core/flake.nix

{
  description = "A terminal UI client for the matrix chat protocol";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";

    # inputs for following
    flake-compat = {
      url = "github:edolstra/flake-compat";
      flake = false;
    };
    crane = {
      url = "github:ipetkov/crane";
      inputs = {
        nixpkgs.follows = "nixpkgs";
        flake-compat.follows = "flake-compat";
        flake-utils.follows = "flake-utils";
        rust-overlay.follows = "rust-overlay";
      };
    };
    flake-utils = {
      url = "github:numtide/flake-utils";
      inputs = {};
    };
    rust-overlay = {
      url = "github:oxalica/rust-overlay";
      inputs = {
        nixpkgs.follows = "nixpkgs";
        flake-utils.follows = "flake-utils";
      };
    };

    # cranelift
    rustc_cranelift_backend = {
      url = "github:bjorn3/rustc_codegen_cranelift/dev";
      flake = false;
    };
    rustc_cranelift_backend_src = {
      url = "https://github.com/bjorn3/rustc_codegen_cranelift/releases/download/dev/cg_clif-x86_64-unknown-linux-gnu.tar.xz";
      flake = false;
    };
  };

  outputs = {
    self,
    nixpkgs,
    crane,
    flake-utils,
    rust-overlay,
    rustc_cranelift_backend,
    rustc_cranelift_backend_src,
    ...
  }:
    flake-utils.lib.eachDefaultSystem (system: let
      inherit (pkgs) lib;
      bintools-wrapper = "${nixpkgs}/pkgs/build-support/bintools-wrapper";
      mold' = pkgs.symlinkJoin {
        name = "mold";
        paths = [pkgs.mold];
        nativeBuildInputs = [pkgs.makeWrapper];
        suffixSalt = lib.replaceStrings ["-" "."] ["_" "_"] pkgs.targetPlatform.config;
        postBuild = ''
          for bin in ${pkgs.mold}/bin/*; do
            rm $out/bin/"$(basename "$bin")"

            export prog="$bin"
            substituteAll "${bintools-wrapper}/ld-wrapper.sh" $out/bin/"$(basename "$bin")"
            chmod +x $out/bin/"$(basename "$bin")"

            mkdir -p $out/nix-support
            substituteAll "${bintools-wrapper}/add-flags.sh" $out/nix-support/add-flags.sh
            substituteAll "${bintools-wrapper}/add-hardening.sh" $out/nix-support/add-hardening.sh
            substituteAll "${bintools-wrapper}/../wrapper-common/utils.bash" $out/nix-support/utils.bash
          done
        '';
      };
      c_rust = pkgs.rust-bin.fromRustupToolchainFile "${rustc_cranelift_backend}/rust-toolchain";
      rcb = pkgs.stdenv.mkDerivation {
        pname = "rustc_cranelift_backend";
        version = "1.0";
        buildInputs = [c_rust];
        nativeBuildInputs = with pkgs; [gawk fd];
        srcs = ["${rustc_cranelift_backend_src}" "${c_rust}"];
        sourceRoot = ".";
        postUnpack = ''
          rust_dir="$(fd . --max-depth 1 | awk '!/source/ && !/env-vars/')"

          # remove unneeded stuff
          rm -r "$rust_dir"/{bin,nix-support,share};
          rm -r "$rust_dir"/lib/rustlib/{etc,src,rustc-src};

          cp -r "$rust_dir"/. source/extra_dependencies
          rm -r "$rust_dir"
          cd source
        '';
        postPatch = ''
          # patch bins
          for file in $(fd . --type file);do
              file="$(file --mime "$file" | awk 'BEGIN{FS=":"}/application\/x-pie-executable/{print $1}')";
              if [ "$file" ]; then
                  echo "file: '$file' matches";
                  correct_interpreter_path="$(ldd "$file" | tail -n1 | awk 'BEGIN{FS="=> "} {print $2}' | awk 'BEGIN{FS=" "}{print $1}')"
                  echo "correct interpreter path is: '$correct_interpreter_path'"
                  patchelf --set-interpreter "$correct_interpreter_path" "$file"

                  if [ "$(patchelf --print-interpreter "$file")" = "$correct_interpreter_path" ];then
                    echo "Set interpreter";
                  else
                    echo "Failed to set interprter, the interpreter still is $(patchelf --print-interpreter )";
                    exit 1
                  fi
              fi
          done

          # patch libs
          all_files=$(mktemp);
          for file in $(fd .);do
              canonical_path="$(readlink -f "$file")"
              file="$(file --mime "$canonical_path" | awk 'BEGIN{FS=":"}/application\/x-sharedlib/{print $1}')";
              if [ "$file" ]; then
                  echo "$file" >> $all_files;
              fi
          done
          while read -r file; do
              echo "___________________";
              echo "Checking file: '$file'";
              is_missing="$(ldd "$file" | awk 'BEGIN{FS="=>"}{if (/not found/){print $1}}')"
              if [ "$is_missing" ];then
                  echo "Warning: The following things are missing:";
                  for line in $is_missing; do
                      echo "  $line";
                  done
                  echo
                  for line in $is_missing; do
                      echo "Searching for a substitute for '$line'"
                      substitute="$(grep "$line" "$all_files" | awk 'BEGIN{FS=" "}{print $1}' | tail -n1)";
                      if [ "$substitute" ]; then
                          echo "Found '$substitute', which can substitute '$line'"
                          echo "Patching.."
                          patchelf --replace-needed "$line" "$(readlink -f "$substitute")" "$file";
                      else
                          echo "Error: Failed to find a substitute"
                      fi
                  done
              else
                  echo "This file is not missing anything"
              fi
          done < $all_files
          rm $all_files
        '';
        installPhase = ''
          install -d $out/
          cp -r ./. $out/
        '';
      };
      pkgs = import nixpkgs {
        inherit system;
        overlays = [(import rust-overlay)];
      };

      nightly = false;
      rust =
        if nightly
        then pkgs.rust-bin.selectLatestNightlyWith (toolchain: toolchain.default)
        else pkgs.rust-bin.stable.latest.default;

      craneLib = (crane.mkLib pkgs).overrideToolchain rust;

      nativeBuildInputs = with pkgs; [
        pkg-config
        mold'
        rcb
      ];
      buildInputs = with pkgs; [
        openssl
        lua54Packages.lua
      ];

      craneBuild = craneLib.buildPackage {
        src = craneLib.cleanCargoSource ./.;

        doCheck = true;
        inherit nativeBuildInputs buildInputs;
      };
    in {
      packages = {
        default = craneBuild;
      };

      app.default = {
        type = "app";
        program = "${self.packages.${system}.default}/bin/trinitix";
      };

      devShells.default = pkgs.mkShell {
        packages = with pkgs; [
          nil
          alejandra
          statix
          ltex-ls

          rust
          rust-analyzer
          cargo-edit
          cargo-expand
        ];
        inherit nativeBuildInputs buildInputs;
      };
    });
}
# vim: ts=2