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., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
26 * @short_description: Dynamically register new query types. Provide functions
27 * to create queries, and to set and parse values in them.
28 * @see_also: #GstPad, #GstElement
30 * GstQuery functions are used to register new query types to the gstreamer
32 * Queries can be performed on pads (gst_pad_query()) and elements
33 * (gst_element_query()). Please note that some queries might need a running
36 * Queries can be created using the gst_query_new_*() functions.
37 * Query values can be set using gst_query_set_*(), and parsed using
38 * gst_query_parse_*() helpers.
40 * The following example shows how to query the duration of a pipeline:
43 * <title>Query duration on a pipeline</title>
47 * query = gst_query_new_duration (GST_FORMAT_TIME);
48 * res = gst_element_query (pipeline, query);
51 * gst_query_parse_duration (query, NULL, &duration);
52 * g_print ("duration = %"GST_TIME_FORMAT, GST_TIME_ARGS (duration));
55 * g_print ("duration query failed...");
57 * gst_query_unref (query);
61 * Last reviewed on 2006-02-14 (0.10.4)
64 #include "gst_private.h"
68 #include "gstenumtypes.h"
72 GST_DEBUG_CATEGORY_STATIC (gst_query_debug);
73 #define GST_CAT_DEFAULT gst_query_debug
75 static void gst_query_finalize (GstQuery * query);
76 static GstQuery *_gst_query_copy (GstQuery * query);
78 static GStaticMutex mutex = G_STATIC_MUTEX_INIT;
79 static GList *_gst_queries = NULL;
80 static GHashTable *_nick_to_query = NULL;
81 static GHashTable *_query_type_to_nick = NULL;
82 static guint32 _n_values = 1; /* we start from 1 because 0 reserved for NONE */
84 static GstMiniObjectClass *parent_class = NULL;
86 static GstQueryTypeDefinition standard_definitions[] = {
87 {GST_QUERY_POSITION, "position", "Current position", 0},
88 {GST_QUERY_DURATION, "duration", "Total duration", 0},
89 {GST_QUERY_LATENCY, "latency", "Latency", 0},
90 {GST_QUERY_JITTER, "jitter", "Jitter", 0},
91 {GST_QUERY_RATE, "rate", "Configured rate 1000000 = 1", 0},
92 {GST_QUERY_SEEKING, "seeking", "Seeking capabilities and parameters", 0},
93 {GST_QUERY_SEGMENT, "segment", "currently configured segment", 0},
94 {GST_QUERY_CONVERT, "convert", "Converting between formats", 0},
95 {GST_QUERY_FORMATS, "formats", "Supported formats for conversion", 0},
96 {GST_QUERY_BUFFERING, "buffering", "Buffering status", 0},
97 {GST_QUERY_CUSTOM, "custom", "Custom query", 0},
98 {GST_QUERY_URI, "uri", "URI of the source or sink", 0},
99 {GST_QUERY_NONE, NULL, NULL, 0}
103 _gst_query_initialize (void)
105 GstQueryTypeDefinition *standards = standard_definitions;
107 GST_CAT_INFO (GST_CAT_GST_INIT, "init queries");
109 GST_DEBUG_CATEGORY_INIT (gst_query_debug, "query", 0, "query system");
111 g_static_mutex_lock (&mutex);
112 if (_nick_to_query == NULL) {
113 _nick_to_query = g_hash_table_new (g_str_hash, g_str_equal);
114 _query_type_to_nick = g_hash_table_new (NULL, NULL);
117 while (standards->nick) {
118 standards->quark = g_quark_from_static_string (standards->nick);
119 g_hash_table_insert (_nick_to_query, (gpointer) standards->nick, standards);
120 g_hash_table_insert (_query_type_to_nick,
121 GINT_TO_POINTER (standards->value), standards);
123 _gst_queries = g_list_append (_gst_queries, standards);
127 g_static_mutex_unlock (&mutex);
129 g_type_class_ref (gst_query_get_type ());
133 * gst_query_type_get_name:
134 * @query: the query type
136 * Get a printable name for the given query type. Do not modify or free.
138 * Returns: a reference to the static name of the query.
141 gst_query_type_get_name (GstQueryType query)
143 const GstQueryTypeDefinition *def;
145 def = gst_query_type_get_details (query);
151 * gst_query_type_to_quark:
152 * @query: the query type
154 * Get the unique quark for the given query type.
