#
# set -o noglob is assumed.
# WARNING: ex_pkg_dispatch(), its caller, and its callers must _NOT_ be executed
# as part of conditional evaluation, e.g. if, until, while, !, or && and ||, as
# doing so would inhibit set -o errexit during execution of this function and its
# subshell(!).  Instead, call ex_pkg_dispatch() and subsequently evaluate ${?}.
#

ex_pkg_dispatch() {
	local _tgt_name="${1}" _restart="${2}" _restart_at="${3}"		\
		_dispatch_fn="${4}" _tgt_name_uc				\
		_pkg_names _njob _njobs _njobs_max _pkg_name _pkg_name_uc	\
		_pipe_path _stderrout_path _pipe_msg _script_rc;
	ex_rtl_fileop mkdir "${BUILD_WORKDIR}";
	_pipe_path="${BUILD_WORKDIR}/build.fifo";
	_tgt_name_uc="$(ex_rtl_toupper "${_tgt_name}")";
	"${_dispatch_fn}" start_target "" "${_tgt_name}";
	_pkg_names="$(ex_rtl_get_var_unsafe ${_tgt_name_uc}_PACKAGES)";
	if [ -n "${_restart}" ]\
	&& [ "${_restart}" != ALL ]; then
		_pkg_names="$(ex_rtl_lfilter "${_pkg_names}" "${_restart}")";
	fi;
	set -- ${_pkg_names};
	while [ ${#} -gt 0 ]; do
		_script_rc=0; _njobs=0;
		if [ "$(ex_rtl_get_var_unsafe ${_tgt_name_uc}_PARALLELISE)" = 1 ]; then
			_njobs_max="${DEFAULT_BUILD_CPUS}";
		else
			_njobs_max=1;
		fi;
		ex_rtl_fileop mkfifo "${_pipe_path}";
		for _njob in $(seq 1 ${_njobs_max}); do
			if [ ${#} -eq 0 ]; then
				break;
			else
				_pkg_name="${1}"; shift;
				_pkg_name_uc="$(ex_rtl_toupper "${_pkg_name}")";
			fi;
			if [ -n "$(ex_rtl_get_var_unsafe PKG_${_pkg_name_uc}_DISABLED)" ]; then
				"${_dispatch_fn}" disabled_pkg "${_pkg_name}" "${_tgt_name}";
				continue;
			elif ex_pkg_state_test "${_pkg_name}" finish\
			&& [ -z "${_restart_at}" ]; then
				"${_dispatch_fn}" skipped_pkg "${_pkg_name}" "${_tgt_name}";
				continue;
			else
				_stderrout_path="${BUILD_WORKDIR}/${_pkg_name}_stderrout.log";
				"${_dispatch_fn}" start_pkg "${_pkg_name}" "${_tgt_name}";
			fi;
			(set -o errexit -o noglob;
			ex_pkg_env "${_pkg_name}" "${_tgt_name}" "${_restart_at}";
			trap "if [ \${?} -eq 0 ]; then					\
				echo \"done ${_pkg_name} ${_tgt_name}\" >&3;		\
			      else							\
				echo \"fail ${_pkg_name} ${_tgt_name}\" >&3;		\
			      fi;" EXIT HUP INT TERM USR1 USR2;
			ex_pkg_exec "${_pkg_name}" "${_tgt_name}" "${_restart_at}"	\
				"${_dispatch_fn}";) 1>"${_stderrout_path}" 2>&1 3>"${_pipe_path}" &
			: $((_njobs+=1));
		done;
		if [ "${_njobs:-0}" -gt 0 ]; then
			while read _pipe_msg; do
			case "${_pipe_msg%% *}" in
			done)	"${_dispatch_fn}" finish_pkg ${_pipe_msg#done };
				[ $((_njobs-=1)) -eq 0 ] && break; ;;
			fail)	_script_rc=1;
				"${_dispatch_fn}" fail_pkg ${_pipe_msg#fail };
				[ $((_njobs-=1)) -eq 0 ] && break; ;;
			step)	"${_dispatch_fn}" step_pkg ${_pipe_msg#step };
			esac; done <"${_pipe_path}";
			if [ "${_script_rc:-1}" -eq 1 ]; then
				ex_rtl_fileop rm "${_pipe_path}";
				return 1;
			fi;
		fi;
		ex_rtl_fileop rm "${_pipe_path}";
	done;
	"${_dispatch_fn}" finish_target "" "${_tgt_name}";
};

# vim:filetype=sh