pkgbase=linux
pkgname=('linux' 'linux-headers' 'linux-docs')
pkgver=4.18.5
_srcname=linux-$pkgver
pkgrel=1
arch=('x86_64')
url="https://www.kernel.org/"
license=('GPL2')
makedepends=('xmlto' 'kmod' 'inetutils' 'bc' 'libelf')
options=('!strip')
source=(
  https://www.kernel.org/pub/linux/kernel/v4.x/${_srcname}.tar.{xz,sign}
  config.x86_64  # the main kernel config file
  60-linux.hook  # pacman hook for depmod
  90-linux.hook  # pacman hook for initramfs regeneration
  linux.preset   # standard config files for mkinitcpio ramdisk
)
validpgpkeys=(
  'ABAF11C65A2970B130ABE3C479BE3E4300411886'  # Linus Torvalds
  '647F28654894E3BD457199BE38DBBDC86092693E'  # Greg Kroah-Hartman
  '8218F88849AAC522E94CF470A5E9288C4FA415FA'  # Jan Alexander Steffens (heftig)
)
sha256sums=('fb090a3680eddf6f10bf895bc3075bd3f830e3d2429ce469982db5a28df647bd'
            'SKIP'
            'a7036446f02aab501936933d453f3a99c84904b9ad88ea662eb9618972abebf3'
            'ae2e95db94ef7176207c690224169594d49445e04249d2499e9d2fbc117a0b21'
            '75f99f5239e03238f88d1a834c50043ec32b1dc568f2cc291b07d04718483919'
            'ad6344badc91ad0630caacde83f7f9b97276f80d26a20619a87952be65492c65')

_kernelname=-CHAKRA

prepare() {
  cd ${_srcname}

  # add latest fixes from stable queue, if needed
  # http://git.kernel.org/?p=linux/kernel/git/stable/stable-queue.git

  cat ../config.x86_64 - >.config <<END
CONFIG_LOCALVERSION="${_kernelname}"
CONFIG_LOCALVERSION_AUTO=n
END

  # set extraversion to pkgrel and empty localversion
  sed -e "/^EXTRAVERSION =/s/=.*/= -${pkgrel}/" \
      -e "/^EXTRAVERSION =/aLOCALVERSION =" \
      -i Makefile

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

  # get kernel version
  make prepare
  make -s kernelrelease > ../version

  # load configuration
  # Configure the kernel. Replace the line below with one of your choice.
  #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

  # rewrite configuration
  yes "" | make config >/dev/null

  # save configuration for later reuse
  cat .config > "${startdir}/config.x86_64.last"
}

build() {
  cd ${_srcname}

  make ${MAKEFLAGS} bzImage modules
}

package_linux() {
  pkgdesc="The Linux Kernel and modules"
  groups=('base')
  depends=('coreutils' 'linux-firmware' 'kmod' 'mkinitcpio>=0.7')
  optdepends=('crda: to set the correct wireless channels of your country')
  backup=("etc/mkinitcpio.d/${pkgbase}.preset")
  install=linux.install

  local kernver="$(<version)"
  
  cd ${_srcname}

  msg2 "Installing boot image..."
  install -Dm644 "$(make -s image_name)" "$pkgdir/boot/vmlinuz-$pkgbase"

  msg2 "Installing modules..."
  local modulesdir="$pkgdir/usr/lib/modules/$kernver"
  mkdir -p "$modulesdir"
  make INSTALL_MOD_PATH="$pkgdir/usr" DEPMOD=/doesnt/exist modules_install

  # a place for external modules,
  # with version file for building modules and running depmod from hook
  local extramodules="extramodules$_kernelname"
  local extradir="$pkgdir/usr/lib/modules/$extramodules"
  install -Dt "$extradir" -m644 ../version
  ln -sr "$extradir" "$modulesdir/extramodules"

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

  msg2 "Running depmod..."
  depmod -b "$pkgdir/usr" -E Module.symvers -e "$kernver"

  msg2 "Installing hooks..."

  # sed expression for following substitutions
  local subst="
    s|%PKGBASE%|$pkgbase|g
    s|%KERNVER%|$kernver|g
    s|%EXTRAMODULES%|$extramodules|g
  "

  # hack to allow specifying an initially nonexisting install file
  sed "$subst" "$startdir/$install" > "$startdir/$install.pkg"
  true && install=$install.pkg

  # fill in mkinitcpio preset and pacman hooks
  sed "$subst" ../linux.preset | install -Dm644 /dev/stdin \
    "$pkgdir/etc/mkinitcpio.d/$pkgbase.preset"
  sed "$subst" ../60-linux.hook | install -Dm644 /dev/stdin \
    "$pkgdir/usr/share/libalpm/hooks/60-$pkgbase.hook"
  sed "$subst" ../90-linux.hook | install -Dm644 /dev/stdin \
    "$pkgdir/usr/share/libalpm/hooks/90-$pkgbase.hook"

  msg2 "Fixing permissions..."
  chmod -Rc u=rwX,go=rX "$pkgdir"
}

package_linux-headers() {
  pkgdesc="Header files and scripts for building modules for ${pkgbase/linux/Linux} kernel"

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

  cd $_srcname

  msg2 "Installing build files..."
  install -Dt "$builddir" -m644 Makefile .config Module.symvers System.map vmlinux
  install -Dt "$builddir/kernel" -m644 kernel/Makefile
  install -Dt "$builddir/arch/x86" -m644 arch/x86/Makefile
  cp -t "$builddir" -a scripts

  # add objtool for external module building and enabled VALIDATION_STACK option
  install -Dt "$builddir/tools/objtool" tools/objtool/objtool

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

  # ???
  mkdir "$builddir/.tmp_versions"

  msg2 "Installing headers..."
  cp -t "$builddir" -a include
  cp -t "$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

  msg2 "Installing KConfig files..."
  find . -name 'Kconfig*' -exec install -Dm644 {} "$builddir/{}" \;

  msg2 "Removing unneeded architectures..."
  local arch
  for arch in "$builddir"/arch/*/; do
    [[ $arch = */x86/ ]] && continue
    echo "Removing $(basename "$arch")"
    rm -r "$arch"
  done

  msg2 "Removing documentation..."
  rm -r "$builddir/Documentation"

  msg2 "Removing broken symlinks..."
  find -L "$builddir" -type l -printf 'Removing %P\n' -delete

  msg2 "Removing loose objects..."
  find "$builddir" -type f -name '*.o' -printf 'Removing %P\n' -delete

  msg2 "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)

  msg2 "Fixing permissions..."
  chmod -Rc u=rwX,go=rX "$pkgdir"
}

package_linux-docs() {
  pkgdesc="Kernel hackers manual - HTML documentation that comes with the ${pkgbase/linux/Linux} kernel"

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

  cd $_srcname

  msg2 "Installing documentation..."
  mkdir -p "$builddir"
  cp -t "$builddir" -a Documentation

  msg2 "Fixing permissions..."
  chmod -Rc u=rwX,go=rX "$pkgdir"
}