activation: Factorize the link-or-copy trick.

* gnu/build/activation.scm (link-or-copy): New procedure.
  (activate-setuid-programs): Use it.
This commit is contained in:
Ludovic Courtès 2014-09-11 21:25:58 +02:00
parent f489668723
commit 095f4deb4b
1 changed files with 12 additions and 7 deletions

View File

@ -175,19 +175,24 @@ numeric gid or #f."
;; Place where setuid programs are stored.
"/run/setuid-programs")
(define (link-or-copy source target)
"Attempt to make TARGET a hard link to SOURCE; if it fails, fall back to
copy SOURCE to TARGET."
(catch 'system-error
(lambda ()
(link source target))
(lambda args
;; Perhaps SOURCE and TARGET live in a different file system, so copy
;; SOURCE.
(copy-file source target))))
(define (activate-setuid-programs programs)
"Turn PROGRAMS, a list of file names, into setuid programs stored under
%SETUID-DIRECTORY."
(define (make-setuid-program prog)
(let ((target (string-append %setuid-directory
"/" (basename prog))))
(catch 'system-error
(lambda ()
(link prog target))
(lambda args
;; Perhaps PROG and TARGET live in a different file system, so copy
;; PROG.
(copy-file prog target)))
(link-or-copy prog target)
(chown target 0 0)
(chmod target #o6555)))