# 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>

##
## The following variables can be customized at build time. Use env or export to change at your wish
##
##   Example: env _microarchitecture=98 use_numa=n use_tracers=n makepkg -sc
##
## Look inside 'choose-gcc-optimization.sh' to choose your microarchitecture
## Valid numbers between: 0 to 99
## Default is: 0 => generic
## Good option if your package is for one machine: 98 (Intel native) or 99 (AMD 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

## GCC is the unique compiler supported
if [ -z ${_compiler+x} ]; then
  _compiler=gcc
fi

# Compress modules with ZSTD (to save disk space)
if [ -z ${_compress_modules+x} ]; then
  _compress_modules=n
fi

# Compile ONLY used modules to VASTLY reduce the number of modules built
# and the build time.
#
# To keep track of which modules are needed for your specific system/hardware,
# give module_db script a try: https://aur.archlinux.org/packages/modprobed-db
# This PKGBUILD read the database kept if it exists
#
# More at this wiki page ---> https://wiki.archlinux.org/index.php/Modprobed-db
if [ -z ${_localmodcfg} ]; then
  _localmodcfg=n
fi

# Tweak kernel options prior to a build via nconfig
if [ -z ${_makenconfig} ]; then
  _makenconfig=n
fi

### IMPORTANT: Do no edit below this line unless you know what you're doing

pkgbase=linux-xanmod-rt510
_major=5.10
pkgver=${_major}.131
_branch=5.x
_rt=72
xanmod=1
pkgrel=${xanmod}.${_rt}
pkgdesc='Linux Xanmod real-time version'
url="http://www.xanmod.org/"
arch=(x86_64)
license=(GPL2)
makedepends=(
  bc cpio kmod libelf perl tar xz
)
options=('!strip')
_srcname="linux-${pkgver}-rt${_rt}-xanmod${xanmod}"

source=("https://cdn.kernel.org/pub/linux/kernel/v${_branch}/linux-${_major}.tar."{xz,sign}
        "https://github.com/xanmod/linux/releases/download/${pkgver}-rt${_rt}-xanmod${xanmod}/patch-${pkgver}-rt${_rt}-xanmod${xanmod}.xz"
        choose-gcc-optimization.sh)
validpgpkeys=(
    'ABAF11C65A2970B130ABE3C479BE3E4300411886' # Linux Torvalds
    '647F28654894E3BD457199BE38DBBDC86092693E' # Greg Kroah-Hartman
)

# Archlinux patches
_commit="ec9e9a4219fe221dec93fa16fddbe44a34933d8d"
_patches=()
for _patch in ${_patches[@]}; do
    #source+=("${_patch}::https://git.archlinux.org/svntogit/packages.git/plain/trunk/${_patch}?h=packages/linux&id=${_commit}")
    source+=("${_patch}::https://raw.githubusercontent.com/archlinux/svntogit-packages/${_commit}/trunk/${_patch}")
done

sha256sums=('dcdf99e43e98330d925016985bfbc7b83c66d367b714b2de0cbbfcbf83d8ca43'
            'SKIP'
            'ed536019466c3dfba8302455d2a85da2568a678d8a6b34edfedb0cbf3d1de9b1'
            '51742dee57cd15bece152d6527f48af87cb7930f0f6a356d5282f778e7c35b39')

export KBUILD_BUILD_HOST=${KBUILD_BUILD_HOST:-archlinux}
export KBUILD_BUILD_USER=${KBUILD_BUILD_USER:-makepkg}
export KBUILD_BUILD_TIMESTAMP=${KBUILD_BUILD_TIMESTAMP:-$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})}

prepare() {
  cd linux-${_major}

  # Apply Xanmod patch
  patch -Np1 -i ../patch-${pkgver}-rt${_rt}-xanmod${xanmod}

  msg2 "Setting version..."
  scripts/setlocalversion --save-scmversion
  echo "-$pkgrel" > localversion.10-pkgrel
  #echo "${pkgbase#linux-xanmod}" > 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

