1 files changed, 2 insertions, 0 deletions

diff --git a/toxcore/network.h b/toxcore/network.h
index bf14f319..e33e111f 100644
--- a/toxcore/network.h
+++ b/toxcore/network.h
@@ -174,6 +174,8 @@ typedef struct __attribute__ ((__packed__)) __attribute__((gcc_struct))
 }
 IP_Port;
 
+/* Does the IP6 struct a contain an IPv4 address in an IPv6 one? */
+#define IPV6_IPV4_IN_V6(a) ((a.uint64[0] == 0) && (a.uint32[2] == htonl (0xffff)))
 
 #define SIZE_IP4 4
 #define SIZE_IP6 16