We are currently experiencing downtime impacting viewing & cloning the Mesa repo, and some GitLab pages returning 503. Please see #freedesktop on IRC for more updates.

gstevent.c 30.8 KB
Newer Older
1 2 3
/* GStreamer
 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
 *                    2000 Wim Taymans <wim.taymans@chello.be>
4
 *                    2005 Wim Taymans <wim@fluendo.com>
5
 *
6
 * gstevent.c: GstEvent subsystem
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
23

24 25
/**
 * SECTION:gstevent
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
26 27
 * @short_description: Structure describing events that are passed up and down
 *                     a pipeline
28 29
 * @see_also: #GstPad, #GstElement
 *
30 31
 * The event class provides factory methods to construct and functions query
 * (parse) events.
32
 *
33 34
 * Events are usually created with gst_event_new_*() which takes event-type
 * specific parameters as arguments.
35 36
 * To send an event application will usually use gst_element_send_event() and
 * elements will use gst_pad_send_event() or gst_pad_push_event().
37 38 39 40
 * The event should be unreffed with gst_event_unref() if it has not been sent.
 *
 * Events that have been received can be parsed with their respective 
 * gst_event_parse_*() functions.
41
 *
Wim Taymans's avatar
Wim Taymans committed
42 43 44 45
 * Events are passed between elements in parallel to the data stream. Some events
 * are serialized with buffers, others are not. Some events only travel downstream,
 * others only upstream. Some events can travel both upstream and downstream. 
 * 
46 47 48
 * The events are used to signal special conditions in the datastream such as
 * EOS (end of stream) or the start of a new stream-segment.
 * Events are also used to flush the pipeline of any pending data.
Wim Taymans's avatar
Wim Taymans committed
49
 *
50 51 52 53
 * Most of the event API is used inside plugins. Applications usually only 
 * construct and use seek events. 
 * To do that gst_event_new_seek() is used to create a seek event. It takes
 * the needed parameters to specity seeking time and mode.
Wim Taymans's avatar
Wim Taymans committed
54 55 56 57 58 59 60 61 62 63
 * <example>
 * <title>performing a seek on a pipeline</title>
 *   <programlisting>
 *   GstEvent *event;
 *   gboolean result;
 *   ...
 *   // construct a seek event to play the media from second 2 to 5, flush
 *   // the pipeline to decrease latency.
 *   event = gst_event_new_seek (1.0, 
 *      GST_FORMAT_TIME, 
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
64 65 66
 *      GST_SEEK_FLAG_FLUSH,
 *      GST_SEEK_TYPE_SET, 2 * GST_SECOND,
 *      GST_SEEK_TYPE_SET, 5 * GST_SECOND);
Wim Taymans's avatar
Wim Taymans committed
67 68 69 70 71 72 73
 *   ...
 *   result = gst_element_send_event (pipeline, event);
 *   if (!result)
 *     g_warning ("seek failed");
 *   ...
 *   </programlisting>
 * </example>
Wim Taymans's avatar
Wim Taymans committed
74
 *
75
 * Last reviewed on 2006-09-6 (0.10.10)
76
 */
Wim Taymans's avatar
Wim Taymans committed
77

78

79
#include "gst_private.h"
80
#include <string.h>             /* memcpy */
81 82

#include "gstinfo.h"
83
#include "gstevent.h"
Wim Taymans's avatar
Wim Taymans committed
84
#include "gstenumtypes.h"
85
#include "gstutils.h"
Benjamin Otte's avatar
Benjamin Otte committed
86

87 88 89 90
static void gst_event_init (GTypeInstance * instance, gpointer g_class);
static void gst_event_class_init (gpointer g_class, gpointer class_data);
static void gst_event_finalize (GstEvent * event);
static GstEvent *_gst_event_copy (GstEvent * event);
91 92 93 94

void
_gst_event_initialize (void)
{
95 96 97
  g_type_class_ref (gst_event_get_type ());
  g_type_class_ref (gst_seek_flags_get_type ());
  g_type_class_ref (gst_seek_type_get_type ());
98 99
}

100 101
typedef struct
{
102 103
  const gint type;
  const gchar *name;
104 105 106 107 108 109 110 111 112 113
  GQuark quark;
} GstEventQuarks;

static GstEventQuarks event_quarks[] = {
  {GST_EVENT_UNKNOWN, "unknown", 0},
  {GST_EVENT_FLUSH_START, "flush-start", 0},
  {GST_EVENT_FLUSH_STOP, "flush-stop", 0},
  {GST_EVENT_EOS, "eos", 0},
  {GST_EVENT_NEWSEGMENT, "newsegment", 0},
  {GST_EVENT_TAG, "tag", 0},
114
  {GST_EVENT_BUFFERSIZE, "buffersize", 0},
115 116 117
  {GST_EVENT_QOS, "qos", 0},
  {GST_EVENT_SEEK, "seek", 0},
  {GST_EVENT_NAVIGATION, "navigation", 0},
118
  {GST_EVENT_LATENCY, "latency", 0},
119 120 121
  {GST_EVENT_CUSTOM_UPSTREAM, "custom-upstream", 0},
  {GST_EVENT_CUSTOM_DOWNSTREAM, "custom-downstream", 0},
  {GST_EVENT_CUSTOM_DOWNSTREAM_OOB, "custom-downstream-oob", 0},
122 123 124
  {GST_EVENT_CUSTOM_BOTH, "custom-both", 0},
  {GST_EVENT_CUSTOM_BOTH_OOB, "custom-both-oob", 0},

