From 3149cde3aa7f87298db3e256e784e6ca6fb76882 Mon Sep 17 00:00:00 2001
From: Philippe Proulx <eeppeliteloop@gmail.com>
Date: Mon, 20 Jan 2020 16:59:05 -0500
Subject: [PATCH] lib: bt_version_get_extra(): return `NULL` if none instead of
 empty str.

This follows the pattern we have for other optional strings returned by
the library.

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Change-Id: I775f4f3be917bde405ad3b5e63183dae9609cf03
Reviewed-on: https://review.lttng.org/c/babeltrace/+/2833
Reviewed-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Tested-by: jenkins <jenkins@lttng.org>
---
 include/babeltrace2/version.h | 8 +-------
 src/lib/babeltrace2.c         | 3 ++-
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/include/babeltrace2/version.h b/include/babeltrace2/version.h
index 7cd0213f..875fa2a7 100644
--- a/include/babeltrace2/version.h
+++ b/include/babeltrace2/version.h
@@ -92,13 +92,7 @@ This extra information can contain a version suffix such as
 <code>-pre5</code> or <code>-rc1</code>.
 
 @returns
-    @parblock
-    Extra information about the library's version.
-
-    Cannot be \c NULL.
-
-    Can be an empty string if there's no extra information.
-    @endparblock
+    Extra information about the library's version, or \c NULL if none.
 */
 extern const char *bt_version_get_extra(void);
 
diff --git a/src/lib/babeltrace2.c b/src/lib/babeltrace2.c
index 14572c29..8216cd11 100644
--- a/src/lib/babeltrace2.c
+++ b/src/lib/babeltrace2.c
@@ -24,6 +24,7 @@
 
 #include <babeltrace2/babeltrace.h>
 #include <stdlib.h>
+#include <string.h>
 
 unsigned int bt_version_get_major(void)
 {
@@ -41,5 +42,5 @@ unsigned int bt_version_get_patch(void) {
 
 const char *bt_version_get_extra(void)
 {
-	return BT_VERSION_EXTRA;
+	return strlen(BT_VERSION_EXTRA) == 0 ? NULL : BT_VERSION_EXTRA;
 }
-- 
2.34.1