PAD_UNKNOWN: direction is unknown.
37 * @GST_PAD_SRC: the pad is a source pad.
38 * @GST_PAD_SINK: the pad is a sink pad.
40 * The direction of a pad.
50 * @GST_PAD_MODE_NONE: Pad will not handle dataflow
51 * @GST_PAD_MODE_PUSH: Pad handles dataflow in downstream push mode
52 * @GST_PAD_MODE_PULL: Pad handles dataflow in upstream pull mode
54 * The status of a GstPad. After activating a pad, which usually happens when the
55 * parent element goes from READY to PAUSED, the GstPadMode defines if the
56 * pad operates in push or pull mode.
64 const gchar * gst_pad_mode_get_name (GstPadMode mode);
66 #include <gst/gstobject.h>
67 #include <gst/gstbuffer.h>
68 #include <gst/gstbufferlist.h>
69 #include <gst/gstcaps.h>
70 #include <gst/gstpadtemplate.h>
71 #include <gst/gstevent.h>
72 #include <gst/gstquery.h>
73 #include <gst/gsttask.h>
80 #define GST_TYPE_PAD (gst_pad_get_type ())
81 #define GST_IS_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_PAD))
82 #define GST_IS_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_PAD))
83 #define GST_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_PAD, GstPad))
84 #define GST_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_PAD, GstPadClass))
85 #define GST_PAD_CAST(obj) ((GstPad*)(obj))
91 * @GST_PAD_LINK_OK : link succeeded
92 * @GST_PAD_LINK_WRONG_HIERARCHY: pads have no common grandparent
93 * @GST_PAD_LINK_WAS_LINKED : pad was already linked
94 * @GST_PAD_LINK_WRONG_DIRECTION: pads have wrong direction
95 * @GST_PAD_LINK_NOFORMAT : pads do not have common format
96 * @GST_PAD_LINK_NOSCHED : pads cannot cooperate in scheduling
97 * @GST_PAD_LINK_REFUSED : refused for some reason
99 * Result values from gst_pad_link and friends.
103 GST_PAD_LINK_WRONG_HIERARCHY = -1,
104 GST_PAD_LINK_WAS_LINKED = -2,
105 GST_PAD_LINK_WRONG_DIRECTION = -3,
106 GST_PAD_LINK_NOFORMAT = -4,
107 GST_PAD_LINK_NOSCHED = -5,
108 GST_PAD_LINK_REFUSED = -6
112 * GST_PAD_LINK_FAILED:
113 * @ret: the #GstPadLinkReturn value
115 * Macro to test if the given #GstPadLinkReturn value indicates a failed
118 #define GST_PAD_LINK_FAILED(ret) ((ret) < GST_PAD_LINK_OK)
121 * GST_PAD_LINK_SUCCESSFUL:
122 * @ret: the #GstPadLinkReturn value
124 * Macro to test if the given #GstPadLinkReturn value indicates a successful
127 #define GST_PAD_LINK_SUCCESSFUL(ret) ((ret) >= GST_PAD_LINK_OK)
131 * @GST_FLOW_OK: Data passing was ok.
132 * @GST_FLOW_NOT_LINKED: Pad is not linked.
133 * @GST_FLOW_FLUSHING: Pad is flushing.
134 * @GST_FLOW_EOS: Pad is EOS.
135 * @GST_FLOW_NOT_NEGOTIATED: Pad is not negotiated.
136 * @GST_FLOW_ERROR: Some (fatal) error occured. Element generating
137 * this error should post an error message with more
139 * @GST_FLOW_NOT_SUPPORTED: This operation is not supported.
140 * @GST_FLOW_CUSTOM_SUCCESS: Elements can use values starting from
141 * this (and higher) to define custom success
143 * @GST_FLOW_CUSTOM_SUCCESS_1: Pre-defined custom success code (define your
144 * custom success code to this to avoid compiler
146 * @GST_FLOW_CUSTOM_SUCCESS_2: Pre-defined custom success code.
147 * @GST_FLOW_CUSTOM_ERROR: Elements can use values starting from
148 * this (and lower) to define custom error codes.
149 * @GST_FLOW_CUSTOM_ERROR_1: Pre-defined custom error code (define your
150 * custom error code to this to avoid compiler
152 * @GST_FLOW_CUSTOM_ERROR_2: Pre-defined custom error code.
154 * The result of passing data to a pad.
156 * Note that the custom return values should not be exposed outside of the
160 /* custom success starts here */
161 GST_FLOW_CUSTOM_SUCCESS_2 = 102,
162 GST_FLOW_CUSTOM_SUCCESS_1 = 101,
163 GST_FLOW_CUSTOM_SUCCESS = 100,
165 /* core predefined */
167 /* expected failures */
168 GST_FLOW_NOT_LINKED = -1,
169 GST_FLOW_FLUSHING = -2,
172 GST_FLOW_NOT_NEGOTIATED = -4,
174 GST_FLOW_NOT_SUPPORTED = -6,
176 /* custom error starts here */
177 GST_FLOW_CUSTOM_ERROR = -100,
178 GST_FLOW_CUSTOM_ERROR_1 = -101,
179 GST_FLOW_CUSTOM_ERROR_2 = -102
182 const gchar* gst_flow_get_name (GstFlowReturn ret);
183 GQuark gst_flow_to_quark (GstFlowReturn ret);
187 * @GST_PAD_LINK_CHECK_NOTHING: Don't check hierarchy or caps compatibility.
