server: add a file for commonly used macros

Add a file to the server-side for commonly used macros.

Signed-off-by: Danny Holman <dholman@gymli.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/server/include/util.h b/server/include/util.h
new file mode 100644
index 0000000..edadc5a
--- /dev/null
+++ b/server/include/util.h
@@ -0,0 +1,8 @@
+#ifndef MRAT_UTIL_H
+#define MRAT_UTIL_H
+
+#define container_of(ptr, type, member) ({                      \
+        const typeof(((type*)0)->member)*__mptr = (ptr);        \
+        (type*)((char*)__mptr - offsetof(type, member)); })
+
+#endif