lib/libc/uuid/uuid_name_lookup.c

   1 /*
   2  * Copyright (c) 2007 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/lib/libc/uuid/uuid_name_lookup.c,v 1.5 2007/11/25 01:28:23 swildner Exp $
  35  */
  36 /*
  37  * Implement UUID-to-NAME and NAME-to-UUID functions
  38  */
  39
  40 #include <sys/types.h>
  41 #include <sys/tree.h>
  42 #include <uuid.h>
  43 #include <errno.h>
  44 #include <string.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47
  48 /*
  49  * Implement a Red-Black tree to cache the UUID table and perform lookups
  50  */
  51 struct uuid_rbnode {
  52         RB_ENTRY(uuid_rbnode) unode;
  53         RB_ENTRY(uuid_rbnode) nnode;
  54         struct uuid uuid;
  55         char *name;
  56 };
  57
  58 static void uuid_loadcache(const char *path);
  59
  60 static int uuid_name_loaded;
  61
  62 RB_HEAD(uuid_urbtree, uuid_rbnode);
  63 RB_STATIC_PROTOTYPE(uuid_urbtree, uuid_rbnode, unode, uuid_urbcmp);
  64 static struct uuid_urbtree uuid_urbroot = RB_INITIALIZER(uuid_urbroot);
  65
  66 RB_HEAD(uuid_nrbtree, uuid_rbnode);
  67 RB_STATIC_PROTOTYPE(uuid_nrbtree, uuid_rbnode, nnode, uuid_nrbcmp);
  68 static struct uuid_nrbtree uuid_nrbroot = RB_INITIALIZER(uuid_nrbroot);
  69
  70 static int
  71 uuid_urbcmp(struct uuid_rbnode *n1, struct uuid_rbnode *n2)
  72 {
  73         return(uuid_compare(&n1->uuid, &n2->uuid, NULL));
  74 }
  75
  76 static int
  77 uuid_nrbcmp(struct uuid_rbnode *n1, struct uuid_rbnode *n2)
  78 {
  79         return(strcasecmp(n1->name, n2->name));
  80 }
  81
  82 static int
  83 uuid_rbnamecmp(const char *name, struct uuid_rbnode *node)
  84 {
  85         return (strcasecmp(name, node->name));
  86 }
  87
  88 static int
  89 uuid_rbuuidcmp(const struct uuid *uuid, struct uuid_rbnode *node)
  90 {
  91         return(uuid_compare(uuid, &node->uuid, NULL));
  92 }
  93
  94 RB_STATIC_GENERATE(uuid_urbtree, uuid_rbnode, unode, uuid_urbcmp)
  95 RB_STATIC_GENERATE(uuid_nrbtree, uuid_rbnode, nnode, uuid_nrbcmp)
  96 RB_STATIC_GENERATE_XLOOKUP(uuid_urbtree, UUID, uuid_rbnode, unode,
  97                            uuid_rbuuidcmp, const struct uuid *)
  98 RB_STATIC_GENERATE_XLOOKUP(uuid_nrbtree, NAME, uuid_rbnode, nnode,
  99                            uuid_rbnamecmp, const char *)
 100
 101
 102 /*
 103  * Look up a UUID by its address.  Returns 0 on success or an error
 104  */
 105 void
 106 uuid_addr_lookup(const uuid_t *u, char **strp, uint32_t *status)
 107 {
 108         struct uuid_rbnode *node;
 109
 110         if (*strp) {
 111                 free(*strp);
 112                 *strp = NULL;
 113         }
 114         if (u) {
 115                 if (uuid_name_loaded == 0) {
 116                         /*
 117                          * /etc/uuids will override /etc/defaults/uuids
 118                          */
 119                         uuid_loadcache("/etc/uuids");
 120                         uuid_loadcache("/etc/defaults/uuids");
 121                         uuid_name_loaded = 1;
 122                 }
 123                 node = uuid_urbtree_RB_LOOKUP_UUID(&uuid_urbroot, u);
 124                 if (node) {
 125                         *strp = strdup(node->name);
 126                         if (status)
 127                                 *status = uuid_s_ok;
 128                         return;
 129                 }
 130         }
 131         if (status)
 132                 *status = uuid_s_not_found;
 133 }
 134
 135 /*
 136  * Look up a UUID by its name.  Returns 0 on success or an error.
 137  */
 138 void
 139 uuid_name_lookup(uuid_t *u, const char *name, uint32_t *status)
 140 {
 141         struct uuid_rbnode *node;
 142
 143         if (name) {
 144                 if (uuid_name_loaded == 0) {
 145                         uuid_loadcache("/etc/uuids");
 146                         uuid_loadcache("/etc/defaults/uuids");
 147                         uuid_name_loaded = 1;
 148                 }
 149                 node = uuid_nrbtree_RB_LOOKUP_NAME(&uuid_nrbroot, name);
 150                 if (node) {
 151                         if (u)
 152                                 *u = node->uuid;
 153                         if (status)
 154                                 *status = uuid_s_ok;
 155                         return;
 156                 }
 157         }
 158         if (u)
 159                 bzero(u, sizeof(*u));
 160         if (status)
 161                 *status = uuid_s_not_found;
 162 }
 163
 164 /*
 165  * Clear out the lookup cache.  The next lookup will reload the database
 166  * or re-query or whatever.
 167  */
 168 static
 169 int
 170 uuid_freenode(struct uuid_rbnode *node, void *arg __unused)
 171 {
 172         uuid_urbtree_RB_REMOVE(&uuid_urbroot, node);
 173         uuid_nrbtree_RB_REMOVE(&uuid_nrbroot, node);
 174         free(node->name);
 175         free(node);
 176 }
 177
 178 void
 179 uuid_reset_lookup(void)
 180 {
 181         uuid_urbtree_RB_SCAN(&uuid_urbroot, NULL, uuid_freenode, NULL);
 182         uuid_name_loaded = 0;
 183 }
 184
 185 static
 186 void
 187 uuid_loadcache(const char *path)
 188 {
 189         struct uuid_rbnode *node;
 190         uint32_t status;
 191         FILE *fp;
 192         char *line;
 193         char *uuid;
 194         char *name;
 195         char *last;
 196         size_t len;
 197
 198         if ((fp = fopen(path, "r")) == NULL)
 199                 return;
 200         while ((line = fgetln(fp, &len)) != NULL) {
 201                 if (len == 0 || *line == '#')
 202                         continue;
 203                 line[len-1] = 0;
 204                 uuid = strtok_r(line, " \t\r", &last);
 205                 if (uuid == NULL)
 206                         continue;
 207                 name = strtok_r(NULL, "", &last);
 208                 name = strchr(name, '"');
 209                 if (name == NULL)
 210                         continue;
 211                 *name++ = 0;
 212                 if (strchr(name, '"') == NULL)
 213                         continue;
 214                 *strchr(name, '"') = 0;
 215                 node = malloc(sizeof(*node));
 216                 node->name = strdup(name);
 217                 uuid_from_string(uuid, &node->uuid, &status);
 218                 if (status == 0) {
 219                         if (uuid_urbtree_RB_FIND(&uuid_urbroot, node) ||
 220                             uuid_nrbtree_RB_FIND(&uuid_nrbroot, node))
 221                                 status = 1;
 222                 }
 223                 if (status == 0) {
 224                         uuid_urbtree_RB_INSERT(&uuid_urbroot, node);
 225                         uuid_nrbtree_RB_INSERT(&uuid_nrbroot, node);
 226                 } else {
 227                         free(node);
 228                         free(node->name);
 229                 }
 230         }
 231         fclose(fp);
 232 }
 233
 234