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672 lines
20 KiB
C
672 lines
20 KiB
C
/*
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* DOS memory emulation
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*
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* Copyright 1995 Alexandre Julliard
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* Copyright 1996 Marcus Meissner
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library 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 GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
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*/
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#include "config.h"
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#include "wine/port.h"
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#include <signal.h>
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#include <stdarg.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/types.h>
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#ifdef HAVE_SYS_MMAN_H
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# include <sys/mman.h>
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#endif
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#include "windef.h"
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#include "winbase.h"
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#include "excpt.h"
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#include "winternl.h"
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#include "wine/winbase16.h"
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#include "kernel16_private.h"
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#include "dosexe.h"
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#include "wine/debug.h"
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WINE_DEFAULT_DEBUG_CHANNEL(dosmem);
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WINE_DECLARE_DEBUG_CHANNEL(selector);
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WORD DOSMEM_0000H; /* segment at 0:0 */
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WORD DOSMEM_BiosDataSeg; /* BIOS data segment at 0x40:0 */
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WORD DOSMEM_BiosSysSeg; /* BIOS ROM segment at 0xf000:0 */
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/* DOS memory highest address (including HMA) */
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#define DOSMEM_SIZE 0x110000
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#define DOSMEM_64KB 0x10000
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/*
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* Memory Control Block (MCB) definition
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* FIXME: implement Allocation Strategy
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*/
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#define MCB_DUMP(mc) \
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TRACE ("MCB_DUMP base=%p type=%02xh psp=%04xh size=%04xh\n", mc, mc->type, mc->psp , mc->size )
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#define MCB_NEXT(mc) \
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(MCB*) ((mc->type==MCB_TYPE_LAST) ? NULL : (char*)(mc) + ((mc->size + 1) << 4) )
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/* FIXME: should we check more? */
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#define MCB_VALID(mc) \
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((mc->type==MCB_TYPE_NORMAL) || (mc->type==MCB_TYPE_LAST))
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#define MCB_TYPE_NORMAL 0x4d
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#define MCB_TYPE_LAST 0x5a
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#define MCB_PSP_DOS 0x0060
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#define MCB_PSP_FREE 0
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#include "pshpack1.h"
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typedef struct {
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BYTE type;
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WORD psp; /* segment of owner psp */
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WORD size; /* in paragraphs */
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BYTE pad[3];
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BYTE name[8];
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} MCB;
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#include "poppack.h"
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/*
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#define __DOSMEM_DEBUG__
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*/
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#define VM_STUB(x) (0x90CF00CD|(x<<8)) /* INT x; IRET; NOP */
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#define VM_STUB_SEGMENT 0xf000 /* BIOS segment */
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/* FIXME: this should be moved to the LOL */
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static MCB* DOSMEM_root_block;
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/* when looking at DOS and real mode memory, we activate in three different
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* modes, depending the situation.
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* 1/ By default (protected mode), the first MB of memory (actually 0x110000,
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* when you also look at the HMA part) is always reserved, whatever you do.
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* We allocated some PM selectors to this memory, even if this area is not
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* committed at startup
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* 2/ if a program tries to use the memory through the selectors, we actually
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* commit this memory, made of: BIOS segment, but also some system
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* information, usually low in memory that we map for the circumstance also
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* in the BIOS segment, so that we keep the low memory protected (for NULL
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* pointer deref catching for example). In this case, we're still in PM
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* mode, accessing part of the "physical" real mode memory. In fact, we don't
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* map all the first meg, we keep 64k uncommitted to still catch NULL
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* pointers dereference
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* 3/ if the process enters the real mode, then we (also) commit the full first
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* MB of memory (and also initialize the DOS structures in it).
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*/
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/* DOS memory base (linear in process address space) */
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static char *DOSMEM_dosmem;
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static char *DOSMEM_sysmem;
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/* number of bytes protected from _dosmem. 0 when DOS memory is initialized,
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* 64k otherwise to trap NULL pointers deref */
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static DWORD DOSMEM_protect;
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static LONG WINAPI dosmem_handler(EXCEPTION_POINTERS* except);
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static void *vectored_handler;
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/***********************************************************************
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* DOSMEM_FillIsrTable
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*
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* Fill the interrupt table with fake BIOS calls to BIOSSEG (0xf000).
