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

_flavor=lts
pkgname=linux-${_flavor}
pkgver=5.4.3
case $pkgver in
	*.*.*)	_kernver=${pkgver%.*};;
	*.*) _kernver=$pkgver;;
esac
pkgrel=0
pkgdesc="Linux lts kernel"
url="http://kernel.org"
depends="mkinitfs"
_depends_dev="perl gmp-dev elfutils-dev bash flex bison"
makedepends="$_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
	config-lts.aarch64
	config-lts.armv7
	config-lts.x86
	config-lts.x86_64
	config-lts.ppc64le
	config-lts.s390x

	config-virt.aarch64
	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

HOSTCC="${CC:-gcc}"
HOSTCC="${HOSTCC#${CROSS_COMPILE}}"

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="$_carch" HOSTCC="$HOSTCC" \
			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 "$CARCH" in
	arm*)
		local _dtbdir="$_outdir"/boot/dtbs-lts
		mkdir -p "$_dtbdir"
		for i in arch/arm/boot/dts/*.dtb ; do
			install -m644 "$i" "$_dtbdir"
		done

		_install=zinstall
		;;
	*)
		_install=install
		;;
	esac

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

	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" HOSTCC="$HOSTCC" \
		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 \
		\( -name 'Makefile*' -o -name 'Kconfig*' -o -name 'Kbuild*' -o \
		   -name '*.sh' -o -name '*.pl' -o -name '*.lds' \) \
		-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
9c7299179f5bd4cb445c39d2c16c4a8aa555e7c802a5b009cb4ed25aa6af9ce308f4d615e623612c97e6011010ebcbae22620d079504a28611bfda25d6ab370a  config-lts.aarch64
f3e890fcfa8378c07996b28c4bbc04c15bb310c444c7299e542308195f1494689e129047e9b3a72a1f21d22ee07719573f57541238568ab9dfae0193e5f6bbf4  config-lts.armv7
9b5ebd87496bb121bcea14331e553dbb1d197f3091f958b3e961a07ba68ece7255bb12226bf86c5b82ec7a568c2e71d383af13a2264695cbe6c88d1664dd643c  config-lts.x86
bd815deb587c19be72c5221a4c3573f11e0c4950b8d97aa507c798b680ba1733ccb3f82e6934b85876f7cf94bc1cd3580091e6c2575f750c90eafc9357597519  config-lts.x86_64
a158573b244f80d0660690efced7e0a5a56c28352700f3ae171b23b0952272369837c5046512159ba3474ef46cc33da953f127fa50014b66db9cb6e63cc44d68  config-lts.ppc64le
f46c885f5325b698c86057f1c1286d76ec2b41ac9d20b36dcdbb88c55722b848c9ab52d0b9605f5f6e0588df34f4f223f0da420c3ee90127052c176e2ff2fc93  config-lts.s390x
ad13aef539f8abfdb861d4d2c75ee517270d500013f77e69a104c82c0a4e8d712fabe7ef41ae96a4d7996ab2a8159e4d35f36be20bc7579f3249b13bd8a12525  config-virt.aarch64
b4daedb6b96e77e40cf87d83a49acdf27aa8ae37f57e40dedf929336cbb28a173bea444a3b43b54bdcbe9822ef84e3fa92019993c419510911b2477c680dddab  config-virt.x86
c7f558fefa928a9ae87b3be9cfa8742f54533a9c7c7e721acd72131fcb8513d1763597ccd9fbc3a0af50d3ec880e0ecb733f4d18c9b550cda415d9c7fa657e2f  config-virt.x86_64
7146258dcd169552fdcc6ad02b709310e57d413be84c76061669712c840a6de3e8e104fdba763df284b465e0217a6e74435f1fb2e0faf16feb2d595193bd8a4a  patch-5.4.3.xz"