From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Thu, 11 Mar 2021 21:00:19 +0000 (-0500)
Subject: Add structure size field to struct lttng_event
X-Git-Tag: v2.13.0-rc1~309
X-Git-Url: https://git.lttng.org/?a=commitdiff_plain;h=74579d3b9664fd1f60c0241cb569c6a2bfee05ff;p=lttng-ust.git

Add structure size field to struct lttng_event

Made possible by ABI bump. This scheme can be used for extensibility.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I38b15636605339f3f8702983aeaffafa1ab56719
---

diff --git a/include/lttng/ust-events.h b/include/lttng/ust-events.h
index d75a7323..37e5575e 100644
--- a/include/lttng/ust-events.h
+++ b/include/lttng/ust-events.h
@@ -395,6 +395,7 @@ struct lttng_bytecode_runtime {
 struct lttng_ust_event_private;
 
 struct lttng_event {
+	uint32_t struct_size;			/* Size of this structure. */
 	struct lttng_ust_event_private *priv;	/* Private event interface */
 
 	unsigned int id;
diff --git a/liblttng-ust/lttng-events.c b/liblttng-ust/lttng-events.c
index b024c4cf..d29a6c71 100644
--- a/liblttng-ust/lttng-events.c
+++ b/liblttng-ust/lttng-events.c
@@ -784,6 +784,7 @@ int lttng_event_create(const struct lttng_event_desc *desc,
 		ret = -ENOMEM;
 		goto cache_error;
 	}
+	event->struct_size = sizeof(struct lttng_event);
 	event_priv = zmalloc(sizeof(struct lttng_ust_event_private));
 	if (!event_priv) {
 		ret = -ENOMEM;