725 lines
22 KiB
C
725 lines
22 KiB
C
/*
|
|
* DOS memory emulation
|
|
*
|
|
* Copyright 1995 Alexandre Julliard
|
|
* Copyright 1996 Marcus Meissner
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 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
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
|
|
*/
|
|
|
|
#include <signal.h>
|
|
#include <stdarg.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <sys/types.h>
|
|
|
|
#include "windef.h"
|
|
#include "winbase.h"
|
|
#include "excpt.h"
|
|
#include "winternl.h"
|
|
#include "wine/winbase16.h"
|
|
|
|
#include "kernel16_private.h"
|
|
#include "dosexe.h"
|
|
#include "wine/debug.h"
|
|
|
|
WINE_DEFAULT_DEBUG_CHANNEL(dosmem);
|
|
WINE_DECLARE_DEBUG_CHANNEL(selector);
|
|
|
|
WORD DOSMEM_0000H; /* segment at 0:0 */
|
|
WORD DOSMEM_BiosDataSeg; /* BIOS data segment at 0x40:0 */
|
|
WORD DOSMEM_BiosSysSeg; /* BIOS ROM segment at 0xf000:0 */
|
|
|
|
WORD DOSVM_psp = 0;
|
|
WORD int16_sel = 0;
|
|
WORD relay_code_sel = 0;
|
|
WORD relay_data_sel = 0;
|
|
|
|
/* DOS memory highest address (including HMA) */
|
|
#define DOSMEM_SIZE 0x110000
|
|
#define DOSMEM_64KB 0x10000
|
|
|
|
/*
|
|
* Memory Control Block (MCB) definition
|
|
* FIXME: implement Allocation Strategy
|
|
*/
|
|
|
|
#define MCB_DUMP(mc) \
|
|
TRACE ("MCB_DUMP base=%p type=%02xh psp=%04xh size=%04xh\n", mc, mc->type, mc->psp , mc->size )
|
|
|
|
#define MCB_NEXT(mc) \
|
|
(MCB*) ((mc->type==MCB_TYPE_LAST) ? NULL : (char*)(mc) + ((mc->size + 1) << 4) )
|
|
|
|
/* FIXME: should we check more? */
|
|
#define MCB_VALID(mc) \
|
|
((mc->type==MCB_TYPE_NORMAL) || (mc->type==MCB_TYPE_LAST))
|
|
|
|
|
|
#define MCB_TYPE_NORMAL 0x4d
|
|
#define MCB_TYPE_LAST 0x5a
|
|
|
|
#define MCB_PSP_DOS 0x0060
|
|
#define MCB_PSP_FREE 0
|
|
|
|
#include "pshpack1.h"
|
|
typedef struct {
|
|
BYTE type;
|
|
WORD psp; /* segment of owner psp */
|
|
WORD size; /* in paragraphs */
|
|
BYTE pad[3];
|
|
BYTE name[8];
|
|
} MCB;
|
|
#include "poppack.h"
|
|
|
|
/*
|
|
#define __DOSMEM_DEBUG__
|
|
*/
|
|
|
|
#define VM_STUB(x) (0x90CF00CD|(x<<8)) /* INT x; IRET; NOP */
|
|
#define VM_STUB_SEGMENT 0xf000 /* BIOS segment */
|
|
|
|
/* FIXME: this should be moved to the LOL */
|
|
static MCB* DOSMEM_root_block;
|
|
|
|
/* when looking at DOS and real mode memory, we activate in three different
|
|
* modes, depending the situation.
|
|
* 1/ By default (protected mode), the first MB of memory (actually 0x110000,
|
|
* when you also look at the HMA part) is always reserved, whatever you do.
