[lttng-dev] [PATCH lttng-tools 1/2] Fix relayd: initialize beacon to -1ULL

[Mathieu Desnoyers]

The relayd stream beacon_ts_end field is expected to have the value
-1ULL when unset (no beacon has been received since last index).

However, the initial state is wrong. It is left at the value 0, which
indicates that a live beacon has indeed been received (which is untrue),
which in turn causes a live beacon with ctf_stream_id of -1ULL to be
sent to babeltrace, which does not expect it, and fails.

This issue can be triggered with the following scenario:

1) create live session
2) setup UST per-uid buffers tracing
3) start tracing, without any active traced application
4) hook with babeltrace live client to view the trace
5) run a traced application

Step 5) will cause the babeltrace live client to receive a stream_id of
-1ULL, and error out.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
---
 src/bin/lttng-relayd/stream.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/bin/lttng-relayd/stream.c b/src/bin/lttng-relayd/stream.c
index 80c8aa0c..1218c2f4 100644
--- a/src/bin/lttng-relayd/stream.c
+++ b/src/bin/lttng-relayd/stream.c
@@ -98,6 +98,7 @@ struct relay_stream *stream_create(struct ctf_trace *trace,
 	stream->tracefile_count = tracefile_count;
 	stream->path_name = path_name;
 	stream->channel_name = channel_name;
+	stream->beacon_ts_end = -1ULL;
 	lttng_ht_node_init_u64(&stream->node, stream->stream_handle);
 	pthread_mutex_init(&stream->lock, NULL);
 	pthread_mutex_init(&stream->reflock, NULL);
-- 
2.17.1