TCPOLEN_SACK
#define TCPOLEN_MINSACK (TCPOLEN_SACK + 2)
for (i = 2; i + TCPOLEN_SACK <= safelen; i += TCPOLEN_SACK) {
if (optlen <= 2 || (optlen - 2) % TCPOLEN_SACK != 0)
tmp_olen -= TCPOLEN_SACK;
tmp_cp += TCPOLEN_SACK;
int maxsack = (MAX_TCPOPTLEN - (optlen + 4))/TCPOLEN_SACK;
*olp = htonl(TCPOPT_SACK_HDR|(TCPOLEN_SACK*count+2));
optlen += TCPOLEN_SACK*count + 4; /* including leading NOPs */
if ((datalen % TCPOLEN_SACK) != 0 ||
printf("sack %d ", datalen/TCPOLEN_SACK);
for (i = 0; i < datalen; i += TCPOLEN_SACK) {
LENCHECK (i + TCPOLEN_SACK);
#ifndef TCPOLEN_SACK