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., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, 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 #include <gst/gstobject.h>
65 #include <gst/gstbuffer.h>
66 #include <gst/gstbufferlist.h>
67 #include <gst/gstcaps.h>
68 #include <gst/gstpadtemplate.h>
69 #include <gst/gstevent.h>
70 #include <gst/gstquery.h>
71 #include <gst/gsttask.h>
78 #define GST_TYPE_PAD (gst_pad_get_type ())
79 #define GST_IS_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_PAD))
80 #define GST_IS_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_PAD))
81 #define GST_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_PAD, GstPad))
82 #define GST_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_PAD, GstPadClass))
83 #define GST_PAD_CAST(obj) ((GstPad*)(obj))
89 * @GST_PAD_LINK_OK : link succeeded
90 * @GST_PAD_LINK_WRONG_HIERARCHY: pads have no common grandparent
91 * @GST_PAD_LINK_WAS_LINKED : pad was already linked
92 * @GST_PAD_LINK_WRONG_DIRECTION: pads have wrong direction
93 * @GST_PAD_LINK_NOFORMAT : pads do not have common format
94 * @GST_PAD_LINK_NOSCHED : pads cannot cooperate in scheduling
95 * @GST_PAD_LINK_REFUSED : refused for some reason
97 * Result values from gst_pad_link and friends.
101 GST_PAD_LINK_WRONG_HIERARCHY = -1,
102 GST_PAD_LINK_WAS_LINKED = -2,
103 GST_PAD_LINK_WRONG_DIRECTION = -3,
104 GST_PAD_LINK_NOFORMAT = -4,
105 GST_PAD_LINK_NOSCHED = -5,
106 GST_PAD_LINK_REFUSED = -6
110 * GST_PAD_LINK_FAILED:
111 * @ret: the #GstPadLinkReturn value
113 * Macro to test if the given #GstPadLinkReturn value indicates a failed
116 #define GST_PAD_LINK_FAILED(ret) ((ret) < GST_PAD_LINK_OK)
119 * GST_PAD_LINK_SUCCESSFUL:
120 * @ret: the #GstPadLinkReturn value
122 * Macro to test if the given #GstPadLinkReturn value indicates a successful
125 #define GST_PAD_LINK_SUCCESSFUL(ret) ((ret) >= GST_PAD_LINK_OK)
129 * @GST_FLOW_OK: Data passing was ok.
130 * @GST_FLOW_NOT_LINKED: Pad is not linked.
131 * @GST_FLOW_FLUSHING: Pad is flushing.
132 * @GST_FLOW_EOS: Pad is EOS.
133 * @GST_FLOW_NOT_NEGOTIATED: Pad is not negotiated.
134 * @GST_FLOW_ERROR: Some (fatal) error occured. Element generating
135 * this error should post an error message with more
137 * @GST_FLOW_NOT_SUPPORTED: This operation is not supported.
138 * @GST_FLOW_CUSTOM_SUCCESS: Elements can use values starting from
139 * this (and higher) to define custom success
141 * @GST_FLOW_CUSTOM_SUCCESS_1: Pre-defined custom success code (define your
142 * custom success code to this to avoid compiler
144 * @GST_FLOW_CUSTOM_SUCCESS_2: Pre-defined custom success code.
145 * @GST_FLOW_CUSTOM_ERROR: Elements can use values starting from
146 * this (and lower) to define custom error codes.
147 * @GST_FLOW_CUSTOM_ERROR_1: Pre-defined custom error code (define your
148 * custom error code to this to avoid compiler
150 * @GST_FLOW_CUSTOM_ERROR_2: Pre-defined custom error code.
152 * The result of passing data to a pad.
154 * Note that the custom return values should not be exposed outside of the
157 /* FIXME 0.11: remove custom flow returns */
159 /* custom success starts here */
160 GST_FLOW_CUSTOM_SUCCESS_2 = 102,
161 GST_FLOW_CUSTOM_SUCCESS_1 = 101,
162 GST_FLOW_CUSTOM_SUCCESS = 100,
164 /* core predefined */
166 /* expected failures */
167 GST_FLOW_NOT_LINKED = -1,
168 GST_FLOW_FLUSHING = -2,
171 GST_FLOW_NOT_NEGOTIATED = -4,
173 GST_FLOW_NOT_SUPPORTED = -6,
175 /* custom error starts here */
176 GST_FLOW_CUSTOM_ERROR = -100,
177 GST_FLOW_CUSTOM_ERROR_1 = -101,
178 GST_FLOW_CUSTOM_ERROR_2 = -102
181 const gchar* gst_flow_get_name (GstFlowReturn ret);
182 GQuark gst_flow_to_quark (GstFlowReturn ret);
186 * @GST_PAD_LINK_CHECK_NOTHING: Don't check hierarchy or caps compatibility.
187 * @GST_PAD_LINK_CHECK_HIERARCHY: Check the pads have same parents/grandparents.
188 * Could be omitted if it is already known that the two elements that own the
189 * pads are in the same bin.