|
|
* We allocated some PM selectors to this memory, even if this area is not
|
|
* committed at startup
|
|
* 2/ if a program tries to use the memory through the selectors, we actually
|
|
* commit this memory, made of: BIOS segment, but also some system
|
|
* information, usually low in memory that we map for the circumstance also
|
|
* in the BIOS segment, so that we keep the low memory protected (for NULL
|
|
* pointer deref catching for example). In this case, we're still in PM
|
|
* mode, accessing part of the "physical" real mode memory. In fact, we don't
|
|
* map all the first meg, we keep 64k uncommitted to still catch NULL
|
|
* pointers dereference
|
|
* 3/ if the process enters the real mode, then we (also) commit the full first
|
|
* MB of memory (and also initialize the DOS structures in it).
|
|
*/
|
|
|
|
/* DOS memory base (linear in process address space) */
|
|
static char *DOSMEM_dosmem;
|
|
static char *DOSMEM_sysmem;
|
|
/* number of bytes protected from _dosmem. 0 when DOS memory is initialized,
|
|
* 64k otherwise to trap NULL pointers deref */
|
|
static DWORD DOSMEM_protect;
|
|
|
|
static LONG WINAPI dosmem_handler(EXCEPTION_POINTERS* except);
|
|
static void *vectored_handler;
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_FillIsrTable
|
|
*
|
|
* Fill the interrupt table with fake BIOS calls to BIOSSEG (0xf000).
|
|
*
|
|
* NOTES:
|
|
* Linux normally only traps INTs performed from or destined to BIOSSEG
|
|
* for us to handle, if the int_revectored table is empty. Filling the
|
|
* interrupt table with calls to INT stubs in BIOSSEG allows DOS programs
|
|
* to hook interrupts, as well as use their familiar retf tricks to call
|
|
* them, AND let Wine handle any unhooked interrupts transparently.
|
|
*/
|
|
static void DOSMEM_FillIsrTable(void)
|
|
{
|
|
SEGPTR *isr = (SEGPTR*)DOSMEM_sysmem;
|
|
int x;
|
|
|
|
for (x=0; x<256; x++) isr[x]=MAKESEGPTR(VM_STUB_SEGMENT,x*4);
|
|
}
|
|
|
|
static void DOSMEM_MakeIsrStubs(void)
|
|
{
|
|
DWORD *stub = (DWORD*)(DOSMEM_dosmem + (VM_STUB_SEGMENT << 4));
|
|
int x;
|
|
|
|
for (x=0; x<256; x++) stub[x]=VM_STUB(x);
|
|
}
|
|
|
|
BIOSDATA* DOSVM_BiosData(void)
|
|
{
|
|
return (BIOSDATA *)(DOSMEM_sysmem + 0x400);
|
|
}
|
|
|
|
/**********************************************************************
|
|
* DOSMEM_GetTicksSinceMidnight
|
|
*
|
|
* Return number of clock ticks since midnight.
|
|
*/
|
|
static DWORD DOSMEM_GetTicksSinceMidnight(void)
|
|
{
|
|
SYSTEMTIME time;
|
|
|
|
/* This should give us the (approximately) correct
|
|
* 18.206 clock ticks per second since midnight.
|
|
*/
|
|
|
|
GetLocalTime( &time );
|
|
|
|
return (((time.wHour * 3600 + time.wMinute * 60 +
|
|
time.wSecond) * 18206) / 1000) +
|
|
(time.wMilliseconds * 1000 / 54927);
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_FillBiosSegments
|
|
*
|
|
* Fill the BIOS data segment with dummy values.
