From 1a2416565951eff19530564c552931cc71866e8c Mon Sep 17 00:00:00 2001
From: David Goulet <dgoulet@efficios.com>
Date: Mon, 24 Mar 2014 14:23:00 -0400
Subject: [PATCH 1/1] Fix: allow empty URL for live session creation

This is actually very important so -C/-D can be used with lttng create
--live command and also the load command can set the control and data
URL independently.

This also adds a small test to make sure -C/-D works in live mode.

Fixes #769

Signed-off-by: David Goulet <dgoulet@efficios.com>
---
 src/bin/lttng/commands/create.c            | 24 +++++++++++++---------
 src/lib/lttng-ctl/lttng-ctl.c              | 22 ++++++++++++--------
 tests/regression/tools/live/test_lttng_ust | 15 ++++++++++++--
 3 files changed, 40 insertions(+), 21 deletions(-)

diff --git a/src/bin/lttng/commands/create.c b/src/bin/lttng/commands/create.c
index a5f92f14a..4a47d6714 100644
--- a/src/bin/lttng/commands/create.c
+++ b/src/bin/lttng/commands/create.c
@@ -291,6 +291,12 @@ static int create_session(void)
 		}
 	}
 
+	if ((!opt_ctrl_url && opt_data_url) || (opt_ctrl_url && !opt_data_url)) {
+		ERR("You need both control and data URL.");
+		ret = CMD_ERROR;
+		goto error;
+	}
+
 	if (opt_output_path != NULL) {
 		traces_path = utils_expand_path(opt_output_path);
 		if (traces_path == NULL) {
@@ -311,6 +317,12 @@ static int create_session(void)
 	} else if (opt_url) { /* Handling URL (-U opt) */
 		url = opt_url;
 		print_str_url = url;
+	} else if (opt_data_url && opt_ctrl_url) {
+		/*
+		 * With both control and data, we'll be setting the consumer URL after
+		 * session creation thus use no URL.
+		 */
+		url = NULL;
 	} else if (!opt_no_output) {
 		/* Auto output path */
 		alloc_path = utils_get_home_dir();
@@ -332,22 +344,14 @@ static int create_session(void)
 		}
 
 		url = alloc_url;
-		if (!opt_data_url && !opt_ctrl_url) {
-			print_str_url = alloc_url + strlen("file://");
-		}
+		print_str_url = alloc_url + strlen("file://");
 	} else {
 		/* No output means --no-output or --snapshot mode. */
 		url = NULL;
 	}
 
-	if ((!opt_ctrl_url && opt_data_url) || (opt_ctrl_url && !opt_data_url)) {
-		ERR("You need both control and data URL.");
-		ret = CMD_ERROR;
-		goto error;
-	}
-
+	/* Use default live URL if NO url is/are found. */
 	if ((opt_live_timer && !opt_url) && (opt_live_timer && !opt_data_url)) {
-		/* Use default live URL if none is found. */
 		ret = asprintf(&alloc_url, "net://127.0.0.1");
 		if (ret < 0) {
 			PERROR("asprintf default live URL");
diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index 8e2593db1..100e587d9 100644
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -1572,16 +1572,20 @@ int lttng_create_session_live(const char *name, const char *url,
 	lsm.cmd_type = LTTNG_CREATE_SESSION_LIVE;
 	lttng_ctl_copy_string(lsm.session.name, name, sizeof(lsm.session.name));
 
-	size = uri_parse_str_urls(url, NULL, &uris);
-	if (size <= 0) {
-		ret = -LTTNG_ERR_INVALID;
-		goto end;
-	}
+	if (url) {
+		size = uri_parse_str_urls(url, NULL, &uris);
+		if (size <= 0) {
+			ret = -LTTNG_ERR_INVALID;
+			goto end;
+		}
 
-	/* file:// is not accepted for live session. */
-	if (uris[0].dtype == LTTNG_DST_PATH) {
-		ret = -LTTNG_ERR_INVALID;
-		goto end;
+		/* file:// is not accepted for live session. */
+		if (uris[0].dtype == LTTNG_DST_PATH) {
+			ret = -LTTNG_ERR_INVALID;
+			goto end;
+		}
+	} else {
+		size = 0;
 	}
 
 	lsm.u.session_live.nb_uri = size;
diff --git a/tests/regression/tools/live/test_lttng_ust b/tests/regression/tools/live/test_lttng_ust
index 70af04314..db63b4b87 100755
--- a/tests/regression/tools/live/test_lttng_ust
+++ b/tests/regression/tools/live/test_lttng_ust
@@ -38,7 +38,7 @@ TRACE_PATH=$(mktemp -d)
 
 DIR=$(readlink -f $TESTDIR)
 
-NUM_TESTS=10
+NUM_TESTS=11
 
 source $TESTDIR/utils/utils.sh
 
@@ -47,6 +47,14 @@ plan_tests $NUM_TESTS
 
 print_test_banner "$TEST_DESC"
 
+function test_custom_url()
+{
+	# Create session with custom URL
+	$TESTDIR/../src/bin/lttng/$LTTNG_BIN create $SESSION_NAME --live $DELAY_USEC \
+		-C tcp://localhost:1819 -D tcp://localhost:9187 >/dev/null 2>&1
+	ok $? "Create session in live mode with delay $DELAY_USEC and custom URLs"
+}
+
 function setup_live_tracing()
 {
 	# Create session with default path
@@ -80,6 +88,9 @@ clean_live_tracing
 
 trace_matches $EVENT_NAME $NR_ITER $TRACE_PATH
 rm -rf $TRACE_PATH
-
 stop_lttng_relayd
+
+test_custom_url
+pkill $RELAYD_BIN
+
 stop_lttng_sessiond
-- 
2.34.1