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

rtl_check_path_vars() {
	local _vnames="${1}" _rc=0 _vname="" _vname_val=""; _status="";
	for _vname in ${_vnames}; do
		_vname_val="$(rtl_get_var_unsafe "${_vname}")";
		if [ -z "${_vname_val}" ]; then
			_rc=1; _status="Error: variable \`${_vname}' is empty or unset."; break;
		elif [ "${_vname_val#* *}" != "${_vname_val}" ]; then
			_rc=2; _status="Error: variable \`${_vname}' contains one or more whitespace characters."; break;
		fi;
	done;
	return "${_rc}";
};

rtl_clean_env() {
	local _env_vars_except="${1}" _env_var="" _env_vars="";
	_env_vars="$(export | sed -ne '/^export/{s/^export //;s/=.*$//p}')";
	for _env_var in ${_env_vars}; do
		if [ "${_env_var#DEFAULT_}" != "${_env_var}" ]\
		|| [ "${_env_var#PKG_}" != "${_env_var}" ]; then
			_env_vars_except="$(rtl_lconcat "${_env_vars_except}" "${_env_var}")";
		fi;
	done;
	rtl_unset_vars $(rtl_lfilter "${_env_vars}" "${_env_vars_except}");
};

rtl_exists_any() {
	local _subdir="${1}"; shift;
	while [ "${#}" -gt 0 ]; do
		if [ -e "${_subdir}/${1}" ]; then
			return 0;
		else
			shift;
		fi;
	done; return 1;
};

rtl_export_vars() {
	local _unsetfl=0; [ "x${1}" = "x-u" ] && { _unsetfl=1; shift; };
	while [ "${#}" -ge 2 ]; do
		if [ -n "${2}" ]; then
			if [ "${_unsetfl:-0}" -eq 0 ]; then
				rtl_set_var_unsafe "${1}" "${2}"; export "${1}";
			else
				unset "${1}";
			fi;
		fi;
		shift 2;
	done;
};

rtl_get_var_unsafe() {
	local _vname="";
	if [ "x${1}" = "x-u" ]; then
		shift; _vname="$(rtl_toupper "${1}")";
	else
		_vname="${1}";
	fi;
	eval echo \${${_vname}};
};

rtl_head() {
	local _pattern="${1}" _s="${2}";
	while true; do
		if [ "${_s%%${_pattern}}" = "${_s}" ]; then
			break;
		else
			_s="${_s%%${_pattern}}";
		fi;
	done;
	echo "${_s}";
};

rtl_kill_tree() {
	local _pid="${1}" _signal="${2:-TERM}" _pid_child="" _pids="";
	if _pids="$(pgrep -P "${_pid}")"\
	&& [ -n "${_pids}" ]; then
		for _pid_child in ${_pids}; do
			rtl_kill_tree "${_pid_child}" "${_signal}";
		done;
	fi;
	if [ "${_pid:-0}" -ne "${$}" ]\
	&& kill "-${_signal}" "${_pid}" 2>/dev/null; then
		RTL_KILL_TREE_PIDS="$(rtl_lconcat "${RTL_KILL_TREE_PIDS}" "${_pid}")";
	fi;
};

rtl_run_cmd_unsplit() {
	local _cmd="${1}" _cmdline="" _rc="" IFS; shift;
	while [ ${#} -gt 0 ]; do
		[ -n "${1}" ] &&\
			_cmdline="${_cmdline:+${_cmdline}:}${1}";
		shift;
	done;
	IFS=:; ${_cmd} ${_cmdline}; _rc=$?;
	return ${_rc};
};

rtl_set_vars() {
	local	_vars_set_vname="${1}" _vname_dst="${2}" _vname_src_tmpls="${3}"	\
		_vars_set_old="" _vars_set_tmp="" _vname_src="";
	for _vname_src in $(rtl_toupper "${_vname_src_tmpls}"); do
		_vname_src="${_vname_src}_${_vname_dst}";
		_vval_src="$(rtl_get_var_unsafe "${_vname_src}")";
		if [ -n "${_vval_src}" ]; then
			rtl_set_var_unsafe "PKG_${_vname_dst}" "${_vval_src}";
			_vars_set_tmp="$(rtl_lconcat "${_vars_set_tmp}" "PKG_${_vname_dst}")";
		fi;
	done;
	_vars_set_old="$(rtl_get_var_unsafe "${_vars_set_vname}")";
	rtl_set_var_unsafe "${_vars_set_vname}"					\
		"$(rtl_lconcat "${_vars_set_old}" "${_vars_set_tmp}")";
};

# vim:filetype=sh