188 * @GST_PAD_LINK_CHECK_HIERARCHY: Check the pads have same parents/grandparents.
189 * Could be omitted if it is already known that the two elements that own the
190 * pads are in the same bin.
191 * @GST_PAD_LINK_CHECK_TEMPLATE_CAPS: Check if the pads are compatible by using
192 * their template caps. This is much faster than @GST_PAD_LINK_CHECK_CAPS, but
193 * would be unsafe e.g. if one pad has %GST_CAPS_ANY.
194 * @GST_PAD_LINK_CHECK_CAPS: Check if the pads are compatible by comparing the
195 * caps returned by gst_pad_query_caps().
196 * @GST_PAD_LINK_CHECK_DEFAULT: The default checks done when linking
197 * pads (i.e. the ones used by gst_pad_link()).
199 * The amount of checking to be done when linking pads. @GST_PAD_LINK_CHECK_CAPS
200 * and @GST_PAD_LINK_CHECK_TEMPLATE_CAPS are mutually exclusive. If both are
201 * specified, expensive but safe @GST_PAD_LINK_CHECK_CAPS are performed.
204 * Only disable some of the checks if you are 100% certain you know the link
205 * will not fail because of hierarchy/caps compatibility failures. If uncertain,
206 * use the default checks (%GST_PAD_LINK_CHECK_DEFAULT) or the regular methods
207 * for linking the pads.
212 GST_PAD_LINK_CHECK_NOTHING = 0,
213 GST_PAD_LINK_CHECK_HIERARCHY = 1 << 0,
214 GST_PAD_LINK_CHECK_TEMPLATE_CAPS = 1 << 1,
215 GST_PAD_LINK_CHECK_CAPS = 1 << 2,
217 GST_PAD_LINK_CHECK_DEFAULT = GST_PAD_LINK_CHECK_HIERARCHY | GST_PAD_LINK_CHECK_CAPS
222 * GstPadActivateFunction:
224 * @parent: the parent of @pad
226 * This function is called when the pad is activated during the element
227 * READY to PAUSED state change. By default this function will call the
228 * activate function that puts the pad in push mode but elements can
229 * override this function to activate the pad in pull mode if they wish.
231 * Returns: TRUE if the pad could be activated.
233 typedef gboolean (*GstPadActivateFunction) (GstPad *pad, GstObject *parent);
235 * GstPadActivateModeFunction:
237 * @parent: the parent of @pad
238 * @mode: the requested activation mode of @pad
239 * @active: activate or deactivate the pad.
241 * The prototype of the push and pull activate functions.
243 * Returns: TRUE if the pad could be activated or deactivated.
245 typedef gboolean (*GstPadActivateModeFunction) (GstPad *pad, GstObject *parent,
246 GstPadMode mode, gboolean active);
251 * GstPadChainFunction:
252 * @pad: the sink #GstPad that performed the chain.
253 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
254 * @parent is guaranteed to be not-NULL and remain valid during the
255 * execution of this function.
256 * @buffer: the #GstBuffer that is chained, not %NULL.
258 * A function that will be called on sinkpads when chaining buffers.
259 * The function typically processes the data contained in the buffer and
260 * either consumes the data or passes it on to the internally linked pad(s).
262 * The implementer of this function receives a refcount to @buffer and should
263 * gst_buffer_unref() when the buffer is no longer needed.
265 * When a chain function detects an error in the data stream, it must post an
266 * error on the bus and return an appropriate #GstFlowReturn value.
268 * Returns: #GST_FLOW_OK for success
270 typedef GstFlowReturn (*GstPadChainFunction) (GstPad *pad, GstObject *parent,
274 * GstPadChainListFunction:
275 * @pad: the sink #GstPad that performed the chain.
276 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
277 * @parent is guaranteed to be not-NULL and remain valid during the
278 * execution of this function.
279 * @list: the #GstBufferList that is chained, not %NULL.
281 * A function that will be called on sinkpads when chaining buffer lists.
282 * The function typically processes the data contained in the buffer list and
283 * either consumes the data or passes it on to the internally linked pad(s).
285 * The implementer of this function receives a refcount to @list and
286 * should gst_buffer_list_unref() when the list is no longer needed.
288 * When a chainlist function detects an error in the data stream, it must
289 * post an error on the bus and return an appropriate #GstFlowReturn value.
291 * Returns: #GST_FLOW_OK for success
293 typedef GstFlowReturn (*GstPadChainListFunction) (GstPad *pad, GstObject *parent,
294 GstBufferList *list);
297 * GstPadGetRangeFunction:
298 * @pad: the src #GstPad to perform the getrange on.
299 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
300 * @parent is guaranteed to be not-NULL and remain valid during the
301 * execution of this function.
302 * @offset: the offset of the range
303 * @length: the length of the range
304 * @buffer: a memory location to hold the result buffer, cannot be NULL.
306 * This function will be called on source pads when a peer element
307 * request a buffer at the specified @offset and @length. If this function
308 * returns #GST_FLOW_OK, the result buffer will be stored in @buffer. The
309 * contents of @buffer is invalid for any other return value.
311 * This function is installed on a source pad with
312 * gst_pad_set_getrange_function() and can only be called on source pads after
313 * they are successfully activated with gst_pad_activate_mode() with the
314 * #GST_PAD_MODE_PULL.
