# Copyright 2020-2023 BaldEagleOS Authors
# Distributed under the terms of the GNU General Public License v2

# Documentation for adding new kernels -- do not remove!
#
# Find latest kernel release here:
#   https://github.com/openSUSE/kernel/releases

EAPI=8

inherit check-reqs mount-boot toolchain-funcs

DESCRIPTION="OpenSUSE Sources (and optional binary kernel)"
HOMEPAGE="https://github.com/openSUSE/kernel"
LICENSE="GPL-2"
KEYWORDS="x86 amd64"

SLOT=$(ver_cut 1-2)

RESTRICT="binchecks strip mirror"

IUSE="binary btrfs dtrace custom-cflags ec2 luks lvm sign-modules zfs debug firmware mdadm mcelog plymouth systemd wireguard"

BDEPEND="
	virtual/libelf
	debug? ( dev-util/dwarves )
	sys-devel/bc
"

DEPEND="
        net-misc/dhcp[client]
        binary? (
                sys-kernel/dracut
                dev-util/pahole
                )
        btrfs? ( sys-fs/btrfs-progs )
        dtrace? (
                dev-util/dtrace-utils
                dev-libs/libdtrace-ctf
        )
        firmware? (
                sys-kernel/linux-firmware
        )
        luks? ( sys-fs/cryptsetup )
        lvm? ( sys-fs/lvm2 )
        mdadm? ( sys-fs/mdadm )
        mcelog? ( app-admin/mcelog )
        plymouth? (
                x11-libs/libdrm[libkms]
                sys-boot/plymouth[udev]
        )
        sign-modules? (
                || ( dev-libs/openssl
                     dev-libs/libressl
        )
                sys-apps/kmod
        )
        systemd? ( sys-apps/systemd )
        !systemd? ( sys-fs/eudev )
        wireguard? ( virtual/wireguard )
        zfs? ( sys-fs/zfs )
"

SRC_URI="https://github.com/openSUSE/kernel/archive/v${PV}.tar.gz -> linux_${PV}.tar.gz"
S="$WORKDIR/kernel-${PV}"
# install sources to /usr/src/$LINUX_SRCDIR
LINUX_SRCDIR=linux-${PF}

get_patch_list() {
	[[ -z "${1}" ]] && die "No patch series file specified"
	local patch_series="${1}"
	while read line ; do
		if [[ "${line:0:1}" != "#" ]] ; then
			echo "${line}"
		fi
	done < "${patch_series}"
}

tweak_config() {
	einfo "Setting $2=$3 in kernel config."
	sed -i -e "/^$2=/d" $1
	echo "$2=$3" >> $1
}

setno_config() {
	einfo "Setting $2*=y to n in kernel config."
	sed -i -e "s/^$2\(.*\)=.*/$2\1=n/g" $1
}

setyes_config() {
	einfo "Setting $2*=* to y in kernel config."
	sed -i -e "s/^$2\(.*\)=.*/$2\1=y/g" $1
}

zap_config() {
	einfo "Removing *$2* from kernel config."
	sed -i -e "/$2/d" $1
}

pkg_pretend() {
	# Ensure we have enough disk space to compile
	if use binary ; then
		CHECKREQS_DISK_BUILD="5G"
		check-reqs_pkg_setup
	fi
}

get_certs_dir() {
	# find a certificate dir in /etc/kernel/certs/ that contains signing cert for modules.
	for subdir in $PF $P linux; do
		certdir=/etc/kernel/certs/$subdir
		if [ -d $certdir ]; then
			if [ ! -e $certdir/signing_key.pem ]; then
				eerror "$certdir exists but missing signing key; exiting."
				exit 1
			fi
			echo $certdir
			return
		fi
	done
}

pkg_setup() {
	export REAL_ARCH="$ARCH"
	unset ARCH; unset LDFLAGS #will interfere with Makefile if set
}

src_prepare() {
	default

	eapply -p1 "${FILESDIR}/shiftfs.patch"

	cd "${S}"
	#for debpatch in $( get_patch_list "${WORKDIR}/debian/patches/series" ); do
	#	epatch -p1 "${WORKDIR}/debian/patches/${debpatch}"
	#done
	# end of debian-specific stuff...

