vswitchd/xenserver.c

   1 /* Copyright (c) 2009, 2010 Nicira, Inc.
   2  *
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 #include <config.h>
  17 #include "xenserver.h"
  18 #include <ctype.h>
  19 #include <errno.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <unistd.h>
  23 #include "dynamic-string.h"
  24 #include "process.h"
  25 #include "vlog.h"
  26
  27 VLOG_DEFINE_THIS_MODULE(xenserver);
  28
  29 static char *
  30 read_host_uuid(void)
  31 {
  32     static const char filename[] = "/etc/xensource-inventory";
  33     char line[128];
  34     FILE *file;
  35
  36     file = fopen(filename, "r");
  37     if (!file) {
  38         if (errno == ENOENT) {
  39             VLOG_DBG("not running on a XenServer");
  40         } else {
  41             VLOG_INFO("%s: open: %s", filename, strerror(errno));
  42         }
  43         return NULL;
  44     }
  45
  46     while (fgets(line, sizeof line, file)) {
  47         static const char leader[] = "INSTALLATION_UUID='";
  48         const int leader_len = strlen(leader);
  49         const int uuid_len = 36;
  50         static const char trailer[] = "'\n";
  51         const int trailer_len = strlen(trailer);
  52
  53         if (strlen(line) == leader_len + uuid_len + trailer_len
  54             && !memcmp(line, leader, leader_len)
  55             && !memcmp(line + leader_len + uuid_len, trailer, trailer_len)) {
  56             char *host_uuid = xmemdup0(line + leader_len, uuid_len);
  57             VLOG_INFO("running on XenServer, host-uuid %s", host_uuid);
  58             fclose(file);
  59             return host_uuid;
  60         }
  61     }
  62     fclose(file);
  63     VLOG_ERR("%s: INSTALLATION_UUID not found", filename);
  64     return NULL;
  65 }
  66
  67 const char *
  68 xenserver_get_host_uuid(void)
  69 {
  70     static char *host_uuid;
  71     static bool inited;
  72
  73     if (!inited) {
  74         host_uuid = read_host_uuid();
  75         inited = true;
  76     }
  77     return host_uuid;
  78 }
  79