diff --git a/src/byteswap.hpp b/src/byteswap.hpp
new file mode 100644
index 0000000..1a0e534
--- /dev/null
+++ b/src/byteswap.hpp
@@ -0,0 +1,11 @@
+#pragma once
+
+#ifdef _MSC_VER
+# include <stdlib.h>
+# define bswap_64(x) _byteswap_uint64(x)
+#elif defined(__APPLE__)
+# include <libkern/OSByteOrder.h>
+# define bswap_64(x) OSSwapInt64(x)
+#else
+# include <byteswap.h>
+#endif
diff --git a/src/crypto/bigint.cpp b/src/crypto/bigint.cpp
index b76ba92..5bc96d4 100644
--- a/src/crypto/bigint.cpp
+++ b/src/crypto/bigint.cpp
@@ -5,16 +5,7 @@
 #include <fc/crypto/base64.hpp>
 
 #include <fc/exception/exception.hpp>
-
-#ifdef _MSC_VER
-# include <stdlib.h>
-# define bswap_64(x) _byteswap_uint64(x)
-#elif defined(__APPLE__)
-# include <libkern/OSByteOrder.h>
-# define bswap_64(x) OSSwapInt64(x)
-#else
-# include <byteswap.h>
-#endif
+#include "../byteswap.hpp"
 
 namespace fc {
       bigint::bigint( const char* bige, uint32_t l ) {
diff --git a/src/uint128.cpp b/src/uint128.cpp
index 2912644..c989d3f 100644
--- a/src/uint128.cpp
+++ b/src/uint128.cpp
@@ -2,11 +2,7 @@
 #include <fc/variant.hpp>
 #include <fc/crypto/bigint.hpp>
 #include <stdexcept>
-#ifdef WIN32
-#include <WinSock2.h>
-#else
-#include <arpa/inet.h>
-#endif
+#include "byteswap.hpp"
 
 namespace fc 
 {
@@ -118,10 +114,9 @@ namespace fc
     }
 
 
-    #define bswap64(y) (((uint64_t)ntohl(y)) << 32 | ntohl(y>>32))
     uint128::operator bigint()const
     {
-       auto tmp  = uint128( bswap64( hi ), bswap64( lo ) );
+       auto tmp  = uint128( bswap_64( hi ), bswap_64( lo ) );
        bigint bi( (char*)&tmp, sizeof(tmp) );
        return bi;
     }