nixpkgs/modules/system/boot/systemd.nix
Eelco Dolstra 337423af8e Backdoor: depend on /dev/hvc0
Systemd is the shit: units can declare a dependency on the appearance
of device nodes.  Yay!
2012-06-19 17:36:02 -04:00

405 lines
9.8 KiB
Nix

{ config, pkgs, ... }:
with pkgs.lib;
let
servicesOptions = {
description = mkOption {
default = "";
types = types.uniq types.string;
description = "Description of this unit used in systemd messages and progress indicators.";
};
requires = mkOption {
default = [];
types = types.listOf types.string;
description = ''
Start the specified units when this unit is started, and stop
this unit when the specified units are stopped or fail.
'';
};
wants = mkOption {
default = [];
types = types.listOf types.string;
description = ''
Start the specified units when this unit is started.
'';
};
after = mkOption {
default = [];
types = types.listOf types.string;
description = ''
If the specified units are started at the same time as
this unit, delay this unit until they have started.
'';
};
before = mkOption {
default = [];
types = types.listOf types.string;
description = ''
If the specified units are started at the same time as
this unit, delay them until this unit has started.
'';
};
wantedBy = mkOption {
default = [];
types = types.listOf types.string;
description = "Start this unit when the specified units are started.";
};
environment = mkOption {
default = {};
type = types.attrs;
example = { PATH = "/foo/bar/bin"; LANG = "nl_NL.UTF-8"; };
description = "Environment variables passed to the services's processes.";
};
path = mkOption {
default = [];
apply = ps: "${makeSearchPath "bin" ps}:${makeSearchPath "sbin" ps}";
description = ''
Packages added to the service's <envar>PATH</envar>
environment variable. Both the <filename>bin</filename>
and <filename>sbin</filename> subdirectories of each
package are added.
'';
};
serviceConfig = mkOption {
default = "";
type = types.string;
description = ''
Contents of the <literal>[Service]</literal> section of the unit.
See <citerefentry><refentrytitle>systemd.unit</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
script = mkOption {
type = types.uniq types.string;
default = "";
description = "Shell commands executed as the service's main process.";
};
preStart = mkOption {
type = types.string;
default = "";
description = ''
Shell commands executed before the service's main process
is started.
'';
};
};
servicesConfig = { name, config, ... }: {
config = {
# Default path for systemd services. Should be quite minimal.
path =
[ pkgs.coreutils
pkgs.findutils
pkgs.gnugrep
pkgs.gnused
systemd
];
};
};
cfg = config.boot.systemd;
systemd = pkgs.systemd;
makeUnit = name: unit:
pkgs.writeTextFile { name = "unit"; inherit (unit) text; destination = "/${name}"; };
upstreamUnits =
[ # Targets.
"basic.target"
"sysinit.target"
"sockets.target"
"graphical.target"
"multi-user.target"
"getty.target"
"rescue.target"
"network.target"
"nss-lookup.target"
"nss-user-lookup.target"
"syslog.target"
"time-sync.target"
# Udev.
"systemd-udev-control.socket"
"systemd-udev-kernel.socket"
"systemd-udev.service"
"systemd-udev-settle.service"
"systemd-udev-trigger.service"
# Login stuff.
"systemd-logind.service"
"autovt@.service"
"systemd-vconsole-setup.service"
"systemd-user-sessions.service"
"dbus-org.freedesktop.login1.service"
"user@.service"
# Journal.
"systemd-journald.socket"
"systemd-journald.service"
# SysV init compatibility.
"systemd-initctl.socket"
"systemd-initctl.service"
"runlevel0.target"
"runlevel1.target"
"runlevel2.target"
"runlevel3.target"
"runlevel4.target"
"runlevel5.target"
"runlevel6.target"
# Random seed.
"systemd-random-seed-load.service"
"systemd-random-seed-save.service"
# Utmp maintenance.
"systemd-update-utmp-runlevel.service"
"systemd-update-utmp-shutdown.service"
# Filesystems.
"fsck@.service"
"fsck-root.service"
"systemd-remount-fs.service"
"local-fs.target"
"local-fs-pre.target"
"remote-fs.target"
"remote-fs-pre.target"
"swap.target"
"dev-hugepages.mount"
"dev-mqueue.mount"
"sys-fs-fuse-connections.mount"
"sys-kernel-config.mount"
"sys-kernel-debug.mount"
# Hibernate / suspend.
"hibernate.target"
"hibernate.service"
"suspend.target"
"suspend.service"
"sleep.target"
