Sweden-Number/msdos/dosmem.c

326 lines
10 KiB
C

/*
* DOS memory emulation
*
* Copyright 1995 Alexandre Julliard
* Copyright 1996 Marcus Meissner
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "windows.h"
#include "winbase.h"
#include "global.h"
#include "ldt.h"
#include "miscemu.h"
#include "module.h"
#include "debug.h"
HANDLE16 DOSMEM_BiosSeg; /* BIOS data segment at 0x40:0 */
#pragma pack(1)
typedef struct
{
WORD Com1Addr; /* 00: COM1 I/O address */
WORD Com2Addr; /* 02: COM2 I/O address */
WORD Com3Addr; /* 04: COM3 I/O address */
WORD Com4Addr; /* 06: COM4 I/O address */
WORD Lpt1Addr; /* 08: LPT1 I/O address */
WORD Lpt2Addr; /* 0a: LPT2 I/O address */
WORD Lpt3Addr; /* 0c: LPT3 I/O address */
WORD Lpt4Addr; /* 0e: LPT4 I/O address */
WORD InstalledHardware; /* 10: Installed hardware flags */
BYTE POSTstatus; /* 12: Power-On Self Test status */
WORD MemSize WINE_PACKED; /* 13: Base memory size in Kb */
WORD unused1 WINE_PACKED; /* 15: Manufacturing test scratch pad */
BYTE KbdFlags1; /* 17: Keyboard flags 1 */
BYTE KbdFlags2; /* 18: Keyboard flags 2 */
BYTE unused2; /* 19: Keyboard driver workspace */
WORD NextKbdCharPtr; /* 1a: Next character in kbd buffer */
WORD FirstKbdCharPtr; /* 1c: First character in kbd buffer */
WORD KbdBuffer[16]; /* 1e: Keyboard buffer */
BYTE DisketteStatus1; /* 3e: Diskette recalibrate status */
BYTE DisketteStatus2; /* 3f: Diskette motor status */
BYTE DisketteStatus3; /* 40: Diskette motor timeout */
BYTE DisketteStatus4; /* 41: Diskette last operation status */
BYTE DiskStatus[7]; /* 42: Disk status/command bytes */
BYTE VideoMode; /* 49: Video mode */
WORD VideoColumns; /* 4a: Number of columns */
WORD VideoPageSize; /* 4c: Video page size in bytes */
WORD VideoPageStartAddr; /* 4e: Video page start address */
BYTE VideoCursorPos[16]; /* 50: Cursor position for 8 pages */
WORD VideoCursorType; /* 60: Video cursor type */
BYTE VideoCurPage; /* 62: Video current page */
WORD VideoCtrlAddr WINE_PACKED; /* 63: Video controller address */
BYTE VideoReg1; /* 65: Video mode select register */
BYTE VideoReg2; /* 66: Video CGA palette register */
DWORD ResetEntry WINE_PACKED; /* 67: Warm reset entry point */
BYTE LastIRQ; /* 6b: Last unexpected interrupt */
DWORD Ticks; /* 6c: Ticks since midnight */
BYTE TicksOverflow; /* 70: Timer overflow if past midnight */
BYTE CtrlBreakFlag; /* 71: Ctrl-Break flag */
WORD ResetFlag; /* 72: POST Reset flag */
BYTE DiskOpStatus; /* 74: Last hard-disk operation status */
BYTE NbHardDisks; /* 75: Number of hard disks */
BYTE DiskCtrlByte; /* 76: Disk control byte */
BYTE DiskIOPort; /* 77: Disk I/O port offset */
BYTE LptTimeout[4]; /* 78: Timeouts for parallel ports */
BYTE ComTimeout[4]; /* 7c: Timeouts for serial ports */
WORD KbdBufferStart; /* 80: Keyboard buffer start */
WORD KbdBufferEnd; /* 82: Keyboard buffer end */
} BIOSDATA;
#pragma pack(4)
static BIOSDATA *pBiosData = NULL;
char *DOSMEM_dosmem;
struct dosmem_entry {
struct dosmem_entry *next;
BYTE isfree;
};
/***********************************************************************
* DOSMEM_InitCollateTable
*
* Initialises the collate table (character sorting, language dependend)
*/
DWORD DOSMEM_CollateTable;
static void DOSMEM_InitCollateTable()
{
DWORD x;
unsigned char *tbl;
int i;
x=GlobalDOSAlloc(258);
DOSMEM_CollateTable=MAKELONG(0,(x>>16));
tbl=DOSMEM_RealMode2Linear(DOSMEM_CollateTable);
*(WORD*)tbl = 0x100;
tbl+=2;
for (i=0;i<0x100;i++)
*tbl++=i;
}
/***********************************************************************
* DOSMEM_Init
*
* Create the dos memory segments, and store them into the KERNEL
* exported values.