	# do not include debian devs certificates
	#rm -rf "${WORKDIR}"/debian/certs

	sed -i -e "s:^\(EXTRAVERSION =\).*:\1 ${MODULE_EXT}:" Makefile || die
	sed	-i -e 's:#export\tINSTALL_PATH:export\tINSTALL_PATH:' Makefile || die
	rm -f .config >/dev/null
	#cp -a "${WORKDIR}"/debian "${T}"
	#make -s mrproper || die "make mrproper failed"
	#make -s include/linux/version.h || die "make include/linux/version.h failed"
	#cd "${S}"
	#cp -aR "${WORKDIR}"/debian "${S}"/debian

	## XFS LIBCRC kernel config fixes, FL-823
	#epatch "${FILESDIR}"/${DEB_PV_BASE}/${PN}-${DEB_PV_BASE}-xfs-libcrc32c-fix.patch

	## FL-4424: enable legacy support for MCELOG.
	#epatch "${FILESDIR}"/${DEB_PV_BASE}/${PN}-${DEB_PV_BASE}-mcelog.patch

	## do not configure debian devs certs.
	#epatch "${FILESDIR}"/${DEB_PV_BASE}/${PN}-${DEB_PV_BASE}-nocerts.patch

	## FL-3381. enable IKCONFIG
	#epatch "${FILESDIR}"/${DEB_PV_BASE}/${PN}-${DEB_PV_BASE}-ikconfig.patch

	## increase bluetooth polling patch
	#epatch "${FILESDIR}"/${DEB_PV_BASE}/${PN}-${DEB_PV_BASE}-fix-bluetooth-polling.patch
	#epatch "${FILESDIR}"/${DEB_PV_BASE}/export_kernel_fpu_functions_5_3.patch


	local arch featureset subarch
	featureset="standard"
	if [[ ${REAL_ARCH} == x86 ]]; then
		arch="i386"
		subarch="686-pae"
	elif [[ ${REAL_ARCH} == amd64 ]]; then
		arch="x86_64"
		subarch="amd64"
	else
	die "Architecture not handled in ebuild"
	fi
	#cp "${FILESDIR}"/config-extract . || die
	#chmod +x config-extract || die
	#./config-extract ${arch} ${featureset} ${subarch} || die
	tar -xvaf "${FILESDIR}/config.tar.bz2" config/${arch}/default
	mv config/${arch}/default .config
	setno_config .config CONFIG_DEBUG
	if use ec2; then
		setyes_config .config CONFIG_BLK_DEV_NVME
		setyes_config .config CONFIG_XEN_BLKDEV_FRONTEND
		setyes_config .config CONFIG_XEN_BLKDEV_BACKEND
		setyes_config .config CONFIG_IXGBEVF
	fi
	if use sign-modules; then
		certs_dir=$(get_certs_dir)
		echo
		if [ -z "$certs_dir" ]; then
			eerror "No certs dir found in /etc/kernel/certs; aborting."
			die
		else
			einfo "Using certificate directory of $certs_dir for kernel module signing."
		fi
		echo
		# turn on options for signing modules.
		# first, remove existing configs and comments:
		zap_config .config CONFIG_MODULE_SIG
		# now add our settings:
		tweak_config .config CONFIG_MODULE_SIG y
		tweak_config .config CONFIG_MODULE_SIG_FORCE n
		tweak_config .config CONFIG_MODULE_SIG_ALL n
		tweak_config .config CONFIG_MODULE_SIG_HASH \"sha512\"
		tweak_config .config CONFIG_MODULE_SIG_KEY  \"${certs_dir}/signing_key.pem\"
		tweak_config .config CONFIG_SYSTEM_TRUSTED_KEYRING y
		tweak_config .config CONFIG_SYSTEM_EXTRA_CERTIFICATE y
		tweak_config .config CONFIG_SYSTEM_EXTRA_CERTIFICATE_SIZE 4096
		echo "CONFIG_MODULE_SIG_SHA512=y" >> .config
		ewarn "This kernel will ALLOW non-signed modules to be loaded with a WARNING."
		ewarn "To enable strict enforcement, YOU MUST add module.sig_enforce=1 as a kernel boot"
		ewarn "parameter (to params in /etc/boot.conf, and re-run boot-update.)"
		echo
	fi
	if use custom-cflags; then
		MARCH="$(python -c "import portage; print(portage.settings[\"CFLAGS\"])" | sed 's/ /\n/g' | grep "march")"
		if [ -n "$MARCH" ]; then
			sed -i -e 's/-mtune=generic/$MARCH/g' arch/x86/Makefile || die "Canna optimize this kernel anymore, captain!"
		fi
	fi
	# get config into good state:
	yes "" | make oldconfig >/dev/null 2>&1 || die
	cp .config "${T}"/config || die
	#make -s mrproper || die "make mrproper failed"
}

src_configure() {
        if use binary; then

        debug-print-function ${FUNCNAME} "${@}"

        tc-export_build_env
        MAKEARGS=(
            V=1

            HOSTCC="$(tc-getBUILD_CC)"
            HOSTCXX="$(tc-getBUILD_CXX)"
            HOSTCFLAGS="${BUILD_CFLAGS}"
            HOSTLDFLAGS="${BUILD_LDFLAGS}"

