nixpkgs/nixos/modules/system/activation/top-level.nix
rnhmjoj 61b7cab481
treewide: use perl.withPackages when possible
Since 03eaa48 added perl.withPackages, there is a canonical way to
create a perl interpreter from a list of libraries, for use in script
shebangs or generic build inputs. This method is declarative (what we
are doing is clear), produces short shebangs[1] and needs not to wrap
existing scripts.

Unfortunately there are a few exceptions that I've found:

  1. Scripts that are calling perl with the -T switch. This makes perl
  ignore PERL5LIB, which is what perl.withPackages is using to inform
  the interpreter of the library paths.

  2. Perl packages that depends on libraries in their own path. This
  is not possible because perl.withPackages works at build time. The
  workaround is to add `-I $out/${perl.libPrefix}` to the shebang.

In all other cases I propose to switch to perl.withPackages.

[1]: https://lwn.net/Articles/779997/
2021-03-31 21:35:37 +02:00

298 lines
9.9 KiB
Nix

{ config, lib, pkgs, modules, baseModules, ... }:
with lib;
let
# This attribute is responsible for creating boot entries for
# child configuration. They are only (directly) accessible
# when the parent configuration is boot default. For example,
# you can provide an easy way to boot the same configuration
# as you use, but with another kernel
# !!! fix this
children = mapAttrs (childName: childConfig:
(import ../../../lib/eval-config.nix {
inherit baseModules;
system = config.nixpkgs.initialSystem;
modules =
(optionals childConfig.inheritParentConfig modules)
++ [ ./no-clone.nix ]
++ [ childConfig.configuration ];
}).config.system.build.toplevel
) config.specialisation;
systemBuilder =
let
kernelPath = "${config.boot.kernelPackages.kernel}/" +
"${config.system.boot.loader.kernelFile}";
initrdPath = "${config.system.build.initialRamdisk}/" +
"${config.system.boot.loader.initrdFile}";
in ''
mkdir $out
# Containers don't have their own kernel or initrd. They boot
# directly into stage 2.
${optionalString (!config.boot.isContainer) ''
if [ ! -f ${kernelPath} ]; then
echo "The bootloader cannot find the proper kernel image."
echo "(Expecting ${kernelPath})"
false
fi
ln -s ${kernelPath} $out/kernel
ln -s ${config.system.modulesTree} $out/kernel-modules
${optionalString (config.hardware.deviceTree.package != null) ''
ln -s ${config.hardware.deviceTree.package} $out/dtbs
''}
echo -n "$kernelParams" > $out/kernel-params
ln -s ${initrdPath} $out/initrd
ln -s ${config.system.build.initialRamdiskSecretAppender}/bin/append-initrd-secrets $out
ln -s ${config.hardware.firmware}/lib/firmware $out/firmware
''}
echo "$activationScript" > $out/activate
substituteInPlace $out/activate --subst-var out
chmod u+x $out/activate
unset activationScript
cp ${config.system.build.bootStage2} $out/init
substituteInPlace $out/init --subst-var-by systemConfig $out
ln -s ${config.system.build.etc}/etc $out/etc
ln -s ${config.system.path} $out/sw
ln -s "$systemd" $out/systemd
echo -n "$configurationName" > $out/configuration-name
echo -n "systemd ${toString config.systemd.package.interfaceVersion}" > $out/init-interface-version
echo -n "$nixosLabel" > $out/nixos-version
echo -n "${config.boot.kernelPackages.stdenv.hostPlatform.system}" > $out/system
mkdir $out/specialisation
${concatStringsSep "\n"
(mapAttrsToList (name: path: "ln -s ${path} $out/specialisation/${name}") children)}
mkdir $out/bin
export localeArchive="${config.i18n.glibcLocales}/lib/locale/locale-archive"
substituteAll ${./switch-to-configuration.pl} $out/bin/switch-to-configuration
chmod +x $out/bin/switch-to-configuration
echo -n "${toString config.system.extraDependencies}" > $out/extra-dependencies
${config.system.extraSystemBuilderCmds}
'';
# Putting it all together. This builds a store path containing
# symlinks to the various parts of the built configuration (the
# kernel, systemd units, init scripts, etc.) as well as a script
# `switch-to-configuration' that activates the configuration and
# makes it bootable.
baseSystem = pkgs.stdenvNoCC.mkDerivation {
name = "nixos-system-${config.system.name}-${config.system.nixos.label}";
preferLocalBuild = true;
allowSubstitutes = false;
buildCommand = systemBuilder;
inherit (pkgs) coreutils;
systemd = config.systemd.package;
shell = "${pkgs.bash}/bin/sh";
su = "${pkgs.shadow.su}/bin/su";
utillinux = pkgs.util-linux;
kernelParams = config.boot.kernelParams;
installBootLoader =
config.system.build.installBootLoader
or "echo 'Warning: do not know how to make this configuration bootable; please enable a boot loader.' 1>&2; true";
activationScript = config.system.activationScripts.script;
nixosLabel = config.system.nixos.label;
configurationName = config.boot.loader.grub.configurationName;
