From: David Goulet <dgoulet@efficios.com>
Date: Tue, 25 Mar 2014 15:34:47 +0000 (-0400)
Subject: Fix: don't ask data pending if session was not started
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=2e4e8c2d5207b86e35092e7b6ee3b0d1463138b1;p=lttng-tools.git

Fix: don't ask data pending if session was not started

Fixes #770

Signed-off-by: David Goulet <dgoulet@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index 2a61eee06..339a7659e 100644
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -2301,6 +2301,21 @@ int cmd_data_pending(struct ltt_session *session)
 	if (session->enabled) {
 		ret = LTTNG_ERR_SESSION_STARTED;
 		goto error;
+	} else {
+		/*
+		 * If stopped, just make sure we've started before else the above call
+		 * will always send that there is data pending.
+		 *
+		 * The consumer assumes that when the data pending command is received,
+		 * the trace has been started before or else no output data is written
+		 * by the streams which is a condition for data pending. So, this is
+		 * *VERY* important that we don't ask the consumer before a start
+		 * trace.
+		 */
+		if (!session->started) {
+			ret = 0;
+			goto error;
+		}
 	}
 
 	if (ksess && ksess->consumer) {