#!/bin/sh
#
# builddeb 1.3
# Copyright 2003 Wichert Akkerman <wichert@wiggy.net>
#
# Simple script to generate a deb package for a Linux kernel. All the
# complexity of what to do with a kernel after it is installed or removed
# is left to other scripts and packages: they can install scripts in the
# /etc/kernel/{pre,post}{inst,rm}.d/ directories (or an alternative location
# specified in KDEB_HOOKDIR) that will be called on package install and
# removal.

set -e

is_enabled() {
	grep -q "^$1=y" include/config/auto.conf
}

if_enabled_echo() {
	if is_enabled "$1"; then
		echo -n "$2"
	elif [ $# -ge 3 ]; then
		echo -n "$3"
	fi
}

create_package() {
	local pname="$1" pdir="$2"
	local dpkg_deb_opts

	mkdir -m 755 -p "$pdir/DEBIAN"
	mkdir -p "$pdir/usr/share/doc/$pname"
	cp debian/copyright "$pdir/usr/share/doc/$pname/"
	cp debian/changelog "$pdir/usr/share/doc/$pname/changelog.Debian"
	gzip -n -9 "$pdir/usr/share/doc/$pname/changelog.Debian"
	sh -c "cd '$pdir'; find . -type f ! -path './DEBIAN/*' -printf '%P\0' \
		| xargs -r0 md5sum > DEBIAN/md5sums"

	# Fix ownership and permissions
	if [ "$DEB_RULES_REQUIRES_ROOT" = "no" ]; then
		dpkg_deb_opts="--root-owner-group"
	else
		chown -R root:root "$pdir"
	fi
	chmod -R go-w "$pdir"
	# in case we are in a restrictive umask environment like 0077
	chmod -R a+rX "$pdir"
	# in case we build in a setuid/setgid directory
	chmod -R ug-s "$pdir"

	# Create the package
	dpkg-gencontrol -p$pname -P"$pdir"
	dpkg-deb $dpkg_deb_opts ${KDEB_COMPRESS:+-Z$KDEB_COMPRESS} --build "$pdir" ..
}

deploy_kernel_headers () {
	pdir=$1

	rm -rf $pdir

	(
		cd $srctree
		find . arch/$SRCARCH -maxdepth 1 -name Makefile\*
		find include scripts -type f -o -type l
		find arch/$SRCARCH -name Kbuild.platforms -o -name Platform
		find $(find arch/$SRCARCH -name include -o -name scripts -type d) -type f
	) > debian/hdrsrcfiles

	{
		if is_enabled CONFIG_OBJTOOL; then
			echo tools/objtool/objtool
		fi

		find arch/$SRCARCH/include Module.symvers include scripts -type f

		if is_enabled CONFIG_GCC_PLUGINS; then
			find scripts/gcc-plugins -name \*.so
		fi
	} > debian/hdrobjfiles

	destdir=$pdir/usr/src/linux-headers-$version
	mkdir -p $destdir
	tar -c -f - -C $srctree -T debian/hdrsrcfiles | tar -xf - -C $destdir
	tar -c -f - -T debian/hdrobjfiles | tar -xf - -C $destdir
	rm -f debian/hdrsrcfiles debian/hdrobjfiles

	# copy .config manually to be where it's expected to be
	cp $KCONFIG_CONFIG $destdir/.config

	mkdir -p $pdir/lib/modules/$version/
	ln -s /usr/src/linux-headers-$version $pdir/lib/modules/$version/build
}

deploy_libc_headers () {
	pdir=$1

	rm -rf $pdir

	$MAKE -f $srctree/Makefile headers
	$MAKE -f $srctree/Makefile headers_install INSTALL_HDR_PATH=$pdir/usr

	# move asm headers to /usr/include/<libc-machine>/asm to match the structure
	# used by Debian-based distros (to support multi-arch)
	host_arch=$(dpkg-architecture -a$(cat debian/arch) -qDEB_HOST_MULTIARCH)
	mkdir $pdir/usr/include/$host_arch
	mv $pdir/usr/include/asm $pdir/usr/include/$host_arch/
}

version=$KERNELRELEASE
tmpdir=debian/linux-image
dbg_dir=debian/linux-image-dbg
packagename=linux-image-$version
dbg_packagename=$packagename-dbg

if [ "$ARCH" = "um" ] ; then
	packagename=user-mode-linux-$version
fi

# Not all arches have the same installed path in debian
# XXX: have each arch Makefile export a variable of the canonical image install
# path instead
case $ARCH in
um)
	installed_image_path="usr/bin/linux-$version"
	;;
parisc|mips|powerpc)
	installed_image_path="boot/vmlinux-$version"
	;;
*)
	installed_image_path="boot/vmlinuz-$version"
esac

BUILD_DEBUG=$(if_enabled_echo CONFIG_DEBUG_INFO Yes)

