LXR toybox/toys/other/blkid.c

   1/* blkid.c - Prints type, label and UUID of filesystem(s).
   2 *
   3 * Copyright 2013 Brad Conroy <bconroy@uis.edu>
   4 *
   5 * See ftp://ftp.kernel.org/pub/linux/utils/util-linux/v2.24/libblkid-docs/api-index-full.html
   6
   7USE_BLKID(NEWTOY(blkid, 0, TOYFLAG_BIN))
   8USE_FSTYPE(NEWTOY(fstype, "<1", TOYFLAG_BIN))
   9
  10config BLKID
  11  bool "blkid"
  12  default y
  13  help
  14    usage: blkid DEV...
  15
  16    Prints type, label and UUID of filesystem on a block device or image.
  17
  18config FSTYPE
  19  bool "fstype"
  20  default y
  21  help
  22    usage: fstype DEV...
  23
  24    Prints type of filesystem on a block device or image.
  25*/
  26
  27#define FOR_blkid
  28#include "toys.h"
  29
  30struct fstype {
  31  char *name;
  32  uint64_t magic;
  33  int magic_len, magic_offset, uuid_off, label_len, label_off;
  34};
  35
  36static const struct fstype fstypes[] = {
  37  {"ext2", 0xEF53, 2, 1080, 1128, 16, 1144}, // keep this first for ext3/4 check
  38  {"swap", 0x4341505350415753LL, 8, 4086, 1036, 15, 1052},
  39  // NTFS label actually 8/16 0x4d80 but horrible: 16 bit wide characters via
  40  // codepage, something called a uuid that's only 8 bytes long...
  41  {"ntfs", 0x5346544e, 4, 3, 0x48+(8<<24), 0, 0},
  42
  43  {"adfs", 0xadf5, 2, 0xc00, 0,0,0},
  44  {"bfs", 0x1badface, 4, 0, 0,0,0},
  45  {"btrfs", 0x4D5F53665248425FULL, 8, 65600, 65803, 256, 65819},
  46  {"cramfs", 0x28cd3d45, 4, 0, 0, 16, 48},
  47  {"f2fs", 0xF2F52010, 4, 1024, 1132, 16, 1110},
  48  {"jfs", 0x3153464a, 4, 32768, 32920, 16, 32904},
  49  {"nilfs", 0x3434, 2, 1030, 1176, 80, 1192},
  50  {"reiserfs", 0x724573496552ULL, 6, 8244, 8276, 16, 8292},
  51  {"reiserfs", 0x724573496552ULL, 6, 65588, 65620, 16, 65636},
  52  {"romfs", 0x2d6d6f72, 4, 0, 0,0,0},
  53  {"squashfs", 0x73717368, 4, 0, 0,0,0},
  54  {"xiafs", 0x012fd16d, 4, 572, 0,0,0},
  55  {"xfs", 0x42534658, 4, 0, 32, 12, 108},
  56  {"vfat", 0x3233544146ULL, 5, 82, 67+(4<<24), 11, 71},  // fat32
  57  {"vfat", 0x31544146, 4, 54, 39+(4<<24), 11, 43}     // fat1
  58};
  59
  60static void do_blkid(int fd, char *name)
  61{
  62  int off, i, j, len;
  63  char *type;
  64
  65  off = i = 0;
  66
  67  for (;;) {
  68    int pass = 0;
  69
  70    // Read next block of data
  71    len = readall(fd, toybuf, sizeof(toybuf));
  72    if (len != sizeof(toybuf)) return;
  73
  74    // Iterate through types in range
  75    for (i=0; i < sizeof(fstypes)/sizeof(struct fstype); i++) {
  76      uint64_t test;
  77
  78      // Skip tests not in this 4k block
  79      if (fstypes[i].magic_offset > off+sizeof(toybuf)) {
  80        pass++;
  81        continue;
  82      }
  83      if (fstypes[i].magic_offset < off) continue;
  84
  85      // Populate 64 bit little endian magic value
  86      test = 0;
  87      for (j = 0; j < fstypes[i].magic_len; j++)
  88        test += ((uint64_t)toybuf[j+fstypes[i].magic_offset-off])<<(8*j);
  89      if (test == fstypes[i].magic) break;
  90    }
  91
  92    if (i == ARRAY_LEN(fstypes)) {
  93      off += len;
  94      if (pass) continue;
  95      return;
  96    }
  97    break;
  98  }
  99
 100  // distinguish ext2/3/4
 101  type = fstypes[i].name;
 102  if (!i) {
 103    if (toybuf[1116]&4) type = "ext3";
 104    if (toybuf[1120]&64) type = "ext4";
 105  }
 106
 107  // Could special case NTFS here...
 108
 109  // Output for fstype
 110  if (*toys.which->name == 'f') {
 111    puts(type);
 112    return;
 113  }
 114
 115  // output for blkid
 116  printf("%s:",name);
 117
 118  if (fstypes[i].label_len) {
 119    char *s = toybuf+fstypes[i].label_off-off;
 120
 121    len = fstypes[i].label_len;
 122    if (!strcmp(type, "vfat")) {
 123      while (len && s[len-1]==' ') len--;
 124      if (strstart(&s, "NO NAME")) len=0;
 125    }
 126    if (len && *s) printf(" LABEL=\"%.*s\"", len, s);
 127  }
 128
 129  if (fstypes[i].uuid_off) {
 130    int bits = 0x550, size = fstypes[i].uuid_off >> 24,
 131        uoff = (fstypes[i].uuid_off & ((1<<24)-1))-off;
 132
 133    if (size) bits = 4*(size == 4);
 134    else size = 16;
 135
 136    printf(" UUID=\"");
 137    for (j = 0; j < size; j++) printf("-%02x"+!(bits & (1<<j)), toybuf[uoff+j]);
 138    printf("\"");
 139  }
 140
 141  printf(" TYPE=\"%s\"\n", type);
 142}
 143
 144void blkid_main(void)
 145{
 146  if (*toys.optargs) loopfiles(toys.optargs, do_blkid);
 147  else {
 148    unsigned int ma, mi, sz, fd;
 149    char *name = toybuf, *buffer = toybuf+1024, device[32];
 150    FILE *fp = xfopen("/proc/partitions", "r");
 151
 152    while (fgets(buffer, 1024, fp)) {
 153      *name = 0;
 154      if (sscanf(buffer, " %u %u %u %[^\n ]", &ma, &mi, &sz, name) != 4)
 155        continue;
 156
 157      sprintf(device, "/dev/%.20s", name);
 158      if (-1 == (fd = open(device, O_RDONLY))) {
 159        if (errno != ENOMEDIUM) perror_msg_raw(device);
 160      } else {
 161        do_blkid(fd, device);
 162        close(fd);
 163      }
 164    }
 165    if (CFG_TOYBOX_FREE) fclose(fp);
 166  }
 167}
 168
 169void fstype_main(void)
 170{
 171  loopfiles(toys.optargs, do_blkid);
 172}
 173