156 * Returns: the quark associated with the query type
159 gst_query_type_to_quark (GstQueryType query)
161 const GstQueryTypeDefinition *def;
163 def = gst_query_type_get_details (query);
168 G_DEFINE_TYPE (GstQuery, gst_query, GST_TYPE_MINI_OBJECT);
171 gst_query_class_init (GstQueryClass * klass)
173 parent_class = g_type_class_peek_parent (klass);
175 klass->mini_object_class.copy = (GstMiniObjectCopyFunction) _gst_query_copy;
176 klass->mini_object_class.finalize =
177 (GstMiniObjectFinalizeFunction) gst_query_finalize;
182 gst_query_init (GstQuery * query)
187 gst_query_finalize (GstQuery * query)
189 g_return_if_fail (query != NULL);
191 if (query->structure) {
192 gst_structure_set_parent_refcount (query->structure, NULL);
193 gst_structure_free (query->structure);
196 /* GST_MINI_OBJECT_CLASS (parent_class)->finalize (GST_MINI_OBJECT (query)); */
200 _gst_query_copy (GstQuery * query)
204 copy = (GstQuery *) gst_mini_object_new (GST_TYPE_QUERY);
206 copy->type = query->type;
208 if (query->structure) {
209 copy->structure = gst_structure_copy (query->structure);
210 gst_structure_set_parent_refcount (copy->structure,
211 &query->mini_object.refcount);
220 * gst_query_type_register:
221 * @nick: The nick of the new query
222 * @description: The description of the new query
224 * Create a new GstQueryType based on the nick or return an
225 * already registered query with that nick
227 * Returns: A new GstQueryType or an already registered query
228 * with the same nick.
231 gst_query_type_register (const gchar * nick, const gchar * description)
233 GstQueryTypeDefinition *query;
236 g_return_val_if_fail (nick != NULL, GST_QUERY_NONE);
237 g_return_val_if_fail (description != NULL, GST_QUERY_NONE);
239 lookup = gst_query_type_get_by_nick (nick);
240 if (lookup != GST_QUERY_NONE)
243 query = g_slice_new (GstQueryTypeDefinition);
244 query->value = (GstQueryType) _n_values;
245 query->nick = g_strdup (nick);
246 query->description = g_strdup (description);
247 query->quark = g_quark_from_static_string (query->nick);
249 g_static_mutex_lock (&mutex);
250 g_hash_table_insert (_nick_to_query, (gpointer) query->nick, query);
251 g_hash_table_insert (_query_type_to_nick, GINT_TO_POINTER (query->value),
253 _gst_queries = g_list_append (_gst_queries, query);
255 g_static_mutex_unlock (&mutex);
261 * gst_query_type_get_by_nick:
262 * @nick: The nick of the query
264 * Get the query type registered with @nick.
266 * Returns: The query registered with @nick or #GST_QUERY_NONE
267 * if the query was not registered.
270 gst_query_type_get_by_nick (const gchar * nick)
272 GstQueryTypeDefinition *query;
274 g_return_val_if_fail (nick != NULL, GST_QUERY_NONE);
276 g_static_mutex_lock (&mutex);
277 query = g_hash_table_lookup (_nick_to_query, nick);
278 g_static_mutex_unlock (&mutex);
283 return GST_QUERY_NONE;
287 * gst_query_types_contains:
288 * @types: The query array to search
289 * @type: the #GstQueryType to find
291 * See if the given #GstQueryType is inside the @types query types array.
293 * Returns: TRUE if the type is found inside the array
296 gst_query_types_contains (const GstQueryType * types, GstQueryType type)
312 * gst_query_type_get_details:
313 * @type: a #GstQueryType
315 * Get details about the given #GstQueryType.
317 * Returns: The #GstQueryTypeDefinition for @type or NULL on failure.
319 const GstQueryTypeDefinition *
320 gst_query_type_get_details (GstQueryType type)
322 const GstQueryTypeDefinition *result;
324 g_static_mutex_lock (&mutex);
325 result = g_hash_table_lookup (_query_type_to_nick, GINT_TO_POINTER (type));
326 g_static_mutex_unlock (&mutex);
332 * gst_query_type_iterate_definitions:
334 * Get a #GstIterator of all the registered query types. The definitions
335 * iterated over are read only.
337 * Free-function: gst_iterator_free
339 * Returns: (transfer full): a #GstIterator of #GstQueryTypeDefinition.
342 gst_query_type_iterate_definitions (void)
346 g_static_mutex_lock (&mutex);
347 /* FIXME: register a boxed type for GstQueryTypeDefinition */
348 result = gst_iterator_new_list (G_TYPE_POINTER,
349 g_static_mutex_get_mutex (&mutex), &_n_values, &_gst_queries,
351 g_static_mutex_unlock (&mutex);
357 gst_query_new (GstQueryType type, GstStructure * structure)
361 query = (GstQuery *) gst_mini_object_new (GST_TYPE_QUERY);
363 GST_DEBUG ("creating new query %p %s", query, gst_query_type_get_name (type));
368 query->structure = structure;
369 gst_structure_set_parent_refcount (query->structure,
370 &query->mini_object.refcount);
372 query->structure = NULL;
379 * gst_query_new_position:
380 * @format: the default #GstFormat for the new query
382 * Constructs a new query stream position query object. Use gst_query_unref()
383 * when done with it. A position query is used to query the current position
384 * of playback in the streams, in some format.
386 * Free-function: gst_query_unref
388 * Returns: (transfer full): a new #GstQuery
391 gst_query_new_position (GstFormat format)
394 GstStructure *structure;
396 structure = gst_structure_id_new (GST_QUARK (QUERY_POSITION),
397 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
398 GST_QUARK (CURRENT), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
400 query = gst_query_new (GST_QUERY_POSITION, structure);
406 * gst_query_set_position:
407 * @query: a #GstQuery with query type GST_QUERY_POSITION
408 * @format: the requested #GstFormat
409 * @cur: the position to set
411 * Answer a position query by setting the requested value in the given format.
