+#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define betoh16(x) __bswap16(x)
+#define betoh32(x) __bswap32(x)
+#define betoh64(x) __bswap64(x)
+#define letoh16(x) (uint16_t)(x)
+#define letoh32(x) (uint32_t)(x)
+#define letoh64(x) (uint64_t)(x)
+#else
+#define betoh16(x) (uint16_t)(x)
+#define betoh32(x) (uint32_t)(x)
+#define betoh64(x) (uint64_t)(x)
+#define letoh16(x) __bswap16(x)
+#define letoh32(x) __bswap32(x)
+#define letoh64(x) __bswap64(x)
+#endif