190 * @GST_PAD_LINK_CHECK_TEMPLATE_CAPS: Check if the pads are compatible by using
191 * their template caps. This is much faster than @GST_PAD_LINK_CHECK_CAPS, but
192 * would be unsafe e.g. if one pad has %GST_CAPS_ANY.
193 * @GST_PAD_LINK_CHECK_CAPS: Check if the pads are compatible by comparing the
194 * caps returned by gst_pad_query_caps().
195 * @GST_PAD_LINK_CHECK_DEFAULT: The default checks done when linking
196 * pads (i.e. the ones used by gst_pad_link()).
198 * The amount of checking to be done when linking pads. @GST_PAD_LINK_CHECK_CAPS
199 * and @GST_PAD_LINK_CHECK_TEMPLATE_CAPS are mutually exclusive. If both are
200 * specified, expensive but safe @GST_PAD_LINK_CHECK_CAPS are performed.
203 * Only disable some of the checks if you are 100% certain you know the link
204 * will not fail because of hierarchy/caps compatibility failures. If uncertain,
205 * use the default checks (%GST_PAD_LINK_CHECK_DEFAULT) or the regular methods
206 * for linking the pads.
211 GST_PAD_LINK_CHECK_NOTHING = 0,
212 GST_PAD_LINK_CHECK_HIERARCHY = 1 << 0,
213 GST_PAD_LINK_CHECK_TEMPLATE_CAPS = 1 << 1,
214 GST_PAD_LINK_CHECK_CAPS = 1 << 2,
216 GST_PAD_LINK_CHECK_DEFAULT = GST_PAD_LINK_CHECK_HIERARCHY | GST_PAD_LINK_CHECK_CAPS
221 * GstPadActivateFunction:
223 * @parent: the parent of @pad
225 * This function is called when the pad is activated during the element
226 * READY to PAUSED state change. By default this function will call the
227 * activate function that puts the pad in push mode but elements can
228 * override this function to activate the pad in pull mode if they wish.
230 * Returns: TRUE if the pad could be activated.
232 typedef gboolean (*GstPadActivateFunction) (GstPad *pad, GstObject *parent);
234 * GstPadActivateModeFunction:
236 * @parent: the parent of @pad
237 * @mode: the requested activation mode of @pad
238 * @active: activate or deactivate the pad.
240 * The prototype of the push and pull activate functions.
242 * Returns: TRUE if the pad could be activated or deactivated.
244 typedef gboolean (*GstPadActivateModeFunction) (GstPad *pad, GstObject *parent,
245 GstPadMode mode, gboolean active);
250 * GstPadChainFunction:
251 * @pad: the sink #GstPad that performed the chain.
252 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
253 * @parent is guaranteed to be not-NULL and remain valid during the
254 * execution of this function.
255 * @buffer: the #GstBuffer that is chained, not %NULL.
257 * A function that will be called on sinkpads when chaining buffers.
258 * The function typically processes the data contained in the buffer and
259 * either consumes the data or passes it on to the internally linked pad(s).
261 * The implementer of this function receives a refcount to @buffer and should
262 * gst_buffer_unref() when the buffer is no longer needed.
264 * When a chain function detects an error in the data stream, it must post an
265 * error on the bus and return an appropriate #GstFlowReturn value.
267 * Returns: #GST_FLOW_OK for success
269 typedef GstFlowReturn (*GstPadChainFunction) (GstPad *pad, GstObject *parent,
273 * GstPadChainListFunction:
274 * @pad: the sink #GstPad that performed the chain.
275 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
276 * @parent is guaranteed to be not-NULL and remain valid during the
277 * execution of this function.
278 * @list: the #GstBufferList that is chained, not %NULL.
280 * A function that will be called on sinkpads when chaining buffer lists.
281 * The function typically processes the data contained in the buffer list and
282 * either consumes the data or passes it on to the internally linked pad(s).
284 * The implementer of this function receives a refcount to @list and
285 * should gst_buffer_list_unref() when the list is no longer needed.
287 * When a chainlist function detects an error in the data stream, it must
288 * post an error on the bus and return an appropriate #GstFlowReturn value.
290 * Returns: #GST_FLOW_OK for success
292 typedef GstFlowReturn (*GstPadChainListFunction) (GstPad *pad, GstObject *parent,
293 GstBufferList *list);
296 * GstPadGetRangeFunction:
297 * @pad: the src #GstPad to perform the getrange on.
298 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
299 * @parent is guaranteed to be not-NULL and remain valid during the
300 * execution of this function.
301 * @offset: the offset of the range
302 * @length: the length of the range
303 * @buffer: a memory location to hold the result buffer, cannot be NULL.
305 * This function will be called on source pads when a peer element
306 * request a buffer at the specified @offset and @length. If this function
307 * returns #GST_FLOW_OK, the result buffer will be stored in @buffer. The
308 * contents of @buffer is invalid for any other return value.
310 * This function is installed on a source pad with
311 * gst_pad_set_getrange_function() and can only be called on source pads after
312 * they are successfully activated with gst_pad_activate_pull().
314 * @offset and @length are always given in byte units. @offset must normally be a value
315 * between 0 and the length in bytes of the data available on @pad. The
316 * length (duration in bytes) can be retrieved with a #GST_QUERY_DURATION or with a
317 * #GST_QUERY_SEEKING.