414 gst_query_set_position (GstQuery * query, GstFormat format, gint64 cur)
416 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_POSITION);
418 gst_structure_id_set (query->structure,
419 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
420 GST_QUARK (CURRENT), G_TYPE_INT64, cur, NULL);
424 * gst_query_parse_position:
425 * @query: a #GstQuery
426 * @format: (out) (allow-none): the storage for the #GstFormat of the
427 * position values (may be NULL)
428 * @cur: (out) (allow-none): the storage for the current position (may be NULL)
430 * Parse a position query, writing the format into @format, and the position
431 * into @cur, if the respective parameters are non-NULL.
434 gst_query_parse_position (GstQuery * query, GstFormat * format, gint64 * cur)
436 GstStructure *structure;
438 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_POSITION);
440 structure = query->structure;
443 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
444 GST_QUARK (FORMAT)));
446 *cur = g_value_get_int64 (gst_structure_id_get_value (structure,
447 GST_QUARK (CURRENT)));
452 * gst_query_new_duration:
453 * @format: the #GstFormat for this duration query
455 * Constructs a new stream duration query object to query in the given format.
456 * Use gst_query_unref() when done with it. A duration query will give the
457 * total length of the stream.
459 * Free-function: gst_query_unref
461 * Returns: (transfer full): a new #GstQuery
464 gst_query_new_duration (GstFormat format)
467 GstStructure *structure;
469 structure = gst_structure_id_new (GST_QUARK (QUERY_DURATION),
470 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
471 GST_QUARK (DURATION), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
473 query = gst_query_new (GST_QUERY_DURATION, structure);
479 * gst_query_set_duration:
480 * @query: a #GstQuery
481 * @format: the #GstFormat for the duration
482 * @duration: the duration of the stream
484 * Answer a duration query by setting the requested value in the given format.
487 gst_query_set_duration (GstQuery * query, GstFormat format, gint64 duration)
489 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_DURATION);
491 gst_structure_id_set (query->structure,
492 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
493 GST_QUARK (DURATION), G_TYPE_INT64, duration, NULL);
497 * gst_query_parse_duration:
498 * @query: a #GstQuery
499 * @format: (out) (allow-none): the storage for the #GstFormat of the duration
501 * @duration: (out) (allow-none): the storage for the total duration, or NULL.
503 * Parse a duration query answer. Write the format of the duration into @format,
504 * and the value into @duration, if the respective variables are non-NULL.
507 gst_query_parse_duration (GstQuery * query, GstFormat * format,
510 GstStructure *structure;
512 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_DURATION);
514 structure = query->structure;
517 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
518 GST_QUARK (FORMAT)));
520 *duration = g_value_get_int64 (gst_structure_id_get_value (structure,
521 GST_QUARK (DURATION)));
525 * gst_query_new_latency:
527 * Constructs a new latency query object.
528 * Use gst_query_unref() when done with it. A latency query is usually performed
529 * by sinks to compensate for additional latency introduced by elements in the
532 * Free-function: gst_query_unref
534 * Returns: (transfer full): a #GstQuery
539 gst_query_new_latency (void)
542 GstStructure *structure;
544 structure = gst_structure_id_new (GST_QUARK (QUERY_LATENCY),
545 GST_QUARK (LIVE), G_TYPE_BOOLEAN, FALSE,
546 GST_QUARK (MIN_LATENCY), G_TYPE_UINT64, G_GUINT64_CONSTANT (0),
547 GST_QUARK (MAX_LATENCY), G_TYPE_UINT64, G_GUINT64_CONSTANT (-1), NULL);
549 query = gst_query_new (GST_QUERY_LATENCY, structure);
555 * gst_query_set_latency:
556 * @query: a #GstQuery
557 * @live: if there is a live element upstream
558 * @min_latency: the minimal latency of the live element
559 * @max_latency: the maximal latency of the live element
561 * Answer a latency query by setting the requested values in the given format.
566 gst_query_set_latency (GstQuery * query, gboolean live,
567 GstClockTime min_latency, GstClockTime max_latency)
569 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_LATENCY);
571 gst_structure_id_set (query->structure,
572 GST_QUARK (LIVE), G_TYPE_BOOLEAN, live,
573 GST_QUARK (MIN_LATENCY), G_TYPE_UINT64, min_latency,
574 GST_QUARK (MAX_LATENCY), G_TYPE_UINT64, max_latency, NULL);
578 * gst_query_parse_latency:
579 * @query: a #GstQuery
580 * @live: (out) (allow-none): storage for live or NULL
581 * @min_latency: (out) (allow-none): the storage for the min latency or NULL
582 * @max_latency: (out) (allow-none): the storage for the max latency or NULL
584 * Parse a latency query answer.
