Changes to update Tomato RAF.

[tomato.git] / release / src / router / busybox / e2fsprogs / old_e2fsprogs / blkid / tag.c

/* vi: set sw=4 ts=4: */
/*
 * 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 <stdlib.h>
#include <string.h>
#include <stdio.h>

#include "blkidP.h"

static blkid_tag blkid_new_tag(void)
{
        blkid_tag tag;

        tag = xzalloc(sizeof(struct blkid_struct_tag));

        INIT_LIST_HEAD(&tag->bit_tags);
        INIT_LIST_HEAD(&tag->bit_names);

        return tag;
}

#ifdef CONFIG_BLKID_DEBUG
void blkid_debug_dump_tag(blkid_tag tag)
{
        if (!tag) {
                printf("    tag: NULL\n");
                return;
        }

        printf("    tag: %s=\"%s\"\n", tag->bit_name, tag->bit_val);
}
#endif

void blkid_free_tag(blkid_tag tag)
{
        if (!tag)
                return;

        DBG(DEBUG_TAG, printf("    freeing tag %s=%s\n", tag->bit_name,
                   tag->bit_val ? tag->bit_val : "(NULL)"));
        DBG(DEBUG_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;

        if (!dev || !type)
                return NULL;

        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;
}

/*
 * 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(DEBUG_TAG,
                            printf("    found cache tag head %s\n", 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 = NULL;

        if (!dev || !name)
                return -BLKID_ERR_PARAM;

        if (!(val = blkid_strndup(value, vlength)) && value)
                return -BLKID_ERR_MEM;
        t = blkid_find_tag_dev(dev, name);
        if (!value) {
                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 = blkid_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(DEBUG_TAG,
                                    printf("    creating new cache tag head %s\n", name));
                                head->bit_name = blkid_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 (!strcmp(name, "TYPE"))
                dev->bid_type = val;
        else if (!strcmp(name, "LABEL"))
                dev->bid_label = val;
        else if (!strcmp(name, "UUID"))
                dev->bid_uuid = val;

        if (dev->bid_cache)
                dev->bid_cache->bic_flags |= BLKID_BIC_FL_CHANGED;
        return 0;

errout:
        blkid_free_tag(t);
        if (!t)
                free(val);
        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(DEBUG_TAG, printf("trying to parse '%s' as a tag\n", token));

        if (!token || !(cp = strchr(token, '=')))
                return -1;

        name = blkid_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';
        }
        value = blkid_strdup(value);
        if (!value)
                goto errout;

        *ret_type = name;
        *ret_val = value;

        return 0;

errout:
        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;

        iter = xmalloc(sizeof(struct blkid_struct_tag_iterate));
        iter->magic = TAG_ITERATE_MAGIC;
        iter->dev = dev;
        iter->p = dev->bid_tags.next;
        return iter;
}

/*
 * Return 0 on success, -1 on error
 */
extern int blkid_tag_next(blkid_tag_iterate iter,
                          const char **type, const char **value)
{
        blkid_tag tag;

        *type = 0;
        *value = 0;
        if (!iter || iter->magic != TAG_ITERATE_MAGIC ||
            iter->p == &iter->dev->bid_tags)
                return -1;
        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.
 *
 * XXX there should also be an interface which uses an iterator so we
 * can get all of the devices which match a type/value search parameter.
 */
extern 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;

        if (!cache || !type || !value)
                return NULL;

        blkid_read_cache(cache);

        DBG(DEBUG_TAG, printf("looking for %s=%s in cache\n", 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) {
                                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->bid_flags & BLKID_BID_FL_VERIFIED))
                        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 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", prog);
        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':
                        blkid_debug_mask = strtoul (optarg, &tmp, 0);
                        if (*tmp) {
                                fprintf(stderr, "Invalid debug mask: %d\n",
                                        optarg);
                                exit(1);
                        }
                        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: cannot find device in blkid cache\n");
                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