319 * Any @offset larger or equal than the length will make the function return
320 * #GST_FLOW_EOS, which corresponds to EOS. In this case @buffer does not
321 * contain a valid buffer.
323 * The buffer size of @buffer will only be smaller than @length when @offset is
324 * near the end of the stream. In all other cases, the size of @buffer must be
325 * exactly the requested size.
327 * It is allowed to call this function with a 0 @length and valid @offset, in
328 * which case @buffer will contain a 0-sized buffer and the function returns
331 * When this function is called with a -1 @offset, the sequentially next buffer
332 * of length @length in the stream is returned.
334 * When this function is called with a -1 @length, a buffer with a default
335 * optimal length is returned in @buffer. The length might depend on the value
338 * Returns: #GST_FLOW_OK for success and a valid buffer in @buffer. Any other
339 * return value leaves @buffer undefined.
341 typedef GstFlowReturn (*GstPadGetRangeFunction) (GstPad *pad, GstObject *parent,
342 guint64 offset, guint length,
346 * GstPadEventFunction:
347 * @pad: the #GstPad to handle the event.
348 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
349 * @parent is guaranteed to be not-NULL and remain valid during the
350 * execution of this function.
351 * @event: the #GstEvent to handle.
353 * Function signature to handle an event for the pad.
355 * Returns: TRUE if the pad could handle the event.
357 typedef gboolean (*GstPadEventFunction) (GstPad *pad, GstObject *parent,
363 * GstPadIterIntLinkFunction:
364 * @pad: The #GstPad to query.
365 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
366 * @parent is guaranteed to be not-NULL and remain valid during the
367 * execution of this function.
369 * The signature of the internal pad link iterator function.
371 * Returns: a new #GstIterator that will iterate over all pads that are
372 * linked to the given pad on the inside of the parent element.
374 * the caller must call gst_iterator_free() after usage.
376 typedef GstIterator* (*GstPadIterIntLinkFunction) (GstPad *pad, GstObject *parent);
378 /* generic query function */
380 * GstPadQueryFunction:
381 * @pad: the #GstPad to query.
382 * @parent: the parent of @pad. If the #GST_PAD_FLAG_NEED_PARENT flag is set,
383 * @parent is guaranteed to be not-NULL and remain valid during the
384 * execution of this function.
385 * @query: the #GstQuery object to execute
387 * The signature of the query function.
389 * Returns: TRUE if the query could be performed.
391 typedef gboolean (*GstPadQueryFunction) (GstPad *pad, GstObject *parent,
397 * GstPadLinkFunction:
398 * @pad: the #GstPad that is linked.
399 * @peer: the peer #GstPad of the link
401 * Function signature to handle a new link on the pad.
403 * Returns: the result of the link with the specified peer.
405 typedef GstPadLinkReturn (*GstPadLinkFunction) (GstPad *pad, GstPad *peer);
407 * GstPadUnlinkFunction:
408 * @pad: the #GstPad that is linked.
410 * Function signature to handle a unlinking the pad prom its peer.
412 typedef void (*GstPadUnlinkFunction) (GstPad *pad);
417 * GstPadForwardFunction:
418 * @pad: the #GstPad that is forwarded.
419 * @user_data: the gpointer to optional user data.
421 * A forward function is called for all internally linked pads, see
424 * Returns: TRUE if the dispatching procedure has to be stopped.
426 typedef gboolean (*GstPadForwardFunction) (GstPad *pad, gpointer user_data);
430 * @GST_PAD_PROBE_TYPE_INVALID: invalid probe type
431 * @GST_PAD_PROBE_TYPE_IDLE: probe idle pads and block
432 * @GST_PAD_PROBE_TYPE_BLOCK: probe and block pads
433 * @GST_PAD_PROBE_TYPE_BUFFER: probe buffers
434 * @GST_PAD_PROBE_TYPE_BUFFER_LIST: probe buffer lists
435 * @GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM: probe downstream events
436 * @GST_PAD_PROBE_TYPE_EVENT_UPSTREAM: probe upstream events
437 * @GST_PAD_PROBE_TYPE_EVENT_FLUSH: probe flush events. This probe has to be
438 * explicitly enabled and is not included in the
439 * @@GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM or
440 * @@GST_PAD_PROBE_TYPE_EVENT_UPSTREAM probe types.
