Function ntfs_remove_used_space

src/ntfsp.c:65–160

#define SIZEOF_BUFFER ((const unsigned int)512)

unsigned int ntfs_remove_used_space(disk_t *disk_car,const partition_t *partition, alloc_data_t *list_search_space)
{
  dir_data_t dir_data;
  switch(dir_partition_ntfs_init(disk_car, partition, &dir_data, 0, 0))
  {
    case DIR_PART_ENOIMP:
    case DIR_PART_ENOSYS:
      return 0;
    case DIR_PART_EIO:
      log_partition(disk_car,partition);
      log_error("Can't open filesystem. Filesystem seems damaged.\n");
      return 0;
    case DIR_PART_OK:
      break;
  }
  {
    struct ntfs_dir_struct *ls=(struct ntfs_dir_struct *)dir_data.private_dir_data;
    unsigned char *buffer;
    uint64_t start_free=0;
    uint64_t end_free=0;
    unsigned long int lcn;
    unsigned long int no_of_cluster;
    unsigned int cluster_size;	/* size in bytes */
    /* Which bit of $Bitmap is in the buffer */
    long long int bmplcn = - (SIZEOF_BUFFER << 3);
    log_trace("ntfs_remove_used_space\n");
    buffer=(unsigned char *)MALLOC(SIZEOF_BUFFER);
    {
      const struct ntfs_boot_sector*ntfs_header=(const struct ntfs_boot_sector*)buffer;
      if(disk_car->pread(disk_car, buffer, 512, partition->part_offset) != 512)
      {
	free(buffer);
	dir_data.close(&dir_data);
	return 0;
      }
      cluster_size=ntfs_header->sectors_per_cluster*ntfs_sector_size(ntfs_header);
      if(cluster_size==0)
      {
	free(buffer);
	dir_data.close(&dir_data);
	return 0;
      }
      no_of_cluster=(le64(ntfs_header->sectors_nbr) < partition->part_size ? le64(ntfs_header->sectors_nbr) : partition->part_size);
      no_of_cluster/=ntfs_header->sectors_per_cluster;
    }
    for(lcn=0;lcn<no_of_cluster;lcn++)
    {
      int byte, bit;
      if ((bmplcn < 0) || (lcn < (unsigned)bmplcn) || (lcn >= ((unsigned)bmplcn + (SIZEOF_BUFFER << 3))))
      {
	ntfs_attr *attr;
	/* Mark the buffer as not in use, in case the read is shorter. */
	memset(buffer, 0x00, SIZEOF_BUFFER);
	bmplcn = lcn & (~((SIZEOF_BUFFER << 3) - 1));
	attr = ntfs_attr_open(ls->vol->lcnbmp_ni, AT_DATA, AT_UNNAMED, 0);
	if(attr==NULL)
	{
	  log_error("Couldn't open $Bitmap\n");