316 * @offset and @length are always given in byte units. @offset must normally be a value
317 * between 0 and the length in bytes of the data available on @pad. The
318 * length (duration in bytes) can be retrieved with a #GST_QUERY_DURATION or with a
319 * #GST_QUERY_SEEKING.
321 * Any @offset larger or equal than the length will make the function return
322 * #GST_FLOW_EOS, which corresponds to EOS. In this case @buffer does not
323 * contain a valid buffer.
325 * The buffer size of @buffer will only be smaller than @length when @offset is
326 * near the end of the stream. In all other cases, the size of @buffer must be
327 * exactly the requested size.
329 * It is allowed to call this function with a 0 @length and valid @offset, in
330 * which case @buffer will contain a 0-sized buffer and the function returns
333 * When this function is called with a -1 @offset, the sequentially next buffer
334 * of length @length in the stream is returned.
336 * When this function is called with a -1 @length, a buffer with a default
337 * optimal length is returned in @buffer. The length might depend on the value
340 * Returns: #GST_FLOW_OK for success and a valid buffer in @buffer. Any other
341 * return value leaves @buffer undefined.
343 typedef GstFlowReturn (*GstPadGetRangeFunction) (GstPad *pad, GstObject *parent,
344 guint64 offset, guint length,
348 * GstPadEventFunction:
349 * @pad: the #GstPad to handle the event.
350 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
351 * @parent is guaranteed to be not-NULL and remain valid during the
352 * execution of this function.
353 * @event: the #GstEvent to handle.
355 * Function signature to handle an event for the pad.
357 * Returns: TRUE if the pad could handle the event.
359 typedef gboolean (*GstPadEventFunction) (GstPad *pad, GstObject *parent,
365 * GstPadIterIntLinkFunction:
366 * @pad: The #GstPad to query.
367 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
368 * @parent is guaranteed to be not-NULL and remain valid during the
369 * execution of this function.
371 * The signature of the internal pad link iterator function.
373 * Returns: a new #GstIterator that will iterate over all pads that are
374 * linked to the given pad on the inside of the parent element.
376 * the caller must call gst_iterator_free() after usage.
378 typedef GstIterator* (*GstPadIterIntLinkFunction) (GstPad *pad, GstObject *parent);
380 /* generic query function */
382 * GstPadQueryFunction:
383 * @pad: the #GstPad to query.
384 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
385 * @parent is guaranteed to be not-NULL and remain valid during the
386 * execution of this function.
387 * @query: the #GstQuery object to execute
389 * The signature of the query function.
391 * Returns: TRUE if the query could be performed.
393 typedef gboolean (*GstPadQueryFunction) (GstPad *pad, GstObject *parent,
399 * GstPadLinkFunction:
400 * @pad: the #GstPad that is linked.
401 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
402 * @parent is guaranteed to be not-NULL and remain valid during the
403 * execution of this function.
404 * @peer: the peer #GstPad of the link
406 * Function signature to handle a new link on the pad.
408 * Returns: the result of the link with the specified peer.
410 typedef GstPadLinkReturn (*GstPadLinkFunction) (GstPad *pad, GstObject *parent, GstPad *peer);
412 * GstPadUnlinkFunction:
413 * @pad: the #GstPad that is linked.
414 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
415 * @parent is guaranteed to be not-NULL and remain valid during the
416 * execution of this function.
418 * Function signature to handle a unlinking the pad prom its peer.
420 typedef void (*GstPadUnlinkFunction) (GstPad *pad, GstObject *parent);
425 * GstPadForwardFunction:
426 * @pad: the #GstPad that is forwarded.
427 * @user_data: the gpointer to optional user data.
429 * A forward function is called for all internally linked pads, see
432 * Returns: TRUE if the dispatching procedure has to be stopped.
434 typedef gboolean (*GstPadForwardFunction) (GstPad *pad, gpointer user_data);
438 * @GST_PAD_PROBE_TYPE_INVALID: invalid probe type
439 * @GST_PAD_PROBE_TYPE_IDLE: probe idle pads and block
440 * @GST_PAD_PROBE_TYPE_BLOCK: probe and block pads
441 * @GST_PAD_PROBE_TYPE_BUFFER: probe buffers
442 * @GST_PAD_PROBE_TYPE_BUFFER_LIST: probe buffer lists
443 * @GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM: probe downstream events
444 * @GST_PAD_PROBE_TYPE_EVENT_UPSTREAM: probe upstream events
445 * @GST_PAD_PROBE_TYPE_EVENT_FLUSH: probe flush events. This probe has to be
446 * explicitly enabled and is not included in the
447 * @@GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM or
448 * @@GST_PAD_PROBE_TYPE_EVENT_UPSTREAM probe types.