441 * @GST_PAD_PROBE_TYPE_QUERY_DOWNSTREAM: probe downstream queries
442 * @GST_PAD_PROBE_TYPE_QUERY_UPSTREAM: probe upstream queries
443 * @GST_PAD_PROBE_TYPE_PUSH: probe push
444 * @GST_PAD_PROBE_TYPE_PULL: probe pull
446 * The different probing types that can occur. When either one of
447 * @GST_PAD_PROBE_TYPE_IDLE or @GST_PAD_PROBE_TYPE_BLOCK is used, the probe will be a
452 GST_PAD_PROBE_TYPE_INVALID = 0,
453 /* flags to control blocking */
454 GST_PAD_PROBE_TYPE_IDLE = (1 << 0),
455 GST_PAD_PROBE_TYPE_BLOCK = (1 << 1),
456 /* flags to select datatypes */
457 GST_PAD_PROBE_TYPE_BUFFER = (1 << 4),
458 GST_PAD_PROBE_TYPE_BUFFER_LIST = (1 << 5),
459 GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM = (1 << 6),
460 GST_PAD_PROBE_TYPE_EVENT_UPSTREAM = (1 << 7),
461 GST_PAD_PROBE_TYPE_EVENT_FLUSH = (1 << 8),
462 GST_PAD_PROBE_TYPE_QUERY_DOWNSTREAM = (1 << 9),
463 GST_PAD_PROBE_TYPE_QUERY_UPSTREAM = (1 << 10),
464 /* flags to select scheduling mode */
465 GST_PAD_PROBE_TYPE_PUSH = (1 << 12),
466 GST_PAD_PROBE_TYPE_PULL = (1 << 13)
469 #define GST_PAD_PROBE_TYPE_BLOCKING (GST_PAD_PROBE_TYPE_IDLE | GST_PAD_PROBE_TYPE_BLOCK)
470 #define GST_PAD_PROBE_TYPE_BLOCK_DOWNSTREAM (GST_PAD_PROBE_TYPE_BLOCK | GST_PAD_PROBE_TYPE_DATA_DOWNSTREAM)
471 #define GST_PAD_PROBE_TYPE_BLOCK_UPSTREAM (GST_PAD_PROBE_TYPE_BLOCK | GST_PAD_PROBE_TYPE_DATA_UPSTREAM)
472 #define GST_PAD_PROBE_TYPE_DATA_DOWNSTREAM (GST_PAD_PROBE_TYPE_BUFFER | GST_PAD_PROBE_TYPE_BUFFER_LIST | \
473 GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM)
474 #define GST_PAD_PROBE_TYPE_DATA_UPSTREAM (GST_PAD_PROBE_TYPE_EVENT_UPSTREAM)
475 #define GST_PAD_PROBE_TYPE_DATA_BOTH (GST_PAD_PROBE_TYPE_DATA_DOWNSTREAM | \
476 GST_PAD_PROBE_TYPE_DATA_UPSTREAM)
477 #define GST_PAD_PROBE_TYPE_EVENT_BOTH (GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM | \
478 GST_PAD_PROBE_TYPE_EVENT_UPSTREAM)
479 #define GST_PAD_PROBE_TYPE_QUERY_BOTH (GST_PAD_PROBE_TYPE_QUERY_DOWNSTREAM | \
480 GST_PAD_PROBE_TYPE_QUERY_UPSTREAM)
481 #define GST_PAD_PROBE_TYPE_ALL_BOTH (GST_PAD_PROBE_TYPE_DATA_BOTH | \
482 GST_PAD_PROBE_TYPE_QUERY_BOTH)
483 #define GST_PAD_PROBE_TYPE_SCHEDULING (GST_PAD_PROBE_TYPE_PUSH | GST_PAD_PROBE_TYPE_PULL)
487 * @GST_PAD_PROBE_OK: normal probe return value
488 * @GST_PAD_PROBE_DROP: drop data in data probes. For push mode this means that
489 * the data item is not sent downstream. For pull mode, it means that the
490 * data item is not passed upstream. In both cases, this result code
491 * returns #GST_FLOW_OK or %TRUE to the caller.
492 * @GST_PAD_PROBE_REMOVE: remove probe
493 * @GST_PAD_PROBE_PASS: pass the data item in the block probe and block on
496 * Different return values for the #GstPadProbeCallback.
502 GST_PAD_PROBE_REMOVE,
509 * @type: the current probe type
510 * @id: the id of the probe
511 * @data: type specific data, check the @type field to know the datatype.
512 * This field can be NULL.
513 * @offset: offset of pull probe, this field is valid when @type contains
514 * #GST_PAD_PROBE_TYPE_PULL
515 * @size: size of pull probe, this field is valid when @type contains
516 * #GST_PAD_PROBE_TYPE_PULL
518 * Info passed in the #GstPadProbeCallback.
520 struct _GstPadProbeInfo
522 GstPadProbeType type;
529 gpointer _gst_reserved[GST_PADDING];
532 #define GST_PAD_PROBE_INFO_TYPE(d) ((d)->type)
533 #define GST_PAD_PROBE_INFO_ID(d) ((d)->id)
534 #define GST_PAD_PROBE_INFO_DATA(d) ((d)->data)
536 #define GST_PAD_PROBE_INFO_BUFFER(d) GST_BUFFER_CAST(GST_PAD_PROBE_INFO_DATA(d))
537 #define GST_PAD_PROBE_INFO_BUFFER_LIST(d) GST_BUFFER_LIST_CAST(GST_PAD_PROBE_INFO_DATA(d))
538 #define GST_PAD_PROBE_INFO_EVENT(d) GST_EVENT_CAST(GST_PAD_PROBE_INFO_DATA(d))
539 #define GST_PAD_PROBE_INFO_QUERY(d) GST_QUERY_CAST(GST_PAD_PROBE_INFO_DATA(d))
541 #define GST_PAD_PROBE_INFO_OFFSET(d) ((d)->offset)
542 #define GST_PAD_PROBE_INFO_SIZE(d) ((d)->size)
545 * GstPadProbeCallback:
546 * @pad: the #GstPad that is blocked
547 * @info: #GstPadProbeInfo
548 * @user_data: the gpointer to optional user data.
