git.sesse.net Git - bcachefs-tools-debian/blob - probe-bcache.c

   1 /*
   2  * Author: Kent Overstreet <kmo@daterainc.com>
   3  *
   4  * GPLv2
   5  */
   6
   7 #define _FILE_OFFSET_BITS       64
   8 #define __USE_FILE_OFFSET64
   9 #define _XOPEN_SOURCE 500
  10
  11 #include <fcntl.h>
  12 #include <linux/fs.h>
  13 #include <stdbool.h>
  14 #include <stdint.h>
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <sys/ioctl.h>
  19 #include <sys/types.h>
  20 #include <sys/stat.h>
  21 #include <unistd.h>
  22 #include <uuid/uuid.h>
  23
  24 #include "bcache.h"
  25
  26 int main(int argc, char **argv)
  27 {
  28         bool udev = false;
  29         int i, o;
  30         extern char *optarg;
  31         struct cache_sb sb;
  32         char uuid[40];
  33
  34         while ((o = getopt(argc, argv, "o:")) != EOF)
  35                 switch (o) {
  36                 case 'o':
  37                         if (strcmp("udev", optarg)) {
  38                                 printf("Invalid output format %s\n", optarg);
  39                                 exit(EXIT_FAILURE);
  40                         }
  41                         udev = true;
  42                         break;
  43                 }
  44
  45
  46         argv += optind;
  47         argc -= optind;
  48
  49         for (i = 0; i < argc; i++) {
  50                 int fd = open(argv[i], O_RDONLY);
  51                 if (fd == -1)
  52                         continue;
  53
  54
  55                 if (pread(fd, &sb, sizeof(sb), 4096) != sizeof(sb))
  56                         continue;
  57
  58                 if (memcmp(sb.magic, bcache_magic, 16))
  59                         continue;
  60
  61                 uuid_unparse(sb.uuid, uuid);
  62
  63                 if (udev)
  64                         printf("ID_FS_UUID=%s\n"
  65                                "ID_FS_UUID_ENC=%s\n"
  66                                "ID_FS_TYPE=bcache\n",
  67                                uuid, uuid);
  68                 else
  69                         printf("%s: UUID=\"\" TYPE=\"bcache\"\n", uuid);
  70         }
  71
  72         return 0;
  73 }