mirror of https://github.com/vitalif/e2fsprogs
131 lines
3.0 KiB
C
131 lines
3.0 KiB
C
/*
|
|
* resolve.c - resolve names and tags into specific devices
|
|
*
|
|
* Copyright (C) 2001 Theodore Ts'o.
|
|
* Copyright (C) 2001 Andreas Dilger
|
|
*
|
|
* %Begin-Header%
|
|
* This file may be redistributed under the terms of the
|
|
* GNU Lesser General Public License.
|
|
* %End-Header%
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#if HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
#include <fcntl.h>
|
|
#include <string.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include "blkid/blkid.h"
|
|
#include "probe.h"
|
|
|
|
#ifdef DEBUG_RESOLVE
|
|
#define DEB_RESOLVE(fmt, arg...) printf("resolve: " fmt, ## arg)
|
|
#else
|
|
#define DEB_RESOLVE(fmt, arg...) do {} while (0)
|
|
#endif
|
|
|
|
|
|
/*
|
|
* Find a tagname (e.g. LABEL or UUID) on a specific device.
|
|
*/
|
|
char *blkid_get_tagname_devname(blkid_cache *cache, const char *tagname,
|
|
const char *devname)
|
|
{
|
|
blkid_tag *tag, *found;
|
|
blkid_dev *dev;
|
|
char *ret = NULL;
|
|
|
|
DEB_RESOLVE("looking for %s on %s\n", tagname, devname);
|
|
|
|
if (!devname)
|
|
return NULL;
|
|
|
|
if (blkid_create_tag(NULL, &tag, tagname, NULL, 0) < 0)
|
|
return NULL;
|
|
|
|
if (!cache)
|
|
DEB_RESOLVE("no cache given, direct device probe\n");
|
|
|
|
if ((dev = blkid_get_devname(cache, devname)) &&
|
|
(found = blkid_find_tag_dev(dev, tag)))
|
|
ret = string_copy(found->bit_val);
|
|
|
|
if (!cache)
|
|
blkid_free_dev(dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Locate a device name from a token (NAME=value string), or (name, value)
|
|
* pair. In the case of a token, value is ignored. If the "token" is not
|
|
* of the form "NAME=value" and there is no value given, then it is assumed
|
|
* to be the actual devname and a copy is returned.
|
|
*
|
|
* The string returned must be freed with string_free().
|
|
*/
|
|
char *blkid_get_token(blkid_cache *cache, const char *token,
|
|
const char *value)
|
|
{
|
|
blkid_tag *tag = NULL, *found = NULL;
|
|
blkid_cache *c = cache;
|
|
char *name = NULL;
|
|
|
|
DEB_RESOLVE("looking for %s%c%s %s\n", token, value ? '=' : ' ',
|
|
value ? value : "", cache ? "in cache" : "from disk");
|
|
|
|
if (!(tag = blkid_token_to_tag(token))) {
|
|
if (!value)
|
|
return string_copy(token);
|
|
if (blkid_create_tag(NULL,&tag,token,value,strlen(value)) < 0)
|
|
return NULL;
|
|
}
|
|
|
|
if (!cache) {
|
|
if (blkid_read_cache(&c, NULL) < 0)
|
|
c = blkid_new_cache();
|
|
if (!c)
|
|
return NULL;
|
|
}
|
|
|
|
if ((found = blkid_get_tag_cache(c, tag)) && found->bit_dev)
|
|
name = string_copy(found->bit_dev->bid_name);
|
|
|
|
if (!cache) {
|
|
blkid_save_cache(c, NULL);
|
|
blkid_free_cache(c);
|
|
}
|
|
|
|
|
|
blkid_free_tag(tag);
|
|
return name;
|
|
}
|
|
|
|
#ifdef TEST_PROGRAM
|
|
int main(int argc, char **argv)
|
|
{
|
|
char *value;
|
|
|
|
if (argc != 2 && argc != 3) {
|
|
fprintf(stderr, "Usage:\t%s tagname=value\n"
|
|
"\t%s tagname devname\n"
|
|
"Find which device holds a given token or\n"
|
|
"Find what the value of a tag is in a device\n",
|
|
argv[0], argv[0]);
|
|
exit(1);
|
|
}
|
|
if (argv[2]) {
|
|
value = blkid_get_tagname_devname(NULL, argv[1], argv[2]);
|
|
printf("%s has tag %s=%s\n", argv[2], argv[1],
|
|
value ? value : "<missing>");
|
|
} else {
|
|
value = blkid_get_token(NULL, argv[1], NULL);
|
|
printf("%s has tag %s\n", value ? value : "<none>", argv[1]);
|
|
}
|
|
return value ? 0 : 1;
|
|
}
|
|
#endif
|