125 126 127
  {0, NULL, 0}
};

Stefan Kost's avatar
Stefan Kost committed
128 129 130 131 132 133
/**
 * gst_event_type_get_name:
 * @type: the event type
 *
 * Get a printable name for the given event type. Do not modify or free.
 *
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
134
 * Returns: a reference to the static name of the event.
Stefan Kost's avatar
Stefan Kost committed
135
 */
136 137 138 139 140 141 142 143 144 145 146 147
const gchar *
gst_event_type_get_name (GstEventType type)
{
  gint i;

  for (i = 0; event_quarks[i].name; i++) {
    if (type == event_quarks[i].type)
      return event_quarks[i].name;
  }
  return "unknown";
}

Stefan Kost's avatar
Stefan Kost committed
148 149 150 151 152 153 154 155
/**
 * gst_event_type_to_quark:
 * @type: the event type
 *
 * Get the unique quark for the given event type.
 *
 * Returns: the quark associated with the event type
 */
156 157 158 159 160 161 162 163 164 165 166 167
GQuark
gst_event_type_to_quark (GstEventType type)
{
  gint i;

  for (i = 0; event_quarks[i].name; i++) {
    if (type == event_quarks[i].type)
      return event_quarks[i].quark;
  }
  return 0;
}

168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185
/**
 * gst_event_type_get_flags:
 * @type: a #GstEventType
 *
 * Gets the #GstEventTypeFlags associated with @type.
 *
 * Returns: a #GstEventTypeFlags.
 */
GstEventTypeFlags
gst_event_type_get_flags (GstEventType type)
{
  GstEventTypeFlags ret;

  ret = type & ((1 << GST_EVENT_TYPE_SHIFT) - 1);

  return ret;
}

186 187 188
GType
gst_event_get_type (void)
{
189
  static GType _gst_event_type = 0;
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
190
  int i;
191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207

  if (G_UNLIKELY (_gst_event_type == 0)) {
    static const GTypeInfo event_info = {
      sizeof (GstEventClass),
      NULL,
      NULL,
      gst_event_class_init,
      NULL,
      NULL,
      sizeof (GstEvent),
      0,
      gst_event_init,
      NULL
    };

    _gst_event_type = g_type_register_static (GST_TYPE_MINI_OBJECT,
        "GstEvent", &event_info, 0);
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
208 209 210 211

    for (i = 0; event_quarks[i].name; i++) {
      event_quarks[i].quark = g_quark_from_static_string (event_quarks[i].name);
    }
212
  }
213

214
  return _gst_event_type;
215 216
}

217 218
static void
gst_event_class_init (gpointer g_class, gpointer class_data)
Wim Taymans's avatar
Wim Taymans committed
219
{
220
  GstEventClass *event_class = GST_EVENT_CLASS (g_class);
Wim Taymans's avatar
Wim Taymans committed
221

222 223 224 225 226
  event_class->mini_object_class.copy =
      (GstMiniObjectCopyFunction) _gst_event_copy;
  event_class->mini_object_class.finalize =
      (GstMiniObjectFinalizeFunction) gst_event_finalize;
}
Wim Taymans's avatar
Wim Taymans committed
227

228 229 230 231
static void
gst_event_init (GTypeInstance * instance, gpointer g_class)
{
  GstEvent *event;
232

233
  event = GST_EVENT (instance);
Wim Taymans's avatar
Wim Taymans committed
234

235
  GST_EVENT_TIMESTAMP (event) = GST_CLOCK_TIME_NONE;
Wim Taymans's avatar
Wim Taymans committed
236 237
}

238
static void
239
gst_event_finalize (GstEvent * event)
240
{
241 242 243
  g_return_if_fail (event != NULL);
  g_return_if_fail (GST_IS_EVENT (event));

244
  GST_CAT_LOG (GST_CAT_EVENT, "freeing event %p type %s", event,
245
      GST_EVENT_TYPE_NAME (event));
Wim Taymans's avatar
Wim Taymans committed
246

247 248
  if (GST_EVENT_SRC (event)) {
    gst_object_unref (GST_EVENT_SRC (event));
249
    GST_EVENT_SRC (event) = NULL;
250
  }
Wim Taymans's avatar
Wim Taymans committed
251 252 253
  if (event->structure) {
    gst_structure_set_parent_refcount (event->structure, NULL);
    gst_structure_free (event->structure);
254
  }
255 256 257 258 259 260 261
}

static GstEvent *
_gst_event_copy (GstEvent * event)
{
  GstEvent *copy;

Wim Taymans's avatar
Wim Taymans committed
262
  copy = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
263

Wim Taymans's avatar
Wim Taymans committed
264 265
  GST_EVENT_TYPE (copy) = GST_EVENT_TYPE (event);
  GST_EVENT_TIMESTAMP (copy) = GST_EVENT_TIMESTAMP (event);
266

