From: Ondřej Surý <ondrej@isc.org>
Date: Fri, 20 Mar 2026 01:15:17 +0000 (+0100)
Subject: Add MOVE_OWNERSHIP() macro for transferring pointer ownership
X-Git-Tag: v9.20.22~12^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8feefb9874a1e05da863c312a78bb68981160b2a;p=thirdparty%2Fbind9.git

Add MOVE_OWNERSHIP() macro for transferring pointer ownership

A helper macro that returns the current value of a pointer and sets
it to NULL in one expression, useful for transferring ownership in
designated initializers.

(cherry picked from commit 0f3be0beb8e461428466172d4b7b800933038adb)
---

diff --git a/lib/isc/include/isc/util.h b/lib/isc/include/isc/util.h
index 2e842f305d4..0a92afe2726 100644
--- a/lib/isc/include/isc/util.h
+++ b/lib/isc/include/isc/util.h
@@ -41,6 +41,13 @@
  *** General Macros.
  ***/
 
+#define MOVE_OWNERSHIP(source)                             \
+	({                                                 \
+		__typeof__(source) __ownership = (source); \
+		(source) = NULL;                           \
+		__ownership;                               \
+	})
+
 /*%
  * Legacy way how to hide unused function arguments, don't use in
  * the new code, rather use the ISC_ATTR_UNUSED macro that expands