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 * gstquery.c: GstQueryType registration and Query parsing/creation
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., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
26 * @short_description: Provide functions to create queries, and to set and parse
28 * @see_also: #GstPad, #GstElement
30 * Queries can be performed on pads (gst_pad_query()) and elements
31 * (gst_element_query()). Please note that some queries might need a running
34 * Queries can be created using the gst_query_new_*() functions.
35 * Query values can be set using gst_query_set_*(), and parsed using
36 * gst_query_parse_*() helpers.
38 * The following example shows how to query the duration of a pipeline:
41 * <title>Query duration on a pipeline</title>
45 * query = gst_query_new_duration (GST_FORMAT_TIME);
46 * res = gst_element_query (pipeline, query);
49 * gst_query_parse_duration (query, NULL, &duration);
50 * g_print ("duration = %"GST_TIME_FORMAT, GST_TIME_ARGS (duration));
53 * g_print ("duration query failed...");
55 * gst_query_unref (query);
59 * Last reviewed on 2012-03-29 (0.11.3)
63 #include "gst_private.h"
67 #include "gstenumtypes.h"
70 #include "gstbufferpool.h"
72 GST_DEBUG_CATEGORY_STATIC (gst_query_debug);
73 #define GST_CAT_DEFAULT gst_query_debug
75 static GType _gst_query_type = 0;
81 GstStructure *structure;
84 #define GST_QUERY_STRUCTURE(q) (((GstQueryImpl *)(q))->structure)
94 static GstQueryQuarks query_quarks[] = {
95 {GST_QUERY_UNKNOWN, "unknown", 0},
96 {GST_QUERY_POSITION, "position", 0},
97 {GST_QUERY_DURATION, "duration", 0},
98 {GST_QUERY_LATENCY, "latency", 0},
99 {GST_QUERY_JITTER, "jitter", 0},
100 {GST_QUERY_RATE, "rate", 0},
101 {GST_QUERY_SEEKING, "seeking", 0},
102 {GST_QUERY_SEGMENT, "segment", 0},
103 {GST_QUERY_CONVERT, "convert", 0},
104 {GST_QUERY_FORMATS, "formats", 0},
105 {GST_QUERY_BUFFERING, "buffering", 0},
106 {GST_QUERY_CUSTOM, "custom", 0},
107 {GST_QUERY_URI, "uri", 0},
108 {GST_QUERY_ALLOCATION, "allocation", 0},
109 {GST_QUERY_SCHEDULING, "scheduling", 0},
110 {GST_QUERY_ACCEPT_CAPS, "accept-caps", 0},
111 {GST_QUERY_CAPS, "caps", 0},
112 {GST_QUERY_DRAIN, "drain", 0},
113 {GST_QUERY_CONTEXT, "context", 0},
118 GST_DEFINE_MINI_OBJECT_TYPE (GstQuery, gst_query);
121 _priv_gst_query_initialize (void)
125 _gst_query_type = gst_query_get_type ();
127 GST_DEBUG_CATEGORY_INIT (gst_query_debug, "query", 0, "query system");
129 for (i = 0; query_quarks[i].name; i++) {
130 query_quarks[i].quark = g_quark_from_static_string (query_quarks[i].name);
135 * gst_query_type_get_name:
136 * @type: the query type
138 * Get a printable name for the given query type. Do not modify or free.
140 * Returns: a reference to the static name of the query.
143 gst_query_type_get_name (GstQueryType type)
147 for (i = 0; query_quarks[i].name; i++) {
148 if (type == query_quarks[i].type)
149 return query_quarks[i].name;
155 * gst_query_type_to_quark:
156 * @type: the query type
158 * Get the unique quark for the given query type.
160 * Returns: the quark associated with the query type
163 gst_query_type_to_quark (GstQueryType type)
167 for (i = 0; query_quarks[i].name; i++) {
168 if (type == query_quarks[i].type)
169 return query_quarks[i].quark;
175 * gst_query_type_get_flags:
176 * @type: a #GstQueryType
178 * Gets the #GstQueryTypeFlags associated with @type.
180 * Returns: a #GstQueryTypeFlags.
183 gst_query_type_get_flags (GstQueryType type)
185 GstQueryTypeFlags ret;
187 ret = type & ((1 << GST_QUERY_NUM_SHIFT) - 1);
193 _gst_query_free (GstQuery * query)
197 g_return_if_fail (query != NULL);
199 s = GST_QUERY_STRUCTURE (query);
201 gst_structure_set_parent_refcount (s, NULL);
202 gst_structure_free (s);
205 g_slice_free1 (sizeof (GstQueryImpl), query);
209 _gst_query_copy (GstQuery * query)
214 s = GST_QUERY_STRUCTURE (query);
216 s = gst_structure_copy (s);
218 copy = gst_query_new_custom (query->type, s);
224 * gst_query_new_position:
225 * @format: the default #GstFormat for the new query
227 * Constructs a new query stream position query object. Use gst_query_unref()
228 * when done with it. A position query is used to query the current position
229 * of playback in the streams, in some format.
231 * Free-function: gst_query_unref
233 * Returns: (transfer full): a new #GstQuery
236 gst_query_new_position (GstFormat format)
239 GstStructure *structure;
241 structure = gst_structure_new_id (GST_QUARK (QUERY_POSITION),
242 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
243 GST_QUARK (CURRENT), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
245 query = gst_query_new_custom (GST_QUERY_POSITION, structure);
251 * gst_query_set_position:
252 * @query: a #GstQuery with query type GST_QUERY_POSITION
253 * @format: the requested #GstFormat
254 * @cur: the position to set
256 * Answer a position query by setting the requested value in the given format.
259 gst_query_set_position (GstQuery * query, GstFormat format, gint64 cur)
263 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_POSITION);
265 s = GST_QUERY_STRUCTURE (query);
266 g_return_if_fail (format == g_value_get_enum (gst_structure_id_get_value (s,
267 GST_QUARK (FORMAT))));
269 gst_structure_id_set (s,
270 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
271 GST_QUARK (CURRENT), G_TYPE_INT64, cur, NULL);
275 * gst_query_parse_position:
276 * @query: a #GstQuery
277 * @format: (out) (allow-none): the storage for the #GstFormat of the
278 * position values (may be NULL)
279 * @cur: (out) (allow-none): the storage for the current position (may be NULL)
281 * Parse a position query, writing the format into @format, and the position
282 * into @cur, if the respective parameters are non-NULL.
285 gst_query_parse_position (GstQuery * query, GstFormat * format, gint64 * cur)
287 GstStructure *structure;
289 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_POSITION);
291 structure = GST_QUERY_STRUCTURE (query);
294 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
295 GST_QUARK (FORMAT)));
297 *cur = g_value_get_int64 (gst_structure_id_get_value (structure,
298 GST_QUARK (CURRENT)));
303 * gst_query_new_duration:
304 * @format: the #GstFormat for this duration query
306 * Constructs a new stream duration query object to query in the given format.
307 * Use gst_query_unref() when done with it. A duration query will give the
308 * total length of the stream.
310 * Free-function: gst_query_unref
312 * Returns: (transfer full): a new #GstQuery
315 gst_query_new_duration (GstFormat format)
318 GstStructure *structure;
320 structure = gst_structure_new_id (GST_QUARK (QUERY_DURATION),
321 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
322 GST_QUARK (DURATION), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
324 query = gst_query_new_custom (GST_QUERY_DURATION, structure);
330 * gst_query_set_duration:
331 * @query: a #GstQuery
332 * @format: the #GstFormat for the duration
333 * @duration: the duration of the stream
335 * Answer a duration query by setting the requested value in the given format.
338 gst_query_set_duration (GstQuery * query, GstFormat format, gint64 duration)
342 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_DURATION);
344 s = GST_QUERY_STRUCTURE (query);
345 g_return_if_fail (format == g_value_get_enum (gst_structure_id_get_value (s,
346 GST_QUARK (FORMAT))));
347 gst_structure_id_set (s, GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
348 GST_QUARK (DURATION), G_TYPE_INT64, duration, NULL);
352 * gst_query_parse_duration:
353 * @query: a #GstQuery
354 * @format: (out) (allow-none): the storage for the #GstFormat of the duration
356 * @duration: (out) (allow-none): the storage for the total duration, or NULL.
358 * Parse a duration query answer. Write the format of the duration into @format,
359 * and the value into @duration, if the respective variables are non-NULL.
362 gst_query_parse_duration (GstQuery * query, GstFormat * format,
365 GstStructure *structure;
367 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_DURATION);
369 structure = GST_QUERY_STRUCTURE (query);
372 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
373 GST_QUARK (FORMAT)));
375 *duration = g_value_get_int64 (gst_structure_id_get_value (structure,
376 GST_QUARK (DURATION)));
380 * gst_query_new_latency:
382 * Constructs a new latency query object.
