misc-utils/blkid.c

   1 /*
   2  * blkid.c - User command-line interface for libblkid
   3  *
   4  * Copyright (C) 2001 Andreas Dilger
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the
   8  * GNU Lesser General Public License.
   9  * %End-Header%
  10  */
  11
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <unistd.h>
  15 #include <string.h>
  16 #include <sys/types.h>
  17 #include <sys/stat.h>
  18 #include <fcntl.h>
  19 #include <termios.h>
  20 #include <errno.h>
  21 #ifdef HAVE_SYS_IOCTL_H
  22 #include <sys/ioctl.h>
  23 #endif
  24 #ifdef HAVE_GETOPT_H
  25 #include <getopt.h>
  26 #else
  27 extern int getopt(int argc, char * const argv[], const char *optstring);
  28 extern char *optarg;
  29 extern int optind;
  30 #endif
  31
  32 #define OUTPUT_VALUE_ONLY       0x0001
  33 #define OUTPUT_DEVICE_ONLY      0x0002
  34 #define OUTPUT_PRETTY_LIST      0x0004
  35 #define OUTPUT_UDEV_LIST        0x0008
  36
  37 #include <blkid.h>
  38
  39 #include "ismounted.h"
  40 #include "strtosize.h"
  41
  42 const char *progname = "blkid";
  43
  44 static void print_version(FILE *out)
  45 {
  46         fprintf(out, "%s from %s (libblkid %s, %s)\n",
  47                 progname, PACKAGE_STRING, LIBBLKID_VERSION, LIBBLKID_DATE);
  48 }
  49
  50 static void usage(int error)
  51 {
  52         FILE *out = error ? stderr : stdout;
  53
  54         print_version(out);
  55         fprintf(out,
  56                 "Usage:\n"
  57                 "  %1$s -L <label> | -U <uuid>\n\n"
  58                 "  %1$s [-c <file>] [-ghlLv] [-o format] [-s <tag>] \n"
  59                 "        [-t <token>] [-w <file>] [dev ...]\n\n"
  60                 "  %1$s -p [-O <offset>] [-S <size>] [-o format] <dev> [dev ...]\n\n"
  61                 "Options:\n"
  62                 "  -c <file>   cache file (default: /etc/blkid.tab, /dev/null = none)\n"
  63                 "  -h          print this usage message and exit\n"
  64                 "  -g          garbage collect the blkid cache\n"
  65                 "  -o <format> output format; can be one of:\n"
  66                 "              value, device, list, udev or full; (default: full)\n"
  67                 "  -s <tag>    show specified tag(s) (default show all tags)\n"
  68                 "  -t <token>  find device with a specific token (NAME=value pair)\n"
  69                 "  -l          lookup the the first device with arguments specified by -t\n"
  70                 "  -L <label>  convert LABEL to device name\n"
  71                 "  -U <uuid>   convert UUID to device name\n"
  72                 "  -v          print version and exit\n"
  73                 "  -w <file>   write cache to different file (/dev/null = no write)\n"
  74                 "  <dev>       specify device(s) to probe (default: all devices)\n\n"
  75                 "Low-level probing options:\n"
  76                 "  -p          switch to low-level mode (bypass cache)\n"
  77                 "  -S <size>   overwrite device size\n"
  78                 "  -O <offset> probe at the given offset\n"
  79                 "  -u <list>   filter by \"usage\" (e.g. -u filesystem,raid)\n"
  80                 "  -n <list>   filter by filesystem type (e.g. -n vfat,ext3)\n"
  81                 "\n",
  82                                 progname);
  83
  84         exit(error);
  85 }
  86
  87 /*
  88  * This function does "safe" printing.  It will convert non-printable
  89  * ASCII characters using '^' and M- notation.