# Reboot stuff.
"reboot.target"
"reboot.service"
"poweroff.target"
"poweroff.service"
"halt.target"
"halt.service"
"ctrl-alt-del.target"
"shutdown.target"
"umount.target"
"final.target"
# Password entry.
"systemd-ask-password-console.path"
"systemd-ask-password-console.service"
"systemd-ask-password-wall.path"
"systemd-ask-password-wall.service"
# Misc.
"syslog.socket"
];
upstreamWants =
[ "basic.target.wants"
"sysinit.target.wants"
"sockets.target.wants"
"local-fs.target.wants"
"multi-user.target.wants"
"shutdown.target.wants"
];
rescueService =
''
[Unit]
Description=Rescue Shell
DefaultDependencies=no
Conflicts=shutdown.target
After=sysinit.target
Before=shutdown.target
[Service]
Environment=HOME=/root
WorkingDirectory=/root
ExecStartPre=-${pkgs.coreutils}/bin/echo 'Welcome to rescue mode. Use "systemctl default" or ^D to enter default mode.'
#ExecStart=-/sbin/sulogin
ExecStart=-${pkgs.bashInteractive}/bin/bash --login
ExecStopPost=-${systemd}/bin/systemctl --fail --no-block default
Type=idle
StandardInput=tty-force
StandardOutput=inherit
StandardError=inherit
KillMode=process
# Bash ignores SIGTERM, so we send SIGHUP instead, to ensure that bash
# terminates cleanly.
KillSignal=SIGHUP
'';
serviceToUnit = name: def:
{ inherit (def) wantedBy;
text =
''
[Unit]
${optionalString (def.description != "") ''
Description=${def.description}
''}
Requires=${concatStringsSep " " def.requires}
Wants=${concatStringsSep " " def.wants}
Before=${concatStringsSep " " def.before}
After=${concatStringsSep " " def.after}
[Service]
Environment=PATH=${def.path}
${concatMapStrings (n: "Environment=${n}=${getAttr n def.environment}\n") (attrNames def.environment)}
${optionalString (def.preStart != "") ''
ExecStartPre=${pkgs.writeScript "${name}-prestart.sh" ''
#! ${pkgs.stdenv.shell} -e
${def.preStart}
''}
''}
${optionalString (def.script != "") ''
ExecStart=${pkgs.writeScript "${name}.sh" ''
#! ${pkgs.stdenv.shell} -e
${def.script}
''}
''}
${def.serviceConfig}
'';
};
nixosUnits = mapAttrsToList makeUnit cfg.units;
units = pkgs.runCommand "units" { preferLocalBuild = true; }
''
mkdir -p $out/system
for i in ${toString upstreamUnits}; do
fn=${systemd}/example/systemd/system/$i
[ -e $fn ]
if [ -L $fn ]; then
cp -pd $fn $out/system/
else
ln -s $fn $out/system
fi
done
for i in ${toString upstreamWants}; do
fn=${systemd}/example/systemd/system/$i
[ -e $fn ]
x=$out/system/$(basename $fn)
mkdir $x
for i in $fn/*; do
y=$x/$(basename $i)
cp -pd $i $y
if ! [ -e $y ]; then rm -v $y; fi
done
done
for i in ${toString nixosUnits}; do
cp $i/* $out/system
done
${concatStrings (mapAttrsToList (name: unit:
concatMapStrings (name2: ''
mkdir -p $out/system/${name2}.wants
ln -sfn ../${name} $out/system/${name2}.wants/
'') unit.wantedBy) cfg.units)}
ln -s ${cfg.defaultUnit} $out/system/default.target
''; # */
in
{
###### interface
options = {
boot.systemd.units = mkOption {
description = "Definition of systemd units.";
default = {};
type = types.attrsOf types.optionSet;
options = {
text = mkOption {
types = types.uniq types.string;
description = "Text of this systemd unit.";
};
wantedBy = mkOption {
default = [];
types = types.listOf types.string;
description = "Units that want (i.e. depend on) this unit.";
};
};
};
boot.systemd.services = mkOption {
description = "Definition of systemd services.";
default = {};
type = types.attrsOf types.optionSet;
options = [ servicesOptions servicesConfig ];
};
boot.systemd.defaultUnit = mkOption {
default = "multi-user.target";
type = types.uniq types.string;
description = "Default unit started when the system boots.";
};
};
###### implementation
config = {
system.build.systemd = systemd;
system.build.units = units;
environment.systemPackages = [ systemd ];
environment.etc =
[ { source = units;
target = "systemd";
}
];
boot.systemd.units =
{ "rescue.service".text = rescueService; }
// mapAttrs serviceToUnit cfg.services;
};
}