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>
static int parse_msg_type(const char *str)
{
	if (!strcmp(str, "error"))
		return FSCK_ERROR;
	else if (!strcmp(str, "warn"))
		return FSCK_WARN;
	else if (!strcmp(str, "ignore"))
		return FSCK_IGNORE;
	else
		die("Unknown fsck message type: '%s'", str);
}

static int parse_msg_type(const char *str)
{
	if (!strcmp(str, "error"))
		return FSCK_ERROR;
	else if (!strcmp(str, "warn"))
		return FSCK_WARN;
	else if (!strcmp(str, "ignore"))
		return FSCK_IGNORE;
	else
		die("Unknown fsck message type: '%s'", str);
}
