# Maintainer: Natanael Copa <ncopa@alpinelinux.org>

_flavor=lts
pkgname=linux-${_flavor}
pkgver=5.4.35
case $pkgver in
	*.*.*)	_kernver=${pkgver%.*};;
	*.*) _kernver=$pkgver;;
esac
pkgrel=0
pkgdesc="Linux lts kernel"
url="https://www.kernel.org"
depends="mkinitfs"
_depends_dev="perl gmp-dev elfutils-dev bash flex bison"
makedepends="$_depends_dev sed installkernel bc linux-headers linux-firmware-any openssl-dev
	diffutils"
options="!strip"
_config=${config:-config-lts.${CARCH}}
install=
source="https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/linux-$_kernver.tar.xz
	0002-powerpc-config-defang-gcc-check-for-stack-protector-.patch

	config-lts.aarch64
	config-lts.armv7
	config-lts.x86
	config-lts.x86_64
	config-lts.ppc64le
	config-lts.s390x
	config-lts.mips64
	config-lts.mips

	config-virt.aarch64
	config-virt.armv7
	config-virt.x86
	config-virt.x86_64
	"
subpackages="$pkgname-dev:_dev:$CBUILD_ARCH"
_flavors=
for _i in $source; do
	case $_i in
	config-*.$CARCH)
		_f=${_i%.$CARCH}
		_f=${_f#config-}
		_flavors="$_flavors ${_f}"
		if [ "linux-$_f" != "$pkgname" ]; then
			subpackages="$subpackages linux-${_f}::$CBUILD_ARCH linux-${_f}-dev:_dev:$CBUILD_ARCH"
		fi
		;;
	esac
done

if [ "${pkgver%.0}" = "$pkgver" ]; then
	source="$source
	https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/patch-$pkgver.xz"
fi
arch="all !armhf"
license="GPL-2.0"

_carch=${CARCH}
case "$_carch" in
aarch64*) _carch="arm64" ;;
arm*) _carch="arm" ;;
mips*) _carch="mips" ;;
ppc*) _carch="powerpc" ;;
s390*) _carch="s390" ;;
esac

prepare() {
	local _patch_failed=
	cd "$srcdir"/linux-$_kernver
	if [ "$_kernver" != "$pkgver" ]; then
		msg "Applying patch-$pkgver.xz"
		unxz -c < "$srcdir"/patch-$pkgver.xz | patch -p1 -N
	fi

	# first apply patches in specified order
	for i in $source; do
		case $i in
		*.patch)
			msg "Applying $i..."
			if ! patch -s -p1 -N -i "$srcdir"/$i; then
				echo $i >>failed
				_patch_failed=1
			fi
			;;
		esac
	done

	if ! [ -z "$_patch_failed" ]; then
		error "The following patches failed:"
		cat failed
		return 1
	fi

	# remove localversion from patch if any
	rm -f localversion*
	oldconfig
}

oldconfig() {
	for i in $_flavors; do
		local _config=config-$i.${CARCH}
		local _builddir="$srcdir"/build-$i.$CARCH
		mkdir -p "$_builddir"
		echo "-$pkgrel-$i" > "$_builddir"/localversion-alpine \
			|| return 1

		cp "$srcdir"/$_config "$_builddir"/.config
		make -C "$srcdir"/linux-$_kernver \
			O="$_builddir" \
			ARCH="$_carch" \
			listnewconfig oldconfig
	done
}

build() {
	unset LDFLAGS
	export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"
	for i in $_flavors; do
		cd "$srcdir"/build-$i.$CARCH
		make ARCH="$_carch" CC="${CC:-gcc}" \
			KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-Alpine"
	done
}

_package() {
	local _buildflavor="$1" _outdir="$2"
	local _abi_release=${pkgver}-${pkgrel}-${_buildflavor}
	export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

	cd "$srcdir"/build-$_buildflavor.$CARCH
	# modules_install seems to regenerate a defect Modules.symvers on s390x. Work
	# around it by backing it up and restore it after modules_install
	cp Module.symvers Module.symvers.backup

	mkdir -p "$_outdir"/boot "$_outdir"/lib/modules

	local _install
	case "$CARCH" in
		arm*|aarch64) _install="zinstall dtbs_install";;
		*) _install=install;;
	esac

	make -j1 modules_install $_install \
		ARCH="$_carch" \
		INSTALL_MOD_PATH="$_outdir" \
		INSTALL_PATH="$_outdir"/boot \
		INSTALL_DTBS_PATH="$_outdir/boot/dtbs-$_flavor"

	cp Module.symvers.backup Module.symvers

	rm -f "$_outdir"/lib/modules/${_abi_release}/build \
		"$_outdir"/lib/modules/${_abi_release}/source
	rm -rf "$_outdir"/lib/firmware

	install -D include/config/kernel.release \
		"$_outdir"/usr/share/kernel/$_buildflavor/kernel.release
}

# main flavor installs in $pkgdir
package() {
	depends="$depends linux-firmware-any"

	_package lts "$pkgdir"
}

# subflavors install in $subpkgdir
virt() {
	_package virt "$subpkgdir"
}

_dev() {
	local _flavor=$(echo $subpkgname | sed -E 's/(^linux-|-dev$)//g')
	local _abi_release=${pkgver}-${pkgrel}-$_flavor
	# copy the only the parts that we really need for build 3rd party
	# kernel modules and install those as /usr/src/linux-headers,
	# simlar to what ubuntu does
	#
	# this way you dont need to install the 300-400 kernel sources to
	# build a tiny kernel module
	#
	pkgdesc="Headers and script for third party modules for $_flavor kernel"
	depends="$_depends_dev"
	local dir="$subpkgdir"/usr/src/linux-headers-${_abi_release}
	export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

