Function is_urlschemechar

url.c:19–32

}

int is_urlschemechar(int first_flag, int ch)
{
	/*
	 * The set of valid URL schemes, as per STD66 (RFC3986) is
	 * '[A-Za-z][A-Za-z0-9+.-]*'. But use slightly looser check
	 * of '[A-Za-z0-9][A-Za-z0-9+.-]*' because earlier version
	 * of check used '[A-Za-z0-9]+' so not to break any remote
	 * helpers.
	 */
	int alphanumeric, special;
	alphanumeric = ch > 0 && isalnum(ch);
	special = ch == '+' || ch == '-' || ch == '.';
	return alphanumeric || (!first_flag && special);
}

int is_url(const char *url)
{