#!@SH@
#
# opkhelper
# src/oh-strip.sh
# Strip binary objects of symbols.
#
# Copyright (C) 2012  Patrick "P. J." McDermott
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

. '@pkgdatadir@/load.sm'

CR='
'
KEEP_DEBUG='false'

main()
{
	dir='dest'

	oh_init

	while getopts 'd:k' opt; do
		case "${opt}" in
			d)
				dir="${OPTARG}"
				;;
			k)
				KEEP_DEBUG='true'
				;;
			?)
				oh_error "$(oh_get_msg 'bad_opt')"
				exit 1
				;;
		esac
	done

	find "${dir}" -type f -a ! -path '*/debug/*' -a -name '*.so*' | \
		while IFS="${CR}" read file; do
			if file "${file}" | grep 'ELF.*shared' \
					>/dev/null 2>&1; then
				file="${file#${dir}}"
				file="/${file##/}"
				strip_so "${file}"
			fi
		done

	find "${dir}" -type f -a ! -path '*/debug/*' -a -perm '-a+x' | \
		while IFS="${CR}" read file; do
			if file "${file}" | grep -E 'ELF.*(executable|shared)' \
					>/dev/null 2>&1; then
				file="${file#${dir}}"
				file="/${file##/}"
				strip_exe "${file}"
			fi
		done

	find "${dir}" -type f -a ! -path '*/debug/*' -a -name 'lib*.a' \
		-a ! -name '*_g.a' | while IFS="{CR}" read file; do
			file="${file#${dir}}"
			file="/${file##/}"
			strip_a "${file}"
		done
}

strip_so()
{
	file="${1}"
	debug=''

	oh_info "$(oh_get_msg 'strip_so')" "${file}"

	if ${KEEP_DEBUG}; then
		debug="$(keep_debug "${file}")"
	fi

	${STRIP} --remove-section=.comment --remove-section=.note \
		--strip-unneeded "${dir}/${file}"

	if [ -n "${debug}" ]; then
		link_debug "${file}" "${debug}"
	fi
}

strip_exe()
{
	file="${1}"
	debug=''

	oh_info "$(oh_get_msg 'strip_exe')" "${file}"

	if ${KEEP_DEBUG}; then
		debug="$(keep_debug "${file}")"
	fi

	${STRIP} --remove-section=.comment --remove-section=.note \
		"${dir}/${file}"

	if [ -n "${debug}" ]; then
		link_debug "${file}" "${debug}"
	fi
}

strip_a()
{
	file="${1}"

	oh_info "$(oh_get_msg 'strip_a')" "${file}"

	${STRIP} --strip-debug "${dir}/${file}"
}

keep_debug()
{
	file="${1}"
	build_id_parts=''
	debug=''

	if ! file "${dir}/${file}" | grep 'not stripped' >/dev/null 2>&1; then
		return
	fi

	build_id_parts="$(${READELF} -n "${dir}/${file}" | sed -n \
		's/^.*Build ID: \([0-9a-f][0-9a-f]\)\([0-9a-f]*\)$/\1 \2/p')"
	if [ -z "${build_id_parts}" ]; then
		return
	fi

	debug="/usr/lib/debug/.build-id/${build_id_parts% *}"
	debug="${debug}/${build_id_parts#* }.debug"

	mkdir -p "${dir}/${debug%/*}"

	${OBJCOPY} --only-keep-debug --compress-debug-sections \
		"${dir}/${file}" "${dir}/${debug}"
	chmod 644 "${dir}/${debug}"

	printf '%s\n' "${debug}"
}

link_debug()
{
	file="${1}"
	debug="${2}"

	${OBJCOPY} --add-gnu-debuglink="${dir}/${debug}" "${dir}/${file}"
}

main "${@}"