449 * @GST_PAD_PROBE_TYPE_QUERY_DOWNSTREAM: probe downstream queries
450 * @GST_PAD_PROBE_TYPE_QUERY_UPSTREAM: probe upstream queries
451 * @GST_PAD_PROBE_TYPE_PUSH: probe push
452 * @GST_PAD_PROBE_TYPE_PULL: probe pull
453 * @GST_PAD_PROBE_TYPE_BLOCKING: probe and block at the next opportunity, at data flow or when idle
454 * @GST_PAD_PROBE_TYPE_DATA_DOWNSTREAM: probe downstream data (buffers, buffer lists, and events)
455 * @GST_PAD_PROBE_TYPE_DATA_UPSTREAM: probe upstream data (events)
456 * @GST_PAD_PROBE_TYPE_DATA_BOTH: probe upstream and downstream data (buffers, buffer lists, and events)
457 * @GST_PAD_PROBE_TYPE_BLOCK_DOWNSTREAM: probe and block downstream data (buffers, buffer lists, and events)
458 * @GST_PAD_PROBE_TYPE_BLOCK_UPSTREAM: probe and block upstream data (events)
459 * @GST_PAD_PROBE_TYPE_EVENT_BOTH: probe upstream and downstream events
460 * @GST_PAD_PROBE_TYPE_QUERY_BOTH: probe upstream and downstream queries
461 * @GST_PAD_PROBE_TYPE_ALL_BOTH: probe upstream events and queries and downstream buffers, buffer lists, events and queries
462 * @GST_PAD_PROBE_TYPE_SCHEDULING: probe push and pull
464 * The different probing types that can occur. When either one of
465 * @GST_PAD_PROBE_TYPE_IDLE or @GST_PAD_PROBE_TYPE_BLOCK is used, the probe will be a
470 GST_PAD_PROBE_TYPE_INVALID = 0,
471 /* flags to control blocking */
472 GST_PAD_PROBE_TYPE_IDLE = (1 << 0),
473 GST_PAD_PROBE_TYPE_BLOCK = (1 << 1),
474 /* flags to select datatypes */
475 GST_PAD_PROBE_TYPE_BUFFER = (1 << 4),
476 GST_PAD_PROBE_TYPE_BUFFER_LIST = (1 << 5),
477 GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM = (1 << 6),
478 GST_PAD_PROBE_TYPE_EVENT_UPSTREAM = (1 << 7),
479 GST_PAD_PROBE_TYPE_EVENT_FLUSH = (1 << 8),
480 GST_PAD_PROBE_TYPE_QUERY_DOWNSTREAM = (1 << 9),
481 GST_PAD_PROBE_TYPE_QUERY_UPSTREAM = (1 << 10),
482 /* flags to select scheduling mode */
483 GST_PAD_PROBE_TYPE_PUSH = (1 << 12),
484 GST_PAD_PROBE_TYPE_PULL = (1 << 13),
486 /* flag combinations */
487 GST_PAD_PROBE_TYPE_BLOCKING = GST_PAD_PROBE_TYPE_IDLE | GST_PAD_PROBE_TYPE_BLOCK,
488 GST_PAD_PROBE_TYPE_DATA_DOWNSTREAM = GST_PAD_PROBE_TYPE_BUFFER | GST_PAD_PROBE_TYPE_BUFFER_LIST | GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM,
489 GST_PAD_PROBE_TYPE_DATA_UPSTREAM = GST_PAD_PROBE_TYPE_EVENT_UPSTREAM,
490 GST_PAD_PROBE_TYPE_DATA_BOTH = GST_PAD_PROBE_TYPE_DATA_DOWNSTREAM | GST_PAD_PROBE_TYPE_DATA_UPSTREAM,
491 GST_PAD_PROBE_TYPE_BLOCK_DOWNSTREAM = GST_PAD_PROBE_TYPE_BLOCK | GST_PAD_PROBE_TYPE_DATA_DOWNSTREAM,
492 GST_PAD_PROBE_TYPE_BLOCK_UPSTREAM = GST_PAD_PROBE_TYPE_BLOCK | GST_PAD_PROBE_TYPE_DATA_UPSTREAM,
493 GST_PAD_PROBE_TYPE_EVENT_BOTH = GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM | GST_PAD_PROBE_TYPE_EVENT_UPSTREAM,
494 GST_PAD_PROBE_TYPE_QUERY_BOTH = GST_PAD_PROBE_TYPE_QUERY_DOWNSTREAM | GST_PAD_PROBE_TYPE_QUERY_UPSTREAM,
495 GST_PAD_PROBE_TYPE_ALL_BOTH = GST_PAD_PROBE_TYPE_DATA_BOTH | GST_PAD_PROBE_TYPE_QUERY_BOTH,
496 GST_PAD_PROBE_TYPE_SCHEDULING = GST_PAD_PROBE_TYPE_PUSH | GST_PAD_PROBE_TYPE_PULL
502 * @GST_PAD_PROBE_OK: normal probe return value
503 * @GST_PAD_PROBE_DROP: drop data in data probes. For push mode this means that
504 * the data item is not sent downstream. For pull mode, it means that the
505 * data item is not passed upstream. In both cases, this result code
506 * returns #GST_FLOW_OK or %TRUE to the caller.
507 * @GST_PAD_PROBE_REMOVE: remove probe
508 * @GST_PAD_PROBE_PASS: pass the data item in the block probe and block on
511 * Different return values for the #GstPadProbeCallback.
517 GST_PAD_PROBE_REMOVE,
524 * @type: the current probe type
525 * @id: the id of the probe
526 * @data: type specific data, check the @type field to know the datatype.
527 * This field can be NULL.
528 * @offset: offset of pull probe, this field is valid when @type contains
529 * #GST_PAD_PROBE_TYPE_PULL
530 * @size: size of pull probe, this field is valid when @type contains
531 * #GST_PAD_PROBE_TYPE_PULL
533 * Info passed in the #GstPadProbeCallback.