589 gst_query_parse_latency (GstQuery * query, gboolean * live,
590 GstClockTime * min_latency, GstClockTime * max_latency)
592 GstStructure *structure;
594 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_LATENCY);
596 structure = query->structure;
599 g_value_get_boolean (gst_structure_id_get_value (structure,
602 *min_latency = g_value_get_uint64 (gst_structure_id_get_value (structure,
603 GST_QUARK (MIN_LATENCY)));
605 *max_latency = g_value_get_uint64 (gst_structure_id_get_value (structure,
606 GST_QUARK (MAX_LATENCY)));
610 * gst_query_new_convert:
611 * @src_format: the source #GstFormat for the new query
612 * @value: the value to convert
613 * @dest_format: the target #GstFormat
615 * Constructs a new convert query object. Use gst_query_unref()
616 * when done with it. A convert query is used to ask for a conversion between
617 * one format and another.
619 * Free-function: gst_query_unref
621 * Returns: (transfer full): a #GstQuery
624 gst_query_new_convert (GstFormat src_format, gint64 value,
625 GstFormat dest_format)
628 GstStructure *structure;
630 structure = gst_structure_id_new (GST_QUARK (QUERY_CONVERT),
631 GST_QUARK (SRC_FORMAT), GST_TYPE_FORMAT, src_format,
632 GST_QUARK (SRC_VALUE), G_TYPE_INT64, value,
633 GST_QUARK (DEST_FORMAT), GST_TYPE_FORMAT, dest_format,
634 GST_QUARK (DEST_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
636 query = gst_query_new (GST_QUERY_CONVERT, structure);
642 * gst_query_set_convert:
643 * @query: a #GstQuery
644 * @src_format: the source #GstFormat
645 * @src_value: the source value
646 * @dest_format: the destination #GstFormat
647 * @dest_value: the destination value
649 * Answer a convert query by setting the requested values.
652 gst_query_set_convert (GstQuery * query, GstFormat src_format, gint64 src_value,
653 GstFormat dest_format, gint64 dest_value)
655 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONVERT);
657 gst_structure_id_set (query->structure,
658 GST_QUARK (SRC_FORMAT), GST_TYPE_FORMAT, src_format,
659 GST_QUARK (SRC_VALUE), G_TYPE_INT64, src_value,
660 GST_QUARK (DEST_FORMAT), GST_TYPE_FORMAT, dest_format,
661 GST_QUARK (DEST_VALUE), G_TYPE_INT64, dest_value, NULL);
665 * gst_query_parse_convert:
666 * @query: a #GstQuery
667 * @src_format: (out) (allow-none): the storage for the #GstFormat of the
668 * source value, or NULL
669 * @src_value: (out) (allow-none): the storage for the source value, or NULL
670 * @dest_format: (out) (allow-none): the storage for the #GstFormat of the
671 * destination value, or NULL
672 * @dest_value: (out) (allow-none): the storage for the destination value,
675 * Parse a convert query answer. Any of @src_format, @src_value, @dest_format,
676 * and @dest_value may be NULL, in which case that value is omitted.
679 gst_query_parse_convert (GstQuery * query, GstFormat * src_format,
680 gint64 * src_value, GstFormat * dest_format, gint64 * dest_value)
682 GstStructure *structure;
684 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONVERT);
686 structure = query->structure;
689 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
690 GST_QUARK (SRC_FORMAT)));
692 *src_value = g_value_get_int64 (gst_structure_id_get_value (structure,
693 GST_QUARK (SRC_VALUE)));
696 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
697 GST_QUARK (DEST_FORMAT)));
699 *dest_value = g_value_get_int64 (gst_structure_id_get_value (structure,
700 GST_QUARK (DEST_VALUE)));
704 * gst_query_new_segment:
705 * @format: the #GstFormat for the new query
707 * Constructs a new segment query object. Use gst_query_unref()
708 * when done with it. A segment query is used to discover information about the
709 * currently configured segment for playback.
711 * Free-function: gst_query_unref
713 * Returns: (transfer full): a new #GstQuery
716 gst_query_new_segment (GstFormat format)
719 GstStructure *structure;
721 structure = gst_structure_id_new (GST_QUARK (QUERY_SEGMENT),
722 GST_QUARK (RATE), G_TYPE_DOUBLE, (gdouble) 0.0,
723 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
724 GST_QUARK (START_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
725 GST_QUARK (STOP_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
727 query = gst_query_new (GST_QUERY_SEGMENT, structure);
733 * gst_query_set_segment:
734 * @query: a #GstQuery
735 * @rate: the rate of the segment
736 * @format: the #GstFormat of the segment values (@start_value and @stop_value)
737 * @start_value: the start value
738 * @stop_value: the stop value
740 * Answer a segment query by setting the requested values. The normal
741 * playback segment of a pipeline is 0 to duration at the default rate of
742 * 1.0. If a seek was performed on the pipeline to play a different
743 * segment, this query will return the range specified in the last seek.
745 * @start_value and @stop_value will respectively contain the configured
746 * playback range start and stop values expressed in @format.
