2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wim.taymans@chello.be>
4 * 2005 Wim Taymans <wim@fluendo.com>
6 * gstevent.h: Header for GstEvent subsystem
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
25 #ifndef __GST_EVENT_H__
26 #define __GST_EVENT_H__
28 typedef struct _GstEvent GstEvent;
32 * @GST_EVENT_TYPE_UPSTREAM: Set if the event can travel upstream.
33 * @GST_EVENT_TYPE_DOWNSTREAM: Set if the event can travel downstream.
34 * @GST_EVENT_TYPE_SERIALIZED: Set if the event should be serialized with data
36 * @GST_EVENT_TYPE_STICKY: Set if the event is sticky on the pads.
37 * @GST_EVENT_TYPE_STICKY_MULTI: Multiple sticky events can be on a pad, each
38 * identified by the event name.
40 * #GstEventTypeFlags indicate the aspects of the different #GstEventType
41 * values. You can get the type flags of a #GstEventType with the
42 * gst_event_type_get_flags() function.
45 GST_EVENT_TYPE_UPSTREAM = 1 << 0,
46 GST_EVENT_TYPE_DOWNSTREAM = 1 << 1,
47 GST_EVENT_TYPE_SERIALIZED = 1 << 2,
48 GST_EVENT_TYPE_STICKY = 1 << 3,
49 GST_EVENT_TYPE_STICKY_MULTI = 1 << 4
53 * GST_EVENT_TYPE_BOTH:
55 * The same thing as #GST_EVENT_TYPE_UPSTREAM | #GST_EVENT_TYPE_DOWNSTREAM.
57 #define GST_EVENT_TYPE_BOTH \
58 (GST_EVENT_TYPE_UPSTREAM | GST_EVENT_TYPE_DOWNSTREAM)
60 #define GST_EVENT_MAX_STICKY 16
61 #define GST_EVENT_STICKY_SHIFT 8
62 #define GST_EVENT_NUM_SHIFT (GST_EVENT_STICKY_SHIFT + 4)
65 * GST_EVENT_MAKE_TYPE:
66 * @num: the event number to create
67 * @idx: the index in the sticky array
68 * @flags: the event flags
70 * when making custom event types, use this macro with the num and
73 #define GST_EVENT_MAKE_TYPE(num,idx,flags) \
74 (((num) << GST_EVENT_NUM_SHIFT) | ((idx) << GST_EVENT_STICKY_SHIFT) | (flags))
76 #define FLAG(name) GST_EVENT_TYPE_##name
78 #define GST_EVENT_STICKY_IDX_TYPE(type) (((type) >> GST_EVENT_STICKY_SHIFT) & 0xf)
79 #define GST_EVENT_STICKY_IDX(ev) GST_EVENT_STICKY_IDX_TYPE(GST_EVENT_TYPE(ev))
83 * @GST_EVENT_UNKNOWN: unknown event.
84 * @GST_EVENT_FLUSH_START: Start a flush operation. This event clears all data
85 * from the pipeline and unblock all streaming threads.
86 * @GST_EVENT_FLUSH_STOP: Stop a flush operation. This event resets the
87 * running-time of the pipeline.
88 * @GST_EVENT_CAPS: #GstCaps event. Notify the pad of a new media type.
89 * @GST_EVENT_SEGMENT: A new media segment follows in the dataflow. The
90 * segment events contains information for clipping buffers and
91 * converting buffer timestamps to running-time and
93 * @GST_EVENT_TAG: A new set of metadata tags has been found in the stream.
94 * @GST_EVENT_BUFFERSIZE: Notification of buffering requirements. Currently not
96 * @GST_EVENT_SINK_MESSAGE: An event that sinks turn into a message. Used to
97 * send messages that should be emitted in sync with
100 * @GST_EVENT_EOS: End-Of-Stream. No more data is to be expected to follow
101 * without a SEGMENT event.
102 * @GST_EVENT_QOS: A quality message. Used to indicate to upstream elements
103 * that the downstream elements should adjust their processing
105 * @GST_EVENT_SEEK: A request for a new playback position and rate.
