e2fsprogs/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 <unistd.h>
  16 #include "blkidP.h"
  17
  18 int blkid_debug_mask = 0;
  19
  20 int blkid_get_cache(blkid_cache *ret_cache, const char *filename)
  21 {
  22         blkid_cache cache;
  23
  24 #ifdef CONFIG_BLKID_DEBUG
  25         if (!(blkid_debug_mask & DEBUG_INIT)) {
  26                 char *dstr = getenv("BLKID_DEBUG");
  27
  28                 if (dstr)
  29                         blkid_debug_mask = strtoul(dstr, 0, 0);
  30                 blkid_debug_mask |= DEBUG_INIT;
  31         }
  32 #endif
  33
  34         DBG(DEBUG_CACHE, printf("creating blkid cache (using %s)\n",
  35                                 filename ? filename : "default cache"));
  36
  37         if (!(cache = (blkid_cache) calloc(1, sizeof(struct blkid_struct_cache))))
  38                 return -BLKID_ERR_MEM;
  39
  40         INIT_LIST_HEAD(&cache->bic_devs);
  41         INIT_LIST_HEAD(&cache->bic_tags);
  42
  43         if (filename && !strlen(filename))
  44                 filename = 0;
  45         if (!filename && (getuid() == geteuid()))
  46                 filename = getenv("BLKID_FILE");
  47         if (!filename)
  48                 filename = BLKID_CACHE_FILE;
  49         cache->bic_filename = blkid_strdup(filename);
  50
  51         blkid_read_cache(cache);
  52
  53         *ret_cache = cache;
  54         return 0;
  55 }
  56
  57 void blkid_put_cache(blkid_cache cache)
  58 {
  59         if (!cache)
  60                 return;
  61
  62         (void) blkid_flush_cache(cache);
  63
  64         DBG(DEBUG_CACHE, printf("freeing cache struct\n"));
  65
  66         /* DEB_DUMP_CACHE(cache); */
  67
  68         while (!list_empty(&cache->bic_devs)) {
  69                 blkid_dev dev = list_entry(cache->bic_devs.next,
  70                                            struct blkid_struct_dev,
  71                                             bid_devs);
  72                 blkid_free_dev(dev);
  73         }
  74
  75         while (!list_empty(&cache->bic_tags)) {
  76                 blkid_tag tag = list_entry(cache->bic_tags.next,
  77                                            struct blkid_struct_tag,
  78                                            bit_tags);
  79
  80                 while (!list_empty(&tag->bit_names)) {
  81                         blkid_tag bad = list_entry(tag->bit_names.next,
  82                                                    struct blkid_struct_tag,
  83                                                    bit_names);
  84
  85                         DBG(DEBUG_CACHE, printf("warning: unfreed tag %s=%s\n",
  86                                                 bad->bit_name, bad->bit_val));
  87                         blkid_free_tag(bad);
  88                 }
  89                 blkid_free_tag(tag);
  90         }
  91         if (cache->bic_filename)
  92                 free(cache->bic_filename);
  93
  94         free(cache);
  95 }
  96
  97 #ifdef TEST_PROGRAM
  98 int main(int argc, char** argv)
  99 {
 100         blkid_cache cache = NULL;
 101         int ret;
 102
 103         blkid_debug_mask = DEBUG_ALL;
 104         if ((argc > 2)) {
 105                 fprintf(stderr, "Usage: %s [filename] \n", argv[0]);
 106                 exit(1);
 107         }
 108
 109         if ((ret = blkid_get_cache(&cache, argv[1])) < 0) {
 110                 fprintf(stderr, "error %d parsing cache file %s\n", ret,
 111                         argv[1] ? argv[1] : BLKID_CACHE_FILE);
 112                 exit(1);
 113         }
 114         if ((ret = blkid_get_cache(&cache, bb_dev_null)) != 0) {
 115                 fprintf(stderr, "%s: error creating cache (%d)\n",
 116                         argv[0], ret);
 117                 exit(1);
 118         }
 119         if ((ret = blkid_probe_all(cache) < 0))
 120                 fprintf(stderr, "error probing devices\n");
 121
 122         blkid_put_cache(cache);
 123
 124         return ret;
 125 }
 126 #endif