/*
* tag.c - allocation/initialization/free routines for tag structs
*
* Copyright (C) 2001 Andreas Dilger
* Copyright (C) 2003 Theodore Ts'o
*
* %Begin-Header%
* This file may be redistributed under the terms of the
* GNU Lesser General Public License.
* %End-Header%
*/
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "blkidP.h"
static blkid_tag blkid_new_tag(void)
{
blkid_tag tag;
if (!(tag = (blkid_tag) calloc(1, sizeof(struct blkid_struct_tag))))
return NULL;
INIT_LIST_HEAD(&tag->bit_tags);
INIT_LIST_HEAD(&tag->bit_names);
return tag;
}
void blkid_debug_dump_tag(blkid_tag tag)
{
if (!tag) {
fprintf(stderr, " tag: NULL\n");
return;
}
fprintf(stderr, " tag: %s=\"%s\"\n", tag->bit_name, tag->bit_val);
}
void blkid_free_tag(blkid_tag tag)
{
if (!tag)
return;
DBG(TAG, ul_debug(" freeing tag %s=%s", tag->bit_name,
tag->bit_val ? tag->bit_val : "(NULL)"));
DBG(TAG, blkid_debug_dump_tag(tag));
list_del(&tag->bit_tags); /* list of tags for this device */
list_del(&tag->bit_names); /* list of tags with this type */
free(tag->bit_name);
free(tag->bit_val);
free(tag);
}
/*
* Find the desired tag on a device. If value is NULL, then the
* first such tag is returned, otherwise return only exact tag if found.
*/
blkid_tag blkid_find_tag_dev(blkid_dev dev, const char *type)
{
struct list_head *p;
list_for_each(p, &dev->bid_tags) {
blkid_tag tmp = list_entry(p, struct blkid_struct_tag,
bit_tags);
if (!strcmp(tmp->bit_name, type))
return tmp;
}
return NULL;
}
int blkid_dev_has_tag(blkid_dev dev, const char *type,
const char *value)
{
blkid_tag tag;
tag = blkid_find_tag_dev(dev, type);
if (!value)
return (tag != NULL);
if (!tag || strcmp(tag->bit_val, value))
return 0;
return 1;
}
/*
* Find the desired tag type in the cache.
* We return the head tag for this tag type.
*/
static blkid_tag blkid_find_head_cache(blkid_cache cache, const char *type)
{
blkid_tag head = NULL, tmp;
struct list_head *p;
if (!cache || !type)
return NULL;
list_for_each(p, &cache->bic_tags) {
tmp = list_entry(p, struct blkid_struct_tag, bit_tags);
if (!strcmp(tmp->bit_name, type)) {
DBG(TAG, ul_debug(" found cache tag head %s", type));
head = tmp;
break;
}
}
return head;
}
/*
* Set a tag on an existing device.
*
* If value is NULL, then delete the tagsfrom the device.
*/
int blkid_set_tag(blkid_dev dev, const char *name,
const char *value, const int vlength)
{
blkid_tag t = 0, head = 0;
char *val = 0;
char **dev_var = 0;
if (value && !(val = strndup(value, vlength)))
return -BLKID_ERR_MEM;
/*
* Certain common tags are linked directly to the device struct
* We need to know what they are before we do anything else because
* the function name parameter might get freed later on.