106 * @GST_EVENT_NAVIGATION: Navigation events are usually used for communicating
107 * user requests, such as mouse or keyboard movements,
108 * to upstream elements.
109 * @GST_EVENT_LATENCY: Notification of new latency adjustment. Sinks will use
110 * the latency information to adjust their synchronisation.
112 * @GST_EVENT_STEP: A request for stepping through the media. Sinks will usually
113 * execute the step operation. Since: 0.10.24
114 * @GST_EVENT_RECONFIGURE: A request for upstream renegotiating caps and reconfiguring.
116 * @GST_EVENT_CUSTOM_UPSTREAM: Upstream custom event
117 * @GST_EVENT_CUSTOM_DOWNSTREAM: Downstream custom event that travels in the
119 * @GST_EVENT_CUSTOM_DOWNSTREAM_OOB: Custom out-of-band downstream event.
120 * @GST_EVENT_CUSTOM_DOWNSTREAM_STICKY: Custom sticky downstream event.
121 * @GST_EVENT_CUSTOM_BOTH: Custom upstream or downstream event.
122 * In-band when travelling downstream.
123 * @GST_EVENT_CUSTOM_BOTH_OOB: Custom upstream or downstream out-of-band event.
125 * #GstEventType lists the standard event types that can be sent in a pipeline.
127 * The custom event types can be used for private messages between elements
128 * that can't be expressed using normal
129 * GStreamer buffer passing semantics. Custom events carry an arbitrary
131 * Specific custom events are distinguished by the name of the structure.
133 /* NOTE: keep in sync with quark registration in gstevent.c */
135 GST_EVENT_UNKNOWN = GST_EVENT_MAKE_TYPE (0, 0, 0),
136 /* bidirectional events */
137 GST_EVENT_FLUSH_START = GST_EVENT_MAKE_TYPE (1, 0, FLAG(BOTH)),
138 GST_EVENT_FLUSH_STOP = GST_EVENT_MAKE_TYPE (2, 0, FLAG(BOTH) | FLAG(SERIALIZED)),
139 /* downstream serialized events */
140 GST_EVENT_CAPS = GST_EVENT_MAKE_TYPE (5, 1, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
141 GST_EVENT_SEGMENT = GST_EVENT_MAKE_TYPE (6, 2, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
142 GST_EVENT_TAG = GST_EVENT_MAKE_TYPE (7, 3, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY) | FLAG(STICKY_MULTI)),
143 GST_EVENT_BUFFERSIZE = GST_EVENT_MAKE_TYPE (8, 4, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
144 GST_EVENT_SINK_MESSAGE = GST_EVENT_MAKE_TYPE (9, 5, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY) | FLAG(STICKY_MULTI)),
145 GST_EVENT_EOS = GST_EVENT_MAKE_TYPE (10, 6, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
147 /* upstream events */
148 GST_EVENT_QOS = GST_EVENT_MAKE_TYPE (15, 0, FLAG(UPSTREAM)),
149 GST_EVENT_SEEK = GST_EVENT_MAKE_TYPE (16, 0, FLAG(UPSTREAM)),
150 GST_EVENT_NAVIGATION = GST_EVENT_MAKE_TYPE (17, 0, FLAG(UPSTREAM)),
151 GST_EVENT_LATENCY = GST_EVENT_MAKE_TYPE (18, 0, FLAG(UPSTREAM)),
152 GST_EVENT_STEP = GST_EVENT_MAKE_TYPE (19, 0, FLAG(UPSTREAM)),
153 GST_EVENT_RECONFIGURE = GST_EVENT_MAKE_TYPE (20, 0, FLAG(UPSTREAM)),
155 /* custom events start here */
156 GST_EVENT_CUSTOM_UPSTREAM = GST_EVENT_MAKE_TYPE (32, 0, FLAG(UPSTREAM)),
157 GST_EVENT_CUSTOM_DOWNSTREAM = GST_EVENT_MAKE_TYPE (32, 0, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)),
158 GST_EVENT_CUSTOM_DOWNSTREAM_OOB = GST_EVENT_MAKE_TYPE (32, 0, FLAG(DOWNSTREAM)),
159 GST_EVENT_CUSTOM_DOWNSTREAM_STICKY = GST_EVENT_MAKE_TYPE (32, 0, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY) | FLAG(STICKY_MULTI)),
