Enable direct installation with native systemd

flake.nix

@@ -22,6 +22,7 @@
  ./modules/docker-native.nix
  ./modules/installer.nix
  ./modules/interop.nix
+ ./modules/systemd-tarball.nix
  ./modules/version.nix
  ./modules/wsl-conf.nix
  ./modules/wsl-distro.nix

modules/systemd-tarball.nix

@@ -0,0 +1,82 @@
+{ config, pkgs, lib, ... }:
+with builtins; with lib;
+let
+ pkgs2storeContents = map (x: { object = x; symlink = "none"; });
+
+ nixpkgs = lib.cleanSource pkgs.path;
+
+ channelSources = pkgs.runCommand "nixos-${config.system.nixos.version}"
+ { preferLocalBuild = true; }
+ ''
+ mkdir -p $out
+ cp -prd ${nixpkgs.outPath} $out/nixos
+ chmod -R u+w $out/nixos
+ if [ ! -e $out/nixos/nixpkgs ]; then
+ ln -s . $out/nixos/nixpkgs
+ fi
+ echo -n ${toString config.system.nixos.revision} > $out/nixos/.git-revision
+ echo -n ${toString config.system.nixos.versionSuffix} > $out/nixos/.version-suffix
+ echo ${toString config.system.nixos.versionSuffix} | sed -e s/pre// > $out/nixos/svn-revision
+ '';
+
+ preparer = pkgs.writeShellScriptBin "wsl-prepare" ''
+ set -e
+
+ # Set system profile
+ system=${config.system.build.toplevel}
+ ./$system/sw/bin/nix-store --store "$PWD" --load-db < ./nix-path-registration
+ rm ./nix-path-registration
+ ./$system/sw/bin/nix-env --store "$PWD" -p ./nix/var/nix/profiles/system --set $system
+
+ # Set channel
+ mkdir -p ./nix/var/nix/profiles/per-user/root
+ ./$system/sw/bin/nix-env --store "$PWD" -p ./nix/var/nix/profiles/per-user/root/channels --set ${channelSources}
+ mkdir -m 0700 -p ./root/.nix-defexpr
+ ln -s /nix/var/nix/profiles/per-user/root/channels ./root/.nix-defexpr/channels
+
+ mkdir -p sbin nix/nixos-wsl/entrypoint
+ ln -s ${pkgs.wslNativeUtils}/bin/systemd-shim ./sbin/init
+
+ ${lib.optionalString config.wsl.tarball.includeConfig ''
+ # Copy the system configuration
+ mkdir -p ./etc/nixos/nixos-wsl
+ cp -R ${lib.cleanSource ../.}/. ./etc/nixos/nixos-wsl
+ mv ./etc/nixos/nixos-wsl/configuration.nix ./etc/nixos/configuration.nix
+ # Patch the import path to avoid having a flake.nix in /etc/nixos
+ sed -i 's|import \./default\.nix|import \./nixos-wsl|' ./etc/nixos/configuration.nix
+ ''}
+ '';
+in
+{
+
+ config = mkIf config.wsl.enable {
+ assertions = [{
+ assertion = config.wsl.nativeSystemd;
+ message = "config.wsl.nativeSystemd must be true in order to build a systemd-tarball!";
+ }];
+
+ system.build.systemd-tarball = pkgs.callPackage "${nixpkgs}/nixos/lib/make-system-tarball.nix" {
+
+ contents = [
+ # WSL needs this before first activation
+ { inherit (config.environment.etc."wsl.conf") source; target = "/etc/wsl.conf"; }
+ ];
+
+ fileName = "nixos-wsl-${pkgs.hostPlatform.system}";
+
+ storeContents = pkgs2storeContents [
+ config.system.build.toplevel
+ channelSources
+ preparer
+ ];
+
+ extraCommands = "${preparer}/bin/wsl-prepare";
+ extraArgs = "--hard-dereference";
+
+ # Use gzip
+ compressCommand = "gzip";
+ compressionExtension = ".gz";
+ };
+
+ };
+}

modules/wsl-distro.nix

@@ -50,8 +50,6 @@ in
  automountPath = cfg.wslConf.automount.root;
  defaultUser = config.users.users.${cfg.defaultUser};
  };
-
- nativeUtils = pkgs.callPackage ../scripts/native-utils { };
  in
  mkIf cfg.enable (
  mkMerge [
@@ -82,6 +80,12 @@ in
  ];
  };
 
+ nixpkgs.overlays = [
+ (_: prev: {
+ wslNativeUtils = prev.callPackage ../scripts/native-utils { };
+ })
+ ];
+
  # dhcp is handled by windows
  networking.dhcpcd.enable = false;
 
@@ -193,7 +197,7 @@ in
  shimSystemd = stringAfter [ ] ''
  echo "setting up /sbin/init shim..."
  mkdir -p /sbin
- ln -sf ${nativeUtils}/bin/systemd-shim /sbin/init
+ ln -sf ${pkgs.wslNativeUtils}/bin/systemd-shim /sbin/init
  '';
  setupLogin = lib.mkIf cfg.populateBin (stringAfter [ ] ''
  echo "setting up /bin/login..."
@@ -206,7 +210,7 @@ in
  # preserve $PATH from parent
  variables.PATH = [ "$PATH" ];
  extraInit = ''
- eval $(${nativeUtils}/bin/split-path --automount-root="${cfg.wslConf.automount.root}" ${lib.optionalString cfg.interop.includePath "--include-interop"})
+ eval $(${pkgs.wslNativeUtils}/bin/split-path --automount-root="${cfg.wslConf.automount.root}" ${lib.optionalString cfg.interop.includePath "--include-interop"})
  '';
  };
  })