  90  */
  91 static void safe_print(const char *cp, int len)
  92 {
  93         unsigned char   ch;
  94
  95         if (len < 0)
  96                 len = strlen(cp);
  97
  98         while (len--) {
  99                 ch = *cp++;
 100                 if (ch > 128) {
 101                         fputs("M-", stdout);
 102                         ch -= 128;
 103                 }
 104                 if ((ch < 32) || (ch == 0x7f)) {
 105                         fputc('^', stdout);
 106                         ch ^= 0x40; /* ^@, ^A, ^B; ^? for DEL */
 107                 }
 108                 fputc(ch, stdout);
 109         }
 110 }
 111
 112 static int get_terminal_width(void)
 113 {
 114 #ifdef TIOCGSIZE
 115         struct ttysize  t_win;
 116 #endif
 117 #ifdef TIOCGWINSZ
 118         struct winsize  w_win;
 119 #endif
 120         const char      *cp;
 121
 122 #ifdef TIOCGSIZE
 123         if (ioctl (0, TIOCGSIZE, &t_win) == 0)
 124                 return (t_win.ts_cols);
 125 #endif
 126 #ifdef TIOCGWINSZ
 127         if (ioctl (0, TIOCGWINSZ, &w_win) == 0)
 128                 return (w_win.ws_col);
 129 #endif
 130         cp = getenv("COLUMNS");
 131         if (cp)
 132                 return strtol(cp, NULL, 10);
 133         return 80;
 134 }
 135
 136 static int pretty_print_word(const char *str, int max_len,
 137                              int left_len, int overflow_nl)
 138 {
 139         int len = strlen(str) + left_len;
 140         int ret = 0;
 141
 142         fputs(str, stdout);
 143         if (overflow_nl && len > max_len) {
 144                 fputc('\n', stdout);
 145                 len = 0;
 146         } else if (len > max_len)
 147                 ret = len - max_len;
 148         do
 149                 fputc(' ', stdout);
 150         while (len++ < max_len);
 151         return ret;
 152 }
 153
 154 static void pretty_print_line(const char *device, const char *fs_type,
 155                               const char *label, const char *mtpt,
 156                               const char *uuid)
 157 {
 158         static int device_len = 10, fs_type_len = 7;
 159         static int label_len = 8, mtpt_len = 14;
 160         static int term_width = -1;
 161         int len, w;
 162
 163         if (term_width < 0)
 164                 term_width = get_terminal_width();
 165
 166         if (term_width > 80) {
 167                 term_width -= 80;
 168                 w = term_width / 10;
 169                 if (w > 8)
 170                         w = 8;
 171                 term_width -= 2*w;
 172                 label_len += w;
 173                 fs_type_len += w;
 174                 w = term_width/2;
 175                 device_len += w;
 176                 mtpt_len +=w;
 177         }
 178
 179         len = pretty_print_word(device, device_len, 0, 1);
 180         len = pretty_print_word(fs_type, fs_type_len, len, 0);
 181         len = pretty_print_word(label, label_len, len, 0);
 182         len = pretty_print_word(mtpt, mtpt_len, len, 0);
 183         fputs(uuid, stdout);
 184         fputc('\n', stdout);
 185 }
 186
 187 static void pretty_print_dev(blkid_dev dev)
 188 {
 189         blkid_tag_iterate       iter;
 190         const char              *type, *value, *devname;
 191         const char              *uuid = "", *fs_type = "", *label = "";
 192         int                     len, mount_flags;
 193         char                    mtpt[80];
 194         int                     retval;
 195
 196         if (dev == NULL) {
 197                 pretty_print_line("device", "fs_type", "label",
 198                                   "mount point", "UUID");
 199                 for (len=get_terminal_width()-1; len > 0; len--)
 200                         fputc('-', stdout);
 201                 fputc('\n', stdout);
 202                 return;
 203         }
 204
 205         devname = blkid_dev_devname(dev);
 206         if (access(devname, F_OK))
 207                 return;
 208
 209         /* Get the uuid, label, type */
 210         iter = blkid_tag_iterate_begin(dev);
 211         while (blkid_tag_next(iter, &type, &value) == 0) {
 212                 if (!strcmp(type, "UUID"))
 213                         uuid = value;
 214                 if (!strcmp(type, "TYPE"))
 215                         fs_type = value;
 216                 if (!strcmp(type, "LABEL"))
 217                         label = value;
 218         }
 219         blkid_tag_iterate_end(iter);
 220
 221         /* Get the mount point */
 222         mtpt[0] = 0;
 223         retval = check_mount_point(devname, &mount_flags, mtpt, sizeof(mtpt));
 224         if (retval == 0) {
 225                 if (mount_flags & MF_MOUNTED) {
 226                         if (!mtpt[0])
 227                                 strcpy(mtpt, "(mounted, mtpt unknown)");
 228                 } else if (mount_flags & MF_BUSY)
 229                         strcpy(mtpt, "(in use)");
 230                 else
 231                         strcpy(mtpt, "(not mounted)");
 232         }
 233
 234         pretty_print_line(devname, fs_type, label, mtpt, uuid);
 235 }
 236
 237 static void print_udev_format(const char *name, const char *value, size_t sz)
 238 {
 239         char enc[265], safe[256];
 240
 241         *safe = *enc = '\0';
 242
 243         if (!strcmp(name, "TYPE") || !strcmp(name, "VERSION")) {
 244                 blkid_encode_string(value, enc, sizeof(enc));
 245                 printf("ID_FS_%s=%s\n", name, enc);
 246
 247         } else if (!strcmp(name, "UUID") ||
 248                  !strcmp(name, "LABEL") ||
 249                  !strcmp(name, "UUID_SUB")) {
 250
 251                 blkid_safe_string(value, safe, sizeof(safe));
 252                 printf("ID_FS_%s=%s\n", name, safe);
 253
 254                 blkid_encode_string(value, enc, sizeof(enc));
 255                 printf("ID_FS_%s_ENC=%s\n", name, enc);
 256
 257         } else if (!strcmp(name, "PTTYPE")) {
 258                 printf("ID_PART_TABLE_TYPE=%s\n", value);
 259
 260         } else if (!strcmp(name, "PART_ENTRY_NAME") ||
 261                   !strcmp(name, "PART_ENTRY_TYPE")) {
 262
 263                 blkid_safe_string(value, safe, sizeof(safe));
 264                 printf("ID_%s=%s\n", name, safe);
 265
 266                 blkid_encode_string(value, enc, sizeof(enc));
 267                 printf("ID_%s_ENC=%s\n", name, enc);
 268
 269         } else if (!strncmp(name, "PART_ENTRY_", 11))
 270                 printf("ID_%s=%s\n", name, value);
 271
 272         else
 273                 printf("ID_FS_%s=%s\n", name, value);
 274 }
 275
 276 static int has_item(char *ary[], const char *item)
 277 {
 278         char **p;
 279
 280         for (p = ary; *p != NULL; p++)
 281                 if (!strcmp(item, *p))
 282                         return 1;
 283         return 0;
 284 }
 285
 286 static void print_value(int output, int num, const char *devname,
 287                         const char *value, const char *name, size_t valsz)
 288 {
 289         if (output & OUTPUT_VALUE_ONLY) {
 290                 fputs(value, stdout);
 291                 fputc('\n', stdout);
 292
 293         } else if (output & OUTPUT_UDEV_LIST) {
 294                 print_udev_format(name, value, valsz);
 295
 296         } else {
 297                 if (num == 1 && devname)
 298                         printf("%s: ", devname);
 299                 fputs(name, stdout);
 300                 fputs("=\"", stdout);
 301                 safe_print(value, valsz);
 302                 fputs("\" ", stdout);
 303         }
 304 }
 305
 306 static void print_tags(blkid_dev dev, char *show[], int output)
 307 {
 308         blkid_tag_iterate       iter;
 309         const char              *type, *value, *devname;
 310         int                     num = 1;
 311
 312         if (!dev)
 313                 return;
 314
 315         if (output & OUTPUT_PRETTY_LIST) {
 316                 pretty_print_dev(dev);
 317                 return;
 318         }
 319
 320         devname = blkid_dev_devname(dev);
 321
 322         if (output & OUTPUT_DEVICE_ONLY) {
 323                 printf("%s\n", devname);
 324                 return;
 325         }
 326
