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

_flavor=lts
pkgname=linux-${_flavor}
pkgver=5.4.40
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
}

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d19365fe94431008768c96a2c88955652f70b6df6677457ee55ee95246a64fdd2c6fed9b3bef37c29075178294a7fc91f148ead636382530ebfa822be4ad8c2f  0002-powerpc-config-defang-gcc-check-for-stack-protector-.patch
7e2382b272ee08eed39677f63cac24f1b61b712406d9eb78426610a2099022ea19d5ed1f5f96ff77d4290f1d0c67ca18e69be27779c20c4dca7375dd8b8d17aa  config-lts.aarch64
d5173bb9bd613d4163eccc24d771f983011b4188d97f7ea00a73f03a4a01b879177b6aafebd2480545ecbf55a2e6477230bef28376cea01fbbd89a6334686613  config-lts.armv7
11735694f31a4a037aacb242253d5587a4e72aaa259abac7268a373b07f80c407b10adf7833ebb960e91edced19d1c41bcdd46ef60ab39a00eaac8fa9291a398  config-lts.x86
b91d5f4664ca4a3e1327266156660b2539ab3a5c27e5938b67963bbdfe290cc1a7344629574bb3fdcb2faa6e005b84c0d9a316618f36dcc665a24926dcb769a1  config-lts.x86_64
9cf2b3d247c923930497e249629e20a250098b9147bbd197864da0042c20b50272b2c6d5f781a997f90fbf3615b568f3716af672c680312b54a2a184d64e5025  config-lts.ppc64le
00aed49ab795ee3fae5cd6706e825966c5af133834fc86fea1cd237764611ee2466b47e8071c925b54a005c80d05fc5b20321c56ac292694e984c7cd62a77529  config-lts.s390x
6fd1535b43e7c495cb07ebabe7e346d027df2573e03c6cc567d5252f989c6ec5782623e9cb35481adfbd27694349d605346ec9f206b38ed342321325511835ac  config-lts.mips64
749bd90332d164e5e448f7fa427fed0556d4388dface08fd90d2f7233f2f9c4a342948d7069488fabe33ce2537b6c7b0a83f408e4025f0797e84adb2ef658148  config-lts.mips
4f56464839ea783da99e19a3d7703d1ce590f7b160b1246933badecbd98d732e9c62aec1f3e04b10efa607103220ab7a7f9440d1e50cfbb95680f7fdc032457d  config-virt.aarch64
24d4c1fc4da65ea863837dc064ce5b3bf3c0a22c36eeaf3d56492ee1dd9f6fb775cee19ec62e17cbfce3a4a14b2c334bb0190976fe6bbc3b4ce1057b3ae0ef11  config-virt.armv7
ebd393804a914743ba5800ba56c6772d7c47a8ce5a2c73a9e5ca45bed3bfffda4184e54bfb237c7519c51ef39b24f3abb59d4f85c3840dfb6cebdc1189b5ab64  config-virt.x86
ae8c3034845fa90336434fb598a0a1beac349aa55711c62fc5967334b42ebfc8f2a9e49f7d992ae65b1390b003cd1222cde07148d9ad72dbb533e53450480a64  config-virt.x86_64
20c19808a7e2af62ea93a4ae187db5e80078da8c4b268424c8d6f945a98eeb0ce7b1f09086813fbd9a9220ff5f062c1fcb8292abedfdc7f9d23a2d804898cd16  patch-5.4.40.xz"