nixpkgs-suyu/nixos/lib/systemd-lib.nix
Florian Klink e3083decc4 systemd-initrd, systemd-lib: drop initrdServiceToUnit
We can just use serviceToUnit here.
2022-03-24 18:57:16 +01:00

449 lines
15 KiB
Nix
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

{ config, lib, pkgs }:
with lib;
let
cfg = config.systemd;
lndir = "${pkgs.buildPackages.xorg.lndir}/bin/lndir";
systemd = cfg.package;
in rec {
shellEscape = s: (replaceChars [ "\\" ] [ "\\\\" ] s);
mkPathSafeName = lib.replaceChars ["@" ":" "\\" "[" "]"] ["-" "-" "-" "" ""];
# a type for options that take a unit name
unitNameType = types.strMatching "[a-zA-Z0-9@%:_.\\-]+[.](service|socket|device|mount|automount|swap|target|path|timer|scope|slice)";
makeUnit = name: unit:
if unit.enable then
pkgs.runCommand "unit-${mkPathSafeName name}"
{ preferLocalBuild = true;
allowSubstitutes = false;
inherit (unit) text;
}
''
mkdir -p $out
echo -n "$text" > $out/${shellEscape name}
''
else
pkgs.runCommand "unit-${mkPathSafeName name}-disabled"
{ preferLocalBuild = true;
allowSubstitutes = false;
}
''
mkdir -p $out
ln -s /dev/null $out/${shellEscape name}
'';
boolValues = [true false "yes" "no"];
digits = map toString (range 0 9);
isByteFormat = s:
let
l = reverseList (stringToCharacters s);
suffix = head l;
nums = tail l;
in elem suffix (["K" "M" "G" "T"] ++ digits)
&& all (num: elem num digits) nums;
assertByteFormat = name: group: attr:
optional (attr ? ${name} && ! isByteFormat attr.${name})
"Systemd ${group} field `${name}' must be in byte format [0-9]+[KMGT].";
hexChars = stringToCharacters "0123456789abcdefABCDEF";
isMacAddress = s: stringLength s == 17
&& flip all (splitString ":" s) (bytes:
all (byte: elem byte hexChars) (stringToCharacters bytes)
);
assertMacAddress = name: group: attr:
optional (attr ? ${name} && ! isMacAddress attr.${name})
"Systemd ${group} field `${name}' must be a valid mac address.";
isPort = i: i >= 0 && i <= 65535;
assertPort = name: group: attr:
optional (attr ? ${name} && ! isPort attr.${name})
"Error on the systemd ${group} field `${name}': ${attr.name} is not a valid port number.";
assertValueOneOf = name: values: group: attr:
optional (attr ? ${name} && !elem attr.${name} values)
"Systemd ${group} field `${name}' cannot have value `${toString attr.${name}}'.";
assertHasField = name: group: attr:
optional (!(attr ? ${name}))
"Systemd ${group} field `${name}' must exist.";
assertRange = name: min: max: group: attr:
optional (attr ? ${name} && !(min <= attr.${name} && max >= attr.${name}))
"Systemd ${group} field `${name}' is outside the range [${toString min},${toString max}]";
assertMinimum = name: min: group: attr:
optional (attr ? ${name} && attr.${name} < min)
"Systemd ${group} field `${name}' must be greater than or equal to ${toString min}";
assertOnlyFields = fields: group: attr:
let badFields = filter (name: ! elem name fields) (attrNames attr); in
optional (badFields != [ ])
"Systemd ${group} has extra fields [${concatStringsSep " " badFields}].";
assertInt = name: group: attr:
optional (attr ? ${name} && !isInt attr.${name})
"Systemd ${group} field `${name}' is not an integer";
checkUnitConfig = group: checks: attrs: let
# We're applied at the top-level type (attrsOf unitOption), so the actual
# unit options might contain attributes from mkOverride and mkIf that we need to
# convert into single values before checking them.
defs = mapAttrs (const (v:
if v._type or "" == "override" then v.content
else if v._type or "" == "if" then v.content
else v
)) attrs;
errors = concatMap (c: c group defs) checks;
in if errors == [] then true
else builtins.trace (concatStringsSep "\n" errors) false;
toOption = x:
if x == true then "true"
else if x == false then "false"
else toString x;
attrsToSection = as:
concatStrings (concatLists (mapAttrsToList (name: value:
map (x: ''
${name}=${toOption x}
'')
(if isList value then value else [value]))
as));
generateUnits = { allowCollisions ? true, type, units, upstreamUnits, upstreamWants, packages ? cfg.packages, package ? cfg.package }:
let
typeDir = ({
system = "system";
initrd = "system";
user = "user";
nspawn = "nspawn";
}).${type};
in pkgs.runCommand "${type}-units"
{ preferLocalBuild = true;
allowSubstitutes = false;
} ''
