Make the formats dynamic so that plugins can register new seek/query formats

Original commit message from CVS:
Make the formats dynamic so that plugins can register new seek/query
formats
This commit is contained in:
Wim Taymans 2002-07-28 01:54:42 +00:00
parent a444a6ccc5
commit c8d3e2e9a9
4 changed files with 182 additions and 8 deletions

View file

@ -64,6 +64,7 @@ libgstreamer_la_SOURCES = \
gstelementfactory.c \
gstevent.c \
gstextratypes.c \
gstformat.c \
gstinfo.c \
gstmemchunk.c \
gstpad.c \

View file

@ -351,6 +351,7 @@ init_post (void)
GST_INFO (GST_CAT_GST_INIT, "Initializing GStreamer Core Library version %s %s",
GST_VERSION, _gst_use_threads?"":"(no threads)");
_gst_format_initialize ();
gst_object_get_type ();
gst_pad_get_type ();
gst_real_pad_get_type ();

161
gst/gstformat.c Normal file
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@ -0,0 +1,161 @@
/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wim.taymans@chello.be>
*
* gstformat.c: GstFormat registration
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "gstlog.h"
#include "gstformat.h"
static GList *_gst_formats = NULL;
static gint _n_values = 1; /* we start from 1 because 0 reserved for UNDEFINED */
typedef struct _GstFormatDefinition GstFormatDefinition;
struct _GstFormatDefinition
{
GstFormat value;
gchar *nick;
gchar *description;
};
static GstFormatDefinition standard_definitions[] = {
{ GST_FORMAT_DEFAULT, "default", "Default" },
{ GST_FORMAT_BYTES, "bytes", "Bytes" },
{ GST_FORMAT_TIME, "time", "Time" },
{ GST_FORMAT_BUFFERS, "buffers", "Buffers" },
{ GST_FORMAT_PERCENT, "percent", "Percent" },
{ GST_FORMAT_UNITS, "units", "Units as defined by the media type" },
{ 0, NULL, NULL }
};
void
_gst_format_initialize (void)
{
GstFormatDefinition *standards = standard_definitions;
while (standards->nick) {
_gst_formats = g_list_prepend (_gst_formats, standards);
standards++;
}
}
/**
* gst_format_register:
* @nick: The nick of the new format
* @description: The description of the new format
*
* Create a new GstFormat based on the nick or return an
* allrady registered format with that nick
*
* Returns: A new GstFormat or an already registered format
* with the same nick.
*/
GstFormat
gst_format_register (const gchar *nick, const gchar *description)
{
GstFormatDefinition *format;
GstFormat query;
g_return_val_if_fail (nick != NULL, 0);
g_return_val_if_fail (description != NULL, 0);
query = gst_format_get_by_nick (nick);
if (query != GST_FORMAT_UNDEFINED)
return query;
format = g_new0 (GstFormatDefinition, 1);
format->value = _n_values;
format->nick = g_strdup (nick);
format->description = g_strdup (description);
_gst_formats = g_list_prepend (_gst_formats, format);
_n_values++;
return format->value;
}
/**
* gst_format_get_by_nick:
* @nick: The nick of the format
*
* Return the format registered with the given nick.
*
* Returns: The format with @nick or GST_FORMAT_UNDEFINED
* if the format was not registered.
*/
GstFormat
gst_format_get_by_nick (const gchar *nick)
{
GList *walk;
GstFormatDefinition *format;
g_return_val_if_fail (nick != NULL, 0);
walk = _gst_formats;
while (walk) {
format = (GstFormatDefinition *) walk->data;
if (!strcmp (format->nick, nick))
return format->value;
walk = g_list_next (walk);
}
return GST_FORMAT_UNDEFINED;
}
/**
* gst_format_get_details:
* @format: The format to get details of
* @nick: The nick of the format
* @description: The description of the format
*
* Get details about the given format.
*
* Returns: TRUE if the format was registered, FALSE otherwise
*/
gboolean
gst_format_get_details (GstFormat format, const gchar **nick, const gchar **description)
{
GList *walk;
GstFormatDefinition *walk_format;
g_return_val_if_fail (nick != NULL, FALSE);
g_return_val_if_fail (description != NULL, FALSE);
walk = _gst_formats;
while (walk) {
walk_format = (GstFormatDefinition *) walk->data;
if (walk_format->value == format) {
*nick = walk_format->nick;
*description = walk_format->description;
return TRUE;
}
walk = g_list_next (walk);
}
return FALSE;
}

View file

@ -2,7 +2,8 @@
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wim.taymans@chello.be>
*
* gstformat.h: Header for GstFormat types of offset
* gstformat.h: Header for GstFormat types used in queries and
* seeking.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
@ -29,14 +30,14 @@
G_BEGIN_DECLS
typedef enum {
GST_FORMAT_NONE = 0,
GST_FORMAT_DEFAULT = 1,
GST_FORMAT_BYTES = 2,
GST_FORMAT_TIME = 3,
GST_FORMAT_BUFFERS = 4,
GST_FORMAT_PERCENT = 5,
GST_FORMAT_UNDEFINED = 0,
GST_FORMAT_DEFAULT = 1,
GST_FORMAT_BYTES = 2,
GST_FORMAT_TIME = 3,
GST_FORMAT_BUFFERS = 4,
GST_FORMAT_PERCENT = 5,
/* samples for audio, frames/fields for video */
GST_FORMAT_UNITS = 6,
GST_FORMAT_UNITS = 6,
} GstFormat;
#define GST_FORMATS_FUNCTION(functionname, a...) \
@ -50,6 +51,16 @@ functionname (GstPad *pad) \
return formats; \
}
void _gst_format_initialize (void);
/* register a new format */
GstFormat gst_format_register (const gchar *nick, const gchar *description);
GstFormat gst_format_get_by_nick (const gchar *nick);
/* query for format details */
gboolean gst_format_get_details (GstFormat format, const gchar **nick, const gchar **description);
G_END_DECLS