From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Fri, 5 May 2017 02:56:30 +0000 (-0400)
Subject: Add the container_of() macro to macro.h
X-Git-Tag: v2.10.0-rc1~47
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=93375aa60733caf9d30d45f4a0cff0c0394e46e9;p=lttng-tools.git

Add the container_of() macro to macro.h

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

diff --git a/src/common/macros.h b/src/common/macros.h
index 90849ed30..7eaf27cdf 100644
--- a/src/common/macros.h
+++ b/src/common/macros.h
@@ -20,6 +20,7 @@
 #define _MACROS_H
 
 #include <stdlib.h>
+#include <stddef.h>
 #include <string.h>
 #include <common/compat/string.h>
 
@@ -58,6 +59,14 @@ void *zmalloc(size_t len)
 #define ARRAY_SIZE(array)   (sizeof(array) / (sizeof((array)[0])))
 #endif
 
+#ifndef container_of
+#define container_of(ptr, type, member)					\
+	({								\
+		const typeof(((type *)NULL)->member) * __ptr = (ptr);	\
+		(type *)((char *)__ptr - offsetof(type, member));	\
+	})
+#endif
+
 #ifndef max
 #define max(a, b) ((a) > (b) ? (a) : (b))
 #endif