Function comp_FAT

src/fat.c:883–939

}

int comp_FAT(disk_t *disk, const partition_t *partition, const unsigned long int fat_size, const unsigned long int sect_res)
{
  /*
  return 0 if FATs match
  */
  unsigned int reste;
  uint64_t hd_offset;
  uint64_t hd_offset2;
  unsigned char *buffer;
  unsigned char *buffer2;
  buffer=(unsigned char *)MALLOC(16*disk->sector_size);
  buffer2=(unsigned char *)MALLOC(16*disk->sector_size);
  hd_offset=partition->part_offset+(uint64_t)sect_res*disk->sector_size;
  hd_offset2=hd_offset+(uint64_t)fat_size*disk->sector_size;
  reste=(fat_size>1000?1000:fat_size); /* Quick check ! */
  reste*=disk->sector_size;
  while(reste>0)
  {
    const unsigned int read_size=(reste > 16 * disk->sector_size ? 16 * disk->sector_size :reste);
    reste-=read_size;
    if((unsigned)disk->pread(disk, buffer, read_size, hd_offset) != read_size)
    {
#ifndef DISABLED_FOR_FRAMAC
      log_error("comp_FAT: can't read FAT1\n");
#endif
      free(buffer2);
      free(buffer);
      return 1;
    }
    if((unsigned)disk->pread(disk, buffer2, read_size, hd_offset2) != read_size)
    {
#ifndef DISABLED_FOR_FRAMAC
      log_error("comp_FAT: can't read FAT2\n");
#endif
      free(buffer2);
      free(buffer);
      return 1;
    }
    if(memcmp(buffer, buffer2, read_size)!=0)
    {
#ifndef DISABLED_FOR_FRAMAC
      log_error("FAT differs, FAT sectors=%lu-%lu/%lu\n",
          (unsigned long) ((hd_offset-partition->part_offset)/disk->sector_size-sect_res),
          (unsigned long) ((hd_offset-partition->part_offset+read_size)/disk->sector_size-sect_res),
          fat_size);
#endif
      free(buffer2);
      free(buffer);
      return 1;
    }
    hd_offset+=read_size;
    hd_offset2+=read_size;
  }
  free(buffer2);
  free(buffer);
  return 0;
}