# Maintainer: jc_gargma <jc_gargma@iserlohn-fortress.net>
# Maintainer (Arch): Jan Alexander Steffens (heftig) <heftig@archlinux.org>
# Contributor: Aqua-sama <aqua@iserlohn-fortress.net>

# # I maintain this because:
# Arch version patch script does not apply consistently
# Arch version lacks graysky gcc patch
# Arch version lacks ath9k regdom and raid6 algo patches
# Arch version is 300 Hz
# Arch version does not disable lockdown eee
# Arch version does not disable hdcp
# Arch version uses git

pkgbase=linux
_supver=5
_majver=8
_minver=13
_gccpatchver='20200615'
_gccpatchger='10.1'
_gccpatchker='5.8'
  if [ "$_minver" == "0" ]; then
    pkgver=${_supver}.${_majver}
  else
    pkgver=${_supver}.${_majver}.${_minver}
  fi
pkgrel=1
pkgdesc='Linux'
url='https://kernel.org'
arch=(x86_64)
license=(GPL2)
makedepends=(
  bc kmod libelf pahole
  xmlto python-sphinx python-sphinx_rtd_theme graphviz imagemagick
)
conflicts=('linux-libre')
options=('!strip')
_srcname=linux-${pkgver}
source=(
  https://www.kernel.org/pub/linux/kernel/v${_supver}.x/${_srcname}.tar.{xz,sign}
  0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
  0002-virt-vbox-Add-support-for-the-new-VBG_IOCTL_ACQUIRE_.patch
  kernel_gcc_patch-${_gccpatchver}.tar.gz::https://github.com/graysky2/kernel_gcc_patch/archive/${_gccpatchver}.tar.gz
  ath9k-regdom-hack.patch
  raid6-default-algo.patch
  config         # the main kernel config file
  sphinx-workaround.patch
)
validpgpkeys=(
  'ABAF11C65A2970B130ABE3C479BE3E4300411886'  # Linus Torvalds
  '647F28654894E3BD457199BE38DBBDC86092693E'  # Greg Kroah-Hartman
)
# https://www.kernel.org/pub/linux/kernel/v5.x/sha256sums.asc
b2sums=('1b3510440d07032fd38beec3f325fee6cde73ba07f2fa4d0e220c3d86069a21852a9dd16cdb993a714c12eee2a3eff02f13504326f83354126f02ee399205d92'
        'SKIP'
        'dd8d62b88c0d79eb18b5695b39ca374657b5dd3f5c296a9b262b98e8d0058709b52ad4b56e69afe2fa3db25f944636b8b1eec951e40bd5d02b4127dde6cc4796'
        'e54020096951d8e1adb06f524259238fe56922f535f44645d30e4645ac0cb53264afc4840ff77052e3fe8bea4d1a5199d5909041596f0fdfa60203f3ef34248c'
        'c8d0697f99fe6105815217b8ec059d8f587415ea8dd2b88a65e1087feedf697341a64cd56810fde9e7aeada79125fc8235faccc7e7b06492c099e27a8abbe99c'
        '2e58bb89b247b1678355368956e67c1de51fcde97a227b2162f6771e30f17fa5520faafe7be4b6816a542e7ae10d05f64c6b6354f352c12746d4b8da632936dd'
        'fde132f3705d908e6f2147c78a2193289916d72304ca5efa2229d79fc3e57a857314ce94e71425caef2f7f7b6cf87f05ef86335dc8bd4be78e7035afe608005a'
        '5c62c85088abb1312f1cc2aafdcc140ebe7beb93a1be86cf2e1bc88f8256c31cac955c0f03377da9855c4949479d209d93497a4fc05789637a4d3ad31ab5705b'
        'b4e1377d97ad7e8144d6e55b6d43731e3271a5aec65b65ca6d81026a95f15f549b9303fb3c6f492099ca691e3f65f4cf7f0c3aa742df03b396d7f6d81813aa95')

export KBUILD_BUILD_HOST=arc4linux
export KBUILD_BUILD_USER=$pkgbase
export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

prepare() {
  cd $_srcname

  # add upstream patch
#  if [ "$_minver" != "0" ]; then
#    echo "Applying upstream patch"
#    patch -Np1 < ../patch-${_supver}.${_majver}-${pkgver}
#  fi


