extras/volume_id/vol_id.c

   1 /*
   2  * vol_id - udev callout to read filesystem label and uuid
   3  *
   4  * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  *      This program is free software; you can redistribute it and/or modify it
   7  *      under the terms of the GNU General Public License as published by the
   8  *      Free Software Foundation version 2 of the License.
   9  *
  10  *      This program is distributed in the hope that it will be useful, but
  11  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  *      General Public License for more details.
  14  *
  15  *      You should have received a copy of the GNU General Public License along
  16  *      with this program; if not, write to the Free Software Foundation, Inc.,
  17  *      675 Mass Ave, Cambridge, MA 02139, USA.
  18  *
  19  */
  20
  21 #ifndef _GNU_SOURCE
  22 #define _GNU_SOURCE 1
  23 #endif
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28 #include <string.h>
  29 #include <ctype.h>
  30 #include <sys/ioctl.h>
  31
  32 #include "../../udev.h"
  33 #include "libvolume_id/volume_id.h"
  34
  35 #define BLKGETSIZE64 _IOR(0x12,114,size_t)
  36
  37 #ifdef USE_LOG
  38 void log_message(int priority, const char *format, ...)
  39 {
  40         va_list args;
  41         static int udev_log = -1;
  42
  43         if (udev_log == -1) {
  44                 const char *value;
  45
  46                 value = getenv("UDEV_LOG");
  47                 if (value)
  48                         udev_log = log_priority(value);
  49                 else
  50                         udev_log = LOG_ERR;
  51         }
  52
  53         if (priority > udev_log)
  54                 return;
  55
  56         va_start(args, format);
  57         vsyslog(priority, format, args);
  58         va_end(args);
  59 }
  60 #endif
  61
  62 static void set_str(char *to, const char *from, size_t count)
  63 {
  64         size_t i, j, len;
  65
  66         /* strip trailing whitespace */
  67         len = strnlen(from, count);
  68         while (len && isspace(from[len-1]))
  69                 len--;
  70
  71         /* strip leading whitespace */
  72         i = 0;
  73         while (isspace(from[i]) && (i < len))
  74                 i++;
  75
  76         j = 0;
  77         while (i < len) {
  78                 /* substitute multiple whitespace */
  79                 if (isspace(from[i])) {
  80                         while (isspace(from[i]))
  81                                 i++;
  82                         to[j++] = '_';
  83                 }
  84                 /* skip chars */
  85                 if (from[i] == '/') {
  86                         i++;
  87                         continue;
  88                 }
  89                 to[j++] = from[i++];
  90         }
  91         to[j] = '\0';
  92 }
  93
  94 int main(int argc, char *argv[])
  95 {
  96         const char help[] = "usage: vol_id [--export|-t|-l|-u] <device>\n"
  97                             "       --export\n"
  98                             "       -t filesystem type\n"
  99                             "       -l filesystem label\n"
 100                             "       -u filesystem uuid\n"
 101                             "\n";
 102         enum print_type {
 103                 PRINT_EXPORT,
 104                 PRINT_TYPE,
 105                 PRINT_LABEL,
 106                 PRINT_UUID,
 107         } print = PRINT_EXPORT;
 108         struct volume_id *vid = NULL;
 109         static char name[VOLUME_ID_LABEL_SIZE];
 110         int i;
 111         uint64_t size;
 112         const char *node = NULL;
 113         int rc = 0;
 114
 115         logging_init("vol_id");
 116
 117         for (i = 1 ; i < argc; i++) {
 118                 char *arg = argv[i];
 119
 120                 if (strcmp(arg, "--export") == 0) {
 121                         print = PRINT_EXPORT;
 122                 } else if (strcmp(arg, "-t") == 0) {
 123                         print = PRINT_TYPE;
 124                 } else if (strcmp(arg, "-l") == 0) {
 125                         print = PRINT_LABEL;
 126                 } else if (strcmp(arg, "-u") == 0) {
 127                         print = PRINT_UUID;
 128                 } else
 129                         node = arg;
 130         }
 131         if (!node) {
 132                 err("no node specified");
 133                 fprintf(stderr, help);
 134                 rc = 1;
 135                 goto exit;
 136         }
 137
 138         vid = volume_id_open_node(node);
 139         if (vid == NULL) {
 140                 fprintf(stderr, "%s: error open volume\n", node);
 141                 rc = 2;
 142                 goto exit;
 143         }
 144
 145         if (ioctl(vid->fd, BLKGETSIZE64, &size) != 0)
 146                 size = 0;
 147         dbg("BLKGETSIZE64=%llu", size);
 148
 149         if (volume_id_probe_all(vid, 0, size) == 0)
 150                 goto print;
 151
 152         if (print != PRINT_EXPORT)
 153                 fprintf(stderr, "%s: unknown volume type\n", node);
 154         rc = 3;
 155         goto exit;
 156
 157 print:
 158         set_str(name, vid->label, sizeof(vid->label));
 159         replace_untrusted_chars(name);
 160
 161         switch (print) {
 162         case PRINT_EXPORT:
 163                 printf("ID_FS_USAGE=%s\n", vid->usage);
 164                 printf("ID_FS_TYPE=%s\n", vid->type);
 165                 printf("ID_FS_VERSION=%s\n", vid->type_version);
 166                 printf("ID_FS_UUID=%s\n", vid->uuid);
 167                 printf("ID_FS_LABEL=%s\n", vid->label);
 168                 printf("ID_FS_LABEL_SAFE=%s\n", name);
 169                 break;
 170         case PRINT_TYPE:
 171                 printf("%s\n", vid->type);
 172                 break;
 173         case PRINT_LABEL:
 174                 if (name[0] == '\0' ||
 175                     (vid->usage_id != VOLUME_ID_FILESYSTEM && vid->usage_id != VOLUME_ID_DISKLABEL)) {
 176                         rc = 3;
 177                         goto exit;
 178                 }
 179                 printf("%s\n", name);
 180                 break;
 181         case PRINT_UUID:
 182                 if (vid->uuid[0] == '\0' || vid->usage_id != VOLUME_ID_FILESYSTEM) {
 183                         rc = 4;
 184                         goto exit;
 185                 }
 186                 printf("%s\n", vid->uuid);
 187                 break;
 188         }
 189
 190 exit:
 191         if (vid != NULL)
 192                 volume_id_close(vid);
 193
 194         logging_close();
 195         return rc;
 196 }