valid_blk.c revision 0c80c44bd08c60f3cd0ad87f12a71a75cac3bcaa 
1/*
2 * valid_blk.c --- does the inode have valid blocks?
3 *
4 * Copyright 1997 by Theodore Ts'o
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12#include "config.h"
13#include <stdio.h>
14#if HAVE_UNISTD_H
15#include <unistd.h>
16#endif
17#include <string.h>
18#include <time.h>
19
20#include "ext2_fs.h"
21#include "ext2fs.h"
22
23/*
24 * This function returns 1 if the inode's block entries actually
25 * contain block entries.
26 */
27int ext2fs_inode_has_valid_blocks2(ext2_filsys fs, struct ext2_inode *inode)
28{
29	/*
30	 * Only directories, regular files, and some symbolic links
31	 * have valid block entries.
32	 */
33	if (!LINUX_S_ISDIR(inode->i_mode) && !LINUX_S_ISREG(inode->i_mode) &&
34	    !LINUX_S_ISLNK(inode->i_mode))
35		return 0;
36
37	/*
38	 * If the symbolic link is a "fast symlink", then the symlink
39	 * target is stored in the block entries.
40	 */
41	if (LINUX_S_ISLNK (inode->i_mode)) {
42		if (ext2fs_file_acl_block(fs, inode) == 0) {
43			/* With no EA block, we can rely on i_blocks */
44			if (inode->i_blocks == 0)
45				return 0;
46		} else {
47			/* With an EA block, life gets more tricky */
48			if (inode->i_size >= EXT2_N_BLOCKS*4)
49				return 1; /* definitely using i_block[] */
50			if (inode->i_size > 4 && inode->i_block[1] == 0)
51				return 1; /* definitely using i_block[] */
52			return 0; /* Probably a fast symlink */
53		}
54	}
55	return 1;
56}
57
58int ext2fs_inode_has_valid_blocks(struct ext2_inode *inode)
59{
60	return ext2fs_inode_has_valid_blocks2(NULL, inode);
61}
62