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_utils.h"
  33 #include "../../logging.h"
  34 #include "volume_id/volume_id.h"
  35
  36 #define BLKGETSIZE64 _IOR(0x12,114,size_t)
  37
  38 #ifdef USE_LOG
  39 void log_message(int priority, const char *format, ...)
  40 {
  41         va_list args;
  42         static int udev_log = -1;
  43
  44         if (udev_log == -1) {
  45                 const char *value;
  46
  47                 value = getenv("UDEV_LOG");
  48                 if (value)
  49                         udev_log = log_priority(value);
  50                 else
  51                         udev_log = LOG_ERR;
  52         }
  53
  54         if (priority > udev_log)
  55                 return;
  56
  57         va_start(args, format);
  58         vsyslog(priority, format, args);
  59         va_end(args);
  60 }
  61 #endif
  62
  63 static void set_str(char *to, const char *from, size_t count)
  64 {
  65         size_t i, j, len;
  66
  67         /* strip trailing whitespace */
  68         len = strnlen(from, count);
  69         while (len && isspace(from[len-1]))
  70                 len--;
  71
  72         /* strip leading whitespace */
  73         i = 0;
  74         while (isspace(from[i]) && (i < len))
  75                 i++;
  76
  77         j = 0;
  78         while (i < len) {
  79                 /* substitute multiple whitespace */
  80                 if (isspace(from[i])) {
  81                         while (isspace(from[i]))
  82                                 i++;
  83                         to[j++] = '_';
  84                 }
  85                 /* skip chars */
  86                 if (from[i] == '/') {
  87                         i++;
  88                         continue;
  89                 }
  90                 to[j++] = from[i++];
  91         }
  92         to[j] = '\0';
  93 }
  94
  95 int main(int argc, char *argv[])
  96 {
  97         const char help[] = "usage: vol_id [--export|-t|-l|-u] <device>\n"
  98                             "       --export\n"
  99                             "       -t filesystem type\n"
 100                             "       -l filesystem label\n"
 101                             "       -u filesystem uuid\n"
 102                             "\n";
 103         enum print_type {
 104                 PRINT_EXPORT,
 105                 PRINT_TYPE,
 106                 PRINT_LABEL,
 107                 PRINT_UUID,
 108         } print = PRINT_EXPORT;
 109         struct volume_id *vid = NULL;
 110         static char name[VOLUME_ID_LABEL_SIZE];
 111         int i;
 112         uint64_t size;
 113         const char *node = NULL;
 114         int rc = 0;
 115
 116         logging_init("vol_id");
 117
 118         for (i = 1 ; i < argc; i++) {
 119                 char *arg = argv[i];
 120
 121                 if (strcmp(arg, "--export") == 0) {
 122                         print = PRINT_EXPORT;
 123                 } else if (strcmp(arg, "-t") == 0) {
 124                         print = PRINT_TYPE;
 125                 } else if (strcmp(arg, "-l") == 0) {
 126                         print = PRINT_LABEL;
 127                 } else if (strcmp(arg, "-u") == 0) {
 128                         print = PRINT_UUID;
 129                 } else
 130                         node = arg;
 131         }
 132         if (!node) {
 133                 err("no node specified");
 134                 fprintf(stderr, help);
 135                 rc = 1;
 136                 goto exit;
 137         }
 138
 139         vid = volume_id_open_node(node);
 140         if (vid == NULL) {
 141                 fprintf(stderr, "%s: error open volume\n", node);
 142                 rc = 2;
 143                 goto exit;
 144         }
 145
 146         if (ioctl(vid->fd, BLKGETSIZE64, &size) != 0)
 147                 size = 0;
 148         dbg("BLKGETSIZE64=%llu", size);
 149
 150         if (volume_id_probe_all(vid, 0, size) == 0)
 151                 goto print;
 152
 153         if (print != PRINT_EXPORT)
 154                 fprintf(stderr, "%s: unknown volume type\n", node);
 155         rc = 3;
 156         goto exit;
 157
 158 print:
 159         set_str(name, vid->label, sizeof(vid->label));
 160         replace_untrusted_chars(name);
 161
 162         switch (print) {
 163         case PRINT_EXPORT:
 164                 printf("ID_FS_USAGE=%s\n", vid->usage);
 165                 printf("ID_FS_TYPE=%s\n", vid->type);
 166                 printf("ID_FS_VERSION=%s\n", vid->type_version);
 167                 printf("ID_FS_UUID=%s\n", vid->uuid);
 168                 printf("ID_FS_LABEL=%s\n", vid->label);
 169                 printf("ID_FS_LABEL_SAFE=%s\n", name);
 170                 break;
 171         case PRINT_TYPE:
 172                 printf("%s\n", vid->type);
 173                 break;
 174         case PRINT_LABEL:
 175                 if (name[0] == '\0' ||
 176                     (vid->usage_id != VOLUME_ID_FILESYSTEM && vid->usage_id != VOLUME_ID_DISKLABEL)) {
 177                         rc = 3;
 178                         goto exit;
 179                 }
 180                 printf("%s\n", name);
 181                 break;
 182         case PRINT_UUID:
 183                 if (vid->uuid[0] == '\0' || vid->usage_id != VOLUME_ID_FILESYSTEM) {
 184                         rc = 4;
 185                         goto exit;
 186                 }
 187                 printf("%s\n", vid->uuid);
 188                 break;
 189         }
 190
 191 exit:
 192         if (vid != NULL)
 193                 volume_id_close(vid);
 194
 195         logging_close();
 196         return rc;
 197 }