Fix: relayd: per-pid live: no new metadata vs close

[lttng-tools.git] / src / bin / lttng-relayd / live.c

diff --git a/src/bin/lttng-relayd/live.c b/src/bin/lttng-relayd/live.c
index f00f07db1b8e63fc280c5a868379da2a47a68ade..1b25671d5f76a82ad83a33ceceb3691e8794457c 100644 (file)
--- a/src/bin/lttng-relayd/live.c
+++ b/src/bin/lttng-relayd/live.c
@@ -1724,7 +1724,23 @@ int viewer_get_metadata(struct relay_connection *conn)
 
        len = vstream->stream->metadata_received - vstream->metadata_sent;
        if (len == 0) {
+               /*
+                * The live viewers expect to receive a NO_NEW_METADATA
+                * status before a stream disappears, otherwise they abort the
+                * entire live connection when receiving an error status.
+                */
                reply.status = htobe32(LTTNG_VIEWER_NO_NEW_METADATA);
+               /*
+                * The live viewer considers a closed 0 byte metadata stream as
+                * an error.
+                */
+               if (vstream->metadata_sent > 0) {
+                       vstream->stream->no_new_metadata_notified = true;
+                       if (vstream->stream->closed) {
+                               /* Release ownership for the viewer metadata stream. */
+                               viewer_stream_put(vstream);
+                       }
+               }
                goto send_reply;
        }
 
@@ -1772,12 +1788,6 @@ int viewer_get_metadata(struct relay_connection *conn)
                goto error;
        }
        vstream->metadata_sent += read_len;
-       if (vstream->metadata_sent == vstream->stream->metadata_received
-                       && vstream->stream->closed) {
-               /* Release ownership for the viewer metadata stream. */
-               viewer_stream_put(vstream);
-       }
-
        reply.status = htobe32(LTTNG_VIEWER_METADATA_OK);
 
        goto send_reply;