Add a "fork" of musl as //fusl.

fusl/include/endian.h

+#ifndef _ENDIAN_H
+#define _ENDIAN_H
+
+#include <features.h>
+
+#define __LITTLE_ENDIAN 1234
+#define __BIG_ENDIAN 4321
+#define __PDP_ENDIAN 3412
+
+#if defined(__GNUC__) && defined(__BYTE_ORDER__)
+#define __BYTE_ORDER __BYTE_ORDER__
+#else
+#include <bits/endian.h>
+#endif
+
+#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
+
+#define BIG_ENDIAN __BIG_ENDIAN
+#define LITTLE_ENDIAN __LITTLE_ENDIAN
+#define PDP_ENDIAN __PDP_ENDIAN
+#define BYTE_ORDER __BYTE_ORDER
+
+#include <stdint.h>
+
+static __inline uint16_t __bswap16(uint16_t __x)
+{
+        return __x<<8 | __x>>8;
+}
+
+static __inline uint32_t __bswap32(uint32_t __x)
+{
+        return __x>>24 | __x>>8&0xff00 | __x<<8&0xff0000 | __x<<24;
+}
+
+static __inline uint64_t __bswap64(uint64_t __x)
+{
+        return __bswap32(__x)+0ULL<<32 | __bswap32(__x>>32);
+}
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define htobe16(x) __bswap16(x)
+#define be16toh(x) __bswap16(x)
+#define betoh16(x) __bswap16(x)
+#define htobe32(x) __bswap32(x)
+#define be32toh(x) __bswap32(x)
+#define betoh32(x) __bswap32(x)
+#define htobe64(x) __bswap64(x)
+#define be64toh(x) __bswap64(x)
+#define betoh64(x) __bswap64(x)
+#define htole16(x) (uint16_t)(x)
+#define le16toh(x) (uint16_t)(x)
+#define letoh16(x) (uint16_t)(x)
+#define htole32(x) (uint32_t)(x)
+#define le32toh(x) (uint32_t)(x)
+#define letoh32(x) (uint32_t)(x)
+#define htole64(x) (uint64_t)(x)
+#define le64toh(x) (uint64_t)(x)
+#define letoh64(x) (uint64_t)(x)
+#else
+#define htobe16(x) (uint16_t)(x)
+#define be16toh(x) (uint16_t)(x)
+#define betoh16(x) (uint16_t)(x)
+#define htobe32(x) (uint32_t)(x)
+#define be32toh(x) (uint32_t)(x)
+#define betoh32(x) (uint32_t)(x)
+#define htobe64(x) (uint64_t)(x)
+#define be64toh(x) (uint64_t)(x)
+#define betoh64(x) (uint64_t)(x)
+#define htole16(x) __bswap16(x)
+#define le16toh(x) __bswap16(x)
+#define letoh16(x) __bswap16(x)
+#define htole32(x) __bswap32(x)
+#define le32toh(x) __bswap32(x)
+#define letoh32(x) __bswap32(x)
+#define htole64(x) __bswap64(x)
+#define le64toh(x) __bswap64(x)
+#define letoh64(x) __bswap64(x)
+#endif
+
+#endif
+
+#endif