fsck: detect submodule urls starting with dash

Urls with leading dashes can cause mischief on older
versions of Git. We should detect them so that they can be
rejected by receive.fsckObjects, preventing modern versions
of git from being a vector by which attacks can spread.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
void fsck_set_msg_type(struct fsck_options *options,
		const char *msg_id, const char *msg_type)
{
	int id = parse_msg_id(msg_id), type;

	if (id < 0)
		die("Unhandled message id: %s", msg_id);
	type = parse_msg_type(msg_type);

	if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
		die("Cannot demote %s to %s", msg_id, msg_type);

	if (!options->msg_type) {
		int i;
		int *msg_type;
		ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
		for (i = 0; i < FSCK_MSG_MAX; i++)
			msg_type[i] = fsck_msg_type(i, options);
		options->msg_type = msg_type;
	}

	options->msg_type[id] = type;
}

void fsck_set_msg_type(struct fsck_options *options,
		const char *msg_id, const char *msg_type)
{
	int id = parse_msg_id(msg_id), type;

	if (id < 0)
		die("Unhandled message id: %s", msg_id);
	type = parse_msg_type(msg_type);

	if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
		die("Cannot demote %s to %s", msg_id, msg_type);

	if (!options->msg_type) {
		int i;
		int *msg_type;
		ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
		for (i = 0; i < FSCK_MSG_MAX; i++)
			msg_type[i] = fsck_msg_type(i, options);
		options->msg_type = msg_type;
	}

	options->msg_type[id] = type;
}