Wim Taymans's avatar
Wim Taymans committed
267 268 269 270 271 272
  if (GST_EVENT_SRC (event)) {
    GST_EVENT_SRC (copy) = gst_object_ref (GST_EVENT_SRC (event));
  }
  if (event->structure) {
    copy->structure = gst_structure_copy (event->structure);
    gst_structure_set_parent_refcount (copy->structure,
273
        &copy->mini_object.refcount);
274 275
  }
  return copy;
276 277
}

Wim Taymans's avatar
Wim Taymans committed
278 279
static GstEvent *
gst_event_new (GstEventType type)
280
{
Wim Taymans's avatar
Wim Taymans committed
281
  GstEvent *event;
282

Wim Taymans's avatar
Wim Taymans committed
283
  event = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
284

Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
285 286
  GST_CAT_DEBUG (GST_CAT_EVENT, "creating new event %p %s %d", event,
      gst_event_type_get_name (type), type);
287

Wim Taymans's avatar
Wim Taymans committed
288 289 290
  event->type = type;
  event->src = NULL;
  event->structure = NULL;
291

Wim Taymans's avatar
Wim Taymans committed
292
  return event;
293 294
}

295
/**
Wim Taymans's avatar
Wim Taymans committed
296
 * gst_event_new_custom:
297
 * @type: The type of the new event
Wim Taymans's avatar
Wim Taymans committed
298 299
 * @structure: The structure for the event. The event will take ownership of
 * the structure.
300
 *
Wim Taymans's avatar
Wim Taymans committed
301 302 303
 * Create a new custom-typed event. This can be used for anything not
 * handled by other event-specific functions to pass an event to another
 * element.
304
 *
Wim Taymans's avatar
Wim Taymans committed
305 306 307 308 309 310 311 312
 * Make sure to allocate an event type with the #GST_EVENT_MAKE_TYPE macro,
 * assigning a free number and filling in the correct direction and
 * serialization flags.
 *
 * New custom events can also be created by subclassing the event type if
 * needed.
 *
 * Returns: The new custom event.
313
 */
314
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
315
gst_event_new_custom (GstEventType type, GstStructure * structure)
316 317 318
{
  GstEvent *event;

319 320 321 322
  /* structure must not have a parent */
  if (structure)
    g_return_val_if_fail (structure->parent_refcount == NULL, NULL);

Wim Taymans's avatar
Wim Taymans committed
323 324 325 326 327
  event = gst_event_new (type);
  if (structure) {
    gst_structure_set_parent_refcount (structure, &event->mini_object.refcount);
    event->structure = structure;
  }
328
  return event;
329 330
}

331
/**
Wim Taymans's avatar
Wim Taymans committed
332 333
 * gst_event_get_structure:
 * @event: The #GstEvent.
334
 *
Wim Taymans's avatar
Wim Taymans committed
335
 * Access the structure of the event.
336
 *
Wim Taymans's avatar
Wim Taymans committed
337 338 339 340 341
 * Returns: The structure of the event. The structure is still
 * owned by the event, which means that you should not free it and
 * that the pointer becomes invalid when you free the event.
 *
 * MT safe.
342
 */
Wim Taymans's avatar
Wim Taymans committed
343 344
const GstStructure *
gst_event_get_structure (GstEvent * event)
345
{
Wim Taymans's avatar
Wim Taymans committed
346
  g_return_val_if_fail (GST_IS_EVENT (event), NULL);
347

Wim Taymans's avatar
Wim Taymans committed
348
  return event->structure;
349
}
350

Wim Taymans's avatar
Wim Taymans committed
351
/**
Wim Taymans's avatar
Wim Taymans committed
352 353
 * gst_event_new_flush_start:
 *
354
 * Allocate a new flush start event. The flush start event can be sent
Wim Taymans's avatar
Wim Taymans committed
355
 * upstream and downstream and travels out-of-bounds with the dataflow.
356 357 358 359 360
 *
 * It marks pads as being flushing and will make them return
 * #GST_FLOW_WRONG_STATE when used for data flow with gst_pad_push(),
 * gst_pad_chain(), gst_pad_alloc_buffer(), gst_pad_get_range() and
 * gst_pad_pull_range(). Any event (except a #GST_EVENT_FLUSH_STOP) received
361
 * on a flushing pad will return %FALSE immediately.
Wim Taymans's avatar
Wim Taymans committed
362
 *
363 364
 * Elements should unlock any blocking functions and exit their streaming
 * functions as fast as possible when this event is received.
Wim Taymans's avatar
Wim Taymans committed
365
 *
366 367
 * This event is typically generated after a seek to flush out all queued data
 * in the pipeline so that the new media is played as soon as possible.
Wim Taymans's avatar
Wim Taymans committed
368
 *
Wim Taymans's avatar
Wim Taymans committed
369
 * Returns: A new flush start event.
Wim Taymans's avatar
Wim Taymans committed
370
 */
371
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
372
gst_event_new_flush_start (void)
373
{
Wim Taymans's avatar
Wim Taymans committed
374
  return gst_event_new (GST_EVENT_FLUSH_START);
375 376
}

