# Copyright 1999-2015 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Id$

# XXX: we need to review menu.lst vs grub.conf handling.  We've been converting
#      all systems to grub.conf (and symlinking menu.lst to grub.conf), but
#      we never updated any of the source code (it still all wants menu.lst),
#      and there is no indication that upstream is making the transition.

# If you need to roll a new grub-static distfile, here is how.
# - Robin H. Johnson <robbat2@gentoo.org> - 29 Nov 2010
# FEATURES='-noauto -noinfo -nodoc -noman -splitdebug nostrip' \
# USE='static -ncurses -netboot -custom-cflags' \
# PORTAGE_COMPRESS=true GRUB_STATIC_PACKAGE_BUILDING=1 ebuild \
# grub-${PVR}.ebuild clean package && \
# qtbz2 -s -j ${PKGDIR}/${CAT}/${PF}.tbz2 && \
# mv ${PF}.tar.bz2 ${DISTDIR}/grub-static-${PVR}.tar.bz2

EAPI="5"

inherit eutils mount-boot toolchain-funcs linux-info flag-o-matic autotools pax-utils multiprocessing

PATCHVER="1.14" # Should match the revision ideally
DESCRIPTION="GNU GRUB Legacy boot loader"
HOMEPAGE="https://www.gnu.org/software/grub/"
SRC_URI="mirror://gentoo/${P}.tar.gz
	mirror://gnu-alpha/${PN}/${P}.tar.gz
	mirror://gentoo/splash.xpm.gz
	mirror://gentoo/${P}-patches-${PATCHVER}.tar.bz2"

LICENSE="GPL-2"
SLOT="0"
KEYWORDS="amd64 x86 ~x86-fbsd"
IUSE="custom-cflags ncurses netboot static"

LIB_DEPEND="ncurses? ( >=sys-libs/ncurses-5.9-r3:0[static-libs(+),abi_x86_32(-)] )"
RDEPEND="!static? ( ${LIB_DEPEND//[static-libs(+),/=[} )"
DEPEND="${RDEPEND}
	static? ( ${LIB_DEPEND} )"

pkg_setup() {
	case $(tc-arch) in
	amd64) CONFIG_CHECK='~IA32_EMULATION' check_extra_config ;;
	esac
}

src_prepare() {
	# Grub will not handle a kernel larger than EXTENDED_MEMSIZE Mb as
	# discovered in bug 160801. We can change this, however, using larger values
	# for this variable means that Grub needs more memory to run and boot. For a
	# kernel of size N, Grub needs (N+1)*2.  Advanced users should set a custom
	# value in make.conf, it is possible to make kernels ~16Mb in size, but it
	# needs the kitchen sink built-in.
	local t="custom"
	if [[ -z ${GRUB_MAX_KERNEL_SIZE} ]] ; then
		case $(tc-arch) in
		amd64) GRUB_MAX_KERNEL_SIZE=9 ;;
		x86)   GRUB_MAX_KERNEL_SIZE=5 ;;
		esac
		t="default"
	fi
	einfo "Grub will support the ${t} maximum kernel size of ${GRUB_MAX_KERNEL_SIZE} Mb (GRUB_MAX_KERNEL_SIZE)"

	sed -i \
		-e "/^#define.*EXTENDED_MEMSIZE/s,3,${GRUB_MAX_KERNEL_SIZE},g" \
		"${S}"/grub/asmstub.c \
		|| die

	EPATCH_SUFFIX="patch" epatch "${WORKDIR}"/patch

	# Work around issue where the default CFLAGS fail with gcc-4.9.3 (possibly newer), force -O0 instead
	# bug 564890, 566638
	if [[ $(gcc-major-version) -ge 5 || $(gcc-major-version) -eq 4 && $(gcc-minor-version) -ge 9 ]]; then
		if use custom-cflags; then
			ewarn "You are using custom cflags with gcc-4.9 or newer."
			ewarn "Be aware the result may segfault at runtime due to unknown optimization"
			ewarn "incompatibilities."
		else
			einfo "Forcing -O0 to get around optimization issue caused by gcc-4.9 and newer with -O2"
			sed -i	-e "/CFLAGS/s/-O2/-O0/" \
				"${S}"/configure.ac || die
		fi
	fi

	rm -f "${S}"/aclocal.m4 # seems to keep bug 418287 away
	eautoreconf
}

src_configure() {
	filter-flags -fPIE #168834

	use amd64 && multilib_toolchain_setup x86

	unset BLOCK_SIZE #73499

	### i686-specific code in the boot loader is a bad idea; disabling to ensure
	### at least some compatibility if the hard drive is moved to an older or
	### incompatible system.

	# grub-0.95 added -fno-stack-protector detection, to disable ssp for stage2,
	# but the objcopy's (faulty) test fails if -fstack-protector is default.
	# create a cache telling configure that objcopy is ok, and add -C to econf
	# to make use of the cache.
	#
	# CFLAGS has to be undefined running econf, else -fno-stack-protector detection fails.
	# STAGE2_CFLAGS is not allowed to be used on emake command-line, it overwrites
	# -fno-stack-protector detected by configure, removed from netboot's emake.
	use custom-cflags || unset CFLAGS

	tc-ld-disable-gold #439082 #466536 #526348

	export grub_cv_prog_objcopy_absolute=yes #79734
	use static && append-ldflags -static

	if use amd64 && use static ; then
		if [[ -n ${GRUB_STATIC_PACKAGE_BUILDING} ]] ; then
			eerror "You have set GRUB_STATIC_PACKAGE_BUILDING. This"
			eerror "is specifically intended for building the tarballs for the"
			eerror "grub-static package via USE='static -ncurses'."
			eerror "All bets are now off."
		fi
	fi

	multijob_init

	# build the net-bootable grub first, but only if "netboot" is set
	if use netboot ; then
		(
		multijob_child_init
		mkdir -p "${WORKDIR}"/netboot
		pushd "${WORKDIR}"/netboot >/dev/null
		ECONF_SOURCE=${S} \
		econf \
			--libdir=/lib \
			--datadir=/usr/lib/grub \
			--exec-prefix=/ \
			--disable-auto-linux-mem-opt \
			--enable-diskless \
			--enable-{3c{5{03,07,09,29,95},90x},cs89x0,davicom,depca,eepro{,100}} \
			--enable-{epic100,exos205,ni5210,lance,ne2100,ni{50,65}10,natsemi} \
			--enable-{ne,ns8390,wd,otulip,rtl8139,sis900,sk-g16,smc9000,tiara} \
			--enable-{tulip,via-rhine,w89c840}
		popd >/dev/null
		) &
		multijob_post_fork
	fi

	# Now build the regular grub
	# Note that FFS and UFS2 support are broken for now - stage1_5 files too big
	econf \
		--libdir=/lib \
		--datadir=/usr/lib/grub \
		--exec-prefix=/ \
		--disable-auto-linux-mem-opt \
		$(use_with ncurses curses)

	# sanity check due to common failure
	use ncurses && ! grep -qs "HAVE_LIBCURSES.*1" config.h && die "USE=ncurses but curses not found"

	multijob_finish
}

src_compile() {
	use netboot && emake -C "${WORKDIR}"/netboot w89c840_o_CFLAGS="-O"
	emake
}

src_test() {
	# non-default block size also give false pass/fails.
	unset BLOCK_SIZE
	emake -j1 check
}

src_install() {
	default
	if use netboot ; then
		exeinto /usr/lib/grub/${CHOST}
		doexe "${WORKDIR}"/netboot/stage2/{nbgrub,pxegrub}
		newexe "${WORKDIR}"/netboot/stage2/stage2 stage2.netboot
	fi

	pax-mark -m "${D}"/sbin/grub #330745

	newdoc docs/menu.lst grub.conf.sample
	dodoc "${FILESDIR}"/grub.conf.gentoo

	[[ -n ${GRUB_STATIC_PACKAGE_BUILDING} ]] && \
		mv "${D}"/usr/share/doc/{${PF},grub-static-${PF/grub-}}

	insinto /usr/share/grub
	doins "${DISTDIR}"/splash.xpm.gz
}

setup_boot_dir() {
	local boot_dir=$1
	local dir=${boot_dir}

	mkdir -p "${dir}"
	[[ ! -L ${dir}/boot ]] && ln -s . "${dir}/boot"
	dir="${dir}/grub"
	if [[ ! -e ${dir} ]] ; then
		mkdir "${dir}" || die
	fi

