#

# set +o errexit -o noglob -o nounset is assumed.

#

rtl_export_vars() {

	local _rev_unsetfl=0;

	if [ "x${1}" = "x-u" ]; then

		_rev_unsetfl=1; shift;

	fi;

	while [ "${#}" -ge 2 ]; do

		if [ "${2:+1}" = 1 ]\

		|| [ "${_rev_unsetfl}" -eq 1 ]; then

			case "${_rev_unsetfl}" in

			0)	rtl_set_var_unsafe "${1}" "${2}";

				export "${1}"; ;;

			1)	unset "${1}"; ;;

			esac;

		fi; shift 2;

	done;

	return 0;

};

rtl_head() {

	local _rh_pattern="${1}" _rh_s="${2}" _rh_rs_out="${3#\$}";

	while true; do

		if [ "${_rh_s%%${_rh_pattern}}" = "${_rh_s}" ]; then

			break;

		else

			_rh_s="${_rh_s%%${_rh_pattern}}";

		fi;

	done;

	eval ${_rh_rs_out}='${_rh_s}';

	return 0;

};

rtl_percentage() {

	local	_rp_in="${1}" _rp_max="${2}" _rp_rs_out="${3#\$}"	\

		_rp_perc;

	_rp_perc=$((100 * ${_rp_in} + ${_rp_max} / 2));

	_rp_perc=$((${_rp_perc} ? ${_rp_perc} / ${_rp_max} : ${_rp_perc}));

	eval ${_rp_rs_out}='${_rp_perc}';

	return 0;

};

rtl_percentage2() {

	local	_rp_rin="${1#\$}" _rp_rmax="${2#\$}" _rp_rs_out="${3#\$}"	\

		_rp_in=0 _rp_max=0 _rp_perc;

	eval _rp_in=\"\${${_rp_rin}}\";

	eval _rp_max=\"\${${_rp_rmax}}\";

	_rp_perc=$((100 * ${_rp_in} + ${_rp_max} / 2));

	_rp_perc=$((${_rp_perc} ? ${_rp_perc} / ${_rp_max} : ${_rp_perc}));

	eval ${_rp_rs_out}='${_rp_perc}';

	return 0;

};

rtl_sunset() {

	local _rs_rset="${1#\$}" _rs_kname="" IFS=" 	";

	eval set -- "\${${_rs_rset}}";

	while [ "${#}" -gt 0 ]; do

		unset "${_rs_rset}${_rs_kname}"; shift;

	done; unset "${_rs_rset}";

	return 0;

};

# vim:filetype=sh textwidth=0