shithub: choc

ref: 2d20dee9798613951023bc570104a6f80f0ef628
dir: /src/m_swap.c/

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// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// $Id: m_swap.c 255 2006-01-05 02:48:03Z fraggle $
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
// $Log$
// Revision 1.4  2006/01/05 02:48:03  fraggle
// Fixes for big endian machines (thanks locust)
//
// Revision 1.3  2005/07/23 18:56:07  fraggle
// Remove unneccessary pragmas
//
// Revision 1.2  2005/07/23 16:44:56  fraggle
// Update copyright to GNU GPL
//
// Revision 1.1.1.1  2005/07/23 16:19:58  fraggle
// Initial import
//
//
// DESCRIPTION:
//	Endianess handling, swapping 16bit and 32bit.
//
//-----------------------------------------------------------------------------

static const char
rcsid[] = "$Id: m_swap.c 255 2006-01-05 02:48:03Z fraggle $";


#include "m_swap.h"


// Not needed with big endian.
#ifndef WORDS_BIGENDIAN

// Swap 16bit, that is, MSB and LSB byte.
unsigned short SwapSHORT(unsigned short x)
{
    // No masking with 0xFF should be necessary. 
    return (x>>8) | (x<<8);
}

// Swapping 32bit.
unsigned long SwapLONG( unsigned long x)
{
    return
	(x>>24)
	| ((x>>8) & 0xff00)
	| ((x<<8) & 0xff0000)
	| (x<<24);
}


#endif