nixpkgs/nixos/modules/services/networking/ifplugd.nix
Eelco Dolstra 29027fd1e1 Rewrite ‘with pkgs.lib’ -> ‘with lib’
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
2014-04-14 16:26:48 +02:00

88 lines
2.1 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
inherit (pkgs) ifplugd;
cfg = config.networking.interfaceMonitor;
# The ifplugd action script, which is called whenever the link
# status changes (i.e., a cable is plugged in or unplugged).
plugScript = pkgs.writeScript "ifplugd.action"
''
#! ${pkgs.stdenv.shell}
iface="$1"
status="$2"
${cfg.commands}
'';
in
{
###### interface
options = {
networking.interfaceMonitor.enable = mkOption {
type = types.bool;
default = false;
description = ''
If <literal>true</literal>, monitor Ethernet interfaces for
cables being plugged in or unplugged. When this occurs, the
commands specified in
<option>networking.interfaceMonitor.commands</option> are
executed.
'';
};
networking.interfaceMonitor.beep = mkOption {
type = types.bool;
default = false;
description = ''
If <literal>true</literal>, beep when an Ethernet cable is
plugged in or unplugged.
'';
};
networking.interfaceMonitor.commands = mkOption {
type = types.lines;
default = "";
description = ''
Shell commands to be executed when the link status of an
interface changes. On invocation, the shell variable
<varname>iface</varname> contains the name of the interface,
while the variable <varname>status</varname> contains either
<literal>up</literal> or <literal>down</literal> to indicate
the new status.
'';
};
};
###### implementation
config = mkIf cfg.enable {
jobs.ifplugd =
{ description = "Network interface connectivity monitor";
startOn = "started network-interfaces";
stopOn = "stopping network-interfaces";
exec =
''
${ifplugd}/sbin/ifplugd --no-daemon --no-startup --no-shutdown \
${if config.networking.interfaceMonitor.beep then "" else "--no-beep"} \
--run ${plugScript}
'';
};
environment.systemPackages = [ ifplugd ];
};
}