 327         iter = blkid_tag_iterate_begin(dev);
 328         while (blkid_tag_next(iter, &type, &value) == 0) {
 329                 if (show[0] && !has_item(show, type))
 330                         continue;
 331                 print_value(output, num++, devname, value, type, strlen(value));
 332         }
 333         blkid_tag_iterate_end(iter);
 334
 335         if (num > 1 && !(output & (OUTPUT_VALUE_ONLY | OUTPUT_UDEV_LIST)))
 336                 printf("\n");
 337 }
 338
 339
 340 static int append_str(char **res, size_t *sz, const char *a, const char *b)
 341 {
 342         char *str = *res;
 343         size_t asz = a ? strlen(a) : 0;
 344         size_t bsz = b ? strlen(b) : 0;
 345         size_t len = *sz + asz + bsz;
 346
 347         if (!len)
 348                 return -1;
 349
 350         str = realloc(str, len + 1);
 351         if (!str) {
 352                 free(*res);
 353                 return -1;
 354         }
 355         *res = str;
 356         str += *sz;
 357
 358         if (a) {
 359                 memcpy(str, a, asz);
 360                 str += asz;
 361         }
 362         if (b) {
 363                 memcpy(str, b, bsz);
 364                 str += bsz;
 365         }
 366         *str = '\0';
 367         *sz = len;
 368         return 0;
 369 }
 370
 371 /*
 372  * Compose and print ID_FS_AMBIVALENT for udev
 373  */
 374 static int print_udev_ambivalent(blkid_probe pr)
 375 {
 376         char *val = NULL;
 377         size_t valsz = 0;
 378         int count = 0, rc = -1;
 379
 380         while (!blkid_do_probe(pr)) {
 381                 const char *usage = NULL, *type = NULL, *version = NULL;
 382                 char enc[256];
 383
 384                 blkid_probe_lookup_value(pr, "USAGE", &usage, NULL);
 385                 blkid_probe_lookup_value(pr, "TYPE", &type, NULL);
 386                 blkid_probe_lookup_value(pr, "VERSION", &version, NULL);
 387
 388                 if (!usage || !type)
 389                         continue;
 390
 391                 blkid_encode_string(usage, enc, sizeof(enc));
 392                 if (append_str(&val, &valsz, enc, ":"))
 393                         goto done;
 394
 395                 blkid_encode_string(type, enc, sizeof(enc));
 396                 if (append_str(&val, &valsz, enc, version ? ":" : " "))
 397                         goto done;
 398
 399                 if (version) {
 400                         blkid_encode_string(version, enc, sizeof(enc));
 401                         if (append_str(&val, &valsz, enc, " "))
 402                                 goto done;
 403                 }
 404                 count++;
 405         }
 406
 407         if (count > 1) {
 408                 *(val + valsz - 1) = '\0';              /* rem tailing whitespace */
 409                 printf("ID_FS_AMBIVALEN=%s\n", val);
 410                 rc = 0;
 411         }
 412 done:
 413         free(val);
 414         return rc;
 415 }
 416
 417 static int lowprobe_device(blkid_probe pr, const char *devname, char *show[],
 418                         int output, blkid_loff_t offset, blkid_loff_t size)
 419 {
 420         const char *data;
 421         const char *name;
 422         int nvals = 0, n, num = 1;
 423         size_t len;
 424         int fd;
 425         int rc = 0;
 426         struct stat st;
 427         static int first = 1;
 428
 429         fd = open(devname, O_RDONLY);
 430         if (fd < 0) {
 431                 fprintf(stderr, "error: %s: %s\n", devname, strerror(errno));
 432                 return 2;
 433         }
 434         if (blkid_probe_set_device(pr, fd, offset, size))
 435                 goto done;
 436
 437         if (fstat(fd, &st))
 438                 goto done;
 439
 440         blkid_probe_enable_partitions(pr, 1);
 441         blkid_probe_set_partitions_flags(pr, BLKID_PARTS_ENTRY_DETAILS);
 442
 443         if (!S_ISCHR(st.st_mode) && blkid_probe_get_size(pr) <= 1024 * 1440) {
 444                 /*
 445                  * check if the small disk is partitioned, if yes then
 446                  * don't probe for filesystems.
