Fix: src.ctf.lttng-live: omitting stream end on stream hang up

[babeltrace.git] / src / plugins / ctf / lttng-live / lttng-live.c

diff --git a/src/plugins/ctf/lttng-live/lttng-live.c b/src/plugins/ctf/lttng-live/lttng-live.c
index 40d76b9d2ad5d6f08e8aaf47480df20d56827585..7760daf650099e25f89d9929396e859bf09531dc 100644 (file)
--- a/src/plugins/ctf/lttng-live/lttng-live.c
+++ b/src/plugins/ctf/lttng-live/lttng-live.c
@@ -793,6 +793,34 @@ end:
        return ret;
 }
 
+static
+enum lttng_live_iterator_status lttng_live_iterator_close_stream(
+               struct lttng_live_msg_iter *lttng_live_msg_iter,
+               struct lttng_live_stream_iterator *stream_iter,
+               bt_message **curr_msg)
+{
+       enum lttng_live_iterator_status live_status =
+               LTTNG_LIVE_ITERATOR_STATUS_OK;
+       /*
+        * The viewer has hung up on us so we are closing the stream. The
+        * `bt_msg_iter` should simply realize that it needs to close the
+        * stream properly by emitting the necessary stream end message.
+        */
+       enum bt_msg_iter_status status =
+               bt_msg_iter_get_next_message(stream_iter->msg_iter,
+                       lttng_live_msg_iter->self_msg_iter, curr_msg);
+
+       if (status == BT_MSG_ITER_STATUS_ERROR) {
+               live_status = LTTNG_LIVE_ITERATOR_STATUS_ERROR;
+               goto end;
+       }
+
+       BT_ASSERT(status == BT_MSG_ITER_STATUS_OK);
+
+end:
+       return live_status;
+}
+
 /*
  * helper function:
  *            handle_no_data_streams()
@@ -851,6 +879,17 @@ enum lttng_live_iterator_status lttng_live_iterator_next_on_stream(
        bt_self_component *self_comp = lttng_live_msg_iter->self_comp;
        enum lttng_live_iterator_status live_status;
 
+       if (stream_iter->has_stream_hung_up) {
+               /*
+                * The stream has hung up and the stream was properly closed
+                * during the last call to the current function. Return _END
+                * status now so that this stream iterator is removed for the
+                * stream iterator list.
+                */
+               live_status = LTTNG_LIVE_ITERATOR_STATUS_END;
+               goto end;
+       }
+
 retry:
        print_stream_state(stream_iter);
        live_status = lttng_live_iterator_handle_new_streams_and_metadata(
@@ -860,7 +899,16 @@ retry:
        }
        live_status = lttng_live_iterator_next_handle_one_no_data_stream(
                        lttng_live_msg_iter, stream_iter);
+
        if (live_status != LTTNG_LIVE_ITERATOR_STATUS_OK) {
+               if (live_status == LTTNG_LIVE_ITERATOR_STATUS_END) {
+                       /*
+                        * We overwrite `live_status` since `curr_msg` is
+                        * likely set to a valid message in this function.
+                        */
+                       live_status = lttng_live_iterator_close_stream(
+                               lttng_live_msg_iter, stream_iter, curr_msg);
+               }
                goto end;
        }
        live_status = lttng_live_iterator_next_handle_one_quiescent_stream(