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*
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* NOTES:
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* Linux normally only traps INTs performed from or destined to BIOSSEG
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* for us to handle, if the int_revectored table is empty. Filling the
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* interrupt table with calls to INT stubs in BIOSSEG allows DOS programs
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* to hook interrupts, as well as use their familiar retf tricks to call
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* them, AND let Wine handle any unhooked interrupts transparently.
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*/
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static void DOSMEM_FillIsrTable(void)
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{
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SEGPTR *isr = (SEGPTR*)DOSMEM_sysmem;
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int x;
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for (x=0; x<256; x++) isr[x]=MAKESEGPTR(VM_STUB_SEGMENT,x*4);
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}
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static void DOSMEM_MakeIsrStubs(void)
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{
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DWORD *stub = (DWORD*)(DOSMEM_dosmem + (VM_STUB_SEGMENT << 4));
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int x;
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for (x=0; x<256; x++) stub[x]=VM_STUB(x);
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}
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BIOSDATA* DOSVM_BiosData(void)
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{
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return (BIOSDATA *)(DOSMEM_sysmem + 0x400);
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}
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/**********************************************************************
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* DOSMEM_GetTicksSinceMidnight
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*
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* Return number of clock ticks since midnight.
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*/
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static DWORD DOSMEM_GetTicksSinceMidnight(void)
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{
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SYSTEMTIME time;
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/* This should give us the (approximately) correct
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* 18.206 clock ticks per second since midnight.
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*/
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GetLocalTime( &time );
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return (((time.wHour * 3600 + time.wMinute * 60 +
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time.wSecond) * 18206) / 1000) +
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(time.wMilliseconds * 1000 / 54927);
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}
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/***********************************************************************
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* DOSMEM_FillBiosSegments
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*
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* Fill the BIOS data segment with dummy values.
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*/
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static void DOSMEM_FillBiosSegments(void)
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{
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BYTE *pBiosSys = (BYTE*)DOSMEM_dosmem + 0xf0000;
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BYTE *pBiosROMTable = pBiosSys+0xe6f5;
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BIOSDATA *pBiosData = DOSVM_BiosData();
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static const char bios_date[] = "13/01/99";
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/* Clear all unused values */
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memset( pBiosData, 0, sizeof(*pBiosData) );
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/* FIXME: should check the number of configured drives and ports */
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pBiosData->Com1Addr = 0x3f8;
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pBiosData->Com2Addr = 0x2f8;
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pBiosData->Lpt1Addr = 0x378;
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pBiosData->Lpt2Addr = 0x278;
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pBiosData->InstalledHardware = 0x5463;
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pBiosData->MemSize = 640;
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pBiosData->NextKbdCharPtr = 0x1e;
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pBiosData->FirstKbdCharPtr = 0x1e;
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pBiosData->VideoMode = 3;
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pBiosData->VideoColumns = 80;
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pBiosData->VideoPageSize = 80 * 25 * 2;
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pBiosData->VideoPageStartAddr = 0xb800;
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pBiosData->VideoCtrlAddr = 0x3d4;
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pBiosData->Ticks = DOSMEM_GetTicksSinceMidnight();
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pBiosData->NbHardDisks = 2;
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pBiosData->KbdBufferStart = 0x1e;
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pBiosData->KbdBufferEnd = 0x3e;
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pBiosData->RowsOnScreenMinus1 = 24;
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pBiosData->BytesPerChar = 0x10;
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pBiosData->ModeOptions = 0x64;
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pBiosData->FeatureBitsSwitches = 0xf9;
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pBiosData->VGASettings = 0x51;
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pBiosData->DisplayCombination = 0x08;
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pBiosData->DiskDataRate = 0;
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/* fill ROM configuration table (values from Award) */
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*(pBiosROMTable+0x0) = 0x08; /* number of bytes following LO */
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*(pBiosROMTable+0x1) = 0x00; /* number of bytes following HI */
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*(pBiosROMTable+0x2) = 0xfc; /* model */
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*(pBiosROMTable+0x3) = 0x01; /* submodel */
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*(pBiosROMTable+0x4) = 0x00; /* BIOS revision */
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*(pBiosROMTable+0x5) = 0x74; /* feature byte 1 */
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*(pBiosROMTable+0x6) = 0x00; /* feature byte 2 */
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*(pBiosROMTable+0x7) = 0x00; /* feature byte 3 */
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*(pBiosROMTable+0x8) = 0x00; /* feature byte 4 */
