debugfs/unused.c

   1 /*
   2  * unused.c --- quick and dirty unused space dumper
   3  *
   4  * Copyright (C) 1997 Theodore Ts'o.  This file may be redistributed
   5  * under the terms of the GNU Public License.
   6  */
   7
   8 #include <stdio.h>
   9 #include <unistd.h>
  10 #include <stdlib.h>
  11 #include <ctype.h>
  12 #include <string.h>
  13 #include <time.h>
  14 #ifdef HAVE_ERRNO_H
  15 #include <errno.h>
  16 #endif
  17 #include <sys/types.h>
  18 #ifdef HAVE_GETOPT_H
  19 #include <getopt.h>
  20 #else
  21 extern int optind;
  22 extern char *optarg;
  23 #endif
  24
  25 #include "debugfs.h"
  26
  27 void do_dump_unused(int argc EXT2FS_ATTR((unused)), char **argv)
  28 {
  29         unsigned long   blk;
  30         unsigned char buf[32768];
  31         unsigned int    i;
  32         errcode_t       retval;
  33
  34         for (blk=current_fs->super->s_first_data_block;
  35              blk < current_fs->super->s_blocks_count; blk++) {
  36                 if (ext2fs_test_block_bitmap(current_fs->block_map,blk))
  37                         continue;
  38                 retval = io_channel_read_blk(current_fs->io, blk, 1, buf);
  39                 if (retval) {
  40                         com_err(argv[0], retval, "While reading block\n");
  41                         return;
  42                 }
  43                 for (i=0; i < current_fs->blocksize; i++)
  44                         if (buf[i])
  45                                 break;
  46                 if (i >= current_fs->blocksize)
  47                         continue;
  48                 printf("\nUnused block %lu contains non-zero data:\n\n",
  49                        blk);
  50                 for (i=0; i < current_fs->blocksize; i++)
  51                         fputc(buf[i], stdout);
  52         }
  53 }