gstreamer/gst/gstformat.c
Iain Holmes 4b93f5a554 Use some hashtables instead of a linked list
Original commit message from CVS:
Use some hashtables instead of a linked list
2002-09-29 17:17:28 +00:00

150 lines
4.1 KiB
C

/* 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 <string.h>
#include "gstlog.h"
#include "gstformat.h"
static GList *_gst_formats = NULL;
static GHashTable *_nick_to_format = NULL;
static GHashTable *_format_to_nick = NULL;
static gint _n_values = 1; /* we start from 1 because 0 reserved for UNDEFINED */
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;
if (_nick_to_format == NULL) {
_nick_to_format = g_hash_table_new (g_str_hash, g_str_equal);
_format_to_nick = g_hash_table_new (NULL, NULL);
}
while (standards->nick) {
g_hash_table_insert (_nick_to_format, standards->nick, standards);
g_hash_table_insert (_format_to_nick, GINT_TO_POINTER (standards->value), standards);
_gst_formats = g_list_append (_gst_formats, standards);
standards++;
_n_values++;
}
}
/**
* 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);
g_hash_table_insert (_nick_to_format, format->nick, format);
g_hash_table_insert (_format_to_nick, GINT_TO_POINTER (format->value), format);
_gst_formats = g_list_append (_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)
{
GstFormatDefinition *format;
g_return_val_if_fail (nick != NULL, 0);
format = g_hash_table_lookup (_nick_to_format, nick);
if (format != NULL)
return format->value;
else
return GST_FORMAT_UNDEFINED;
}
/**
* gst_format_get_details:
* @format: The format to get details of
*
* Get details about the given format.
*
* Returns: The #GstFormatDefinition for @format or NULL on failure.
*/
const GstFormatDefinition *
gst_format_get_details (GstFormat format)
{
return g_hash_table_lookup (_format_to_nick, GINT_TO_POINTER (format));
}
/**
* gst_format_get_definitions:
*
* Get a list of all the registered formats.
*
* Returns: A GList of #GstFormatDefinition.
*/
const GList *
gst_format_get_definitions (void)
{
return _gst_formats;
}