747 * The values are always between 0 and the duration of the media and
748 * @start_value <= @stop_value. @rate will contain the playback rate. For
749 * negative rates, playback will actually happen from @stop_value to
753 gst_query_set_segment (GstQuery * query, gdouble rate, GstFormat format,
754 gint64 start_value, gint64 stop_value)
756 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEGMENT);
758 gst_structure_id_set (query->structure,
759 GST_QUARK (RATE), G_TYPE_DOUBLE, rate,
760 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
761 GST_QUARK (START_VALUE), G_TYPE_INT64, start_value,
762 GST_QUARK (STOP_VALUE), G_TYPE_INT64, stop_value, NULL);
766 * gst_query_parse_segment:
767 * @query: a #GstQuery
768 * @rate: (out) (allow-none): the storage for the rate of the segment, or NULL
769 * @format: (out) (allow-none): the storage for the #GstFormat of the values,
771 * @start_value: (out) (allow-none): the storage for the start value, or NULL
772 * @stop_value: (out) (allow-none): the storage for the stop value, or NULL
774 * Parse a segment query answer. Any of @rate, @format, @start_value, and
775 * @stop_value may be NULL, which will cause this value to be omitted.
777 * See gst_query_set_segment() for an explanation of the function arguments.
780 gst_query_parse_segment (GstQuery * query, gdouble * rate, GstFormat * format,
781 gint64 * start_value, gint64 * stop_value)
783 GstStructure *structure;
785 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEGMENT);
787 structure = query->structure;
789 *rate = g_value_get_double (gst_structure_id_get_value (structure,
793 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
794 GST_QUARK (FORMAT)));
796 *start_value = g_value_get_int64 (gst_structure_id_get_value (structure,
797 GST_QUARK (START_VALUE)));
799 *stop_value = g_value_get_int64 (gst_structure_id_get_value (structure,
800 GST_QUARK (STOP_VALUE)));
804 * gst_query_new_application:
805 * @type: the query type
806 * @structure: a structure for the query
808 * Constructs a new custom application query object. Use gst_query_unref()
811 * Free-function: gst_query_unref
813 * Returns: (transfer full): a new #GstQuery
816 gst_query_new_application (GstQueryType type, GstStructure * structure)
818 g_return_val_if_fail (gst_query_type_get_details (type) != NULL, NULL);
819 g_return_val_if_fail (structure != NULL, NULL);
821 return gst_query_new (type, structure);
825 * gst_query_get_structure:
826 * @query: a #GstQuery
828 * Get the structure of a query.
830 * Returns: (transfer none): the #GstStructure of the query. The structure is
831 * still owned by the query and will therefore be freed when the query
835 gst_query_get_structure (GstQuery * query)
837 g_return_val_if_fail (GST_IS_QUERY (query), NULL);
839 return query->structure;
843 * gst_query_new_seeking:
844 * @format: the default #GstFormat for the new query
846 * Constructs a new query object for querying seeking properties of
849 * Free-function: gst_query_unref
851 * Returns: (transfer full): a new #GstQuery
854 gst_query_new_seeking (GstFormat format)
857 GstStructure *structure;
859 structure = gst_structure_id_new (GST_QUARK (QUERY_SEEKING),
860 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
861 GST_QUARK (SEEKABLE), G_TYPE_BOOLEAN, FALSE,
862 GST_QUARK (SEGMENT_START), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
863 GST_QUARK (SEGMENT_END), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
865 query = gst_query_new (GST_QUERY_SEEKING, structure);
871 * gst_query_set_seeking:
872 * @query: a #GstQuery
873 * @format: the format to set for the @segment_start and @segment_end values
874 * @seekable: the seekable flag to set
875 * @segment_start: the segment_start to set
876 * @segment_end: the segment_end to set
878 * Set the seeking query result fields in @query.
881 gst_query_set_seeking (GstQuery * query, GstFormat format,
882 gboolean seekable, gint64 segment_start, gint64 segment_end)
884 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEEKING);
886 gst_structure_id_set (query->structure,
887 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
888 GST_QUARK (SEEKABLE), G_TYPE_BOOLEAN, seekable,
889 GST_QUARK (SEGMENT_START), G_TYPE_INT64, segment_start,
890 GST_QUARK (SEGMENT_END), G_TYPE_INT64, segment_end, NULL);
894 * gst_query_parse_seeking:
895 * @query: a GST_QUERY_SEEKING type query #GstQuery
896 * @format: (out) (allow-none): the format to set for the @segment_start
897 * and @segment_end values, or NULL
898 * @seekable: (out) (allow-none): the seekable flag to set, or NULL
899 * @segment_start: (out) (allow-none): the segment_start to set, or NULL
900 * @segment_end: (out) (allow-none): the segment_end to set, or NULL
902 * Parse a seeking query, writing the format into @format, and
903 * other results into the passed parameters, if the respective parameters
907 gst_query_parse_seeking (GstQuery * query, GstFormat * format,
908 gboolean * seekable, gint64 * segment_start, gint64 * segment_end)
910 GstStructure *structure;
912 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SEEKING);
914 structure = query->structure;
917 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
918 GST_QUARK (FORMAT)));
920 *seekable = g_value_get_boolean (gst_structure_id_get_value (structure,
921 GST_QUARK (SEEKABLE)));
923 *segment_start = g_value_get_int64 (gst_structure_id_get_value (structure,
924 GST_QUARK (SEGMENT_START)));
926 *segment_end = g_value_get_int64 (gst_structure_id_get_value (structure,
927 GST_QUARK (SEGMENT_END)));
931 * gst_query_new_formats:
933 * Constructs a new query object for querying formats of
936 * Free-function: gst_query_unref
938 * Returns: (transfer full): a new #GstQuery
943 gst_query_new_formats (void)
946 GstStructure *structure;
948 structure = gst_structure_id_empty_new (GST_QUARK (QUERY_FORMATS));
949 query = gst_query_new (GST_QUERY_FORMATS, structure);
955 gst_query_list_add_format (GValue * list, GstFormat format)
957 GValue item = { 0, };
959 g_value_init (&item, GST_TYPE_FORMAT);
960 g_value_set_enum (&item, format);
961 gst_value_list_append_value (list, &item);
962 g_value_unset (&item);
966 * gst_query_set_formats:
967 * @query: a #GstQuery
968 * @n_formats: the number of formats to set.