160 GST_EVENT_CUSTOM_BOTH = GST_EVENT_MAKE_TYPE (32, 0, FLAG(BOTH) | FLAG(SERIALIZED)),
161 GST_EVENT_CUSTOM_BOTH_OOB = GST_EVENT_MAKE_TYPE (32, 0, FLAG(BOTH))
165 #include <gst/gstminiobject.h>
166 #include <gst/gstformat.h>
167 #include <gst/gstobject.h>
168 #include <gst/gstclock.h>
169 #include <gst/gststructure.h>
170 #include <gst/gsttaglist.h>
171 #include <gst/gstsegment.h>
172 #include <gst/gstsegment.h>
173 #include <gst/gstmessage.h>
177 GST_EXPORT GType _gst_event_type;
179 #define GST_TYPE_EVENT (_gst_event_type)
180 #define GST_IS_EVENT(obj) (GST_IS_MINI_OBJECT_TYPE (obj, GST_TYPE_EVENT))
181 #define GST_EVENT_CAST(obj) ((GstEvent *)(obj))
182 #define GST_EVENT(obj) (GST_EVENT_CAST(obj))
185 * GST_EVENT_TRACE_NAME:
187 * The name used for memory allocation tracing
189 #define GST_EVENT_TRACE_NAME "GstEvent"
193 * @event: the event to query
195 * Get the #GstEventType of the event.
197 #define GST_EVENT_TYPE(event) (GST_EVENT_CAST(event)->type)
200 * GST_EVENT_TYPE_NAME:
201 * @event: the event to query
203 * Get a constant string representation of the #GstEventType of the event.
205 #define GST_EVENT_TYPE_NAME(event) (gst_event_type_get_name(GST_EVENT_TYPE(event)))
208 * GST_EVENT_TIMESTAMP:
209 * @event: the event to query
211 * Get the #GstClockTime timestamp of the event. This is the time when the event
214 #define GST_EVENT_TIMESTAMP(event) (GST_EVENT_CAST(event)->timestamp)
218 * @event: the event to query
220 * The sequence number of @event.
222 #define GST_EVENT_SEQNUM(event) (GST_EVENT_CAST(event)->seqnum)
225 * GST_EVENT_IS_UPSTREAM:
226 * @ev: the event to query
228 * Check if an event can travel upstream.
230 #define GST_EVENT_IS_UPSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_UPSTREAM)
232 * GST_EVENT_IS_DOWNSTREAM:
233 * @ev: the event to query
235 * Check if an event can travel downstream.
237 #define GST_EVENT_IS_DOWNSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_DOWNSTREAM)
239 * GST_EVENT_IS_SERIALIZED:
240 * @ev: the event to query
242 * Check if an event is serialized with the data stream.
244 #define GST_EVENT_IS_SERIALIZED(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_SERIALIZED)
246 * GST_EVENT_IS_STICKY:
247 * @ev: the event to query
249 * Check if an event is sticky on the pads.
251 #define GST_EVENT_IS_STICKY(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_STICKY)
254 * gst_event_is_writable:
257 * Tests if you can safely write data into a event's structure or validly
258 * modify the seqnum and timestamp field.
260 #define gst_event_is_writable(ev) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (ev))
262 * gst_event_make_writable:
263 * @ev: (transfer full): a #GstEvent
265 * Makes a writable event from the given event. If the source event is
266 * already writable, this will simply return the same event. A copy will
267 * otherwise be made using gst_event_copy().
269 * Returns: (transfer full): a writable event which may or may not be the
272 #define gst_event_make_writable(ev) GST_EVENT_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (ev)))
275 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
277 * @new_event: (allow-none) (transfer none): pointer to a #GstEvent that will
278 * replace the event pointed to by @old_event.