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*(pBiosROMTable+0x9) = 0x00; /* feature byte 5 */
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/* BIOS date string */
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memcpy(pBiosSys+0xfff5, bios_date, sizeof bios_date);
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/* BIOS ID */
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*(pBiosSys+0xfffe) = 0xfc;
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/* Reboot vector (f000:fff0 or ffff:0000) */
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*(DWORD*)(pBiosSys + 0xfff0) = VM_STUB(0x19);
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}
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/***********************************************************************
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* BiosTick
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*
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* Increment the BIOS tick counter. Called by timer signal handler.
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*/
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static void CALLBACK BiosTick( LPVOID arg, DWORD low, DWORD high )
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{
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BIOSDATA *pBiosData = arg;
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pBiosData->Ticks++;
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}
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/***********************************************************************
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* timer_thread
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*/
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static DWORD CALLBACK timer_thread( void *arg )
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{
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LARGE_INTEGER when;
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HANDLE timer;
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if (!(timer = CreateWaitableTimerA( NULL, FALSE, NULL ))) return 0;
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when.u.LowPart = when.u.HighPart = 0;
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SetWaitableTimer( timer, &when, 55 /* actually 54.925 */, BiosTick, arg, FALSE );
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for (;;) SleepEx( INFINITE, TRUE );
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}
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/***********************************************************************
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* DOSVM_start_bios_timer
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*
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* Start the BIOS ticks timer when the app accesses selector 0x40.
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*/
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void DOSVM_start_bios_timer(void)
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{
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static LONG running;
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if (!InterlockedExchange( &running, 1 ))
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CloseHandle( CreateThread( NULL, 0, timer_thread, DOSVM_BiosData(), 0, NULL ));
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}
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/***********************************************************************
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* DOSMEM_Collapse
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*
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* Helper function for internal use only.
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* Attach all following free blocks to this one, even if this one is not free.
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*/
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static void DOSMEM_Collapse( MCB* mcb )
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{
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MCB* next = MCB_NEXT( mcb );
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while (next && next->psp == MCB_PSP_FREE)
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{
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mcb->size = mcb->size + next->size + 1;
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mcb->type = next->type; /* make sure keeping MCB_TYPE_LAST */
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next = MCB_NEXT( next );
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}
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}
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/******************************************************************
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* DOSMEM_InitDosMemory
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*/
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BOOL DOSMEM_InitDosMemory(void)
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{
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static int done;
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static HANDLE hRunOnce;
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if (done) return TRUE;
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/* FIXME: this isn't 100% thread safe, as we won't catch accesses while initializing */
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if (hRunOnce == 0)
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{
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HANDLE hEvent = CreateEventW( NULL, TRUE, FALSE, NULL );
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if (InterlockedCompareExchangePointer( &hRunOnce, hEvent, 0 ) == 0)
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{
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BOOL ret;
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DWORD reserve;
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/* ok, we're the winning thread */
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if (!(ret = VirtualProtect( DOSMEM_dosmem + DOSMEM_protect,
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DOSMEM_SIZE - DOSMEM_protect,
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PAGE_READWRITE, NULL )))
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ERR("Cannot load access low 1Mb, DOS subsystem unavailable\n");
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RemoveVectoredExceptionHandler( vectored_handler );
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/*
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* Reserve either:
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* - lowest 64k for NULL pointer catching (Win16)
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* - lowest 1k for interrupt handlers and
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* another 0.5k for BIOS, DOS and intra-application
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* areas (DOS)
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*/
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if (DOSMEM_dosmem != DOSMEM_sysmem)
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reserve = 0x10000; /* 64k */
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else
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reserve = 0x600; /* 1.5k */
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/*
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* Set DOS memory base and initialize conventional memory.
