apps/metadata/sid.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2005 Dave Chapman
  11  *
  12  * All files in this archive are subject to the GNU General Public License.
  13  * See the file COPYING in the source tree root for full license agreement.
  14  *
  15  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  16  * KIND, either express or implied.
  17  *
  18  ****************************************************************************/
  19 #include <stdio.h>
  20 #include <string.h>
  21 #include <stdlib.h>
  22 #include <ctype.h>
  23 #include <inttypes.h>
  24
  25 #include "system.h"
  26 #include "id3.h"
  27 #include "metadata_common.h"
  28 #include "atoi.h"
  29 #include "rbunicode.h"
  30
  31 /* PSID metadata info is available here:
  32    http://www.unusedino.de/ec64/technical/formats/sidplay.html */
  33 bool get_sid_metadata(int fd, struct mp3entry* id3)
  34 {
  35     /* Use the trackname part of the id3 structure as a temporary buffer */
  36     unsigned char* buf = (unsigned char *)id3->path;
  37     int read_bytes;
  38     char *p;
  39
  40
  41     if ((lseek(fd, 0, SEEK_SET) < 0)
  42          || ((read_bytes = read(fd, buf, 0x80)) < 0x80))
  43     {
  44         return false;
  45     }
  46
  47     if ((memcmp(buf, "PSID",4) != 0))
  48     {
  49         return false;
  50     }
  51
  52     p = id3->id3v2buf;
  53
  54     /* Copy Title (assumed max 0x1f letters + 1 zero byte) */
  55     id3->title = p;
  56     buf[0x16+0x1f] = 0;
  57     p = iso_decode(&buf[0x16], p, 0, strlen(&buf[0x16])+1);
  58
  59     /* Copy Artist (assumed max 0x1f letters + 1 zero byte) */
  60     id3->artist = p;
  61     buf[0x36+0x1f] = 0;
  62     p = iso_decode(&buf[0x36], p, 0, strlen(&buf[0x36])+1);
  63
  64     /* Copy Year (assumed max 4 letters + 1 zero byte) */
  65     buf[0x56+0x4] = 0;
  66     id3->year = atoi(&buf[0x56]);
  67
  68     /* Copy Album (assumed max 0x1f-0x05 letters + 1 zero byte) */
  69     id3->album = p;
  70     buf[0x56+0x1f] = 0;
  71     p = iso_decode(&buf[0x5b], p, 0, strlen(&buf[0x5b])+1);
  72
  73     id3->bitrate = 706;
  74     id3->frequency = 44100;
  75     /* New idea as posted by Marco Alanen (ravon):
  76      * Set the songlength in seconds to the number of subsongs
  77      * so every second represents a subsong.
  78      * Users can then skip the current subsong by seeking
  79      *
  80      * Note: the number of songs is a 16bit value at 0xE, so this code only
  81      * uses the lower 8 bits of the counter.
  82     */
  83     id3->length = (buf[0xf]-1)*1000;
  84     id3->vbr = false;
  85     id3->filesize = filesize(fd);
  86
  87     return true;
  88 }