  # Applying configuration
  cp -vf CONFIGS/xanmod/${_compiler}/config .config

  # 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

  # Compress modules by default (following Arch's kernel)
  if [ "$_compress_modules" = "y" ]; then
    scripts/config --enable CONFIG_MODULE_COMPRESS_ZSTD
  fi

  # Let's user choose microarchitecture optimization in GCC
  ../choose-gcc-optimization.sh $_microarchitecture
  # Disable CONFIG_GENERIC_CPU2 if we have choosen another microarchitecture
  # https://github.com/xanmod/linux/issues/240
  [ "$_microarchitecture" = "0" ] || scripts/config --disable CONFIG_GENERIC_CPU2

  # This is intended for the people that want to build this package with their own config
  # Put the file "myconfig" at the package folder (this will take preference) or "${XDG_CONFIG_HOME}/linux-xanmod/myconfig"
  # If we detect partial file with scripts/config commands, we execute as a script
  # If not, it's a full config, will be replaced
  for _myconfig in "${SRCDEST}/myconfig" "${HOME}/.config/linux-xanmod/myconfig" "${XDG_CONFIG_HOME}/linux-xanmod/myconfig" ; do
    if [ -f "${_myconfig}" ] && [ "$(wc -l <"${_myconfig}")" -gt "0" ]; then
      if grep -q 'scripts/config' "${_myconfig}"; then
        # myconfig is a partial file. Executing as a script
        msg2 "Applying myconfig..."
        bash -x "${_myconfig}"
      else
        # myconfig is a full config file. Replacing default .config
        msg2 "Using user CUSTOM config..."
        cp -f "${_myconfig}" .config
      fi
      echo
      break
    fi
  done

  make olddefconfig

  ### Optionally load needed modules for the make localmodconfig
  # See https://aur.archlinux.org/packages/modprobed-db
  if [ "$_localmodcfg" = "y" ]; then
    if [ -f $HOME/.config/modprobed.db ]; then
      msg2 "Running Steven Rostedt's make localmodconfig now"
      make LSMOD=$HOME/.config/modprobed.db localmodconfig
    else
      msg2 "No modprobed.db data found"
      exit 1
    fi
  fi

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

  if [ "$_makenconfig" = "y" ]; then
    make nconfig
  fi

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

build() {
  cd linux-${_major}
  make all
}

_package() {
  pkgdesc="The Linux kernel and modules with Xanmod patches"
  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
            KSMBD-MODULE
            NTFS3-MODULE)

  cd linux-${_major}
  local kernver="$(<version)"
  local modulesdir="$pkgdir/usr/lib/modules/$kernver"

  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"

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

  msg2 "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"
  depends=(pahole)

  cd linux-${_major}
  local builddir="$pkgdir/usr/lib/modules/$(<version)/build"

  msg2 "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 "$builddir/arch/x86" -m644 arch/x86/Makefile
  cp -t "$builddir" -a scripts

  # required when STACK_VALIDATION is enabled
  install -Dt "$builddir/tools/objtool" tools/objtool/objtool

  # required when DEBUG_INFO_BTF_MODULES is enabled
  if [ -f "$builddir/tools/bpf/resolve_btfids" ]; then install -Dt "$builddir/tools/bpf/resolve_btfids" tools/bpf/resolve_btfids/resolve_btfids ; fi

  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

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

  # https://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

  # https://bugs.archlinux.org/task/71392
  install -Dt "$builddir/drivers/iio/common/hid-sensors" -m644 drivers/iio/common/hid-sensors/*.h

  echo "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 "Stripping vmlinux..."
  strip -v $STRIP_STATIC "$builddir/vmlinux"
  
  msg2 "Adding symlink..."
  mkdir -p "$pkgdir/usr/src"
  ln -sr "$builddir" "$pkgdir/usr/src/$pkgbase"
}

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:
