UTF8_STACKBUF
uint8_t bytes[UTF8_STACKBUF] = { 0 };
int curidx = UTF8_STACKBUF - 1, cwidth = 1,
while (CTL_UTF8_CONT(c) && nb < UTF8_STACKBUF) {
if (nb < UTF8_STACKBUF)
if (nb == UTF8_STACKBUF &&
UTF8_STACKBUF, 0);