diff options
Diffstat (limited to 'gnu/build/file-systems.scm')
| -rw-r--r-- | gnu/build/file-systems.scm | 88 |
1 files changed, 67 insertions, 21 deletions
diff --git a/gnu/build/file-systems.scm b/gnu/build/file-systems.scm index fe98df95d5..47aa77dd3e 100644 --- a/gnu/build/file-systems.scm +++ b/gnu/build/file-systems.scm @@ -1,6 +1,7 @@ ;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2014, 2015, 2016, 2017 Ludovic Courtès <ludo@gnu.org> ;;; Copyright © 2016, 2017 David Craven <david@craven.ch> +;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com> ;;; ;;; This file is part of GNU Guix. ;;; @@ -47,12 +48,7 @@ mount-flags->bit-mask check-file-system - mount-file-system) - #:re-export (mount - umount - MS_BIND - MS_MOVE - MS_RDONLY)) + mount-file-system)) ;;; Commentary: ;;; @@ -61,13 +57,6 @@ ;;; ;;; Code: -;; 'mount' is already defined in the statically linked Guile used for initial -;; RAM disks, in which case the bindings in (guix build syscalls) do not work -;; (the FFI bindings do not work there). Override them in that case. -(when (module-defined? the-scm-module 'mount) - (set! mount (@ (guile) mount)) - (set! umount (@ (guile) umount))) - (define (bind-mount source target) "Bind-mount SOURCE at TARGET." (mount source target "" MS_BIND)) @@ -241,6 +230,63 @@ Trailing spaces are trimmed." ;;; +;;; ISO9660 file systems. +;;; + +;; <http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-119.pdf>. + +(define (iso9660-superblock? sblock) + "Return #t when SBLOCK is a iso9660 superblock." + (bytevector=? (sub-bytevector sblock 1 6) + ;; Note: "\x01" is the volume descriptor format version + (string->utf8 "CD001\x01"))) + +(define (read-iso9660-primary-volume-descriptor device offset) + "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))) + (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." + ;; 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." + ;; 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". + ;; Compare /dev/disk/by-uuid entry: "2014-12-02-19-30-23-00". + (sub-bytevector sblock 830 16)) + +(define (iso9660-uuid->string uuid) + "Given an UUID bytevector, return its timestamp string." + (define (digits->string bytes) + (latin1->string bytes (lambda (c) #f))) + (let* ((year (sub-bytevector uuid 0 4)) + (month (sub-bytevector uuid 4 2)) + (day (sub-bytevector uuid 6 2)) + (hour (sub-bytevector uuid 8 2)) + (minute (sub-bytevector uuid 10 2)) + (second (sub-bytevector uuid 12 2)) + (hundredths (sub-bytevector uuid 14 2)) + (parts (list year month day hour minute second hundredths))) + (string-append (string-join (map digits->string parts))))) + +(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." + (string-trim-right (latin1->string (sub-bytevector sblock 40 32) + (lambda (c) #f)) #\space)) + + +;;; ;;; LUKS encrypted devices. ;;; @@ -351,7 +397,9 @@ partition field reader that returned a value." (_ #f))) (define %partition-label-readers - (list (partition-field-reader read-ext2-superblock + (list (partition-field-reader read-iso9660-superblock + iso9660-superblock-volume-name) + (partition-field-reader read-ext2-superblock ext2-superblock-volume-name) (partition-field-reader read-btrfs-superblock btrfs-superblock-volume-name) @@ -359,7 +407,9 @@ partition field reader that returned a value." fat32-superblock-volume-name))) (define %partition-uuid-readers - (list (partition-field-reader read-ext2-superblock + (list (partition-field-reader read-iso9660-superblock + iso9660-superblock-uuid) + (partition-field-reader read-ext2-superblock ext2-superblock-uuid) (partition-field-reader read-btrfs-superblock btrfs-superblock-uuid) @@ -576,10 +626,6 @@ corresponds to the symbols listed in FLAGS." (() 0)))) -(define (regular-file? file-name) - "Return #t if FILE-NAME is a regular file." - (eq? (stat:type (stat file-name)) 'regular)) - (define* (mount-file-system spec #:key (root "/root")) "Mount the file system described by SPEC under ROOT. SPEC must have the form: @@ -619,9 +665,9 @@ run a file system check." (check-file-system source type)) ;; Create the mount point. Most of the time this is a directory, but - ;; in the case of a bind mount, a regular file may be needed. + ;; in the case of a bind mount, a regular file or socket may be needed. (if (and (= MS_BIND (logand flags MS_BIND)) - (regular-file? source)) + (not (file-is-directory? source))) (unless (file-exists? mount-point) (mkdir-p (dirname mount-point)) (call-with-output-file mount-point (const #t))) |