[821] | 1 | /*
|
---|
| 2 | * resolve.c - resolve names and tags into specific devices
|
---|
| 3 | *
|
---|
| 4 | * Copyright (C) 2001, 2003 Theodore Ts'o.
|
---|
| 5 | * Copyright (C) 2001 Andreas Dilger
|
---|
| 6 | *
|
---|
| 7 | * %Begin-Header%
|
---|
| 8 | * This file may be redistributed under the terms of the
|
---|
| 9 | * GNU Lesser General Public License.
|
---|
| 10 | * %End-Header%
|
---|
| 11 | */
|
---|
| 12 |
|
---|
| 13 | #include <stdio.h>
|
---|
| 14 | #if HAVE_UNISTD_H
|
---|
| 15 | #include <unistd.h>
|
---|
| 16 | #endif
|
---|
| 17 | #include <stdlib.h>
|
---|
| 18 | #include <fcntl.h>
|
---|
| 19 | #include <string.h>
|
---|
| 20 | #include <sys/types.h>
|
---|
| 21 | #include <sys/stat.h>
|
---|
| 22 | #include "blkidP.h"
|
---|
| 23 | #include "probe.h"
|
---|
| 24 |
|
---|
| 25 | /*
|
---|
| 26 | * Find a tagname (e.g. LABEL or UUID) on a specific device.
|
---|
| 27 | */
|
---|
| 28 | char *blkid_get_tag_value(blkid_cache cache, const char *tagname,
|
---|
| 29 | const char *devname)
|
---|
| 30 | {
|
---|
| 31 | blkid_tag found;
|
---|
| 32 | blkid_dev dev;
|
---|
| 33 | blkid_cache c = cache;
|
---|
| 34 | char *ret = NULL;
|
---|
| 35 |
|
---|
| 36 | DBG(DEBUG_RESOLVE, printf("looking for %s on %s\n", tagname, devname));
|
---|
| 37 |
|
---|
| 38 | if (!devname)
|
---|
| 39 | return NULL;
|
---|
| 40 |
|
---|
| 41 | if (!cache) {
|
---|
| 42 | if (blkid_get_cache(&c, NULL) < 0)
|
---|
| 43 | return NULL;
|
---|
| 44 | }
|
---|
| 45 |
|
---|
| 46 | if ((dev = blkid_get_dev(c, devname, BLKID_DEV_NORMAL)) &&
|
---|
| 47 | (found = blkid_find_tag_dev(dev, tagname)))
|
---|
| 48 | ret = blkid_strdup(found->bit_val);
|
---|
| 49 |
|
---|
| 50 | if (!cache)
|
---|
| 51 | blkid_put_cache(c);
|
---|
| 52 |
|
---|
| 53 | return ret;
|
---|
| 54 | }
|
---|
| 55 |
|
---|
| 56 | /*
|
---|
| 57 | * Locate a device name from a token (NAME=value string), or (name, value)
|
---|
| 58 | * pair. In the case of a token, value is ignored. If the "token" is not
|
---|
| 59 | * of the form "NAME=value" and there is no value given, then it is assumed
|
---|
| 60 | * to be the actual devname and a copy is returned.
|
---|
| 61 | */
|
---|
| 62 | char *blkid_get_devname(blkid_cache cache, const char *token,
|
---|
| 63 | const char *value)
|
---|
| 64 | {
|
---|
| 65 | blkid_dev dev;
|
---|
| 66 | blkid_cache c = cache;
|
---|
| 67 | char *t = 0, *v = 0;
|
---|
| 68 | char *ret = NULL;
|
---|
| 69 |
|
---|
| 70 | if (!token)
|
---|
| 71 | return NULL;
|
---|
| 72 |
|
---|
| 73 | if (!cache) {
|
---|
| 74 | if (blkid_get_cache(&c, NULL) < 0)
|
---|
| 75 | return NULL;
|
---|
| 76 | }
|
---|
| 77 |
|
---|
| 78 | DBG(DEBUG_RESOLVE,
|
---|
| 79 | printf("looking for %s%s%s %s\n", token, value ? "=" : "",
|
---|
| 80 | value ? value : "", cache ? "in cache" : "from disk"));
|
---|
| 81 |
|
---|
| 82 | if (!value) {
|
---|
| 83 | if (!strchr(token, '='))
|
---|
| 84 | return blkid_strdup(token);
|
---|
| 85 | blkid_parse_tag_string(token, &t, &v);
|
---|
| 86 | if (!t || !v)
|
---|
| 87 | goto errout;
|
---|
| 88 | token = t;
|
---|
| 89 | value = v;
|
---|
| 90 | }
|
---|
| 91 |
|
---|
| 92 | dev = blkid_find_dev_with_tag(c, token, value);
|
---|
| 93 | if (!dev)
|
---|
| 94 | goto errout;
|
---|
| 95 |
|
---|
| 96 | ret = blkid_strdup(blkid_dev_devname(dev));
|
---|
| 97 |
|
---|
| 98 | errout:
|
---|
| 99 | free(t);
|
---|
| 100 | free(v);
|
---|
| 101 | if (!cache) {
|
---|
| 102 | blkid_put_cache(c);
|
---|
| 103 | }
|
---|
| 104 | return (ret);
|
---|
| 105 | }
|
---|
| 106 |
|
---|
| 107 | #ifdef TEST_PROGRAM
|
---|
| 108 | int main(int argc, char **argv)
|
---|
| 109 | {
|
---|
| 110 | char *value;
|
---|
| 111 | blkid_cache cache;
|
---|
| 112 |
|
---|
| 113 | blkid_debug_mask = DEBUG_ALL;
|
---|
| 114 | if (argc != 2 && argc != 3) {
|
---|
| 115 | fprintf(stderr, "Usage:\t%s tagname=value\n"
|
---|
| 116 | "\t%s tagname devname\n"
|
---|
| 117 | "Find which device holds a given token or\n"
|
---|
| 118 | "Find what the value of a tag is in a device\n",
|
---|
| 119 | argv[0], argv[0]);
|
---|
| 120 | exit(1);
|
---|
| 121 | }
|
---|
| 122 | if (blkid_get_cache(&cache, bb_dev_null) < 0) {
|
---|
| 123 | fprintf(stderr, "Couldn't get blkid cache\n");
|
---|
| 124 | exit(1);
|
---|
| 125 | }
|
---|
| 126 |
|
---|
| 127 | if (argv[2]) {
|
---|
| 128 | value = blkid_get_tag_value(cache, argv[1], argv[2]);
|
---|
| 129 | printf("%s has tag %s=%s\n", argv[2], argv[1],
|
---|
| 130 | value ? value : "<missing>");
|
---|
| 131 | } else {
|
---|
| 132 | value = blkid_get_devname(cache, argv[1], NULL);
|
---|
| 133 | printf("%s has tag %s\n", value ? value : "<none>", argv[1]);
|
---|
| 134 | }
|
---|
| 135 | blkid_put_cache(cache);
|
---|
| 136 | return value ? 0 : 1;
|
---|
| 137 | }
|
---|
| 138 | #endif
|
---|