550 * Callback used by gst_pad_add_probe(). Gets called to notify about the current
553 * The callback is allowed to modify the data pointer in @info.
555 typedef GstPadProbeReturn (*GstPadProbeCallback) (GstPad *pad, GstPadProbeInfo *info,
559 * GstPadStickyEventsForeachFunction:
561 * @event: a sticky #GstEvent.
562 * @user_data: the #gpointer to optional user data.
564 * Callback used by gst_pad_sticky_events_foreach().
566 * When this function returns %TRUE, the next event will be
567 * returned. When %FALSE is returned, gst_pad_sticky_events_foreach() will return.
569 * When @event is set to NULL, the item will be removed from the list of sticky events.
570 * When @event has been made writable, the new buffer reference can be assigned
571 * to @event. This function is responsible for unreffing the old event when
572 * removing or modifying.
574 * Returns: %TRUE if the iteration should continue
576 typedef gboolean (*GstPadStickyEventsForeachFunction) (GstPad *pad, GstEvent **event,
581 * @GST_PAD_FLAG_BLOCKED: is dataflow on a pad blocked
582 * @GST_PAD_FLAG_FLUSHING: is pad flushing
583 * @GST_PAD_FLAG_EOS: is pad in EOS state
584 * @GST_PAD_FLAG_BLOCKING: is pad currently blocking on a buffer or event
585 * @GST_PAD_FLAG_NEED_PARENT: ensure that there is a parent object before calling
586 * into the pad callbacks.
587 * @GST_PAD_FLAG_NEED_RECONFIGURE: the pad should be reconfigured/renegotiated.
588 * The flag has to be unset manually after
589 * reconfiguration happened.
590 * @GST_PAD_FLAG_PENDING_EVENTS: the pad has pending events
591 * @GST_PAD_FLAG_FIXED_CAPS: the pad is using fixed caps this means that once the
592 * caps are set on the pad, the caps query function only
593 * returns those caps.
594 * @GST_PAD_FLAG_PROXY_CAPS: the default event and query handler will forward
595 * all events and queries to the internally linked pads
596 * instead of discarding them.
597 * @GST_PAD_FLAG_PROXY_ALLOCATION: the default query handler will forward
598 * allocation queries to the internally linked pads
599 * instead of discarding them.
600 * @GST_PAD_FLAG_PROXY_SCHEDULING: the default query handler will forward
601 * scheduling queries to the internally linked pads
602 * instead of discarding them.
603 * @GST_PAD_FLAG_LAST: offset to define more flags
608 GST_PAD_FLAG_BLOCKED = (GST_OBJECT_FLAG_LAST << 0),
609 GST_PAD_FLAG_FLUSHING = (GST_OBJECT_FLAG_LAST << 1),
610 GST_PAD_FLAG_EOS = (GST_OBJECT_FLAG_LAST << 2),
611 GST_PAD_FLAG_BLOCKING = (GST_OBJECT_FLAG_LAST << 3),
612 GST_PAD_FLAG_NEED_PARENT = (GST_OBJECT_FLAG_LAST << 4),
613 GST_PAD_FLAG_NEED_RECONFIGURE = (GST_OBJECT_FLAG_LAST << 5),
614 GST_PAD_FLAG_PENDING_EVENTS = (GST_OBJECT_FLAG_LAST << 6),
615 GST_PAD_FLAG_FIXED_CAPS = (GST_OBJECT_FLAG_LAST << 7),
616 GST_PAD_FLAG_PROXY_CAPS = (GST_OBJECT_FLAG_LAST << 8),
617 GST_PAD_FLAG_PROXY_ALLOCATION = (GST_OBJECT_FLAG_LAST << 9),
618 GST_PAD_FLAG_PROXY_SCHEDULING = (GST_OBJECT_FLAG_LAST << 10),
620 GST_PAD_FLAG_LAST = (GST_OBJECT_FLAG_LAST << 16)
625 * @element_private: private data owned by the parent element
626 * @padtemplate: padtemplate for this pad
627 * @direction: the direction of the pad, cannot change after creating
630 * The #GstPad structure. Use the functions to update the variables.
