1 /* GStreamer
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>
5 *
6 * gstquery.h: GstQuery API declaration
7 *
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.
12 *
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.
17 *
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.
22 */
25 #ifndef __GST_QUERY_H__
26 #define __GST_QUERY_H__
28 #include <glib.h>
30 #include <gst/gstiterator.h>
31 #include <gst/gstdata.h>
32 #include <gst/gststructure.h>
33 #include <gst/gstformat.h>
35 G_BEGIN_DECLS
37 typedef enum {
38 GST_QUERY_NONE = 0,
39 GST_QUERY_TOTAL, /* deprecated, use POSITION */
40 GST_QUERY_POSITION,
41 GST_QUERY_LATENCY,
42 GST_QUERY_JITTER, /* not in draft-query, necessary? */
43 GST_QUERY_START, /* deprecated, use SEEKING */
44 GST_QUERY_SEGMENT_END, /* deprecated, use SEEKING */
45 GST_QUERY_RATE, /* not in draft-query, necessary? */
46 GST_QUERY_SEEKING,
47 GST_QUERY_CONVERT,
48 GST_QUERY_FORMATS
49 } GstQueryType;
51 /* rate is relative to 1000000 */
52 #define GST_QUERY_TYPE_RATE_DEN G_GINT64_CONSTANT (1000000)
54 typedef struct _GstQueryTypeDefinition GstQueryTypeDefinition;
55 typedef struct _GstQuery GstQuery;
57 struct _GstQueryTypeDefinition
58 {
59 GstQueryType value;
60 gchar *nick;
61 gchar *description;
62 };
64 #ifdef G_HAVE_ISO_VARARGS
65 #define GST_QUERY_TYPE_FUNCTION(type, functionname, ...) \
66 static const GstQueryType* \
67 functionname (type object) \
68 { \
69 static const GstQueryType types[] = { \
70 __VA_ARGS__, \
71 0 \
72 }; \
73 return types; \
74 }
75 #elif defined(G_HAVE_GNUC_VARARGS)
76 #define GST_QUERY_TYPE_FUNCTION(type, functionname, a...) \
77 static const GstQueryType* \
78 functionname (type object) \
79 { \
80 static const GstQueryType types[] = { \
81 a, \
82 0 \
83 }; \
84 return types; \
85 }
86 #endif
88 GST_EXPORT GType _gst_query_type;
90 #define GST_TYPE_QUERY (_gst_query_type)
91 #define GST_QUERY(query) ((GstQuery*)(query))
92 #define GST_IS_QUERY(query) (GST_DATA_TYPE(query) == GST_TYPE_QUERY)
93 #define GST_QUERY_TYPE(query) (((GstQuery*)(query))->type)
95 struct _GstQuery
96 {
97 GstData data;
99 /*< public > */
100 GstQueryType type;
102 GstStructure *structure;
104 /*< private > */
105 gpointer _gst_reserved[GST_PADDING];
106 };
108 void _gst_query_initialize (void);
109 GType gst_query_get_type (void);
111 /* register a new query */
112 GstQueryType gst_query_type_register (const gchar *nick,
113 const gchar *description);
114 GstQueryType gst_query_type_get_by_nick (const gchar *nick);
116 /* check if a query is in an array of querys */
117 gboolean gst_query_types_contains (const GstQueryType *types,
118 GstQueryType type);
120 /* query for query details */
121 G_CONST_RETURN GstQueryTypeDefinition*
122 gst_query_type_get_details (GstQueryType type);
123 GstIterator* gst_query_type_iterate_definitions (void);
125 /* refcounting */
126 #define gst_query_ref(msg) GST_QUERY (gst_data_ref (GST_DATA (msg)))
127 #define gst_query_ref_by_count(msg,c) GST_QUERY (gst_data_ref_by_count (GST_DATA (msg), (c)))
128 #define gst_query_unref(msg) gst_data_unref (GST_DATA (msg))
129 /* copy query */
130 #define gst_query_copy(msg) GST_QUERY (gst_data_copy (GST_DATA (msg)))
131 #define gst_query_copy_on_write(msg) GST_QUERY (gst_data_copy_on_write (GST_DATA (msg)))
133 /* position query */
134 GstQuery* gst_query_new_position (GstFormat format);
135 void gst_query_set_position (GstQuery *query, GstFormat format,
136 gint64 cur, gint64 end);
137 void gst_query_parse_position (GstQuery *query, GstFormat *format,
138 gint64 *cur, gint64 *end);
139 /* convert query */
140 GstQuery* gst_query_new_convert (GstFormat src_fmt, gint64 value, GstFormat dest_fmt);
141 void gst_query_set_convert (GstQuery *query, GstFormat src_format, gint64 src_value,
142 GstFormat dest_format, gint64 dest_value);
143 void gst_query_parse_convert (GstQuery *query, GstFormat *src_format, gint64 *src_value,
144 GstFormat *dest_format, gint64 *dest_value);
146 /* application specific query */
147 GstQuery * gst_query_new_application (GstQueryType type,
148 GstStructure *structure);
151 GstStructure * gst_query_get_structure (GstQuery *query);
153 /* hmm */
154 #define GST_QUERY_POSITION_GET_FORMAT(q) \
155 (gst_structure_get_int ((q)->structure, "format"))
157 G_END_DECLS
159 #endif /* __GST_QUERY_H__ */