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/*
* stdendian.h
*
* This header defines the following endian macros as defined here:
* http://austingroupbugs.net/view.php?id=162
*
* BYTE_ORDER this macro shall have a value equal to one
* of the *_ENDIAN macros in this header.
* LITTLE_ENDIAN if BYTE_ORDER == LITTLE_ENDIAN, the host
* byte order is from least significant to
* most significant.
* BIG_ENDIAN if BYTE_ORDER == BIG_ENDIAN, the host byte
* order is from most significant to least
* significant.
*
* The following are defined as macros:
*
* uint16_t bswap16(uint16_t x);
* uint32_t bswap32(uint32_t x);
* uint64_t bswap64(uint64_t x);
* uint16_t htobe16(uint16_t x);
* uint16_t htole16(uint16_t x);
* uint16_t be16toh(uint16_t x);
* uint16_t le16toh(uint16_t x);
*
* uint32_t htobe32(uint32_t x);
* uint32_t htole32(uint32_t x);
* uint32_t be32toh(uint32_t x);
* uint32_t le32toh(uint32_t x);
*
* uint64_t htobe64(uint64_t x);
* uint64_t htole64(uint64_t x);
* uint64_t be64toh(uint64_t x);
* uint64_t le64toh(uint64_t x);
*
* The header defines the following macro for OpenCL compatibility
* https://www.khronos.org/registry/cl/sdk/2.0/docs/man/xhtml/preprocessorDirectives.html
*
* __ENDIAN_LITTLE__ if BYTE_ORDER == LITTLE_ENDIAN then this
* macro is present for OpenCL compatibility
*
* The implementation provides a uniform interface to endian macros using only
* system headers on recent Linux, Darwin, FreeBSD, Solaris and Windows systems.
*
* This approach is intended to avoid the need for preflight configure scripts.
* An alternative approach would be to test compiler CPU architecture marcros.
*
* This header has had *limited* testing on recent C11/C++11 compilers and is
* based on the austin bug tracker interface, manpages, and headers present in
* Linux, FreeBSD, Windows, Solaris and Darwin.
*
* The header uses __builtin_bswapXX intrinsic with GCC/Clang (__GNUC__) on
* platforms that do not provide bswap16, bswap32, bswap64 (Darwin)
*
* Public Domain.
*/
/* requires C11 or C++11 */
#if defined (__cplusplus)
#include <cstdint>
#elif !defined (__OPENCL_VERSION__)
#include <stdint.h>
#endif
/* Linux / GLIBC */
#if defined(__linux__) || defined(__GLIBC__)
#include <endian.h>
#include <byteswap.h>
#define __ENDIAN_DEFINED 1
#define __BSWAP_DEFINED 1
#define __HOSTSWAP_DEFINED 1
#define _BYTE_ORDER __BYTE_ORDER
#define _LITTLE_ENDIAN __LITTLE_ENDIAN
#define _BIG_ENDIAN __BIG_ENDIAN
#define bswap16(x) bswap_16(x)
#define bswap32(x) bswap_32(x)
#define bswap64(x) bswap_64(x)
#endif /* __linux__ || __GLIBC__ */
/* BSD */
#if defined(__FreeBSD__) || defined(__NetBSD__) || \
defined(__DragonFly__) || defined(__OpenBSD__)
#include <sys/endian.h>
#define __ENDIAN_DEFINED 1
#define __BSWAP_DEFINED 1
#define __HOSTSWAP_DEFINED 1
#endif /* BSD */
/* Solaris */
#if defined (sun)
#include <sys/isa_defs.h>
/* sun headers don't set a value for _LITTLE_ENDIAN or _BIG_ENDIAN */
#if defined(_LITTLE_ENDIAN)
#undef _LITTLE_ENDIAN
#define _LITTLE_ENDIAN 1234
#define _BIG_ENDIAN 4321
#define _BYTE_ORDER _LITTLE_ENDIAN
#elif defined(_BIG_ENDIAN)
#undef _BIG_ENDIAN
#define _LITTLE_ENDIAN 1234
#define _BIG_ENDIAN 4321
#define _BYTE_ORDER _BIG_ENDIAN
#endif
#define __ENDIAN_DEFINED 1
#endif /* sun */
/* Windows */
#if defined(_WIN32) || defined(_MSC_VER)
/* assumes all Microsoft targets are little endian */
#define _LITTLE_ENDIAN 1234
#define _BIG_ENDIAN 4321
#define _BYTE_ORDER _LITTLE_ENDIAN
#define __ENDIAN_DEFINED 1
#endif /* _MSC_VER */
/* OS X */
#if defined(__APPLE__)
#include <machine/endian.h>
#define _BYTE_ORDER BYTE_ORDER
#define _LITTLE_ENDIAN LITTLE_ENDIAN
#define _BIG_ENDIAN BIG_ENDIAN
#define __ENDIAN_DEFINED 1
#endif /* __APPLE__ */
/* OpenCL */
#if defined (__OPENCL_VERSION__)
#define _LITTLE_ENDIAN 1234
#define __BIG_ENDIAN 4321
#if defined (__ENDIAN_LITTLE__)
