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  *
   5  * gstpad.h: Header for GstPad object
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Library General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Library General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Library General Public
  18  * License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  */
  22
  23
  24 #ifndef __GST_QUERY_H__
  25 #define __GST_QUERY_H__
  26
  27 #include <glib.h>
  28
  29 G_BEGIN_DECLS
  30
  31 typedef enum {
  32   GST_QUERY_NONE = 0,
  33   GST_QUERY_TOTAL,
  34   GST_QUERY_POSITION,
  35   GST_QUERY_LATENCY,
  36   GST_QUERY_JITTER,
  37   GST_QUERY_START,
  38   GST_QUERY_SEGMENT_END,
  39   GST_QUERY_RATE
  40 } GstQueryType;
  41
  42 /* rate is relative to 1000000LL  */
  43 #define GST_QUERY_TYPE_RATE_DEN          1000000LL
  44
  45 typedef struct _GstQueryTypeDefinition GstQueryTypeDefinition;
  46
  47 struct _GstQueryTypeDefinition
  48 {
  49   GstQueryType   value;
  50   gchar         *nick;
  51   gchar         *description;
  52 };
  53
  54 #ifdef G_HAVE_ISO_VARARGS
  55 #define GST_QUERY_TYPE_FUNCTION(type, functionname, ...)        \
  56 static const GstQueryType*                              \
  57 functionname (type object)                              \
  58 {                                                       \
  59   static const GstQueryType types[] = {                 \
  60     __VA_ARGS__,                                        \
  61     0                                                   \
  62   };                                                    \
  63   return types;                                         \
  64 }
  65 #elif defined(G_HAVE_GNUC_VARARGS)
  66 #define GST_QUERY_TYPE_FUNCTION(type, functionname, a...)       \
  67 static const GstQueryType*                              \
  68 functionname (type object)                              \
  69 {                                                       \
  70   static const GstQueryType types[] = {                 \
  71     a,                                                  \
  72     0                                                   \
  73   };                                                    \
  74   return types;                                         \
  75 }
  76 #endif
  77
  78 void                    _gst_query_type_initialize     (void);
  79
  80 /* register a new query */
  81 GstQueryType            gst_query_type_register        (const gchar *nick,
  82                                                         const gchar *description);
  83 GstQueryType            gst_query_type_get_by_nick     (const gchar *nick);
  84
  85 /* check if a query is in an array of querys */
  86 gboolean                gst_query_types_contains       (const GstQueryType *types, GstQueryType type);
  87
  88 /* query for query details */
  89 const GstQueryTypeDefinition*
  90                         gst_query_type_get_details     (GstQueryType type);
  91 const GList*            gst_query_type_get_definitions (void);
  92
  93 G_END_DECLS
  94
  95 #endif /* __GST_QUERY_H__ */
  96