From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Mon, 22 Jul 2024 19:16:27 +0000 (+0000)
Subject: Clean-up: sessiond: automatic memory management of ltt_ust_event
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=5e3dc005e20046f3380aa464f83a78a3e7296c05;p=lttng-tools.git

Clean-up: sessiond: automatic memory management of ltt_ust_event

Simplify trace_ust_create_event by wrapping the created ltt_ust_event
in a unique_ptr until it is returned (on success).

Change-Id: I1b14df589f30d4cd19c9712b70f6c5656335123b
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/trace-ust.cpp b/src/bin/lttng-sessiond/trace-ust.cpp
index 4d15bd758..8937dd205 100644
--- a/src/bin/lttng-sessiond/trace-ust.cpp
+++ b/src/bin/lttng-sessiond/trace-ust.cpp
@@ -449,8 +449,8 @@ enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 					     bool internal_event,
 					     struct ltt_ust_event **ust_event)
 {
-	struct ltt_ust_event *local_ust_event;
 	enum lttng_error_code ret = LTTNG_OK;
+	std::unique_ptr<ltt_ust_event> local_ust_event;
 
 	LTTNG_ASSERT(ev);
 
@@ -459,9 +459,10 @@ enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 		goto error;
 	}
 
-	local_ust_event = zmalloc<ltt_ust_event>();
-	if (local_ust_event == nullptr) {
-		PERROR("ust event zmalloc");
+	try {
+		local_ust_event = lttng::make_unique<ltt_ust_event>();
+	} catch (const std::bad_alloc &ex) {
+		ERR_FMT("Failed to allocate ltt_ust_event");
 		ret = LTTNG_ERR_NOMEM;
 		goto error;
 	}
@@ -484,7 +485,7 @@ enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 	default:
 		ERR("Unknown ust instrumentation type (%d)", ev->type);
 		ret = LTTNG_ERR_INVALID;
-		goto error_free_event;
+		goto error;
 	}
 
 	/* Copy event name */
@@ -507,7 +508,7 @@ enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 	default:
 		ERR("Unknown ust loglevel type (%d)", ev->loglevel_type);
 		ret = LTTNG_ERR_INVALID;
-		goto error_free_event;
+		goto error;
 	}
 
 	/* Same layout. */
@@ -523,12 +524,10 @@ enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 	     local_ust_event->attr.loglevel_type,
 	     local_ust_event->attr.loglevel);
 
-	*ust_event = local_ust_event;
+	*ust_event = local_ust_event.release();
 
 	return ret;
 
-error_free_event:
-	free(local_ust_event);
 error:
 	free(filter_expression);
 	free(filter);
@@ -1231,7 +1230,7 @@ void trace_ust_destroy_event(struct ltt_ust_event *event)
 	free(event->filter_expression);
 	free(event->filter);
 	free(event->exclusion);
-	free(event);
+	delete event;
 }
 
 /*
diff --git a/src/bin/lttng-sessiond/trace-ust.hpp b/src/bin/lttng-sessiond/trace-ust.hpp
index ea84722f1..778870717 100644
--- a/src/bin/lttng-sessiond/trace-ust.hpp
+++ b/src/bin/lttng-sessiond/trace-ust.hpp
@@ -40,19 +40,19 @@ struct ltt_ust_context {
 
 /* UST event */
 struct ltt_ust_event {
-	bool enabled;
-	struct lttng_ust_abi_event attr;
-	struct lttng_ht_node_str node;
-	char *filter_expression;
-	struct lttng_bytecode *filter;
-	struct lttng_event_exclusion *exclusion;
+	bool enabled = false;
+	struct lttng_ust_abi_event attr = {};
+	struct lttng_ht_node_str node = {};
+	char *filter_expression = nullptr;
+	struct lttng_bytecode *filter = nullptr;
+	struct lttng_event_exclusion *exclusion = nullptr;
 	/*
 	 * An internal event is an event which was created by the session daemon
 	 * through which, for example, events emitted in Agent domains are
 	 * "funelled". This is used to hide internal events from external
 	 * clients as they should never be modified by the external world.
 	 */
-	bool internal;
+	bool internal = false;
 };
 
 /* UST channel */