Update last_known_tag to FOREVER when an input connection closes

include/reactor-uc/network_channel.h

@@ -14,6 +14,7 @@ typedef struct NetworkChannel NetworkChannel;
 
 struct NetworkChannel {
   size_t dest_channel_id; // So that we can "address" one of several NetworkChannel's at the other end.
+
   lf_ret_t (*open_connection)(NetworkChannel *self);
 
   /** Try to connect to corresponding NetworkChannel on another federate.

src/federated.c

@@ -61,6 +61,8 @@ void FederatedOutputConnection_cleanup(Trigger *trigger) {
            tagged_msg->tag.microstep);
   lf_ret_t ret = channel->send_blocking(channel, &msg);
 
+  // TODO: If send_blocking returns LF_CONNECTION_CLOSEd then we should update some state
+  // and not try again.
   if (ret != LF_OK) {
     LF_ERR(FED, "FedOutConn %p failed to send message", trigger);
   }

src/platform/posix/tcp_ip_channel.c

@@ -408,7 +408,11 @@ static void *TcpIpChannel_receive_thread(void *untyped_self) {
       self->receive_callback(self->federated_connection, &self->output);
       break;
     case LF_CONNECTION_CLOSED:
-      LF_INFO(NET, "Connection closed");
+      LF_INFO(NET, "Connection closed. Setting last known tag to FOREVER for all input ports");
+      for (int i = 0; i < self->federated_connection->inputs_size; i++) {
+        FederatedInputConnection *input = self->federated_connection->inputs[i];
+        input->last_known_tag = FOREVER_TAG;
+      }
       self->terminate = true;
       break;
     default: