lib/blkid/probe.c

   1 /*
   2  * probe.c - identify a block device by its contents, and return a dev
   3  *           struct with the details
   4  *
   5  * Copyright (C) 1999 by Andries Brouwer
   6  * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o
   7  * Copyright (C) 2001 by Andreas Dilger
   8  *
   9  * %Begin-Header%
  10  * This file may be redistributed under the terms of the
  11  * GNU Lesser General Public License.
  12  * %End-Header%
  13  */
  14
  15 #include <stdio.h>
  16 #include <string.h>
  17 #include <stdlib.h>
  18 #include <unistd.h>
  19 #include <fcntl.h>
  20 #include <sys/types.h>
  21 #ifdef HAVE_SYS_STAT_H
  22 #include <sys/stat.h>
  23 #endif
  24 #ifdef HAVE_SYS_MKDEV_H
  25 #include <sys/mkdev.h>
  26 #endif
  27 #ifdef HAVE_ERRNO_H
  28 #include <errno.h>
  29 #endif
  30 #include "blkidP.h"
  31 #include "uuid/uuid.h"
  32 #include "probe.h"
  33
  34 /*
  35  * This is a special case code to check for an MDRAID device.  We do
  36  * this special since it requires checking for a superblock at the end
  37  * of the device.
  38  */
  39 static int check_mdraid(int fd, unsigned char *ret_uuid)
  40 {
  41         struct mdp_superblock_s *md;
  42         blkid_loff_t            offset;
  43         char                    buf[4096];
  44
  45         if (fd < 0)
  46                 return -BLKID_ERR_PARAM;
  47
  48         offset = (blkid_get_dev_size(fd) & ~((blkid_loff_t)65535)) - 65536;
  49
  50         if (blkid_llseek(fd, offset, 0) < 0 ||
  51             read(fd, buf, 4096) != 4096)
  52                 return -BLKID_ERR_IO;
  53
  54         /* Check for magic number */
  55         if (memcmp("\251+N\374", buf, 4))
  56                 return -BLKID_ERR_PARAM;
  57
  58         if (!ret_uuid)
  59                 return 0;
  60         *ret_uuid = 0;
  61
  62         /* The MD UUID is not contiguous in the superblock, make it so */
  63         md = (struct mdp_superblock_s *)buf;
  64         if (md->set_uuid0 || md->set_uuid1 || md->set_uuid2 || md->set_uuid3) {
  65                 memcpy(ret_uuid, &md->set_uuid0, 4);
  66                 memcpy(ret_uuid, &md->set_uuid1, 12);
  67         }
  68         return 0;
  69 }
  70
  71 static void set_uuid(blkid_dev dev, uuid_t uuid)
  72 {
  73         char    str[37];
  74
  75         if (!uuid_is_null(uuid)) {
  76                 uuid_unparse(uuid, str);
  77                 blkid_set_tag(dev, "UUID", str, sizeof(str));
  78         }
  79 }
  80
  81 static int probe_ext2(int fd __BLKID_ATTR((unused)),
  82                       blkid_cache cache __BLKID_ATTR((unused)),
  83                       blkid_dev dev,
  84                       struct blkid_magic *id, unsigned char *buf)
  85 {
  86         struct ext2_super_block *es;
  87         const char *sec_type = 0, *label = 0;
  88
  89         es = (struct ext2_super_block *)buf;
  90
  91         DBG(DEBUG_PROBE, printf("ext2_sb.compat = %08X:%08X:%08X\n",
  92                    blkid_le32(es->s_feature_compat),
  93                    blkid_le32(es->s_feature_incompat),
  94                    blkid_le32(es->s_feature_ro_compat)));
  95
  96         /* Distinguish between jbd and ext2/3 fs */
  97         if (id && (blkid_le32(es->s_feature_incompat) &
  98                    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV))
  99                 return -BLKID_ERR_PARAM;
 100
 101         if (strlen(es->s_volume_name))
 102                 label = es->s_volume_name;
 103         blkid_set_tag(dev, "LABEL", label, sizeof(es->s_volume_name));
 104
 105         set_uuid(dev, es->s_uuid);
 106
 107         if (blkid_le32(es->s_feature_compat) &
 108             EXT3_FEATURE_COMPAT_HAS_JOURNAL)
 109                 sec_type = "ext3";
 110
 111         blkid_set_tag(dev, "SEC_TYPE", sec_type, 0);
 112
 113         return 0;
 114 }
 115
 116 static int probe_jbd(int fd __BLKID_ATTR((unused)),
 117                      blkid_cache cache __BLKID_ATTR((unused)),
 118                      blkid_dev dev,
 119                      struct blkid_magic *id __BLKID_ATTR((unused)),
 120                      unsigned char *buf)
 121 {
 122         struct ext2_super_block *es = (struct ext2_super_block *) buf;
 123
 124         if (!(blkid_le32(es->s_feature_incompat) &
 125               EXT3_FEATURE_INCOMPAT_JOURNAL_DEV))
 126                 return -BLKID_ERR_PARAM;
 127
 128         return (probe_ext2(fd, cache, dev, 0, buf));
 129 }
 130
 131 static int probe_vfat(int fd __BLKID_ATTR((unused)),
 132                       blkid_cache cache __BLKID_ATTR((unused)),
 133                       blkid_dev dev,
 134                       struct blkid_magic *id __BLKID_ATTR((unused)),
 135                       unsigned char *buf)
 136 {
 137         struct vfat_super_block *vs;
 138         char serno[10];
 139         const char *label = 0;
 140
 141         vs = (struct vfat_super_block *)buf;
 142
 143         if (strncmp(vs->vs_label, "NO NAME", 7)) {
 144                 char *end = vs->vs_label + sizeof(vs->vs_label) - 1;
 145
 146                 while (*end == ' ' && end >= vs->vs_label)
 147                         --end;
 148                 if (end >= vs->vs_label)
 149                         label = vs->vs_label;
 150                 blkid_set_tag(dev, "LABEL", label, end - vs->vs_label + 1);
 151         }
 152
 153         /* We can't just print them as %04X, because they are unaligned */
 154         sprintf(serno, "%02X%02X-%02X%02X", vs->vs_serno[3], vs->vs_serno[2],
 155                 vs->vs_serno[1], vs->vs_serno[0]);
 156         blkid_set_tag(dev, "UUID", serno, sizeof(serno));
 157
 158         return 0;
 159 }
 160
 161 static int probe_msdos(int fd __BLKID_ATTR((unused)),
 162                        blkid_cache cache __BLKID_ATTR((unused)),
 163                        blkid_dev dev,
 164                        struct blkid_magic *id __BLKID_ATTR((unused)),
 165                        unsigned char *buf)
 166 {
 167         struct msdos_super_block *ms = (struct msdos_super_block *) buf;
 168         char serno[10];
 169         const char *label = 0;
 170
 171         if (strncmp(ms->ms_label, "NO NAME", 7)) {
 172                 char *end = ms->ms_label + sizeof(ms->ms_label) - 1;
 173
 174                 while (*end == ' ' && end >= ms->ms_label)
 175                         --end;
 176                 if (end >= ms->ms_label)
 177                         label = ms->ms_label;
 178                 blkid_set_tag(dev, "LABEL", label, end - ms->ms_label + 1);
 179         }
 180
 181         /* We can't just print them as %04X, because they are unaligned */
 182         sprintf(serno, "%02X%02X-%02X%02X", ms->ms_serno[3], ms->ms_serno[2],
 183                 ms->ms_serno[1], ms->ms_serno[0]);
 184         blkid_set_tag(dev, "UUID", serno, 0);
 185
 186         return 0;
 187 }
 188
 189 static int probe_xfs(int fd __BLKID_ATTR((unused)),
 190                      blkid_cache cache __BLKID_ATTR((unused)),
 191                      blkid_dev dev,
 192                      struct blkid_magic *id __BLKID_ATTR((unused)),
 193                      unsigned char *buf)
 194 {
 195         struct xfs_super_block *xs;
 196         const char *label = 0;
 197
 198         xs = (struct xfs_super_block *)buf;
 199
 200         if (strlen(xs->xs_fname))
 201                 label = xs->xs_fname;
 202         blkid_set_tag(dev, "LABEL", label, sizeof(xs->xs_fname));
 203         set_uuid(dev, xs->xs_uuid);
 204         return 0;
 205 }
 206
 207 static int probe_reiserfs(int fd __BLKID_ATTR((unused)),
 208                           blkid_cache cache __BLKID_ATTR((unused)),
 209                           blkid_dev dev,
 210                           struct blkid_magic *id, unsigned char *buf)
 211 {
 212         struct reiserfs_super_block *rs = (struct reiserfs_super_block *) buf;
 213         unsigned int blocksize;
 214         const char *label = 0;
 215
 216         blocksize = blkid_le16(rs->rs_blocksize);
 217
 218         /* If the superblock is inside the journal, we have the wrong one */
 219         if (id->bim_kboff/(blocksize>>10) > blkid_le32(rs->rs_journal_block))
 220                 return -BLKID_ERR_BIG;
 221
 222         /* LABEL/UUID are only valid for later versions of Reiserfs v3.6. */
 223         if (!strcmp(id->bim_magic, "ReIsEr2Fs") ||
 224             !strcmp(id->bim_magic, "ReIsEr3Fs")) {
 225                 if (strlen(rs->rs_label))
 226                         label = rs->rs_label;
 227                 blkid_set_tag(dev, "LABEL", label, sizeof(rs->rs_label));
 228                 set_uuid(dev, rs->rs_uuid);
 229         }
 230
 231         return 0;
 232 }
 233
 234 static int probe_jfs(int fd __BLKID_ATTR((unused)),
 235                      blkid_cache cache __BLKID_ATTR((unused)),
 236                      blkid_dev dev,
 237                      struct blkid_magic *id __BLKID_ATTR((unused)),
 238                      unsigned char *buf)
 239 {
 240         struct jfs_super_block *js;
 241         const char *label = 0;
 242
 243         js = (struct jfs_super_block *)buf;
 244
 245         if (strlen((char *) js->js_label))
 246                 label = (char *) js->js_label;
 247         blkid_set_tag(dev, "LABEL", label, sizeof(js->js_label));
 248         set_uuid(dev, js->js_uuid);
 249         return 0;
 250 }
 251
 252 static int probe_romfs(int fd __BLKID_ATTR((unused)),
 253                        blkid_cache cache __BLKID_ATTR((unused)),
 254                        blkid_dev dev,
 255                        struct blkid_magic *id __BLKID_ATTR((unused)),
 256                        unsigned char *buf)
 257 {
 258         struct romfs_super_block *ros;
 259         const char *label = 0;
 260
 261         ros = (struct romfs_super_block *)buf;
 262
 263         if (strlen((char *) ros->ros_volume))
 264                 label = (char *) ros->ros_volume;
 265         blkid_set_tag(dev, "LABEL", label, strlen(label));
 266         return 0;
 267 }
 268
 269 static const char
 270 *udf_magic[] = { "BEA01", "BOOT2", "CD001", "CDW02", "NSR02",
 271                  "NSR03", "TEA01", 0 };
 272
 273 static int probe_udf(int fd, blkid_cache cache __BLKID_ATTR((unused)),
 274                      blkid_dev dev __BLKID_ATTR((unused)),
 275                        struct blkid_magic *id __BLKID_ATTR((unused)),
 276                      unsigned char *buf __BLKID_ATTR((unused)))
 277 {
 278         int j, bs;
 279         struct iso_volume_descriptor isosb;
 280         const char ** m;
 281
 282         /* determine the block size by scanning in 2K increments
 283            (block sizes larger than 2K will be null padded) */
 284         for (bs = 1; bs < 16; bs++) {
 285                 lseek(fd, bs*2048+32768, SEEK_SET);
 286                 if (read(fd, (char *)&isosb, sizeof(isosb)) != sizeof(isosb))
 287                         return 1;
 288                 if (isosb.id[0])
 289                         break;
 290         }
 291
 292         /* Scan up to another 64 blocks looking for additional VSD's */
 293         for (j = 1; j < 64; j++) {
 294                 if (j > 1) {
 295                         lseek(fd, j*bs*2048+32768, SEEK_SET);
 296                         if (read(fd, (char *)&isosb, sizeof(isosb))
 297                             != sizeof(isosb))
 298                                 return 1;
 299                 }
 300                 /* If we find NSR0x then call it udf:
 301                    NSR01 for UDF 1.00
 302                    NSR02 for UDF 1.50
 303                    NSR03 for UDF 2.00 */
 304                 if (!strncmp(isosb.id, "NSR0", 4))
 305                         return 0;
 306                 for (m = udf_magic; *m; m++)
 307                         if (!strncmp(*m, isosb.id, 5))
 308                                 break;
 309                 if (*m == 0)
 310                         return 1;
 311         }
 312         return 1;
 313 }
 314
 315 static int probe_ocfs(int fd __BLKID_ATTR((unused)),
 316                       blkid_cache cache __BLKID_ATTR((unused)),
 317                       blkid_dev dev,
 318                       struct blkid_magic *id __BLKID_ATTR((unused)),
 319                       unsigned char *buf)
 320 {
 321         struct ocfs_volume_header ovh;
 322         struct ocfs_volume_label ovl;
 323         __u32 major;
 324
 325         memcpy(&ovh, buf, sizeof(ovh));
 326         memcpy(&ovl, buf+512, sizeof(ovl));
 327
 328         major = ocfsmajor(ovh);
 329         if (major == 1)
 330                 blkid_set_tag(dev,"SEC_TYPE","ocfs1",sizeof("ocfs1"));
 331         else if (major >= 9)
 332                 blkid_set_tag(dev,"SEC_TYPE","ntocfs",sizeof("ntocfs"));
 333
 334         blkid_set_tag(dev, "LABEL", ovl.label, ocfslabellen(ovl));
 335         blkid_set_tag(dev, "MOUNT", ovh.mount, ocfsmountlen(ovh));
 336         set_uuid(dev, ovl.vol_id);
 337         return 0;
 338 }
 339
 340 static int probe_ocfs2(int fd __BLKID_ATTR((unused)),
 341                       blkid_cache cache __BLKID_ATTR((unused)),
 342                       blkid_dev dev,
 343                       struct blkid_magic *id __BLKID_ATTR((unused)),
 344                       unsigned char *buf)
 345 {
 346         struct ocfs2_super_block *osb;
 347
 348         osb = (struct ocfs2_super_block *)buf;
 349
 350         blkid_set_tag(dev, "LABEL", osb->s_label, sizeof(osb->s_label));
 351         set_uuid(dev, osb->s_uuid);
 352         return 0;
 353 }
 354
 355 /*
 356  * BLKID_BLK_OFFS is at least as large as the highest bim_kboff defined
 357  * in the type_array table below + bim_kbalign.
 358  *
 359  * When probing for a lot of magics, we handle everything in 1kB buffers so
 360  * that we don't have to worry about reading each combination of block sizes.
 361  */
 362 #define BLKID_BLK_OFFS  64      /* currently reiserfs */
 363
 364 /*
 365  * Various filesystem magics that we can check for.  Note that kboff and
 366  * sboff are in kilobytes and bytes respectively.  All magics are in
 367  * byte strings so we don't worry about endian issues.
 368  */
 369 static struct blkid_magic type_array[] = {
 370 /*  type     kboff   sboff len  magic                   probe */
 371   { "jbd",       1,   0x38,  2, "\123\357",             probe_jbd },
 372   { "ext2",      1,   0x38,  2, "\123\357",             probe_ext2 },
 373   { "reiserfs",  8,   0x34,  8, "ReIsErFs",             probe_reiserfs },
 374   { "reiserfs", 64,   0x34,  9, "ReIsEr2Fs",            probe_reiserfs },
 375   { "reiserfs", 64,   0x34,  9, "ReIsEr3Fs",            probe_reiserfs },
 376   { "reiserfs", 64,   0x34,  8, "ReIsErFs",             probe_reiserfs },
 377   { "reiserfs",  8,     20,  8, "ReIsErFs",             probe_reiserfs },
 378   { "ntfs",      0,      3,  8, "NTFS    ",             0 },
 379   { "vfat",      0,   0x52,  5, "MSWIN",                probe_vfat },
 380   { "vfat",      0,   0x52,  8, "FAT32   ",             probe_vfat },
 381   { "msdos",     0,   0x36,  5, "MSDOS",                probe_msdos },
 382   { "msdos",     0,   0x36,  8, "FAT16   ",             probe_msdos },
 383   { "msdos",     0,   0x36,  8, "FAT12   ",             probe_msdos },
 384   { "minix",     1,   0x10,  2, "\177\023",             0 },
 385   { "minix",     1,   0x10,  2, "\217\023",             0 },
 386   { "minix",     1,   0x10,  2, "\150\044",             0 },
 387   { "minix",     1,   0x10,  2, "\170\044",             0 },
 388   { "vxfs",      1,      0,  4, "\365\374\001\245",     0 },
 389   { "xfs",       0,      0,  4, "XFSB",                 probe_xfs },
 390   { "romfs",     0,      0,  8, "-rom1fs-",             probe_romfs },
 391   { "bfs",       0,      0,  4, "\316\372\173\033",     0 },
 392   { "cramfs",    0,      0,  4, "E=\315\034",           0 },
 393   { "qnx4",      0,      4,  6, "QNX4FS",               0 },
 394   { "udf",      32,      1,  5, "BEA01",                probe_udf },
 395   { "udf",      32,      1,  5, "BOOT2",                probe_udf },
 396   { "udf",      32,      1,  5, "CD001",                probe_udf },
 397   { "udf",      32,      1,  5, "CDW02",                probe_udf },
 398   { "udf",      32,      1,  5, "NSR02",                probe_udf },
 399   { "udf",      32,      1,  5, "NSR03",                probe_udf },
 400   { "udf",      32,      1,  5, "TEA01",                probe_udf },
 401   { "iso9660",  32,      1,  5, "CD001",                0 },
 402   { "iso9660",  32,      9,  5, "CDROM",                0 },
 403   { "jfs",      32,      0,  4, "JFS1",                 probe_jfs },
 404   { "hfs",       1,      0,  2, "BD",                   0 },
 405   { "ufs",       8,  0x55c,  4, "T\031\001\000",        0 },
 406   { "hpfs",      8,      0,  4, "I\350\225\371",        0 },
 407   { "sysv",      0,  0x3f8,  4, "\020~\030\375",        0 },
 408   { "swap",      0,  0xff6, 10, "SWAP-SPACE",           0 },
 409   { "swap",      0,  0xff6, 10, "SWAPSPACE2",           0 },
 410   { "swap",      0, 0x1ff6, 10, "SWAP-SPACE",           0 },
 411   { "swap",      0, 0x1ff6, 10, "SWAPSPACE2",           0 },
 412   { "swap",      0, 0x3ff6, 10, "SWAP-SPACE",           0 },
 413   { "swap",      0, 0x3ff6, 10, "SWAPSPACE2",           0 },
 414   { "ocfs",      0,      8,  9,  "OracleCFS",           probe_ocfs },
 415   { "ocfs2",     1,      0,  6,  "OCFSV2",              probe_ocfs2 },
 416   { "ocfs2",     2,      0,  6,  "OCFSV2",              probe_ocfs2 },
 417   { "ocfs2",     4,      0,  6,  "OCFSV2",              probe_ocfs2 },
 418   { "ocfs2",     8,      0,  6,  "OCFSV2",              probe_ocfs2 },
 419   {   NULL,      0,      0,  0, NULL,                   NULL }
 420 };
 421
 422 /*
 423  * Verify that the data in dev is consistent with what is on the actual
 424  * block device (using the devname field only).  Normally this will be
 425  * called when finding items in the cache, but for long running processes
 426  * is also desirable to revalidate an item before use.
 427  *
 428  * If we are unable to revalidate the data, we return the old data and
 429  * do not set the BLKID_BID_FL_VERIFIED flag on it.
 430  */
 431 blkid_dev blkid_verify_devname(blkid_cache cache, blkid_dev dev)
 432 {
 433         struct blkid_magic *id;
 434         unsigned char *bufs[BLKID_BLK_OFFS + 1], *buf;
 435         const char *type;
 436         struct stat st;
 437         time_t diff, now;
 438         int fd, idx;
 439
 440         if (!dev)
 441                 return NULL;
 442
 443         now = time(0);
 444         diff = now - dev->bid_time;
 445
 446         if ((now < dev->bid_time) ||
 447             (diff < BLKID_PROBE_MIN) ||
 448             (dev->bid_flags & BLKID_BID_FL_VERIFIED &&
 449              diff < BLKID_PROBE_INTERVAL))
 450                 return dev;
 451
 452         DBG(DEBUG_PROBE,
 453             printf("need to revalidate %s (time since last check %lu)\n",
 454                    dev->bid_name, diff));
 455
 456         if (((fd = open(dev->bid_name, O_RDONLY)) < 0) ||
 457             (fstat(fd, &st) < 0) || !S_ISBLK(st.st_mode)) {
 458                 if (errno == ENXIO || errno == ENODEV || errno == ENOENT) {
 459                         blkid_free_dev(dev);
 460                         return NULL;
 461                 }
 462                 /* We don't have read permission, just return cache data. */
 463                 DBG(DEBUG_PROBE,
 464                     printf("returning unverified data for %s\n",
 465                            dev->bid_name));
 466                 return dev;
 467         }
 468
 469         memset(bufs, 0, sizeof(bufs));
 470
 471         /*
 472          * Iterate over the type array.  If we already know the type,
 473          * then try that first.  If it doesn't work, then blow away
 474          * the type information, and try again.
