1 /*
2 * devname.c --- Support function to translate a user provided string
3 * identifying a device to an actual device path
4 *
5 * Copyright (C) 2022 Red Hat, Inc., Lukas Czerner <[email protected]>
6 *
7 * %Begin-Header%
8 * This file may be redistributed under the terms of the GNU Public
9 * License.
10 * %End-Header%
11 */
12
13 #include <unistd.h>
14 #include <string.h>
15 #include <stdio.h>
16
17 #include "config.h"
18 #include "devname.h"
19 #include "nls-enable.h"
20
21 /*
22 * blkid_get_devname() is primarily intended for parsing "NAME=value"
23 * tokens. It will return the device matching the specified token, NULL if
24 * nothing is found, or copy of the string if it's not in "NAME=value"
25 * format.
26 * get_devname() takes the same parameters and works the same way as
27 * blkid_get_devname() except it can handle '=' in the file name.
28 */
get_devname(blkid_cache cache,const char * token,const char * value)29 char *get_devname(blkid_cache cache, const char *token, const char *value)
30 {
31 int is_file = 0;
32 char *ret = NULL;
33
34 if (!token)
35 goto out;
36
37 if (value) {
38 ret = blkid_get_devname(cache, token, value);
39 goto out;
40 }
41
42 if (access(token, F_OK) == 0)
43 is_file = 1;
44
45 ret = blkid_get_devname(cache, token, NULL);
46 if (ret) {
47 /*
48 * In case of collision prefer the result from
49 * blkid_get_devname() to avoid a file masking file system with
50 * existing tag.
51 */
52 if (is_file && (strcmp(ret, token) != 0)) {
53 fprintf(stderr,
54 _("Collision found: '%s' refers to both '%s' "
55 "and a file '%s'. Using '%s'!\n"),
56 token, ret, token, ret);
57 }
58 goto out;
59 }
60
61 if (is_file)
62 ret = strdup(token);
63 out:
64 return ret;
65 }
66