WIP: Build image from scratch / without NixOS.

An experiment to see if we can minimize the PatOS project even further,
and not have to adapt NixOS packages and config for our needs.

systemd/0017-meson.build-do-not-create-systemdstatedir.patch

@@ -0,0 +1,21 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: nikstur <nikstur@outlook.com>
+Date: Mon, 6 Nov 2023 22:51:38 +0100
+Subject: [PATCH] meson.build: do not create systemdstatedir
+
+---
+ meson.build | 1 -
+ 1 file changed, 1 deletion(-)
+
+diff --git a/meson.build b/meson.build
+index bffda86845..cb5dcec0f9 100644
+--- a/meson.build
++++ b/meson.build
+@@ -2781,7 +2781,6 @@ install_data('LICENSE.GPL2',
+ install_subdir('LICENSES',
+                install_dir : docdir)
+ 
+-install_emptydir(systemdstatedir)
+ 
+ #####################################################################
+ 

systemd/default.nix

@@ -3,6 +3,7 @@
   lib,
   pkgs,
   stdenv,
+  targetPackages,
   ...
 }:
 let
@@ -29,7 +30,12 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-GvRn55grHWR6M+tA86RMzqinuXNpPZzRB4ApuGN/ZvU=";
   };
 
+  patches = [
+    ./0017-meson.build-do-not-create-systemdstatedir.patch
+  ];
+
   nativeBuildInputs = with pkgs; [
+    bash
     pkg-config
     makeBinaryWrapper
     gperf
@@ -61,6 +67,13 @@ stdenv.mkDerivation (finalAttrs: {
     buildPackages.llvmPackages.libllvm
   ];
 
+  outputs = [
+    "out"
+    "dev"
+  ];
+
+  separateDebugInfo = true;
+
   autoPatchelfFlags = [ "--keep-libc" ];
 
   hardeningDisable = [
@@ -113,7 +126,47 @@ stdenv.mkDerivation (finalAttrs: {
 
   mesonBuildType = "release";
 
+  doCheck = false; # fails a bunch of tests
+
+  preConfigure = ''
+    mesonFlagsArray+=(-Dntp-servers="0.europe.pool.ntp.org 1.europe.pool.ntp.org 2.europe.pool.ntp.org 3.europe.pool.ntp.org")
+    export LC_ALL="en_US.UTF-8";
+  '';
+
+  postPatch =
+    ''
+      substituteInPlace src/basic/path-util.h --replace "@defaultPathNormal@" "${placeholder "out"}/bin/"
+    ''
+    + ''
+      substituteInPlace meson.build \
+        --replace "find_program('clang'" "find_program('${stdenv.cc.targetPrefix}clang'"
+    ''
+    + ''
+      substituteInPlace src/ukify/ukify.py \
+        --replace \
+        "'readelf'" \
+        "'${targetPackages.stdenv.cc.bintools.targetPrefix}readelf'" \
+        --replace \
+        "/usr/lib/systemd/boot/efi" \
+        "$out/lib/systemd/boot/efi"
+    ''
+    # Finally, patch shebangs in scripts used at build time. This must not patch
+    # scripts that will end up in the output, to avoid build platform references
+    # when cross-compiling.
+    + ''
+      shopt -s extglob
+      patchShebangs tools test src/!(rpm|kernel-install|ukify) src/kernel-install/test-kernel-install.sh
+    '';
+
+  # trigger the test -n "$DESTDIR" || mutate in upstreams build system
+  preInstall = ''
+    export DESTDIR=/
+  '';
+
   mesonFlags = [
+
+    "--prefix=${placeholder "out"}"
+
     # Options
 
     # We bump this attribute on every (major) version change to ensure that we
@@ -129,6 +182,17 @@ stdenv.mkDerivation (finalAttrs: {
     (lib.mesonOption "mode" "release")
     (lib.mesonOption "tty-gid" "3") # tty in NixOS has gid 3
 
+    (lib.mesonOption "debug-shell" "${pkgs.bashInteractive}/bin/bash")
+    (lib.mesonOption "pamconfdir" "${placeholder "out"}/etc/pam.d")
+    (lib.mesonOption "shellprofiledir" "${placeholder "out"}/etc/profile.d")
+    (lib.mesonOption "kmod-path" "${pkgs.kmod}/bin/kmod")
+    (lib.mesonOption "dbuspolicydir" "${placeholder "out"}/share/dbus-1/system.d")
+    (lib.mesonOption "dbussessionservicedir" "${placeholder "out"}/share/dbus-1/services")
+    (lib.mesonOption "dbussystemservicedir" "${placeholder "out"}/share/dbus-1/system-services")
+    # pkgconfig
+    (lib.mesonOption "pkgconfiglibdir" "${placeholder "dev"}/lib/pkgconfig")
+    (lib.mesonOption "pkgconfigdatadir" "${placeholder "dev"}/share/pkgconfig")
+
     # SBAT
     (lib.mesonOption "sbat-distro" "patos")
     (lib.mesonOption "sbat-distro-summary" "PatOS")

systemd/result

@@ -0,0 +1 @@
+/nix/store/jw8923rfwly76yb8ynp5r65cvg4g9m0f-systemd-257.3