636 gpointer element_private;
638 GstPadTemplate *padtemplate;
640 GstPadDirection direction;
643 /* streaming rec_lock */
644 GRecMutex stream_rec_lock;
647 /* block cond, mutex is from the object */
652 GstPadActivateFunction activatefunc;
653 gpointer activatedata;
654 GDestroyNotify activatenotify;
655 GstPadActivateModeFunction activatemodefunc;
656 gpointer activatemodedata;
657 GDestroyNotify activatemodenotify;
661 GstPadLinkFunction linkfunc;
663 GDestroyNotify linknotify;
664 GstPadUnlinkFunction unlinkfunc;
666 GDestroyNotify unlinknotify;
668 /* data transport functions */
669 GstPadChainFunction chainfunc;
671 GDestroyNotify chainnotify;
672 GstPadChainListFunction chainlistfunc;
673 gpointer chainlistdata;
674 GDestroyNotify chainlistnotify;
675 GstPadGetRangeFunction getrangefunc;
676 gpointer getrangedata;
677 GDestroyNotify getrangenotify;
678 GstPadEventFunction eventfunc;
680 GDestroyNotify eventnotify;
685 /* generic query method */
686 GstPadQueryFunction queryfunc;
688 GDestroyNotify querynotify;
691 GstPadIterIntLinkFunction iterintlinkfunc;
692 gpointer iterintlinkdata;
693 GDestroyNotify iterintlinknotify;
695 /* counts number of probes attached. */
701 gpointer _gst_reserved[GST_PADDING];
704 struct _GstPadClass {
705 GstObjectClass parent_class;
707 /* signal callbacks */
708 void (*linked) (GstPad *pad, GstPad *peer);
709 void (*unlinked) (GstPad *pad, GstPad *peer);
712 gpointer _gst_reserved[GST_PADDING];
716 /***** helper macros *****/
718 #define GST_PAD_NAME(pad) (GST_OBJECT_NAME(pad))
719 #define GST_PAD_PARENT(pad) (GST_ELEMENT_CAST(GST_OBJECT_PARENT(pad)))
720 #define GST_PAD_ELEMENT_PRIVATE(pad) (GST_PAD_CAST(pad)->element_private)
721 #define GST_PAD_PAD_TEMPLATE(pad) (GST_PAD_CAST(pad)->padtemplate)
722 #define GST_PAD_DIRECTION(pad) (GST_PAD_CAST(pad)->direction)
723 #define GST_PAD_TASK(pad) (GST_PAD_CAST(pad)->task)
724 #define GST_PAD_MODE(pad) (GST_PAD_CAST(pad)->mode)
726 #define GST_PAD_ACTIVATEFUNC(pad) (GST_PAD_CAST(pad)->activatefunc)
727 #define GST_PAD_ACTIVATEMODEFUNC(pad) (GST_PAD_CAST(pad)->activatemodefunc)
728 #define GST_PAD_CHAINFUNC(pad) (GST_PAD_CAST(pad)->chainfunc)
729 #define GST_PAD_CHAINLISTFUNC(pad) (GST_PAD_CAST(pad)->chainlistfunc)
730 #define GST_PAD_GETRANGEFUNC(pad) (GST_PAD_CAST(pad)->getrangefunc)
731 #define GST_PAD_EVENTFUNC(pad) (GST_PAD_CAST(pad)->eventfunc)
732 #define GST_PAD_QUERYFUNC(pad) (GST_PAD_CAST(pad)->queryfunc)
733 #define GST_PAD_ITERINTLINKFUNC(pad) (GST_PAD_CAST(pad)->iterintlinkfunc)
735 #define GST_PAD_PEER(pad) (GST_PAD_CAST(pad)->peer)
736 #define GST_PAD_LINKFUNC(pad) (GST_PAD_CAST(pad)->linkfunc)
737 #define GST_PAD_UNLINKFUNC(pad) (GST_PAD_CAST(pad)->unlinkfunc)
739 #define GST_PAD_IS_SRC(pad) (GST_PAD_DIRECTION(pad) == GST_PAD_SRC)
740 #define GST_PAD_IS_SINK(pad) (GST_PAD_DIRECTION(pad) == GST_PAD_SINK)
742 #define GST_PAD_IS_LINKED(pad) (GST_PAD_PEER(pad) != NULL)
744 #define GST_PAD_IS_ACTIVE(pad) (GST_PAD_MODE(pad) != GST_PAD_MODE_NONE)
746 #define GST_PAD_IS_BLOCKED(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_BLOCKED))
747 #define GST_PAD_IS_BLOCKING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_BLOCKING))
749 #define GST_PAD_IS_FLUSHING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_FLUSHING))
750 #define GST_PAD_SET_FLUSHING(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_FLUSHING))
751 #define GST_PAD_UNSET_FLUSHING(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_FLUSHING))
753 #define GST_PAD_IS_EOS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_EOS))
755 #define GST_PAD_NEEDS_RECONFIGURE(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_NEED_RECONFIGURE))
756 #define GST_PAD_HAS_PENDING_EVENTS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PENDING_EVENTS))
757 #define GST_PAD_IS_FIXED_CAPS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_FIXED_CAPS))
758 #define GST_PAD_NEEDS_PARENT(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_NEED_PARENT))
760 #define GST_PAD_IS_PROXY_CAPS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PROXY_CAPS))
761 #define GST_PAD_SET_PROXY_CAPS(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_PROXY_CAPS))
762 #define GST_PAD_UNSET_PROXY_CAPS(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_PROXY_CAPS))
764 #define GST_PAD_IS_PROXY_ALLOCATION(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PROXY_ALLOCATION))
765 #define GST_PAD_SET_PROXY_ALLOCATION(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_PROXY_ALLOCATION))
766 #define GST_PAD_UNSET_PROXY_ALLOCATION(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_PROXY_ALLOCATION))
768 #define GST_PAD_IS_PROXY_SCHEDULING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_PROXY_SCHEDULING))
769 #define GST_PAD_SET_PROXY_SCHEDULING(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_PROXY_SCHEDULING))
770 #define GST_PAD_UNSET_PROXY_SCHEDULING(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_PROXY_SCHEDULING))
773 * GST_PAD_GET_STREAM_LOCK:
776 * Get the stream lock of @pad. The stream lock is protecting the
777 * resources used in the data processing functions of @pad.
779 #define GST_PAD_GET_STREAM_LOCK(pad) (&(GST_PAD_CAST(pad)->stream_rec_lock))
781 * GST_PAD_STREAM_LOCK:
784 * Lock the stream lock of @pad.
786 #define GST_PAD_STREAM_LOCK(pad) g_rec_mutex_lock(GST_PAD_GET_STREAM_LOCK(pad))
788 * GST_PAD_STREAM_TRYLOCK:
791 * Try to Lock the stream lock of the pad, return TRUE if the lock could be
794 #define GST_PAD_STREAM_TRYLOCK(pad) g_rec_mutex_trylock(GST_PAD_GET_STREAM_LOCK(pad))
796 * GST_PAD_STREAM_UNLOCK:
799 * Unlock the stream lock of @pad.
801 #define GST_PAD_STREAM_UNLOCK(pad) g_rec_mutex_unlock(GST_PAD_GET_STREAM_LOCK(pad))
803 #define GST_PAD_BLOCK_GET_COND(pad) (&GST_PAD_CAST(pad)->block_cond)
804 #define GST_PAD_BLOCK_WAIT(pad) (g_cond_wait(GST_PAD_BLOCK_GET_COND (pad), GST_OBJECT_GET_LOCK (pad)))
805 #define GST_PAD_BLOCK_SIGNAL(pad) (g_cond_signal(GST_PAD_BLOCK_GET_COND (pad)))
806 #define GST_PAD_BLOCK_BROADCAST(pad) (g_cond_broadcast(GST_PAD_BLOCK_GET_COND (pad)))
808 GType gst_pad_get_type (void);
811 GstPad* gst_pad_new (const gchar *name, GstPadDirection direction);
812 GstPad* gst_pad_new_from_template (GstPadTemplate *templ, const gchar *name);
813 GstPad* gst_pad_new_from_static_template (GstStaticPadTemplate *templ, const gchar *name);
818 * @pad: the pad to get the name from
820 * Get a copy of the name of the pad. g_free() after usage.
824 #define gst_pad_get_name(pad) gst_object_get_name (GST_OBJECT_CAST (pad))
826 * gst_pad_get_parent:
827 * @pad: the pad to get the parent of
829 * Get the parent of @pad. This function increases the refcount
830 * of the parent object so you should gst_object_unref() it after usage.
831 * Can return NULL if the pad did not have a parent.
835 #define gst_pad_get_parent(pad) gst_object_get_parent (GST_OBJECT_CAST (pad))
837 GstPadDirection gst_pad_get_direction (GstPad *pad);
839 gboolean gst_pad_set_active (GstPad *pad, gboolean active);
840 gboolean gst_pad_is_active (GstPad *pad);
841 gboolean gst_pad_activate_mode (GstPad *pad, GstPadMode mode,
844 gulong gst_pad_add_probe (GstPad *pad,
845 GstPadProbeType mask,
846 GstPadProbeCallback callback,
848 GDestroyNotify destroy_data);
849 void gst_pad_remove_probe (GstPad *pad, gulong id);
851 gboolean gst_pad_is_blocked (GstPad *pad);
852 gboolean gst_pad_is_blocking (GstPad *pad);
854 void gst_pad_mark_reconfigure (GstPad *pad);
855 gboolean gst_pad_needs_reconfigure (GstPad *pad);
856 gboolean gst_pad_check_reconfigure (GstPad *pad);
858 void gst_pad_set_element_private (GstPad *pad, gpointer priv);
859 gpointer gst_pad_get_element_private (GstPad *pad);
861 GstPadTemplate* gst_pad_get_pad_template (GstPad *pad);
863 GstEvent* gst_pad_get_sticky_event (GstPad *pad, GstEventType event_type,
865 void gst_pad_sticky_events_foreach (GstPad *pad, GstPadStickyEventsForeachFunction foreach_func, gpointer user_data);
867 /* data passing setup functions */
868 void gst_pad_set_activate_function_full (GstPad *pad,
869 GstPadActivateFunction activate,
871 GDestroyNotify notify);
872 void gst_pad_set_activatemode_function_full (GstPad *pad,
873 GstPadActivateModeFunction activatemode,
875 GDestroyNotify notify);
876 /* data passing functions */
877 void gst_pad_set_chain_function_full (GstPad *pad,
878 GstPadChainFunction chain,
880 GDestroyNotify notify);
881 void gst_pad_set_chain_list_function_full (GstPad *pad,
882 GstPadChainListFunction chainlist,
884 GDestroyNotify notify);
885 void gst_pad_set_getrange_function_full (GstPad *pad,
886 GstPadGetRangeFunction get,
888 GDestroyNotify notify);
889 void gst_pad_set_event_function_full (GstPad *pad,
890 GstPadEventFunction event,
892 GDestroyNotify notify);
894 #define gst_pad_set_activate_function(p,f) gst_pad_set_activate_function_full((p),(f),NULL,NULL)