*/
if (!strcmp(name, "TYPE"))
dev_var = &dev->bid_type;
else if (!strcmp(name, "LABEL"))
dev_var = &dev->bid_label;
else if (!strcmp(name, "UUID"))
dev_var = &dev->bid_uuid;
t = blkid_find_tag_dev(dev, name);
if (!value) {
if (t)
blkid_free_tag(t);
} else if (t) {
if (!strcmp(t->bit_val, val)) {
/* Same thing, exit */
free(val);
return 0;
}
free(t->bit_val);
t->bit_val = val;
} else {
/* Existing tag not present, add to device */
if (!(t = blkid_new_tag()))
goto errout;
t->bit_name = strdup(name);
t->bit_val = val;
t->bit_dev = dev;
list_add_tail(&t->bit_tags, &dev->bid_tags);
if (dev->bid_cache) {
head = blkid_find_head_cache(dev->bid_cache,
t->bit_name);
if (!head) {
head = blkid_new_tag();
if (!head)
goto errout;
DBG(TAG, ul_debug(" creating new cache tag head %s", name));
head->bit_name = strdup(name);
if (!head->bit_name)
goto errout;
list_add_tail(&head->bit_tags,
&dev->bid_cache->bic_tags);
}
list_add_tail(&t->bit_names, &head->bit_names);
}
}
/* Link common tags directly to the device struct */
if (dev_var)
*dev_var = val;
if (dev->bid_cache)
dev->bid_cache->bic_flags |= BLKID_BIC_FL_CHANGED;
return 0;
errout:
if (t)
blkid_free_tag(t);
else
free(val);
if (head)
blkid_free_tag(head);
return -BLKID_ERR_MEM;
}
/*
* Parse a "NAME=value" string. This is slightly different than
* parse_token, because that will end an unquoted value at a space, while
* this will assume that an unquoted value is the rest of the token (e.g.
* if we are passed an already quoted string from the command-line we don't
* have to both quote and escape quote so that the quotes make it to
* us).
*
* Returns 0 on success, and -1 on failure.
*/
int blkid_parse_tag_string(const char *token, char **ret_type, char **ret_val)
{
char *name, *value, *cp;
DBG(TAG, ul_debug("trying to parse '%s' as a tag", token));
if (!token || !(cp = strchr(token, '=')))
return -1;
name = strdup(token);
if (!name)
return -1;
value = name + (cp - token);
*value++ = '\0';
if (*value == '"' || *value == '\'') {
char c = *value++;
if (!(cp = strrchr(value, c)))
goto errout; /* missing closing quote */
*cp = '\0';
}
if (ret_val) {
value = value && *value ? strdup(value) : NULL;
if (!value)
goto errout;
*ret_val = value;
}
if (ret_type)
*ret_type = name;
else
free(name);
return 0;
errout:
DBG(TAG, ul_debug("parse error: '%s'", token));
free(name);
return -1;
}
/*
* Tag iteration routines for the public libblkid interface.
*
* These routines do not expose the list.h implementation, which are a
* contamination of the namespace, and which force us to reveal far, far
* too much of our internal implemenation. I'm not convinced I want
* to keep list.h in the long term, anyway. It's fine for kernel
* programming, but performance is not the #1 priority for this
* library, and I really don't like the tradeoff of type-safety for
* performance for this application. [tytso:20030125.2007EST]
*/
/*
* This series of functions iterate over all tags in a device
*/
#define TAG_ITERATE_MAGIC 0x01a5284c
struct blkid_struct_tag_iterate {
int magic;
blkid_dev dev;
struct list_head *p;
};
blkid_tag_iterate blkid_tag_iterate_begin(blkid_dev dev)
{
blkid_tag_iterate iter;
if (!dev) {
errno = EINVAL;
return NULL;
}
iter = malloc(sizeof(struct blkid_struct_tag_iterate));
if (iter) {
iter->magic = TAG_ITERATE_MAGIC;
iter->dev = dev;
iter->p = dev->bid_tags.next;
}
return (iter);
}
/*
* Return 0 on success, -1 on error
*/
int blkid_tag_next(blkid_tag_iterate iter,
const char **type, const char **value)
{
blkid_tag tag;
if (!type || !value ||
!iter || iter->magic != TAG_ITERATE_MAGIC ||
iter->p == &iter->dev->bid_tags)
return -1;
*type = 0;
*value = 0;
tag = list_entry(iter->p, struct blkid_struct_tag, bit_tags);
*type = tag->bit_name;
*value = tag->bit_val;
iter->p = iter->p->next;
return 0;
}
void blkid_tag_iterate_end(blkid_tag_iterate iter)
{
if (!iter || iter->magic != TAG_ITERATE_MAGIC)
return;
iter->magic = 0;
free(iter);
}
/*
* This function returns a device which matches a particular
* type/value pair. If there is more than one device that matches the
* search specification, it returns the one with the highest priority
* value. This allows us to give preference to EVMS or LVM devices.
