# Contributor: Lex Black <autumn-wind at web dot de>
# Contributor: Jens Staal <staal1978@gmail.com>

pkgbase=llvmlinux-git
pkgname=${pkgbase}
pkgver=4.3.rc3.r42.g3225031
pkgrel=1
pkgdesc="The Linux Kernel built with (native) LLVM/Clang"
arch=('i686' 'x86_64')
url="http://llvm.linuxfoundation.org/index.php/Main_Page"
license=('GPL2')
depends=('coreutils' 'linux-firmware' 'mkinitcpio')
makedepends=('git' 'quilt' 'llvm' 'clang')
optdepends=('crda: to set the correct wireless channels of your country')
backup=("etc/mkinitcpio.d/${pkgbase}.preset")
install=llvmlinux-git.install
options=(!strip)
#add the source checkouts in sources to avoid having to repeat them.
source=('llvmlinux'::'git://git.linuxfoundation.org/llvmlinux.git'
        'kernel'::'git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git'
        'https://projects.archlinux.org/svntogit/packages.git/snapshot/packages-packages/linux.tar.gz'
        'llvmlinux-git.preset')
md5sums=('SKIP'
         'SKIP'
         '9a24944400fadce1f73539b521366c39'
         '951a65b16527d6f9058bcde1ec2ec158')


export CC=clang
export CXX=clang++
export KARCH=x86
export USE_ARCH_PATCH="yes"

pkgver() {
  cd kernel
  git describe --long | sed 's/\([^-]*-g\)/r\1/;s/-/./g;s/v//'
}

prepare() {
  # ok some hacking needed to get this working...
  ln -s ${srcdir}/kernel ${srcdir}/llvmlinux/arch/all/kernel.git

  ##### Adjust targets #####
  # llvmlinux offers for i586. Arch just provides i686, so does clang
  cd $srcdir/llvmlinux
  mv targets/i586 targets/i686
  mv targets/i686/config_i586 targets/i686/config_i686
  sed -i 's/i586/i686/g' targets/i686/Makefile

  mv arch/i586 arch/i686
  mv arch/i686/i586.mk arch/i686/i686.mk
  sed -i 's/i586/i686/g' arch/i686/i686.mk

  _config=${srcdir}/llvmlinux/targets/${CARCH}/config_${CARCH}

  #Add stuff to the default llvmlinux config
  sed -i 's|# CONFIG_BTRFS_FS is not set|CONFIG_BTRFS_FS=m \n CONFIG_BTRFS_FS_POSIX_ACL=y|g' ${_config}


  _archstuff="${srcdir}/packages-packages/linux/trunk"

  ##### Config #####
  # Using Arch Linux Kernel Config (32-bit or 64-bit. Depending on $CARCH)
  #if [ ${CARCH} == i686 ]; then
  #  cp ${_archstuff}/config ${srcdir}/llvmlinux/targets/${CARCH}/config_${CARCH}
  #else
  #  cp ${_archstuff}/config.x86_64 ${srcdir}/llvmlinux/targets/${CARCH}/config_${CARCH}
  #fi

  # Alternative methods to configure the kernel. Replace the line below with one of your choice.
  cd $srcdir/kernel
  #make menuconfig # CLI menu for configuration
  #make nconfig # new CLI menu for configuration
  #make xconfig # X-based configuration
  #make oldconfig # using old config from previous kernel version
  # ... or manually edit .config

  make localmodconfig

  #Copy generated config to llvm target directory
  cp .config ${srcdir}/llvmlinux/targets/${CARCH}/config_${CARCH}

  # fixing some configuration options
  sed -i 's|CONFIG_LOCALVERSION="-ARCH"|CONFIG_LOCALVERSION="-llvmlinux"|g' ${_config}
  sed -i "s|CONFIG_LOCALVERSION_AUTO=.*|CONFIG_LOCALVERSION_AUTO=n|" ${_config}

  ##### ARCH patch #####
  if [ ${USE_ARCH_PATCH} == yes ]; then
    # patch kernel sources with Arch linux kernel patches
    mkdir ${srcdir}/llvmlinux/targets/${CARCH}/patches/
    cp ${_archstuff}/*.patch ${srcdir}/llvmlinux/targets/${CARCH}/patches/
  fi
}

build() {
  cd llvmlinux/targets/${CARCH}/
  # "native" means distro-installed clang (over 3.3 needed).
  make CLANG_TOOLCHAIN=native kernel-build
}

package() {
  cd llvmlinux/targets/${CARCH}/src/linux

  # don't run depmod on 'make install'. We'll do this ourselves in packaging
  sed -i '2iexit 0' scripts/depmod.sh

  # get kernel version
  _kernver="$(make LOCALVERSION= kernelrelease)"
  _basekernel=${_kernver%%-*}
  _basekernel=${_basekernel%.*}

  mkdir -p "${pkgdir}"/{lib/modules,lib/firmware,boot}
  make LOCALVERSION= INSTALL_MOD_PATH="$pkgdir" modules_install
  cp arch/$KARCH/boot/bzImage "${pkgdir}/boot/vmlinuz-${pkgbase}"

  # add vmlinux
  install -D -m644 vmlinux "${pkgdir}/usr/src/linux-${_kernver}/vmlinux"

  # set correct depmod command for install
  cp -f "${startdir}/${install}" "${startdir}/${install}.pkg"
  true && install=${install}.pkg
  sed \
    -e  "s/KERNEL_NAME=.*/KERNEL_NAME=${_kernelname}/" \
    -e  "s/KERNEL_VERSION=.*/KERNEL_VERSION=${_kernver}/" \
    -i "${startdir}/${install}"

  # install mkinitcpio preset file for kernel
  install -D -m644 "${srcdir}/llvmlinux.preset" "${pkgdir}/etc/mkinitcpio.d/${pkgbase}.preset"
  sed \
    -e "1s|'linux.*'|'${pkgbase}'|" \
    -e "s|ALL_kver=.*|ALL_kver=\"/boot/vmlinuz-${pkgbase}\"|" \
    -e "s|default_image=.*|default_image=\"/boot/initramfs-${pkgbase}.img\"|" \
    -e "s|fallback_image=.*|fallback_image=\"/boot/initramfs-${pkgbase}-fallback.img\"|" \
    -i "${pkgdir}/etc/mkinitcpio.d/${pkgbase}.preset"

  # remove build and source links
  rm -f "${pkgdir}"/lib/modules/${_kernver}/{source,build}
  # remove the firmware
  rm -rf "${pkgdir}/lib/firmware"
  # gzip -9 all modules to save 100MB of space
  find "${pkgdir}" -name '*.ko' -exec gzip -9 {} \;

  # Now we call depmod...
  depmod -b "$pkgdir" -F System.map "$_kernver"

  # move module tree /lib -> /usr/lib
  mv "$pkgdir/lib" "$pkgdir/usr"
}