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*/
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DOSMEM_FillBiosSegments();
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DOSMEM_FillIsrTable();
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/* align root block to paragraph */
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DOSMEM_root_block = (MCB*)(DOSMEM_dosmem + reserve);
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DOSMEM_root_block->type = MCB_TYPE_LAST;
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DOSMEM_root_block->psp = MCB_PSP_FREE;
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DOSMEM_root_block->size = (DOSMEM_dosmem + 0x9fffc - ((char*)DOSMEM_root_block)) >> 4;
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TRACE("DOS conventional memory initialized, %d bytes free.\n",
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DOSMEM_Available());
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DOSVM_InitSegments();
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SetEvent( hRunOnce );
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done = 1;
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return ret;
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}
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/* someone beat us here... */
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CloseHandle( hEvent );
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}
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/* and wait for the winner to have finished */
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WaitForSingleObject( hRunOnce, INFINITE );
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return TRUE;
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}
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/******************************************************************
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* dosmem_handler
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*
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* Handler to catch access to our 1MB address space reserved for real memory
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*/
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static LONG WINAPI dosmem_handler(EXCEPTION_POINTERS* except)
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{
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if (except->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
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{
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char *addr = (char *)except->ExceptionRecord->ExceptionInformation[1];
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if (addr >= DOSMEM_dosmem + DOSMEM_protect && addr < DOSMEM_dosmem + DOSMEM_SIZE)
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{
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if (DOSMEM_InitDosMemory()) return EXCEPTION_CONTINUE_EXECUTION;
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}
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}
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return EXCEPTION_CONTINUE_SEARCH;
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}
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/***********************************************************************
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* DOSMEM_Init
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*
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* Create the dos memory segments, and store them into the KERNEL
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* exported values.
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*/
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BOOL DOSMEM_Init(void)
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{
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void *addr = (void *)1;
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SIZE_T size = DOSMEM_SIZE - 1;
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if (NtAllocateVirtualMemory( GetCurrentProcess(), &addr, 0, &size,
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MEM_RESERVE | MEM_COMMIT, PAGE_NOACCESS ))
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{
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ERR( "Cannot allocate DOS memory\n" );
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ExitProcess(1);
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}
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if (addr <= (void *)DOSMEM_64KB)
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{
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DOSMEM_dosmem = 0;
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DOSMEM_protect = DOSMEM_64KB;
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DOSMEM_sysmem = (char *)0xf0000; /* store sysmem in high addresses for now */
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}
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else
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{
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WARN( "First megabyte not available for DOS address space.\n" );
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DOSMEM_dosmem = addr;
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DOSMEM_protect = 0;
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DOSMEM_sysmem = DOSMEM_dosmem;
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}
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vectored_handler = AddVectoredExceptionHandler(FALSE, dosmem_handler);
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DOSMEM_0000H = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem,
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DOSMEM_64KB, 0, WINE_LDT_FLAGS_DATA );
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DOSMEM_BiosDataSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem + 0x400,
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0x100, 0, WINE_LDT_FLAGS_DATA );
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DOSMEM_BiosSysSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_dosmem + 0xf0000,
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DOSMEM_64KB, 0, WINE_LDT_FLAGS_DATA );
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return TRUE;
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}
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/***********************************************************************
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* DOSMEM_MapLinearToDos
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*
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* Linear address to the DOS address space.