# Needed by switch-to-configuration.
perl = pkgs.perl.withPackages (p: with p; [ FileSlurp NetDBus XMLParser XMLTwig ]);
};
# Handle assertions and warnings
failedAssertions = map (x: x.message) (filter (x: !x.assertion) config.assertions);
baseSystemAssertWarn = if failedAssertions != []
then throw "\nFailed assertions:\n${concatStringsSep "\n" (map (x: "- ${x}") failedAssertions)}"
else showWarnings config.warnings baseSystem;
# Replace runtime dependencies
system = fold ({ oldDependency, newDependency }: drv:
pkgs.replaceDependency { inherit oldDependency newDependency drv; }
) baseSystemAssertWarn config.system.replaceRuntimeDependencies;
in
{
imports = [
(mkRemovedOptionModule [ "nesting" "clone" ] "Use `specialisation.«name» = { inheritParentConfig = true; configuration = { ... }; }` instead.")
(mkRemovedOptionModule [ "nesting" "children" ] "Use `specialisation.«name».configuration = { ... }` instead.")
];
options = {
system.build = mkOption {
internal = true;
default = {};
type = types.attrs;
description = ''
Attribute set of derivations used to setup the system.
'';
};
specialisation = mkOption {
default = {};
example = lib.literalExample "{ fewJobsManyCores.configuration = { nix.buildCores = 0; nix.maxJobs = 1; }; }";
description = ''
Additional configurations to build. If
<literal>inheritParentConfig</literal> is true, the system
will be based on the overall system configuration.
To switch to a specialised configuration
(e.g. <literal>fewJobsManyCores</literal>) at runtime, run:
<screen>
<prompt># </prompt>sudo /run/current-system/specialisation/fewJobsManyCores/bin/switch-to-configuration test
</screen>
'';
type = types.attrsOf (types.submodule (
{ ... }: {
options.inheritParentConfig = mkOption {
type = types.bool;
default = true;
description = "Include the entire system's configuration. Set to false to make a completely differently configured system.";
};
options.configuration = mkOption {
default = {};
description = "Arbitrary NixOS configuration options.";
};
})
);
};
system.boot.loader.id = mkOption {
internal = true;
default = "";
description = ''
Id string of the used bootloader.
'';
};
system.boot.loader.kernelFile = mkOption {
internal = true;
default = pkgs.stdenv.hostPlatform.linux-kernel.target;
type = types.str;
description = ''
Name of the kernel file to be passed to the bootloader.
'';
};
system.boot.loader.initrdFile = mkOption {
internal = true;
default = "initrd";
type = types.str;
description = ''
Name of the initrd file to be passed to the bootloader.
'';
};
system.copySystemConfiguration = mkOption {
type = types.bool;
default = false;
description = ''
If enabled, copies the NixOS configuration file
(usually <filename>/etc/nixos/configuration.nix</filename>)
and links it from the resulting system
(getting to <filename>/run/current-system/configuration.nix</filename>).
Note that only this single file is copied, even if it imports others.
'';
};
system.extraSystemBuilderCmds = mkOption {
type = types.lines;
internal = true;
default = "";
description = ''
This code will be added to the builder creating the system store path.
'';
};
system.extraDependencies = mkOption {
type = types.listOf types.package;
default = [];
description = ''
A list of packages that should be included in the system
closure but not otherwise made available to users. This is
primarily used by the installation tests.
'';
};
system.replaceRuntimeDependencies = mkOption {
default = [];
example = lib.literalExample "[ ({ original = pkgs.openssl; replacement = pkgs.callPackage /path/to/openssl { }; }) ]";
type = types.listOf (types.submodule (
{ ... }: {
options.original = mkOption {
type = types.package;
description = "The original package to override.";
};
options.replacement = mkOption {
type = types.package;
description = "The replacement package.";
};
})
);
apply = map ({ original, replacement, ... }: {
oldDependency = original;
newDependency = replacement;
});
description = ''
List of packages to override without doing a full rebuild.
The original derivation and replacement derivation must have the same
name length, and ideally should have close-to-identical directory layout.
'';
};
system.name = mkOption {
type = types.str;
default =
if config.networking.hostName == ""
then "unnamed"
else config.networking.hostName;
defaultText = '''networking.hostName' if non empty else "unnamed"'';
description = ''
The name of the system used in the <option>system.build.toplevel</option> derivation.
</para><para>
That derivation has the following name:
<literal>"nixos-system-''${config.system.name}-''${config.system.nixos.label}"</literal>
'';
};
};
config = {
system.extraSystemBuilderCmds =
optionalString
config.system.copySystemConfiguration
''ln -s '${import ../../../lib/from-env.nix "NIXOS_CONFIG" <nixos-config>}' \
"$out/configuration.nix"
'';
system.build.toplevel = system;
};
}