diff --git a/src/m_swap.h b/src/m_swap.h
index c1e5e39b7..faa54e0b2 100644
--- a/src/m_swap.h
+++ b/src/m_swap.h
@@ -44,4 +44,13 @@
 #define MSBF_LONG SWAP_LONG
 #endif
 
+// Big to little endian
+#ifdef SRB2_LITTLE_ENDIAN
+	#define BIGENDIAN_LONG(x) ((INT32)(((x)>>24)&0xff)|(((x)<<8)&0xff0000)|(((x)>>8)&0xff00)|(((x)<<24)&0xff000000))
+	#define BIGENDIAN_SHORT(x) ((INT16)(((x)>>8)|((x)<<8)))
+#else
+	#define BIGENDIAN_LONG(x) ((INT32)(x))
+	#define BIGENDIAN_SHORT(x) ((INT16)(x))
+#endif
+
 #endif