TH_CWR
if (f & TH_CWR)
switch (tiflags & (TH_ACK|TH_ECE|TH_CWR)) {
case TH_ECE|TH_CWR:
tiflags &= ~(TH_ECE|TH_CWR);
if ((tiflags & TH_CWR)) {
if (do_ecn && (th->th_flags & (TH_ECE|TH_CWR)) == (TH_ECE|TH_CWR))
(tiflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ECE|TH_CWR|TH_ACK)) == TH_ACK &&
flags |= (TH_ECE|TH_CWR);
flags |= TH_CWR;
TH_ECNECHO|TH_CWR)) {
if (flags & TH_CWR)
#ifndef TH_CWR