xref: /freebsd/usr.sbin/fstyp/befs.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2021 Miguel Gocobachi
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  */
29 
30 #include <sys/cdefs.h>
31 #include <stdint.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 
36 #include "fstyp.h"
37 
38 #define B_OS_NAME_LENGTH	32
39 #define BEFS_BLOCK_OFFSET	512
40 #define BEFS_SUPER_BLOCK_MAGIC1	0x42465331
41 
42 struct disk_super_block {
43     char	name[B_OS_NAME_LENGTH];
44     int32_t	magic1;
45 };
46 
47 int
48 fstyp_befs(FILE *fp, char *label, size_t size)
49 {
50 	struct disk_super_block *volume;
51 
52 	volume = read_buf(fp, BEFS_BLOCK_OFFSET, sizeof(*volume));
53 
54 	if (volume == NULL) {
55 		return (1);
56 	}
57 
58 	if (volume->magic1 == BEFS_SUPER_BLOCK_MAGIC1) {
59 		strlcpy(label, volume->name, size);
60 		free(volume);
61 
62 		return (0);
63 	}
64 
65 	free(volume);
66 
67 	return (1);
68 }
69