xenia-canary/src/xenia/base/byte_order.h

/**
 ******************************************************************************
 * Xenia : Xbox 360 Emulator Research Project                                 *
 ******************************************************************************
 * Copyright 2014 Ben Vanik. All rights reserved.                             *
 * Released under the BSD license - see LICENSE in the root for more details. *
 ******************************************************************************
 */

#ifndef XENIA_BASE_BYTE_ORDER_H_
#define XENIA_BASE_BYTE_ORDER_H_

#include <cstdint>

#include "xenia/base/platform.h"

#if XE_PLATFORM_MAC
#include <libkern/OSByteOrder.h>
#endif  // XE_PLATFORM_MAC

namespace xe {

#if XE_COMPILER_MSVC
#define XENIA_BASE_BYTE_SWAP_16 _byteswap_ushort
#define XENIA_BASE_BYTE_SWAP_32 _byteswap_ulong
#define XENIA_BASE_BYTE_SWAP_64 _byteswap_uint64
#elif XE_PLATFORM_MAC
#define XENIA_BASE_BYTE_SWAP_16 OSSwapInt16
#define XENIA_BASE_BYTE_SWAP_32 OSSwapInt32
#define XENIA_BASE_BYTE_SWAP_64 OSSwapInt64
#else
#define XENIA_BASE_BYTE_SWAP_16 __bswap_16
#define XENIA_BASE_BYTE_SWAP_32 __bswap_32
#define XENIA_BASE_BYTE_SWAP_64 __bswap_64
#endif  // XE_COMPILER_MSVC

inline int8_t byte_swap(int8_t value) { return value; }
inline uint8_t byte_swap(uint8_t value) { return value; }
inline int16_t byte_swap(int16_t value) {
  return static_cast<int16_t>(
      XENIA_BASE_BYTE_SWAP_16(static_cast<int16_t>(value)));
}
inline uint16_t byte_swap(uint16_t value) {
  return XENIA_BASE_BYTE_SWAP_16(value);
}
inline uint16_t byte_swap(wchar_t value) {
  return static_cast<wchar_t>(XENIA_BASE_BYTE_SWAP_16(value));
}
inline int32_t byte_swap(int32_t value) {
  return static_cast<int32_t>(
      XENIA_BASE_BYTE_SWAP_32(static_cast<int32_t>(value)));
}
inline uint32_t byte_swap(uint32_t value) {
  return XENIA_BASE_BYTE_SWAP_32(value);
}
inline int64_t byte_swap(int64_t value) {
  return static_cast<int64_t>(
      XENIA_BASE_BYTE_SWAP_64(static_cast<int64_t>(value)));
}
inline uint64_t byte_swap(uint64_t value) {
  return XENIA_BASE_BYTE_SWAP_64(value);
}
inline float byte_swap(float value) {
  uint32_t temp = byte_swap(*reinterpret_cast<uint32_t *>(&value));
  return *reinterpret_cast<float *>(&temp);
}
inline double byte_swap(double value) {
  uint64_t temp = byte_swap(*reinterpret_cast<uint64_t *>(&value));
  return *reinterpret_cast<double *>(&temp);
}
template <typename T>
inline T byte_swap(T value) {
  if (sizeof(T) == 4) {
    return static_cast<T>(byte_swap(static_cast<uint32_t>(value)));
  } else {
    assert_always("not handled");
  }
}

template <typename T>
struct be {
  be() = default;
  be(const T &src) : value(xe::byte_swap(src)) {}
  be(const be &other) { value = other.value; }
  operator T() const { return xe::byte_swap(value); }

  be<T>& operator+=(int a) { *this = *this + a; return *this; }
  be<T>& operator-=(int a) { *this = *this - a; return *this; }
  be<T>& operator++() { *this += 1; return *this; } // ++a
  be<T> operator++(int) { *this += 1; return (*this - 1); } // a++
  be<T>& operator--() { *this -= 1; return *this; } // --a
  be<T> operator--(int) { *this -= 1; return (*this + 1); } // a--

  T value;
};

}  // namespace xe

#endif  // XENIA_BASE_BYTE_ORDER_H_