APP may not have set NAK

diff --git a/src/lib/io/worker.c b/src/lib/io/worker.c
index 296278e0b5276122e49eab2699c4eca4b0b5e465..f30eaa16a66edff15295d3bfb14dc8c9faedb02a 100644 (file)
--- a/src/lib/io/worker.c
+++ b/src/lib/io/worker.c
@@ -366,8 +366,12 @@ static void fr_worker_nak(fr_worker_t *worker, fr_channel_data_t *cd, fr_time_t
        /*
         *      Encode a NAK
         */
-       size = listen->app_io->nak(listen->app_io_instance, cd->m.data,
-                                  cd->m.data_size, reply->m.data, reply->m.rb_size);
+       if (listen->app_io->nak) {
+               size = listen->app_io->nak(listen->app_io_instance, cd->m.data,
+                                          cd->m.data_size, reply->m.data, reply->m.rb_size);
+       } else {
+               size = 1;       /* rely on them to figure it the heck out */
+       }
 
        (void) fr_message_alloc(ms, &reply->m, size);