895 #define gst_pad_set_activatemode_function(p,f) gst_pad_set_activatemode_function_full((p),(f),NULL,NULL)
896 #define gst_pad_set_chain_function(p,f) gst_pad_set_chain_function_full((p),(f),NULL,NULL)
897 #define gst_pad_set_chain_list_function(p,f) gst_pad_set_chain_list_function_full((p),(f),NULL,NULL)
898 #define gst_pad_set_getrange_function(p,f) gst_pad_set_getrange_function_full((p),(f),NULL,NULL)
899 #define gst_pad_set_event_function(p,f) gst_pad_set_event_function_full((p),(f),NULL,NULL)
902 void gst_pad_set_link_function_full (GstPad *pad,
903 GstPadLinkFunction link,
905 GDestroyNotify notify);
906 void gst_pad_set_unlink_function_full (GstPad *pad,
907 GstPadUnlinkFunction unlink,
909 GDestroyNotify notify);
911 #define gst_pad_set_link_function(p,f) gst_pad_set_link_function_full((p),(f),NULL,NULL)
912 #define gst_pad_set_unlink_function(p,f) gst_pad_set_unlink_function_full((p),(f),NULL,NULL)
914 gboolean gst_pad_can_link (GstPad *srcpad, GstPad *sinkpad);
915 GstPadLinkReturn gst_pad_link (GstPad *srcpad, GstPad *sinkpad);
916 GstPadLinkReturn gst_pad_link_full (GstPad *srcpad, GstPad *sinkpad, GstPadLinkCheck flags);
917 gboolean gst_pad_unlink (GstPad *srcpad, GstPad *sinkpad);
918 gboolean gst_pad_is_linked (GstPad *pad);
920 GstPad* gst_pad_get_peer (GstPad *pad);
922 GstCaps* gst_pad_get_pad_template_caps (GstPad *pad);
924 /* capsnego function for linked/unlinked pads */
925 GstCaps * gst_pad_get_current_caps (GstPad * pad);
926 gboolean gst_pad_has_current_caps (GstPad * pad);
928 /* capsnego for linked pads */
929 GstCaps * gst_pad_get_allowed_caps (GstPad * pad);
932 gint64 gst_pad_get_offset (GstPad *pad);
933 void gst_pad_set_offset (GstPad *pad, gint64 offset);
935 /* data passing functions to peer */
936 GstFlowReturn gst_pad_push (GstPad *pad, GstBuffer *buffer);
937 GstFlowReturn gst_pad_push_list (GstPad *pad, GstBufferList *list);
938 GstFlowReturn gst_pad_pull_range (GstPad *pad, guint64 offset, guint size,
940 gboolean gst_pad_push_event (GstPad *pad, GstEvent *event);
941 gboolean gst_pad_event_default (GstPad *pad, GstObject *parent,
944 /* data passing functions on pad */
945 GstFlowReturn gst_pad_chain (GstPad *pad, GstBuffer *buffer);
946 GstFlowReturn gst_pad_chain_list (GstPad *pad, GstBufferList *list);
947 GstFlowReturn gst_pad_get_range (GstPad *pad, guint64 offset, guint size,
949 gboolean gst_pad_send_event (GstPad *pad, GstEvent *event);
952 gboolean gst_pad_start_task (GstPad *pad, GstTaskFunction func,
953 gpointer user_data, GDestroyNotify notify);
954 gboolean gst_pad_pause_task (GstPad *pad);
955 gboolean gst_pad_stop_task (GstPad *pad);
958 void gst_pad_set_iterate_internal_links_function_full (GstPad * pad,
959 GstPadIterIntLinkFunction iterintlink,
961 GDestroyNotify notify);
962 GstIterator * gst_pad_iterate_internal_links (GstPad * pad);
963 GstIterator * gst_pad_iterate_internal_links_default (GstPad * pad, GstObject *parent);
965 #define gst_pad_set_iterate_internal_links_function(p,f) gst_pad_set_iterate_internal_links_function_full((p),(f),NULL,NULL)
967 /* generic query function */
968 gboolean gst_pad_query (GstPad *pad, GstQuery *query);
969 gboolean gst_pad_peer_query (GstPad *pad, GstQuery *query);
970 void gst_pad_set_query_function_full (GstPad *pad, GstPadQueryFunction query,
972 GDestroyNotify notify);
973 gboolean gst_pad_query_default (GstPad *pad, GstObject *parent,
976 #define gst_pad_set_query_function(p,f) gst_pad_set_query_function_full((p),(f),NULL,NULL)
978 /* misc helper functions */
979 gboolean gst_pad_forward (GstPad *pad, GstPadForwardFunction forward,
982 const gchar * gst_pad_mode_get_name (GstPadMode mode);
986 #endif /* __GST_PAD_H__ */