377
/**
Wim Taymans's avatar
Wim Taymans committed
378 379
 * gst_event_new_flush_stop:
 *
380
 * Allocate a new flush stop event. The flush stop event can be sent
Wim Taymans's avatar
Wim Taymans committed
381
 * upstream and downstream and travels out-of-bounds with the dataflow.
382
 * It is typically sent after sending a FLUSH_START event to make the
Wim Taymans's avatar
Wim Taymans committed
383
 * pads accept data again.
384
 *
Wim Taymans's avatar
Wim Taymans committed
385 386
 * Elements can process this event synchronized with the dataflow since
 * the preceeding FLUSH_START event stopped the dataflow.
387
 *
Wim Taymans's avatar
Wim Taymans committed
388 389 390 391
 * This event is typically generated to complete a seek and to resume
 * dataflow.
 *
 * Returns: A new flush stop event.
392
 */
393
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
394
gst_event_new_flush_stop (void)
395
{
Wim Taymans's avatar
Wim Taymans committed
396
  return gst_event_new (GST_EVENT_FLUSH_STOP);
397 398
}

Wim Taymans's avatar
Wim Taymans committed
399
/**
Wim Taymans's avatar
Wim Taymans committed
400
 * gst_event_new_eos:
Wim Taymans's avatar
Wim Taymans committed
401
 *
Wim Taymans's avatar
Wim Taymans committed
402 403
 * Create a new EOS event. The eos event can only travel downstream
 * synchronized with the buffer flow. Elements that receive the EOS
404 405
 * event on a pad can return #GST_FLOW_UNEXPECTED as a #GstFlowReturn
 * when data after the EOS event arrives.
Wim Taymans's avatar
Wim Taymans committed
406
 *
Jan Schmidt's avatar
Jan Schmidt committed
407
 * The EOS event will travel down to the sink elements in the pipeline
408
 * which will then post the #GST_MESSAGE_EOS on the bus after they have
Jan Schmidt's avatar
Jan Schmidt committed
409
 * finished playing any buffered data.
Wim Taymans's avatar
Wim Taymans committed
410
 *
411
 * When all sinks have posted an EOS message, an EOS message is
Wim Taymans's avatar
Wim Taymans committed
412 413 414
 * forwarded to the application.
 *
 * Returns: The new EOS event.
Wim Taymans's avatar
Wim Taymans committed
415
 */
Wim Taymans's avatar
Wim Taymans committed
416 417
GstEvent *
gst_event_new_eos (void)
418
{
Wim Taymans's avatar
Wim Taymans committed
419
  return gst_event_new (GST_EVENT_EOS);
420 421
}

422
/**
423
 * gst_event_new_new_segment:
424
 * @update: is this segment an update to a previous one
Wim Taymans's avatar
Wim Taymans committed
425 426
 * @rate: a new rate for playback
 * @format: The format of the segment values
427 428 429
 * @start: the start value of the segment
 * @stop: the stop value of the segment
 * @position: stream position
Wim Taymans's avatar
Wim Taymans committed
430
 *
431 432 433 434
 * Allocate a new newsegment event with the given format/values tripplets
 *
 * This method calls gst_event_new_new_segment_full() passing a default
 * value of 1.0 for applied_rate
Tim-Philipp Müller's avatar
Tim-Philipp Müller committed
435 436
 *
 * Returns: A new newsegment event.
437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481
 */
GstEvent *
gst_event_new_new_segment (gboolean update, gdouble rate, GstFormat format,
    gint64 start, gint64 stop, gint64 position)
{
  return gst_event_new_new_segment_full (update, rate, 1.0, format, start,
      stop, position);
}

/**
 * gst_event_parse_new_segment:
 * @event: The event to query
 * @update: A pointer to the update flag of the segment
 * @rate: A pointer to the rate of the segment
 * @format: A pointer to the format of the newsegment values
 * @start: A pointer to store the start value in
 * @stop: A pointer to store the stop value in
 * @position: A pointer to store the stream time in
 *
 * Get the update flag, rate, format, start, stop and position in the 
 * newsegment event. In general, gst_event_parse_new_segment_full() should
 * be used instead of this, to also retrieve the applied_rate value of the
 * segment. See gst_event_new_new_segment_full() for a full description 
 * of the newsegment event.
 */
void
gst_event_parse_new_segment (GstEvent * event, gboolean * update,
    gdouble * rate, GstFormat * format, gint64 * start,
    gint64 * stop, gint64 * position)
{
  gst_event_parse_new_segment_full (event, update, rate, NULL, format, start,
      stop, position);
}

