#

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

#

# N.B.	URLs ($1) may contain `?' or '&' characters.

rtl_fetch_url_wget() {

	local _urls="${1}" _sha256sum_src="${2}" _target_dname="${3}" _target_fname="${4}" _target_name="${5}" _mirrors="${6:-}"\

		_rc=0 _sha256sum_target="" _target_fname_full="" _url="" _url_base="" _urls_count=0 _urls_full="";

	_urls_full="${_urls}";

	for _url_base in ${_mirrors}; do

		_urls_full="$(rtl_lconcat "${_urls_full}" "${_url_base%/}/${_target_name}/${_target_fname}")";

	done;

	_urls_count="$(rtl_llength "${_urls_full}")";

	for _url in ${_urls_full}; do

		if [ -z "${_target_fname}" ]; then

			_target_fname="$(rtl_basename "${_url}")";

		fi;

		_target_fname_full="${_target_dname}/${_target_fname}";

		(set +o errexit -o noglob -o nounset;

		rtl_flock_acquire 4 || exit 1;

		trap "_rc=\"\${?}\"; rm -f \"${_target_fname_full}.fetching\"; exit \"\${_rc}\";" EXIT;

		if [ -z "${_sha256sum_src}" ]\

		|| ! rtl_check_digest_file "${_target_fname_full}" "${_sha256sum_src}" "${_target_fname_full}.fetched"; then

			wget ${DEFAULT_WGET_ARGS} -O "${_target_fname_full}" "${_url}"; _rc="${?}";

			if [ "${_rc}" -ne 0 ]; then

				exit $((${_rc}+2));

			elif [ -n "${_sha256sum_src}" ]\

			&& ! rtl_check_digest "${_target_fname_full}" "${_sha256sum_src}"; then

				exit 2;

			else

				printf "%s" "${RTL_CHECK_DIGEST_DIGEST}" > "${_target_fname_full}.fetched"; exit 0;

			fi;

		else

			exit 0;

		fi;) 4<>"${_target_fname_full}.fetching"; _rc="${?}"; : $((_urls_count-=1));

		case "${_rc}" in

		0)	break; ;;

		1)	if [ "${_urls_count}" -ge 1 ]; then

				rtl_log_msg warning "Warning: failed to acquire fetching lock for URL \`%s', retrying with alternative URL..." "${_url}";

			else

				rtl_log_msg fatal "Error: failed to acquire fetching lock for URL \`%s'." "${_url}";

				rtl_fileop rm "${_target_fname_full}"; break;

			fi; ;;

		2)	if [ "${_urls_count}" -ge 1 ]; then

				rtl_log_msg warning "Warning: hash mismatch for URL \`%s', retrying with alternative URL... (from build variables: %s.)"\

						"${_url}" "${_sha256sum_src}";

			else

				if _sha256sum_target="$(sha256sum "${_target_fname_full}" |\

							awk '{print $1}' 2>/dev/null)"; then

					rtl_log_msg fatal "Error: hash mismatch for URL \`%s' (should be: %s vs.: %s.)"\

							"${_url}" "${_sha256sum_src}" "${_sha256sum_target}";

				else

					rtl_log_msg fatal "Error: hash mismatch for URL \`%s' (should be: %s.)"\

							"${_url}" "${_sha256sum_src}";

				fi;

				rtl_fileop rm "${_target_fname_full}"; break;

			fi; ;;

		*)	if [ "${_urls_count}" -ge 1 ]; then

				rtl_log_msg warning "Warning: failed to fetch URL \`%s', retrying with alternative URL... (wget(1) exit status: %s)"\

						"${_url}" "$((${_rc}-2))";

			else

				rtl_log_msg fatal "Error: failed to fetch URL \`%s' (wget(1) exit status: %s)"\

						"${_url}" "$((${_rc}-2))";

				rtl_fileop rm "${_target_fname_full}"; break;

			fi; ;;

		esac;

	done;

	return "${_rc}";

};

# vim:filetype=sh