 447                  */
 448                 blkid_probe_enable_superblocks(pr, 0);
 449
 450                 rc = blkid_do_fullprobe(pr);
 451                 if (rc < 0)
 452                         goto done;      /* -1 = error, 1 = nothing, 0 = succes */
 453
 454                 if (blkid_probe_lookup_value(pr, "PTTYPE", NULL, NULL) == 0)
 455                         /* partition table detected */
 456                         goto print_vals;
 457
 458                 /* small whole-disk is unpartitioned, probe for filesystems only */
 459                 blkid_probe_enable_partitions(pr, 0);
 460         }
 461
 462         blkid_probe_enable_superblocks(pr, 1);
 463
 464         rc = blkid_do_safeprobe(pr);
 465         if (rc < 0)
 466                 goto done;
 467 print_vals:
 468         nvals = blkid_probe_numof_values(pr);
 469
 470         if (nvals && !first && output & OUTPUT_UDEV_LIST)
 471                 /* add extra line between output from devices */
 472                 fputc('\n', stdout);
 473
 474         if (output & OUTPUT_DEVICE_ONLY) {
 475                 printf("%s\n", devname);
 476                 goto done;
 477         }
 478
 479         for (n = 0; n < nvals; n++) {
 480                 if (blkid_probe_get_value(pr, n, &name, &data, &len))
 481                         continue;
 482                 if (show[0] && !has_item(show, name))
 483                         continue;
 484                 len = strnlen((char *) data, len);
 485                 print_value(output, num++, devname, (char *) data, name, len);
 486         }
 487
 488         if (first)
 489                 first = 0;
 490         if (nvals >= 1 && !(output & (OUTPUT_VALUE_ONLY | OUTPUT_UDEV_LIST)))
 491                 printf("\n");
 492 done:
 493         if (rc == -2) {
 494                 if (output & OUTPUT_UDEV_LIST)
 495                         print_udev_ambivalent(pr);
 496                 else
 497                         fprintf(stderr,
 498                                 "%s: ambivalent result (probably more "
 499                                 "filesystems on the device, use wipefs(8) "
 500                                 "to see more details)\n",
 501                                 devname);
 502         }
 503         close(fd);
 504         return !nvals ? 2 : 0;
 505 }
 506
 507 /* converts comma separated list to BLKID_USAGE_* mask */
 508 static int list_to_usage(const char *list, int *flag)
 509 {
 510         int mask = 0;
 511         const char *word = NULL, *p = list;
 512
 513         if (p && strncmp(p, "no", 2) == 0) {
 514                 *flag = BLKID_FLTR_NOTIN;
 515                 p += 2;
 516         }
 517         if (!p || !*p)
 518                 goto err;
 519         while(p) {
 520                 word = p;
 521                 p = strchr(p, ',');
 522                 if (p)
 523                         p++;
 524                 if (!strncmp(word, "filesystem", 10))
 525                         mask |= BLKID_USAGE_FILESYSTEM;
 526                 else if (!strncmp(word, "raid", 4))
 527                         mask |= BLKID_USAGE_RAID;
 528                 else if (!strncmp(word, "crypto", 6))
 529                         mask |= BLKID_USAGE_CRYPTO;
 530                 else if (!strncmp(word, "other", 5))
 531                         mask |= BLKID_USAGE_OTHER;
 532                 else
 533                         goto err;
 534         }
 535         return mask;
 536 err:
 537         *flag = 0;
 538         fprintf(stderr, "unknown kerword in -u <list> argument: '%s'\n",
 539                         word ? word : list);
 540         exit(4);
 541 }
 542
 543 /* converts comma separated list to types[] */
 544 static char **list_to_types(const char *list, int *flag)
 545 {
 546         int i;
 547         const char *p = list;
 548         char **res;
 549
 550         if (p && strncmp(p, "no", 2) == 0) {
 551                 *flag = BLKID_FLTR_NOTIN;
 552                 p += 2;
 553         }
 554         if (!p || !*p) {
 555                 fprintf(stderr, "error: -u <list> argument is empty\n");
 556                 goto err;
 557         }
 558         for (i = 1; p && (p = strchr(p, ',')); i++, p++);
 559