969 * @...: A number of @GstFormats equal to @n_formats.
971 * Set the formats query result fields in @query. The number of formats passed
972 * must be equal to @n_formats.
975 gst_query_set_formats (GstQuery * query, gint n_formats, ...)
978 GValue list = { 0, };
981 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
983 g_value_init (&list, GST_TYPE_LIST);
985 va_start (ap, n_formats);
986 for (i = 0; i < n_formats; i++) {
987 gst_query_list_add_format (&list, va_arg (ap, GstFormat));
991 gst_structure_set_value (query->structure, "formats", &list);
993 g_value_unset (&list);
998 * gst_query_set_formatsv:
999 * @query: a #GstQuery
1000 * @n_formats: the number of formats to set.
1001 * @formats: (in) (array length=n_formats): an array containing @n_formats
1002 * @GstFormat values.
1004 * Set the formats query result fields in @query. The number of formats passed
1005 * in the @formats array must be equal to @n_formats.
1010 gst_query_set_formatsv (GstQuery * query, gint n_formats,
1011 const GstFormat * formats)
1013 GValue list = { 0, };
1016 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
1018 g_value_init (&list, GST_TYPE_LIST);
1019 for (i = 0; i < n_formats; i++) {
1020 gst_query_list_add_format (&list, formats[i]);
1022 gst_structure_set_value (query->structure, "formats", &list);
1024 g_value_unset (&list);
1028 * gst_query_parse_formats_length:
1029 * @query: a #GstQuery
1030 * @n_formats: (out): the number of formats in this query.
1032 * Parse the number of formats in the formats @query.
1037 gst_query_parse_formats_length (GstQuery * query, guint * n_formats)
1039 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
1044 list = gst_structure_get_value (query->structure, "formats");
1048 *n_formats = gst_value_list_get_size (list);
1053 * gst_query_parse_formats_nth:
1054 * @query: a #GstQuery
1055 * @nth: (out): the nth format to retrieve.
1056 * @format: (out): a pointer to store the nth format
1058 * Parse the format query and retrieve the @nth format from it into
1059 * @format. If the list contains less elements than @nth, @format will be
1060 * set to GST_FORMAT_UNDEFINED.
1065 gst_query_parse_formats_nth (GstQuery * query, guint nth, GstFormat * format)
1067 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_FORMATS);
1072 list = gst_structure_get_value (query->structure, "formats");
1074 *format = GST_FORMAT_UNDEFINED;
1076 if (nth < gst_value_list_get_size (list)) {
1078 (GstFormat) g_value_get_enum (gst_value_list_get_value (list, nth));
1080 *format = GST_FORMAT_UNDEFINED;
1086 * gst_query_new_buffering
1087 * @format: the default #GstFormat for the new query
1089 * Constructs a new query object for querying the buffering status of
1092 * Free-function: gst_query_new
1094 * Returns: (transfer full): a new #GstQuery
1099 gst_query_new_buffering (GstFormat format)
1102 GstStructure *structure;
1104 /* by default, we configure the answer as no buffering with a 100% buffering
1106 structure = gst_structure_id_new (GST_QUARK (QUERY_BUFFERING),
1107 GST_QUARK (BUSY), G_TYPE_BOOLEAN, FALSE,
1108 GST_QUARK (BUFFER_PERCENT), G_TYPE_INT, 100,
1109 GST_QUARK (BUFFERING_MODE), GST_TYPE_BUFFERING_MODE, GST_BUFFERING_STREAM,
1110 GST_QUARK (AVG_IN_RATE), G_TYPE_INT, -1,
1111 GST_QUARK (AVG_OUT_RATE), G_TYPE_INT, -1,
1112 GST_QUARK (BUFFERING_LEFT), G_TYPE_INT64, G_GINT64_CONSTANT (0),
1113 GST_QUARK (ESTIMATED_TOTAL), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
1114 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
1115 GST_QUARK (START_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
1116 GST_QUARK (STOP_VALUE), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
1118 query = gst_query_new (GST_QUERY_BUFFERING, structure);
1124 * gst_query_set_buffering_percent
1125 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1126 * @busy: if buffering is busy
1127 * @percent: a buffering percent
1129 * Set the percentage of buffered data. This is a value between 0 and 100.
1130 * The @busy indicator is %TRUE when the buffering is in progress.