mkdir -p $out
# Copy the upstream systemd units we're interested in.
for i in ${toString upstreamUnits}; do
fn=${package}/example/systemd/${typeDir}/$i
if ! [ -e $fn ]; then echo "missing $fn"; false; fi
if [ -L $fn ]; then
target="$(readlink "$fn")"
if [ ''${target:0:3} = ../ ]; then
ln -s "$(readlink -f "$fn")" $out/
else
cp -pd $fn $out/
fi
else
ln -s $fn $out/
fi
done
# Copy .wants links, but only those that point to units that
# we're interested in.
for i in ${toString upstreamWants}; do
fn=${package}/example/systemd/${typeDir}/$i
if ! [ -e $fn ]; then echo "missing $fn"; false; fi
x=$out/$(basename $fn)
mkdir $x
for i in $fn/*; do
y=$x/$(basename $i)
cp -pd $i $y
if ! [ -e $y ]; then rm $y; fi
done
done
# Symlink all units provided listed in systemd.packages.
packages="${toString packages}"
# Filter duplicate directories
declare -A unique_packages
for k in $packages ; do unique_packages[$k]=1 ; done
for i in ''${!unique_packages[@]}; do
for fn in $i/etc/systemd/${typeDir}/* $i/lib/systemd/${typeDir}/*; do
if ! [[ "$fn" =~ .wants$ ]]; then
if [[ -d "$fn" ]]; then
targetDir="$out/$(basename "$fn")"
mkdir -p "$targetDir"
${lndir} "$fn" "$targetDir"
else
ln -s $fn $out/
fi
fi
done
done
# Symlink all units defined by systemd.units. If these are also
# provided by systemd or systemd.packages, then add them as
# <unit-name>.d/overrides.conf, which makes them extend the
# upstream unit.
for i in ${toString (mapAttrsToList (n: v: v.unit) units)}; do
fn=$(basename $i/*)
if [ -e $out/$fn ]; then
if [ "$(readlink -f $i/$fn)" = /dev/null ]; then
ln -sfn /dev/null $out/$fn
else
${if allowCollisions then ''
mkdir -p $out/$fn.d
ln -s $i/$fn $out/$fn.d/overrides.conf
'' else ''
echo "Found multiple derivations configuring $fn!"
exit 1
''}
fi
else
ln -fs $i/$fn $out/
fi
done
# Create service aliases from aliases option.
${concatStrings (mapAttrsToList (name: unit:
concatMapStrings (name2: ''
ln -sfn '${name}' $out/'${name2}'
'') unit.aliases) units)}
# Create .wants and .requires symlinks from the wantedBy and
# requiredBy options.
${concatStrings (mapAttrsToList (name: unit:
concatMapStrings (name2: ''
mkdir -p $out/'${name2}.wants'
ln -sfn '../${name}' $out/'${name2}.wants'/
'') unit.wantedBy) units)}
${concatStrings (mapAttrsToList (name: unit:
concatMapStrings (name2: ''
mkdir -p $out/'${name2}.requires'
ln -sfn '../${name}' $out/'${name2}.requires'/
'') unit.requiredBy) units)}
${optionalString (type == "system") ''
# Stupid misc. symlinks.
ln -s ${cfg.defaultUnit} $out/default.target
ln -s ${cfg.ctrlAltDelUnit} $out/ctrl-alt-del.target
ln -s rescue.target $out/kbrequest.target
mkdir -p $out/getty.target.wants/
ln -s ../autovt@tty1.service $out/getty.target.wants/
ln -s ../remote-fs.target $out/multi-user.target.wants/
''}
''; # */
makeJobScript = name: text:
let
scriptName = replaceChars [ "\\" "@" ] [ "-" "_" ] (shellEscape name);
out = (pkgs.writeShellScriptBin scriptName ''
