mapa2f.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 57 行

/****************************************************************************
*
*                            Open Watcom Project
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*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
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*  ========================================================================
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*    This file contains Original Code and/or Modifications of Original
*    Code as defined in and that are subject to the Sybase Open Watcom
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* Description:  WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
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****************************************************************************/


#include <string.h>
#include <dos.h>
#include "alloc.h"

void *MapAliasToFlat( DWORD alias )
{
    union REGPACK       r;
    DWORD               base_32;
    DWORD               base_16;
    DWORD               res;

    memset( &r, 0, sizeof( r ) );
    r.x.ax = 0x06;
    r.x.bx = FP_SEG( (void far *) &r );
    intr( 0x31, &r );
    base_32 = (r.x.cx << 16L) + (DWORD) r.x.dx;
    r.x.ax = 0x06;
    r.x.bx = alias >> 16;
    intr( 0x31, &r );
    base_16 = (r.x.cx << 16L) + (DWORD) r.x.dx;
    res = base_16 - base_32 + (DWORD)((WORD)alias);
    return( (void *) res );

} /* MapAliasToFlat */