common: third iteration of ipv6 netadr_t, now binary compatible with v4-to-v6 mapped addresses

common/netadr.h

@@ -21,7 +21,7 @@
 
 typedef enum
 {
-	NA_UNUSED,
+	NA_UNUSED = 0,
 	NA_LOOPBACK,
 	NA_BROADCAST,
 	NA_IP,
@@ -50,23 +50,20 @@ typedef struct netadr_s
 		struct
 		{
 			uint32_t type;
-			uint8_t  ip[4];
-			uint8_t  ipx[10];
 		};
 		struct
 		{
 #if XASH_LITTLE_ENDIAN
 			uint16_t type6;
-			uint8_t ip6_0[2];
+			uint8_t ip6_10[2]; // or 10-th two IPv6 octets
 #elif XASH_BIG_ENDIAN
-			uint8_t ip6_0[2];
+			uint8_t ip6_10[2]; // or 10-th two IPv6 octets
 			uint16_t type6;
-#else
-#error
 #endif
-			uint8_t ip6_1[14];
 		};
 	};
+	uint8_t  ip[4];   // or last 4 IPv6 octets
+	uint8_t  ipx[10]; // or first 10 IPv6 octets
 	uint16_t port;
 } netadr_t;
 #pragma pack( pop )