280 * Modifies a pointer to a #GstEvent to point to a different #GstEvent. The
281 * modification is done atomically (so this is useful for ensuring thread safety
282 * in some cases), and the reference counts are updated appropriately (the old
283 * event is unreffed, the new one is reffed).
285 * Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
287 * Returns: TRUE if @new_event was different from @old_event
289 #ifdef _FOOL_GTK_DOC_
290 G_INLINE_FUNC gboolean gst_event_replace (GstEvent **old_event, GstEvent *new_event);
293 static inline gboolean
294 gst_event_replace (GstEvent **old_event, GstEvent *new_event)
296 return gst_mini_object_replace ((GstMiniObject **) old_event, (GstMiniObject *) new_event);
301 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
304 * Atomically replace the #GstEvent pointed to by @old_event with NULL and
305 * return the original event.
307 * Returns: the #GstEvent that was in @old_event
309 #ifdef _FOOL_GTK_DOC_
310 G_INLINE_FUNC GstEvent * gst_event_steal (GstEvent **old_event);
313 static inline GstEvent *
314 gst_event_steal (GstEvent **old_event)
316 return GST_EVENT_CAST (gst_mini_object_steal ((GstMiniObject **) old_event));
321 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
323 * @new_event: (allow-none) (transfer full): pointer to a #GstEvent that will
324 * replace the event pointed to by @old_event.
326 * Modifies a pointer to a #GstEvent to point to a different #GstEvent. This
327 * function is similar to gst_event_replace() except that it takes ownership of
330 * Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
332 * Returns: TRUE if @new_event was different from @old_event
334 #ifdef _FOOL_GTK_DOC_
335 G_INLINE_FUNC gboolean gst_event_take (GstEvent **old_event, GstEvent *new_event);
338 static inline gboolean
339 gst_event_take (GstEvent **old_event, GstEvent *new_event)
341 return gst_mini_object_take ((GstMiniObject **) old_event, (GstMiniObject *) new_event);
346 * @GST_QOS_TYPE_OVERFLOW: The QoS event type that is produced when downstream
347 * elements are producing data too quickly and the element can't keep up
348 * processing the data. Upstream should reduce their processing rate. This
349 * type is also used when buffers arrive early or in time.
350 * @GST_QOS_TYPE_UNDERFLOW: The QoS event type that is produced when downstream
351 * elements are producing data too slowly and need to speed up their processing
353 * @GST_QOS_TYPE_THROTTLE: The QoS event type that is produced when the
354 * application enabled throttling to limit the datarate.
356 * The different types of QoS events that can be given to the
357 * gst_event_new_qos() method.
362 GST_QOS_TYPE_OVERFLOW = 0,
363 GST_QOS_TYPE_UNDERFLOW = 1,
364 GST_QOS_TYPE_THROTTLE = 2
369 * @mini_object: the parent structure
370 * @type: the #GstEventType of the event
371 * @timestamp: the timestamp of the event
372 * @seqnum: the sequence number of the event
377 GstMiniObject mini_object;
379 /*< public >*/ /* with COW */
385 const gchar* gst_event_type_get_name (GstEventType type);
386 GQuark gst_event_type_to_quark (GstEventType type);
388 gst_event_type_get_flags (GstEventType type);
394 * @event: The event to refcount
396 * Increase the refcount of this event.
398 * Returns: (transfer full): @event (for convenience when doing assignments)
400 #ifdef _FOOL_GTK_DOC_
401 G_INLINE_FUNC GstEvent * gst_event_ref (GstEvent * event);
404 static inline GstEvent *
405 gst_event_ref (GstEvent * event)
407 return (GstEvent *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (event));
412 * @event: (transfer full): the event to refcount
414 * Decrease the refcount of an event, freeing it if the refcount reaches 0.
416 #ifdef _FOOL_GTK_DOC_
417 G_INLINE_FUNC void gst_event_unref (GstEvent * event);
421 gst_event_unref (GstEvent * event)
423 gst_mini_object_unref (GST_MINI_OBJECT_CAST (event));
429 * @event: The event to copy
431 * Copy the event using the event specific copy function.