/**
 * gst_event_new_new_segment_full:
 * @update: Whether this segment is an update to a previous one
 * @rate: A new rate for playback
 * @applied_rate: The rate factor which has already been applied
 * @format: The format of the segment values
 * @start: The start value of the segment
 * @stop: The stop value of the segment
 * @position: stream position
 *
 * Allocate a new newsegment event with the given format/values triplets.
Wim Taymans's avatar
Wim Taymans committed
482 483
 *
 * The newsegment event marks the range of buffers to be processed. All
484
 * data not within the segment range is not to be processed. This can be
485
 * used intelligently by plugins to apply more efficient methods of skipping
486
 * unneeded data.
487
 *
488 489 490 491 492
 * The position value of the segment is used in conjunction with the start
 * value to convert the buffer timestamps into the stream time. This is 
 * usually done in sinks to report the current stream_time. 
 * @position represents the stream_time of a buffer carrying a timestamp of 
 * @start. @position cannot be -1.
493
 *
494
 * @start cannot be -1, @stop can be -1. If there
495
 * is a valid @stop given, it must be greater or equal the @start, including 
496
 * when the indicated playback @rate is < 0.
497 498 499 500 501 502 503 504
 *
 * The @applied_rate value provides information about any rate adjustment that
 * has already been made to the timestamps and content on the buffers of the 
 * stream. (@rate * @applied_rate) should always equal the rate that has been 
 * requested for playback. For example, if an element has an input segment 
 * with intended playback @rate of 2.0 and applied_rate of 1.0, it can adjust 
 * incoming timestamps and buffer content by half and output a newsegment event 
 * with @rate of 1.0 and @applied_rate of 2.0
505
 *
Wim Taymans's avatar
Wim Taymans committed
506 507
 * After a newsegment event, the buffer stream time is calculated with:
 *
508
 *   position + (TIMESTAMP(buf) - start) * ABS (rate * applied_rate)
Wim Taymans's avatar
Wim Taymans committed
509 510
 *
 * Returns: A new newsegment event.
511 512
 *
 * Since: 0.10.6
513
 */
514
GstEvent *
515 516 517
gst_event_new_new_segment_full (gboolean update, gdouble rate,
    gdouble applied_rate, GstFormat format, gint64 start, gint64 stop,
    gint64 position)
518
{
519
  g_return_val_if_fail (rate != 0.0, NULL);
520
  g_return_val_if_fail (applied_rate != 0.0, NULL);
521

522 523
  if (format == GST_FORMAT_TIME) {
    GST_CAT_INFO (GST_CAT_EVENT,
524
        "creating newsegment update %d, rate %lf, format GST_FORMAT_TIME, "
525
        "start %" GST_TIME_FORMAT ", stop %" GST_TIME_FORMAT
526 527 528
        ", position %" GST_TIME_FORMAT,
        update, rate, GST_TIME_ARGS (start),
        GST_TIME_ARGS (stop), GST_TIME_ARGS (position));
529 530
  } else {
    GST_CAT_INFO (GST_CAT_EVENT,
531
        "creating newsegment update %d, rate %lf, format %d, "
532 533
        "start %" G_GINT64_FORMAT ", stop %" G_GINT64_FORMAT ", position %"
        G_GINT64_FORMAT, update, rate, format, start, stop, position);
534
  }
535

536 537 538 539
  g_return_val_if_fail (position != -1, NULL);
  g_return_val_if_fail (start != -1, NULL);
  if (stop != -1)
    g_return_val_if_fail (start <= stop, NULL);
540

Wim Taymans's avatar
Wim Taymans committed
541
  return gst_event_new_custom (GST_EVENT_NEWSEGMENT,
542 543 544
      gst_structure_new ("GstEventNewsegment",
          "update", G_TYPE_BOOLEAN, update,
          "rate", G_TYPE_DOUBLE, rate,
545
          "applied_rate", G_TYPE_DOUBLE, applied_rate,
Wim Taymans's avatar
Wim Taymans committed
546
          "format", GST_TYPE_FORMAT, format,
547 548 549
          "start", G_TYPE_INT64, start,
          "stop", G_TYPE_INT64, stop,
          "position", G_TYPE_INT64, position, NULL));
Wim Taymans's avatar
Wim Taymans committed
550
}
551

Wim Taymans's avatar
Wim Taymans committed
552
/**
553
 * gst_event_parse_new_segment_full:
Wim Taymans's avatar
Wim Taymans committed
554
 * @event: The event to query
555
 * @update: A pointer to the update flag of the segment
Wim Taymans's avatar
Wim Taymans committed
556
 * @rate: A pointer to the rate of the segment
557
 * @applied_rate: A pointer to the applied_rate of the segment
Wim Taymans's avatar
Wim Taymans committed
558
 * @format: A pointer to the format of the newsegment values
559 560 561
 * @start: A pointer to store the start value in
 * @stop: A pointer to store the stop value in
 * @position: A pointer to store the stream time in
Wim Taymans's avatar
Wim Taymans committed
562
 *
563 564 565 566 567
 * Get the update, rate, applied_rate, format, start, stop and 
 * position in the newsegment event. See gst_event_new_new_segment_full() 
 * for a full description of the newsegment event.
 *
 * Since: 0.10.6
Wim Taymans's avatar
Wim Taymans committed
568 569
 */
void
570 571 572
gst_event_parse_new_segment_full (GstEvent * event, gboolean * update,
    gdouble * rate, gdouble * applied_rate, GstFormat * format,
    gint64 * start, gint64 * stop, gint64 * position)
Wim Taymans's avatar
Wim Taymans committed
573 574
{
  const GstStructure *structure;
575

Wim Taymans's avatar
Wim Taymans committed
576 577 578 579
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_NEWSEGMENT);

  structure = gst_event_get_structure (event);
580
  if (G_LIKELY (update))
581 582
    *update =
        g_value_get_boolean (gst_structure_get_value (structure, "update"));
583
  if (G_LIKELY (rate))
Wim Taymans's avatar
Wim Taymans committed
584
    *rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
585 586 587 588 589
  if (G_LIKELY (applied_rate))
    *applied_rate =
        g_value_get_double (gst_structure_get_value (structure,
            "applied_rate"));
  if (G_LIKELY (format))
Wim Taymans's avatar
Wim Taymans committed
590
    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
591
  if (G_LIKELY (start))
592
    *start = g_value_get_int64 (gst_structure_get_value (structure, "start"));
593
  if (G_LIKELY (stop))
594
    *stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
595
  if (G_LIKELY (position))
596 597
    *position =
        g_value_get_int64 (gst_structure_get_value (structure, "position"));
Wim Taymans's avatar
Wim Taymans committed
598
}
599

