SIP_URI_ISALNUM
if (scan < uend && SIP_URI_ISALNUM(*scan)) {
} while (scan < uend && SIP_URI_ISALNUM(*scan));
while (scan < uend && (*scan == '-'|| SIP_URI_ISALNUM(*scan)))
!SIP_URI_ISALPHA(*mark) || !SIP_URI_ISALNUM(*(scan - 1))) {