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

_flavor=lts
pkgname=linux-$_flavor
pkgver=6.12.38
_kernver=${pkgver%.*}
pkgrel=0
pkgdesc="Linux lts kernel"
url="https://www.kernel.org"
depends="initramfs-generator"
_depends_dev="perl gmp-dev mpc1-dev mpfr-dev elfutils-dev bash flex bison zstd"
makedepends="$_depends_dev sed installkernel bc linux-headers linux-firmware-any openssl-dev>3 mawk
	diffutils findutils zstd pahole python3 gcc>=13.1.1_git20230624"
options="!strip !check"
_config=${config:-config-lts.${CARCH}}
source="https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/linux-$_kernver.tar.xz
	0001-powerpc-boot-wrapper-Add-z-notext-flag-for-ppc64le.patch
	0002-x86-Compress-vmlinux-with-zstd-19-instead-of-22.patch
	0003-kexec-add-kexec_load_disabled-boot-option.patch
	0004-objtool-respect-AWK-setting.patch
	0005-powerpc-config-defang-gcc-check-for-stack-protector-.patch
	0006-kallsyms-fix-build-without-execinfo.patch

	lts.aarch64.config
	lts.armv7.config
	lts.loongarch64.config
	lts.ppc64le.config
	lts.riscv64.config
	lts.s390x.config
	lts.x86.config
	lts.x86_64.config

	virt.aarch64.config
	virt.armv7.config
	virt.ppc64le.config
	virt.x86.config
	virt.x86_64.config
	"
subpackages="$pkgname-dev:_dev:$CBUILD_ARCH $pkgname-doc"
for _i in $source; do
	case $_i in
	*.$CARCH.config)
		_f=${_i%."$CARCH".config}
		_flavors="$_flavors $_f"
		if [ "linux-$_f" != "$pkgname" ]; then
			subpackages="$subpackages linux-$_f::$CBUILD_ARCH linux-$_f-dev:_dev:$CBUILD_ARCH"
		fi
		;;
	esac
done
builddir="$srcdir"/linux-$_kernver

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

# secfixes:
#   5.10.4-r0:
#     - CVE-2020-29568
#     - CVE-2020-29569
#   5.15.74-r0:
#     - CVE-2022-41674
#     - CVE-2022-42719
#     - CVE-2022-42720
#     - CVE-2022-42721
#     - CVE-2022-42722
#   6.1.27-r3:
#     - CVE-2023-32233
#   6.6.13-r1:
#     - CVE-46838

prepare() {
	default_prepare

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

_kernelarch() {
	local arch="$1"
	case "$arch" in
		aarch64*) arch="arm64" ;;
		arm*) arch="arm" ;;
		ppc*) arch="powerpc" ;;
		s390*) arch="s390" ;;
		riscv*) arch="riscv" ;;
		loongarch64) arch="loongarch" ;;
	esac
	echo "$arch"
}

_prepareconfig() {
	local _flavor="$1"
	local _arch="$2"
	local _config=$_flavor.$_arch.config
	local _builddir="$srcdir"/build-$_flavor.$_arch
	mkdir -p "$_builddir"
	echo "-$pkgrel-$_flavor" > "$_builddir"/localversion-alpine

	cp "$srcdir"/$_config "$_builddir"/.config
	msg "Configuring $_flavor kernel ($_arch)"
	make -C "$builddir" \
		O="$_builddir" \
		ARCH="$(_kernelarch $_arch)" \
		olddefconfig

	if grep "CONFIG_MODULE_SIG=y" "$_builddir"/.config >/dev/null; then
		if [ -f "$KERNEL_SIGNING_KEY" ]; then
			sed -i -e "s:^CONFIG_MODULE_SIG_KEY=.*:CONFIG_MODULE_SIG_KEY=\"$KERNEL_SIGNING_KEY\":" \
				"$_builddir"/.config
			msg "Using $KERNEL_SIGNING_KEY to sign $_flavor kernel ($_arch) modules"
		else
			warning "KERNEL_SIGNING_KEY was not set. A signing key will be generated, but 3rd"
			warning "party modules can not be signed"
		fi
	fi
}

listconfigs() {
	for i in $source; do
		case "$i" in
			*.config) echo $i;;
		esac
	done
}

prepareconfigs() {
	for _config in $(listconfigs); do
		local _flavor=${_config%%.*}
		local _arch=${_config%.config}
		_arch=${_arch#*.}
		local _builddir="$srcdir"/build-$_flavor.$_arch
		_prepareconfig "$_flavor" "$_arch"
	done
}

