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 1.2 2007/06/17 07:36:28 dillon 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
  47 /*
  48  * Implement a Red-Black tree to cache the UUID table and perform lookups
  49  */
  50 struct uuid_rbnode {
  51         RB_ENTRY(uuid_rbnode) unode;
  52         RB_ENTRY(uuid_rbnode) nnode;
  53         struct uuid uuid;
  54         char *name;
  55 };
  56
  57 static void uuid_loadcache(const char *path);
  58
  59 static int uuid_name_loaded;
  60
  61 RB_HEAD(uuid_urbtree, uuid_rbnode);
  62 RB_STATIC_PROTOTYPE(uuid_urbtree, uuid_rbnode, unode, uuid_urbcmp);
  63 static struct uuid_urbtree uuid_urbroot = RB_INITIALIZER(uuid_urbroot);
  64
  65 RB_HEAD(uuid_nrbtree, uuid_rbnode);
  66 RB_STATIC_PROTOTYPE(uuid_nrbtree, uuid_rbnode, nnode, uuid_nrbcmp);
  67 static struct uuid_nrbtree uuid_nrbroot = RB_INITIALIZER(uuid_nrbroot);
  68
  69 static int
  70 uuid_urbcmp(struct uuid_rbnode *n1, struct uuid_rbnode *n2)
  71 {
  72         return(uuid_compare(&n1->uuid, &n2->uuid, NULL));
  73 }
  74
  75 static int
  76 uuid_nrbcmp(struct uuid_rbnode *n1, struct uuid_rbnode *n2)
  77 {
  78         return(strcasecmp(n1->name, n2->name));
  79 }
  80
  81 static int
  82 uuid_rbnamecmp(const char *name, struct uuid_rbnode *node)
  83 {
  84         return (strcasecmp(name, node->name));
  85 }
  86
  87 static int
  88 uuid_rbuuidcmp(const struct uuid *uuid, struct uuid_rbnode *node)
  89 {
  90         return(uuid_compare(uuid, &node->uuid, NULL));
  91 }
  92
  93 RB_STATIC_GENERATE(uuid_urbtree, uuid_rbnode, unode, uuid_urbcmp)
  94 RB_STATIC_GENERATE(uuid_nrbtree, uuid_rbnode, nnode, uuid_nrbcmp)
  95 RB_STATIC_GENERATE_XLOOKUP(uuid_urbtree, UUID, uuid_rbnode, unode,
  96                            uuid_rbuuidcmp, const struct uuid *)
  97 RB_STATIC_GENERATE_XLOOKUP(uuid_nrbtree, NAME, uuid_rbnode, nnode,
  98                            uuid_rbnamecmp, const char *)
  99
 100
 101 /*
 102  * Look up a UUID by its address.  Returns 0 on success or an error
 103  */
 104 void
 105 uuid_addr_lookup(const uuid_t *u, char **strp, uint32_t *status)
 106 {
 107         struct uuid_rbnode *node;
 108
 109         if (*strp) {
 110                 free(*strp);
 111                 *strp = NULL;
 112         }
 113         if (u) {
 114                 if (uuid_name_loaded == 0) {
 115                         uuid_loadcache("/etc/uuids");
 116                         uuid_loadcache("/etc/uuids.local");
 117                         uuid_name_loaded = 1;
 118                 }
 119                 node = uuid_urbtree_RB_LOOKUP_UUID(&uuid_urbroot, u);
 120                 if (node) {
 121                         *strp = strdup(node->name);
 122                         if (status)
 123                                 *status = uuid_s_ok;
 124                         return;
 125                 }
 126         }
 127         if (status)
 128                 *status = uuid_s_not_found;
 129 }
 130
 131 /*
 132  * Look up a UUID by its name.  Returns 0 on success or an error.
 133  */
 134 void
 135 uuid_name_lookup(uuid_t *u, const char *name, uint32_t *status)
 136 {
 137         struct uuid_rbnode *node;
 138
 139         if (name) {
 140                 if (uuid_name_loaded == 0) {
 141                         uuid_loadcache("/etc/uuids");
 142                         uuid_loadcache("/etc/uuids.local");
 143                         uuid_name_loaded = 1;
 144                 }
 145                 node = uuid_nrbtree_RB_LOOKUP_NAME(&uuid_nrbroot, name);
 146                 if (node) {
 147                         if (u)
 148                                 *u = node->uuid;
 149                         if (status)
 150                                 *status = uuid_s_ok;
 151                         return;
 152                 }
 153         }
 154         if (u)
 155                 bzero(u, sizeof(*u));
 156         if (status)
 157                 *status = uuid_s_not_found;
 158 }
 159
 160 /*
 161  * Clear out the lookup cache.  The next lookup will reload the database
 162  * or re-query or whatever.
 163  */
 164 static
 165 int
 166 uuid_freenode(struct uuid_rbnode *node, void *arg __unused)
 167 {
 168         uuid_urbtree_RB_REMOVE(&uuid_urbroot, node);
 169         uuid_nrbtree_RB_REMOVE(&uuid_nrbroot, node);
 170         free(node->name);
 171         free(node);
 172 }
 173
 174 void
 175 uuid_reset_lookup(void)
 176 {
 177         uuid_urbtree_RB_SCAN(&uuid_urbroot, NULL, uuid_freenode, NULL);
 178         uuid_name_loaded = 0;
 179 }
 180
 181 static
 182 void
 183 uuid_loadcache(const char *path)
 184 {
 185         struct uuid_rbnode *node;
 186         uint32_t status;
 187         FILE *fp;
 188         char *line;
 189         char *uuid;
 190         char *name;
 191         char *last;
 192         size_t len;
 193
 194         if ((fp = fopen(path, "r")) == NULL)
 195                 return;
 196         while ((line = fgetln(fp, &len)) != NULL) {
 197                 if (len == 0 || *line == '#')
 198                         continue;
 199                 line[len-1] = 0;
 200                 uuid = strtok_r(line, " \t\r", &last);
 201                 if (uuid == NULL)
 202                         continue;
 203                 name = strtok_r(NULL, "", &last);
 204                 name = strchr(name, '"');
 205                 if (name == NULL)
 206                         continue;
 207                 *name++ = 0;
 208                 if (strchr(name, '"') == NULL)
 209                         continue;
 210                 *strchr(name, '"') = 0;
 211                 node = malloc(sizeof(*node));
 212                 node->name = strdup(name);
 213                 uuid_from_string(uuid, &node->uuid, &status);
 214                 if (status == 0) {
 215                         if (uuid_urbtree_RB_FIND(&uuid_urbroot, node) ||
 216                             uuid_nrbtree_RB_FIND(&uuid_nrbroot, node))
 217                                 status = 1;
 218                 }
 219                 if (status == 0) {
 220                         uuid_urbtree_RB_INSERT(&uuid_urbroot, node);
 221                         uuid_nrbtree_RB_INSERT(&uuid_nrbroot, node);
 222                 } else {
 223                         free(node);
 224                         free(node->name);
 225                 }
 226         }
 227         fclose(fp);
 228 }
 229
 230