#

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

#

rtl_check_prereqs() {

	local _cmd="" _cmds_missing="" _rc=0; _status="";

	for _cmd in "${@}"; do

		if ! which "${_cmd}" >/dev/null 2>&1; then

			_cmds_missing="${_cmds_missing:+${_cmds_missing} }${_cmd}";

		fi;

	done;

	if [ -n "${_cmds_missing}" ]; then

		_rc=1; _status="Error: missing prerequisite package(s): ${_cmds_missing}";

	fi;

	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_get_cpu_count() {

	local _line="" _ncpus=0 _rc=0 _sname="$(uname -s 2>/dev/null)"; _status="";

	case "${_sname}" in

	Linux)	if [ ! -e "/proc/cpuinfo" ]; then

			_rc=1; _status="Error: /proc/cpuinfo non-existent.";

		else	while read -r _line; do

				if rtl_match "${_line}" "processor*:"; then

					: $((_ncpus+=1));

				fi;

			done < /proc/cpuinfo; printf "%s" "${_ncpus}";

		fi; ;;

	*)	_rc=1; _status="Error: unknown platform \`${_sname}'."; ;;

	esac; return "${_rc}";

};

rtl_get_var_unsafe() {

	local _vname="";

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

		shift; _vname="$(rtl_toupper "${1}")";

	else

		_vname="${1}";

	fi;

	eval echo \${${_vname}} 2>/dev/null;

};

rtl_get_vars_fast() {

	local _pattern="${1}";

	set | awk -F= '/'"${_pattern}"'/{print $1}' | sort;

};

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_prompt() {

	local _fmt="${1}" _choice=""; shift;

	printf "${_fmt}? (y|N) " "${@}";

	read -r _choice;

	case "${_choice}" in

	[yY])	_choice=1; ;;

	*)	_choice=0; ;;

	esac;

	return "${_choice}";

};

rtl_rc() {

	local _nflag="${1}" _cmd="${2}"; shift 2;

	case "${_nflag}" in

	1)	     if [ "${#}" -gt 0 ]; then

			rtl_log_msg "verbose" "Command line: %s %s" "${_cmd}" "${*}";

		else

			rtl_log_msg "verbose" "Command line: %s" "${_cmd}";

		fi; ;;

	*)	"${_cmd}" "${@}";

	esac;

};

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}";

		eval _vval_src='${'"${_vname_src}"':-}';

		if [ "${_vval_src:+1}" = 1 ]; then

			eval PKG_${_vname_dst}='${_vval_src}';

			_vars_set_tmp="${_vars_set_tmp:+${_vars_set_tmp} }PKG_${_vname_dst}";

		fi;

	done;

	eval _vars_set_old='${'"${_vars_set_vname}"'}';

	rtl_set_var_unsafe "${_vars_set_vname}" "${_vars_set_old:+${_vars_set_old} }${_vars_set_tmp}";

};

# vim:filetype=sh