services: admin: Improve use of unattended-upgrade reboot? field.

This ensures the unattended upgrade job successfully reboots regardless of the
value for services-to-restart. Previously the mcron service may be restarted
which would halt script execution before the system rebooted.

* gnu/services/admin.scm (unattended-upgrade-mcron-jobs): Do not restart
services when reboot? is #t.
* doc/guix.texi (Unattended Upgrades): Document it.

Change-Id: I8e486a764ec1dc5c3090130cc447a0cc3f5a2e00
Signed-off-by: Ludovic Courtès <ludo@gnu.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/gnu/services/admin.scm b/gnu/services/admin.scm
index 4882883878a..24ff659a01b 100644
--- a/gnu/services/admin.scm
+++ b/gnu/services/admin.scm
@@ -512,11 +512,13 @@ which lets you search for packages that provide a given file.")
                       #$(string-append (number->string expiration)
                                        "s")))
 
-            (format #t "~a restarting services...~%" (timestamp))
-            (for-each restart-service '#$services)
+            (unless #$reboot?
+              ;; Rebooting effectively restarts services anyway and execution
+              ;; would be halted here if mcron is restarted.
+              (format #t "~a restarting services...~%" (timestamp))
+              (for-each restart-service '#$services))
 
-            ;; XXX: If 'mcron' has been restarted, perhaps this isn't
-            ;; reached.
+            ;; XXX: If 'mcron' has been restarted, this is not reached.
             (format #t "~a upgrade complete~%" (timestamp))
 
             ;; Stopping the root shepherd service triggers a reboot.