	# change menu.lst to grub.conf
	if [[ ! -e ${dir}/grub.conf ]] && [[ -e ${dir}/menu.lst ]] ; then
		mv -f "${dir}"/menu.lst "${dir}"/grub.conf
		ewarn "*** IMPORTANT NOTE: menu.lst has been renamed to grub.conf"
		echo
	fi

	if [[ ! -e ${dir}/menu.lst ]]; then
		einfo "Linking from new grub.conf name to menu.lst"
		ln -snf grub.conf "${dir}"/menu.lst
	fi

	if [[ -e ${dir}/stage2 ]] ; then
		mv "${dir}"/stage2{,.old}
		ewarn "*** IMPORTANT NOTE: you must run grub and install"
		ewarn "the new version's stage1 to your MBR.  Until you do,"
		ewarn "stage1 and stage2 will still be the old version, but"
		ewarn "later stages will be the new version, which could"
		ewarn "cause problems such as an unbootable system."
		ewarn
		ewarn "This means you must use either grub-install or perform"
		ewarn "root/setup manually."
		ewarn
		ewarn "For more help, see the handbook:"
		ewarn "https://www.gentoo.org/doc/en/handbook/handbook-${ARCH}.xml?part=1&chap=10#grub-install-auto"
		echo
	fi

	einfo "Copying files from /lib/grub and /usr/share/grub to ${dir}"
	for x in \
		"${ROOT}"/lib*/grub/*/* \
		"${ROOT}"/usr/share/grub/* ; do
		[[ -f ${x} ]] && cp -p "${x}" "${dir}"/
	done

	if [[ ! -e ${dir}/grub.conf ]] ; then
		s="${ROOT}/usr/share/doc/${PF}/grub.conf.gentoo"
		[[ -e "${s}" ]] && cat "${s}" >${dir}/grub.conf
		[[ -e "${s}.gz" ]] && zcat "${s}.gz" >${dir}/grub.conf
		[[ -e "${s}.bz2" ]] && bzcat "${s}.bz2" >${dir}/grub.conf
	fi

	# Per bug 218599, we support grub.conf.install for users that want to run a
	# specific set of Grub setup commands rather than the default ones.
	grub_config=${dir}/grub.conf.install
	[[ -e ${grub_config} ]] || grub_config=${dir}/grub.conf
	if [[ -e ${grub_config} ]] ; then
		egrep \
			-v '^[[:space:]]*(#|$|default|fallback|initrd|password|splashimage|timeout|title)' \
			"${grub_config}" | \
		/sbin/grub --batch \
			--device-map="${dir}"/device.map \
			> /dev/null
	fi

	# the grub default commands silently piss themselves if
	# the default file does not exist ahead of time
	if [[ ! -e ${dir}/default ]] ; then
		grub-set-default --root-directory="${boot_dir}" default
	fi
	einfo "Grub has been installed to ${boot_dir} successfully."
}

pkg_postinst() {
	mount-boot_mount_boot_partition

	if [[ -n ${DONT_MOUNT_BOOT} ]]; then
		elog "WARNING: you have DONT_MOUNT_BOOT in effect, so you must apply"
		elog "the following instructions for your /boot!"
		elog "Neglecting to do so may cause your system to fail to boot!"
		elog
	else
		setup_boot_dir "${ROOT}"/boot
		# Trailing output because if this is run from pkg_postinst, it gets mixed into
		# the other output.
		einfo ""
	fi
	elog "To interactively install grub files to another device such as a USB"
	elog "stick, just run the following and specify the directory as prompted:"
	elog "   emerge --config =${PF}"
	elog "Alternately, you can export GRUB_ALT_INSTALLDIR=/path/to/use to tell"
	elog "grub where to install in a non-interactive way."

	# needs to be after we call setup_boot_dir
	mount-boot_pkg_postinst
}

pkg_config() {
	local dir
	if [ ! -d "${GRUB_ALT_INSTALLDIR}" ]; then
		einfo "Enter the directory where you want to setup grub:"
		read dir
	else
		dir="${GRUB_ALT_INSTALLDIR}"
	fi
	setup_boot_dir "${dir}"
}