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

exp_rtl_fetch_url_git() {
	local _tgtdir="${1}" _subdir="${2}" _url="${3}" _branch="${4}"	\
		_oldpwd="";
	(set -o errexit -o noglob; trap "rm -f \"${BUILD_DLCACHEDIR}/${_subdir%%[/]}.fetching\"" EXIT;
	while true; do
		if flock -E 622 -w 3600 4; then
			break;
		elif [ "${?}" -eq 622 ]; then
			continue;
		else
			exit "${?}";
		fi;
	done;
	if [ -e "${BUILD_DLCACHEDIR}/${_subdir}" ]; then
		(ex_rtl_fileop cd "${BUILD_DLCACHEDIR}/${_subdir}" &&\
			git pull ${DEFAULT_GIT_ARGS} origin "${_branch:-main}");
		(ex_rtl_fileop cd "${BUILD_DLCACHEDIR}/${_subdir}" &&\
			git submodule update);
	else
		git clone ${DEFAULT_GIT_ARGS} "${_url}" "${BUILD_DLCACHEDIR}/${_subdir}";
		if [ -n "${_branch}" ]; then
			(ex_rtl_fileop cd "${BUILD_DLCACHEDIR}/${_subdir}" &&\
				git checkout "${_branch}");
		fi;
		(ex_rtl_fileop cd "${BUILD_DLCACHEDIR}/${_subdir}" &&\
			git submodule update --init);
	fi;
	_oldpwd="${PWD}"; ex_rtl_fileop cd "${PKG_BASE_DIR}";
	ex_rtl_fileop rm "${_tgtdir}/${_subdir}";
	ex_rtl_fileop cp "${BUILD_DLCACHEDIR}/${_subdir}" "${_tgtdir}";
	ex_rtl_fileop cd "${_oldpwd}";) 4<>"${BUILD_DLCACHEDIR}/${_subdir%%[/]}.fetching";
	if [ "${?}" -eq 0 ]; then
		cd "$(pwd)";
	else
		return "${?}";
	fi;
};

ex_rtl_fetch_urls_git() {
	local _tgtdir="" _url_spec="" _subdir="" _url="" _git_branch="";
	_tgtdir="${1}"; shift;
	if [ "${ARG_FETCH_FORCE}" = "offline" ]; then
		return 0;
	fi;
	for _url_spec in "${@}"; do
		_subdir="${_url_spec%=*}";
		_url="${_url_spec#*=}";
		_url="${_url%@*}";
		if [ "${_url_spec#*@}" != "${_url_spec}" ]; then
			_git_branch=${_url_spec#*@};
		fi;
		exp_rtl_fetch_url_git "${_tgtdir}" "${_subdir}"	\
			"${_url}" "${_git_branch}";
	done;
};

# N.B.	URLs ($1) may contain `?' or '&' characters.
ex_rtl_fetch_url_wget() {
	local _url="${1}" _sha256sum_src="${2}" _target_fname="${3}" _sha256sum_dst="";
	if [ "${ARG_FETCH_FORCE}" = "offline" ]; then
		return 0;
	elif [ -z "${_target_fname}" ]; then
		_target_fname="$(ex_rtl_basename "${_url}")";
	fi;
	_url_dst="${BUILD_DLCACHEDIR}/${_target_fname}";
	(set -o errexit -o noglob; trap "_rc=\"\${?}\" ;rm -f \"${_url_dst}.fetching\"; exit \"\${_rc}\";" EXIT;
	while true; do
		if flock -E 622 -w 3600 4; then
			break;
		elif [ "${?}" -eq 622 ]; then
			continue;
		else
			exit "${?}";
		fi;
	done;
	if [ ! -e "${_url_dst}.fetched" ]; then
		wget ${DEFAULT_WGET_ARGS} -O "${_url_dst}" "${_url}";
		if [ -n "${_sha256sum_src}" ]; then
			set -- $(sha256sum "${_url_dst}");
			if [ "${_sha256sum_dst:=${1}}" != "${_sha256sum_src}" ]; then
				ex_rtl_log_msg failexit "Error: hash mismatch for URL \`${_url}' (downloaded file: ${_sha256sum_dst}, from build variables: ${_sha256sum_src}.)";
			fi;
		fi;
		ex_rtl_fileop touch "${_url_dst}.fetched";
	fi;) 4<>"${_url_dst}.fetching";
};

# vim:filetype=sh