1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
/*
* Get label. Used by both mount and umount.
*/
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include "linux_fs.h"
#include "get_label_uuid.h"
/*
* See whether this device has (the magic of) a RAID superblock at the end.
* If so, it probably is, or has been, part of a RAID array.
*
* For the moment this test is switched off - it causes problems.
* "Checking for a disk label should only be done on the full raid,
* not on the disks that form the raid array. This test causes a lot of
* problems when run on my striped promise fasttrak 100 array."
*/
static inline int
is_raid_partition(int fd) {
#if 0
struct mdp_super_block mdsb;
int n;
/* hardcode 4096 here in various places, because that's
what it's defined to be. Note that even if we used
the actual kernel headers, sizeof(mdp_super_t) is
slightly larger in the 2.2 kernel on 64-bit archs,
so using that wouldn't work. */
lseek(fd, -4096, SEEK_END); /* Ignore possible error
about return value overflow */
n = 4096;
if (sizeof(mdsb) < n)
n = sizeof(mdsb);
if (read(fd, &mdsb, n) != n)
return 1; /* error */
return (mdsbmagic(mdsb) == MD_SB_MAGIC);
#else
return 0;
#endif
}
/* for now, only ext2, ext3, xfs, ocfs are supported */
int
get_label_uuid(const char *device, char **label, char *uuid) {
int fd;
int rv = 1;
size_t namesize;
struct ext2_super_block e2sb;
struct xfs_super_block xfsb;
struct jfs_super_block jfssb;
struct ocfs_volume_header ovh; /* Oracle */
struct ocfs_volume_label olbl;
fd = open(device, O_RDONLY);
if (fd < 0)
return rv;
/* If there is a RAID partition, or an error, ignore this partition */
if (is_raid_partition(fd)) {
close(fd);
return rv;
}
if (lseek(fd, 1024, SEEK_SET) == 1024
&& read(fd, (char *) &e2sb, sizeof(e2sb)) == sizeof(e2sb)
&& (ext2magic(e2sb) == EXT2_SUPER_MAGIC)) {
memcpy(uuid, e2sb.s_uuid, sizeof(e2sb.s_uuid));
namesize = sizeof(e2sb.s_volume_name);
if ((*label = calloc(namesize + 1, 1)) != NULL)
memcpy(*label, e2sb.s_volume_name, namesize);
rv = 0;
}
else if (lseek(fd, 0, SEEK_SET) == 0
&& read(fd, (char *) &xfsb, sizeof(xfsb)) == sizeof(xfsb)
&& (strncmp(xfsb.s_magic, XFS_SUPER_MAGIC, 4) == 0)) {
memcpy(uuid, xfsb.s_uuid, sizeof(xfsb.s_uuid));
namesize = sizeof(xfsb.s_fname);
if ((*label = calloc(namesize + 1, 1)) != NULL)
memcpy(*label, xfsb.s_fname, namesize);
rv = 0;
}
else if (lseek(fd, 0, SEEK_SET) == 0
&& read(fd, (char *) &ovh, sizeof(ovh)) == sizeof(ovh)
&& (strncmp(ovh.signature, OCFS_MAGIC, sizeof(OCFS_MAGIC)) == 0)
&& (lseek(fd, 512, SEEK_SET) == 512)
&& read(fd, (char *) &olbl, sizeof(olbl)) == sizeof(olbl)) {
uuid[0] = '\0';
namesize = ocfslabellen(olbl);
if ((*label = calloc(namesize + 1, 1)) != NULL)
memcpy(*label, olbl.label, namesize);
rv = 0;
}
else if (lseek(fd, JFS_SUPER1_OFF, SEEK_SET) == JFS_SUPER1_OFF
&& read(fd, (char *) &jfssb, sizeof(jfssb)) == sizeof(jfssb)
&& (strncmp(jfssb.s_magic, JFS_MAGIC, 4) == 0)) {
if (assemble4le(jfssb.s_version) == 1) {
/* old (OS/2 compatible) jfs filesystems don't
have UUIDs and only have a very small label. */
memset(uuid, 0, 16);
namesize = sizeof(jfssb.s_fpack);
if ((*label = calloc(namesize + 1, 1)) != NULL)
memcpy(*label, jfssb.s_fpack, namesize);
} else {
memcpy(uuid, jfssb.s_uuid, sizeof(jfssb.s_uuid));
namesize = sizeof(jfssb.s_label);
if ((*label = calloc(namesize + 1, 1)) != NULL)
memcpy(*label, jfssb.s_label, namesize);
}
rv = 0;
}
close(fd);
return rv;
}
|
