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Diffstat (limited to 'libblkid/src/dev.c')
-rw-r--r-- | libblkid/src/dev.c | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/libblkid/src/dev.c b/libblkid/src/dev.c new file mode 100644 index 0000000..056df2b --- /dev/null +++ b/libblkid/src/dev.c @@ -0,0 +1,279 @@ +/* + * 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" + +/* + * NOTE: reference manual is not structured as code. The following section is a generic + * section for all high-level cache search+iterate routines. + */ + +/** + * SECTION:search + * @title: Search and iterate + * @short_description: search devices and iterate over devices in the cache. + * + * Note that high-level probing API provides information about superblocks + * (filesystems/raids) only. For partitions and topology is necessary to use + * the low-level API. + */ + +blkid_dev blkid_new_dev(void) +{ + blkid_dev dev; + + if (!(dev = calloc(1, sizeof(struct blkid_struct_dev)))) + return NULL; + + DBG(DEV, ul_debugobj(dev, "alloc")); + 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(DEV, ul_debugobj(dev, "freeing (%s)", dev->bid_name)); + + 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); + } + free(dev->bid_xname); + free(dev->bid_name); + free(dev); +} + +/* + * Given a blkid device, return its name. The function returns the name + * previously used for blkid_get_dev(). This name does not have to be canonical + * (real path) name, but for example symlink. + */ +const char *blkid_dev_devname(blkid_dev dev) +{ + if (!dev) + return NULL; + if (dev->bid_xname) + return dev->bid_xname; + return dev->bid_name; +} + +void blkid_debug_dump_dev(blkid_dev dev) +{ + struct list_head *p; + + if (!dev) { + printf(" dev: NULL\n"); + return; + } + + fprintf(stderr, " dev: name = %s\n", dev->bid_name); + fprintf(stderr, " dev: DEVNO=\"0x%0llx\"\n", (long long)dev->bid_devno); + fprintf(stderr, " dev: TIME=\"%ld.%ld\"\n", (long)dev->bid_time, (long)dev->bid_utime); + fprintf(stderr, " dev: PRI=\"%d\"\n", dev->bid_pri); + fprintf(stderr, " 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) + fprintf(stderr, " tag: %s=\"%s\"\n", tag->bit_name, + tag->bit_val); + else + fprintf(stderr, " tag: NULL\n"); + } +} + +/* + * 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 implementation. 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 trade-off 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; + char *search_type; + char *search_value; + struct list_head *p; +}; + +blkid_dev_iterate blkid_dev_iterate_begin(blkid_cache cache) +{ + blkid_dev_iterate iter; + + if (!cache) { + errno = EINVAL; + return NULL; + } + + iter = malloc(sizeof(struct blkid_struct_dev_iterate)); + if (iter) { + iter->magic = DEV_ITERATE_MAGIC; + iter->cache = cache; + iter->p = cache->bic_devs.next; + iter->search_type = NULL; + iter->search_value = NULL; + } + return iter; +} + +int blkid_dev_set_search(blkid_dev_iterate iter, + const char *search_type, const char *search_value) +{ + char *new_type, *new_value; + + if (!iter || iter->magic != DEV_ITERATE_MAGIC || !search_type || + !search_value) + return -1; + new_type = malloc(strlen(search_type)+1); + new_value = malloc(strlen(search_value)+1); + if (!new_type || !new_value) { + free(new_type); + free(new_value); + return -1; + } + strcpy(new_type, search_type); + strcpy(new_value, search_value); + free(iter->search_type); + free(iter->search_value); + iter->search_type = new_type; + iter->search_value = new_value; + return 0; +} + +/* + * Return 0 on success, -1 on error + */ +int blkid_dev_next(blkid_dev_iterate iter, + blkid_dev *ret_dev) +{ + blkid_dev dev; + + if (!ret_dev || !iter || iter->magic != DEV_ITERATE_MAGIC) + return -1; + *ret_dev = NULL; + while (iter->p != &iter->cache->bic_devs) { + dev = list_entry(iter->p, struct blkid_struct_dev, bid_devs); + iter->p = iter->p->next; + if (iter->search_type && + !blkid_dev_has_tag(dev, iter->search_type, + iter->search_value)) + continue; + *ret_dev = dev; + return 0; + } + return -1; +} + +void blkid_dev_iterate_end(blkid_dev_iterate iter) +{ + if (!iter || iter->magic != DEV_ITERATE_MAGIC) + return; + iter->magic = 0; + free(iter->search_type); + free(iter->search_value); + free(iter); +} + +#ifdef TEST_PROGRAM +#ifdef HAVE_GETOPT_H +#include <getopt.h> +#else +extern char *optarg; +extern int optind; +#endif + +static void __attribute__((__noreturn__)) usage(char *prog) +{ + fprintf(stderr, "Usage: %s [-f blkid_file] [-m debug_mask]\n", prog); + fprintf(stderr, "\tList all devices and exit\n"); + 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': + { + 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+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 |