// // byteswap.cpp // // Copyright (c) Microsoft Corporation. All rights reserved. // // Defines functions that swap the bytes of an unsigned integer. // #include <stdlib.h> #pragma function(_byteswap_ulong, _byteswap_uint64, _byteswap_ushort) /*** *unsigned long _byteswap_ulong(i) - long byteswap * *Purpose: * Performs a byte swap on an unsigned integer. * *Entry: * unsigned long i: value to swap * *Exit: * returns swaped * *Exceptions: * None. * *******************************************************************************/ extern "C" unsigned long __cdecl _byteswap_ulong(unsigned long const i) { unsigned int j; j = (i << 24); j += (i << 8) & 0x00FF0000; j += (i >> 8) & 0x0000FF00; j += (i >> 24); return j; } extern "C" unsigned short __cdecl _byteswap_ushort(unsigned short const i) { unsigned short j; j = (i << 8); j += (i >> 8); return j; } extern "C" unsigned __int64 __cdecl _byteswap_uint64(unsigned __int64 const i) { unsigned __int64 j; j = (i << 56); j += (i << 40) & 0x00FF000000000000; j += (i << 24) & 0x0000FF0000000000; j += (i << 8) & 0x000000FF00000000; j += (i >> 8) & 0x00000000FF000000; j += (i >> 24) & 0x0000000000FF0000; j += (i >> 40) & 0x000000000000FF00; j += (i >> 56); return j; }