diff --git a/include/compat/endian.h b/include/compat/endian.h
index cd85f5c..6dfe0b0 100644
--- a/include/compat/endian.h
+++ b/include/compat/endian.h
@@ -48,4 +48,65 @@
 #endif
 #endif
 
+#if defined(__APPLE__) && !defined(HAVE_ENDIAN_H)
+#include <libkern/OSByteOrder.h>
+#define betoh16(x) OSSwapBigToHostInt16((x))
+#define htobe16(x) OSSwapHostToBigInt16((x))
+#define betoh32(x) OSSwapBigToHostInt32((x))
+#define htobe32(x) OSSwapHostToBigInt32(x)
+#define htole64(x) OSSwapHostToLittleInt64(x)
+#define htobe64(x) OSSwapHostToBigInt64(x)
+#define letoh64(x) OSSwapLittleToHostInt64(x)
+#define betoh64(x) OSSwapBigToHostInt64(x)
+#endif /* __APPLE__ && !HAVE_ENDIAN_H */
+
+#if defined(_WIN32) && !defined(HAVE_ENDIAN_H)
+#include <winsock2.h>
+#define betoh16(x) ntohs((x))
+#define htobe16(x) htons((x))
+#define betoh32(x) ntohl((x))
+#define htobe32(x) ntohl((x))
+#define betoh64(x) ntohll((x))
+#define htobe64(x) ntohll((x))
+#endif /* _WIN32 && !HAVE_ENDIAN_H */
+
+#ifdef __linux__
+#if !defined(betoh16)
+#define betoh16	be16toh
+#endif
+#if !defined(betoh32)
+#define betoh32	be32toh
+#endif
+#if !defined(betoh64)
+#define betoh64	be64toh
+#endif
+#endif /* __linux__ */
+
+#if defined(__FreeBSD__)
+#if !defined(HAVE_ENDIAN_H)
+#include <sys/endian.h>
+#endif
+#if !defined(betoh16)
+#define betoh16	be16toh
+#endif
+#if !defined(betoh32)
+#define betoh32	be32toh
+#endif
+#if !defined(betoh64)
+#define betoh64	be64toh
+#endif
+#endif
+
+#if defined(__NetBSD__)
+#if !defined(betoh16)
+#define betoh16	be16toh
+#endif
+#if !defined(betoh32)
+#define betoh32	be32toh
+#endif
+#if !defined(betoh64)
+#define betoh64	be64toh
+#endif
+#endif
+
 #endif