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 <stdio.h>
13#if HAVE_UNISTD_H
14#include <unistd.h>
15#endif
16#include <string.h>
17#include <time.h>
18
19#include "ext2_fs.h"
20#include "ext2fs.h"
21
22/*
23 * This function returns 1 if the inode's block entries actually
24 * contain block entries.
25 */
26int ext2fs_inode_has_valid_blocks(struct ext2_inode *inode)
27{
28	/*
29	 * Only directories, regular files, and some symbolic links
30	 * have valid block entries.
31	 */
32	if (!LINUX_S_ISDIR(inode->i_mode) && !LINUX_S_ISREG(inode->i_mode) &&
33	    !LINUX_S_ISLNK(inode->i_mode))
34		return 0;
35
36	/*
37	 * If the symbolic link is a "fast symlink", then the symlink
38	 * target is stored in the block entries.
39	 */
40	if (LINUX_S_ISLNK (inode->i_mode)) {
41		if (inode->i_file_acl == 0) {
42			/* With no EA block, we can rely on i_blocks */
43			if (inode->i_blocks == 0)
44				return 0;
45		} else {
46			/* With an EA block, life gets more tricky */
47			if (inode->i_size >= EXT2_N_BLOCKS*4)
48				return 1; /* definitely using i_block[] */
49			if (inode->i_size > 4 && inode->i_block[1] == 0)
50				return 1; /* definitely using i_block[] */
51			return 0; /* Probably a fast symlink */
52		}
53	}
54	return 1;
55}
56