# Maintainer: Joan Figueras <ffigue at gmail dot com>
# Contributor: Torge Matthies <openglfreak at googlemail dot com>
# Contributor: Jan Alexander Steffens (heftig) <jan.steffens@gmail.com>
# Contributor: Yoshi2889 <rick.2889 at gmail dot com>
# Contributor: Tobias Powalowski <tpowa@archlinux.org>
# Contributor: Thomas Baechler <thomas@archlinux.org>

##
## The following variables can be customized at build time. Use env or export to change at your wish
##
##   Example: env _microarchitecture=25 use_numa=n use_tracers=n use_pds=n makepkg -sc
##
## Look inside 'choose-gcc-optimization.sh' to choose your microarchitecture
## Valid numbers between: 0 to 25
## Default is: 0 => generic
## Good option if your package is for one machine: 25 => native
if [ -z ${_microarchitecture+x} ]; then
  _microarchitecture=0
fi
##
## Disable NUMA since most users do not have multiple processors. Breaks CUDA/NvEnc.
## Archlinux and Xanmod enable it by default.
## Set variable "use_numa" to: n to disable (possibly increase performance)
##                             y to enable  (stock default)
if [ -z ${use_numa+x} ]; then
  use_numa=y
fi
##
## For performance you can disable FUNCTION_TRACER/GRAPH_TRACER. Limits debugging and analyzing of the kernel.
## Stock Archlinux and Xanmod have this enabled. 
## Set variable "use_tracers" to: n to disable (possibly increase performance)
##                                y to enable  (stock default)
if [ -z ${use_tracers+x} ]; then
  use_tracers=y
fi
##
## Enable PDS CPU scheduler by default https://gitlab.com/alfredchen/linux-pds
## Set variable "use_pds" to: n to disable (stock Xanmod)
##                            y to enable
if [ -z ${use_pds+x} ]; then
  use_pds=n
fi

pkgbase=linux-xanmod
_srcname=linux
pkgver=5.3.5
xanmod=4
pkgrel=1
arch=(x86_64)
url="http://www.xanmod.org/"
license=(GPL2)
makedepends=(
  xmlto kmod inetutils bc libelf git python-sphinx python-sphinx_rtd_theme
  graphviz imagemagick cpio
)
options=('!strip')
_srcname="linux-${pkgver}-xanmod${xanmod}"

source=(https://github.com/xanmod/linux/archive/${pkgver}-xanmod${xanmod}.tar.gz
       60-linux.hook  # pacman hook for depmod
       90-linux.hook  # pacman hook for initramfs regeneration
       ${pkgbase}.preset   # standard config files for mkinitcpio ramdisk
       choose-gcc-optimization.sh
       0001-add-sysctl-to-disallow-unprivileged-CLONE_NEWUSER-by.patch  # Grabbed from linux-ck package
)

sha256sums=('22d008af13323f0893c6146311d4a09f8cc0d12a02958a4056bb8e3024221a81'
            'ae2e95db94ef7176207c690224169594d49445e04249d2499e9d2fbc117a0b21'
            'c043f3033bb781e2688794a59f6d1f7ed49ef9b13eb77ff9a425df33a244a636'
            'ad6344badc91ad0630caacde83f7f9b97276f80d26a20619a87952be65492c65'
            '8b2629f6340d4807c113cd9fa308f50f0a8d85df5698bef083e151f06d58f748'
            '112b16c247dae8ff44066fd0268012f9c623d5da349ebd66896e54257b3404a5')

_kernelname=${pkgbase#linux}

prepare() {
  cd $_srcname

  # Workaround GCC 9 build, source: https://www.linuxquestions.org/questions/slackware-14/make-linux-4-19-42-error-4175653720/
  export LANG=en_US.UTF-8

  msg2 "Setting version..."
  scripts/setlocalversion --save-scmversion
  echo "-$pkgrel" > localversion.10-pkgrel
  echo "$_kernelname" > localversion.20-pkgname

  # Archlinux patches
  local src
  for src in "${source[@]}"; do
    src="${src%%::*}"
    src="${src##*/}"
    [[ $src = *.patch ]] || continue
    msg2 "Applying patch $src..."
    patch -Np1 < "../$src"
  done

  # CONFIG_STACK_VALIDATION gives better stack traces. Also is enabled in all official kernel packages by Archlinux team
  scripts/config --enable CONFIG_STACK_VALIDATION

  # Enable IKCONFIG following Arch's philosophy
  scripts/config --enable CONFIG_IKCONFIG \
                 --enable CONFIG_IKCONFIG_PROC

  # User set. See at the top of this file
  if [ "$use_tracers" = "n" ]; then
    msg2 "Disabling FUNCTION_TRACER/GRAPH_TRACER..."
    scripts/config --disable CONFIG_FUNCTION_TRACER \
                   --disable CONFIG_STACK_TRACER
  fi

  if [ "$use_numa" = "n" ]; then
    msg2 "Disabling NUMA..."
    scripts/config --disable CONFIG_NUMA
  fi

  if [ "$use_pds" = "y" ]; then
    msg2 "Enabling PDS CPU scheduler by default..."
    scripts/config --enable CONFIG_SCHED_PDS
  fi

  # Let's user choose microarchitecture optimization in GCC
  ${srcdir}/choose-gcc-optimization.sh $_microarchitecture

  # This is intended for the people that want to build this package with their own config
  # Put the file "myconfig" at the package folder to use this feature
  if [ -f "${startdir}/myconfig" ]; then
    msg2 "Using user CUSTOM config..."
    cp -f "${startdir}"/myconfig .config
  fi

  make olddefconfig

  make -s kernelrelease > ../version
  msg2 "Prepared %s version %s" "$pkgbase" "$(<../version)"
}

build() {
  cd $_srcname
  make bzImage modules
}

_package() {
  pkgdesc="The Linux kernel and modules with Xanmod patches"
  depends=(coreutils linux-firmware kmod mkinitcpio)
  optdepends=('crda: to set the correct wireless channels of your country')
  provides=('linux' 'linux-xanmod-git')
  replaces=('linux-xanmod-git')
  conflicts=('linux-xanmod-git')
  backup=("etc/mkinitcpio.d/$pkgbase.preset")
  install=linux.install

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

  cd $_srcname

  msg2 "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"
  install -Dm644 "$modulesdir/vmlinuz" "$pkgdir/boot/vmlinuz-$pkgbase"

  msg2 "Installing modules..."
  make INSTALL_MOD_PATH="$pkgdir/usr" 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 "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 "$subst" ../$pkgbase.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-headers() {
  pkgdesc="Header files and scripts for building modules for Xanmod Linux kernel"
  provides=('linux-headers' 'linux-xanmod-git-headers')
  replaces=('linux-xanmod-git-headers')
  conflicts=('linux-xanmod-git-headers')

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

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

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

# vim:set ts=8 sts=2 sw=2 et: