sdl_byteorder.h

jpeg and mpeg 编解码技术源代码

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library 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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    [e-mail]
*/

#ifdef SAVE_RCSID
static char rcsid =
 "@(#) $Id: SDL_byteorder.h,v 1.4 2002/04/22 21:38:01 wmay Exp $";
#endif

/* Macros for determining the byte-order of this platform */

#ifndef _SDL_byteorder_h
#define _SDL_byteorder_h

/* The two types of endianness */
#define SDL_LIL_ENDIAN	1234
#define SDL_BIG_ENDIAN	4321

/* Pardon the mess, I'm trying to determine the endianness of this host.
   I'm doing it by preprocessor defines rather than some sort of configure
   script so that application code can use this too.  The "right" way would
   be to dynamically generate this file on install, but that's a lot of work.
 */
#if  defined(__i386__) || defined(__ia64__) || defined(WIN32) || \
    (defined(__alpha__) || defined(__alpha)) || \
     defined(__arm__) || \
    (defined(__mips__) && defined(__MIPSEL__)) || \
     defined(__SYMBIAN32__) || \
     defined(__LITTLE_ENDIAN__)
#define SDL_BYTEORDER	SDL_LIL_ENDIAN
#else
#define SDL_BYTEORDER	SDL_BIG_ENDIAN
#endif

#endif /* _SDL_byteorder_h */