600 601 602 603 604
/**
 * gst_event_new_tag:
 * @taglist: metadata list
 *
 * Generates a metadata tag event from the given @taglist.
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
605
 *
606 607
 * Returns: a new #GstEvent
 */
Wim Taymans's avatar
Wim Taymans committed
608 609 610 611
GstEvent *
gst_event_new_tag (GstTagList * taglist)
{
  g_return_val_if_fail (taglist != NULL, NULL);
612

Wim Taymans's avatar
Wim Taymans committed
613
  return gst_event_new_custom (GST_EVENT_TAG, (GstStructure *) taglist);
614 615
}

616 617 618 619 620 621 622
/**
 * gst_event_parse_tag:
 * @event: a tag event
 * @taglist: pointer to metadata list
 *
 * Parses a tag @event and stores the results in the given @taglist location.
 */
Wim Taymans's avatar
Wim Taymans committed
623 624 625 626 627
void
gst_event_parse_tag (GstEvent * event, GstTagList ** taglist)
{
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_TAG);
628

Wim Taymans's avatar
Wim Taymans committed
629 630 631 632
  if (taglist)
    *taglist = (GstTagList *) event->structure;
}

633 634
/* buffersize event */
/**
635
 * gst_event_new_buffer_size:
Stefan Kost's avatar
Stefan Kost committed
636 637 638 639
 * @format: buffer format
 * @minsize: minimum buffer size
 * @maxsize: maximum buffer size
 * @async: thread behavior
640 641 642 643
 *
 * Create a new buffersize event. The event is sent downstream and notifies
 * elements that they should provide a buffer of the specified dimensions.
 *
644
 * When the @async flag is set, a thread boundary is prefered.
645 646 647 648
 *
 * Returns: a new #GstEvent
 */
GstEvent *
649
gst_event_new_buffer_size (GstFormat format, gint64 minsize,
650 651 652 653 654 655
    gint64 maxsize, gboolean async)
{
  GST_CAT_INFO (GST_CAT_EVENT,
      "creating buffersize format %d, minsize %" G_GINT64_FORMAT
      ", maxsize %" G_GINT64_FORMAT ", async %d", format,
      minsize, maxsize, async);
656

657 658 659 660 661 662 663 664
  return gst_event_new_custom (GST_EVENT_BUFFERSIZE,
      gst_structure_new ("GstEventBufferSize",
          "format", GST_TYPE_FORMAT, format,
          "minsize", G_TYPE_INT64, minsize,
          "maxsize", G_TYPE_INT64, maxsize,
          "async", G_TYPE_BOOLEAN, async, NULL));
}

Stefan Kost's avatar
Stefan Kost committed
665
/**
666
 * gst_event_parse_buffer_size:
Stefan Kost's avatar
Stefan Kost committed
667 668 669 670 671 672 673 674
 * @event: The event to query
 * @format: A pointer to store the format in
 * @minsize: A pointer to store the minsize in
 * @maxsize: A pointer to store the maxsize in
 * @async: A pointer to store the async-flag in
 *
 * Get the format, minsize, maxsize and async-flag in the buffersize event.
 */
675
void
676
gst_event_parse_buffer_size (GstEvent * event, GstFormat * format,
677 678 679 680 681 682
    gint64 * minsize, gint64 * maxsize, gboolean * async)
{
  const GstStructure *structure;

  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_BUFFERSIZE);
683

684 685 686 687 688 689 690 691 692 693 694 695 696
  structure = gst_event_get_structure (event);
  if (format)
    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
  if (minsize)
    *minsize =
        g_value_get_int64 (gst_structure_get_value (structure, "minsize"));
  if (maxsize)
    *maxsize =
        g_value_get_int64 (gst_structure_get_value (structure, "maxsize"));
  if (async)
    *async = g_value_get_boolean (gst_structure_get_value (structure, "async"));
}

697
/**
Wim Taymans's avatar
Wim Taymans committed
698 699 700 701 702 703 704 705
 * gst_event_new_qos:
 * @proportion: the proportion of the qos message
 * @diff: The time difference of the last Clock sync
 * @timestamp: The timestamp of the buffer
 *
 * Allocate a new qos event with the given values.
 * The QOS event is generated in an element that wants an upstream
 * element to either reduce or increase its rate because of
706
 * high/low CPU load or other resource usage such as network performance.
707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722
 * Typically sinks generate these events for each buffer they receive.
 *
 * @proportion indicates the real-time performance of the streaming in the
 * element that generated the QoS event (usually the sink). The value is
 * generally computed based on more long term statistics about the streams
 * timestamps compared to the clock.
 * A value < 1.0 indicates that the upstream element is producing data faster
 * than real-time. A value > 1.0 indicates that the upstream element is not
 * producing data fast enough. 1.0 is the ideal @proportion value. The
 * proportion value can safely be used to lower or increase the quality of
 * the element.
 *
 * @diff is the difference against the clock in running time of the last
 * buffer that caused the element to generate the QOS event. A negative value
 * means that the buffer with @timestamp arrived in time. A positive value
 * indicates how late the buffer with @timestamp was.
723
 *
724
 * @timestamp is the timestamp of the last buffer that cause the element
725 726
 * to generate the QOS event. It is expressed in running time and thus an ever
 * increasing value.
727 728
 *
 * The upstream element can use the @diff and @timestamp values to decide
729 730 731
 * whether to process more buffers. For possitive @diff, all buffers with
 * timestamp <= @timestamp + @diff will certainly arrive late in the sink
 * as well. 
732 733 734
 *
 * The application can use general event probes to intercept the QoS
 * event and implement custom application specific QoS handling.
Wim Taymans's avatar
Wim Taymans committed
735 736
 *
 * Returns: A new QOS event.
737
 */
738
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
739 740
gst_event_new_qos (gdouble proportion, GstClockTimeDiff diff,
    GstClockTime timestamp)
741
{
742
  GST_CAT_INFO (GST_CAT_EVENT,
743
      "creating qos proportion %lf, diff %" G_GINT64_FORMAT
744
      ", timestamp %" GST_TIME_FORMAT, proportion,
745
      diff, GST_TIME_ARGS (timestamp));
746

Wim Taymans's avatar
Wim Taymans committed
747 748 749 750 751 752
  return gst_event_new_custom (GST_EVENT_QOS,
      gst_structure_new ("GstEventQOS",
          "proportion", G_TYPE_DOUBLE, proportion,
          "diff", G_TYPE_INT64, diff,
          "timestamp", G_TYPE_UINT64, timestamp, NULL));
}
753

Wim Taymans's avatar
Wim Taymans committed
754 755 756 757 758 759 760
/**
 * gst_event_parse_qos:
 * @event: The event to query
 * @proportion: A pointer to store the proportion in
 * @diff: A pointer to store the diff in
 * @timestamp: A pointer to store the timestamp in
 *
761 762
 * Get the proportion, diff and timestamp in the qos event. See
 * gst_event_new_qos() for more information about the different QoS values.
Wim Taymans's avatar
Wim Taymans committed
763 764 765 766 767 768
 */
void
gst_event_parse_qos (GstEvent * event, gdouble * proportion,
    GstClockTimeDiff * diff, GstClockTime * timestamp)
{
  const GstStructure *structure;
769

Wim Taymans's avatar
Wim Taymans committed
770 771
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_QOS);
772

Wim Taymans's avatar
Wim Taymans committed
773 774 775 776 777 778 779 780 781
  structure = gst_event_get_structure (event);
  if (proportion)
    *proportion =
        g_value_get_double (gst_structure_get_value (structure, "proportion"));
  if (diff)
    *diff = g_value_get_int64 (gst_structure_get_value (structure, "diff"));
  if (timestamp)
    *timestamp =
        g_value_get_uint64 (gst_structure_get_value (structure, "timestamp"));
782
}
783 784

/**
Wim Taymans's avatar
Wim Taymans committed
785 786 787
 * gst_event_new_seek:
 * @rate: The new playback rate
 * @format: The format of the seek values
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
788
 * @flags: The optional seek flags
789 790
 * @start_type: The type and flags for the new start position
 * @start: The value of the new start position
Wim Taymans's avatar
Wim Taymans committed
791 792 793 794 795
 * @stop_type: The type and flags for the new stop position
 * @stop: The value of the new stop position
 *
 * Allocate a new seek event with the given parameters.
 *
796 797 798
 * The seek event configures playback of the pipeline between @start to @stop
 * at the speed given in @rate, also called a playback segment.
 * The @start and @stop values are expressed in @format.
799
 *
Wim Taymans's avatar
Wim Taymans committed
800 801
 * A @rate of 1.0 means normal playback rate, 2.0 means double speed.
 * Negatives values means backwards playback. A value of 0.0 for the
802 803 804
 * rate is not allowed and should be accomplished instead by PAUSING the
 * pipeline.
 *
805 806 807
 * A pipeline has a default playback segment configured with a start
 * position of 0, a stop position of -1 and a rate of 1.0. The currently
 * configured playback segment can be queried with #GST_QUERY_SEGMENT. 
808
 *
809 810 811 812
 * @start_type and @stop_type specify how to adjust the currently configured 
 * start and stop fields in @segment. Adjustments can be made relative or
 * absolute to the last configured values. A type of #GST_SEEK_TYPE_NONE means
 * that the position should not be updated.
813
 *
814
 * When the rate is positive and @start has been updated, playback will start
815 816 817 818 819
 * from the newly configured start position. 
 *
 * For negative rates, playback will start from the newly configured stop
 * position (if any). If the stop position if updated, it must be different from
 * -1 for negative rates.
820 821 822 823 824
 *
 * It is not possible to seek relative to the current playback position, to do
 * this, PAUSE the pipeline, query the current playback position with
 * #GST_QUERY_POSITION and update the playback segment current position with a
 * #GST_SEEK_TYPE_SET to the desired position.
825
 *
Wim Taymans's avatar
Wim Taymans committed
826
 * Returns: A new seek event.
827 828
 */
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
829
gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
830
    GstSeekType start_type, gint64 start, GstSeekType stop_type, gint64 stop)
831
{
832 833
  g_return_val_if_fail (rate != 0.0, NULL);

