From 43d8518d8b20e799238fe8918ef0cad2edfb3b7d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lars=20Sj=C3=B6strom?= <lars@radicore.se>
Date: Mon, 17 Feb 2025 15:15:24 +0100
Subject: [PATCH] silly uki image with the systemd-ukify tooling

---
 flake.nix           | 141 +++++++++++++++++++++++++++++++++++++++++++-
 systemd/default.nix |   7 +--
 2 files changed, 141 insertions(+), 7 deletions(-)

diff --git a/flake.nix b/flake.nix
index 6a4e60f..4f004d2 100644
--- a/flake.nix
+++ b/flake.nix
@@ -15,16 +15,153 @@
     flake-utils.lib.eachDefaultSystem (
       system:
       let
-        pkgs = import nixpkgs { inherit system; };
+        pkgs = import nixpkgs {
+          inherit system;
+        };
       in
       {
         packages = {
           default = self.packages.${system}.image;
+
+          glibc = pkgs.stdenv.mkDerivation {
+            src = pkgs.fetchurl {
+              url = "mirror://gnu/glibc/glibc-2.40.tar.xz";
+              sha256 = "sha256-GaiQF16SY9dI9ieZPeb0sa+c0h4D8IDkv7Oh+sECBaI=";
+            };
+            name = "glibcStandalone";
+            enableParallelBuilding = true;
+            configureFlags = [
+              "--prefix=/"
+              "--libdir=/lib"
+              "--bindir=/bin"
+              "--sysconfdir=/etc"
+            ];
+            preConfigure =
+              ''
+                export PWD_P=$(type -tP pwd)
+                for i in configure io/ftwtest-sh; do
+                    sed -i "$i" -e "s^/bin/pwd^$PWD_P^g"
+                done
+
+                mkdir ../build
+                cd ../build
+
+                configureScript="`pwd`/../$sourceRoot/configure"
+              '';
+            nativeBuildInputs = [ pkgs.bison pkgs.python3Minimal];
+
+            outputs = [
+              "out"
+            ];
+            preInstall = ''
+              export DESTDIR=${placeholder "out"}
+            '';
+          };
+
           image = pkgs.writeShellScriptBin "image" ''
-            echo "make image here..."
+            echo "make UKI..."
+            echo ${self.packages.${system}.kernel.kernel}/bzImage
+            ${self.packages.${system}.systemd.out}/usr/bin/ukify build \
+            --linux ${self.packages.${system}.kernel.kernel}/bzImage \
+            --initrd ./initrd.gz \
+            --cmdline "console=ttyS0" \
+            -o patos.efi
           '';
 
           kernel = pkgs.callPackage ./kernel { };
+          mkinitrd = pkgs.writeShellScriptBin "mkinitrd" ''
+            echo "make initrd..."
+            mkdir -p out
+            # copy systemd
+            cp -r ${self.packages.${system}.systemd.out}/* out/
+            pushd out
+
+            chmod 755 etc usr/lib
+
+            mkdir -p dev proc sys tmp root
+            ln -sf usr/bin bin
+            ln -sf usr/sbin sbin
+            ln -sf usr/lib lib
+            ln -sf usr/lib lib64
+
+            ln -sf ../proc/self/mounts etc/mtab
+            ln -sf usr/lib/systemd/systemd init
+
+            ln -sf systemd/libsystemd-core-257.so usr/lib/
+            ln -sf systemd/libsystemd-shared-257.so usr/lib/
+
+            echo patos > ./etc/hostname
+            cat <<EOF > ./etc/os-release
+            NAME="Patos"
+            PRETTY_NAME="Patos Platform"
+            ID=patos
+            EOF
+
+            cat <<EOF > ./etc/passwd
+            root::0:0:root:/root:/bin/sh
+            bin:x:1:1:bin:/bin:/usr/bin/nologin
+            daemon:x:2:2:daemon:/:/usr/bin/nologin
+            mail:x:8:12:mail:/var/spool/mail:/usr/bin/nologin
+            ftp:x:14:11:ftp:/srv/ftp:/usr/bin/nologin
+            http:x:33:33:http:/srv/http:/usr/bin/nologin
+            uuidd:x:68:68:uuidd:/:/usr/bin/nologin
+            dbus:x:81:81:dbus:/:/usr/bin/nologin
+            nobody:x:99:99:nobody:/:/usr/bin/nologin
+            EOF
+            chmod 644 ./etc/passwd
+
+            cat <<EOF > ./etc/group
+            root:x:0:root
+            bin:x:1:root,bin,daemon
+            daemon:x:2:root,bin,daemon
+            sys:x:3:root,bin
+            adm:x:4:root,daemon
+            tty:x:5:
+            disk:x:6:root
+            lp:x:7:daemon
+            mem:x:8:
+            kmem:x:9:
+            wheel:x:10:root
+            ftp:x:11:
+            mail:x:12:
+            uucp:x:14:
+            log:x:19:root
+            utmp:x:20:
+            locate:x:21:
+            rfkill:x:24:
+            smmsp:x:25:
+            proc:x:26:
+            http:x:33:
+            games:x:50:
+            lock:x:54:
+            uuidd:x:68:
+            dbus:x:81:
+            network:x:90:
+            video:x:91:
+            audio:x:92:
+            optical:x:93:
+            floppy:x:94:
+            storage:x:95:
+            scanner:x:96:
+            input:x:97:
+            power:x:98:
+            nobody:x:99:
+            EOF
+            chmod 644 ./etc/group
+
+            # get shared libs
+            find . -type f -executable | xargs ldd | awk '{print $3}' | grep -v systemd | sort -u | xargs cp -t usr/lib
+            find . -type f -executable | xargs chmod 755
+
+            # FIXME: hacky patch elf patching. Is there a better way????????
+            find . -type f -executable -print | xargs -I {} ${pkgs.lib.getExe pkgs.patchelf} --set-rpath /lib {} 2> /dev/null
+            find . -type f -executable -print | xargs -I {} ${pkgs.lib.getExe pkgs.patchelf} --set-interpreter /lib/ld-linux-x86-64.so.2 {} 2> /dev/null
+            cp ${self.packages.${system}.glibc.out}/lib/ld-linux-x86-64.so.2 lib/
+            ${pkgs.lib.getExe pkgs.patchelf} --remove-rpath lib/ld-linux-x86-64.so.2
+
+            # gen initrd
+            find . -print0 | ${pkgs.lib.getExe pkgs.cpio} --null --owner=root:root -o --format=newc | ${pkgs.lib.getExe pkgs.gzip} -9 > ../initrd.gz
+          '';
           systemd = pkgs.callPackage ./systemd { };
         };
 
diff --git a/systemd/default.nix b/systemd/default.nix
index 99e4684..a9ae6e8 100644
--- a/systemd/default.nix
+++ b/systemd/default.nix
@@ -137,9 +137,6 @@ stdenv.mkDerivation (finalAttrs: {
 
   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'"
     ''
@@ -150,7 +147,7 @@ stdenv.mkDerivation (finalAttrs: {
         "'${targetPackages.stdenv.cc.bintools.targetPrefix}readelf'" \
         --replace \
         "/usr/lib/systemd/boot/efi" \
-        "$out/lib/systemd/boot/efi"
+        "$out/usr/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
@@ -171,7 +168,7 @@ stdenv.mkDerivation (finalAttrs: {
     "--sysconfdir=/etc"
     "--localstatedir=/var"
     "--libdir=/usr/lib"
-    "--bindir=/bin"
+    "--bindir=/usr/bin"
     "--includedir=/usr/include"
     "--localedir=/usr/share/locale"