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
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <stdlib.h>
#ifdef HAVE_BLKID_BLKID_H
#include <blkid/blkid.h>
#else
#include <blkid.h>
#endif
#include "blkdev.h"
#include "canonicalize.h"
#include "pathnames.h"
#include "fsprobe.h"
static blkid_cache blcache;
#ifdef HAVE_BLKID_EVALUATE_TAG
/* ask kernel developers why we need such ugly open() method... */
static int
open_device(const char *devname)
{
int retries = 0;
do {
int fd = open(devname, O_RDONLY);
if (fd >= 0)
return fd;
#ifdef ENOMEDIUM
/* ENOMEDIUM is Linux-only */
if (errno != ENOMEDIUM)
break;
#else
break;
#endif
if (retries >= CRDOM_NOMEDIUM_RETRIES)
break;
++retries;
sleep(3);
} while(1);
return -1;
}
#endif
/*
* Parses NAME=value, returns -1 on parse error, 0 success. The success is also
* when the 'spec' doesn't contain name=value pair (because the spec could be
* a devname too). In particular case the pointer 'name' is set to NULL.
*/
int
fsprobe_parse_spec(const char *spec, char **name, char **value)
{
*name = NULL;
*value = NULL;
if (strchr(spec, '='))
return blkid_parse_tag_string(spec, name, value);
return 0;
}
char *
fsprobe_get_devname_by_spec(const char *spec)
{
char *name, *value;
if (!spec)
return NULL;
if (fsprobe_parse_spec(spec, &name, &value) != 0)
return NULL; /* parse error */
if (name) {
char *nspec = NULL;
if (!strcmp(name,"LABEL"))
nspec = fsprobe_get_devname_by_label(value);
else if (!strcmp(name,"UUID"))
nspec = fsprobe_get_devname_by_uuid(value);
free(name);
free(value);
return nspec;
}
return canonicalize_path(spec);
}
void
fsprobe_init(void)
{
blcache = NULL;
}
int
fsprobe_known_fstype(const char *fstype)
{
return blkid_known_fstype(fstype);
}
#ifdef HAVE_BLKID_EVALUATE_TAG
/*
* libblkid from util-linux-ng
* -- recommended
*/
static blkid_probe blprobe;
void
fsprobe_exit(void)
{
if (blprobe)
blkid_free_probe(blprobe);
if (blcache)
blkid_put_cache(blcache);
}
/* returns device LABEL, UUID, FSTYPE, ... by low-level
* probing interface
*/
static char *
fsprobe_get_value(const char *name, const char *devname)
{
int fd;
const char *data = NULL;
if (!devname || !name)
return NULL;
fd = open_device(devname);
if (fd < 0)
return NULL;
if (!blprobe)
blprobe = blkid_new_probe();
if (!blprobe)
goto done;
if (blkid_probe_set_device(blprobe, fd, 0, 0))
goto done;
if (blkid_probe_set_request(blprobe, BLKID_PROBREQ_LABEL |
BLKID_PROBREQ_UUID | BLKID_PROBREQ_TYPE ))
goto done;
if (blkid_do_safeprobe(blprobe))
goto done;
if (blkid_probe_lookup_value(blprobe, name, &data, NULL))
goto done;
done:
close(fd);
return data ? strdup((char *) data) : NULL;
}
char *
fsprobe_get_label_by_devname(const char *devname)
{
return fsprobe_get_value("LABEL", devname);
}
char *
fsprobe_get_uuid_by_devname(const char *devname)
{
return fsprobe_get_value("UUID", devname);
}
char *
fsprobe_get_fstype_by_devname(const char *devname)
{
return fsprobe_get_value("TYPE", devname);
}
char *
fsprobe_get_devname_by_uuid(const char *uuid)
{
return blkid_evaluate_tag("UUID", uuid, &blcache);
}
char *
fsprobe_get_devname_by_label(const char *label)
{
return blkid_evaluate_tag("LABEL", label, &blcache);
}
#else /* !HAVE_BLKID_EVALUATE_TAG */
/*
* Classic libblkid (from e2fsprogs) without blkid_evaluate_tag()
* -- deprecated
*/
#define BLKID_EMPTY_CACHE "/dev/null"
void
fsprobe_exit(void)
{
if (blcache)
blkid_put_cache(blcache);
}
char *
fsprobe_get_devname_by_uuid(const char *uuid)
{
if (!blcache)
blkid_get_cache(&blcache, NULL);
return blkid_get_devname(blcache, "UUID", uuid);
}
char *
fsprobe_get_devname_by_label(const char *label)
{
if (!blcache)
blkid_get_cache(&blcache, NULL);
return blkid_get_devname(blcache, "LABEL", label);
}
char *
fsprobe_get_fstype_by_devname(const char *devname)
{
blkid_cache c;
char *tp;
if (blcache)
return blkid_get_tag_value(blcache, "TYPE", devname);
/* The cache is not initialized yet. Use empty cache rather than waste
* time with /etc/blkid.tab. It seems that probe FS is faster than
* parse the cache file. -- kzak (17-May-2007)
*/
blkid_get_cache(&c, BLKID_EMPTY_CACHE);
tp = blkid_get_tag_value(c, "TYPE", devname);
blkid_put_cache(c);
return tp;
}
char *
fsprobe_get_label_by_devname(const char *devname)
{
if (!blcache)
blkid_get_cache(&blcache, NULL);
return blkid_get_tag_value(blcache, "LABEL", devname);
}
char *
fsprobe_get_uuid_by_devname(const char *devname)
{
if (!blcache)
blkid_get_cache(&blcache, NULL);
return blkid_get_tag_value(blcache, "UUID", devname);
}
#endif /* !HAVE_BLKID_EVALUATE_TAG */
|