            CROSS_COMPILE=${CHOST}-
            AS="$(tc-getAS)"
            CC="$(tc-getCC)"
            LD="$(tc-getLD)"
            AR="$(tc-getAR)"
            NM="$(tc-getNM)"
            STRIP=":"
            OBJCOPY="$(tc-getOBJCOPY)"
            OBJDUMP="$(tc-getOBJDUMP)"

            # we need to pass it to override colliding Gentoo envvar
            ARCH=$(tc-arch-kernel)
        )

        mkdir -p "${WORKDIR}"/modprep || die
        cp "${T}"/.config "${WORKDIR}"/modprep/ || die
        emake O="${WORKDIR}"/modprep "${MAKEARGS[@]}" olddefconfig || die "kernel configure failed"
        emake O="${WORKDIR}"/modprep "${MAKEARGS[@]}" modules_prepare || die "modules_prepare failed"
        cp -pR "${WORKDIR}"/modprep "${WORKDIR}"/build || die
    fi
}

src_compile() {
        if use binary; then
        debug-print-function ${FUNCNAME} "${@}"

        emake O="${WORKDIR}"/build "${MAKEARGS[@]}" all || "kernel build failed"
    fi
}

src_install() {
	# copy sources into place:
	dodir /usr/src
	cp -a "${S}" "${D}"/usr/src/${LINUX_SRCDIR} || die
	cd "${D}"/usr/src/${LINUX_SRCDIR}
	# prepare for real-world use and 3rd-party module building:
	make mrproper || die
	cp "${T}"/config .config || die


	# if we didn't use genkernel, we're done. The kernel source tree is left in
	# an unconfigured state - you can't compile 3rd-party modules against it yet.
	use binary || return
	make prepare || die
	make scripts || die
	# OK, now the source tree is configured to allow 3rd-party modules to be
	# built against it, since we want that to work since we have a binary kernel
	# built.
	cp -a "${WORKDIR}"/out/* "${D}"/ || die "couldn't copy output files into place"
	# module symlink fixup:
	rm -f "${D}"/lib/modules/*/source || die
	rm -f "${D}"/lib/modules/*/build || die
	cd "${D}"/lib/modules
	local moddir="$(ls -d [234]*)"
	ln -s /usr/src/${LINUX_SRCDIR} "${D}"/lib/modules/${moddir}/source || die
	ln -s /usr/src/${LINUX_SRCDIR} "${D}"/lib/modules/${moddir}/build || die
	# Fixes FL-14
	cp "${WORKDIR}/build/System.map" "${D}/usr/src/${LINUX_SRCDIR}/" || die
	cp "${WORKDIR}/build/Module.symvers" "${D}/usr/src/${LINUX_SRCDIR}/" || die
	if use sign-modules; then
		for x in $(find "${D}"/lib/modules -iname *.ko); do
			# $certs_dir defined previously in this function.
			${WORKDIR}/build/scripts/sign-file sha512 $certs_dir/signing_key.pem $certs_dir/signing_key.x509 $x || die
		done
		# install the sign-file executable for future use.
		exeinto /usr/src/${LINUX_SRCDIR}/scripts
		doexe ${WORKDIR}/build/scripts/sign-file
	fi

	# The new naming scheme leaves an extra -${PN} at the name of various things in /boot. This should fix that.
	cd ${D}/boot
	for x in $(ls *); do
		xnew=${x%-${PN}}
		mv $x ${xnew} || die
	done


}

pkg_postinst() {
	if use binary && [[ -h "${ROOT}"usr/src/linux ]]; then
		rm "${ROOT}"usr/src/linux
	fi
	if use binary && [[ ! -e "${ROOT}"usr/src/linux ]]; then
		ewarn "With binary use flag enabled /usr/src/linux"
		ewarn "symlink automatically set to debian kernel"
		ln -sf ${LINUX_SRCDIR} "${ROOT}"usr/src/linux
	fi

	if [ -e ${ROOT}lib/modules ]; then
		depmod -a $DEP_PV
	fi
	if [ -e /etc/boot.conf ]; then
		ego boot update
	fi
}