535 struct _GstPadProbeInfo
537 GstPadProbeType type;
544 gpointer _gst_reserved[GST_PADDING];
547 #define GST_PAD_PROBE_INFO_TYPE(d) ((d)->type)
548 #define GST_PAD_PROBE_INFO_ID(d) ((d)->id)
549 #define GST_PAD_PROBE_INFO_DATA(d) ((d)->data)
551 #define GST_PAD_PROBE_INFO_BUFFER(d) GST_BUFFER_CAST(GST_PAD_PROBE_INFO_DATA(d))
552 #define GST_PAD_PROBE_INFO_BUFFER_LIST(d) GST_BUFFER_LIST_CAST(GST_PAD_PROBE_INFO_DATA(d))
553 #define GST_PAD_PROBE_INFO_EVENT(d) GST_EVENT_CAST(GST_PAD_PROBE_INFO_DATA(d))
554 #define GST_PAD_PROBE_INFO_QUERY(d) GST_QUERY_CAST(GST_PAD_PROBE_INFO_DATA(d))
556 #define GST_PAD_PROBE_INFO_OFFSET(d) ((d)->offset)
557 #define GST_PAD_PROBE_INFO_SIZE(d) ((d)->size)
559 GstEvent* gst_pad_probe_info_get_event (GstPadProbeInfo * info);
560 GstQuery* gst_pad_probe_info_get_query (GstPadProbeInfo * info);
561 GstBuffer* gst_pad_probe_info_get_buffer (GstPadProbeInfo * info);
562 GstBufferList* gst_pad_probe_info_get_buffer_list (GstPadProbeInfo * info);
565 * GstPadProbeCallback:
566 * @pad: the #GstPad that is blocked
567 * @info: #GstPadProbeInfo
568 * @user_data: the gpointer to optional user data.
570 * Callback used by gst_pad_add_probe(). Gets called to notify about the current
573 * The callback is allowed to modify the data pointer in @info.
575 * Returns: a #GstPadProbeReturn
577 typedef GstPadProbeReturn (*GstPadProbeCallback) (GstPad *pad, GstPadProbeInfo *info,
581 * GstPadStickyEventsForeachFunction:
583 * @event: a sticky #GstEvent.
584 * @user_data: the #gpointer to optional user data.
586 * Callback used by gst_pad_sticky_events_foreach().
588 * When this function returns %TRUE, the next event will be
589 * returned. When %FALSE is returned, gst_pad_sticky_events_foreach() will return.
591 * When @event is set to NULL, the item will be removed from the list of sticky events.
592 * @event can be replaced by assigning a new reference to it.
593 * This function is responsible for unreffing the old event when
594 * removing or modifying.
596 * Returns: %TRUE if the iteration should continue
598 typedef gboolean (*GstPadStickyEventsForeachFunction) (GstPad *pad, GstEvent **event,
603 * @GST_PAD_FLAG_BLOCKED: is dataflow on a pad blocked
604 * @GST_PAD_FLAG_FLUSHING: is pad flushing
605 * @GST_PAD_FLAG_EOS: is pad in EOS state
606 * @GST_PAD_FLAG_BLOCKING: is pad currently blocking on a buffer or event
607 * @GST_PAD_FLAG_NEED_PARENT: ensure that there is a parent object before calling
608 * into the pad callbacks.
609 * @GST_PAD_FLAG_NEED_RECONFIGURE: the pad should be reconfigured/renegotiated.
610 * The flag has to be unset manually after
611 * reconfiguration happened.
612 * @GST_PAD_FLAG_PENDING_EVENTS: the pad has pending events
613 * @GST_PAD_FLAG_FIXED_CAPS: the pad is using fixed caps this means that once the
614 * caps are set on the pad, the caps query function only
615 * returns those caps.
616 * @GST_PAD_FLAG_PROXY_CAPS: the default event and query handler will forward
617 * all events and queries to the internally linked pads
618 * instead of discarding them.
619 * @GST_PAD_FLAG_PROXY_ALLOCATION: the default query handler will forward
620 * allocation queries to the internally linked pads
621 * instead of discarding them.
622 * @GST_PAD_FLAG_PROXY_SCHEDULING: the default query handler will forward
623 * scheduling queries to the internally linked pads
624 * instead of discarding them.
625 * @GST_PAD_FLAG_LAST: offset to define more flags
630 GST_PAD_FLAG_BLOCKED = (GST_OBJECT_FLAG_LAST << 0),
631 GST_PAD_FLAG_FLUSHING = (GST_OBJECT_FLAG_LAST << 1),
632 GST_PAD_FLAG_EOS = (GST_OBJECT_FLAG_LAST << 2),
633 GST_PAD_FLAG_BLOCKING = (GST_OBJECT_FLAG_LAST << 3),
634 GST_PAD_FLAG_NEED_PARENT = (GST_OBJECT_FLAG_LAST << 4),
635 GST_PAD_FLAG_NEED_RECONFIGURE = (GST_OBJECT_FLAG_LAST << 5),
636 GST_PAD_FLAG_PENDING_EVENTS = (GST_OBJECT_FLAG_LAST << 6),
637 GST_PAD_FLAG_FIXED_CAPS = (GST_OBJECT_FLAG_LAST << 7),
638 GST_PAD_FLAG_PROXY_CAPS = (GST_OBJECT_FLAG_LAST << 8),
639 GST_PAD_FLAG_PROXY_ALLOCATION = (GST_OBJECT_FLAG_LAST << 9),
640 GST_PAD_FLAG_PROXY_SCHEDULING = (GST_OBJECT_FLAG_LAST << 10),
642 GST_PAD_FLAG_LAST = (GST_OBJECT_FLAG_LAST << 16)
647 * @element_private: private data owned by the parent element
648 * @padtemplate: padtemplate for this pad
649 * @direction: the direction of the pad, cannot change after creating
652 * The #GstPad structure. Use the functions to update the variables.
