tools/iaudio.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2005 by Christian Gmeiner
  11  *
  12  * This particular source code file is licensed under the X11 license. See the
  13  * bottom of the COPYING file for details on this license.
  14  *
  15  ****************************************************************************/
  16
  17 /* This little application updates the checksum of a modifized iAudio x5
  18    firmware bin.
  19    And this is how it works:
  20
  21    The byte at offset 0x102b contains the 8-bit sum of all the bytes starting with the one at 0x1030.
  22 */
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #define CHECKSUM_BIT    0x102b
  29 #define CHECKSUM_START  0x1030
  30
  31 void usage(void) {
  32
  33     printf("usage: iaudio <input file> <output file>\n");
  34     printf("\n\nThis tool updates the checksum of an iaudio fw bin\n");
  35     exit(1);
  36 }
  37
  38 int main (int argc, char* argv[]) {
  39
  40     char byte = '\0';
  41     char checksum = '\0';
  42     unsigned long length, i;
  43     unsigned char* inbuf;
  44     unsigned char* iname = argv[1];
  45     unsigned char* oname = argv[2];
  46     FILE* pFile;
  47
  48     if (argc < 2) {
  49         usage();
  50     }
  51
  52     /* open file */
  53     pFile = fopen(iname,"rb");
  54     if (!pFile) {
  55        perror(oname);
  56        return -1;
  57     }
  58
  59     /* print old checksum */
  60     fseek (pFile, CHECKSUM_BIT, SEEK_SET);
  61     byte = fgetc(pFile);
  62     printf("Old checksum: 0x%02x\n", byte & 0xff);
  63
  64     /* get file size*/
  65     fseek(pFile,0,SEEK_END);
  66     length = ftell(pFile);
  67     fseek(pFile,0,SEEK_SET);
  68
  69     /* try to allocate memory */
  70     inbuf = malloc(length);
  71     if (!inbuf) {
  72        printf("out of memory!\n");
  73        return -1;
  74     }
  75
  76     /* read file */
  77     i = fread(inbuf, 1, length, pFile);
  78     if (!i) {
  79        perror(iname);
  80        return -1;
  81     }
  82     fclose(pFile);
  83
  84     /* calculate new checksum */
  85     for (i = CHECKSUM_START; i < length; i++) {
  86         checksum += inbuf[i];
  87     }
  88     printf("New checksum: 0x%02x\n", checksum & 0xff);
  89
  90     /* save new checksum */
  91     inbuf[CHECKSUM_BIT] = (unsigned char) checksum;
  92
  93     /* save inbuf */
  94     pFile = fopen(oname,"wb");
  95     if (!pFile) {
  96        perror(oname);
  97        return -1;
  98     }
  99
 100     i = fwrite(inbuf, 1, length, pFile);
 101     if (!i) {
 102         perror(oname);
 103         return -1;
 104     }
 105     fclose(pFile);
 106
 107     return 0;
 108 }