 560         res = calloc(i + 1, sizeof(char *));
 561         if (!res)
 562                 goto err_mem;
 563         p = *flag & BLKID_FLTR_NOTIN ? list + 2 : list;
 564         i = 0;
 565
 566         while(p) {
 567                 const char *word = p;
 568                 p = strchr(p, ',');
 569                 res[i] = p ? strndup(word, p - word) : strdup(word);
 570                 if (!res[i++])
 571                         goto err_mem;
 572                 if (p)
 573                         p++;
 574         }
 575         res[i] = NULL;
 576         return res;
 577 err_mem:
 578         fprintf(stderr, "out of memory\n");
 579 err:
 580         *flag = 0;
 581         free(res);
 582         exit(4);
 583 }
 584
 585 static void free_types_list(char *list[])
 586 {
 587         char **n;
 588
 589         if (!list)
 590                 return;
 591         for (n = list; *n; n++)
 592                 free(*n);
 593         free(list);
 594 }
 595
 596 int main(int argc, char **argv)
 597 {
 598         blkid_cache cache = NULL;
 599         char *devices[128] = { NULL, };
 600         char *show[128] = { NULL, };
 601         char *search_type = NULL, *search_value = NULL;
 602         char *read = NULL;
 603         char *write = NULL;
 604         int fltr_usage = 0;
 605         char **fltr_type = NULL;
 606         int fltr_flag = BLKID_FLTR_ONLYIN;
 607         unsigned int numdev = 0, numtag = 0;
 608         int version = 0;
 609         int err = 4;
 610         unsigned int i;
 611         int output_format = 0;
 612         int lookup = 0, gc = 0, lowprobe = 0, eval = 0;
 613         int c;
 614         uintmax_t offset = 0, size = 0;
 615
 616         show[0] = NULL;
 617
 618         while ((c = getopt (argc, argv, "c:f:ghlL:n:o:O:ps:S:t:u:U:w:v")) != EOF)
 619                 switch (c) {
 620                 case 'c':
 621                         if (optarg && !*optarg)
 622                                 read = NULL;
 623                         else
 624                                 read = optarg;
 625                         if (!write)
 626                                 write = read;
 627                         break;
 628                 case 'L':
 629                         eval++;
 630                         search_value = strdup(optarg);
 631                         search_type = strdup("LABEL");
 632                         break;
 633                 case 'n':
 634                         if (fltr_usage) {
 635                                 fprintf(stderr, "error: -u and -n options are mutually exclusive\n");
 636                                 exit(4);
 637                         }
 638                         fltr_type = list_to_types(optarg, &fltr_flag);
 639                         break;
 640                 case 'u':
 641                         if (fltr_type) {
 642                                 fprintf(stderr, "error: -u and -n options are mutually exclusive\n");
 643                                 exit(4);
 644                         }
 645                         fltr_usage = list_to_usage(optarg, &fltr_flag);
 646                         break;
 647                 case 'U':
 648                         eval++;
 649                         search_value = strdup(optarg);
 650                         search_type = strdup("UUID");
 651                         break;
 652                 case 'l':
 653                         lookup++;
 654                         break;
 655                 case 'g':
 656                         gc = 1;
 657                         break;
 658                 case 'o':
 659                         if (!strcmp(optarg, "value"))
 660                                 output_format = OUTPUT_VALUE_ONLY;
 661                         else if (!strcmp(optarg, "device"))
 662                                 output_format = OUTPUT_DEVICE_ONLY;
 663                         else if (!strcmp(optarg, "list"))
 664                                 output_format = OUTPUT_PRETTY_LIST;
 665                         else if (!strcmp(optarg, "udev"))
 666                                 output_format = OUTPUT_UDEV_LIST;
 667                         else if (!strcmp(optarg, "full"))
 668                                 output_format = 0;