# this is supposed to be run before version is bumped so we can compare
# what new kernel config knobs are introduced
prepareupdate() {
	clean && fetch && unpack && prepare && deps
	prepareconfigs
	rm -r "$builddir"
}

updateconfigs() {
	if ! [ -d "$builddir" ]; then
		deps && fetch && unpack && prepare
	fi
	for _config in ${CONFIGS:-$(listconfigs)}; do
		msg "updating $_config"
		local _flavor=${_config%%.*}
		local _arch=${_config%.config}
		_arch=${_arch#*.}
		local _builddir="$srcdir"/build-$_flavor.$_arch
		mkdir -p "$_builddir"
		echo "-$pkgrel-$_flavor" > "$_builddir"/localversion-alpine
		local actions="listnewconfig oldconfig"
		if ! [ -f "$_builddir"/.config ]; then
			cp "$srcdir"/$_config "$_builddir"/.config
			actions="olddefconfig"
		fi
		env | grep ^CONFIG_ >> "$_builddir"/.config || true
		make -j1 -C "$builddir" \
			O="$_builddir" \
			ARCH="$(_kernelarch $_arch)" \
			$actions savedefconfig

		cp "$_builddir"/defconfig "$startdir"/$_config
	done
}

set_kbuild_timestamp() {
	# KBUILD_BUILD_TIMESTAMP needs to be parsable by busybox date
	export KBUILD_BUILD_TIMESTAMP="$(date '+%Y-%m-%d %H:%M:%S' -u${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"
}

build() {
	unset LDFLAGS
	# for some reason these sometimes leak into the kernel build,
	# -Werror=format-security breaks some stuff
	unset CFLAGS CPPFLAGS CXXFLAGS
	set_kbuild_timestamp
	for i in $_flavors; do
		_prepareconfig "$i" "$CARCH"
	done
	for i in $_flavors; do
		msg "Building $i kernel"
		cd "$srcdir"/build-$i.$CARCH

		# set org in cert for modules signing
		# https://www.kernel.org/doc/html/v6.1/admin-guide/module-signing.html#generating-signing-keys
		mkdir -p certs
		sed -e 's/#O = Unspecified company/O = alpinelinux.org/' \
			"$builddir"/certs/default_x509.genkey \
			> certs/x509.genkey

		make ARCH="$(_kernelarch $CARCH)" \
			CC="${CC:-gcc}" \
			AWK="${AWK:-mawk}" \
			KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-Alpine"
	done
}

_package() {
	local _buildflavor="$1" _outdir="$2"
	set_kbuild_timestamp

	cd "$srcdir"/build-$_buildflavor.$CARCH
	local _abi_release="$(make -s kernelrelease)"
	# 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|riscv*) _install="zinstall dtbs_install";;
		*) _install=install;;
	esac

	make modules_install $_install \
		ARCH="$(_kernelarch $CARCH)" \
		INSTALL_MOD_PATH="$_outdir" \
		INSTALL_MOD_STRIP=1 \
		INSTALL_PATH="$_outdir"/boot \
		INSTALL_DTBS_PATH="$_outdir/boot/dtbs-$_buildflavor"

	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 -m644 include/config/kernel.release \
		"$_outdir"/usr/share/kernel/$_buildflavor/kernel.release

	case "$CARCH" in
	loongarch64)
		mv  "$_outdir"/boot/vmlinuz-$_abi_release \
			"$_outdir"/boot/vmlinuz-$_buildflavor

		mv  "$_outdir"/boot/config-$_abi_release \
			"$_outdir"/boot/config-$_buildflavor

		mv  "$_outdir"/boot/System.map-$_abi_release \
			"$_outdir"/boot/System.map-$_buildflavor
		;;
	esac
}

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

	_package "$_flavor" "$pkgdir"

	# copy files for linux-lts-doc sub package
	mkdir -p "$pkgdir"/usr/share/doc
	cp -r "$builddir"/Documentation \
		"$pkgdir"/usr/share/doc/linux-doc-"$pkgver"/
	# remove files that aren't part of the documentation itself
	for nondoc in \
		.gitignore conf.py docutils.conf \
		dontdiff Kconfig Makefile
	do
		rm "$pkgdir"/usr/share/doc/linux-doc-"$pkgver"/"$nondoc"
	done
	# create /usr/share/doc/linux-doc symlink
	cd "$pkgdir"/usr/share/doc; ln -s linux-doc-"$pkgver" linux-doc
}

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

_dev() {
	local _flavor=$(echo $subpkgname | sed -E 's/(^linux-|-dev$)//g')
	local _builddir="$srcdir"/build-$_flavor.$CARCH
	local _abi_release="$(make -C "$_builddir" -s kernelrelease)"
	# 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"
	set_kbuild_timestamp

	# first we import config, run prepare to set up for building
	# external modules, and create the scripts
	mkdir -p "$dir"
	cp -a "$_builddir"/.config "$_builddir"/localversion-alpine \
		"$dir"/

	install -D -t "$dir"/certs "$_builddir"/certs/signing_key.x509 || :

	make -C "$builddir" \
		O="$dir" \
		ARCH="$(_kernelarch $CARCH)" \
		AWK="${AWK:-mawk}" \
		prepare modules_prepare scripts

	# remove the stuff that points to real sources. we want 3rd party
	# modules to believe this is the sources
	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 "$builddir"
	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 "arch/$_karch" -name include -type d -print | while IFS='' read -r folder; do
		find "$folder" -type f
	done | sort -u | cpio -pdm "$dir"

