diff options
Diffstat (limited to 'gnu/system/file-systems.scm')
| -rw-r--r-- | gnu/system/file-systems.scm | 38 |
1 files changed, 33 insertions, 5 deletions
diff --git a/gnu/system/file-systems.scm b/gnu/system/file-systems.scm index 4cc1221eb8..fa56853fd1 100644 --- a/gnu/system/file-systems.scm +++ b/gnu/system/file-systems.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2013, 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2013, 2014, 2015, 2016, 2017 Ludovic Courtès <ludo@gnu.org> ;;; ;;; This file is part of GNU Guix. ;;; @@ -95,11 +95,39 @@ (dependencies file-system-dependencies ; list of <file-system> (default '()))) ; or <mapped-device> -(define-inlinable (file-system-needed-for-boot? fs) - "Return true if FS has the 'needed-for-boot?' flag set, or if it's the root -file system." +(define %not-slash + (char-set-complement (char-set #\/))) + +(define (file-prefix? file1 file2) + "Return #t if FILE1 denotes the name of a file that is a parent of FILE2, +where both FILE1 and FILE2 are absolute file name. For example: + + (file-prefix? \"/gnu\" \"/gnu/store\") + => #t + + (file-prefix? \"/gn\" \"/gnu/store\") + => #f +" + (and (string-prefix? "/" file1) + (string-prefix? "/" file2) + (let loop ((file1 (string-tokenize file1 %not-slash)) + (file2 (string-tokenize file2 %not-slash))) + (match file1 + (() + #t) + ((head1 tail1 ...) + (match file2 + ((head2 tail2 ...) + (and (string=? head1 head2) (loop tail1 tail2))) + (() + #f))))))) + +(define (file-system-needed-for-boot? fs) + "Return true if FS has the 'needed-for-boot?' flag set, or if it holds the +store--e.g., if FS is the root file system." (or (%file-system-needed-for-boot? fs) - (string=? "/" (file-system-mount-point fs)))) + (and (file-prefix? (file-system-mount-point fs) (%store-prefix)) + (not (memq 'bind-mount (file-system-flags fs)))))) (define (file-system->spec fs) "Return a list corresponding to file-system FS that can be passed to the |