ENT-14460: Added flake to build cfengine locally

.gitignore

@@ -194,3 +194,6 @@ misc/selinux/cfengine-enterprise.pp
 misc/selinux/cfengine-enterprise.if
 misc/selinux/cfengine-enterprise.te
 misc/selinux/tmp
+
+# nix
+contrib/nix/result

contrib/nix/core.nix

@@ -0,0 +1,76 @@
+{ stdenv
+, pkg-config
+, autoreconfHook
+, bison
+, flex
+, diffutils
+, coreutils
+, acl
+, attr
+, curl
+, libxml2
+, libyaml
+, lmdb
+, openssl
+, pcre2
+, zlib
+, librsync
+, pam
+, perl
+, shadow
+, version
+}:
+
+stdenv.mkDerivation {
+  pname = "cfengine-core";
+  version = version;
+  src = ../../.;
+  outputs = [ "out" "buildTree" ];
+
+  postPatch = ''
+    echo "${version}" > CFVERSION
+  '';
+
+  preBuild = ''
+    patchShebangs .
+  '';
+
+  nativeBuildInputs = [
+    pkg-config
+    autoreconfHook
+    bison
+    flex
+    diffutils
+    perl
+    shadow
+  ];
+
+  buildInputs = [
+    acl
+    attr
+    curl
+    libxml2
+    libyaml
+    lmdb
+    openssl
+    pcre2
+    zlib
+    pam
+    librsync
+  ];
+
+  enableParallelBuilding = true;
+
+  configureFlags = [
+    "--with-lmdb"
+    "--enable-debug"
+  ];
+
+  postInstall = ''
+    cp ${coreutils}/bin/date $out/bin/date
+    cp ${diffutils}/bin/diff $out/bin/diffutils
+
+    mkdir -p "$buildTree"
+    cp -a . "$buildTree"/
+  '';
+}

contrib/nix/flake.nix

@@ -0,0 +1,32 @@
+{
+  description = "CFEngine Core";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    self.submodules = true;
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        lib = pkgs.lib;
+
+        baseVersion = lib.strings.trim (builtins.readFile ../../.CFVERSION);
+        shortSha =
+          if self ? rev then builtins.substring 0 9 self.rev
+          else if self ? dirtyRev then builtins.substring 0 9 self.dirtyRev
+          else "unknown0";
+        version = "${baseVersion}a.${shortSha}";
+
+        core = pkgs.callPackage ./core.nix { version = version; };
+      in
+      {
+        packages = {
+          default = core;
+          buildTree = core.buildTree;
+        };
+      }
+    );
+}