Function create_fat_boot_sector

src/fat_adv.c:1062–1261

}

static void create_fat_boot_sector(disk_t *disk_car, partition_t *partition, const unsigned int reserved, const int verbose, const unsigned int dir_entries, const unsigned long int root_cluster, const unsigned int sectors_per_cluster, const unsigned int fat_length, const upart_type_t upart_type, const unsigned int fats, char **current_cmd)
{
  unsigned char *orgboot;
  unsigned char *newboot;
  const struct fat_boot_sector *org_fat_header;
  struct fat_boot_sector *fat_header;
  int error=0;
  unsigned long int part_size=0;
  orgboot=(unsigned char *)MALLOC(3*disk_car->sector_size);
  newboot=(unsigned char *)MALLOC(3*disk_car->sector_size);
  org_fat_header=(const struct fat_boot_sector *)orgboot;
  fat_header=(struct fat_boot_sector *)newboot;
  if((unsigned)disk_car->pread(disk_car, orgboot, 3 * disk_car->sector_size, partition->part_offset) != 3 * disk_car->sector_size)
  {
    log_error("create_fat_boot_sector: Can't read old boot sector\n");
    memset(orgboot,0,3*disk_car->sector_size);
  }
  memcpy(newboot,orgboot,3*disk_car->sector_size);
  if(3*disk_car->sector_size >= DEFAULT_SECTOR_SIZE &&
      (le16(fat_header->marker)!=0xAA55 ||
       !((fat_header->ignored[0]==0xeb && fat_header->ignored[2]==0x90)||fat_header->ignored[0]==0xe9)))
  {
    write_FAT_boot_code_aux(newboot);
  }
  fat_header->sector_size[0]=disk_car->sector_size & 0xFF;
  fat_header->sector_size[1]=disk_car->sector_size >>8;
  fat_header->fats=fats;
  fat_header->secs_track=le16(disk_car->geom.sectors_per_head);
  fat_header->heads=le16(disk_car->geom.heads_per_cylinder);
  fat_header->marker=le16(0xAA55);
  if(!((fat_header->ignored[0]==0xeb&&fat_header->ignored[2]==0x90)||fat_header->ignored[0]==0xe9))
  {
    fat_header->ignored[0]=0xeb;
    fat_header->ignored[2]=0x90;
  }

  /* I have seen a FAT32 partition that Win98 2nd edition was unable to read
   * because this name was missing! */
  if(memcmp(fat_header->system_id,"MSDOS5.0",8) &&
      memcmp(fat_header->system_id,"MSWIN4.0",8) &&
      memcmp(fat_header->system_id,"MSWIN4.1",8))
    memcpy(fat_header->system_id,"MSWIN4.1",8);
  /* FIXME, need to know where the extended or logical partition start */
#if 0
  if(partition->status==STATUS_LOG)
    fat_header->hidden=le32(disk_car->geom.sectors_per_head);
  else
#endif
    fat_header->hidden=le32((partition->part_offset/disk_car->sector_size));
  fat_header->sectors_per_cluster=sectors_per_cluster;
  fat_header->reserved=le16(reserved);
  /* The filesystem size can be smaller than the partition size */
  switch(upart_type)
  {
    case UP_FAT12:
      part_size=le16(fat_header->reserved)+fats*fat_length+dir_entries*32/disk_car->sector_size+sectors_per_cluster*(fat_length*disk_car->sector_size*2/3-2);
      break;
    case UP_FAT16: