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udevadm: add --version --help options to man page, hide them as commands
[elogind.git] / extras / volume_id / lib / ddf_raid.c
1 /*
2  * volume_id - reads filesystem label and uuid
3  *
4  * Copyright (C) 2007 Kay Sievers <kay.sievers@vrfy.org>
5  *
6  *      This program is free software; you can redistribute it and/or modify it
7  *      under the terms of the GNU General Public License as published by the
8  *      Free Software Foundation version 2 of the License.
9  */
10
11 #ifndef _GNU_SOURCE
12 #define _GNU_SOURCE 1
13 #endif
14
15 #ifdef HAVE_CONFIG_H
16 #  include <config.h>
17 #endif
18
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <unistd.h>
22 #include <string.h>
23 #include <errno.h>
24 #include <ctype.h>
25 #include <byteswap.h>
26
27 #include "libvolume_id.h"
28 #include "libvolume_id-private.h"
29 #include "util.h"
30
31 /* http://www.snia.org/standards/home */
32
33 #define DDF_HEADER                      0xDE11DE11
34 #define DDF_GUID_LENGTH                 24
35 #define DDF_REV_LENGTH                  8
36
37 struct ddf_header {
38         uint32_t        signature;
39         uint32_t        crc;
40         uint8_t         guid[DDF_GUID_LENGTH];
41         uint8_t         ddf_rev[DDF_REV_LENGTH];
42 } PACKED;
43
44 int volume_id_probe_ddf_raid(struct volume_id *id, uint64_t off, uint64_t size)
45 {
46         uint64_t ddf_off = ((size / 0x200)-1) * 0x200;
47         const uint8_t *buf;
48         struct ddf_header *ddf;
49
50         info("probing at offset 0x%llx, size 0x%llx\n",
51             (unsigned long long) off, (unsigned long long) size);
52         if (size < 0x10000)
53                 return -1;
54
55         buf = volume_id_get_buffer(id, off + ddf_off, 0x200);
56         if (buf == NULL)
57                 return -1;
58         ddf = (struct ddf_header *) buf;
59
60         if (ddf->signature != cpu_to_be32(DDF_HEADER))
61                 return -1;
62
63         volume_id_set_uuid(id, ddf->guid, DDF_GUID_LENGTH, UUID_STRING);
64         snprintf(id->type_version, DDF_REV_LENGTH, "%s", ddf->ddf_rev);
65         volume_id_set_usage(id, VOLUME_ID_RAID);
66         id->type = "ddf_raid_member";
67         return 0;
68 }