1135 gst_query_set_buffering_percent (GstQuery * query, gboolean busy, gint percent)
1137 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1138 g_return_if_fail (percent >= 0 && percent <= 100);
1140 gst_structure_id_set (query->structure,
1141 GST_QUARK (BUSY), G_TYPE_BOOLEAN, busy,
1142 GST_QUARK (BUFFER_PERCENT), G_TYPE_INT, percent, NULL);
1146 * gst_query_parse_buffering_percent
1147 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1148 * @busy: (out) (allow-none): if buffering is busy, or NULL
1149 * @percent: (out) (allow-none): a buffering percent, or NULL
1151 * Get the percentage of buffered data. This is a value between 0 and 100.
1152 * The @busy indicator is %TRUE when the buffering is in progress.
1157 gst_query_parse_buffering_percent (GstQuery * query, gboolean * busy,
1160 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1163 *busy = g_value_get_boolean (gst_structure_id_get_value (query->structure,
1166 *percent = g_value_get_int (gst_structure_id_get_value (query->structure,
1167 GST_QUARK (BUFFER_PERCENT)));
1171 * gst_query_set_buffering_stats:
1172 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1173 * @mode: a buffering mode
1174 * @avg_in: the average input rate
1175 * @avg_out: the average output rate
1176 * @buffering_left: amount of buffering time left
1178 * Configures the buffering stats values in @query.
1183 gst_query_set_buffering_stats (GstQuery * query, GstBufferingMode mode,
1184 gint avg_in, gint avg_out, gint64 buffering_left)
1186 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1188 gst_structure_id_set (query->structure,
1189 GST_QUARK (BUFFERING_MODE), GST_TYPE_BUFFERING_MODE, mode,
1190 GST_QUARK (AVG_IN_RATE), G_TYPE_INT, avg_in,
1191 GST_QUARK (AVG_OUT_RATE), G_TYPE_INT, avg_out,
1192 GST_QUARK (BUFFERING_LEFT), G_TYPE_INT64, buffering_left, NULL);
1196 * gst_query_parse_buffering_stats:
1197 * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
1198 * @mode: (out) (allow-none): a buffering mode, or NULL
1199 * @avg_in: (out) (allow-none): the average input rate, or NULL
1200 * @avg_out: (out) (allow-none): the average output rat, or NULLe
1201 * @buffering_left: (out) (allow-none): amount of buffering time left, or NULL
1203 * Extracts the buffering stats values from @query.
1208 gst_query_parse_buffering_stats (GstQuery * query,
1209 GstBufferingMode * mode, gint * avg_in, gint * avg_out,
1210 gint64 * buffering_left)
1212 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1215 *mode = (GstBufferingMode)
1216 g_value_get_enum (gst_structure_id_get_value (query->structure,
1217 GST_QUARK (BUFFERING_MODE)));
1219 *avg_in = g_value_get_int (gst_structure_id_get_value (query->structure,
1220 GST_QUARK (AVG_IN_RATE)));
1222 *avg_out = g_value_get_int (gst_structure_id_get_value (query->structure,
1223 GST_QUARK (AVG_OUT_RATE)));
1226 g_value_get_int64 (gst_structure_id_get_value (query->structure,
1227 GST_QUARK (BUFFERING_LEFT)));
1232 * gst_query_set_buffering_range:
1233 * @query: a #GstQuery
1234 * @format: the format to set for the @start and @stop values
1235 * @start: the start to set
1236 * @stop: the stop to set
1237 * @estimated_total: estimated total amount of download time
1239 * Set the available query result fields in @query.
1244 gst_query_set_buffering_range (GstQuery * query, GstFormat format,
1245 gint64 start, gint64 stop, gint64 estimated_total)
1247 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1249 gst_structure_id_set (query->structure,
1250 GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
1251 GST_QUARK (START_VALUE), G_TYPE_INT64, start,
1252 GST_QUARK (STOP_VALUE), G_TYPE_INT64, stop,
1253 GST_QUARK (ESTIMATED_TOTAL), G_TYPE_INT64, estimated_total, NULL);
1257 * gst_query_parse_buffering_range:
1258 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1259 * @format: (out) (allow-none): the format to set for the @segment_start
1260 * and @segment_end values, or NULL
1261 * @start: (out) (allow-none): the start to set, or NULL
1262 * @stop: (out) (allow-none): the stop to set, or NULL
1263 * @estimated_total: (out) (allow-none): estimated total amount of download
1266 * Parse an available query, writing the format into @format, and
1267 * other results into the passed parameters, if the respective parameters
1273 gst_query_parse_buffering_range (GstQuery * query, GstFormat * format,
1274 gint64 * start, gint64 * stop, gint64 * estimated_total)
1276 GstStructure *structure;
1278 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING);
1280 structure = query->structure;
1283 (GstFormat) g_value_get_enum (gst_structure_id_get_value (structure,
1284 GST_QUARK (FORMAT)));
1286 *start = g_value_get_int64 (gst_structure_id_get_value (structure,
1287 GST_QUARK (START_VALUE)));
1289 *stop = g_value_get_int64 (gst_structure_id_get_value (structure,
1290 GST_QUARK (STOP_VALUE)));
1291 if (estimated_total)
1293 g_value_get_int64 (gst_structure_id_get_value (structure,
1294 GST_QUARK (ESTIMATED_TOTAL)));
1298 * gst_query_add_buffering_range
1299 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1300 * @start: start position of the range
1301 * @stop: stop position of the range
1303 * Set the buffering-ranges array field in @query. The current last
1304 * start position of the array should be inferior to @start.