# Setup the directory structure
rm -rf "$tmpdir" "$dbg_dir" debian/files
mkdir -m 755 -p "$tmpdir/DEBIAN"
mkdir -p "$tmpdir/lib" "$tmpdir/boot"

# Install the kernel
if [ "$ARCH" = "um" ] ; then
	mkdir -p "$tmpdir/usr/lib/uml/modules/$version" "$tmpdir/usr/bin" "$tmpdir/usr/share/doc/$packagename"
	cp System.map "$tmpdir/usr/lib/uml/modules/$version/System.map"
	cp $KCONFIG_CONFIG "$tmpdir/usr/share/doc/$packagename/config"
	gzip "$tmpdir/usr/share/doc/$packagename/config"
else
	cp System.map "$tmpdir/boot/System.map-$version"
	cp $KCONFIG_CONFIG "$tmpdir/boot/config-$version"
fi
cp "$($MAKE -s -f $srctree/Makefile image_name)" "$tmpdir/$installed_image_path"

if is_enabled CONFIG_OF_EARLY_FLATTREE; then
	# Only some architectures with OF support have this target
	if [ -d "${srctree}/arch/$SRCARCH/boot/dts" ]; then
		$MAKE -f $srctree/Makefile INSTALL_DTBS_PATH="$tmpdir/usr/lib/$packagename" dtbs_install
	fi
fi

if is_enabled CONFIG_MODULES; then
	INSTALL_MOD_PATH="$tmpdir" $MAKE -f $srctree/Makefile modules_install
	rm -f "$tmpdir/lib/modules/$version/build"
	rm -f "$tmpdir/lib/modules/$version/source"
	if [ "$ARCH" = "um" ] ; then
		mv "$tmpdir/lib/modules/$version"/* "$tmpdir/usr/lib/uml/modules/$version/"
		rmdir "$tmpdir/lib/modules/$version"
	fi
	if [ -n "$BUILD_DEBUG" ] ; then
		for module in $(find $tmpdir/lib/modules/ -name *.ko -printf '%P\n'); do
			module=lib/modules/$module
			mkdir -p $(dirname $dbg_dir/usr/lib/debug/$module)
			# only keep debug symbols in the debug file
			$OBJCOPY --only-keep-debug $tmpdir/$module $dbg_dir/usr/lib/debug/$module
			# strip original module from debug symbols
			$OBJCOPY --strip-debug $tmpdir/$module
			# then add a link to those
			$OBJCOPY --add-gnu-debuglink=$dbg_dir/usr/lib/debug/$module $tmpdir/$module
		done

		# resign stripped modules
		if is_enabled CONFIG_MODULE_SIG_ALL; then
			INSTALL_MOD_PATH="$tmpdir" $MAKE -f $srctree/Makefile modules_sign
		fi
	fi
fi

# Install the maintainer scripts
# Note: hook scripts under /etc/kernel are also executed by official Debian
# kernel packages, as well as kernel packages built using make-kpkg.
# make-kpkg sets $INITRD to indicate whether an initramfs is wanted, and
# so do we; recent versions of dracut and initramfs-tools will obey this.
debhookdir=${KDEB_HOOKDIR:-/etc/kernel}
for script in postinst postrm preinst prerm ; do
	mkdir -p "$tmpdir$debhookdir/$script.d"
	cat <<EOF > "$tmpdir/DEBIAN/$script"
#!/bin/sh

set -e

# Pass maintainer script parameters to hook scripts
export DEB_MAINT_PARAMS="\$*"

# Tell initramfs builder whether it's wanted
export INITRD=$(if_enabled_echo CONFIG_BLK_DEV_INITRD Yes No)

test -d $debhookdir/$script.d && run-parts --arg="$version" --arg="/$installed_image_path" $debhookdir/$script.d
exit 0
EOF
	chmod 755 "$tmpdir/DEBIAN/$script"
done

if [ "$ARCH" != "um" ]; then
	if is_enabled CONFIG_MODULES; then
		deploy_kernel_headers debian/linux-headers
		create_package linux-headers-$version debian/linux-headers
	fi

	deploy_libc_headers debian/linux-libc-dev
	create_package linux-libc-dev debian/linux-libc-dev
fi

create_package "$packagename" "$tmpdir"

if [ -n "$BUILD_DEBUG" ] ; then
	# Build debug package
	# Different tools want the image in different locations
	# perf
	mkdir -p $dbg_dir/usr/lib/debug/lib/modules/$version/
	cp vmlinux $dbg_dir/usr/lib/debug/lib/modules/$version/
	# systemtap
	mkdir -p $dbg_dir/usr/lib/debug/boot/
	ln -s ../lib/modules/$version/vmlinux $dbg_dir/usr/lib/debug/boot/vmlinux-$version
	# kdump-tools
	ln -s lib/modules/$version/vmlinux $dbg_dir/usr/lib/debug/vmlinux-$version
	create_package "$dbg_packagename" "$dbg_dir"
fi

exit 0