add soft restart option to liminix-rebuild

instead of doing a full reboot, it runs activate / and uses
s6-rc-update to install the new service database

pkgs/min-copy-closure/liminix-rebuild.sh

@@ -2,12 +2,18 @@
 
 ssh_command=${SSH_COMMAND-ssh}
 
-if [ "$1" = "--no-reboot" ] ; then
-    reboot="true"
-    shift
-else
-    reboot="reboot"
-fi
+reboot="reboot"
+
+case "$1" in
+    "--no-reboot")
+	unset reboot
+	shift
+	;;
+    "--fast")
+	reboot="soft"
+	shift
+	;;
+esac
 
 target_host=$1
 shift
@@ -21,7 +27,16 @@ if toplevel=$(nix-build "$@" -A outputs.systemConfiguration --no-out-link); then
     echo systemConfiguration $toplevel
     min-copy-closure $target_host $toplevel
     $ssh_command $target_host $toplevel/bin/install
-    $ssh_command  $target_host "sync; source /etc/profile; reboot"
+    case "$reboot" in
+	reboot)
+	    $ssh_command $target_host "sync; source /etc/profile; reboot"
+	    ;;
+	soft)
+	    $ssh_command $target_host $toplevel/bin/restart-services
+	    ;;
+	*)
+	    ;;
+    esac
 else
     echo Rebuild failed
 fi