#define _BYTE_ORDER _LITTLE_ENDIAN
#else
#define _BYTE_ORDER _BIG_ENDIAN
#endif
#define bswap16(x) as_ushort(as_uchar2(ushort(x)).s1s0)
#define bswap32(x) as_uint(as_uchar4(uint(x)).s3s2s1s0)
#define bswap64(x) as_ulong(as_uchar8(ulong(x)).s7s6s5s4s3s2s1s0)
#define __ENDIAN_DEFINED 1
#define __BSWAP_DEFINED 1
#endif
/* Unknown */
#if !__ENDIAN_DEFINED
#error Could not determine CPU byte order
#endif
/* POSIX - http://austingroupbugs.net/view.php?id=162 */
#ifndef BYTE_ORDER
#define BYTE_ORDER _BYTE_ORDER
#endif
#ifndef LITTLE_ENDIAN
#define LITTLE_ENDIAN _LITTLE_ENDIAN
#endif
#ifndef BIG_ENDIAN
#define BIG_ENDIAN _BIG_ENDIAN
#endif
/* OpenCL compatibility - define __ENDIAN_LITTLE__ on little endian systems */
#if _BYTE_ORDER == _LITTLE_ENDIAN
#if !defined (__ENDIAN_LITTLE__)
#define __ENDIAN_LITTLE__ 1
#endif
#endif
/* Byte swap macros */
#if !__BSWAP_DEFINED
#ifndef bswap16
/* handle missing __builtin_bswap16 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52624 */
#if defined __GNUC__
#define bswap16(x) __builtin_bswap16(x)
#else
#define bswap16(x) ((uint16_t)((((uint16_t) (x) & 0xff00) >> 8) | \
(((uint16_t) (x) & 0x00ff) << 8)))
#endif
#endif
#ifndef bswap32
#if defined __GNUC__
#define bswap32(x) __builtin_bswap32(x)
#else
#define bswap32(x) ((uint32_t)((((uint32_t) (x) & 0xff000000) >> 24) | \
(((uint32_t) (x) & 0x00ff0000) >> 8) | \
(((uint32_t) (x) & 0x0000ff00) << 8) | \
(((uint32_t) (x) & 0x000000ff) << 24)))
#endif
#endif
#ifndef bswap64
#if defined __GNUC__
#define bswap64(x) __builtin_bswap64(x)
#else
#define bswap64(x) ((uint64_t)((((uint64_t) (x) & 0xff00000000000000ull) >> 56) | \
(((uint64_t) (x) & 0x00ff000000000000ull) >> 40) | \
(((uint64_t) (x) & 0x0000ff0000000000ull) >> 24) | \
(((uint64_t) (x) & 0x000000ff00000000ull) >> 8) | \
(((uint64_t) (x) & 0x00000000ff000000ull) << 8) | \
(((uint64_t) (x) & 0x0000000000ff0000ull) << 24) | \
(((uint64_t) (x) & 0x000000000000ff00ull) << 40) | \
(((uint64_t) (x) & 0x00000000000000ffull) << 56)))
#endif
#endif
#endif
/* Host swap macros */
#ifndef __HOSTSWAP_DEFINED
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define htobe16(x) bswap16((x))
#define htole16(x) ((uint16_t)(x))
#define be16toh(x) bswap16((x))
#define le16toh(x) ((uint16_t)(x))
#define htobe32(x) bswap32((x))
#define htole32(x) ((uint32_t)(x))
#define be32toh(x) bswap32((x))
#define le32toh(x) ((uint32_t)(x))
#define htobe64(x) bswap64((x))
#define htole64(x) ((uint64_t)(x))
#define be64toh(x) bswap64((x))
#define le64toh(x) ((uint64_t)(x))
#elif __BYTE_ORDER == __BIG_ENDIAN
#define htobe16(x) ((uint16_t)(x))
#define htole16(x) bswap16((x))
#define be16toh(x) ((uint16_t)(x))
#define le16toh(x) bswap16((x))
#define htobe32(x) ((uint32_t)(x))
#define htole32(x) bswap32((x))
#define be32toh(x) ((uint32_t)(x))
#define le64toh(x) bswap64((x))
#define htobe64(x) ((uint64_t)(x))
#define htole64(x) bswap64((x))
#define be64toh(x) ((uint64_t)(x))
#define le32toh(x) bswap32((x))
#endif
#endif
/*
#include <stdio.h>
#include <stdendian.h>
int main()
{
#if BYTE_ORDER == LITTLE_ENDIAN
printf("little endian\n");
#endif
#if BYTE_ORDER == BIG_ENDIAN
printf("big endian\n");
#endif
printf("bswap16(%04x) %04x\n", 0xf0e0, bswap16(0xf0e0));
printf("htobe16(%04x) %04x\n", 0xf0e0, htobe16(0xf0e0));
printf("htole16(%04x) %04x\n", 0xf0e0, htole16(0xf0e0));
printf("bswap32(%08x) %08x\n", 0xf0e0d0c0, bswap32(0xf0e0d0c0));
printf("htobe32(%08x) %08x\n", 0xf0e0d0c0, htobe32(0xf0e0d0c0));
printf("htole32(%08x) %08x\n", 0xf0e0d0c0, htole32(0xf0e0d0c0));
printf("bswap64(%016llx) %016llx\n", 0xf0e0d0c0b0a09080ULL, bswap64(0xf0e0d0c0b0a09080ULL));
printf("htobe64(%016llx) %016llx\n", 0xf0e0d0c0b0a09080ULL, htobe64(0xf0e0d0c0b0a09080ULL));
printf("htole64(%016llx) %016llx\n", 0xf0e0d0c0b0a09080ULL, htole64(0xf0e0d0c0b0a09080ULL));
}
*/
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