114 lines
4.6 KiB
C++
114 lines
4.6 KiB
C++
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/*
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** Command & Conquer Red Alert(tm)
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** Copyright 2025 Electronic Arts Inc.
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**
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** This program is free software: you can redistribute it and/or modify
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** it under the terms of the GNU General Public License as published by
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** the Free Software Foundation, either version 3 of the License, or
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** (at your option) any later version.
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**
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** This program is distributed in the hope that it will be useful,
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** but WITHOUT ANY WARRANTY; without even the implied warranty of
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** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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** GNU General Public License for more details.
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**
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** You should have received a copy of the GNU General Public License
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** along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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/***************************************************************************
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** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S **
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***************************************************************************
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* *
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* Project Name : Descriptor management *
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* *
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* File Name : DESCMGMT.CPP *
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* *
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* Programmer : Jeff Wilson *
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* *
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* Start Date : March 28, 1994 *
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* *
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* Last Update : March 28, 1994 [] *
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* *
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*-------------------------------------------------------------------------*
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* Functions: *
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* MAP_SEGMENT_TO_ADDRESS -- Maps a physical address into a selector *
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* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
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#include "descmgmt.h"
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#include "misc.h"
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/***************************************************************************
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* MAP_SEGMENT_TO_ADDRESS -- Maps a physical address into a selector *
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* *
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* *
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* *
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* INPUT: *
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* *
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* OUTPUT: selector UWORD The selector mapped to address. exit on error. *
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* *
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* WARNINGS: *
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* *
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* HISTORY: *
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* 03/25/1994 jaw: Created. *
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*=========================================================================*/
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ULONG Map_Segment_To_Address(ULONG address, ULONG length)
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{
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// this function is not longer needed by RATIONAL SYSTEM DOS4GW
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// linear addressing mode.
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// a> the first megabyte of memory is mapped to linear adress 0 - 0x10000h
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// b> all other addresses are linear offset from either ds: or es:
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/*
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UWORD segment;
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UWORD curDS;
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CD_DES desc;
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CD_DES cur_desc;
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// allocate a selector
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if(_dos_allocmem(0, &segment) != 0) {
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Exit(1, "Allocation of Descriptor.\n");
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}
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// get the data for this selector
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if(_dx_ldt_rd(segment, (UCHAR *)&desc) != 0) {
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Exit(1, "Reading Descriptor.\n");
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}
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// get the data for current data segment
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curDS = GetDs();
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if(_dx_ldt_rd(curDS, (UCHAR *)&cur_desc) != 0) {
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Exit(1, "Reading Descriptor.\n");
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}
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// set limit
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desc.limit0_15 = (USHORT)(length & 0xffff);
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desc.limit16_19 = ((UCHAR)(length >> 16L)) | DOS_32;
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// set base address
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desc.base0_15 = (USHORT)(address & 0xffff);
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desc.base16_23 = (UCHAR)((address >> 16) & 0xff);
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desc.base24_31 = (UCHAR)((address >> 24) & 0xff);
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// set rights mark as icurrent data segment
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desc.arights = cur_desc.arights;
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// write to LDT selector
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if(_dx_ldt_wr(segment, (UCHAR *)&desc) != 0) {
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Exit(1, "Failed writing descriptor.\n");
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}
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// return selector number
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return segment;
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*/
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if ( address & 0xfff0ffff )
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Exit ( 1 , "Error mapping real address to lineal address.\n" ) ;
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return address ;
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}
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