From mboxrd@z Thu Jan 1 00:00:00 1970 From: Danny Milosavljevic Subject: Re: GuixSD bootable ISO-9669 image (was: Re: GuixSD on servers [Fwd: [rtracker.1984.is #131647] A question about VServer system specific requirements]) Date: Thu, 27 Apr 2017 22:00:09 +0200 Message-ID: <20170427220009.1d0d4607@scratchpost.org> References: <20170418141719.llp77itz7vyq5rij@abyayala> <87k26hwxt0.fsf@gmail.com> <8760i0m7vg.fsf@gnu.org> <87pog3u3ms.fsf@gmail.com> <87k26afl07.fsf_-_@gmail.com> <20170427190840.79bcaa76@scratchpost.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:44509) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d3paP-00011T-F8 for guix-devel@gnu.org; Thu, 27 Apr 2017 16:00:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d3paK-0004d1-JC for guix-devel@gnu.org; Thu, 27 Apr 2017 16:00:21 -0400 Received: from dd1012.kasserver.com ([85.13.128.8]:40954) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d3paK-0004cc-CA for guix-devel@gnu.org; Thu, 27 Apr 2017 16:00:16 -0400 In-Reply-To: <20170427190840.79bcaa76@scratchpost.org> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Chris Marusich Cc: guix-devel@gnu.org Something like this (totally untested): diff --git a/gnu/build/file-systems.scm b/gnu/build/file-systems.scm index 0cb84b8aa..be512d59c 100644 --- a/gnu/build/file-systems.scm +++ b/gnu/build/file-systems.scm @@ -230,6 +230,55 @@ Trailing spaces are trimmed." ^L ;;; +;;; ISO9660 file systems. +;;; + +;; . + +;(define-syntax %iso9660-endianness +; ;; Endianness of iso9660 file systems that we use. +; ;; Actually, iso9660 has redundant data (i.e. data for both endiannesses). +; (identifier-syntax (endianness little))) + +(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 (array-ref sblock 0))) ; FIXME if sblock + (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 Volume ID of a iso9660 superblock SBLOCK as a 4-byte bytevector." + ;; Note: The field is the volume creation time. + ;; FIXME Use only certain parts (See grub). + ;; FIXME treat "all 0" as invalid. + (sub-bytevector sblock 813 17)) + +;; FIXME make result human-readable (See grub). +;(define (iso9660-uuid->string uuid) + +(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)) + +^L +;;; ;;; LUKS encrypted devices. ;;; @@ -340,7 +389,9 @@ 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) @@ -348,7 +399,9 @@ 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)