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*/
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UINT DOSMEM_MapLinearToDos(LPVOID ptr)
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{
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if (((char*)ptr >= DOSMEM_dosmem) &&
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((char*)ptr < DOSMEM_dosmem + DOSMEM_SIZE))
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return (char *)ptr - DOSMEM_dosmem;
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return (UINT)ptr;
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}
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/***********************************************************************
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* DOSMEM_MapDosToLinear
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*
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* DOS linear address to the linear address space.
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*/
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LPVOID DOSMEM_MapDosToLinear(UINT ptr)
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{
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if (ptr < DOSMEM_SIZE) return DOSMEM_dosmem + ptr;
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return (LPVOID)ptr;
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}
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/***********************************************************************
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* DOSMEM_MapRealToLinear
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*
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* Real mode DOS address into a linear pointer
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*/
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LPVOID DOSMEM_MapRealToLinear(DWORD x)
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{
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LPVOID lin;
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lin = DOSMEM_dosmem + HIWORD(x) * 16 + LOWORD(x);
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TRACE_(selector)("(0x%08x) returns %p.\n", x, lin );
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return lin;
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}
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/***********************************************************************
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* DOSMEM_AllocBlock
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*
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* Carve a chunk of the DOS memory block (without selector).
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*/
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LPVOID DOSMEM_AllocBlock(UINT size, UINT16* pseg)
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{
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MCB *curr;
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MCB *next = NULL;
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WORD psp;
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DOSMEM_InitDosMemory();
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curr = DOSMEM_root_block;
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if (!(psp = DOSVM_psp)) psp = MCB_PSP_DOS;
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if (pseg) *pseg = 0;
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TRACE( "(%04xh)\n", size );
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/* round up to paragraph */
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size = (size + 15) >> 4;
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#ifdef __DOSMEM_DEBUG__
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DOSMEM_Available(); /* checks the whole MCB list */
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#endif
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/* loop over all MCB and search the next large enough MCB */
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while (curr)
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{
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if (!MCB_VALID (curr))
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{
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ERR( "MCB List Corrupt\n" );
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MCB_DUMP( curr );
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return NULL;
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}
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if (curr->psp == MCB_PSP_FREE)
|
|
{
|
|
DOSMEM_Collapse( curr );
|
|
/* is it large enough (one paragraph for the MCB)? */
|
|
if (curr->size >= size)
|
|
{
|
|
if (curr->size > size)
|
|
{
|
|
/* split curr */
|
|
next = (MCB *) ((char*) curr + ((size+1) << 4));
|
|
next->psp = MCB_PSP_FREE;
|
|
next->size = curr->size - (size+1);
|
|
next->type = curr->type;
|
|
curr->type = MCB_TYPE_NORMAL;
|
|
curr->size = size;
|
|
}
|
|
/* curr is the found block */
|
|
curr->psp = psp;
|
|
if( pseg ) *pseg = (((char*)curr) + 16 - DOSMEM_dosmem) >> 4;
|
|
return (LPVOID) ((char*)curr + 16);
|
|
}
|
|
}
|
|
curr = MCB_NEXT(curr);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_FreeBlock
|
|
*/
|
|
BOOL DOSMEM_FreeBlock(void* ptr)
|
|
{
|
|
MCB* mcb = (MCB*) ((char*)ptr - 16);
|
|
|
|
TRACE( "(%p)\n", ptr );
|
|
|
|
#ifdef __DOSMEM_DEBUG__
|
|
DOSMEM_Available();
|
|
#endif
|
|
|
|
if (!MCB_VALID (mcb))
|
|
{
|
|
ERR( "MCB invalid\n" );
|
|
MCB_DUMP( mcb );
|
|
return FALSE;
|
|
}
|
|
|
|
mcb->psp = MCB_PSP_FREE;
|
|
DOSMEM_Collapse( mcb );
|
|
return TRUE;
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_ResizeBlock
|
|
*
|
|
* Resize DOS memory block in place. Returns block size or -1 on error.
|
|
*
|
|
* If exact is TRUE, returned value is either old or requested block
|
|
* size. If exact is FALSE, block is expanded even if there is not
|
|
* enough space for full requested block size.