*/
blkid_dev blkid_find_dev_with_tag(blkid_cache cache,
const char *type,
const char *value)
{
blkid_tag head;
blkid_dev dev;
int pri;
struct list_head *p;
int probe_new = 0;
if (!cache || !type || !value)
return NULL;
blkid_read_cache(cache);
DBG(TAG, ul_debug("looking for %s=%s in cache", type, value));
try_again:
pri = -1;
dev = 0;
head = blkid_find_head_cache(cache, type);
if (head) {
list_for_each(p, &head->bit_names) {
blkid_tag tmp = list_entry(p, struct blkid_struct_tag,
bit_names);
if (!strcmp(tmp->bit_val, value) &&
(tmp->bit_dev->bid_pri > pri) &&
!access(tmp->bit_dev->bid_name, F_OK)) {
dev = tmp->bit_dev;
pri = dev->bid_pri;
}
}
}
if (dev && !(dev->bid_flags & BLKID_BID_FL_VERIFIED)) {
dev = blkid_verify(cache, dev);
if (!dev || (dev && (dev->bid_flags & BLKID_BID_FL_VERIFIED)))
goto try_again;
}
if (!dev && !probe_new) {
if (blkid_probe_all_new(cache) < 0)
return NULL;
probe_new++;
goto try_again;
}
if (!dev && !(cache->bic_flags & BLKID_BIC_FL_PROBED)) {
if (blkid_probe_all(cache) < 0)
return NULL;
goto try_again;
}
return dev;
}
#ifdef TEST_PROGRAM
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#else
extern char *optarg;
extern int optind;
#endif
void __attribute__((__noreturn__)) usage(char *prog)
{
fprintf(stderr, "Usage: %s [-f blkid_file] [-m debug_mask] device "
"[type value]\n",
prog);
fprintf(stderr, "\tList all tags for a device and exit\n");
exit(1);
}
int main(int argc, char **argv)
{
blkid_tag_iterate iter;
blkid_cache cache = NULL;
blkid_dev dev;
int c, ret, found;
int flags = BLKID_DEV_FIND;
char *tmp;
char *file = NULL;
char *devname = NULL;
char *search_type = NULL;
char *search_value = NULL;
const char *type, *value;
while ((c = getopt (argc, argv, "m:f:")) != EOF)
switch (c) {
case 'f':
file = optarg;
break;
case 'm':
{
int mask = strtoul (optarg, &tmp, 0);
if (*tmp) {
fprintf(stderr, "Invalid debug mask: %s\n",
optarg);
exit(1);
}
blkid_init_debug(mask);
break;
}
case '?':
usage(argv[0]);
}
if (argc > optind)
devname = argv[optind++];
if (argc > optind)
search_type = argv[optind++];
if (argc > optind)
search_value = argv[optind++];
if (!devname || (argc != optind))
usage(argv[0]);
if ((ret = blkid_get_cache(&cache, file)) != 0) {
fprintf(stderr, "%s: error creating cache (%d)\n",
argv[0], ret);
exit(1);
}
dev = blkid_get_dev(cache, devname, flags);
if (!dev) {
fprintf(stderr, "%s: Can not find device in blkid cache\n",
devname);
exit(1);
}
if (search_type) {
found = blkid_dev_has_tag(dev, search_type, search_value);
printf("Device %s: (%s, %s) %s\n", blkid_dev_devname(dev),
search_type, search_value ? search_value : "NULL",
found ? "FOUND" : "NOT FOUND");
return(!found);
}
printf("Device %s...\n", blkid_dev_devname(dev));
iter = blkid_tag_iterate_begin(dev);
while (blkid_tag_next(iter, &type, &value) == 0) {
printf("\tTag %s has value %s\n", type, value);
}
blkid_tag_iterate_end(iter);
blkid_put_cache(cache);
return (0);
}
#endif
