gst/gstquery.h

   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  */
  23
  24
  25 #ifndef __GST_QUERY_H__
  26 #define __GST_QUERY_H__
  27
  28 #include <glib.h>
  29
  30 #include <gst/gstiterator.h>
  31
  32 G_BEGIN_DECLS
  33
  34 typedef enum {
  35   GST_QUERY_NONE = 0,
  36   GST_QUERY_TOTAL,
  37   GST_QUERY_POSITION,
  38   GST_QUERY_LATENCY,
  39   GST_QUERY_JITTER,
  40   GST_QUERY_START,
  41   GST_QUERY_SEGMENT_END,
  42   GST_QUERY_RATE
  43 } GstQueryType;
  44
  45 /* rate is relative to 1000000  */
  46 #define GST_QUERY_TYPE_RATE_DEN          G_GINT64_CONSTANT (1000000)
  47
  48 typedef struct _GstQueryTypeDefinition GstQueryTypeDefinition;
  49
  50 struct _GstQueryTypeDefinition
  51 {
  52   GstQueryType   value;
  53   gchar         *nick;
  54   gchar         *description;
  55 };
  56
  57 #ifdef G_HAVE_ISO_VARARGS
  58 #define GST_QUERY_TYPE_FUNCTION(type, functionname, ...)        \
  59 static const GstQueryType*                              \
  60 functionname (type object)                              \
  61 {                                                       \
  62   static const GstQueryType types[] = {                 \
  63     __VA_ARGS__,                                        \
  64     0                                                   \
  65   };                                                    \
  66   return types;                                         \
  67 }
  68 #elif defined(G_HAVE_GNUC_VARARGS)
  69 #define GST_QUERY_TYPE_FUNCTION(type, functionname, a...)       \
  70 static const GstQueryType*                              \
  71 functionname (type object)                              \
  72 {                                                       \
  73   static const GstQueryType types[] = {                 \
  74     a,                                                  \
  75     0                                                   \
  76   };                                                    \
  77   return types;                                         \
  78 }
  79 #endif
  80
  81 void                    _gst_query_type_initialize     (void);
  82
  83 /* register a new query */
  84 GstQueryType            gst_query_type_register        (const gchar *nick,
  85                                                         const gchar *description);
  86 GstQueryType            gst_query_type_get_by_nick     (const gchar *nick);
  87
  88 /* check if a query is in an array of querys */
  89 gboolean                gst_query_types_contains       (const GstQueryType *types, GstQueryType type);
  90
  91 /* query for query details */
  92 G_CONST_RETURN GstQueryTypeDefinition*
  93                         gst_query_type_get_details         (GstQueryType type);
  94 GstIterator*            gst_query_type_iterate_definitions (void);
  95
  96 G_END_DECLS
  97
  98 #endif /* __GST_QUERY_H__ */
  99