834 835 836
  if (format == GST_FORMAT_TIME) {
    GST_CAT_INFO (GST_CAT_EVENT,
        "creating seek rate %lf, format TIME, flags %d, "
837
        "start_type %d, start %" GST_TIME_FORMAT ", "
838
        "stop_type %d, stop %" GST_TIME_FORMAT,
839
        rate, flags, start_type, GST_TIME_ARGS (start),
840 841 842 843
        stop_type, GST_TIME_ARGS (stop));
  } else {
    GST_CAT_INFO (GST_CAT_EVENT,
        "creating seek rate %lf, format %d, flags %d, "
844
        "start_type %d, start %" G_GINT64_FORMAT ", "
845
        "stop_type %d, stop %" G_GINT64_FORMAT,
846
        rate, format, flags, start_type, start, stop_type, stop);
847 848
  }

Wim Taymans's avatar
Wim Taymans committed
849 850 851 852
  return gst_event_new_custom (GST_EVENT_SEEK,
      gst_structure_new ("GstEventSeek", "rate", G_TYPE_DOUBLE, rate,
          "format", GST_TYPE_FORMAT, format,
          "flags", GST_TYPE_SEEK_FLAGS, flags,
853 854
          "cur_type", GST_TYPE_SEEK_TYPE, start_type,
          "cur", G_TYPE_INT64, start,
Wim Taymans's avatar
Wim Taymans committed
855 856 857
          "stop_type", GST_TYPE_SEEK_TYPE, stop_type,
          "stop", G_TYPE_INT64, stop, NULL));
}
858

859 860 861 862 863 864
/**
 * gst_event_parse_seek:
 * @event: a seek event
 * @rate: result location for the rate
 * @format: result location for the stream format
 * @flags:  result location for the #GstSeekFlags
865 866
 * @start_type: result location for the #GstSeekType of the start position
 * @start: result location for the start postion expressed in @format
867 868 869 870 871
 * @stop_type:  result location for the #GstSeekType of the stop position
 * @stop: result location for the stop postion expressed in @format
 *
 * Parses a seek @event and stores the results in the given result locations.
 */
Wim Taymans's avatar
Wim Taymans committed
872
void
873
gst_event_parse_seek (GstEvent * event, gdouble * rate,
874 875
    GstFormat * format, GstSeekFlags * flags, GstSeekType * start_type,
    gint64 * start, GstSeekType * stop_type, gint64 * stop)
Wim Taymans's avatar
Wim Taymans committed
876 877
{
  const GstStructure *structure;
878

Wim Taymans's avatar
Wim Taymans committed
879 880
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SEEK);
881

Wim Taymans's avatar
Wim Taymans committed
882 883 884 885 886 887 888
  structure = gst_event_get_structure (event);
  if (rate)
    *rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
  if (format)
    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
  if (flags)
    *flags = g_value_get_flags (gst_structure_get_value (structure, "flags"));
889 890
  if (start_type)
    *start_type =
Wim Taymans's avatar
Wim Taymans committed
891
        g_value_get_enum (gst_structure_get_value (structure, "cur_type"));
892 893
  if (start)
    *start = g_value_get_int64 (gst_structure_get_value (structure, "cur"));
Wim Taymans's avatar
Wim Taymans committed
894 895 896 897 898 899 900
  if (stop_type)
    *stop_type =
        g_value_get_enum (gst_structure_get_value (structure, "stop_type"));
  if (stop)
    *stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
}

901 902 903 904 905 906 907 908
/**
 * gst_event_new_navigation:
 * @structure: description of the event
 *
 * Create a new navigation event from the given description.
 *
 * Returns: a new #GstEvent
 */
Wim Taymans's avatar
Wim Taymans committed
909 910 911 912
GstEvent *
gst_event_new_navigation (GstStructure * structure)
{
  g_return_val_if_fail (structure != NULL, NULL);
913

Wim Taymans's avatar
Wim Taymans committed
914
  return gst_event_new_custom (GST_EVENT_NAVIGATION, structure);
915
}
916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964

/**
 * gst_event_new_latency:
 * @latency: the new latency value
 *
 * Create a new latency event. The event is sent upstream from the sinks and
 * notifies elements that they should add an additional @latency to the
 * timestamps before synchronising against the clock.
 *
 * The latency is mostly used in live sinks and is always expressed in
 * the time format.
 *
 * Returns: a new #GstEvent
 *
 * Since: 0.10.12
 */
GstEvent *
gst_event_new_latency (GstClockTime latency)
{
  GST_CAT_INFO (GST_CAT_EVENT,
      "creating latency event %" GST_TIME_FORMAT, GST_TIME_ARGS (latency));

  return gst_event_new_custom (GST_EVENT_LATENCY,
      gst_structure_new ("GstEventLatency",
          "latency", G_TYPE_UINT64, latency, NULL));
}

/**
 * gst_event_parse_latency:
 * @event: The event to query
 * @latency: A pointer to store the latency in.
 *
 * Get the latency in the latency event.
 *
 * Since: 0.10.12
 */
void
gst_event_parse_latency (GstEvent * event, GstClockTime * latency)
{
  const GstStructure *structure;

  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_LATENCY);

  structure = gst_event_get_structure (event);
  if (latency)
    *latency =
        g_value_get_uint64 (gst_structure_get_value (structure, "latency"));
}