	# first we import config, run prepare to set up for building
	# external modules, and create the scripts
	mkdir -p "$dir"
	cp "$srcdir"/config-$_flavor.${CARCH} "$dir"/.config
	echo "-$pkgrel-$_flavor" > "$dir"/localversion-alpine

	make -j1 -C "$srcdir"/linux-$_kernver O="$dir" ARCH="$_carch" \
		syncconfig prepare modules_prepare scripts

	# remove the stuff that points to real sources. we want 3rd party
	# modules to believe this is the soruces
	rm "$dir"/Makefile "$dir"/source

	# copy the needed stuff from real sources
	#
	# this is taken from ubuntu kernel build script
	# http://kernel.ubuntu.com/git/ubuntu/ubuntu-zesty.git/tree/debian/rules.d/3-binary-indep.mk
	cd "$srcdir"/linux-$_kernver
	find .  -path './include/*' -prune \
		-o -path './scripts/*' -prune -o -type f \
		\( -name 'Makefile*' -o -name 'Kconfig*' -o -name 'Kbuild*' -o \
		   -name '*.sh' -o -name '*.pl' -o -name '*.lds' -o -name 'Platform' \) \
		-print | cpio -pdm "$dir"

	cp -a scripts include "$dir"

	find $(find arch -name include -type d -print) -type f \
		| cpio -pdm "$dir"

	install -Dm644 "$srcdir"/build-$_flavor.$CARCH/Module.symvers \
		"$dir"/Module.symvers

	mkdir -p "$subpkgdir"/lib/modules/${_abi_release}
	ln -sf /usr/src/linux-headers-${_abi_release} \
		"$subpkgdir"/lib/modules/${_abi_release}/build
}

sha512sums="9f60f77e8ab972b9438ac648bed17551c8491d6585a5e85f694b2eaa4c623fbc61eb18419b2656b6795eac5deec0edaa04547fc6723fbda52256bd7f3486898f  linux-5.4.tar.xz
d19365fe94431008768c96a2c88955652f70b6df6677457ee55ee95246a64fdd2c6fed9b3bef37c29075178294a7fc91f148ead636382530ebfa822be4ad8c2f  0002-powerpc-config-defang-gcc-check-for-stack-protector-.patch
1d06ba4480a547c33f16054d8e556e74b1fd0d9a03023f4e66560a9f282056ec5782ab0eb309ff7b551b52c24fbd453603678631f90713164b5cb11bdad005ff  config-lts.aarch64
76d29004ebe0d73566bd9a3d8ed177815f9340678fa1f4fb58999d701c8659aa779a51d2d5ed355dfae993728ecfddc7f89488946b5cd90f7e54d5f2af1feb4a  config-lts.armv7
fba2e913421fc4598b3fde368a9a403ae6aba7380aaf370681a0ce7881d2b2ae1468d9eb69c1a6883725d7a20983c59cac0ebd8338fd5c257c7e40edc521b828  config-lts.x86
0c53a969414a079ac88f23a2a80da4666e7f0bb4b2417015fab2f783a10ab3037e4e7b2335c2b0b788b98345c63f80b313c2b1583edb7ecdf5c246bba625f0ff  config-lts.x86_64
b843b6965bd82354170615ad560774d1f3c4c397eb5f973c0739873ee7ee75701ab6da0535751f1f1a147cbbed227e604c72532072f992ed7b7779b44c4a3b69  config-lts.ppc64le
e6624e4ac64bd7bf44891db562620953404275e9fd09ff3b0553890e951f04a15f49af92b10b4694bc547b1d4bcad4958300589137a50596db98ee5adc3262bd  config-lts.s390x
3809ae11d08ee672888e9545ff54dfb6c61a3bb4b8b0939a929fd6e728775ac270cd34a75647ade44467d8ebe626c4b32d14e4cbd8e2a49726c3141ddae53f22  config-lts.mips64
90b3d7fcf83377bae5a839d286fd6c9ea20eefa5b4062cc99307837c80d0dd6eb6352057ccbcf9f9b95f4875eb77e3f883dc65eb1bdd34162e8a10df7f0c632e  config-lts.mips
4603b18dcc2e56332ae343f85cb5be4b320d8ce70ce343a5471363a252b1ca7a5eb8cf8377fb9df98cd5d62806278431ddf955ab87ae79fba037dac9b1ce9ef1  config-virt.aarch64
59a8c29db5761b5c4737c58ae3465b1398548250e885c70d99d3531ce9b6210114e511068a29503134e404ab33c4c2a6cb365809164d8dd0a9f207a2ae2a00b7  config-virt.armv7
19c2176a81191d5bfc1adaf037e5f50a8cb20e5c8aa20a87e2364ffae75f62e6af28cad865e22fbb7b20aa698ce38f06b371fd7c1c6985b24a474b2531a27c0d  config-virt.x86
76d4fac5578035b34abaf4c0f74f469d252f992d305f83a6a87b8155574c2346efbefb7943d5ebe38641f2fbd4aee67808883fe6f03df1b758426e7b8e1303a8  config-virt.x86_64
d697462715c01f40a4c85317f98ffb22d0eac6365041e286ed0d01afedab7285f7183c87cd6eb34971a66f6113d620ae7478bb946268d8f5889b062b7f0d4642  patch-5.4.35.xz"