383 * Use gst_query_unref() when done with it. A latency query is usually performed
384 * by sinks to compensate for additional latency introduced by elements in the
387 * Free-function: gst_query_unref
389 * Returns: (transfer full): a #GstQuery
392 gst_query_new_latency (void)
395 GstStructure *structure;
397 structure = gst_structure_new_id (GST_QUARK (QUERY_LATENCY),
398 GST_QUARK (LIVE), G_TYPE_BOOLEAN, FALSE,
399 GST_QUARK (MIN_LATENCY), G_TYPE_UINT64, G_GUINT64_CONSTANT (0),
400 GST_QUARK (MAX_LATENCY), G_TYPE_UINT64, G_GUINT64_CONSTANT (-1), NULL);
402 query = gst_query_new_custom (GST_QUERY_LATENCY, structure);
408 * gst_query_set_latency:
409 * @query: a #GstQuery
410 * @live: if there is a live element upstream
411 * @min_latency: the minimal latency of the upstream elements
412 * @max_latency: the maximal latency of the upstream elements
414 * Answer a latency query by setting the requested values in the given format.
417 gst_query_set_latency (GstQuery * query, gboolean live,
418 GstClockTime min_latency, GstClockTime max_latency)
420 GstStructure *structure;
422 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_LATENCY);
424 structure = GST_QUERY_STRUCTURE (query);
425 gst_structure_id_set (structure,
426 GST_QUARK (LIVE), G_TYPE_BOOLEAN, live,
427 GST_QUARK (MIN_LATENCY), G_TYPE_UINT64, min_latency,
428 GST_QUARK (MAX_LATENCY), G_TYPE_UINT64, max_latency, NULL);
432 * gst_query_parse_latency:
433 * @query: a #GstQuery
434 * @live: (out) (allow-none): storage for live or NULL
435 * @min_latency: (out) (allow-none): the storage for the min latency or NULL
436 * @max_latency: (out) (allow-none): the storage for the max latency or NULL
438 * Parse a latency query answer.
441 gst_query_parse_latency (GstQuery * query, gboolean * live,
442 GstClockTime * min_latency, GstClockTime * max_latency)
444 GstStructure *structure;
446 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_LATENCY);
448 structure = GST_QUERY_STRUCTURE (query);
451 g_value_get_boolean (gst_structure_id_get_value (structure,
454 *min_latency = g_value_get_uint64 (gst_structure_id_get_value (structure,
455 GST_QUARK (MIN_LATENCY)));
457 *max_latency = g_value_get_uint64 (gst_structure_id_get_value (structure,
458 GST_QUARK (MAX_LATENCY)));
462 * gst_query_new_convert:
463 * @src_format: the source #GstFormat for the new query
464 * @value: the value to convert
465 * @dest_format: the target #GstFormat
467 * Constructs a new convert query object. Use gst_query_unref()
468 * when done with it. A convert query is used to ask for a conversion between
469 * one format and another.
471 * Free-function: gst_query_unref
473 * Returns: (transfer full): a #GstQuery
476 gst_query_new_convert (GstFormat src_format, gint64 value,
477 GstFormat dest_format)
480 GstStructure *structure;
482 structure = gst_structure_new_id (GST_QUARK (QUERY_CONVERT),
483 GST_QUARK (SRC_FORMAT), GST_TYPE_FORMAT, src_format,
484 GST_QUARK (SRC_VALUE), G_TYPE_INT64, value,
485 GST_QUARK (DEST_FORMAT), GST_TYPE_FORMAT, dest_format,
486 GST_QUARK (DEST_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
488 query = gst_query_new_custom (GST_QUERY_CONVERT, structure);
494 * gst_query_set_convert:
495 * @query: a #GstQuery
496 * @src_format: the source #GstFormat
497 * @src_value: the source value
498 * @dest_format: the destination #GstFormat
499 * @dest_value: the destination value
501 * Answer a convert query by setting the requested values.
504 gst_query_set_convert (GstQuery * query, GstFormat src_format, gint64 src_value,
505 GstFormat dest_format, gint64 dest_value)
507 GstStructure *structure;
509 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONVERT);
511 structure = GST_QUERY_STRUCTURE (query);
512 gst_structure_id_set (structure,
513 GST_QUARK (SRC_FORMAT), GST_TYPE_FORMAT, src_format,
514 GST_QUARK (SRC_VALUE), G_TYPE_INT64, src_value,
515 GST_QUARK (DEST_FORMAT), GST_TYPE_FORMAT, dest_format,
516 GST_QUARK (DEST_VALUE), G_TYPE_INT64, dest_value, NULL);
520 * gst_query_parse_convert:
521 * @query: a #GstQuery
522 * @src_format: (out) (allow-none): the storage for the #GstFormat of the
523 * source value, or NULL
524 * @src_value: (out) (allow-none): the storage for the source value, or NULL
525 * @dest_format: (out) (allow-none): the storage for the #GstFormat of the
526 * destination value, or NULL
527 * @dest_value: (out) (allow-none): the storage for the destination value,
530 * Parse a convert query answer. Any of @src_format, @src_value, @dest_format,
531 * and @dest_value may be NULL, in which case that value is omitted.
534 gst_query_parse_convert (GstQuery * query, GstFormat * src_format,
535 gint64 * src_value, GstFormat * dest_format, gint64 * dest_value)
537 GstStructure *structure;
539 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONVERT);
541 structure = GST_QUERY_STRUCTURE (query);
544 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
545 GST_QUARK (SRC_FORMAT)));
547 *src_value = g_value_get_int64 (gst_structure_id_get_value (structure,
548 GST_QUARK (SRC_VALUE)));
551 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
552 GST_QUARK (DEST_FORMAT)));
554 *dest_value = g_value_get_int64 (gst_structure_id_get_value (structure,
555 GST_QUARK (DEST_VALUE)));
559 * gst_query_new_segment:
560 * @format: the #GstFormat for the new query
562 * Constructs a new segment query object. Use gst_query_unref()
563 * when done with it. A segment query is used to discover information about the
564 * currently configured segment for playback.
566 * Free-function: gst_query_unref
568 * Returns: (transfer full): a new #GstQuery
571 gst_query_new_segment (GstFormat format)
574 GstStructure *structure;
576 structure = gst_structure_new_id (GST_QUARK (QUERY_SEGMENT),
577 GST_QUARK (RATE), G_TYPE_DOUBLE, (gdouble) 0.0,
578 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
579 GST_QUARK (START_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
580 GST_QUARK (STOP_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
582 query = gst_query_new_custom (GST_QUERY_SEGMENT, structure);
588 * gst_query_set_segment:
589 * @query: a #GstQuery
590 * @rate: the rate of the segment
591 * @format: the #GstFormat of the segment values (@start_value and @stop_value)
592 * @start_value: the start value
593 * @stop_value: the stop value
595 * Answer a segment query by setting the requested values. The normal
596 * playback segment of a pipeline is 0 to duration at the default rate of
597 * 1.0. If a seek was performed on the pipeline to play a different
598 * segment, this query will return the range specified in the last seek.
600 * @start_value and @stop_value will respectively contain the configured
601 * playback range start and stop values expressed in @format.
602 * The values are always between 0 and the duration of the media and
603 * @start_value <= @stop_value. @rate will contain the playback rate. For
604 * negative rates, playback will actually happen from @stop_value to
608 gst_query_set_segment (GstQuery * query, gdouble rate, GstFormat format,
609 gint64 start_value, gint64 stop_value)
611 GstStructure *structure;
613 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEGMENT);
615 structure = GST_QUERY_STRUCTURE (query);
616 gst_structure_id_set (structure,
617 GST_QUARK (RATE), G_TYPE_DOUBLE, rate,
618 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
619 GST_QUARK (START_VALUE), G_TYPE_INT64, start_value,
620 GST_QUARK (STOP_VALUE), G_TYPE_INT64, stop_value, NULL);
624 * gst_query_parse_segment:
625 * @query: a #GstQuery
626 * @rate: (out) (allow-none): the storage for the rate of the segment, or NULL
627 * @format: (out) (allow-none): the storage for the #GstFormat of the values,
629 * @start_value: (out) (allow-none): the storage for the start value, or NULL
630 * @stop_value: (out) (allow-none): the storage for the stop value, or NULL
632 * Parse a segment query answer. Any of @rate, @format, @start_value, and
633 * @stop_value may be NULL, which will cause this value to be omitted.
635 * See gst_query_set_segment() for an explanation of the function arguments.
638 gst_query_parse_segment (GstQuery * query, gdouble * rate, GstFormat * format,
639 gint64 * start_value, gint64 * stop_value)
641 GstStructure *structure;
643 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEGMENT);
645 structure = GST_QUERY_STRUCTURE (query);
647 *rate = g_value_get_double (gst_structure_id_get_value (structure,
651 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
652 GST_QUARK (FORMAT)));
654 *start_value = g_value_get_int64 (gst_structure_id_get_value (structure,
655 GST_QUARK (START_VALUE)));
657 *stop_value = g_value_get_int64 (gst_structure_id_get_value (structure,
658 GST_QUARK (STOP_VALUE)));
662 * gst_query_new_custom:
663 * @type: the query type
664 * @structure: a structure for the query
666 * Constructs a new custom query object. Use gst_query_unref()
669 * Free-function: gst_query_unref
671 * Returns: (transfer full): a new #GstQuery
674 gst_query_new_custom (GstQueryType type, GstStructure * structure)
678 query = g_slice_new0 (GstQueryImpl);
680 GST_DEBUG ("creating new query %p %s", query, gst_query_type_get_name (type));
683 /* structure must not have a parent */
684 if (!gst_structure_set_parent_refcount (structure,
685 &query->query.mini_object.refcount))
689 gst_mini_object_init (GST_MINI_OBJECT_CAST (query), 0, _gst_query_type,
690 (GstMiniObjectCopyFunction) _gst_query_copy, NULL,
691 (GstMiniObjectFreeFunction) _gst_query_free);
693 GST_QUERY_TYPE (query) = type;
694 GST_QUERY_STRUCTURE (query) = structure;
696 return GST_QUERY_CAST (query);
701 g_slice_free1 (sizeof (GstQueryImpl), query);
702 g_warning ("structure is already owned by another object");
708 * gst_query_get_structure:
709 * @query: a #GstQuery
711 * Get the structure of a query.
713 * Returns: (transfer none): the #GstStructure of the query. The structure is
714 * still owned by the query and will therefore be freed when the query
718 gst_query_get_structure (GstQuery * query)
720 g_return_val_if_fail (GST_IS_QUERY (query), NULL);
722 return GST_QUERY_STRUCTURE (query);
726 * gst_query_writable_structure:
727 * @query: a #GstQuery
729 * Get the structure of a query. This method should be called with a writable
730 * @query so that the returned structure is guranteed to be writable.
732 * Returns: (transfer none): the #GstStructure of the query. The structure is
733 * still owned by the query and will therefore be freed when the query
737 gst_query_writable_structure (GstQuery * query)
739 g_return_val_if_fail (GST_IS_QUERY (query), NULL);
740 g_return_val_if_fail (gst_query_is_writable (query), NULL);
742 return GST_QUERY_STRUCTURE (query);
746 * gst_query_new_seeking:
747 * @format: the default #GstFormat for the new query
749 * Constructs a new query object for querying seeking properties of
752 * Free-function: gst_query_unref
754 * Returns: (transfer full): a new #GstQuery
757 gst_query_new_seeking (GstFormat format)
760 GstStructure *structure;
762 structure = gst_structure_new_id (GST_QUARK (QUERY_SEEKING),
763 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
764 GST_QUARK (SEEKABLE), G_TYPE_BOOLEAN, FALSE,
765 GST_QUARK (SEGMENT_START), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
766 GST_QUARK (SEGMENT_END), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
768 query = gst_query_new_custom (GST_QUERY_SEEKING, structure);
774 * gst_query_set_seeking:
775 * @query: a #GstQuery
776 * @format: the format to set for the @segment_start and @segment_end values
777 * @seekable: the seekable flag to set
778 * @segment_start: the segment_start to set
779 * @segment_end: the segment_end to set
781 * Set the seeking query result fields in @query.
784 gst_query_set_seeking (GstQuery * query, GstFormat format,
785 gboolean seekable, gint64 segment_start, gint64 segment_end)
787 GstStructure *structure;
789 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEEKING);
790 g_return_if_fail (gst_query_is_writable (query));
792 structure = GST_QUERY_STRUCTURE (query);
793 gst_structure_id_set (structure,
794 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
795 GST_QUARK (SEEKABLE), G_TYPE_BOOLEAN, seekable,
796 GST_QUARK (SEGMENT_START), G_TYPE_INT64, segment_start,
797 GST_QUARK (SEGMENT_END), G_TYPE_INT64, segment_end, NULL);
801 * gst_query_parse_seeking:
802 * @query: a GST_QUERY_SEEKING type query #GstQuery
803 * @format: (out) (allow-none): the format to set for the @segment_start
804 * and @segment_end values, or NULL
805 * @seekable: (out) (allow-none): the seekable flag to set, or NULL
806 * @segment_start: (out) (allow-none): the segment_start to set, or NULL
807 * @segment_end: (out) (allow-none): the segment_end to set, or NULL
809 * Parse a seeking query, writing the format into @format, and
810 * other results into the passed parameters, if the respective parameters
814 gst_query_parse_seeking (GstQuery * query, GstFormat * format,
815 gboolean * seekable, gint64 * segment_start, gint64 * segment_end)
817 GstStructure *structure;
819 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEEKING);
821 structure = GST_QUERY_STRUCTURE (query);
824 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
825 GST_QUARK (FORMAT)));
827 *seekable = g_value_get_boolean (gst_structure_id_get_value (structure,
828 GST_QUARK (SEEKABLE)));
830 *segment_start = g_value_get_int64 (gst_structure_id_get_value (structure,
831 GST_QUARK (SEGMENT_START)));
833 *segment_end = g_value_get_int64 (gst_structure_id_get_value (structure,
834 GST_QUARK (SEGMENT_END)));
838 ensure_array (GstStructure * s, GQuark quark, gsize element_size,
839 GDestroyNotify clear_func)
844 value = gst_structure_id_get_value (s, quark);
846 array = (GArray *) g_value_get_boxed (value);
848 GValue new_array_val = { 0, };
850 array = g_array_new (FALSE, TRUE, element_size);
852 g_array_set_clear_func (array, clear_func);
854 g_value_init (&new_array_val, G_TYPE_ARRAY);
855 g_value_take_boxed (&new_array_val, array);
857 gst_structure_id_take_value (s, quark, &new_array_val);
863 * gst_query_new_formats:
865 * Constructs a new query object for querying formats of
868 * Free-function: gst_query_unref
870 * Returns: (transfer full): a new #GstQuery
873 gst_query_new_formats (void)
876 GstStructure *structure;
878 structure = gst_structure_new_id_empty (GST_QUARK (QUERY_FORMATS));
879 query = gst_query_new_custom (GST_QUERY_FORMATS, structure);
885 gst_query_list_add_format (GValue * list, GstFormat format)
887 GValue item = { 0, };
889 g_value_init (&item, GST_TYPE_FORMAT);
890 g_value_set_enum (&item, format);
891 gst_value_list_append_value (list, &item);
892 g_value_unset (&item);
896 * gst_query_set_formats:
897 * @query: a #GstQuery
898 * @n_formats: the number of formats to set.
899 * @...: A number of @GstFormats equal to @n_formats.
901 * Set the formats query result fields in @query. The number of formats passed
902 * must be equal to @n_formats.
905 gst_query_set_formats (GstQuery * query, gint n_formats, ...)
908 GValue list = { 0, };
910 GstStructure *structure;
912 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
913 g_return_if_fail (gst_query_is_writable (query));
915 g_value_init (&list, GST_TYPE_LIST);
917 va_start (ap, n_formats);
918 for (i = 0; i < n_formats; i++) {
919 gst_query_list_add_format (&list, va_arg (ap, GstFormat));
923 structure = GST_QUERY_STRUCTURE (query);
924 gst_structure_set_value (structure, "formats", &list);
926 g_value_unset (&list);
931 * gst_query_set_formatsv:
932 * @query: a #GstQuery
933 * @n_formats: the number of formats to set.
934 * @formats: (in) (array length=n_formats): an array containing @n_formats
937 * Set the formats query result fields in @query. The number of formats passed
938 * in the @formats array must be equal to @n_formats.
941 gst_query_set_formatsv (GstQuery * query, gint n_formats,
942 const GstFormat * formats)
944 GValue list = { 0, };
946 GstStructure *structure;
948 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
949 g_return_if_fail (gst_query_is_writable (query));
951 g_value_init (&list, GST_TYPE_LIST);
952 for (i = 0; i < n_formats; i++) {
953 gst_query_list_add_format (&list, formats[i]);
955 structure = GST_QUERY_STRUCTURE (query);
956 gst_structure_set_value (structure, "formats", &list);
958 g_value_unset (&list);
962 * gst_query_parse_n_formats:
963 * @query: a #GstQuery
964 * @n_formats: (out) (allow-none): the number of formats in this query.
966 * Parse the number of formats in the formats @query.
969 gst_query_parse_n_formats (GstQuery * query, guint * n_formats)
971 GstStructure *structure;
973 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
978 structure = GST_QUERY_STRUCTURE (query);
979 list = gst_structure_get_value (structure, "formats");
983 *n_formats = gst_value_list_get_size (list);
988 * gst_query_parse_nth_format:
989 * @query: a #GstQuery
990 * @nth: (out): the nth format to retrieve.
991 * @format: (out) (allow-none): a pointer to store the nth format
993 * Parse the format query and retrieve the @nth format from it into
994 * @format. If the list contains less elements than @nth, @format will be
995 * set to GST_FORMAT_UNDEFINED.
998 gst_query_parse_nth_format (GstQuery * query, guint nth, GstFormat * format)
1000 GstStructure *structure;
1002 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
1007 structure = GST_QUERY_STRUCTURE (query);
1008 list = gst_structure_get_value (structure, "formats");
1010 *format = GST_FORMAT_UNDEFINED;
1012 if (nth < gst_value_list_get_size (list)) {
1014 (GstFormat) g_value_get_enum (gst_value_list_get_value (list, nth));
1016 *format = GST_FORMAT_UNDEFINED;
1022 * gst_query_new_buffering:
1023 * @format: the default #GstFormat for the new query
1025 * Constructs a new query object for querying the buffering status of
1028 * Free-function: gst_query_unref
1030 * Returns: (transfer full): a new #GstQuery
1033 gst_query_new_buffering (GstFormat format)
1036 GstStructure *structure;
1038 /* by default, we configure the answer as no buffering with a 100% buffering
1040 structure = gst_structure_new_id (GST_QUARK (QUERY_BUFFERING),
1041 GST_QUARK (BUSY), G_TYPE_BOOLEAN, FALSE,
1042 GST_QUARK (BUFFER_PERCENT), G_TYPE_INT, 100,
1043 GST_QUARK (BUFFERING_MODE), GST_TYPE_BUFFERING_MODE, GST_BUFFERING_STREAM,
1044 GST_QUARK (AVG_IN_RATE), G_TYPE_INT, -1,
1045 GST_QUARK (AVG_OUT_RATE), G_TYPE_INT, -1,
1046 GST_QUARK (BUFFERING_LEFT), G_TYPE_INT64, G_GINT64_CONSTANT (0),
1047 GST_QUARK (ESTIMATED_TOTAL), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
1048 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
1049 GST_QUARK (START_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
1050 GST_QUARK (STOP_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
1052 query = gst_query_new_custom (GST_QUERY_BUFFERING, structure);
1058 * gst_query_set_buffering_percent:
1059 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1060 * @busy: if buffering is busy
1061 * @percent: a buffering percent
1063 * Set the percentage of buffered data. This is a value between 0 and 100.
1064 * The @busy indicator is %TRUE when the buffering is in progress.
1067 gst_query_set_buffering_percent (GstQuery * query, gboolean busy, gint percent)
1069 GstStructure *structure;
1071 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1072 g_return_if_fail (gst_query_is_writable (query));
1073 g_return_if_fail (percent >= 0 && percent <= 100);
1075 structure = GST_QUERY_STRUCTURE (query);
1076 gst_structure_id_set (structure,
1077 GST_QUARK (BUSY), G_TYPE_BOOLEAN, busy,
1078 GST_QUARK (BUFFER_PERCENT), G_TYPE_INT, percent, NULL);
1082 * gst_query_parse_buffering_percent:
1083 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1084 * @busy: (out) (allow-none): if buffering is busy, or NULL
1085 * @percent: (out) (allow-none): a buffering percent, or NULL
1087 * Get the percentage of buffered data. This is a value between 0 and 100.
1088 * The @busy indicator is %TRUE when the buffering is in progress.
1091 gst_query_parse_buffering_percent (GstQuery * query, gboolean * busy,
1094 GstStructure *structure;
1096 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1098 structure = GST_QUERY_STRUCTURE (query);
1100 *busy = g_value_get_boolean (gst_structure_id_get_value (structure,
1103 *percent = g_value_get_int (gst_structure_id_get_value (structure,
1104 GST_QUARK (BUFFER_PERCENT)));
1108 * gst_query_set_buffering_stats:
1109 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1110 * @mode: a buffering mode
1111 * @avg_in: the average input rate
1112 * @avg_out: the average output rate
1113 * @buffering_left: amount of buffering time left in milliseconds
1115 * Configures the buffering stats values in @query.
1118 gst_query_set_buffering_stats (GstQuery * query, GstBufferingMode mode,
1119 gint avg_in, gint avg_out, gint64 buffering_left)
1121 GstStructure *structure;
1123 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1124 g_return_if_fail (gst_query_is_writable (query));
1126 structure = GST_QUERY_STRUCTURE (query);
1127 gst_structure_id_set (structure,
1128 GST_QUARK (BUFFERING_MODE), GST_TYPE_BUFFERING_MODE, mode,
1129 GST_QUARK (AVG_IN_RATE), G_TYPE_INT, avg_in,
1130 GST_QUARK (AVG_OUT_RATE), G_TYPE_INT, avg_out,
1131 GST_QUARK (BUFFERING_LEFT), G_TYPE_INT64, buffering_left, NULL);
1135 * gst_query_parse_buffering_stats:
1136 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1137 * @mode: (out) (allow-none): a buffering mode, or NULL
1138 * @avg_in: (out) (allow-none): the average input rate, or NULL
1139 * @avg_out: (out) (allow-none): the average output rat, or NULLe
1140 * @buffering_left: (out) (allow-none): amount of buffering time left in
1141 * milliseconds, or NULL
1143 * Extracts the buffering stats values from @query.
1146 gst_query_parse_buffering_stats (GstQuery * query,
1147 GstBufferingMode * mode, gint * avg_in, gint * avg_out,
1148 gint64 * buffering_left)
1150 GstStructure *structure;
1152 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1154 structure = GST_QUERY_STRUCTURE (query);
1156 *mode = (GstBufferingMode)
1157 g_value_get_enum (gst_structure_id_get_value (structure,
1158 GST_QUARK (BUFFERING_MODE)));
1160 *avg_in = g_value_get_int (gst_structure_id_get_value (structure,
1161 GST_QUARK (AVG_IN_RATE)));
1163 *avg_out = g_value_get_int (gst_structure_id_get_value (structure,
1164 GST_QUARK (AVG_OUT_RATE)));
1167 g_value_get_int64 (gst_structure_id_get_value (structure,
1168 GST_QUARK (BUFFERING_LEFT)));
1172 * gst_query_set_buffering_range:
1173 * @query: a #GstQuery
1174 * @format: the format to set for the @start and @stop values
1175 * @start: the start to set
1176 * @stop: the stop to set
1177 * @estimated_total: estimated total amount of download time
1179 * Set the available query result fields in @query.
1182 gst_query_set_buffering_range (GstQuery * query, GstFormat format,
1183 gint64 start, gint64 stop, gint64 estimated_total)
1185 GstStructure *structure;
1187 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1188 g_return_if_fail (gst_query_is_writable (query));
1190 structure = GST_QUERY_STRUCTURE (query);
1191 gst_structure_id_set (structure,
1192 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
1193 GST_QUARK (START_VALUE), G_TYPE_INT64, start,
1194 GST_QUARK (STOP_VALUE), G_TYPE_INT64, stop,
1195 GST_QUARK (ESTIMATED_TOTAL), G_TYPE_INT64, estimated_total, NULL);
1199 * gst_query_parse_buffering_range:
1200 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1201 * @format: (out) (allow-none): the format to set for the @segment_start
1202 * and @segment_end values, or NULL
1203 * @start: (out) (allow-none): the start to set, or NULL
1204 * @stop: (out) (allow-none): the stop to set, or NULL
1205 * @estimated_total: (out) (allow-none): estimated total amount of download
1208 * Parse an available query, writing the format into @format, and
1209 * other results into the passed parameters, if the respective parameters
1213 gst_query_parse_buffering_range (GstQuery * query, GstFormat * format,
1214 gint64 * start, gint64 * stop, gint64 * estimated_total)
1216 GstStructure *structure;
1218 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1220 structure = GST_QUERY_STRUCTURE (query);
1223 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
1224 GST_QUARK (FORMAT)));
1226 *start = g_value_get_int64 (gst_structure_id_get_value (structure,
1227 GST_QUARK (START_VALUE)));
1229 *stop = g_value_get_int64 (gst_structure_id_get_value (structure,
1230 GST_QUARK (STOP_VALUE)));
1231 if (estimated_total)
1233 g_value_get_int64 (gst_structure_id_get_value (structure,
1234 GST_QUARK (ESTIMATED_TOTAL)));
1237 /* GstQueryBufferingRange: internal struct for GArray */
1242 } GstQueryBufferingRange;
1245 * gst_query_add_buffering_range:
1246 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1247 * @start: start position of the range
1248 * @stop: stop position of the range
1250 * Set the buffering-ranges array field in @query. The current last
1251 * start position of the array should be inferior to @start.
1253 * Returns: a #gboolean indicating if the range was added or not.
1256 gst_query_add_buffering_range (GstQuery * query, gint64 start, gint64 stop)
1258 GstQueryBufferingRange range;
1259 GstStructure *structure;
1262 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING, FALSE);
1263 g_return_val_if_fail (gst_query_is_writable (query), FALSE);
1265 if (G_UNLIKELY (start >= stop))
1268 structure = GST_QUERY_STRUCTURE (query);
1269 array = ensure_array (structure, GST_QUARK (BUFFERING_RANGES),
1270 sizeof (GstQueryBufferingRange), NULL);
1272 if (array->len > 1) {
1273 GstQueryBufferingRange *last;
1275 last = &g_array_index (array, GstQueryBufferingRange, array->len - 1);
1277 if (G_UNLIKELY (start <= last->start))
1281 range.start = start;
1283 g_array_append_val (array, range);
1289 * gst_query_get_n_buffering_ranges:
1290 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1292 * Retrieve the number of values currently stored in the
1293 * buffered-ranges array of the query's structure.
