Nix/Nixos development

.envrc

@@ -0,0 +1,5 @@
+if ! has nix_direnv_version || ! nix_direnv_version 3.0.6; then
+  source_url "https://raw.githubusercontent.com/nix-community/nix-direnv/3.0.6/direnvrc" "sha256-RYcUJaRMf8oF5LznDrlCXbkOQrywm0HDv1VjYGaJGdM="
+fi
+
+use flake

.gitignore

@@ -15,3 +15,6 @@ lib*.a
 *.iml
 ### macOS ###
 .DS_Store
+
+### direnv ###
+/.direnv/

flake.nix

@@ -0,0 +1,70 @@
+{
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = {
+    self,
+    nixpkgs,
+    flake-utils,
+  }:
+    flake-utils.lib.eachDefaultSystem (system: let
+      pkgs = nixpkgs.legacyPackages.${system};
+      libselinuxPath = with pkgs;
+        lib.makeLibraryPath [
+          libselinux
+        ];
+      libaclPath = with pkgs;
+        lib.makeLibraryPath [
+          acl
+        ];
+
+      build_deps = with pkgs; [
+          clang
+          llvmPackages.bintools
+          rustup
+
+          pre-commit
+
+          # debugging
+          gdb
+        ];
+      gnu_testing_deps = with pkgs; [
+          autoconf
+          automake
+          bison
+          gnum4
+          gperf
+          gettext
+          texinfo
+        ];
+    in {
+      devShell = pkgs.mkShell {
+        buildInputs = build_deps ++ gnu_testing_deps;
+
+        RUSTC_VERSION = "1.75";
+        LIBCLANG_PATH = pkgs.lib.makeLibraryPath [pkgs.llvmPackages_latest.libclang.lib];
+        shellHook = ''
+          export PATH=$PATH:''${CARGO_HOME:-~/.cargo}/bin
+          export PATH=$PATH:''${RUSTUP_HOME:-~/.rustup}/toolchains/$RUSTC_VERSION-x86_64-unknown-linux-gnu/bin/
+        '';
+
+        SELINUX_INCLUDE_DIR = ''${pkgs.libselinux.dev}/include'';
+        SELINUX_LIB_DIR = libselinuxPath;
+        SELINUX_STATIC = "0";
+
+        # Necessary to build GNU.
+        LDFLAGS = ''-L ${libselinuxPath} -L ${libaclPath}'';
+
+        # Add precompiled library to rustc search path
+        RUSTFLAGS =
+          (builtins.map (a: ''-L ${a}/lib'') [
+            ])
+          ++ [
+            ''-L ${libselinuxPath}''
+            ''-L ${libaclPath}''
+          ];
+      };
+    });
+}

util/build-gnu.sh

@@ -371,3 +371,8 @@ sed -i  "s/color_code='0;31;42'/color_code='31;42'/" tests/ls/quote-align.sh
 
 # Slightly different error message
 sed -i 's/not supported/unexpected argument/' tests/mv/mv-exchange.sh
+# Most tests check that `/usr/bin/tr` is working correctly before running.
+# However in NixOS/Nix-based distros, the tr coreutil is located somewhere in
+# /nix/store/xxxxxxxxxxxx...xxxx/bin/tr
+# We just replace the references to `/usr/bin/tr` with the result of `$(which tr)`
+sed -i  's/\/usr\/bin\/tr/$(which tr)/' tests/init.sh