FROM scratch AS base
ENV VERSION=6.6
ENV SRC_HASH=d926a06c63dd8ac7df3f86ee1ffc2ce2a3b81a2d168484e76b5b389aba8e56d0
ENV SRC_FILE=linux-${VERSION}.tar.xz
ENV SRC_SITE=http://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/${SRC_FILE}

FROM base AS fetch
ADD --checksum=sha256:${SRC_HASH} ${SRC_SITE} .

FROM fetch AS build
COPY --from=stagex/musl . /
COPY --from=stagex/make . /
COPY --from=stagex/binutils . /
COPY --from=stagex/linux-headers . /
COPY --from=stagex/elfutils . /
COPY --from=stagex/openssl . /
COPY --from=stagex/perl . /
COPY --from=stagex/m4 . /
COPY --from=stagex/gcc . /
COPY --from=stagex/bison . /
COPY --from=stagex/libzstd . /
COPY --from=stagex/zlib . /
COPY --from=stagex/flex . /
COPY --from=stagex/pkgconf . /
COPY --from=stagex/coreutils . /
COPY --from=stagex/findutils . /
COPY --from=stagex/diffutils . /
COPY --from=stagex/tar . /
COPY --from=stagex/gzip . /
COPY --from=stagex/xz . /
COPY --from=stagex/sed . /
COPY --from=stagex/grep . /
COPY --from=stagex/gawk . /
COPY --from=stagex/bc . /
COPY --from=stagex/bash . /
COPY --from=stagex/bash /bin/bash /bin/sh
RUN tar -xf ${SRC_FILE}
WORKDIR linux-${VERSION}
ENV KBUILD_BUILD_HOST=stagex
ENV KBUILD_BUILD_USER=user
ENV KBUILD_BUILD_TIMESTAMP=1
RUN <<-EOF
	set -eux
	unsetConfs='
		CONFIG_BLK_DEV_INITRD
	'
	make defconfig
	for conf in $unsetConfs; do
		sed -i \
			-e "s!^$conf=.*\$!# $conf is not set!" \
			.config
	done
	make oldconfig
	for conf in $unsetConfs; do
		! grep -q "^$conf=" .config
	done
	make oldconfig
	make -j "$(nproc)" bzImage
	make -j "$(nproc)" modules INSTALL_MOD_PATH=/rootfs
EOF

FROM build AS install
RUN <<-EOF
	set -eux
    mkdir -p /rootfs/usr/lib/modules
    make INSTALL_MOD_PATH=/rootfs/usr modules_install
	cp .config /rootfs/linux.config
	cp arch/x86_64/boot/bzImage /rootfs
EOF

FROM stagex/filesystem AS package
COPY --from=install /rootfs/. /