source: MondoRescue/branches/stable/mindi-busybox/e2fsprogs/blkid/dev.c@ 821

/*
 * dev.c - allocation/initialization/free routines for dev
 *
 * 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 "blkidP.h"

blkid_dev blkid_new_dev(void)
{
    blkid_dev dev;

    if (!(dev = (blkid_dev) calloc(1, sizeof(struct blkid_struct_dev))))
        return NULL;

    INIT_LIST_HEAD(&dev->bid_devs);
    INIT_LIST_HEAD(&dev->bid_tags);

    return dev;
}

void blkid_free_dev(blkid_dev dev)
{
    if (!dev)
        return;

    DBG(DEBUG_DEV,
        printf("  freeing dev %s (%s)\n", dev->bid_name, dev->bid_type));
    DBG(DEBUG_DEV, blkid_debug_dump_dev(dev));

    list_del(&dev->bid_devs);
    while (!list_empty(&dev->bid_tags)) {
        blkid_tag tag = list_entry(dev->bid_tags.next,
                       struct blkid_struct_tag,
                       bit_tags);
        blkid_free_tag(tag);
    }
    if (dev->bid_name)
        free(dev->bid_name);
    free(dev);
}

/*
 * Given a blkid device, return its name
 */
const char *blkid_dev_devname(blkid_dev dev)
{
    return dev->bid_name;
}

#ifdef CONFIG_BLKID_DEBUG
void blkid_debug_dump_dev(blkid_dev dev)
{
    struct list_head *p;

    if (!dev) {
        printf("  dev: NULL\n");
        return;
    }

    printf("  dev: name = %s\n", dev->bid_name);
    printf("  dev: DEVNO=\"0x%0llx\"\n", dev->bid_devno);
    printf("  dev: TIME=\"%lu\"\n", dev->bid_time);
    printf("  dev: PRI=\"%d\"\n", dev->bid_pri);
    printf("  dev: flags = 0x%08X\n", dev->bid_flags);

    list_for_each(p, &dev->bid_tags) {
        blkid_tag tag = list_entry(p, struct blkid_struct_tag, bit_tags);
        if (tag)   
            printf("    tag: %s=\"%s\"\n", tag->bit_name, 
                   tag->bit_val);
        else
            printf("    tag: NULL\n");
    }
    printf("\n");
}
#endif

/*
 * dev 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 devices in a blkid cache
 */
#define DEV_ITERATE_MAGIC   0x01a5284c

struct blkid_struct_dev_iterate {
    int         magic;
    blkid_cache     cache;
    struct list_head    *p;
};

blkid_dev_iterate blkid_dev_iterate_begin(blkid_cache cache)
{
    blkid_dev_iterate   iter;

    iter = xmalloc(sizeof(struct blkid_struct_dev_iterate));
    iter->magic = DEV_ITERATE_MAGIC;
    iter->cache = cache;
    iter->p = cache->bic_devs.next;
    return (iter);
}

/*
 * Return 0 on success, -1 on error
 */
extern int blkid_dev_next(blkid_dev_iterate iter,
              blkid_dev *dev)
{
    *dev = 0;
    if (!iter || iter->magic != DEV_ITERATE_MAGIC ||
        iter->p == &iter->cache->bic_devs)
        return -1;
    *dev = list_entry(iter->p, struct blkid_struct_dev, bid_devs);
    iter->p = iter->p->next;
    return 0;
}

void blkid_dev_iterate_end(blkid_dev_iterate iter)
{
    if (!iter || iter->magic != DEV_ITERATE_MAGIC)
        return;
    iter->magic = 0;
    free(iter);
}

#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]\n", prog);
    fprintf(stderr, "\tList all devices and exit\n", prog);
    exit(1);
}

int main(int argc, char **argv)
{
    blkid_dev_iterate   iter;
    blkid_cache         cache = NULL;
    blkid_dev       dev;
    int         c, ret;
    char            *tmp;
    char            *file = NULL;
    char            *search_type = NULL;
    char            *search_value = NULL;

    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+2) {
        search_type = argv[optind];
        search_value = argv[optind+1];
        optind += 2;
    }
    if (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);
    }

    iter = blkid_dev_iterate_begin(cache);
    if (search_type)
        blkid_dev_set_search(iter, search_type, search_value);
    while (blkid_dev_next(iter, &dev) == 0) {
        printf("Device: %s\n", blkid_dev_devname(dev));
    }
    blkid_dev_iterate_end(iter);


    blkid_put_cache(cache);
    return (0);
}
#endif