1295 * Returns: the range array size as a #guint.
1298 gst_query_get_n_buffering_ranges (GstQuery * query)
1300 GstStructure *structure;
1303 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING, 0);
1305 structure = GST_QUERY_STRUCTURE (query);
1306 array = ensure_array (structure, GST_QUARK (BUFFERING_RANGES),
1307 sizeof (GstQueryBufferingRange), NULL);
1314 * gst_query_parse_nth_buffering_range:
1315 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1316 * @index: position in the buffered-ranges array to read
1317 * @start: (out) (allow-none): the start position to set, or NULL
1318 * @stop: (out) (allow-none): the stop position to set, or NULL
1320 * Parse an available query and get the start and stop values stored
1321 * at the @index of the buffered ranges array.
1323 * Returns: a #gboolean indicating if the parsing succeeded.
1326 gst_query_parse_nth_buffering_range (GstQuery * query, guint index,
1327 gint64 * start, gint64 * stop)
1329 GstQueryBufferingRange *range;
1330 GstStructure *structure;
1333 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING, FALSE);
1335 structure = GST_QUERY_STRUCTURE (query);
1337 array = ensure_array (structure, GST_QUARK (BUFFERING_RANGES),
1338 sizeof (GstQueryBufferingRange), NULL);
1339 g_return_val_if_fail (index < array->len, FALSE);
1341 range = &g_array_index (array, GstQueryBufferingRange, index);
1344 *start = range->start;
1346 *stop = range->stop;
1353 * gst_query_new_uri:
1355 * Constructs a new query URI query object. Use gst_query_unref()
1356 * when done with it. An URI query is used to query the current URI
1357 * that is used by the source or sink.
1359 * Free-function: gst_query_unref
1361 * Returns: (transfer full): a new #GstQuery
1364 gst_query_new_uri (void)
1367 GstStructure *structure;
1369 structure = gst_structure_new_id (GST_QUARK (QUERY_URI),
1370 GST_QUARK (URI), G_TYPE_STRING, NULL, NULL);
1372 query = gst_query_new_custom (GST_QUERY_URI, structure);
1378 * gst_query_set_uri:
1379 * @query: a #GstQuery with query type GST_QUERY_URI
1380 * @uri: the URI to set
1382 * Answer a URI query by setting the requested URI.
1385 gst_query_set_uri (GstQuery * query, const gchar * uri)
1387 GstStructure *structure;
1389 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
1390 g_return_if_fail (gst_query_is_writable (query));
1391 g_return_if_fail (gst_uri_is_valid (uri));
1393 structure = GST_QUERY_STRUCTURE (query);
1394 gst_structure_id_set (structure, GST_QUARK (URI), G_TYPE_STRING, uri, NULL);
1398 * gst_query_parse_uri:
1399 * @query: a #GstQuery
1400 * @uri: (out callee-allocates) (allow-none): the storage for the current URI
1403 * Parse an URI query, writing the URI into @uri as a newly
1404 * allocated string, if the respective parameters are non-NULL.
1405 * Free the string with g_free() after usage.
1408 gst_query_parse_uri (GstQuery * query, gchar ** uri)
1410 GstStructure *structure;
1412 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
1414 structure = GST_QUERY_STRUCTURE (query);
1416 *uri = g_value_dup_string (gst_structure_id_get_value (structure,
1421 * gst_query_new_allocation:
1422 * @caps: the negotiated caps
1423 * @need_pool: return a pool
1425 * Constructs a new query object for querying the allocation properties.
1427 * Free-function: gst_query_unref
1429 * Returns: (transfer full): a new #GstQuery
1432 gst_query_new_allocation (GstCaps * caps, gboolean need_pool)
1435 GstStructure *structure;
1437 structure = gst_structure_new_id (GST_QUARK (QUERY_ALLOCATION),
1438 GST_QUARK (CAPS), GST_TYPE_CAPS, caps,
1439 GST_QUARK (NEED_POOL), G_TYPE_BOOLEAN, need_pool, NULL);
1441 query = gst_query_new_custom (GST_QUERY_ALLOCATION, structure);
1447 * gst_query_parse_allocation:
1448 * @query: a #GstQuery
1449 * @caps: (out) (transfer none) (allow-none): The #GstCaps
1450 * @need_pool: (out) (allow-none): Whether a #GstBufferPool is needed
1452 * Parse an allocation query, writing the requested caps in @caps and
1453 * whether a pool is needed in @need_pool, if the respective parameters
1457 gst_query_parse_allocation (GstQuery * query, GstCaps ** caps,
1458 gboolean * need_pool)
1460 GstStructure *structure;
1462 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1464 structure = GST_QUERY_STRUCTURE (query);
1466 *caps = g_value_get_boxed (gst_structure_id_get_value (structure,
1469 gst_structure_id_get (structure,
1470 GST_QUARK (NEED_POOL), G_TYPE_BOOLEAN, need_pool, NULL);
1475 GstBufferPool *pool;
1482 allocation_pool_free (AllocationPool * ap)
1485 gst_object_unref (ap->pool);
1489 * gst_query_add_allocation_pool:
1490 * @query: A valid #GstQuery of type GST_QUERY_ALLOCATION.
1491 * @pool: the #GstBufferPool
1493 * @min_buffers: the min buffers
1494 * @max_buffers: the max buffers
1496 * Set the pool parameters in @query.
1499 gst_query_add_allocation_pool (GstQuery * query, GstBufferPool * pool,
1500 guint size, guint min_buffers, guint max_buffers)
1503 GstStructure *structure;
1506 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1507 g_return_if_fail (gst_query_is_writable (query));
1508 g_return_if_fail (size != 0);
1510 structure = GST_QUERY_STRUCTURE (query);
1511 array = ensure_array (structure, GST_QUARK (POOL),
1512 sizeof (AllocationPool), (GDestroyNotify) allocation_pool_free);
1514 if ((ap.pool = pool))
1515 gst_object_ref (pool);
1517 ap.min_buffers = min_buffers;
1518 ap.max_buffers = max_buffers;
1520 g_array_append_val (array, ap);
1525 * gst_query_get_n_allocation_pools:
1526 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1528 * Retrieve the number of values currently stored in the
1529 * pool array of the query's structure.
1531 * Returns: the pool array size as a #guint.
1534 gst_query_get_n_allocation_pools (GstQuery * query)
1537 GstStructure *structure;
1539 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION, 0);
1541 structure = GST_QUERY_STRUCTURE (query);
1542 array = ensure_array (structure, GST_QUARK (POOL),
1543 sizeof (AllocationPool), (GDestroyNotify) allocation_pool_free);
1549 * gst_query_parse_nth_allocation_pool:
1550 * @query: A valid #GstQuery of type GST_QUERY_ALLOCATION.
1551 * @index: index to parse
1552 * @pool: (out) (allow-none) (transfer full): the #GstBufferPool
1553 * @size: (out) (allow-none): the size
1554 * @min_buffers: (out) (allow-none): the min buffers
1555 * @max_buffers: (out) (allow-none): the max buffers
1557 * Get the pool parameters in @query.
1559 * Unref @pool with gst_object_unref() when it's not needed any more.
1562 gst_query_parse_nth_allocation_pool (GstQuery * query, guint index,
1563 GstBufferPool ** pool, guint * size, guint * min_buffers,
1564 guint * max_buffers)
1567 GstStructure *structure;
1570 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1572 structure = GST_QUERY_STRUCTURE (query);
1573 array = ensure_array (structure, GST_QUARK (POOL),
1574 sizeof (AllocationPool), (GDestroyNotify) allocation_pool_free);
1575 g_return_if_fail (index < array->len);
1577 ap = &g_array_index (array, AllocationPool, index);
1580 if ((*pool = ap->pool))
1581 gst_object_ref (*pool);
1585 *min_buffers = ap->min_buffers;
1587 *max_buffers = ap->max_buffers;
1591 * gst_query_set_nth_allocation_pool:
1592 * @index: index to modify
1593 * @query: A valid #GstQuery of type GST_QUERY_ALLOCATION.
1594 * @pool: the #GstBufferPool
1596 * @min_buffers: the min buffers
1597 * @max_buffers: the max buffers
1599 * Set the pool parameters in @query.
