lib/blkid/cache.c

   1 /*
   2  * cache.c - allocation/initialization/free routines for cache
   3  *
   4  * Copyright (C) 2001 Andreas Dilger
   5  * Copyright (C) 2003 Theodore Ts'o
   6  *
   7  * %Begin-Header%
   8  * This file may be redistributed under the terms of the
   9  * GNU Lesser General Public License.
  10  * %End-Header%
  11  */
  12
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include "blkidP.h"
  16
  17 int blkid_debug_mask = 0;
  18
  19 int blkid_get_cache(blkid_cache *ret_cache, const char *filename)
  20 {
  21         blkid_cache cache;
  22
  23 #ifdef CONFIG_BLKID_DEBUG
  24         if (!(blkid_debug_mask & DEBUG_INIT)) {
  25                 char *dstr = getenv("BLKID_DEBUG");
  26
  27                 if (dstr)
  28                         blkid_debug_mask = strtoul(dstr, 0, 0);
  29                 blkid_debug_mask |= DEBUG_INIT;
  30         }
  31 #endif
  32
  33         DBG(DEBUG_CACHE, printf("creating blkid cache (using %s)\n",
  34                                 filename ? filename : "default cache"));
  35
  36         if (!(cache = (blkid_cache) calloc(1, sizeof(struct blkid_struct_cache))))
  37                 return -BLKID_ERR_MEM;
  38
  39         INIT_LIST_HEAD(&cache->bic_devs);
  40         INIT_LIST_HEAD(&cache->bic_tags);
  41
  42         if (filename && !strlen(filename))
  43                 filename = 0;
  44         if (!filename && (getuid() == geteuid()))
  45                 filename = getenv("BLKID_FILE");
  46         if (!filename)
  47                 filename = BLKID_CACHE_FILE;
  48         cache->bic_filename = blkid_strdup(filename);
  49
  50         blkid_read_cache(cache);
  51
  52         *ret_cache = cache;
  53         return 0;
  54 }
  55
  56 void blkid_put_cache(blkid_cache cache)
  57 {
  58         if (!cache)
  59                 return;
  60
  61         (void) blkid_flush_cache(cache);
  62
  63         DBG(DEBUG_CACHE, printf("freeing cache struct\n"));
  64
  65         /* DEB_DUMP_CACHE(cache); */
  66
  67         while (!list_empty(&cache->bic_devs)) {
  68                 blkid_dev dev = list_entry(cache->bic_devs.next,
  69                                            struct blkid_struct_dev,
  70                                             bid_devs);
  71                 blkid_free_dev(dev);
  72         }
  73
  74         while (!list_empty(&cache->bic_tags)) {
  75                 blkid_tag tag = list_entry(cache->bic_tags.next,
  76                                            struct blkid_struct_tag,
  77                                            bit_tags);
  78
  79                 while (!list_empty(&tag->bit_names)) {
  80                         blkid_tag bad = list_entry(tag->bit_names.next,
  81                                                    struct blkid_struct_tag,
  82                                                    bit_names);
  83
  84                         DBG(DEBUG_CACHE, printf("warning: unfreed tag %s=%s\n",
  85                                                 bad->bit_name, bad->bit_val));
  86                         blkid_free_tag(bad);
  87                 }
  88                 blkid_free_tag(tag);
  89         }
  90         if (cache->bic_filename)
  91                 free(cache->bic_filename);
  92
  93         free(cache);
  94 }
  95
  96 #ifdef TEST_PROGRAM
  97 int main(int argc, char** argv)
  98 {
  99         blkid_cache cache = NULL;
 100         int ret;
 101
 102         blkid_debug_mask = DEBUG_ALL;
 103         if ((argc > 2)) {
 104                 fprintf(stderr, "Usage: %s [filename] \n", argv[0]);
 105                 exit(1);
 106         }
 107
 108         if ((ret = blkid_get_cache(&cache, argv[1])) < 0) {
 109                 fprintf(stderr, "error %d parsing cache file %s\n", ret,
 110                         argv[1] ? argv[1] : BLKID_CACHE_FILE);
 111                 exit(1);
 112         }
 113         if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
 114                 fprintf(stderr, "%s: error creating cache (%d)\n",
 115                         argv[0], ret);
 116                 exit(1);
 117         }
 118         if ((ret = blkid_probe_all(cache) < 0))
 119                 fprintf(stderr, "error probing devices\n");
 120
 121         blkid_put_cache(cache);
 122
 123         return ret;
 124 }
 125 #endif