 475          *
 476          */
 477 try_again:
 478         type = 0;
 479         if (!dev->bid_type || !strcmp(dev->bid_type, "mdraid")) {
 480                 uuid_t  uuid;
 481
 482                 if (check_mdraid(fd, uuid) == 0) {
 483                         set_uuid(dev, uuid);
 484                         type = "mdraid";
 485                         goto found_type;
 486                 }
 487         }
 488         for (id = type_array; id->bim_type; id++) {
 489                 if (dev->bid_type &&
 490                     strcmp(id->bim_type, dev->bid_type))
 491                         continue;
 492
 493                 idx = id->bim_kboff + (id->bim_sboff >> 10);
 494                 if (idx > BLKID_BLK_OFFS || idx < 0)
 495                         continue;
 496                 buf = bufs[idx];
 497                 if (!buf) {
 498                         if (lseek(fd, idx << 10, SEEK_SET) < 0)
 499                                 continue;
 500
 501                         if (!(buf = (unsigned char *)malloc(1024)))
 502                                 continue;
 503
 504                         if (read(fd, buf, 1024) != 1024) {
 505                                 free(buf);
 506                                 continue;
 507                         }
 508                         bufs[idx] = buf;
 509                 }
 510
 511                 if (memcmp(id->bim_magic, buf + (id->bim_sboff&0x3ff),
 512                            id->bim_len))
 513                         continue;
 514
 515                 if ((id->bim_probe == NULL) ||
 516                     (id->bim_probe(fd, cache, dev, id, buf) == 0)) {
 517                         type = id->bim_type;
 518                         goto found_type;
 519                 }
 520         }
 521
 522         if (!id->bim_type && dev->bid_type) {
 523                 /*
 524                  * Zap the device filesystem type and try again
 525                  */
 526                 blkid_set_tag(dev, "TYPE", 0, 0);
 527                 blkid_set_tag(dev, "SEC_TYPE", 0, 0);
 528                 blkid_set_tag(dev, "LABEL", 0, 0);
 529                 blkid_set_tag(dev, "UUID", 0, 0);
 530                 goto try_again;
 531         }
 532
 533         if (!dev->bid_type) {
 534                 blkid_free_dev(dev);
 535                 return NULL;
 536         }
 537
 538 found_type:
 539         if (dev && type) {
 540                 dev->bid_devno = st.st_rdev;
 541                 dev->bid_time = time(0);
 542                 dev->bid_flags |= BLKID_BID_FL_VERIFIED;
 543                 cache->bic_flags |= BLKID_BIC_FL_CHANGED;
 544
 545                 blkid_set_tag(dev, "TYPE", type, 0);
 546
 547                 DBG(DEBUG_PROBE, printf("%s: devno 0x%04Lx, type %s\n",
 548                            dev->bid_name, st.st_rdev, type));
 549         }
 550
 551         close(fd);
 552
 553         return dev;
 554 }
 555
 556 int blkid_known_fstype(const char *fstype)
 557 {
 558         struct blkid_magic *id;
 559
 560         for (id = type_array; id->bim_type; id++) {
 561                 if (strcmp(fstype, id->bim_type) == 0)
 562                         return 1;
 563         }
 564         return 0;
 565 }
 566
 567 #ifdef TEST_PROGRAM
 568 int main(int argc, char **argv)
 569 {
 570         blkid_dev dev;
 571         blkid_cache cache;
 572         int ret;
 573
 574         blkid_debug_mask = DEBUG_ALL;
 575         if (argc != 2) {
 576                 fprintf(stderr, "Usage: %s device\n"
 577                         "Probe a single device to determine type\n", argv[0]);
 578                 exit(1);
 579         }
 580         if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
 581                 fprintf(stderr, "%s: error creating cache (%d)\n",
 582                         argv[0], ret);
 583                 exit(1);
 584         }
 585         dev = blkid_get_dev(cache, argv[1], BLKID_DEV_NORMAL);
 586         if (!dev) {
 587                 printf("%s: %s has an unsupported type\n", argv[0], argv[1]);
 588                 return (1);
 589         }
 590         printf("%s is type %s\n", argv[1], dev->bid_type ?
 591                 dev->bid_type : "(null)");
 592         if (dev->bid_label)
 593                 printf("\tlabel is '%s'\n", dev->bid_label);
 594         if (dev->bid_uuid)
 595                 printf("\tuuid is %s\n", dev->bid_uuid);
 596
 597         blkid_free_dev(dev);
 598         return (0);
 599 }
 600 #endif