BUILD_ARGS_SPEC="
	ARG_IPV4_ONLY:-4
	ARG_IPV6_ONLY:-6
	ARCH:arg:-a
	BUILD:arg:-b
	ARG_CLEAN:-c
	ARG_DEBUG_MINIPIX:--debug-minipix
	ARG_IGNORE_SHA256SUMS:-i
	ARG_OFFLINE:-N
	ARG_RELAXED:-R
	ARG_RESTART:arg:-r
	ARG_TARBALL:selfarg:-t
	ARG_TARBALL:selfarg:-t.bz2
	ARG_TARBALL:selfarg:-t.gz
	ARG_TARBALL:selfarg:-t.xz
	ARG_VERBOSE:-v
	ARG_XTRACE:-x";

pre_setup_args() {
	local _spec="${BUILD_ARGS_SPEC}" _spec_arg _found;
	while [ ${#} -gt 0 ]; do
		if [ "${1#-}" = "${1}" ]; then
			break;
		fi;
		for _spec_arg in ${_spec}; do
			case "${_spec_arg}" in
			*:${1})	case "${_spec_arg#*:}" in
				arg:*)
					set_var_unsafe "${_spec_arg%%:*}" "${2}"; shift; ;;
				selfarg:*)
					set_var_unsafe "${_spec_arg%%:*}" "${1}"; ;;
				*)
					set_var_unsafe "${_spec_arg%%:*}" 1; ;;
				esac; _found=1; break; ;;
			*)	_found=0; ;;
			esac;
		done;
		if [ "${_found:-0}" -eq 0 ]; then
			exec cat etc/build.usage;
		else
			shift;
		fi;
	done;
	if [ -n "${ARG_TARBALL}" ]; then
		if [ "${ARG_TARBALL#-t.}" != "${ARG_TARBALL}" ]; then
			TARBALL_SUFFIX="${ARG_TARBALL#-t.}";
		else
			TARBALL_SUFFIX=xz;
		fi;
	fi;
	if [ "${ARG_XTRACE:-0}" -eq 1 ]; then
		set -o xtrace;
	fi;
	if [ -n "${ARG_RESTART}" ]; then
		if [ "${ARG_RESTART%:*}" != "${ARG_RESTART}" ]; then
			ARG_RESTART_AT="${ARG_RESTART#*:}"; ARG_RESTART="${ARG_RESTART%:*}";
		fi;
		BUILD_PACKAGES_RESTART="$(echo ${ARG_RESTART} | sed "s/,/ /g")";
	fi;
	while [ ${#} -gt 0 ]; do
	case "${1}" in
	*=*)	set_var_unsafe "${1%%=*}" "${1#*=}"; ;;
	*)	BUILD_TARGETS_META="${BUILD_TARGETS_META:+${BUILD_TARGETS_META} }${1}"; ;;
	esac; shift; done;
};

# vim:filetype=sh