433 * Returns: (transfer full): the new event
435 #ifdef _FOOL_GTK_DOC_
436 G_INLINE_FUNC GstEvent * gst_event_copy (const GstEvent * event);
439 static inline GstEvent *
440 gst_event_copy (const GstEvent * event)
442 return GST_EVENT_CAST (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (event)));
445 GType gst_event_get_type (void);
448 GstEvent* gst_event_new_custom (GstEventType type, GstStructure *structure) G_GNUC_MALLOC;
451 gst_event_get_structure (GstEvent *event);
452 GstStructure * gst_event_writable_structure (GstEvent *event);
454 gboolean gst_event_has_name (GstEvent *event, const gchar *name);
456 /* identifiers for events and messages */
457 guint32 gst_event_get_seqnum (GstEvent *event);
458 void gst_event_set_seqnum (GstEvent *event, guint32 seqnum);
461 GstEvent * gst_event_new_flush_start (void) G_GNUC_MALLOC;
463 GstEvent * gst_event_new_flush_stop (gboolean reset_time) G_GNUC_MALLOC;
464 void gst_event_parse_flush_stop (GstEvent *event, gboolean *reset_time);
467 GstEvent * gst_event_new_eos (void) G_GNUC_MALLOC;
470 GstEvent * gst_event_new_caps (GstCaps *caps) G_GNUC_MALLOC;
471 void gst_event_parse_caps (GstEvent *event, GstCaps **caps);
474 GstEvent* gst_event_new_segment (const GstSegment *segment) G_GNUC_MALLOC;
475 void gst_event_parse_segment (GstEvent *event, const GstSegment **segment);
476 void gst_event_copy_segment (GstEvent *event, GstSegment *segment);
479 GstEvent* gst_event_new_tag (GstTagList *taglist) G_GNUC_MALLOC;
480 void gst_event_parse_tag (GstEvent *event, GstTagList **taglist);
483 GstEvent * gst_event_new_buffer_size (GstFormat format, gint64 minsize, gint64 maxsize,
484 gboolean async) G_GNUC_MALLOC;
485 void gst_event_parse_buffer_size (GstEvent *event, GstFormat *format, gint64 *minsize,
486 gint64 *maxsize, gboolean *async);
489 GstEvent* gst_event_new_sink_message (GstMessage *msg) G_GNUC_MALLOC;
490 void gst_event_parse_sink_message (GstEvent *event, GstMessage **msg);
493 GstEvent* gst_event_new_qos (GstQOSType type, gdouble proportion,
494 GstClockTimeDiff diff, GstClockTime timestamp) G_GNUC_MALLOC;
495 void gst_event_parse_qos (GstEvent *event, GstQOSType *type,
496 gdouble *proportion, GstClockTimeDiff *diff,
497 GstClockTime *timestamp);
499 GstEvent* gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
500 GstSeekType start_type, gint64 start,
501 GstSeekType stop_type, gint64 stop) G_GNUC_MALLOC;
502 void gst_event_parse_seek (GstEvent *event, gdouble *rate, GstFormat *format,
504 GstSeekType *start_type, gint64 *start,
505 GstSeekType *stop_type, gint64 *stop);
507 /* navigation event */
508 GstEvent* gst_event_new_navigation (GstStructure *structure) G_GNUC_MALLOC;
511 GstEvent* gst_event_new_latency (GstClockTime latency) G_GNUC_MALLOC;
512 void gst_event_parse_latency (GstEvent *event, GstClockTime *latency);
515 GstEvent* gst_event_new_step (GstFormat format, guint64 amount, gdouble rate,
516 gboolean flush, gboolean intermediate) G_GNUC_MALLOC;
517 void gst_event_parse_step (GstEvent *event, GstFormat *format, guint64 *amount,
518 gdouble *rate, gboolean *flush, gboolean *intermediate);
520 /* renegotiate event */
521 GstEvent* gst_event_new_reconfigure (void) G_GNUC_MALLOC;
525 #endif /* __GST_EVENT_H__ */