xref: /dflybsd-src/lib/libfsid/ext2.c (revision 1e642749c8bd45bb028f6631287095a2ba4cef6d)
1 /*
2  * Copyright (c) 2010 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Ákos Kovács <akoskovacs@gmx.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 #include "libfsid.h"
35 #include <vfs/gnu/ext2fs/ext2_fs.h>
36 #include <vfs/gnu/ext2fs/fs.h>
37 
38 static char buffer[sizeof(struct ext2_super_block)*2];
39 
40 int
41 ext2_probe(const char *dev)
42 {
43 	static struct ext2_super_block *fs;
44 
45 	if (fsid_dev_read(dev, SBOFF, sizeof(buffer), buffer) != 0)
46 		return 0;
47 
48 	fs = (struct ext2_super_block *)&buffer;
49 
50 	if (fs->s_magic == EXT2_SUPER_MAGIC)
51 		return 1;
52 
53 	return 0;
54 }
55 
56 char *
57 ext2_volname(const char *dev)
58 {
59 	static struct ext2_super_block *fs;
60 
61 	if (fsid_dev_read(dev, SBOFF, sizeof(buffer), buffer) != 0)
62 		return NULL;
63 
64 	fs = (struct ext2_super_block *)&buffer;
65 
66 	if (fs->s_magic != EXT2_SUPER_MAGIC)
67 		return NULL;
68 
69 	if (fs->s_volume_name[0] == '\0')
70 		return NULL;
71 
72 	fs->s_volume_name[15] = '\0';
73 		return fs->s_volume_name;
74 }
75