i_swap.h

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//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005-2014 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.
//
// DESCRIPTION:
//  Endianess handling, swapping 16bit and 32bit.
//
 
 
#ifndef __I_SWAP__
#define __I_SWAP__
 
#ifdef __DJGPP__
 
 
#define SHORT(x)  ((signed short) (x))
#define LONG(x)   ((signed int) (x))
 
#define SYS_LITTLE_ENDIAN
 
 
#else  // __DJGPP__
 
 
#if ( __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ )
#define SYS_LITTLE_ENDIAN
#define SHORT(x)  ((signed short) (x))
#define LONG(x)   ((signed int) (x))
#elif ( __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ )
#define SYS_BIG_ENDIAN
 
static inline unsigned short swapLE16(unsigned short val) {
    return ((val << 8) | (val >> 8));
}
 
static inline unsigned long swapLE32(unsigned long val) {
    return ((val << 24) | ((val << 8) & 0x00FF0000) | ((val >> 8) & 0x0000FF00) | (val >> 24));
}
 
#define SHORT(x)  ((signed short) swapLE16(x))
#define LONG(x)   ((signed int) swapLE32(x))
#else
#error "Unknown byte order"
#endif
 
 
// cosmito from lsdldoom
#define doom_swap_s(x) \
        ((short int)((((unsigned short int)(x) & 0x00ff) << 8) | \
                              (((unsigned short int)(x) & 0xff00) >> 8))) 
 
#if ( __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ )
#define doom_wtohs(x) doom_swap_s(x)
#else
#define doom_wtohs(x) (short int)(x)
#endif
 
 
#endif  // __DJGPP__
 
 
#endif