1 files changed, 132 insertions, 0 deletions
diff --git a/toys/other/blkid.c b/toys/other/blkid.c
new file mode 100644
index 00000000..99d6999a
--- /dev/null
+++ b/toys/other/blkid.c
@@ -0,0 +1,132 @@
+/* blkid.c - Prints type, label and UUID of filesystem(s).
+ *
+ * Copyright 2013 Brad Conroy <bconroy@uis.edu>
+ *
+ * See ftp://ftp.kernel.org/pub/linux/utils/util-linux/v2.24/libblkid-docs/api-index-full.html
+
+USE_BLKID(NEWTOY(blkid, "<1", TOYFLAG_BIN))
+USE_BLKID(OLDTOY(fstype, blkid, "<1", TOYFLAG_BIN))
+
+config BLKID
+  bool "blkid"
+  default y
+  help
+    usage: blkid [block device...]
+    Prints type, label and UUID of filesystem.
+*/
+
+#define FOR_blkid
+#include "toys.h"
+
+struct fstype {
+  char *name;
+  uint64_t magic;
+  int magic_len, magic_offset, uuid_off, label_len, label_off;
+};
+
+static const struct fstype fstypes[] = {
+  // ext3 = buf[1116]&4 ext4 = buf[1120]&64
+  {"ext2", 0xEF53, 2, 1080, 1128, 16, 1144},
+  // label actually 8/16 0x4d80 but horrible: 16 bit wide characters via
+  // codepage, something called a uuid that's only 8 bytes long...
+  {"ntfs", 0x5346544e, 4, 3, 0x48+(8<<24), 0, 0},
+
+  {"adfs", 0xadf5, 2, 0xc00, 0,0,0},
+  {"bfs", 0x1badface, 4, 0, 0,0,0},
+  {"btrfs", 0x4D5F53665248425FULL, 8, 65600, 65803, 256, 65819},
+  {"cramfs", 0x28cd3d45, 4, 0, 0, 16, 48},
+  {"f2fs", 0xF2F52010, 4, 1024, 1132, 16, 1110},
+  {"jfs", 0x3153464a, 4, 32768, 32920, 16, 32904},
+  {"nilfs", 0x3434, 2, 1030, 1176, 80, 1192},
+  {"murderfs", 0x724573496552, 6, 8244, 8276, 16, 8292},
+  {"murderfs", 0x724573496552, 6, 65588, 65620, 16, 65536},
+  {"romfs", 0x2d6d6f72, 4, 0, 0,0,0},
+  {"squashfs", 0x73717368, 4, 0, 0,0,0},
+  {"xiafs", 0x012fd16d, 4, 572, 0,0,0},
+  {"xfs", 0x42534658, 4, 0, 32, 12, 108},
+  {"vfat", 0x3233544146, 5, 82, 67+(4<<24), 11, 71},  // fat32
+  {"vfat", 0x31544146, 4, 54, 39+(4<<24), 11, 43}     // fat1
+};
+
+/* TODO if no args use proc/partitions */
+void do_blkid(int fd, char *name)
+{
+  int off, i, j;
+  char *type;
+
+  off = i = 0;
+
+  for (;;) {
+    int pass = 0, len;
+
+    // Read next block of data
+    len = readall(fd, toybuf, sizeof(toybuf));
+    if (len != sizeof(toybuf)) return;
+
+    // Iterate through types in range
+    for (i=0; i < sizeof(fstypes)/sizeof(struct fstype); i++) {
+      uint64_t test;
+
+      // Skip tests not in this 4k block
+      if (fstypes[i].magic_offset > off+sizeof(toybuf)) {
+        pass++;
+        continue;
+      }
+      if (fstypes[i].magic_offset < off) continue;
+
+      // Populate 64 bit little endian magic value
+      test = 0;
+      for (j = 0; j < fstypes[i].magic_len; j++)
+        test += ((uint64_t)toybuf[j+fstypes[i].magic_offset-off])<<(8*j);
+      if (test == fstypes[i].magic) break;
+    }
+
+    if (i == sizeof(fstypes)/sizeof(struct fstype)) {
+      off += len;
+      if (pass) continue;
+      return;
+    }
+    break;
+  }
+
+  // distinguish ext2/3/4
+  type = fstypes[i].name;
+  if (!i) {
+    if (toybuf[1116]&4) type = "ext3";
+    if (toybuf[1120]&64) type = "ext4";
+  }
+
+  // Could special case NTFS here...
+
+  // Output for fstype
+  if (*toys.which->name == 'f') {
+    puts(type);
+    return;
+  }
+
+  // output for blkid
+  printf("%s:",name);
+
+  if (fstypes[i].label_len)
+    printf(" LABEL=\"%.*s\"", fstypes[i].label_len,
+           toybuf+fstypes[i].label_off-off);
+
+  if (fstypes[i].uuid_off) {
+    int bits = 0x550, size = fstypes[i].uuid_off >> 24,
+        uoff = (fstypes[i].uuid_off & ((1<<24)-1))-off;
+
+    if (size) bits = 4*(size == 4);
+    else size = 16;
+
+    printf(" UUID=\"");
+    for (j = 0; j < size; j++) printf("-%02x"+!(bits & (1<<j)), toybuf[uoff+j]);
+    printf("\"");
+  }
+
+  printf(" TYPE=\"%s\"\n", fstypes[i].name);
+}
+
+void blkid_main(void)
+{
+  loopfiles(toys.optargs, do_blkid);
+}