X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/3b35bf499f76e67f8f24afd8572a953ec82c4c18..795abf1316db53d4abdc5bff180f2b2376c5cfe4:/sys/netinet/tcp_input.c

diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c
index 7b07db2f6c..21f9df5138 100644
--- a/sys/netinet/tcp_input.c
+++ b/sys/netinet/tcp_input.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)tcp_input.c	7.25 (Berkeley) 6/30/90
- *	$Id: tcp_input.c,v 1.3 1993/11/25 01:35:13 wollman Exp $
+ *	$Id: tcp_input.c,v 1.8 1994/01/30 01:00:28 davidg Exp $
  */
 
 #include "param.h"
@@ -57,7 +57,9 @@
 #include "tcp_timer.h"
 #include "tcp_var.h"
 #include "tcpip.h"
+#ifdef TCPDEBUG
 #include "tcp_debug.h"
+#endif
 
 static void tcp_dooptions(struct tcpcb *, struct mbuf *, struct tcpiphdr *);
 static void tcp_pulloutofband(struct socket *, struct tcpiphdr *, struct mbuf *);
@@ -67,7 +69,9 @@ int	tcprexmtthresh = 3;
 int	tcppredack;	/* XXX debugging: times hdr predict ok for acks */
 int	tcppreddat;	/* XXX # times header prediction ok for data packets */
 int	tcppcbcachemiss;
+#ifdef TCPDEBUG
 struct	tcpiphdr tcp_saveti;
+#endif
 struct	inpcb *tcp_last_inpcb = &tcb;
 
 
@@ -219,10 +223,12 @@ tcp_input(m, iphlen)
 	register int tiflags;
 	struct socket *so = 0;
 	int todrop, acked, ourfinisacked, needoutput = 0;
-	short ostate = 0;
 	struct in_addr laddr;
 	int dropsocket = 0;
 	int iss = 0;
+#ifdef TCPDEBUG
+	short ostate = 0;
+#endif
 
 	tcpstat.tcps_rcvtotal++;
 	/*
@@ -326,10 +332,12 @@ findpcb:
 		goto drop;
 	so = inp->inp_socket;
 	if (so->so_options & (SO_DEBUG|SO_ACCEPTCONN)) {
+#ifdef TCPDEBUG
 		if (so->so_options & SO_DEBUG) {
 			ostate = tp->t_state;
 			tcp_saveti = *ti;
 		}
+#endif
 		if (so->so_options & SO_ACCEPTCONN) {
 			so = sonewconn(so, 0);
 			if (so == 0)
@@ -448,7 +456,17 @@ findpcb:
 			m->m_len -= sizeof(struct tcpiphdr);
 			sbappend(&so->so_rcv, m);
 			sorwakeup(so);
-			tp->t_flags |= TF_DELACK;
+			/*
+			 * If this is a small packet, then ACK now - with Nagel
+			 *	congestion avoidance sender won't send more until
+			 *	he gets an ACK.
+			 */
+			if ((unsigned)ti->ti_len < tp->t_maxseg) {
+				tp->t_flags |= TF_ACKNOW;
+				tcp_output(tp);
+			} else {
+				tp->t_flags |= TF_DELACK;
+			}
 			return;
 		}
 	}
@@ -1149,8 +1167,18 @@ dodata:							/* XXX */
 			break;
 		}
 	}
+#ifdef TCPDEBUG
 	if (so->so_options & SO_DEBUG)
 		tcp_trace(TA_INPUT, ostate, tp, &tcp_saveti, 0);
+#endif
+
+	/*
+	 * If this is a small packet, then ACK now - with Nagel
+	 *	congestion avoidance sender won't send more until
+	 *	he gets an ACK.
+	 */
+	if (ti->ti_len && ((unsigned)ti->ti_len < tp->t_maxseg))
+		tp->t_flags |= TF_ACKNOW;
 
 	/*
 	 * Return any desired output.
@@ -1202,8 +1230,10 @@ drop:
 	/*
 	 * Drop space held by incoming segment and return.
 	 */
+#ifdef TCPDEBUG
 	if (tp && (tp->t_inpcb->inp_socket->so_options & SO_DEBUG))
 		tcp_trace(TA_DROP, ostate, tp, &tcp_saveti, 0);
+#endif
 	m_freem(m);
 	/* destroy temporarily created socket */
 	if (dropsocket)
@@ -1470,20 +1500,22 @@ tcp_mss(tp, offer)
 			bufsize = so->so_snd.sb_hiwat;
 		if (bufsize < mss)
 			mss = bufsize;
-		else {
+		else
 			bufsize = min(bufsize, SB_MAX) / mss * mss;
-			(void) sbreserve(&so->so_snd, bufsize);
-		}
+
+		(void) sbreserve(&so->so_snd, bufsize);
 		tp->t_maxseg = mss;
 
 #ifdef RTV_RPIPE
 		if ((bufsize = rt->rt_rmx.rmx_recvpipe) == 0)
 #endif
 			bufsize = so->so_rcv.sb_hiwat;
-		if (bufsize > mss) {
+		if (bufsize < mss)
+			bufsize = mss;
+		else
 			bufsize = min(bufsize, SB_MAX) / mss * mss;
-			(void) sbreserve(&so->so_rcv, bufsize);
-		}
+
+		(void) sbreserve(&so->so_rcv, bufsize);
 	}
 	tp->snd_cwnd = mss;