1306 * Returns: a #gboolean indicating if the range was added or not.
1311 gst_query_add_buffering_range (GstQuery * query, gint64 start, gint64 stop)
1314 GValue *last_array_value;
1315 const GValue *value;
1316 GValue range_value = { 0 };
1318 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING, FALSE);
1320 if (G_UNLIKELY (start >= stop))
1324 gst_structure_id_get_value (query->structure,
1325 GST_QUARK (BUFFERING_RANGES));
1327 array = (GValueArray *) g_value_get_boxed (value);
1328 last_array_value = g_value_array_get_nth (array, array->n_values - 1);
1329 if (G_UNLIKELY (start <= gst_value_get_int64_range_min (last_array_value)))
1332 GValue new_array_val = { 0, };
1334 array = g_value_array_new (0);
1336 g_value_init (&new_array_val, G_TYPE_VALUE_ARRAY);
1337 g_value_take_boxed (&new_array_val, array);
1339 /* set the value array only once, so we then modify (append to) the
1340 * existing value array owned by the GstStructure / the field's GValue */
1341 gst_structure_id_take_value (query->structure, GST_QUARK (BUFFERING_RANGES),
1345 g_value_init (&range_value, GST_TYPE_INT64_RANGE);
1346 gst_value_set_int64_range (&range_value, start, stop);
1347 g_value_array_append (array, &range_value);
1348 /* skip the g_value_unset(&range_value) here, we know it's not needed */
1354 * gst_query_get_n_buffering_ranges
1355 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1357 * Retrieve the number of values currently stored in the
1358 * buffered-ranges array of the query's structure.
1360 * Returns: the range array size as a #guint.
1365 gst_query_get_n_buffering_ranges (GstQuery * query)
1368 const GValue *value;
1371 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING, 0);
1374 gst_structure_id_get_value (query->structure,
1375 GST_QUARK (BUFFERING_RANGES));
1377 array = (GValueArray *) g_value_get_boxed (value);
1378 size = array->n_values;
1385 * gst_query_parse_nth_buffering_range
1386 * @query: a GST_QUERY_BUFFERING type query #GstQuery
1387 * @index: position in the buffered-ranges array to read
1388 * @start: (out) (allow-none): the start position to set, or NULL
1389 * @stop: (out) (allow-none): the stop position to set, or NULL
1391 * Parse an available query and get the start and stop values stored
1392 * at the @index of the buffered ranges array.
1394 * Returns: a #gboolean indicating if the parsing succeeded.
1399 gst_query_parse_nth_buffering_range (GstQuery * query, guint index,
1400 gint64 * start, gint64 * stop)
1402 const GValue *value;
1403 GValueArray *ranges;
1404 GValue *range_value;
1405 gboolean ret = FALSE;
1407 g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BUFFERING, ret);
1410 gst_structure_id_get_value (query->structure,
1411 GST_QUARK (BUFFERING_RANGES));
1412 ranges = (GValueArray *) g_value_get_boxed (value);
1413 range_value = g_value_array_get_nth (ranges, index);
1416 *start = gst_value_get_int64_range_min (range_value);
1418 *stop = gst_value_get_int64_range_max (range_value);
1427 * gst_query_new_uri:
1429 * Constructs a new query URI query object. Use gst_query_unref()
1430 * when done with it. An URI query is used to query the current URI
1431 * that is used by the source or sink.
1433 * Free-function: gst_query_unref
1435 * Returns: (transfer full): a new #GstQuery
1440 gst_query_new_uri (void)
1443 GstStructure *structure;
1445 structure = gst_structure_id_new (GST_QUARK (QUERY_URI),
1446 GST_QUARK (URI), G_TYPE_STRING, NULL, NULL);
1448 query = gst_query_new (GST_QUERY_URI, structure);
1454 * gst_query_set_uri:
1455 * @query: a #GstQuery with query type GST_QUERY_URI
1456 * @uri: the URI to set
1458 * Answer a URI query by setting the requested URI.
1463 gst_query_set_uri (GstQuery * query, const gchar * uri)
1465 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
1466 g_return_if_fail (gst_uri_is_valid (uri));
1468 gst_structure_id_set (query->structure, GST_QUARK (URI), G_TYPE_STRING, uri,
1473 * gst_query_parse_uri:
1474 * @query: a #GstQuery
1475 * @uri: (out callee-allocates) (allow-none): the storage for the current URI
1478 * Parse an URI query, writing the URI into @uri as a newly
1479 * allocated string, if the respective parameters are non-NULL.
1480 * Free the string with g_free() after usage.
1485 gst_query_parse_uri (GstQuery * query, gchar ** uri)
1487 g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
1490 *uri = g_value_dup_string (gst_structure_id_get_value (query->structure,