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

	# remove unneeded things
	msg "Removing documentation..."
	rm -r "$dir"/Documentation
	find "$dir" -type f -name '*.o' -printf 'Removing %P\n' -delete
	local _karch="$(_kernelarch $CARCH | sed 's/x86_64/x86/')"
	msg "Removing unneeded arch headers..."
	for i in "$dir"/arch/*; do
		if [ "${i##*/}" != "$_karch" ]; then
			echo "  ${i##*/}"
			rm -r "$i"
		fi
	done

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

sha512sums="
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a37b1823df7b4f72542f689b65882634740ba0401a42fdcf6601d9efd2e132e5a7650e70450ba76f6cd1f13ca31180f2ccee9d54fe4df89bc0000ade4380a548  linux-6.12.tar.xz
b296717ef0cd63978142b4d47b3bc49faa04daf77e115e702ba611cc254a6e782cdab7d5639e724cd5f029cfb6a3dc33c3036f346d681d1fdfe0df723c7e0321  0001-powerpc-boot-wrapper-Add-z-notext-flag-for-ppc64le.patch
055e10e7b3e00bb3621389315d5206a8feb5022a1f0dc51c3aa107facfe83d191da05a502a0c62488be7299677a63c1da84f87c42cbf3125788c56db67e810ee  0002-x86-Compress-vmlinux-with-zstd-19-instead-of-22.patch
7e066473fd0e234a279280eee0351bf9c3efab1e7ad0e1a85cb62193e63df06a7641015229445aaab6f68019c4852e6731b2cb3c4a54c0dbe405fac12b365873  0003-kexec-add-kexec_load_disabled-boot-option.patch
28c83be4c97152001381cd5e3a8acb8552a42d9dac9aaec8f096e3762b7944035aa5a4363fb4602f9bb427c4f72cfd2f996a0a725f7f9e07ab250317985aff9e  0004-objtool-respect-AWK-setting.patch
5ce79416f8f111c36393718656e3eeb4cb0adccd117dcf661876d1564010e5c58b6351cc4116d187d0a9a838bcca0fecc236d81ac71afb940b89ccb14f21e179  0005-powerpc-config-defang-gcc-check-for-stack-protector-.patch
a0660bd168f7e5804b995b8ec6ede423f2c8b9fa2d8904c165a4ddd4cadc88723f50c6fa9ffcb44f263f4e6c6fde600601210d77b8d3c2e25230e0b9438ca3c8  0006-kallsyms-fix-build-without-execinfo.patch
bdf8f7eaf635eff10ad808b3ea1cbb8500aa6d454083c1045e29103b57fa4e804c4478a5c91a868ff771adc3a496dfe5316cce8172543e02ddbe74ff629bb275  lts.aarch64.config
52f76a25dc4bbaaa03aa3dbfc8412051d0c2bef8c7c9e795e197f11eb461f1cb67660303898d8a22d1d239af567864324fbc55cb19cf1c8316e8d81ab0ec687c  lts.armv7.config
c8775e821134de67f493e72d6308dcfc1e462a49610af9a525d1464dc3efbae46e6727da9c5da1d0767c056d10810db9dc7fb9616c460dfc096eebdcce17dbfb  lts.loongarch64.config
ba030236d046c74daa8595067c29bc7879a8294baf19067061f7e3145c6ed1c0da8e52531819f10b4f316320449030a3ece23d4142885932d648f62e6c937648  lts.ppc64le.config
6c631d76bdceb4713cde8b5fefabed064f746cc254f76ff1d8bcd09d963789d0165bba9490f5fc77105bfa6f9fd43fdee16873c07275765417a738f40875f434  lts.riscv64.config
f11f4a39a7ba54d4ee8edb030c096e5121281427fad54c02056771318288588ef62cc5d7f07164e166d34e3a66a5a2b81d7f8904c5bb7f126bf06a62c37b07e3  lts.s390x.config
838656f0982121cb5473b7a7af961319950aa8640f7f38799427524fe02d4d0ed3fa2ee6e4448ce6e29a27dc89273989d90a176fb0aa0501b019bd80fb13cef2  lts.x86.config
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be6ad65122bf5d147a69d3bd91d94a1033f3cc6dfd23e11219851280c6d7166843b786aac178c1ddd0eeb98b5823755a55633b6592b4a815389c9776ed52df4b  virt.aarch64.config
dc9bf1b2687f436e9f75ee53c4e864cb9a5e4b62595e77bc00be341d2b224cc73b8e1718209d7cfb4376b3fb0c8f43d368e8f660d032aef45b8dbc0e6fc67956  virt.armv7.config
5d6d5f46d5785537498fbdf6079a8061a95609374dd545efccee2dc4ae4855106e8a7f5b2c5b3eaf353a9df3996b44f6ac0229b67fe4c011e0398a9e36dc9a40  virt.ppc64le.config
8d94d29526e376b20a0e28e876a9fd561adc0023e7f3d5f774db61ce413f4a779dd1d2894f714b9b25feb41f3b35c00767dde1eea3e12a44421b1394ef5a6570  virt.x86.config
cbfc841a1a321a3171cc3afe742668feff796e977d0028ed6939907ad2c92a73a2f984070fbaa15883ed3179affaac53b14dd0996b0bec906ff023eba3ca4c71  virt.x86_64.config
"