 669                         else {
 670                                 fprintf(stderr, "Invalid output format %s. "
 671                                         "Choose from value,\n\t"
 672                                         "device, list, udev or full\n", optarg);
 673                                 exit(4);
 674                         }
 675                         break;
 676                 case 'O':
 677                         if (strtosize(optarg, &offset))
 678                                 fprintf(stderr,
 679                                         "Invalid offset '%s' specified\n",
 680                                         optarg);
 681                         break;
 682                 case 'p':
 683                         lowprobe++;
 684                         break;
 685                 case 's':
 686                         if (numtag + 1 >= sizeof(show) / sizeof(*show)) {
 687                                 fprintf(stderr, "Too many tags specified\n");
 688                                 usage(err);
 689                         }
 690                         show[numtag++] = optarg;
 691                         show[numtag] = NULL;
 692                         break;
 693                 case 'S':
 694                         if (strtosize(optarg, &size))
 695                                 fprintf(stderr,
 696                                         "Invalid size '%s' specified\n",
 697                                         optarg);
 698                         break;
 699                 case 't':
 700                         if (search_type) {
 701                                 fprintf(stderr, "Can only search for "
 702                                                 "one NAME=value pair\n");
 703                                 usage(err);
 704                         }
 705                         if (blkid_parse_tag_string(optarg,
 706                                                    &search_type,
 707                                                    &search_value)) {
 708                                 fprintf(stderr, "-t needs NAME=value pair\n");
 709                                 usage(err);
 710                         }
 711                         break;
 712                 case 'v':
 713                         version = 1;
 714                         break;
 715                 case 'w':
 716                         if (optarg && !*optarg)
 717                                 write = NULL;
 718                         else
 719                                 write = optarg;
 720                         break;
 721                 case 'h':
 722                         err = 0;
 723                 default:
 724                         usage(err);
 725                 }
 726
 727         while (optind < argc)
 728                 devices[numdev++] = argv[optind++];
 729
 730         if (version) {
 731                 print_version(stdout);
 732                 goto exit;
 733         }
 734
 735         /* convert LABEL/UUID lookup to evaluate request */
 736         if (lookup && output_format == OUTPUT_DEVICE_ONLY && search_type &&
 737             (!strcmp(search_type, "LABEL") || !strcmp(search_type, "UUID"))) {
 738                 eval++;
 739                 lookup = 0;
 740         }
 741
 742         if (!lowprobe && !eval && blkid_get_cache(&cache, read) < 0)
 743                 goto exit;
 744
 745         if (gc) {
 746                 blkid_gc_cache(cache);
 747                 err = 0;
 748                 goto exit;
 749         }
 750         err = 2;
 751
 752         if (eval == 0 && output_format & OUTPUT_PRETTY_LIST) {
 753                 if (lowprobe) {
 754                         fprintf(stderr, "The low-level probing mode does not "
 755                                         "support 'list' output format\n");
 756                         exit(4);
 757                 }
 758                 pretty_print_dev(NULL);
 759         }
 760
 761         if (lowprobe) {
 762                 /*
 763                  * Low-level API
 764                  */
 765                 blkid_probe pr;
 766
 767                 if (!numdev) {
 768                         fprintf(stderr, "The low-level probing mode "
