Self-host your own digital island
ryan.freumh.org
1# nixos-mailserver: a simple mail server
2# Copyright (C) 2016-2018 Robin Raymond
3#
4# This program is free software: you can redistribute it and/or modify
5# it under the terms of the GNU General Public License as published by
6# the Free Software Foundation, either version 3 of the License, or
7# (at your option) any later version.
8#
9# This program is distributed in the hope that it will be useful,
10# but WITHOUT ANY WARRANTY; without even the implied warranty of
11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12# GNU General Public License for more details.
13#
14# You should have received a copy of the GNU General Public License
15# along with this program. If not, see <http://www.gnu.org/licenses/>
16
17{ config, pkgs, lib, ... }:
18
19with lib;
20
21let
22 cfg = config.mailserver;
23in
24{
25 config = mkIf (cfg.enable && cfg.rebootAfterKernelUpgrade.enable) {
26 systemd.services.nixos-upgrade.serviceConfig.ExecStartPost = pkgs.writeScript "post-upgrade-check" ''
27 #!${pkgs.stdenv.shell}
28
29 # Checks whether the "current" kernel is different from the booted kernel
30 # and then triggers a reboot so that the "current" kernel will be the booted one.
31 # This is just an educated guess. If the links do not differ the kernels might still be different, according to spacefrogg in #nixos.
32
33 current=$(readlink -f /run/current-system/kernel)
34 booted=$(readlink -f /run/booted-system/kernel)
35
36 if [ "$current" == "$booted" ]; then
37 echo "kernel version seems unchanged, skipping reboot" | systemd-cat --priority 4 --identifier "post-upgrade-check";
38 else
39 echo "kernel path changed, possibly a new version" | systemd-cat --priority 2 --identifier "post-upgrade-check"
40 echo "$booted" | systemd-cat --priority 2 --identifier "post-upgrade-kernel-check"
41 echo "$current" | systemd-cat --priority 2 --identifier "post-upgrade-kernel-check"
42 ${cfg.rebootAfterKernelUpgrade.method}
43 fi
44 '';
45 };
46}