endian.h

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//===-- Definition of macros from endian.h --------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
 
#ifndef __CLANG_ENDIAN_H
#define __CLANG_ENDIAN_H
 
// If the system has an endian.h, let's use that instead.
#if __has_include_next(<endian.h>)
#include_next <endian.h>
#else
 
#include <stdint.h>
 
// Implementation taken from llvm libc endian-macros.h.
#ifdef __cplusplus
#define __CLANG_ENDIAN_CAST(cast, type, value) (cast<type>(value))
#else
#define __CLANG_ENDIAN_CAST(cast, type, value) ((type)(value))
#endif
 
#define LITTLE_ENDIAN __ORDER_LITTLE_ENDIAN__
#define BIG_ENDIAN __ORDER_BIG_ENDIAN__
#define PDP_ENDIAN __ORDER_PDP_ENDIAN__
#define BYTE_ORDER __BYTE_ORDER__
 
// Define some compatibility macros if they are not defined.
#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
#ifndef __PDP_ENDIAN
#define __PDP_ENDIAN PDP_ENDIAN
#endif
 
#if BYTE_ORDER == LITTLE_ENDIAN
 
#define htobe16(x)                                                             \
  __builtin_bswap16(__CLANG_ENDIAN_CAST(static_cast, uint16_t, x))
#define htobe32(x)                                                             \
  __builtin_bswap32(__CLANG_ENDIAN_CAST(static_cast, uint32_t, x))
#define htobe64(x)                                                             \
  __builtin_bswap64(__CLANG_ENDIAN_CAST(static_cast, uint64_t, x))
#define htole16(x) __CLANG_ENDIAN_CAST(static_cast, uint16_t, x)
#define htole32(x) __CLANG_ENDIAN_CAST(static_cast, uint32_t, x)
#define htole64(x) __CLANG_ENDIAN_CAST(static_cast, uint64_t, x)
#define be16toh(x)                                                             \
  __builtin_bswap16(__CLANG_ENDIAN_CAST(static_cast, uint16_t, x))
#define be32toh(x)                                                             \
  __builtin_bswap32(__CLANG_ENDIAN_CAST(static_cast, uint32_t, x))
#define be64toh(x)                                                             \
  __builtin_bswap64(__CLANG_ENDIAN_CAST(static_cast, uint64_t, x))
#define le16toh(x) __CLANG_ENDIAN_CAST(static_cast, uint16_t, x)
#define le32toh(x) __CLANG_ENDIAN_CAST(static_cast, uint32_t, x)
#define le64toh(x) __CLANG_ENDIAN_CAST(static_cast, uint64_t, x)
 
#elif BYTE_ORDER == BIG_ENDIAN
 
#define htobe16(x) __CLANG_ENDIAN_CAST(static_cast, uint16_t, x)
#define htobe32(x) __CLANG_ENDIAN_CAST(static_cast, uint32_t, x)
#define htobe64(x) __CLANG_ENDIAN_CAST(static_cast, uint64_t, x)
#define htole16(x)                                                             \
  __builtin_bswap16(__CLANG_ENDIAN_CAST(static_cast, uint16_t, x))
#define htole32(x)                                                             \
  __builtin_bswap32(__CLANG_ENDIAN_CAST(static_cast, uint32_t, x))
#define htole64(x)                                                             \
  __builtin_bswap64(__CLANG_ENDIAN_CAST(static_cast, uint64_t, x))
#define be16toh(x) __CLANG_ENDIAN_CAST(static_cast, uint16_t, x)
#define be32toh(x) __CLANG_ENDIAN_CAST(static_cast, uint32_t, x)
#define be64toh(x) __CLANG_ENDIAN_CAST(static_cast, uint64_t, x)
#define le16toh(x)                                                             \
  __builtin_bswap16(__CLANG_ENDIAN_CAST(static_cast, uint16_t, x))
#define le32toh(x)                                                             \
  __builtin_bswap32(__CLANG_ENDIAN_CAST(static_cast, uint32_t, x))
#define le64toh(x)                                                             \
  __builtin_bswap64(__CLANG_ENDIAN_CAST(static_cast, uint64_t, x))
 
#else
#error "Unsupported endianness"
#endif
#endif // __has_include_next
#endif // __CLANG_ENDIAN_H