|
|
*/
|
|
static void DOSMEM_FillBiosSegments(void)
|
|
{
|
|
BYTE *pBiosSys = (BYTE*)DOSMEM_dosmem + 0xf0000;
|
|
BYTE *pBiosROMTable = pBiosSys+0xe6f5;
|
|
BIOSDATA *pBiosData = DOSVM_BiosData();
|
|
static const char bios_date[] = "13/01/99";
|
|
|
|
/* Clear all unused values */
|
|
memset( pBiosData, 0, sizeof(*pBiosData) );
|
|
|
|
/* FIXME: should check the number of configured drives and ports */
|
|
pBiosData->Com1Addr = 0x3f8;
|
|
pBiosData->Com2Addr = 0x2f8;
|
|
pBiosData->Lpt1Addr = 0x378;
|
|
pBiosData->Lpt2Addr = 0x278;
|
|
pBiosData->InstalledHardware = 0x5463;
|
|
pBiosData->MemSize = 640;
|
|
pBiosData->NextKbdCharPtr = 0x1e;
|
|
pBiosData->FirstKbdCharPtr = 0x1e;
|
|
pBiosData->VideoMode = 3;
|
|
pBiosData->VideoColumns = 80;
|
|
pBiosData->VideoPageSize = 80 * 25 * 2;
|
|
pBiosData->VideoPageStartAddr = 0xb800;
|
|
pBiosData->VideoCtrlAddr = 0x3d4;
|
|
pBiosData->Ticks = DOSMEM_GetTicksSinceMidnight();
|
|
pBiosData->NbHardDisks = 2;
|
|
pBiosData->KbdBufferStart = 0x1e;
|
|
pBiosData->KbdBufferEnd = 0x3e;
|
|
pBiosData->RowsOnScreenMinus1 = 24;
|
|
pBiosData->BytesPerChar = 0x10;
|
|
pBiosData->ModeOptions = 0x64;
|
|
pBiosData->FeatureBitsSwitches = 0xf9;
|
|
pBiosData->VGASettings = 0x51;
|
|
pBiosData->DisplayCombination = 0x08;
|
|
pBiosData->DiskDataRate = 0;
|
|
|
|
/* fill ROM configuration table (values from Award) */
|
|
*(pBiosROMTable+0x0) = 0x08; /* number of bytes following LO */
|
|
*(pBiosROMTable+0x1) = 0x00; /* number of bytes following HI */
|
|
*(pBiosROMTable+0x2) = 0xfc; /* model */
|
|
*(pBiosROMTable+0x3) = 0x01; /* submodel */
|
|
*(pBiosROMTable+0x4) = 0x00; /* BIOS revision */
|
|
*(pBiosROMTable+0x5) = 0x74; /* feature byte 1 */
|
|
*(pBiosROMTable+0x6) = 0x00; /* feature byte 2 */
|
|
*(pBiosROMTable+0x7) = 0x00; /* feature byte 3 */
|
|
*(pBiosROMTable+0x8) = 0x00; /* feature byte 4 */
|
|
*(pBiosROMTable+0x9) = 0x00; /* feature byte 5 */
|
|
|
|
/* BIOS date string */
|
|
memcpy(pBiosSys+0xfff5, bios_date, sizeof bios_date);
|
|
|
|
/* BIOS ID */
|
|
*(pBiosSys+0xfffe) = 0xfc;
|
|
|
|
/* Reboot vector (f000:fff0 or ffff:0000) */
|
|
*(DWORD*)(pBiosSys + 0xfff0) = VM_STUB(0x19);
|
|
}
|
|
|
|
/***********************************************************************
|
|
* BiosTick
|
|
*
|
|
* Increment the BIOS tick counter. Called by timer signal handler.
|
|
*/
|
|
static void CALLBACK BiosTick( LPVOID arg, DWORD low, DWORD high )
|
|
{
|
|
BIOSDATA *pBiosData = arg;
|
|
pBiosData->Ticks++;
|
|
}
|
|
|
|
/***********************************************************************
|
|
* timer_thread
|
|
*/
|
|
static DWORD CALLBACK timer_thread( void *arg )
|
|
{
|
|
LARGE_INTEGER when;
|
|
HANDLE timer;
|
|
|
|
if (!(timer = CreateWaitableTimerA( NULL, FALSE, NULL ))) return 0;
|
|
|
|
when.u.LowPart = when.u.HighPart = 0;
|
|
SetWaitableTimer( timer, &when, 55 /* actually 54.925 */, BiosTick, arg, FALSE );
|
|
for (;;) SleepEx( INFINITE, TRUE );
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSVM_start_bios_timer
|
|
*
|
|
* Start the BIOS ticks timer when the app accesses selector 0x40.
