diff options
Diffstat (limited to 'gnu/build/file-systems.scm')
| -rw-r--r-- | gnu/build/file-systems.scm | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/gnu/build/file-systems.scm b/gnu/build/file-systems.scm index 47aa77dd3e..3e0873377a 100644 --- a/gnu/build/file-systems.scm +++ b/gnu/build/file-systems.scm @@ -236,7 +236,7 @@ Trailing spaces are trimmed." ;; <http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-119.pdf>. (define (iso9660-superblock? sblock) - "Return #t when SBLOCK is a iso9660 superblock." + "Return #t when SBLOCK is an iso9660 volume descriptor." (bytevector=? (sub-bytevector sblock 1 6) ;; Note: "\x01" is the volume descriptor format version (string->utf8 "CD001\x01"))) @@ -245,20 +245,26 @@ Trailing spaces are trimmed." "Find and read the first primary volume descriptor, starting at OFFSET. Return #f if not found." (let* ((sblock (read-superblock device offset 2048 iso9660-superblock?)) - (type-code (if sblock (array-ref sblock 0) 255))) + (type-code (if sblock + (bytevector-u8-ref sblock 0) + (error (format #f + "Could not read ISO9660 primary +volume descriptor from ~s" + device))))) (match type-code (255 #f) ; Volume Descriptor Set Terminator. (1 sblock) ; Primary Volume Descriptor (_ (read-iso9660-primary-volume-descriptor device (+ offset 2048)))))) (define (read-iso9660-superblock device) - "Return the raw contents of DEVICE's iso9660 superblock as a bytevector, or -#f if DEVICE does not contain a iso9660 file system." + "Return the raw contents of DEVICE's iso9660 primary volume descriptor +as a bytevector, or #f if DEVICE does not contain an iso9660 file system." ;; Start reading at sector 16. (read-iso9660-primary-volume-descriptor device (* 2048 16))) (define (iso9660-superblock-uuid sblock) - "Return the modification time of a iso9660 superblock SBLOCK as a bytevector." + "Return the modification time of an iso9660 primary volume descriptor +SBLOCK as a bytevector." ;; Drops GMT offset for compatibility with Grub, blkid and /dev/disk/by-uuid. ;; Compare Grub: "2014-12-02-19-30-23-00". ;; Compare blkid result: "2014-12-02-19-30-23-00". @@ -282,6 +288,7 @@ Trailing spaces are trimmed." (define (iso9660-superblock-volume-name sblock) "Return the volume name of SBLOCK as a string. The volume name is an ASCII string. Trailing spaces are trimmed." + ;; Note: Valid characters are of the set "[0-9][A-Z]_" (ECMA-119 Appendix A) (string-trim-right (latin1->string (sub-bytevector sblock 40 32) (lambda (c) #f)) #\space)) |