epan/codecs.c

   1 /* codecs.c
   2  * codecs interface   2007 Tomas Kukosa
   3  *
   4  * $Id$
   5  *
   6  * Wireshark - Network traffic analyzer
   7  * By Gerald Combs <gerald@wireshark.org>
   8  * Copyright 1998 Gerald Combs
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version 2
  13  * of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  23  */
  24
  25 #include "config.h"
  26
  27 #include <epan/codecs.h>
  28
  29 struct codec_handle {
  30         const char *name;
  31         codec_init_fn init_fn;
  32         codec_release_fn release_fn;
  33         codec_decode_fn decode_fn;
  34 };
  35
  36 /*
  37  * List of registered codecs.
  38  */
  39 static GHashTable *registered_codecs = NULL;
  40
  41
  42 /* Find a registered codec by name. */
  43 codec_handle_t
  44 find_codec(const char *name)
  45 {
  46         return (registered_codecs) ? (codec_handle_t)g_hash_table_lookup(registered_codecs, name) : NULL;
  47 }
  48
  49 /* Register a codec by name. */
  50 void
  51 register_codec(const char *name, codec_init_fn init_fn, codec_release_fn release_fn, codec_decode_fn decode_fn)
  52 {
  53         struct codec_handle *handle;
  54
  55         /* Create our hash table if it doesn't already exist */
  56         if (registered_codecs == NULL) {
  57                 registered_codecs = g_hash_table_new(g_str_hash, g_str_equal);
  58                 g_assert(registered_codecs != NULL);
  59         }
  60
  61         /* Make sure the registration is unique */
  62         g_assert(g_hash_table_lookup(registered_codecs, name) == NULL);
  63
  64         handle = (struct codec_handle *)g_malloc(sizeof (struct codec_handle));
  65         handle->name = name;
  66         handle->init_fn = init_fn;
  67         handle->release_fn = release_fn;
  68         handle->decode_fn = decode_fn;
  69
  70         g_hash_table_insert(registered_codecs, (gpointer)name, (gpointer) handle);
  71 }
  72
  73 void *codec_init(codec_handle_t codec)
  74 {
  75         if (!codec) return NULL;
  76         return (codec->init_fn)();
  77 }
  78
  79 void codec_release(codec_handle_t codec, void *context)
  80 {
  81         if (!codec) return;
  82         (codec->release_fn)(context);
  83 }
  84
  85 int codec_decode(codec_handle_t codec, void *context, const void *input, int inputSizeBytes, void *output, int *outputSizeBytes)
  86 {
  87         if (!codec) return 0;
  88         return (codec->decode_fn)(context, input, inputSizeBytes, output, outputSizeBytes);
  89 }