|
|
*/
|
|
void DOSVM_start_bios_timer(void)
|
|
{
|
|
static LONG running;
|
|
|
|
if (!InterlockedExchange( &running, 1 ))
|
|
CloseHandle( CreateThread( NULL, 0, timer_thread, DOSVM_BiosData(), 0, NULL ));
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_Collapse
|
|
*
|
|
* Helper function for internal use only.
|
|
* Attach all following free blocks to this one, even if this one is not free.
|
|
*/
|
|
static void DOSMEM_Collapse( MCB* mcb )
|
|
{
|
|
MCB* next = MCB_NEXT( mcb );
|
|
|
|
while (next && next->psp == MCB_PSP_FREE)
|
|
{
|
|
mcb->size = mcb->size + next->size + 1;
|
|
mcb->type = next->type; /* make sure keeping MCB_TYPE_LAST */
|
|
next = MCB_NEXT( next );
|
|
}
|
|
}
|
|
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_InitSegments
|
|
*/
|
|
static void DOSMEM_InitSegments(void)
|
|
{
|
|
LPSTR ptr;
|
|
int i;
|
|
|
|
static const char relay[]=
|
|
{
|
|
0xca, 0x04, 0x00, /* 16-bit far return and pop 4 bytes (relay void* arg) */
|
|
0xcd, 0x31, /* int 31 */
|
|
0xfb, 0x66, 0xcb /* sti and 32-bit far return */
|
|
};
|
|
|
|
/*
|
|
* PM / offset N*5: Interrupt N in 16-bit protected mode.
|
|
*/
|
|
int16_sel = GLOBAL_Alloc( GMEM_FIXED, 5 * 256, 0, LDT_FLAGS_CODE );
|
|
ptr = GlobalLock16( int16_sel );
|
|
for(i=0; i<256; i++) {
|
|
/*
|
|
* Each 16-bit interrupt handler is 5 bytes:
|
|
* 0xCD,<i> = int <i> (interrupt)
|
|
* 0xCA,0x02,0x00 = ret 2 (16-bit far return and pop 2 bytes / eflags)
|
|
*/
|
|
ptr[i * 5 + 0] = 0xCD;
|
|
ptr[i * 5 + 1] = i;
|
|
ptr[i * 5 + 2] = 0xCA;
|
|
ptr[i * 5 + 3] = 0x02;
|
|
ptr[i * 5 + 4] = 0x00;
|
|
}
|
|
GlobalUnlock16( int16_sel );
|
|
|
|
/*
|
|
* PM / offset 0: Stub where __wine_call_from_16_regs returns.
|
|
* PM / offset 3: Stub which swaps back to 32-bit application code/stack.
|
|
* PM / offset 5: Stub which enables interrupts
|
|
*/
|
|
relay_code_sel = GLOBAL_Alloc( GMEM_FIXED, sizeof(relay), 0, LDT_FLAGS_CODE );
|
|
ptr = GlobalLock16( relay_code_sel );
|
|
memcpy( ptr, relay, sizeof(relay) );
|
|
GlobalUnlock16( relay_code_sel );
|
|
|
|
/*
|
|
* Space for 16-bit stack used by relay code.
