From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Thu, 5 Nov 2015 21:19:38 +0000 (-0500)
Subject: Fix: loading of live session within userspace domains
X-Git-Tag: v2.9.0-rc1~244
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=95681498599cbd3bc1aa6dfa725a668ab272170b;p=lttng-tools.git

Fix: loading of live session within userspace domains

The output of a session is session-specific and not bound to
a domain. The "lttng_set_consumer_url" already acts on a
session-wide basis.

Fixes #973

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/include/lttng/domain.h b/include/lttng/domain.h
index bff134a84..1e40b392a 100644
--- a/include/lttng/domain.h
+++ b/include/lttng/domain.h
@@ -28,6 +28,7 @@ extern "C" {
  * Domain types: the different possible tracers.
  */
 enum lttng_domain_type {
+	LTTNG_DOMAIN_NONE                     = 0,	/* No associated domain. */
 	LTTNG_DOMAIN_KERNEL                   = 1,	/* Linux Kernel tracer. */
 	LTTNG_DOMAIN_UST                      = 2,	/* Global Userspace tracer. */
 	LTTNG_DOMAIN_JUL                      = 3,	/* Java Util Logging. */
diff --git a/include/lttng/handle.h b/include/lttng/handle.h
index a313e7963..c5958b402 100644
--- a/include/lttng/handle.h
+++ b/include/lttng/handle.h
@@ -43,7 +43,11 @@ struct lttng_handle {
  * This handle contains the session name and domain on which the command will
  * be executed. A domain is basically a tracer like the kernel or user space.
  *
- * Return an newly allocated handle that should be freed using
+ * A NULL domain indicates that the handle is not bound to a specific domain.
+ * This is mostly used for actions that apply on a session and not on a domain
+ * (e.g lttng_set_consumer_url).
+ *
+ * Return a newly allocated handle that should be freed using
  * lttng_destroy_handle. On error, NULL is returned.
  */
 extern struct lttng_handle *lttng_create_handle(const char *session_name,
diff --git a/src/bin/lttng/commands/create.c b/src/bin/lttng/commands/create.c
index 525464aa8..3379a3b27 100644
--- a/src/bin/lttng/commands/create.c
+++ b/src/bin/lttng/commands/create.c
@@ -141,18 +141,15 @@ static int set_consumer_url(const char *session_name, const char *ctrl_url,
 {
 	int ret;
 	struct lttng_handle *handle;
-	struct lttng_domain dom;
 
 	assert(session_name);
 
 	/*
-	 * Set handle with the session name and the domain set to 0. This means to
-	 * the session daemon that the next action applies on the tracing session
-	 * rather then the domain specific session.
+	 * Set handle with the session_name, but no domain. This implies that
+	 * the actions taken with this handle apply on the tracing session
+	 * rather then the domain-specific session.
 	 */
-	memset(&dom, 0, sizeof(dom));
-
-	handle = lttng_create_handle(session_name, &dom);
+	handle = lttng_create_handle(session_name, NULL);
 	if (handle == NULL) {
 		ret = CMD_FATAL;
 		goto error;
diff --git a/src/common/config/session-config.c b/src/common/config/session-config.c
index eea6c0a81..48094c59a 100644
--- a/src/common/config/session-config.c
+++ b/src/common/config/session-config.c
@@ -1151,17 +1151,16 @@ end:
 }
 
 static
-int create_session_net_output(const char *name, struct lttng_domain *domain,
-	const char *control_uri, const char *data_uri)
+int create_session_net_output(const char *name, const char *control_uri,
+		const char *data_uri)
 {
 	int ret;
 	struct lttng_handle *handle;
 	const char *uri = NULL;
 
 	assert(name);
-	assert(domain);
 
-	handle = lttng_create_handle(name, domain);
+	handle = lttng_create_handle(name, NULL);
 	if (!handle) {
 		ret = -LTTNG_ERR_NOMEM;
 		goto end;
@@ -1343,11 +1342,6 @@ int create_session(const char *name,
 	}
 
 	if (output.control_uri || output.data_uri) {
-		int i;
-		struct lttng_domain *domain;
-		struct lttng_domain *domains[] =
-			{ kernel_domain, ust_domain, jul_domain, log4j_domain };
-
 		/* network destination */
 		if (live_timer_interval && live_timer_interval != UINT64_MAX) {
 			/*
@@ -1363,18 +1357,12 @@ int create_session(const char *name,
 			goto end;
 		}
 
-		for (i = 0; i < (sizeof(domains) / sizeof(domains[0])); i++) {
-			domain = domains[i];
-			if (!domain) {
-				continue;
-			}
-
-			ret = create_session_net_output(name, domain, output.control_uri,
-					output.data_uri);
-			if (ret) {
-				goto end;
-			}
+		ret = create_session_net_output(name, output.control_uri,
+				output.data_uri);
+		if (ret) {
+			goto end;
 		}
+
 	} else {
 		/* either local output or no output */
 		ret = lttng_create_session(name, output.path);
diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index 4df1bdf3f..d0deade2e 100644
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -519,10 +519,6 @@ struct lttng_handle *lttng_create_handle(const char *session_name,
 {
 	struct lttng_handle *handle = NULL;
 
-	if (domain == NULL) {
-		goto end;
-	}
-
 	handle = zmalloc(sizeof(struct lttng_handle));
 	if (handle == NULL) {
 		PERROR("malloc handle");
@@ -533,8 +529,10 @@ struct lttng_handle *lttng_create_handle(const char *session_name,
 	lttng_ctl_copy_string(handle->session_name, session_name,
 			sizeof(handle->session_name));
 
-	/* Copy lttng domain */
-	lttng_ctl_copy_lttng_domain(&handle->domain, domain);
+	/* Copy lttng domain or leave initialized to 0. */
+	if (domain) {
+		lttng_ctl_copy_lttng_domain(&handle->domain, domain);
+	}
 
 end:
 	return handle;