1602 gst_query_set_nth_allocation_pool (GstQuery * query, guint index,
1603 GstBufferPool * pool, guint size, guint min_buffers, guint max_buffers)
1606 GstStructure *structure;
1607 AllocationPool *oldap, ap;
1609 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1611 structure = GST_QUERY_STRUCTURE (query);
1612 array = ensure_array (structure, GST_QUARK (POOL),
1613 sizeof (AllocationPool), (GDestroyNotify) allocation_pool_free);
1614 g_return_if_fail (index < array->len);
1616 oldap = &g_array_index (array, AllocationPool, index);
1617 allocation_pool_free (oldap);
1619 if ((ap.pool = pool))
1620 gst_object_ref (pool);
1622 ap.min_buffers = min_buffers;
1623 ap.max_buffers = max_buffers;
1624 g_array_index (array, AllocationPool, index) = ap;
1628 * gst_query_remove_nth_allocation_pool:
1629 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1630 * @index: position in the allocation pool array to remove
1632 * Remove the allocation pool at @index of the allocation pool array.
1635 gst_query_remove_nth_allocation_pool (GstQuery * query, guint index)
1638 GstStructure *structure;
1640 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1641 g_return_if_fail (gst_query_is_writable (query));
1643 structure = GST_QUERY_STRUCTURE (query);
1645 ensure_array (structure, GST_QUARK (POOL), sizeof (AllocationPool),
1646 (GDestroyNotify) allocation_pool_free);
1647 g_return_if_fail (index < array->len);
1649 g_array_remove_index (array, index);
1655 GstStructure *params;
1659 allocation_meta_free (AllocationMeta * am)
1662 gst_structure_free (am->params);
1666 * gst_query_add_allocation_meta:
1667 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1668 * @api: the metadata API
1669 * @params: (transfer none) (allow-none): API specific parameters
1671 * Add @api with @params as one of the supported metadata API to @query.
1674 gst_query_add_allocation_meta (GstQuery * query, GType api,
1675 const GstStructure * params)
1678 GstStructure *structure;
1681 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1682 g_return_if_fail (api != 0);
1683 g_return_if_fail (gst_query_is_writable (query));
1685 structure = GST_QUERY_STRUCTURE (query);
1687 ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
1688 (GDestroyNotify) allocation_meta_free);
1691 am.params = (params ? gst_structure_copy (params) : NULL);
1693 g_array_append_val (array, am);
1697 * gst_query_get_n_allocation_metas:
1698 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1700 * Retrieve the number of values currently stored in the
1701 * meta API array of the query's structure.
1703 * Returns: the metadata API array size as a #guint.
1706 gst_query_get_n_allocation_metas (GstQuery * query)
1709 GstStructure *structure;
1711 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION, 0);
1713 structure = GST_QUERY_STRUCTURE (query);
1715 ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
1716 (GDestroyNotify) allocation_meta_free);
1722 * gst_query_parse_nth_allocation_meta:
1723 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1724 * @index: position in the metadata API array to read
1725 * @params: (out) (allow-none): API specific flags
1727 * Parse an available query and get the metadata API
1728 * at @index of the metadata API array.
1730 * Returns: a #GType of the metadata API at @index.
1733 gst_query_parse_nth_allocation_meta (GstQuery * query, guint index,
1734 const GstStructure ** params)
1737 GstStructure *structure;
1740 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION, 0);
1742 structure = GST_QUERY_STRUCTURE (query);
1744 ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
1745 (GDestroyNotify) allocation_meta_free);
1747 g_return_val_if_fail (index < array->len, 0);
1749 am = &g_array_index (array, AllocationMeta, index);
1752 *params = am->params;
1758 * gst_query_remove_nth_allocation_meta:
1759 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1760 * @index: position in the metadata API array to remove
1762 * Remove the metadata API at @index of the metadata API array.
1765 gst_query_remove_nth_allocation_meta (GstQuery * query, guint index)
1768 GstStructure *structure;
1770 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1771 g_return_if_fail (gst_query_is_writable (query));
1773 structure = GST_QUERY_STRUCTURE (query);
1775 ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
1776 (GDestroyNotify) allocation_meta_free);
1777 g_return_if_fail (index < array->len);
1779 g_array_remove_index (array, index);
1783 * gst_query_find_allocation_meta:
1784 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1785 * @api: the metadata API
1786 * @index: (out) (allow-none): the index
1788 * Check if @query has metadata @api set. When this function returns TRUE,
1789 * @index will contain the index where the requested API and the flags can be
1792 * Returns: TRUE when @api is in the list of metadata.
1795 gst_query_find_allocation_meta (GstQuery * query, GType api, guint * index)
1798 GstStructure *structure;
1801 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION, FALSE);
1802 g_return_val_if_fail (api != 0, FALSE);
1804 structure = GST_QUERY_STRUCTURE (query);
1806 ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
1807 (GDestroyNotify) allocation_meta_free);
1810 for (i = 0; i < len; i++) {
1811 AllocationMeta *am = &g_array_index (array, AllocationMeta, i);
1812 if (am->api == api) {
1823 GstAllocator *allocator;
1824 GstAllocationParams params;
1828 allocation_param_free (AllocationParam * ap)
1831 gst_object_unref (ap->allocator);
1835 * gst_query_add_allocation_param:
1836 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1837 * @allocator: (transfer none) (allow-none): the memory allocator
1838 * @params: (transfer none) (allow-none): a #GstAllocationParams
1840 * Add @allocator and its @params as a supported memory allocator.
1843 gst_query_add_allocation_param (GstQuery * query, GstAllocator * allocator,
1844 const GstAllocationParams * params)
1847 GstStructure *structure;
1850 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1851 g_return_if_fail (gst_query_is_writable (query));
1852 g_return_if_fail (allocator != NULL || params != NULL);
1854 structure = GST_QUERY_STRUCTURE (query);
1855 array = ensure_array (structure, GST_QUARK (ALLOCATOR),
1856 sizeof (AllocationParam), (GDestroyNotify) allocation_param_free);
1858 if ((ap.allocator = allocator))
1859 gst_object_ref (allocator);
1861 ap.params = *params;
1863 gst_allocation_params_init (&ap.params);
1865 g_array_append_val (array, ap);
1869 * gst_query_get_n_allocation_params:
1870 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1872 * Retrieve the number of values currently stored in the
1873 * allocator params array of the query's structure.
1875 * If no memory allocator is specified, the downstream element can handle
1876 * the default memory allocator. The first memory allocator in the query
1877 * should be generic and allow mapping to system memory, all following
1878 * allocators should be ordered by preference with the preferred one first.
1880 * Returns: the allocator array size as a #guint.
1883 gst_query_get_n_allocation_params (GstQuery * query)
1886 GstStructure *structure;
1888 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION, 0);
1890 structure = GST_QUERY_STRUCTURE (query);
1891 array = ensure_array (structure, GST_QUARK (ALLOCATOR),
1892 sizeof (AllocationParam), (GDestroyNotify) allocation_param_free);
1898 * gst_query_parse_nth_allocation_param:
1899 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1900 * @index: position in the allocator array to read
1901 * @allocator: (out) (transfer full) (allow-none): variable to hold the result
1902 * @params: (out) (allow-none): parameters for the allocator
1904 * Parse an available query and get the alloctor and its params
1905 * at @index of the allocator array.
1908 gst_query_parse_nth_allocation_param (GstQuery * query, guint index,
1909 GstAllocator ** allocator, GstAllocationParams * params)
1912 GstStructure *structure;
1913 AllocationParam *ap;
1915 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1917 structure = GST_QUERY_STRUCTURE (query);
1918 array = ensure_array (structure, GST_QUARK (ALLOCATOR),
1919 sizeof (AllocationParam), (GDestroyNotify) allocation_param_free);
1920 g_return_if_fail (index < array->len);
1922 ap = &g_array_index (array, AllocationParam, index);
1925 if ((*allocator = ap->allocator))
1926 gst_object_ref (*allocator);
1928 *params = ap->params;
1932 * gst_query_set_nth_allocation_param:
1933 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1934 * @index: position in the allocator array to set
1935 * @allocator: (transfer none) (allow-none): new allocator to set
1936 * @params: (transfer none) (allow-none): parameters for the allocator
1938 * Parse an available query and get the alloctor and its params
1939 * at @index of the allocator array.
1942 gst_query_set_nth_allocation_param (GstQuery * query, guint index,
1943 GstAllocator * allocator, const GstAllocationParams * params)
1946 GstStructure *structure;
1947 AllocationParam *old, ap;
1949 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1951 structure = GST_QUERY_STRUCTURE (query);
1952 array = ensure_array (structure, GST_QUARK (ALLOCATOR),
1953 sizeof (AllocationParam), (GDestroyNotify) allocation_param_free);
1954 g_return_if_fail (index < array->len);
1956 old = &g_array_index (array, AllocationParam, index);
1957 allocation_param_free (old);
1959 if ((ap.allocator = allocator))
1960 gst_object_ref (allocator);
1962 ap.params = *params;
1964 gst_allocation_params_init (&ap.params);
1966 g_array_index (array, AllocationParam, index) = ap;
1970 * gst_query_remove_nth_allocation_param:
1971 * @query: a GST_QUERY_ALLOCATION type query #GstQuery
1972 * @index: position in the allocation param array to remove
1974 * Remove the allocation param at @index of the allocation param array.
