rem: return dw_strcasecmp(s1, len1, s2, len2);
add: return dw_strasciicasecmp(s1, len1, s2, len2);
context: int DwStrncasecmp(const DwString& aStr1, const DwString& aStr2, size_t n){    const char* s1 = aStr1.data();    size_t len1 = aStr1.length();    len1 = DW_MIN(len1, n);    const char* s2 = aStr2.data();    size_t len2 = aStr2.length();    len2 = DW_MIN(len2, n);    return dw_strcasecmp(s1, len1, s2, len2);}