  # Hotfixes
  echo "Applying hotfixes"
  patch -p1 -i ../0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
  patch -p1 -i ../0002-virt-vbox-Add-support-for-the-new-VBG_IOCTL_ACQUIRE_.patch
  patch -p1 -i ../sphinx-workaround.patch


  # graysky gcc patch
  echo "Applying graysky cpu patch"
  patch -p1 -i ../kernel_gcc_patch-${_gccpatchver}/enable_additional_cpu_optimizations_for_gcc_v${_gccpatchger}+_kernel_v${_gccpatchker}+.patch


  # Ignore ath9k eeprom patch
  echo "Applying ath9k patch"
  patch -p1 -i ../ath9k-regdom-hack.patch

  # Set default raid6 algo patch
  echo " Applying raid6 patch"
  patch -p1 -i ../raid6-default-algo.patch


  echo "Setting version..."
  scripts/setlocalversion --save-scmversion
  echo "-$pkgrel" > localversion.10-pkgrel
  echo "${pkgbase#linux}" > localversion.20-pkgname


  echo "Setting config..."
  # we are in src/linux-x.yy.zz, looking for a config next to the pkgbuild
#  if [ -f ${SRCDEST}/config.previous ]; then
#    cp ${SRCDEST}/config.previous .config
#  else
    cp ../config .config
#  fi

  make olddefconfig

#  make menuconfig

  # Remove sublevel when no sublevel exists
  if [ "$_minver" == "0" ]; then
    sed -i '/SUBLEVEL = 0/d' Makefile
  fi

  make -s kernelrelease > version

  # workaround for make -s kernelrelease not applying
  # localversion to version when changed using menuconfig
  grep -Po '(?<=CONFIG_LOCALVERSION=").*(?=")' .config > ../localversion
  echo "$pkgver" > ../version.temp
  cat "localversion.10-pkgrel" >> ../version.temp
  cat "localversion.20-pkgname" >> ../version.temp
  cat ../localversion >> ../version.temp
  cat ../version.temp | tr -d "\n" > version

  # back up the config
#  echo "Backing up config..."
#  cp .config ${SRCDEST}/config.previous

  echo "Prepared $pkgbase version $(<version)"
}

build() {
  cd $_srcname
  make all
  make htmldocs
}

_package() {
  pkgdesc="The $pkgdesc kernel and modules"
  depends=(coreutils kmod initramfs)
  optdepends=('crda: to set the correct wireless channels of your country'
              'linux-firmware: firmware images needed for some devices')
  provides=(VIRTUALBOX-GUEST-MODULES WIREGUARD-MODULE)
  replaces=(virtualbox-guest-modules-arch wireguard-arch)

  cd $_srcname
  local kernver="$(<version)"
  local modulesdir="$pkgdir/usr/lib/modules/$kernver"

  echo "Installing boot image..."
  # systemd expects to find the kernel here to allow hibernation
  # https://github.com/systemd/systemd/commit/edda44605f06a41fb86b7ab8128dcf99161d2344
  install -Dm644 "$(make -s image_name)" "$modulesdir/vmlinuz"

  # Used by mkinitcpio to name the kernel
  echo "$pkgbase" | install -Dm644 /dev/stdin "$modulesdir/pkgbase"

  echo "Installing modules..."
  make INSTALL_MOD_PATH="$pkgdir/usr" INSTALL_MOD_STRIP=1 modules_install

  # remove build and source links
  rm "$modulesdir"/{source,build}
}

_package-headers() {
  pkgdesc="Headers and scripts for building modules for the $pkgdesc kernel"

  cd $_srcname
  local builddir="$pkgdir/usr/lib/modules/$(<version)/build"

  echo "Installing build files..."
  install -Dt "$builddir" -m644 .config Makefile Module.symvers System.map \
    localversion.* version vmlinux
  install -Dt "$builddir/kernel" -m644 kernel/Makefile
  install -Dt "$builddir/arch/x86" -m644 arch/x86/Makefile
  cp --reflink -t "$builddir" -a scripts