658 gpointer element_private;
660 GstPadTemplate *padtemplate;
662 GstPadDirection direction;
665 /* streaming rec_lock */
666 GRecMutex stream_rec_lock;
669 /* block cond, mutex is from the object */
674 GstPadActivateFunction activatefunc;
675 gpointer activatedata;
676 GDestroyNotify activatenotify;
677 GstPadActivateModeFunction activatemodefunc;
678 gpointer activatemodedata;
679 GDestroyNotify activatemodenotify;
683 GstPadLinkFunction linkfunc;
685 GDestroyNotify linknotify;
686 GstPadUnlinkFunction unlinkfunc;
688 GDestroyNotify unlinknotify;
690 /* data transport functions */
691 GstPadChainFunction chainfunc;
693 GDestroyNotify chainnotify;
694 GstPadChainListFunction chainlistfunc;
695 gpointer chainlistdata;
696 GDestroyNotify chainlistnotify;
697 GstPadGetRangeFunction getrangefunc;
698 gpointer getrangedata;
699 GDestroyNotify getrangenotify;
700 GstPadEventFunction eventfunc;
702 GDestroyNotify eventnotify;
707 /* generic query method */
708 GstPadQueryFunction queryfunc;
710 GDestroyNotify querynotify;
713 GstPadIterIntLinkFunction iterintlinkfunc;
714 gpointer iterintlinkdata;
715 GDestroyNotify iterintlinknotify;
717 /* counts number of probes attached. */
723 gpointer _gst_reserved[GST_PADDING];
726 struct _GstPadClass {
727 GstObjectClass parent_class;
729 /* signal callbacks */
730 void (*linked) (GstPad *pad, GstPad *peer);
731 void (*unlinked) (GstPad *pad, GstPad *peer);
734 gpointer _gst_reserved[GST_PADDING];
738 /***** helper macros *****/
740 #define GST_PAD_NAME(pad) (GST_OBJECT_NAME(pad))
741 #define GST_PAD_PARENT(pad) (GST_ELEMENT_CAST(GST_OBJECT_PARENT(pad)))
742 #define GST_PAD_ELEMENT_PRIVATE(pad) (GST_PAD_CAST(pad)->element_private)
743 #define GST_PAD_PAD_TEMPLATE(pad) (GST_PAD_CAST(pad)->padtemplate)
744 #define GST_PAD_DIRECTION(pad) (GST_PAD_CAST(pad)->direction)
745 #define GST_PAD_TASK(pad) (GST_PAD_CAST(pad)->task)
746 #define GST_PAD_MODE(pad) (GST_PAD_CAST(pad)->mode)
748 #define GST_PAD_ACTIVATEFUNC(pad) (GST_PAD_CAST(pad)->activatefunc)
749 #define GST_PAD_ACTIVATEMODEFUNC(pad) (GST_PAD_CAST(pad)->activatemodefunc)
750 #define GST_PAD_CHAINFUNC(pad) (GST_PAD_CAST(pad)->chainfunc)
751 #define GST_PAD_CHAINLISTFUNC(pad) (GST_PAD_CAST(pad)->chainlistfunc)
752 #define GST_PAD_GETRANGEFUNC(pad) (GST_PAD_CAST(pad)->getrangefunc)
753 #define GST_PAD_EVENTFUNC(pad) (GST_PAD_CAST(pad)->eventfunc)
754 #define GST_PAD_QUERYFUNC(pad) (GST_PAD_CAST(pad)->queryfunc)
755 #define GST_PAD_ITERINTLINKFUNC(pad) (GST_PAD_CAST(pad)->iterintlinkfunc)
757 #define GST_PAD_PEER(pad) (GST_PAD_CAST(pad)->peer)
758 #define GST_PAD_LINKFUNC(pad) (GST_PAD_CAST(pad)->linkfunc)
759 #define GST_PAD_UNLINKFUNC(pad) (GST_PAD_CAST(pad)->unlinkfunc)
761 #define GST_PAD_IS_SRC(pad) (GST_PAD_DIRECTION(pad) == GST_PAD_SRC)
762 #define GST_PAD_IS_SINK(pad) (GST_PAD_DIRECTION(pad) == GST_PAD_SINK)
764 #define GST_PAD_IS_LINKED(pad) (GST_PAD_PEER(pad) != NULL)
766 #define GST_PAD_IS_ACTIVE(pad) (GST_PAD_MODE(pad) != GST_PAD_MODE_NONE)
768 #define GST_PAD_IS_BLOCKED(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_BLOCKED))
769 #define GST_PAD_IS_BLOCKING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_BLOCKING))
771 #define GST_PAD_IS_FLUSHING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_FLUSHING))
772 #define GST_PAD_SET_FLUSHING(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_FLUSHING))
773 #define GST_PAD_UNSET_FLUSHING(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_FLUSHING))
775 #define GST_PAD_IS_EOS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_EOS))
777 #define GST_PAD_NEEDS_RECONFIGURE(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_NEED_RECONFIGURE))
778 #define GST_PAD_HAS_PENDING_EVENTS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PENDING_EVENTS))
779 #define GST_PAD_IS_FIXED_CAPS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_FIXED_CAPS))
780 #define GST_PAD_NEEDS_PARENT(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_NEED_PARENT))
782 #define GST_PAD_IS_PROXY_CAPS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PROXY_CAPS))
783 #define GST_PAD_SET_PROXY_CAPS(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_PROXY_CAPS))
784 #define GST_PAD_UNSET_PROXY_CAPS(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_PROXY_CAPS))
786 #define GST_PAD_IS_PROXY_ALLOCATION(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PROXY_ALLOCATION))
787 #define GST_PAD_SET_PROXY_ALLOCATION(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_PROXY_ALLOCATION))
788 #define GST_PAD_UNSET_PROXY_ALLOCATION(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_PROXY_ALLOCATION))
790 #define GST_PAD_IS_PROXY_SCHEDULING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PROXY_SCHEDULING))
791 #define GST_PAD_SET_PROXY_SCHEDULING(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_PROXY_SCHEDULING))
792 #define GST_PAD_UNSET_PROXY_SCHEDULING(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_PROXY_SCHEDULING))
795 * GST_PAD_GET_STREAM_LOCK:
798 * Get the stream lock of @pad. The stream lock is protecting the
799 * resources used in the data processing functions of @pad.