1977 gst_query_remove_nth_allocation_param (GstQuery * query, guint index)
1980 GstStructure *structure;
1982 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
1983 g_return_if_fail (gst_query_is_writable (query));
1985 structure = GST_QUERY_STRUCTURE (query);
1987 ensure_array (structure, GST_QUARK (ALLOCATOR), sizeof (AllocationParam),
1988 (GDestroyNotify) allocation_param_free);
1989 g_return_if_fail (index < array->len);
1991 g_array_remove_index (array, index);
1995 * gst_query_new_scheduling:
1997 * Constructs a new query object for querying the scheduling properties.
1999 * Free-function: gst_query_unref
2001 * Returns: (transfer full): a new #GstQuery
2004 gst_query_new_scheduling (void)
2007 GstStructure *structure;
2009 structure = gst_structure_new_id (GST_QUARK (QUERY_SCHEDULING),
2010 GST_QUARK (FLAGS), GST_TYPE_SCHEDULING_FLAGS, 0,
2011 GST_QUARK (MINSIZE), G_TYPE_INT, 1,
2012 GST_QUARK (MAXSIZE), G_TYPE_INT, -1,
2013 GST_QUARK (ALIGN), G_TYPE_INT, 0, NULL);
2014 query = gst_query_new_custom (GST_QUERY_SCHEDULING, structure);
2020 * gst_query_set_scheduling:
2021 * @query: A valid #GstQuery of type GST_QUERY_SCHEDULING.
2022 * @flags: #GstSchedulingFlags
2023 * @minsize: the suggested minimum size of pull requests
2024 * @maxsize: the suggested maximum size of pull requests
2025 * @align: the suggested alignment of pull requests
2027 * Set the scheduling properties.
2030 gst_query_set_scheduling (GstQuery * query, GstSchedulingFlags flags,
2031 gint minsize, gint maxsize, gint align)
2033 GstStructure *structure;
2035 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING);
2036 g_return_if_fail (gst_query_is_writable (query));
2038 structure = GST_QUERY_STRUCTURE (query);
2039 gst_structure_id_set (structure,
2040 GST_QUARK (FLAGS), GST_TYPE_SCHEDULING_FLAGS, flags,
2041 GST_QUARK (MINSIZE), G_TYPE_INT, minsize,
2042 GST_QUARK (MAXSIZE), G_TYPE_INT, maxsize,
2043 GST_QUARK (ALIGN), G_TYPE_INT, align, NULL);
2047 * gst_query_parse_scheduling:
2048 * @query: A valid #GstQuery of type GST_QUERY_SCHEDULING.
2049 * @flags: (out) (allow-none): #GstSchedulingFlags
2050 * @minsize: (out) (allow-none): the suggested minimum size of pull requests
2051 * @maxsize: (out) (allow-none): the suggested maximum size of pull requests:
2052 * @align: (out) (allow-none): the suggested alignment of pull requests
2054 * Set the scheduling properties.
2057 gst_query_parse_scheduling (GstQuery * query, GstSchedulingFlags * flags,
2058 gint * minsize, gint * maxsize, gint * align)
2060 GstStructure *structure;
2062 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING);
2064 structure = GST_QUERY_STRUCTURE (query);
2065 gst_structure_id_get (structure,
2066 GST_QUARK (FLAGS), GST_TYPE_SCHEDULING_FLAGS, flags,
2067 GST_QUARK (MINSIZE), G_TYPE_INT, minsize,
2068 GST_QUARK (MAXSIZE), G_TYPE_INT, maxsize,
2069 GST_QUARK (ALIGN), G_TYPE_INT, align, NULL);
2073 * gst_query_add_scheduling_mode:
2074 * @query: a GST_QUERY_SCHEDULING type query #GstQuery
2075 * @mode: a #GstPadMode
2077 * Add @mode as aone of the supported scheduling modes to @query.
2080 gst_query_add_scheduling_mode (GstQuery * query, GstPadMode mode)
2082 GstStructure *structure;
2085 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING);
2086 g_return_if_fail (gst_query_is_writable (query));
2088 structure = GST_QUERY_STRUCTURE (query);
2090 ensure_array (structure, GST_QUARK (MODES), sizeof (GstPadMode), NULL);
2092 g_array_append_val (array, mode);
2096 * gst_query_get_n_scheduling_modes:
2097 * @query: a GST_QUERY_SCHEDULING type query #GstQuery
2099 * Retrieve the number of values currently stored in the
2100 * scheduling mode array of the query's structure.
2102 * Returns: the scheduling mode array size as a #guint.
2105 gst_query_get_n_scheduling_modes (GstQuery * query)
2108 GstStructure *structure;
2110 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING, 0);
2112 structure = GST_QUERY_STRUCTURE (query);
2114 ensure_array (structure, GST_QUARK (MODES), sizeof (GstPadMode), NULL);
2120 * gst_query_parse_nth_scheduling_mode:
2121 * @query: a GST_QUERY_SCHEDULING type query #GstQuery
2122 * @index: position in the scheduling modes array to read
2124 * Parse an available query and get the scheduling mode
2125 * at @index of the scheduling modes array.
2127 * Returns: a #GstPadMode of the scheduling mode at @index.
2130 gst_query_parse_nth_scheduling_mode (GstQuery * query, guint index)
2132 GstStructure *structure;
2135 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING,
2138 structure = GST_QUERY_STRUCTURE (query);
2140 ensure_array (structure, GST_QUARK (MODES), sizeof (GstPadMode), NULL);
2141 g_return_val_if_fail (index < array->len, GST_PAD_MODE_NONE);
2143 return g_array_index (array, GstPadMode, index);
2147 * gst_query_has_scheduling_mode:
2148 * @query: a GST_QUERY_SCHEDULING type query #GstQuery
2149 * @mode: the scheduling mode
2151 * Check if @query has scheduling mode set.
2155 * When checking if upstream supports pull mode, it is usually not
2156 * enough to just check for GST_PAD_MODE_PULL with this function, you
2157 * also want to check whether the scheduling flags returned by
2158 * gst_query_parse_scheduling() have the seeking flag set (meaning
2159 * random access is supported, not only sequential pulls).
2163 * Returns: TRUE when @mode is in the list of scheduling modes.
2166 gst_query_has_scheduling_mode (GstQuery * query, GstPadMode mode)
2168 GstStructure *structure;
2172 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING, FALSE);
2174 structure = GST_QUERY_STRUCTURE (query);
2176 ensure_array (structure, GST_QUARK (MODES), sizeof (GstPadMode), NULL);
2179 for (i = 0; i < len; i++) {
2180 if (mode == g_array_index (array, GstPadMode, i))
2187 * gst_query_has_scheduling_mode_with_flags:
2188 * @query: a GST_QUERY_SCHEDULING type query #GstQuery
2189 * @mode: the scheduling mode
2190 * @flags: #GstSchedulingFlags
2192 * Check if @query has scheduling mode set and @flags is set in
2193 * query scheduling flags.
2195 * Returns: TRUE when @mode is in the list of scheduling modes
2196 * and @flags are compatible with query flags.
2199 gst_query_has_scheduling_mode_with_flags (GstQuery * query, GstPadMode mode,
2200 GstSchedulingFlags flags)
2202 GstSchedulingFlags sched_flags;
2204 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING, FALSE);
2206 gst_query_parse_scheduling (query, &sched_flags, NULL, NULL, NULL);
2208 return ((flags & sched_flags) == flags) &&
2209 gst_query_has_scheduling_mode (query, mode);
2213 * gst_query_new_accept_caps:
2214 * @caps: a fixed #GstCaps
2216 * Constructs a new query object for querying if @caps are accepted.
2218 * Free-function: gst_query_unref
2220 * Returns: (transfer full): a new #GstQuery
2223 gst_query_new_accept_caps (GstCaps * caps)
2226 GstStructure *structure;
2228 g_return_val_if_fail (gst_caps_is_fixed (caps), NULL);
2230 structure = gst_structure_new_id (GST_QUARK (QUERY_ACCEPT_CAPS),
2231 GST_QUARK (CAPS), GST_TYPE_CAPS, caps,
2232 GST_QUARK (RESULT), G_TYPE_BOOLEAN, FALSE, NULL);
2233 query = gst_query_new_custom (GST_QUERY_ACCEPT_CAPS, structure);
2239 * gst_query_parse_accept_caps:
2240 * @query: The query to parse
2241 * @caps: (out): A pointer to the caps
2243 * Get the caps from @query. The caps remains valid as long as @query remains
2247 gst_query_parse_accept_caps (GstQuery * query, GstCaps ** caps)
2249 GstStructure *structure;
2251 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ACCEPT_CAPS);
2252 g_return_if_fail (caps != NULL);
2254 structure = GST_QUERY_STRUCTURE (query);
2255 *caps = g_value_get_boxed (gst_structure_id_get_value (structure,
2260 * gst_query_set_accept_caps_result:
2261 * @query: a GST_QUERY_ACCEPT_CAPS type query #GstQuery
2262 * @result: the result to set
2264 * Set @result as the result for the @query.
