Update test program to set a better default MTU.

[utcp] / utcp.c

diff --git a/utcp.c b/utcp.c
index 4c3cbdb36fc46bb43c36c7fdd5e4cc6cbac3c964..5d630694df96100f57e780f855a32cc63f7674bc 100644 (file)
--- a/utcp.c
+++ b/utcp.c
@@ -415,13 +415,13 @@ static void update_rtt(struct utcp_connection *c, uint32_t rtt) {
        if(!utcp->srtt) {
                utcp->srtt = rtt;
                utcp->rttvar = rtt / 2;
-               utcp->rto = rtt + max(2 * rtt, CLOCK_GRANULARITY);
        } else {
                utcp->rttvar = (utcp->rttvar * 3 + absdiff(utcp->srtt, rtt)) / 4;
                utcp->srtt = (utcp->srtt * 7 + rtt) / 8;
-               utcp->rto = utcp->srtt + max(utcp->rttvar, CLOCK_GRANULARITY);
        }
 
+       utcp->rto = utcp->srtt + max(4 * utcp->rttvar, CLOCK_GRANULARITY);
+
        if(utcp->rto > MAX_RTO) {
                utcp->rto = MAX_RTO;
        }
@@ -629,6 +629,8 @@ ssize_t utcp_send(struct utcp_connection *c, const void *data, size_t len) {
 
        if(is_reliable(c) || (c->state != SYN_SENT && c->state != SYN_RECEIVED)) {
                len = buffer_put(&c->sndbuf, data, len);
+       } else {
+               return 0;
        }
 
        if(len <= 0) {
@@ -1055,6 +1057,7 @@ ssize_t utcp_recv(struct utcp *utcp, const void *data, size_t len) {
                                c->flags = UTCP_TCP;
                        }
 
+synack:
                        // Return SYN+ACK, go to SYN_RECEIVED state
                        c->snd.wnd = hdr.wnd;
                        c->rcv.irs = hdr.seq;
@@ -1313,8 +1316,10 @@ ssize_t utcp_recv(struct utcp *utcp, const void *data, size_t len) {
 
                assert(data_acked >= 0);
 
+#ifndef NDEBUG
                int32_t bufused = seqdiff(c->snd.last, c->snd.una);
                assert(data_acked <= bufused);
+#endif
 
                if(data_acked) {
                        buffer_get(&c->sndbuf, NULL, data_acked);
@@ -1346,7 +1351,7 @@ ssize_t utcp_recv(struct utcp *utcp, const void *data, size_t len) {
                case CLOSING:
                        if(c->snd.una == c->snd.last) {
                                gettimeofday(&c->conn_timeout, NULL);
-                               c->conn_timeout.tv_sec += 60;
+                               c->conn_timeout.tv_sec += utcp->timeout;
                                set_state(c, TIME_WAIT);
                        }
 
@@ -1410,6 +1415,9 @@ skip_ack:
                        break;
 
                case SYN_RECEIVED:
+                       // This is a retransmit of a SYN, send back the SYNACK.
+                       goto synack;
+
                case ESTABLISHED:
                case FIN_WAIT_1:
                case FIN_WAIT_2:
@@ -1505,7 +1513,7 @@ skip_ack:
 
                case FIN_WAIT_2:
                        gettimeofday(&c->conn_timeout, NULL);
-                       c->conn_timeout.tv_sec += 60;
+                       c->conn_timeout.tv_sec += utcp->timeout;
                        set_state(c, TIME_WAIT);
                        break;