symfpu: install headers in $out/include, add a pkg-config file

{ lib, stdenv, fetchFromGitHub }:

{ lib, stdenv, fetchFromGitHub, copyPkgconfigItems, makePkgconfigItem }:

stdenv.mkDerivation rec {

  pname = "symfpu";

    sha256 = "1jf5lkn67q136ppfacw3lsry369v7mdr1rhidzjpbz18jfy9zl9q";

  };

  nativeBuildInputs = [ copyPkgconfigItems ];

  pkgconfigItems = [

    (makePkgconfigItem {

      name = "symfpu";

      inherit version;

      cflags = [ "-I\${includedir}" ];

      variables = {

        includedir = "@includedir@";

      };

      inherit (meta) description;

    })

  ];

  env = {

    # copyPkgconfigItems will substitute this in the pkg-config file

    includedir = "${placeholder "out"}/include";

  };

  installPhase = ''

    mkdir -p $out/symfpu

    cp -r * $out/symfpu/

    runHook preInstall

    mkdir -p $out/include/symfpu

    cp -r * $out/include/symfpu/

    runHook postInstall

  '';

  meta = with lib; {