Fixes #1606: Prevent connection activation if the listener or connect…

…or is closed

src/adaptors/tcp/tcp_adaptor.c

@@ -279,14 +279,6 @@ static void on_activate(void *context)
 
     qd_log(LOG_TCP_ADAPTOR, QD_LOG_DEBUG, "[C%" PRIu64 "] on_activate", conn->conn_id);
     while (qdr_connection_process(conn->qdr_conn)) {}
-    if (conn->is_egress_dispatcher_conn && conn->connector_closed) {
-        detach_links(conn);
-        qdr_connection_set_context(conn->qdr_conn, 0);
-        qdr_connection_closed(conn->qdr_conn);
-        qd_connection_counter_dec(QD_PROTOCOL_TCP);
-        conn->qdr_conn = 0;
-        free_qdr_tcp_connection(conn);
-    }
 }
 
 /**
@@ -1859,40 +1851,50 @@ qd_tcp_connector_t *qd_dispatch_configure_tcp_connector_legacy(qd_dispatch_t *qd
     return c;
 }
 
-void qd_dispatch_delete_tcp_connector_legacy(qd_dispatch_t *qd, qd_tcp_connector_t *ct)
+void qd_dispatch_delete_tcp_connector_legacy(qd_dispatch_t *qd, qd_tcp_connector_t *connector)
 {
-    if (ct) {
+    if (connector) {
         qd_log(LOG_TCP_ADAPTOR, QD_LOG_INFO, "Deleted TcpConnector for %s, %s:%s",
-               ct->config->adaptor_config->address, ct->config->adaptor_config->host, ct->config->adaptor_config->port);
+                connector->config->adaptor_config->address, connector->config->adaptor_config->host, connector->config->adaptor_config->port);
 
-        // need to close the pseudo-connection used for dispatching
-        // deliveries out to live connections:
-        handle_disconnected((qdr_tcp_connection_t*) ct->dispatcher_conn);
-        ct->dispatcher_conn = 0;
-        DEQ_REMOVE(tcp_adaptor->connectors, ct);
+        DEQ_REMOVE(tcp_adaptor->connectors, connector);
 
         //
         // Initiate termination of existing connections
         //
+        qd_timer_t *temp_timer = 0;
         if (qd->terminate_tcp_conns) {
             // Note: PN_RAW_CONNECTION_CONNECTED event or PN_RAW_CONNECTION_DISCONNECTED event
             // could come upon any of the connections. We need to hold the connector->lock
             // to prevent any modification of the connections list while it is being traversed.
-            sys_mutex_lock(&ct->lock);
-            SET_ATOMIC_FLAG(&ct->closing);
+            sys_mutex_lock(&connector->lock);
+            qdr_tcp_connection_t* dispatcher_conn = connector->dispatcher_conn;
+            qd_timer_cancel(dispatcher_conn->activate_timer);
+            temp_timer = dispatcher_conn->activate_timer;
+            dispatcher_conn->activate_timer = 0;
+            SET_ATOMIC_FLAG(&connector->closing);
             //
             // Only the head connection is woken when holding the lock.
             // This is an optimization. The next connection in the list is woken up in the handler of the PN_RAW_DISCONNECTED
             // event of this connection (See close_connection_XSIDE_IO() to see where the next connection in the list is woken up).
             // That way, we don't have to wake all the connections when holding the lock.
             //
-            qdr_tcp_connection_t *conn = DEQ_HEAD(ct->connections);
-            if (conn)
+            qdr_tcp_connection_t *conn = DEQ_HEAD(connector->connections);
+            if (conn && conn->pn_raw_conn)
                 pn_raw_connection_wake(conn->pn_raw_conn);
-            sys_mutex_unlock(&ct->lock);
+            sys_mutex_unlock(&connector->lock);
         }
 
-        qd_tcp_connector_decref(ct);
+        if (temp_timer) {
+            qd_timer_free(temp_timer);
+        }
+
+        // need to close the pseudo-connection used for dispatching
+        // deliveries out to live connections:
+        handle_disconnected((qdr_tcp_connection_t*) connector->dispatcher_conn);
+        connector->dispatcher_conn = 0;
+
+        qd_tcp_connector_decref(connector);
     }
 }
 
@@ -2428,7 +2430,18 @@ static void qdr_tcp_activate_CT(void *notused, qdr_connection_t *c)
             // fake wakeup by using a timer.
             qd_log(LOG_TCP_ADAPTOR, QD_LOG_DEBUG,
                    "[C%" PRIu64 "] qdr_tcp_activate_CT: schedule activate_timer", conn->conn_id);
-            qd_timer_schedule(conn->activate_timer, 0);
+
+            //
+            // https://github.com/skupperproject/skupper-router/issues/1606
+            // Do not schedule a zero length activate_timer if the connector is closing.
+            //
+            assert(conn->is_egress_dispatcher_conn);
+            qd_tcp_connector_t *connector = conn->connector;
+            sys_mutex_lock(&connector->lock);
+            if (!IS_ATOMIC_FLAG_SET(&connector->closing) && conn->activate_timer) {
+                qd_timer_schedule(conn->activate_timer, 0);
+            }
+            sys_mutex_unlock(&connector->lock);
         } else {
             UNLOCK(&conn->activation_lock);
             qd_log(LOG_TCP_ADAPTOR, QD_LOG_DEBUG, "[C%" PRIu64 "] qdr_tcp_activate_CT: Cannot activate",