801 #define GST_PAD_GET_STREAM_LOCK(pad) (&(GST_PAD_CAST(pad)->stream_rec_lock))
803 * GST_PAD_STREAM_LOCK:
806 * Lock the stream lock of @pad.
808 #define GST_PAD_STREAM_LOCK(pad) g_rec_mutex_lock(GST_PAD_GET_STREAM_LOCK(pad))
810 * GST_PAD_STREAM_TRYLOCK:
813 * Try to Lock the stream lock of the pad, return TRUE if the lock could be
816 #define GST_PAD_STREAM_TRYLOCK(pad) g_rec_mutex_trylock(GST_PAD_GET_STREAM_LOCK(pad))
818 * GST_PAD_STREAM_UNLOCK:
821 * Unlock the stream lock of @pad.
823 #define GST_PAD_STREAM_UNLOCK(pad) g_rec_mutex_unlock(GST_PAD_GET_STREAM_LOCK(pad))
825 #define GST_PAD_BLOCK_GET_COND(pad) (&GST_PAD_CAST(pad)->block_cond)
826 #define GST_PAD_BLOCK_WAIT(pad) (g_cond_wait(GST_PAD_BLOCK_GET_COND (pad), GST_OBJECT_GET_LOCK (pad)))
827 #define GST_PAD_BLOCK_SIGNAL(pad) (g_cond_signal(GST_PAD_BLOCK_GET_COND (pad)))
828 #define GST_PAD_BLOCK_BROADCAST(pad) (g_cond_broadcast(GST_PAD_BLOCK_GET_COND (pad)))
830 GType gst_pad_get_type (void);
833 GstPad* gst_pad_new (const gchar *name, GstPadDirection direction);
834 GstPad* gst_pad_new_from_template (GstPadTemplate *templ, const gchar *name);
835 GstPad* gst_pad_new_from_static_template (GstStaticPadTemplate *templ, const gchar *name);
840 * @pad: the pad to get the name from
842 * Get a copy of the name of the pad. g_free() after usage.
846 #define gst_pad_get_name(pad) gst_object_get_name (GST_OBJECT_CAST (pad))
848 * gst_pad_get_parent:
849 * @pad: the pad to get the parent of
851 * Get the parent of @pad. This function increases the refcount
852 * of the parent object so you should gst_object_unref() it after usage.
853 * Can return NULL if the pad did not have a parent.
857 #define gst_pad_get_parent(pad) gst_object_get_parent (GST_OBJECT_CAST (pad))
859 GstPadDirection gst_pad_get_direction (GstPad *pad);
861 gboolean gst_pad_set_active (GstPad *pad, gboolean active);
862 gboolean gst_pad_is_active (GstPad *pad);
863 gboolean gst_pad_activate_mode (GstPad *pad, GstPadMode mode,
866 gulong gst_pad_add_probe (GstPad *pad,
867 GstPadProbeType mask,
868 GstPadProbeCallback callback,
870 GDestroyNotify destroy_data);
871 void gst_pad_remove_probe (GstPad *pad, gulong id);
873 gboolean gst_pad_is_blocked (GstPad *pad);
874 gboolean gst_pad_is_blocking (GstPad *pad);
876 void gst_pad_mark_reconfigure (GstPad *pad);
877 gboolean gst_pad_needs_reconfigure (GstPad *pad);
878 gboolean gst_pad_check_reconfigure (GstPad *pad);
880 void gst_pad_set_element_private (GstPad *pad, gpointer priv);
881 gpointer gst_pad_get_element_private (GstPad *pad);
883 GstPadTemplate* gst_pad_get_pad_template (GstPad *pad);
885 GstFlowReturn gst_pad_store_sticky_event (GstPad *pad, GstEvent *event);
886 GstEvent* gst_pad_get_sticky_event (GstPad *pad, GstEventType event_type,
888 void gst_pad_sticky_events_foreach (GstPad *pad, GstPadStickyEventsForeachFunction foreach_func, gpointer user_data);
890 /* data passing setup functions */
891 void gst_pad_set_activate_function_full (GstPad *pad,
892 GstPadActivateFunction activate,
894 GDestroyNotify notify);
895 void gst_pad_set_activatemode_function_full (GstPad *pad,
896 GstPadActivateModeFunction activatemode,
898 GDestroyNotify notify);
899 /* data passing functions */
900 void gst_pad_set_chain_function_full (GstPad *pad,
901 GstPadChainFunction chain,
903 GDestroyNotify notify);
904 void gst_pad_set_chain_list_function_full (GstPad *pad,
905 GstPadChainListFunction chainlist,
907 GDestroyNotify notify);
908 void gst_pad_set_getrange_function_full (GstPad *pad,
909 GstPadGetRangeFunction get,
911 GDestroyNotify notify);
912 void gst_pad_set_event_function_full (GstPad *pad,
913 GstPadEventFunction event,
915 GDestroyNotify notify);