|
|
*
|
|
* TODO: return also biggest block size
|
|
*/
|
|
UINT DOSMEM_ResizeBlock(void *ptr, UINT size, BOOL exact)
|
|
{
|
|
MCB* mcb = (MCB*) ((char*)ptr - 16);
|
|
MCB* next;
|
|
|
|
TRACE( "(%p,%04xh,%s)\n", ptr, size, exact ? "TRUE" : "FALSE" );
|
|
|
|
/* round up to paragraph */
|
|
size = (size + 15) >> 4;
|
|
|
|
#ifdef __DOSMEM_DEBUG__
|
|
DOSMEM_Available();
|
|
#endif
|
|
|
|
if (!MCB_VALID (mcb))
|
|
{
|
|
ERR( "MCB invalid\n" );
|
|
MCB_DUMP( mcb );
|
|
return -1;
|
|
}
|
|
|
|
/* resize needed? */
|
|
if (mcb->size == size)
|
|
return size << 4;
|
|
|
|
/* collapse free blocks */
|
|
DOSMEM_Collapse( mcb );
|
|
|
|
/* shrink mcb ? */
|
|
if (mcb->size > size)
|
|
{
|
|
next = (MCB *) ((char*)mcb + ((size+1) << 4));
|
|
next->type = mcb->type;
|
|
next->psp = MCB_PSP_FREE;
|
|
next->size = mcb->size - (size+1);
|
|
mcb->type = MCB_TYPE_NORMAL;
|
|
mcb->size = size;
|
|
return size << 4;
|
|
}
|
|
|
|
if (!exact)
|
|
{
|
|
return mcb->size << 4;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_Available
|
|
*/
|
|
UINT DOSMEM_Available(void)
|
|
{
|
|
UINT available = 0;
|
|
UINT total = 0;
|
|
MCB *curr = DOSMEM_root_block;
|
|
/* loop over all MCB and search the largest free MCB */
|
|
while (curr)
|
|
{
|
|
#ifdef __DOSMEM_DEBUG__
|
|
MCB_DUMP( curr );
|
|
#endif
|
|
if (!MCB_VALID (curr))
|
|
{
|
|
ERR( "MCB List Corrupt\n" );
|
|
MCB_DUMP( curr );
|
|
return 0;
|
|
}
|
|
if (curr->psp == MCB_PSP_FREE &&
|
|
curr->size > available )
|
|
available = curr->size;
|
|
|
|
total += curr->size + 1;
|
|
curr = MCB_NEXT( curr );
|
|
}
|
|
TRACE( " %04xh of %04xh paragraphs available\n", available, total );
|
|
return available << 4;
|
|
}
|
|
|
|
/******************************************************************
|
|
* DOSMEM_MapDosLayout
|
|
*
|
|
* Initialize the first MB of memory to look like a real DOS setup
|
|
*/
|
|
BOOL DOSMEM_MapDosLayout(void)
|
|
{
|
|
static int already_mapped;
|
|
|
|
if (!already_mapped)
|
|
{
|
|
if (DOSMEM_dosmem || !VirtualProtect( NULL, DOSMEM_SIZE, PAGE_EXECUTE_READWRITE, NULL ))
|
|
{
|
|
ERR( "Need full access to the first megabyte for DOS mode\n" );
|
|
ExitProcess(1);
|
|
}
|
|
/* copy the BIOS and ISR area down */
|
|
memcpy( DOSMEM_dosmem, DOSMEM_sysmem, 0x400 + 0x100 );
|
|
DOSMEM_sysmem = DOSMEM_dosmem;
|
|
SetSelectorBase( DOSMEM_0000H, 0 );
|
|
SetSelectorBase( DOSMEM_BiosDataSeg, 0x400 );
|
|
/* we may now need the actual interrupt stubs, and since we've just moved the
|
|
* interrupt vector table away, we can fill the area with stubs instead... */
|
|
DOSMEM_MakeIsrStubs();
|
|
already_mapped = 1;
|
|
}
|
|
return TRUE;
|
|
}
|