file-systems: Support UUIDs for FAT12.

* gnu/build/file-systems.scm (fat16-superblock?): Support FAT12.

Change-Id: Ia14899134e02bda54b0796efb0bc1c6f89e95c0d
Signed-off-by: Danny Milosavljevic <dannym@friendly-machines.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/gnu/build/file-systems.scm b/gnu/build/file-systems.scm
index 6fd9f950939..c506a4911ff 100644
--- a/gnu/build/file-systems.scm
+++ b/gnu/build/file-systems.scm
@@ -608,13 +608,16 @@ using the least destructive approach."
 
 
 ;;;
-;;; FAT16 file systems.
+;;; FAT16/FAT12 file systems.
 ;;;
 
 (define (fat16-superblock? sblock)
-  "Return #t when SBLOCK is a fat16 boot record."
-  (bytevector=? (sub-bytevector sblock 54 8)
-                (string->utf8 "FAT16   ")))
+  "Return #t when SBLOCK is a fat16 or fat12 boot record."
+  (let ((boot-record (sub-bytevector sblock 54 8)))
+    (or (bytevector=? boot-record
+                      (string->utf8 "FAT16   "))
+        (bytevector=? boot-record
+                      (string->utf8 "FAT12   ")))))
 
 (define (read-fat16-superblock device)
   "Return the raw contents of DEVICE's fat16 superblock as a bytevector, or