--- /dev/null
+# endian.h
+
+This provides the endian conversion functions form endian.h on Windows, Linux,
+*BSD, and Mac OS X. You still need to use `-std=gnu99` instead of `-std=c99`
+for gcc. The functions might actually be macros. Functions: htobe16, htole16,
+be16toh, le16toh, htobe32, htole32, be32toh, le32toh, htobe64, htole64,
+be64toh, le64toh.
+
+The implementation was written by Mathias Panzenböck and published in this
+[Gist][gist].
+
+## Install
+
+Install with [clib(1)]:
+
+```sh
+clib install mikepb/endian.h
+```
+
+## Usage
+
+```c
+#include <stdint.h>
+#include "endian.h"
+
+uint32_t endian32(const uint32_t i) {
+ return be32toh(i);
+}
+```
+
+## License
+
+Public Domain
+
+[clib]: https://github.com/clibs/clib
+[gist]: https://gist.github.com/panzi/6856583
--- /dev/null
+//
+// endian.h
+//
+// https://gist.github.com/panzi/6856583
+//
+// I, Mathias Panzenböck, place this file hereby into the public domain. Use
+// it at your own risk for whatever you like. In case there are
+// jurisdictions that don't support putting things in the public domain you
+// can also consider it to be "dual licensed" under the BSD, MIT and Apache
+// licenses, if you want to. This code is trivial anyway. Consider it an
+// example on how to get the endian conversion functions on different
+// platforms.
+
+#ifndef PORTABLE_ENDIAN_H__
+#define PORTABLE_ENDIAN_H__
+
+#if (defined(_WIN16) || defined(_WIN32) || defined(_WIN64)) && !defined(__WINDOWS__)
+
+# define __WINDOWS__
+
+#endif
+
+#if defined(__linux__) || defined(__CYGWIN__)
+
+# include <endian.h>
+
+#elif defined(__APPLE__)
+
+# include <libkern/OSByteOrder.h>
+
+# define htobe16(x) OSSwapHostToBigInt16(x)
+# define htole16(x) OSSwapHostToLittleInt16(x)
+# define be16toh(x) OSSwapBigToHostInt16(x)
+# define le16toh(x) OSSwapLittleToHostInt16(x)
+
+# define htobe32(x) OSSwapHostToBigInt32(x)
+# define htole32(x) OSSwapHostToLittleInt32(x)
+# define be32toh(x) OSSwapBigToHostInt32(x)
+# define le32toh(x) OSSwapLittleToHostInt32(x)
+
+# define htobe64(x) OSSwapHostToBigInt64(x)
+# define htole64(x) OSSwapHostToLittleInt64(x)
+# define be64toh(x) OSSwapBigToHostInt64(x)
+# define le64toh(x) OSSwapLittleToHostInt64(x)
+
+# define __BYTE_ORDER BYTE_ORDER
+# define __BIG_ENDIAN BIG_ENDIAN
+# define __LITTLE_ENDIAN LITTLE_ENDIAN
+# define __PDP_ENDIAN PDP_ENDIAN
+
+#elif defined(__OpenBSD__)
+
+# include <sys/endian.h>
+
+#elif defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
+
+# include <sys/endian.h>
+
+# define be16toh(x) betoh16(x)
+# define le16toh(x) letoh16(x)
+
+# define be32toh(x) betoh32(x)
+# define le32toh(x) letoh32(x)
+
+# define be64toh(x) betoh64(x)
+# define le64toh(x) letoh64(x)
+
+#elif defined(__WINDOWS__)
+
+# include <winsock2.h>
+# include <sys/param.h>
+
+# if BYTE_ORDER == LITTLE_ENDIAN
+
+# define htobe16(x) htons(x)
+# define htole16(x) (x)
+# define be16toh(x) ntohs(x)
+# define le16toh(x) (x)
+
+# define htobe32(x) htonl(x)
+# define htole32(x) (x)
+# define be32toh(x) ntohl(x)
+# define le32toh(x) (x)
+
+# define htobe64(x) htonll(x)
+# define htole64(x) (x)
+# define be64toh(x) ntohll(x)
+# define le64toh(x) (x)
+
+# elif BYTE_ORDER == BIG_ENDIAN
+
+ /* that would be xbox 360 */
+# define htobe16(x) (x)
+# define htole16(x) __builtin_bswap16(x)
+# define be16toh(x) (x)
+# define le16toh(x) __builtin_bswap16(x)
+
+# define htobe32(x) (x)
+# define htole32(x) __builtin_bswap32(x)
+# define be32toh(x) (x)
+# define le32toh(x) __builtin_bswap32(x)
+
+# define htobe64(x) (x)
+# define htole64(x) __builtin_bswap64(x)
+# define be64toh(x) (x)
+# define le64toh(x) __builtin_bswap64(x)
+
+# else
+
+# error byte order not supported
+
+# endif
+
+# define __BYTE_ORDER BYTE_ORDER
+# define __BIG_ENDIAN BIG_ENDIAN
+# define __LITTLE_ENDIAN LITTLE_ENDIAN
+# define __PDP_ENDIAN PDP_ENDIAN
+
+#else
+
+# error platform not supported
+
+#endif
+
+#endif