UTF8_getc
ret = UTF8_getc(p, len, &value);
i = UTF8_getc(p, buflen, &c);
j = UTF8_getc((const unsigned char *)asc + i, asclen - i, &utf32chr);
j = UTF8_getc((const unsigned char *)asc + i, asclen - i, &utf32chr);
int UTF8_getc(const unsigned char *str, int len, unsigned long *val);
if (!TEST_int_lt(UTF8_getc(inv_utf8, sizeof(inv_utf8), &val), 0))