# Maintainer: Minoplhy <c@3qx.nl>

_flavor=zen
pkgname=linux-$_flavor
pkgver=6.12.1
_relver=zen1
#_kernver=${pkgver%.*}
_kernver=$pkgver
pkgrel=0
pkgdesc="Linux Zen kernel"
url="https://github.com/zen-kernel/zen-kernel"
depends="initramfs-generator"
_depends_dev="perl gmp-dev mpc1-dev mpfr-dev elfutils-dev bash flex bison zstd"
makedepends="$_depends_dev sed installkernel bc linux-headers linux-firmware-any openssl-dev>3 mawk
        diffutils findutils zstd pahole python3 gcc>=13.1.1_git20230624 zstd"
options="!strip !check"
_config=${config:-config-lts.${CARCH}}
source="https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/linux-$_kernver.tar.xz

        zen.x86_64.config
        zen.aarch64.config
        zen.armv7.config
        zen.loongarch64.config
        zen.ppc64le.config
        zen.riscv64.config
        zen.s390x.config
        zen.x86.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-$pkgver.patch.zst::https://github.com/zen-kernel/zen-kernel/releases/download/v$pkgver-$_relver/linux-v$pkgver-$_relver.patch.zst $source"
fi

arch="all !armhf !riscv64"
license="GPL-2.0-only"

prepare() {
        default_prepare

	for i in $source; do
		case ${i%::*} in
			*.patch.zst)
                                msg "${i%::*}"
                                # unzstd ignore symlink. so, realpath does the trick!
				unzstd -c "$(realpath $srcdir/$(filename_from_uri $i))" | patch ${patch_args:--p1} || failed="$failed $i"
				;;
                esac
        done

        # 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="
2b6e206c954199789010bbd87e1219495d3d4b4f26e6ca3b138f81ce9cea8817a0a87e949e661d96113854c3a539f4dd70f1db745188b90bda47d1a68a0d488d  patch-6.11.9.patch
aed30b6f1b216b1b9fa829787f18f124d0d7fe76e96c90e594ed70a64e07d23d10b536dfa727a7906c27add717881b110bbed76b7cb0a0dcbc98fe1c8b4d3392  v6.11.9-hardened1.tar.gz
ff49e4218bb73e8ab6a49b2c7045b1db90d1d777eccdc2a9aafdef64a9537ee18fe3f6233d3e8143a45d25b681981e43354f98e8ea8cb0a23539a4d36f14256a  hardened.x86_64.config
"