  # add objtool for external module building and enabled VALIDATION_STACK option
  if [[ -e tools/objtool/objtool ]]; then
    install -Dt "$builddir/tools/objtool" tools/objtool/objtool
  fi

  # add xfs and shmem for aufs building
  mkdir -p "$builddir"/{fs/xfs,mm}

  echo "Installing headers..."
  cp --reflink -t "$builddir" -a include
  cp --reflink -t "$builddir/arch/x86" -a arch/x86/include
  install -Dt "$builddir/arch/x86/kernel" -m644 arch/x86/kernel/asm-offsets.s

  install -Dt "$builddir/drivers/md" -m644 drivers/md/*.h
  install -Dt "$builddir/net/mac80211" -m644 net/mac80211/*.h

  # http://bugs.archlinux.org/task/13146
  install -Dt "$builddir/drivers/media/i2c" -m644 drivers/media/i2c/msp3400-driver.h

  # http://bugs.archlinux.org/task/20402
  install -Dt "$builddir/drivers/media/usb/dvb-usb" -m644 drivers/media/usb/dvb-usb/*.h
  install -Dt "$builddir/drivers/media/dvb-frontends" -m644 drivers/media/dvb-frontends/*.h
  install -Dt "$builddir/drivers/media/tuners" -m644 drivers/media/tuners/*.h

  echo "Installing KConfig files..."
  find . -name 'Kconfig*' -exec install -Dm644 {} "$builddir/{}" \;

  echo "Removing unneeded architectures..."
  local arch
  for arch in "$builddir"/arch/*/; do
    [[ $arch = */x86/ ]] && continue
    echo "Removing $(basename "$arch")"
    rm -r "$arch"
  done

  echo "Removing documentation..."
  rm -r "$builddir/Documentation"

  echo "Removing broken symlinks..."
  find -L "$builddir" -type l -printf 'Removing %P\n' -delete

  echo "Removing loose objects..."
  find "$builddir" -type f -name '*.o' -printf 'Removing %P\n' -delete

  echo "Stripping build tools..."
  local file
  while read -rd '' file; do
    case "$(file -bi "$file")" in
      application/x-sharedlib\;*)      # Libraries (.so)
        strip -v $STRIP_SHARED "$file" ;;
      application/x-archive\;*)        # Libraries (.a)
        strip -v $STRIP_STATIC "$file" ;;
      application/x-executable\;*)     # Binaries
        strip -v $STRIP_BINARIES "$file" ;;
      application/x-pie-executable\;*) # Relocatable binaries
        strip -v $STRIP_SHARED "$file" ;;
    esac
  done < <(find "$builddir" -type f -perm -u+x ! -name vmlinux -print0)

  echo "Stripping vmlinux..."
  strip -v $STRIP_STATIC "$builddir/vmlinux"

  echo "Adding symlink..."
  mkdir -p "$pkgdir/usr/src"
  ln -sr "$builddir" "$pkgdir/usr/src/$pkgbase"
}

_package-docs() {
  pkgdesc="Documentation for the $pkgdesc kernel"

  cd $_srcname
  local builddir="$pkgdir/usr/lib/modules/$(<version)/build"

  echo "Installing documentation..."
  local src dst
  while read -rd '' src; do
    dst="${src#Documentation/}"
    dst="$builddir/Documentation/${dst#output/}"
    install -Dm644 "$src" "$dst"
  done < <(find Documentation -name '.*' -prune -o ! -type d -print0)

  echo "Adding symlink..."
  mkdir -p "$pkgdir/usr/share/doc"
  ln -sr "$builddir/Documentation" "$pkgdir/usr/share/doc/$pkgbase"
}

pkgname=("$pkgbase" "$pkgbase-headers" "$pkgbase-docs")
for _p in "${pkgname[@]}"; do
  eval "package_$_p() {
    $(declare -f "_package${_p#$pkgbase}")
    _package${_p#$pkgbase}
  }"
done