apps/metadata/vorbis.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2005 Dave Chapman
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #include <ctype.h>
  25 #include <inttypes.h>
  26
  27 #include "system.h"
  28 #include "metadata.h"
  29 #include "metadata_common.h"
  30 #include "metadata_parsers.h"
  31 #include "structec.h"
  32 #include "logf.h"
  33
  34 /* Read the items in a Vorbis comment packet. Returns true the items were
  35  * fully read, false otherwise.
  36  */
  37 bool read_vorbis_tags(int fd, struct mp3entry *id3,
  38     long tag_remaining)
  39 {
  40     char *buf = id3->id3v2buf;
  41     int32_t comment_count;
  42     int32_t len;
  43     int buf_remaining = sizeof(id3->id3v2buf) + sizeof(id3->id3v1buf);
  44     int i;
  45
  46     if (ecread(fd, &len, 1, "l", IS_BIG_ENDIAN) < (long) sizeof(len))
  47     {
  48         return false;
  49     }
  50
  51     if ((lseek(fd, len, SEEK_CUR) < 0)
  52         || (ecread(fd, &comment_count, 1, "l", IS_BIG_ENDIAN)
  53             < (long) sizeof(comment_count)))
  54     {
  55         return false;
  56     }
  57
  58     tag_remaining -= len + sizeof(len) + sizeof(comment_count);
  59
  60     if (tag_remaining <= 0)
  61     {
  62         return true;
  63     }
  64
  65     for (i = 0; i < comment_count; i++)
  66     {
  67         char name[TAG_NAME_LENGTH];
  68         char value[TAG_VALUE_LENGTH];
  69         int32_t read_len;
  70
  71         if (tag_remaining < 4)
  72         {
  73             break;
  74         }
  75
  76         if (ecread(fd, &len, 1, "l", IS_BIG_ENDIAN) < (long) sizeof(len))
  77         {
  78             return false;
  79         }
  80
  81         tag_remaining -= 4;
  82
  83         /* Quit if we've passed the end of the page */
  84         if (tag_remaining < len)
  85         {
  86             break;
  87         }
  88
  89         tag_remaining -= len;
  90         read_len = read_string(fd, name, sizeof(name), '=', len);
  91
  92         if (read_len < 0)
  93         {
  94             return false;
  95         }
  96
  97         len -= read_len;
  98
  99         if (read_string(fd, value, sizeof(value), -1, len) < 0)
 100         {
 101             return false;
 102         }
 103
 104         len = parse_tag(name, value, id3, buf, buf_remaining,
 105             TAGTYPE_VORBIS);
 106         buf += len;
 107         buf_remaining -= len;
 108     }
 109
 110     /* Skip to the end of the block */
 111     if (tag_remaining)
 112     {
 113         if (lseek(fd, tag_remaining, SEEK_CUR) < 0)
 114         {
 115             return false;
 116         }
 117     }
 118
 119     return true;
 120 }