|
|
*/
|
|
relay_data_sel = GlobalAlloc16( GMEM_FIXED | GMEM_ZEROINIT, DOSVM_RELAY_DATA_SIZE );
|
|
}
|
|
|
|
/******************************************************************
|
|
* DOSMEM_InitDosMemory
|
|
*/
|
|
BOOL DOSMEM_InitDosMemory(void)
|
|
{
|
|
static BOOL done;
|
|
static HANDLE hRunOnce;
|
|
DWORD old_prot;
|
|
|
|
if (done) return TRUE;
|
|
|
|
/* FIXME: this isn't 100% thread safe, as we won't catch accesses while initializing */
|
|
if (hRunOnce == 0)
|
|
{
|
|
HANDLE hEvent = CreateEventW( NULL, TRUE, FALSE, NULL );
|
|
if (InterlockedCompareExchangePointer( &hRunOnce, hEvent, 0 ) == 0)
|
|
{
|
|
BOOL ret;
|
|
DWORD reserve;
|
|
|
|
/* ok, we're the winning thread */
|
|
if (!(ret = VirtualProtect( DOSMEM_dosmem + DOSMEM_protect,
|
|
DOSMEM_SIZE - DOSMEM_protect,
|
|
PAGE_READWRITE, &old_prot )))
|
|
ERR("Cannot load access low 1Mb, DOS subsystem unavailable\n");
|
|
RemoveVectoredExceptionHandler( vectored_handler );
|
|
|
|
/*
|
|
* Reserve either:
|
|
* - lowest 64k for NULL pointer catching (Win16)
|
|
* - lowest 1k for interrupt handlers and
|
|
* another 0.5k for BIOS, DOS and intra-application
|
|
* areas (DOS)
|
|
*/
|
|
if (DOSMEM_dosmem != DOSMEM_sysmem)
|
|
reserve = 0x10000; /* 64k */
|
|
else
|
|
reserve = 0x600; /* 1.5k */
|
|
|
|
/*
|
|
* Set DOS memory base and initialize conventional memory.
|
|
*/
|
|
DOSMEM_FillBiosSegments();
|
|
DOSMEM_FillIsrTable();
|
|
|
|
/* align root block to paragraph */
|
|
DOSMEM_root_block = (MCB*)(DOSMEM_dosmem + reserve);
|
|
DOSMEM_root_block->type = MCB_TYPE_LAST;
|
|
DOSMEM_root_block->psp = MCB_PSP_FREE;
|
|
DOSMEM_root_block->size = (DOSMEM_dosmem + 0x9fffc - ((char*)DOSMEM_root_block)) >> 4;
|
|
|
|
TRACE("DOS conventional memory initialized, %d bytes free.\n",
|
|
DOSMEM_Available());
|
|
|
|
DOSMEM_InitSegments();
|
|
|
|
SetEvent( hRunOnce );
|
|
done = TRUE;
|
|
return ret;
|
|
}
|
|
/* someone beat us here... */
|
|
CloseHandle( hEvent );
|
|
}
|
|
|
|
/* and wait for the winner to have finished */
|
|
WaitForSingleObject( hRunOnce, INFINITE );
|
|
return TRUE;
|
|
}
|
|
|
|
/******************************************************************
|
|
* dosmem_handler
|
|
*
|
|
* Handler to catch access to our 1MB address space reserved for real memory
|
|
*/
|
|
static LONG WINAPI dosmem_handler(EXCEPTION_POINTERS* except)
|
|
{
|
|
if (except->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
|
|
{
|
|
char *addr = (char *)except->ExceptionRecord->ExceptionInformation[1];
|
|
if (addr >= DOSMEM_dosmem + DOSMEM_protect && addr < DOSMEM_dosmem + DOSMEM_SIZE)
|
|
{
|
|
if (DOSMEM_InitDosMemory()) return EXCEPTION_CONTINUE_EXECUTION;
|
|
}
|
|
}
|
|
return EXCEPTION_CONTINUE_SEARCH;
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_Init
|
|
*
|
|
* Create the dos memory segments, and store them into the KERNEL
|
|
* exported values.