set -e
${text}
'').overrideAttrs (_: {
# The derivation name is different from the script file name
# to keep the script file name short to avoid cluttering logs.
name = "unit-script-${scriptName}";
});
in "${out}/bin/${scriptName}";
unitConfig = { config, options, ... }: {
config = {
unitConfig =
optionalAttrs (config.requires != [])
{ Requires = toString config.requires; }
// optionalAttrs (config.wants != [])
{ Wants = toString config.wants; }
// optionalAttrs (config.after != [])
{ After = toString config.after; }
// optionalAttrs (config.before != [])
{ Before = toString config.before; }
// optionalAttrs (config.bindsTo != [])
{ BindsTo = toString config.bindsTo; }
// optionalAttrs (config.partOf != [])
{ PartOf = toString config.partOf; }
// optionalAttrs (config.conflicts != [])
{ Conflicts = toString config.conflicts; }
// optionalAttrs (config.requisite != [])
{ Requisite = toString config.requisite; }
// optionalAttrs (config.restartTriggers != [])
{ X-Restart-Triggers = toString config.restartTriggers; }
// optionalAttrs (config.reloadTriggers != [])
{ X-Reload-Triggers = toString config.reloadTriggers; }
// optionalAttrs (config.description != "") {
Description = config.description; }
// optionalAttrs (config.documentation != []) {
Documentation = toString config.documentation; }
// optionalAttrs (config.onFailure != []) {
OnFailure = toString config.onFailure; }
// optionalAttrs (options.startLimitIntervalSec.isDefined) {
StartLimitIntervalSec = toString config.startLimitIntervalSec;
} // optionalAttrs (options.startLimitBurst.isDefined) {
StartLimitBurst = toString config.startLimitBurst;
};
};
};
mkServiceConfig = path: { name, config, ... }: {
config = mkMerge
[ { # Default path for systemd services. Should be quite minimal.
path = mkAfter path;
environment.PATH = mkIf (config.path != []) "${makeBinPath config.path}:${makeSearchPathOutput "bin" "sbin" config.path}";
}
(mkIf (config.preStart != "")
{ serviceConfig.ExecStartPre =
[ (makeJobScript "${name}-pre-start" config.preStart) ];
})
(mkIf (config.script != "")
{ serviceConfig.ExecStart =
makeJobScript "${name}-start" config.script + " " + config.scriptArgs;
})
(mkIf (config.postStart != "")
{ serviceConfig.ExecStartPost =
[ (makeJobScript "${name}-post-start" config.postStart) ];
})
(mkIf (config.reload != "")
{ serviceConfig.ExecReload =
makeJobScript "${name}-reload" config.reload;
})
(mkIf (config.preStop != "")
{ serviceConfig.ExecStop =
makeJobScript "${name}-pre-stop" config.preStop;
})
(mkIf (config.postStop != "")
{ serviceConfig.ExecStopPost =
makeJobScript "${name}-post-stop" config.postStop;
})
];
};
serviceConfig = mkServiceConfig [
pkgs.coreutils
pkgs.findutils
pkgs.gnugrep
pkgs.gnused
systemd
];
initrdServiceConfig = mkServiceConfig [];
mountConfig = { config, ... }: {
config = {
mountConfig =
{ What = config.what;
Where = config.where;
} // optionalAttrs (config.type != "") {
Type = config.type;
} // optionalAttrs (config.options != "") {
Options = config.options;
};
};
};
automountConfig = { config, ... }: {
config = {
automountConfig =
{ Where = config.where;
};
};
};
commonUnitText = def: ''
[Unit]
${attrsToSection def.unitConfig}
'';
targetToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text =
''
[Unit]
${attrsToSection def.unitConfig}
'';
};
serviceToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text = commonUnitText def +
''
[Service]
${let env = cfg.globalEnvironment // def.environment;
in concatMapStrings (n:
let s = optionalString (env.${n} != null)
"Environment=${builtins.toJSON "${n}=${env.${n}}"}\n";
# systemd max line length is now 1MiB
# https://github.com/systemd/systemd/commit/e6dde451a51dc5aaa7f4d98d39b8fe735f73d2af
in if stringLength s >= 1048576 then throw "The value of the environment variable ${n} in systemd service ${name}.service is too long." else s) (attrNames env)}
${if def.reloadIfChanged then ''
X-ReloadIfChanged=true
'' else if !def.restartIfChanged then ''
X-RestartIfChanged=false
'' else ""}
${optionalString (!def.stopIfChanged) "X-StopIfChanged=false"}
${attrsToSection def.serviceConfig}
'';
};
socketToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text = commonUnitText def +
''
[Socket]
${attrsToSection def.socketConfig}
${concatStringsSep "\n" (map (s: "ListenStream=${s}") def.listenStreams)}
${concatStringsSep "\n" (map (s: "ListenDatagram=${s}") def.listenDatagrams)}
'';
};
timerToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text = commonUnitText def +
''
[Timer]
${attrsToSection def.timerConfig}
'';
};
pathToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text = commonUnitText def +
''
[Path]
${attrsToSection def.pathConfig}
'';
};
mountToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text = commonUnitText def +
''
[Mount]
${attrsToSection def.mountConfig}
'';
};
automountToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text = commonUnitText def +
''
[Automount]
${attrsToSection def.automountConfig}
'';
};
sliceToUnit = name: def:
{ inherit (def) aliases wantedBy requiredBy enable;
text = commonUnitText def +
''
[Slice]
${attrsToSection def.sliceConfig}
'';
};
}