/**
* mnt_fs_match_source:
* @fs: filesystem
* @source: tag or path (device or so)
* @cache: tags/paths cache or NULL
*
* Possible are four attempts:
* 1) compare @source with @fs->source
* 2) compare realpath(@source) with @fs->source
* 3) compare realpath(@source) with realpath(@fs->source)
* 4) compare realpath(@source) with evaluated tag from @fs->source
*
* The 2nd, 3rd and 4th attempts are not performed when @cache is NULL. The
* 2nd and 3rd attempts are not performed if @fs->source is tag.
*
* Returns: 1 if @fs source is equal to @source else 0.
*/
int mnt_fs_match_source(mnt_fs *fs, const char *source, mnt_cache *cache)
{
char *cn;
const char *src, *t, *v;
if (!fs || !source || !fs->source)
return 0;
/* 1) native paths/tags */
if (!strcmp(source, fs->source))
return 1;
if (!cache)
return 0;
if (fs->flags & (MNT_FS_NET | MNT_FS_PSEUDO))
return 0;
cn = mnt_resolve_spec(source, cache);
if (!cn)
return 0;
/* 2) canonicalized and native */
src = mnt_fs_get_srcpath(fs);
if (src && !strcmp(cn, src))
return 1;
/* 3) canonicalized and canonicalized */
if (src) {
src = mnt_resolve_path(src, cache);
if (src && !strcmp(cn, src))
return 1;
}
if (src || mnt_fs_get_tag(fs, &t, &v))
/* src path does not match and tag is not defined */
return 0;
/* read @source's tags to the cache */
if (mnt_cache_read_tags(cache, cn) < 0) {
if (errno == EACCES) {
/* we don't have permissions to read TAGs from
* @source, but can translate @fs tag to devname.
*
* (because libblkid uses udev symlinks and this is
* accessible for non-root uses)
*/
char *x = mnt_resolve_tag(t, v, cache);
if (x && !strcmp(x, cn))
return 1;
}
return 0;
}
/* 4) has the @source a tag that matches with tag from @fs ? */
if (mnt_cache_device_has_tag(cache, cn, t, v))
return 1;
return 0;
}
/**
* mnt_cache_find_tag_value:
* @cache: cache for results
* @devname: device name
* @token: tag name ("LABEL" or "UUID")
*
* Returns: LABEL or UUID for the @devname or NULL in case of error.
*/
char *mnt_cache_find_tag_value(struct libmnt_cache *cache,
const char *devname, const char *token)
{
if (!cache || !devname || !token)
return NULL;
if (mnt_cache_read_tags(cache, devname) != 0)
return NULL;
return cache_find_tag_value(cache, devname, token);
}
int test_read_tags(struct libmnt_test *ts, int argc, char *argv[])
{
char line[BUFSIZ];
struct libmnt_cache *cache;
int i;
cache = mnt_new_cache();
if (!cache)
return -ENOMEM;
while(fgets(line, sizeof(line), stdin)) {
size_t sz = strlen(line);
if (line[sz - 1] == '\n')
line[sz - 1] = '\0';
if (!strcmp(line, "quit"))
break;
if (*line == '/') {
if (mnt_cache_read_tags(cache, line) < 0)
fprintf(stderr, "%s: read tags failed\n", line);
} else if (strchr(line, '=')) {
char *tag, *val;
const char *cn = NULL;
if (!blkid_parse_tag_string(line, &tag, &val)) {
cn = cache_find_tag(cache, tag, val);
free(tag);
free(val);
}
if (cn)
printf("%s: %s\n", line, cn);
else
printf("%s: not cached\n", line);
}
}
for (i = 0; i < cache->nents; i++) {
struct mnt_cache_entry *e = &cache->ents[i];
if (!(e->flag & MNT_CACHE_ISTAG))
continue;
printf("%15s : %5s : %s\n", e->value, e->key,
e->key + strlen(e->key) + 1);
}
mnt_free_cache(cache);
return 0;
}
static int __mnt_cache_find_tag_value(struct libmnt_cache *cache,
const char *devname, const char *token, char **data)
{
int rc = 0;
if (!cache || !devname || !token || !data)
return -EINVAL;
rc = mnt_cache_read_tags(cache, devname);
if (rc)
return rc;
*data = cache_find_tag_value(cache, devname, token);
return *data ? 0 : -1;
}
/**
* mnt_cache_find_tag_value:
* @cache: cache for results
* @devname: device name
* @token: tag name ("LABEL" or "UUID")
*
* Returns: LABEL or UUID for the @devname or NULL in case of error.
*/
char *mnt_cache_find_tag_value(struct libmnt_cache *cache,
const char *devname, const char *token)
{
int i;
if (!cache || !devname || !token)
return NULL;
if (mnt_cache_read_tags(cache, devname) != 0)
return NULL;
for (i = 0; i < cache->nents; i++) {
struct mnt_cache_entry *e = &cache->ents[i];
if (!(e->flag & MNT_CACHE_ISTAG))
continue;
if (strcmp(e->real, devname) == 0 && /* dev name */
strcmp(token, e->native) == 0) /* tag name */
return e->native + strlen(token) + 1; /* tag value */
}
return NULL;
}
