n_mem.c

开放源码的编译器open watcom 1.6.0版的源代码

/****************************************************************************
*
*                            Open Watcom Project
*
*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
*  ========================================================================
*
*    This file contains Original Code and/or Modifications of Original
*    Code as defined in and that are subject to the Sybase Open Watcom
*    Public License version 1.0 (the 'License'). You may not use this file
*    except in compliance with the License. BY USING THIS FILE YOU AGREE TO
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*    provided with the Original Code and Modifications, and is also
*    available at www.sybase.com/developer/opensource.
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* Description:  WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
*               DESCRIBE IT HERE!
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****************************************************************************/


#include "variety.h"
#include <bios98.h>
#include <dos.h>
#include "nonibm.h"

#ifdef __386__
#include "extender.h"
#endif

_WCRTLINK unsigned short __nec98_bios_memsize( void )
{
    int __data = 0;

    if( !__NonIBM )  return( 0 );       // fail if not a NEC 98 machine

#ifdef __386__
    if( _ExtenderRealModeSelector ){
        __data = *(unsigned char _WCFAR *)
                MK_FP( _ExtenderRealModeSelector, 0xa3fea );
    }
#else
    __data = *(unsigned char _WCFAR *)MK_FP(0xa000, 0x3fea);
#endif
    return( ( ( __data & 0x07 ) + 1 ) * 0x80 );
}