2267 gst_query_set_accept_caps_result (GstQuery * query, gboolean result)
2269 GstStructure *structure;
2271 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ACCEPT_CAPS);
2272 g_return_if_fail (gst_query_is_writable (query));
2274 structure = GST_QUERY_STRUCTURE (query);
2275 gst_structure_id_set (structure,
2276 GST_QUARK (RESULT), G_TYPE_BOOLEAN, result, NULL);
2280 * gst_query_parse_accept_caps_result:
2281 * @query: a GST_QUERY_ACCEPT_CAPS type query #GstQuery
2282 * @result: location for the result
2284 * Parse the result from @query and store in @result.
2287 gst_query_parse_accept_caps_result (GstQuery * query, gboolean * result)
2289 GstStructure *structure;
2291 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ACCEPT_CAPS);
2293 structure = GST_QUERY_STRUCTURE (query);
2294 gst_structure_id_get (structure,
2295 GST_QUARK (RESULT), G_TYPE_BOOLEAN, result, NULL);
2299 * gst_query_new_caps:
2302 * Constructs a new query object for querying the caps.
2304 * The CAPS query should return the allowable caps for a pad in the context
2305 * of the element's state, its link to other elements, and the devices or files
2306 * it has opened. These caps must be a subset of the pad template caps. In the
2307 * NULL state with no links, the CAPS query should ideally return the same caps
2308 * as the pad template. In rare circumstances, an object property can affect
2309 * the caps returned by the CAPS query, but this is discouraged.
2311 * For most filters, the caps returned by CAPS query is directly affected by the
2312 * allowed caps on other pads. For demuxers and decoders, the caps returned by
2313 * the srcpad's getcaps function is directly related to the stream data. Again,
2314 * the CAPS query should return the most specific caps it reasonably can, since this
2315 * helps with autoplugging.
2317 * The @filter is used to restrict the result caps, only the caps matching
2318 * @filter should be returned from the CAPS query. Specifying a filter might
2319 * greatly reduce the amount of processing an element needs to do.
2321 * Free-function: gst_query_unref
2323 * Returns: (transfer full): a new #GstQuery
2326 gst_query_new_caps (GstCaps * filter)
2329 GstStructure *structure;
2331 structure = gst_structure_new_id (GST_QUARK (QUERY_CAPS),
2332 GST_QUARK (FILTER), GST_TYPE_CAPS, filter,
2333 GST_QUARK (CAPS), GST_TYPE_CAPS, NULL, NULL);
2334 query = gst_query_new_custom (GST_QUERY_CAPS, structure);
2340 * gst_query_parse_caps:
2341 * @query: The query to parse
2342 * @filter: (out): A pointer to the caps filter
2344 * Get the filter from the caps @query. The caps remains valid as long as
2345 * @query remains valid.
2348 gst_query_parse_caps (GstQuery * query, GstCaps ** filter)
2350 GstStructure *structure;
2352 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CAPS);
2353 g_return_if_fail (filter != NULL);
2355 structure = GST_QUERY_STRUCTURE (query);
2356 *filter = g_value_get_boxed (gst_structure_id_get_value (structure,
2357 GST_QUARK (FILTER)));
2361 * gst_query_set_caps_result:
2362 * @query: The query to use
2363 * @caps: (in): A pointer to the caps
2365 * Set the @caps result in @query.
2368 gst_query_set_caps_result (GstQuery * query, GstCaps * caps)
2370 GstStructure *structure;
2372 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CAPS);
2373 g_return_if_fail (gst_query_is_writable (query));
2375 structure = GST_QUERY_STRUCTURE (query);
2376 gst_structure_id_set (structure, GST_QUARK (CAPS), GST_TYPE_CAPS, caps, NULL);
2380 * gst_query_parse_caps_result:
2381 * @query: The query to parse
2382 * @caps: (out): A pointer to the caps
2384 * Get the caps result from @query. The caps remains valid as long as
2385 * @query remains valid.
2388 gst_query_parse_caps_result (GstQuery * query, GstCaps ** caps)
2390 GstStructure *structure;
2392 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CAPS);
2393 g_return_if_fail (caps != NULL);
2395 structure = GST_QUERY_STRUCTURE (query);
2396 *caps = g_value_get_boxed (gst_structure_id_get_value (structure,
2402 gst_query_intersect_caps_result (GstQuery * query, GstCaps * filter,
2403 GstCapsIntersectMode mode)
2405 GstCaps *res, *caps = NULL;
2407 gst_query_parse_caps_result (query, &caps);
2408 res = gst_caps_intersect_full (filter, caps, GST_CAPS_INTERSECT_FIRST);
2409 gst_query_set_caps_result (query, res);
2410 gst_caps_unref (res);
2415 * gst_query_new_drain:
2417 * Constructs a new query object for querying the drain state.
2419 * Free-function: gst_query_unref
2421 * Returns: (transfer full): a new #GstQuery
2424 gst_query_new_drain (void)
2427 GstStructure *structure;
2429 structure = gst_structure_new_id_empty (GST_QUARK (QUERY_DRAIN));
2430 query = gst_query_new_custom (GST_QUERY_DRAIN, structure);
2436 * gst_query_new_context:
2438 * Constructs a new query object for querying the pipeline-local context.
2440 * Free-function: gst_query_unref
2442 * Returns: (transfer full): a new #GstQuery
2445 gst_query_new_context (void)
2448 GstStructure *structure;
2450 structure = gst_structure_new_id_empty (GST_QUARK (QUERY_CONTEXT));
2451 query = gst_query_new_custom (GST_QUERY_CONTEXT, structure);
2457 * gst_query_set_context:
2458 * @query: a #GstQuery with query type GST_QUERY_CONTEXT
2459 * @context: the requested #GstContext
2461 * Answer a context query by setting the requested context.
2464 gst_query_set_context (GstQuery * query, GstContext * context)
2468 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT);
2470 s = GST_QUERY_STRUCTURE (query);
2472 gst_structure_id_set (s,
2473 GST_QUARK (CONTEXT), GST_TYPE_CONTEXT, context, NULL);
2477 * gst_query_parse_context:
2478 * @query: The query to parse
2479 * @context: (out): A pointer to store the #GstContext
2481 * Get the context from the context @query. The context remains valid as long as
2482 * @query remains valid.
2485 gst_query_parse_context (GstQuery * query, GstContext ** context)
2487 GstStructure *structure;
2489 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT);
2490 g_return_if_fail (context != NULL);
2492 structure = GST_QUERY_STRUCTURE (query);
2493 *context = g_value_get_boxed (gst_structure_id_get_value (structure,
2494 GST_QUARK (CONTEXT)));
2498 free_array_string (gpointer ptr)
2500 gchar *str = *(gchar **) ptr;
2505 * gst_query_add_context_type:
2506 * @query: a GST_QUERY_NEED_CONTEXT type query
2507 * @context_type: a context type
2509 * Add a new context type to @query.
2512 gst_query_add_context_type (GstQuery * query, const gchar * context_type)
2514 GstStructure *structure;
2518 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT);
2519 g_return_if_fail (gst_query_is_writable (query));
2521 structure = GST_QUERY_STRUCTURE (query);
2522 array = ensure_array (structure, GST_QUARK (CONTEXT_TYPES),
2523 sizeof (gchar *), free_array_string);
2525 copy = g_strdup (context_type);
2526 g_array_append_val (array, copy);
2530 * gst_query_get_n_context_types:
2531 * @query: a GST_QUERY_NEED_CONTEXT type query
2533 * Retrieve the number of values currently stored in the
2534 * context-types array of the query's structure.
2536 * Returns: the context-types array size as a #guint.
2539 gst_query_get_n_context_types (GstQuery * query)
2541 GstStructure *structure;
2544 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT, 0);
2546 structure = GST_QUERY_STRUCTURE (query);
2547 array = ensure_array (structure, GST_QUARK (CONTEXT_TYPES),
2548 sizeof (gchar *), free_array_string);
2554 * gst_query_parse_nth_context_type:
2555 * @query: a GST_QUERY_NEED_CONTEXT type query
2556 * @context_type: (out) (allow-none): the context type, or NULL
2558 * Parse a context type from an existing GST_QUERY_NEED_CONTEXT query
2561 * Returns: a #gboolean indicating if the parsing succeeded.
2564 gst_query_parse_nth_context_type (GstQuery * query, guint index,
2565 const gchar ** context_type)
2567 GstStructure *structure;
2570 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT, FALSE);
2572 structure = GST_QUERY_STRUCTURE (query);
2574 array = ensure_array (structure, GST_QUARK (CONTEXT_TYPES),
2575 sizeof (gchar *), free_array_string);
2576 g_return_val_if_fail (index < array->len, FALSE);
2579 *context_type = g_array_index (array, gchar *, index);