|
|
*/
|
|
BOOL DOSMEM_Init(void)
|
|
{
|
|
void *addr = (void *)1;
|
|
SIZE_T size = DOSMEM_SIZE - 1;
|
|
|
|
if (NtAllocateVirtualMemory( GetCurrentProcess(), &addr, 0, &size,
|
|
MEM_RESERVE | MEM_COMMIT, PAGE_NOACCESS ))
|
|
{
|
|
ERR( "Cannot allocate DOS memory\n" );
|
|
ExitProcess(1);
|
|
}
|
|
|
|
if (addr <= (void *)DOSMEM_64KB)
|
|
{
|
|
DOSMEM_dosmem = 0;
|
|
DOSMEM_protect = DOSMEM_64KB;
|
|
DOSMEM_sysmem = (char *)0xf0000; /* store sysmem in high addresses for now */
|
|
}
|
|
else
|
|
{
|
|
WARN( "First megabyte not available for DOS address space.\n" );
|
|
DOSMEM_dosmem = addr;
|
|
DOSMEM_protect = 0;
|
|
DOSMEM_sysmem = DOSMEM_dosmem;
|
|
}
|
|
|
|
vectored_handler = AddVectoredExceptionHandler(FALSE, dosmem_handler);
|
|
DOSMEM_0000H = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem,
|
|
DOSMEM_64KB, 0, LDT_FLAGS_DATA );
|
|
DOSMEM_BiosDataSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem + 0x400,
|
|
0x100, 0, LDT_FLAGS_DATA );
|
|
DOSMEM_BiosSysSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_dosmem + 0xf0000,
|
|
DOSMEM_64KB, 0, LDT_FLAGS_DATA );
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_MapLinearToDos
|
|
*
|
|
* Linear address to the DOS address space.
|
|
*/
|
|
UINT DOSMEM_MapLinearToDos(LPVOID ptr)
|
|
{
|
|
if (((char*)ptr >= DOSMEM_dosmem) &&
|
|
((char*)ptr < DOSMEM_dosmem + DOSMEM_SIZE))
|
|
return (char *)ptr - DOSMEM_dosmem;
|
|
return (UINT)ptr;
|
|
}
|
|
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_MapDosToLinear
|
|
*
|
|
* DOS linear address to the linear address space.
|
|
*/
|
|
LPVOID DOSMEM_MapDosToLinear(UINT ptr)
|
|
{
|
|
if (ptr < DOSMEM_SIZE) return DOSMEM_dosmem + ptr;
|
|
return (LPVOID)ptr;
|
|
}
|
|
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_MapRealToLinear
|
|
*
|
|
* Real mode DOS address into a linear pointer
|
|
*/
|
|
LPVOID DOSMEM_MapRealToLinear(DWORD x)
|
|
{
|
|
LPVOID lin;
|
|
|
|
lin = DOSMEM_dosmem + HIWORD(x) * 16 + LOWORD(x);
|
|
TRACE_(selector)("(0x%08x) returns %p.\n", x, lin );
|
|
return lin;
|
|
}
|
|
|
|
/***********************************************************************
|
|
* DOSMEM_AllocBlock
|
|
*
|
|
* Carve a chunk of the DOS memory block (without selector).
|
|
*/
|
|
LPVOID DOSMEM_AllocBlock(UINT size, UINT16* pseg)
|
|
{
|
|
MCB *curr;
|
|
MCB *next = NULL;
|
|
WORD psp;
|
|
|
|
DOSMEM_InitDosMemory();
|
|
|
|
curr = DOSMEM_root_block;
|
|
if (!(psp = DOSVM_psp)) psp = MCB_PSP_DOS;
|
|
|
|
if (pseg) *pseg = 0;
|
|
|
|
TRACE( "(%04xh)\n", size );
|
|
|
|
/* round up to paragraph */
|
|
size = (size + 15) >> 4;
|
|
|
|
#ifdef __DOSMEM_DEBUG__
|
|
DOSMEM_Available(); /* checks the whole MCB list */
|
|
#endif
|
|
|
|
/* loop over all MCB and search the next large enough MCB */
|
|
while (curr)
|
|
{
|
|
if (!MCB_VALID (curr))
|
|
{
|
|
ERR( "MCB List Corrupt\n" );
|
|
MCB_DUMP( curr );
|
|
return NULL;
|
|
}
|
|
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 BOOL already_mapped;
|
|
DWORD old_prot;
|
|
|
|
if (!already_mapped)
|
|
{
|
|
if (DOSMEM_dosmem || !VirtualProtect( NULL, DOSMEM_SIZE, PAGE_EXECUTE_READWRITE, &old_prot ))
|
|
{
|
|
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 = TRUE;
|
|
}
|
|
return TRUE;
|
|
}
|