 769                                         "requires a device\n");
 770                         exit(4);
 771                 }
 772                 pr = blkid_new_probe();
 773                 if (!pr)
 774                         goto exit;
 775
 776                 blkid_probe_set_superblocks_flags(pr,
 777                                 BLKID_SUBLKS_LABEL | BLKID_SUBLKS_UUID |
 778                                 BLKID_SUBLKS_TYPE | BLKID_SUBLKS_SECTYPE |
 779                                 BLKID_SUBLKS_USAGE | BLKID_SUBLKS_VERSION);
 780
 781                 if (fltr_usage &&
 782                     blkid_probe_filter_superblocks_usage(pr, fltr_flag, fltr_usage))
 783                         goto exit;
 784                 else if (fltr_type &&
 785                     blkid_probe_filter_superblocks_type(pr, fltr_flag, fltr_type))
 786                         goto exit;
 787
 788                 for (i = 0; i < numdev; i++)
 789                         err = lowprobe_device(pr, devices[i], show,
 790                                         output_format,
 791                                         (blkid_loff_t) offset,
 792                                         (blkid_loff_t) size);
 793                 blkid_free_probe(pr);
 794         } else if (eval) {
 795                 /*
 796                  * Evaluate API
 797                  */
 798                 char *res = blkid_evaluate_tag(search_type, search_value, NULL);
 799                 if (res) {
 800                         err = 0;
 801                         printf("%s\n", res);
 802                 }
 803         } else if (lookup) {
 804                 /*
 805                  * Classic (cache based) API
 806                  */
 807                 blkid_dev dev;
 808
 809                 if (!search_type) {
 810                         fprintf(stderr, "The lookup option requires a "
 811                                 "search type specified using -t\n");
 812                         exit(4);
 813                 }
 814                 /* Load any additional devices not in the cache */
 815                 for (i = 0; i < numdev; i++)
 816                         blkid_get_dev(cache, devices[i], BLKID_DEV_NORMAL);
 817
 818                 if ((dev = blkid_find_dev_with_tag(cache, search_type,
 819                                                    search_value))) {
 820                         print_tags(dev, show, output_format);
 821                         err = 0;
 822                 }
 823         /* If we didn't specify a single device, show all available devices */
 824         } else if (!numdev) {
 825                 blkid_dev_iterate       iter;
 826                 blkid_dev               dev;
 827
 828                 blkid_probe_all(cache);
 829
 830                 iter = blkid_dev_iterate_begin(cache);
 831                 blkid_dev_set_search(iter, search_type, search_value);
 832                 while (blkid_dev_next(iter, &dev) == 0) {
 833                         dev = blkid_verify(cache, dev);
 834                         if (!dev)
 835                                 continue;
 836                         print_tags(dev, show, output_format);
 837                         err = 0;
 838                 }
 839                 blkid_dev_iterate_end(iter);
 840         /* Add all specified devices to cache (optionally display tags) */
 841         } else for (i = 0; i < numdev; i++) {
 842                 blkid_dev dev = blkid_get_dev(cache, devices[i],
 843                                                   BLKID_DEV_NORMAL);
 844
 845                 if (dev) {
 846                         if (search_type &&
 847                             !blkid_dev_has_tag(dev, search_type,
 848                                                search_value))
 849                                 continue;
 850                         print_tags(dev, show, output_format);
 851                         err = 0;
 852                 }
 853         }
 854
 855 exit:
 856         free(search_type);
 857         free(search_value);
 858         free_types_list(fltr_type);
 859         if (!lowprobe && !eval)
 860                 blkid_put_cache(cache);
 861         return err;
 862 }