Supermodel/Src/Util/ByteSwap.cpp

#include "Util/ByteSwap.h"
#ifdef _MSC_VER
#include <intrin.h>
#endif

namespace Util
{
  void FlipEndian16(uint8_t * const buffer, const size_t size)
  {
#ifdef _MSC_VER
    uint16_t * const buffer16 = (uint16_t*)buffer;
    for (size_t i = 0; i < size/2; i++)
      buffer16[i] = _byteswap_ushort(buffer16[i]);
#elif 1 // assume GCC
    uint16_t * const buffer16 = (uint16_t*)buffer;
    for (size_t i = 0; i < size/2; i++)
      buffer16[i] = __builtin_bswap16(buffer16[i]);
#else
    for (size_t i = 0; i < (size & ~1); i += 2)
    {
      uint8_t tmp = buffer[i + 0];
      buffer[i + 0] = buffer[i + 1];
      buffer[i + 1] = tmp;
    }
#endif
  }

  void FlipEndian32(uint8_t * const buffer, const size_t size)
  {
#ifdef _MSC_VER
    uint32_t * const buffer32 = (uint32_t*)buffer;
    for (size_t i = 0; i < size/4; i++)
      buffer32[i] = _byteswap_ulong(buffer32[i]);
#elif 1 // assume GCC
    uint32_t * const buffer32 = (uint32_t*)buffer;
    for (size_t i = 0; i < size/4; i++)
      buffer32[i] = __builtin_bswap32(buffer32[i]);
#else
    for (size_t i = 0; i < (size & ~3); i += 4)
    {
      uint8_t tmp1 = buffer[i+0];
      uint8_t tmp2 = buffer[i+1];
      buffer[i+0] = buffer[i+3];
      buffer[i+1] = buffer[i+2];
      buffer[i+2] = tmp2;
      buffer[i+3] = tmp1;
    }
#endif
  }
} // Util