[bug#44623] [PATCH] archive: Warn about replacing an ACL symlink.

[Ludovic Courtès]

Tobias Geerinckx-Rice <me@tobias.gr> skribis:

> * guix/scripts/archive.scm (authorize-key): Warn when %ACL-FILE is a
> symbolic link and print an additional hint for Guix System users.

Oh, I was convinced that ‘guix archive --authorize’ would now fail on
Guix System, but indeed it doesn’t, due to the canonical rename trick.

> +  ;; Warn about potentially volatile ACLs, but continue: system 
> reconfiguration
> +  ;; might not be possible without (newly-authorized) substitutes.
> +  (when (and (access? %acl-file F_OK)
> +             (eq? 'symlink (stat:type (lstat %acl-file))))

You can do both at once (thus avoiding a TOCTTOU race) with:

  (let ((stat (false-if-exception (lstat %acl-file))))
    (when (and stat …)
      …))

Otherwise LGTM (for ‘master’), thanks!

Ludo’.