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 
do_dump_unused(int argc EXT2FS_ATTR ((unused)),char ** argv)27 void do_dump_unused(int argc EXT2FS_ATTR((unused)), char **argv)
28 {
29 	blk64_t		blk;
30 	unsigned char	buf[EXT2_MAX_BLOCK_SIZE];
31 	unsigned int	i;
32 	errcode_t	retval;
33 
34 	if (common_args_process(argc, argv, 1, 1,
35 				"dump_unused", "", 0))
36 		return;
37 
38 	for (blk=current_fs->super->s_first_data_block;
39 	     blk < ext2fs_blocks_count(current_fs->super); blk++) {
40 		if (ext2fs_test_block_bitmap2(current_fs->block_map,blk))
41 			continue;
42 		retval = io_channel_read_blk64(current_fs->io, blk, 1, buf);
43 		if (retval) {
44 			com_err(argv[0], retval, "While reading block\n");
45 			return;
46 		}
47 		for (i=0; i < current_fs->blocksize; i++)
48 			if (buf[i])
49 				break;
50 		if (i >= current_fs->blocksize)
51 			continue;
52 		printf("\nUnused block %llu contains non-zero data:\n\n",
53 		       blk);
54 		for (i=0; i < current_fs->blocksize; i++)
55 			fputc(buf[i], stdout);
56 	}
57 }
58