suppress silly-windowness

[unix-history] / usr / src / sys / netinet / tcp_output.c

diff --git a/usr/src/sys/netinet/tcp_output.c b/usr/src/sys/netinet/tcp_output.c
index 40e5a0d..f75fda2 100644 (file)
--- a/usr/src/sys/netinet/tcp_output.c
+++ b/usr/src/sys/netinet/tcp_output.c
@@ -1,4 +1,4 @@
-/*     tcp_output.c    4.34    82/03/15        */
+/*     tcp_output.c    4.35    82/03/20        */

 
 #include "../h/param.h"
 #include "../h/systm.h"
 
 #include "../h/param.h"
 #include "../h/systm.h"


@@ -52,7 +52,7 @@ tcp_output(tp)
 COUNT(TCP_OUTPUT);
 
        /*
 COUNT(TCP_OUTPUT);
 
        /*

-        * Determine length of data that can be transmitted,
+        * Determine length of data that should be transmitted,

         * and flags that will be used.
         * If there is some data or critical controls (SYN, RST)
         * to send, then transmit; otherwise, investigate further.
         * and flags that will be used.
         * If there is some data or critical controls (SYN, RST)
         * to send, then transmit; otherwise, investigate further.


@@ -63,12 +63,29 @@ COUNT(TCP_OUTPUT);
                return (0);                     /* past FIN */
        if (len > tp->t_maxseg)
                len = tp->t_maxseg;
                return (0);                     /* past FIN */
        if (len > tp->t_maxseg)
                len = tp->t_maxseg;

+

        flags = tcp_outflags[tp->t_state];
        if (tp->snd_nxt + len < tp->snd_una + so->so_snd.sb_cc)
                flags &= ~TH_FIN;
        flags = tcp_outflags[tp->t_state];
        if (tp->snd_nxt + len < tp->snd_una + so->so_snd.sb_cc)
                flags &= ~TH_FIN;

-       if (len || (flags & (TH_SYN|TH_RST|TH_FIN)))
+       if (flags & (TH_SYN|TH_RST|TH_FIN))
+               goto send;
+       if (SEQ_GT(tp->snd_up, tp->snd_una))

                goto send;
 
                goto send;
 

+       /*
+        * Sender silly window avoidance.  If can send all data,
+        * a maximum segment, at least 1/4 of window do it,
+        * or are forced, do it; otherwise don't bother.
+        */
+       if (len) {
+               if (len == tp->t_maxseg || off+len >= so->so_snd.sb_cc)
+                       goto send;
+               if (len * 4 >= tp->snd_wnd)             /* a lot */
+                       goto send;
+               if (tp->t_force)
+                       goto send;
+       }
+

        /*
         * Send if we owe peer an ACK.
         */
        /*
         * Send if we owe peer an ACK.
         */


@@ -203,8 +220,14 @@ printf("tp %x send OOBDATA seq %x data %x\n", tp->t_oobseq, tp->t_oobc);
 noopt:
        ti->ti_flags = flags;
        win = sbspace(&so->so_rcv);
 noopt:
        ti->ti_flags = flags;
        win = sbspace(&so->so_rcv);

+       if (win < so->so_rcv.sb_hiwat / 4)      /* avoid silly window */
+               win = 0;

        if (win > 0)
        if (win > 0)

+#if vax

                ti->ti_win = htons((u_short)win);
                ti->ti_win = htons((u_short)win);

+#else
+               ti->ti_win = win;
+#endif

        if (SEQ_GT(tp->snd_up, tp->snd_nxt)) {
                ti->ti_urp = tp->snd_up - tp->snd_nxt;
 #if vax
        if (SEQ_GT(tp->snd_up, tp->snd_nxt)) {
                ti->ti_urp = tp->snd_up - tp->snd_nxt;
 #if vax