917 #define gst_pad_set_activate_function(p,f) gst_pad_set_activate_function_full((p),(f),NULL,NULL)
918 #define gst_pad_set_activatemode_function(p,f) gst_pad_set_activatemode_function_full((p),(f),NULL,NULL)
919 #define gst_pad_set_chain_function(p,f) gst_pad_set_chain_function_full((p),(f),NULL,NULL)
920 #define gst_pad_set_chain_list_function(p,f) gst_pad_set_chain_list_function_full((p),(f),NULL,NULL)
921 #define gst_pad_set_getrange_function(p,f) gst_pad_set_getrange_function_full((p),(f),NULL,NULL)
922 #define gst_pad_set_event_function(p,f) gst_pad_set_event_function_full((p),(f),NULL,NULL)
925 void gst_pad_set_link_function_full (GstPad *pad,
926 GstPadLinkFunction link,
928 GDestroyNotify notify);
929 void gst_pad_set_unlink_function_full (GstPad *pad,
930 GstPadUnlinkFunction unlink,
932 GDestroyNotify notify);
934 #define gst_pad_set_link_function(p,f) gst_pad_set_link_function_full((p),(f),NULL,NULL)
935 #define gst_pad_set_unlink_function(p,f) gst_pad_set_unlink_function_full((p),(f),NULL,NULL)
937 gboolean gst_pad_can_link (GstPad *srcpad, GstPad *sinkpad);
938 GstPadLinkReturn gst_pad_link (GstPad *srcpad, GstPad *sinkpad);
939 GstPadLinkReturn gst_pad_link_full (GstPad *srcpad, GstPad *sinkpad, GstPadLinkCheck flags);
940 gboolean gst_pad_unlink (GstPad *srcpad, GstPad *sinkpad);
941 gboolean gst_pad_is_linked (GstPad *pad);
943 GstPad* gst_pad_get_peer (GstPad *pad);
945 GstCaps* gst_pad_get_pad_template_caps (GstPad *pad);
947 /* capsnego function for linked/unlinked pads */
948 GstCaps * gst_pad_get_current_caps (GstPad * pad);
949 gboolean gst_pad_has_current_caps (GstPad * pad);
951 /* capsnego for linked pads */
952 GstCaps * gst_pad_get_allowed_caps (GstPad * pad);
955 gint64 gst_pad_get_offset (GstPad *pad);
956 void gst_pad_set_offset (GstPad *pad, gint64 offset);
958 /* data passing functions to peer */
959 GstFlowReturn gst_pad_push (GstPad *pad, GstBuffer *buffer);
960 GstFlowReturn gst_pad_push_list (GstPad *pad, GstBufferList *list);
961 GstFlowReturn gst_pad_pull_range (GstPad *pad, guint64 offset, guint size,
963 gboolean gst_pad_push_event (GstPad *pad, GstEvent *event);
964 gboolean gst_pad_event_default (GstPad *pad, GstObject *parent,
967 /* data passing functions on pad */
968 GstFlowReturn gst_pad_chain (GstPad *pad, GstBuffer *buffer);
969 GstFlowReturn gst_pad_chain_list (GstPad *pad, GstBufferList *list);
970 GstFlowReturn gst_pad_get_range (GstPad *pad, guint64 offset, guint size,
972 gboolean gst_pad_send_event (GstPad *pad, GstEvent *event);
975 gboolean gst_pad_start_task (GstPad *pad, GstTaskFunction func,
976 gpointer user_data, GDestroyNotify notify);
977 gboolean gst_pad_pause_task (GstPad *pad);
978 gboolean gst_pad_stop_task (GstPad *pad);
981 void gst_pad_set_iterate_internal_links_function_full (GstPad * pad,
982 GstPadIterIntLinkFunction iterintlink,
984 GDestroyNotify notify);
985 GstIterator * gst_pad_iterate_internal_links (GstPad * pad);
986 GstIterator * gst_pad_iterate_internal_links_default (GstPad * pad, GstObject *parent);
988 #define gst_pad_set_iterate_internal_links_function(p,f) gst_pad_set_iterate_internal_links_function_full((p),(f),NULL,NULL)
990 /* generic query function */
991 gboolean gst_pad_query (GstPad *pad, GstQuery *query);
992 gboolean gst_pad_peer_query (GstPad *pad, GstQuery *query);
993 void gst_pad_set_query_function_full (GstPad *pad, GstPadQueryFunction query,
995 GDestroyNotify notify);
996 gboolean gst_pad_query_default (GstPad *pad, GstObject *parent,
999 #define gst_pad_set_query_function(p,f) gst_pad_set_query_function_full((p),(f),NULL,NULL)
1001 /* misc helper functions */
1002 gboolean gst_pad_forward (GstPad *pad, GstPadForwardFunction forward,
1003 gpointer user_data);
1007 #endif /* __GST_PAD_H__ */