{ fetchurl, stdenv, flex, bison, gettext, ncurses, libusb, freetype, qemu
, devicemapper, EFIsupport ? false }:

let

  prefix = "grub${if EFIsupport then "-efi" else ""}";

  version = "2.00";

  unifont_bdf = fetchurl {
    url = "http://unifoundry.com/unifont-5.1.20080820.bdf.gz";
    sha256 = "0s0qfff6n6282q28nwwblp5x295zd6n71kl43xj40vgvdqxv0fxx";
  };

in

stdenv.mkDerivation rec {
  name = "${prefix}-${version}";

  src = fetchurl {
    url = "mirror://gnu/grub/grub-${version}.tar.xz";
    sha256 = "0n64hpmsccvicagvr0c6v0kgp2yw0kgnd3jvsyd26cnwgs7c6kkq";
  };

  buildNativeInputs = [ flex bison ];
  buildInputs = [ ncurses libusb freetype gettext devicemapper ]
    ++ stdenv.lib.optional doCheck qemu;

  preConfigure =
    '' for i in "tests/util/"*.in
       do
         sed -i "$i" -e's|/bin/bash|/bin/sh|g'
       done

       # Apparently, the QEMU executable is no longer called
       # `qemu-system-i386', even on i386.
       #
       # In addition, use `-nodefaults' to avoid errors like:
       #
       #  chardev: opening backend "stdio" failed
       #  qemu: could not open serial device 'stdio': Invalid argument
       #
       # See <http://www.mail-archive.com/qemu-devel@nongnu.org/msg22775.html>.
       sed -i "tests/util/grub-shell.in" \
           -e's/qemu-system-i386/qemu-system-x86_64 -nodefaults/g'

       # Fix for building on Glibc 2.16.  Won't be needed once the
       # gnulib in grub is updated.
       sed -i '/gets is a security hole/d' grub-core/gnulib/stdio.in.h
    '';

  # Source code generated by bison 2.6.4 contains pragmas that trigger
  # warnings when built with -Wunknown-pragmas. Since Grub compiles with
  # -Werror, this causes the build to fail. We work around this issue by
  # ignoring pragma-related warnings, but clearly it would be better if
  # Bison wouldn't trigger that issue in the first place. A bug report
  # has been sent.
  prePatch =
    '' gunzip < "${unifont_bdf}" > "unifont.bdf"
       sed -i "configure" \
           -e "s|/usr/src/unifont.bdf|$PWD/unifont.bdf|g" \
           -e "s|-Wunknown-pragmas|-Wno-pragmas|g"
    '';

  configureFlags =
    let arch = if stdenv.system == "i686-linux" then "i386"
               else if stdenv.system == "x86_64-linux" then "x86_64"
               else throw "unsupported EFI firmware architecture";
    in
      stdenv.lib.optionals EFIsupport
        [ "--with-platform=efi" "--target=${arch}" "--program-prefix=" ];

  doCheck = false;
  enableParallelBuilding = true;

  meta = {
    description = "GNU GRUB, the Grand Unified Boot Loader (2.x beta)";

    longDescription =
      '' GNU GRUB is a Multiboot boot loader. It was derived from GRUB, GRand
         Unified Bootloader, which was originally designed and implemented by
         Erich Stefan Boleyn.

         Briefly, the boot loader is the first software program that runs when a
         computer starts.  It is responsible for loading and transferring
         control to the operating system kernel software (such as the Hurd or
         the Linux).  The kernel, in turn, initializes the rest of the
         operating system (e.g., GNU).
      '';

    homepage = http://www.gnu.org/software/grub/;

    license = "GPLv3+";

    maintainers = with stdenv.lib.maintainers; [ ludo shlevy ];

    platforms = if EFIsupport then
      [ "i686-linux" "x86_64-linux" ]
    else
      stdenv.lib.platforms.gnu;
  };
}