*/
BOOL32 DOSMEM_Init(void)
{
/* Allocate 1 MB dosmemory */
/* Yes, allocating 1 MB of memory, which is usually not even used, is a
* waste of memory. But I (MM) don't see any easy method to use
* GlobalDOS{Alloc,Free} within an area of memory, with protected mode
* selectors pointing into it, and the possibilty, that the userprogram
* calls SetSelectorBase(,physical_address_in_DOSMEM); that includes
* dynamical enlarging (reallocing) the dosmem area.
* Yes, one could walk the ldt_copy on every realloc() on DOSMEM, but
* this feels more like a hack to me than this current implementation is.
* If you find another, better, method, just change it. -Marcus Meissner
*/
DOSMEM_dosmem = VirtualAlloc(NULL,0x100000,MEM_COMMIT,PAGE_EXECUTE_READWRITE);
if (!DOSMEM_dosmem)
{
fprintf( stderr, "Could not allocate DOS memory.\n" );
return FALSE;
}
DOSMEM_BiosSeg = GLOBAL_CreateBlock(GMEM_FIXED,DOSMEM_dosmem+0x400,0x100,
0, FALSE, FALSE, FALSE, NULL );
DOSMEM_FillBiosSegment();
DOSMEM_InitMemoryHandling();
DOSMEM_InitCollateTable();
return TRUE;
}
/***********************************************************************
* DOSMEM_InitMemoryHandling
*
* Initialises the DOS Memory structures.
*/
void
DOSMEM_InitMemoryHandling()
{
struct dosmem_entry *dm;
dm = (struct dosmem_entry*)(DOSMEM_dosmem+0x10000);
dm->isfree = 1;
dm->next = (struct dosmem_entry*)(DOSMEM_dosmem+0x9FFF0);
dm = dm->next;
dm->isfree = 0;
dm->next = NULL;
}
/***********************************************************************
* DOSMEM_Tick
*
* Increment the BIOS tick counter. Called by timer signal handler.
*/
void DOSMEM_Tick(void)
{
if (pBiosData) pBiosData->Ticks++;
}
/***********************************************************************
* DOSMEM_FillBiosSegment
*
* Fill the BIOS data segment with dummy values.
*/
void DOSMEM_FillBiosSegment(void)
{
pBiosData = (BIOSDATA *)GlobalLock16( DOSMEM_BiosSeg );
/* Clear all unused values */
memset( pBiosData, 0, sizeof(*pBiosData) );
/* FIXME: should check the number of configured drives and ports */
pBiosData->Com1Addr = 0x3e8;
pBiosData->Com2Addr = 0x2e8;
pBiosData->Lpt1Addr = 0x378;
pBiosData->Lpt2Addr = 0x278;
pBiosData->InstalledHardware = 0x8443;
pBiosData->MemSize = 640;
pBiosData->NextKbdCharPtr = 0x1e;
pBiosData->FirstKbdCharPtr = 0x1e;
pBiosData->VideoMode = 0;
pBiosData->VideoColumns = 80;
pBiosData->VideoPageSize = 80 * 25 * 2;
pBiosData->VideoPageStartAddr = 0xb800;
pBiosData->VideoCtrlAddr = 0x3d4;
pBiosData->Ticks = INT1A_GetTicksSinceMidnight();
pBiosData->NbHardDisks = 2;
pBiosData->KbdBufferStart = 0x1e;
pBiosData->KbdBufferEnd = 0x3e;
}
/***********************************************************************
* GlobalDOSAlloc (KERNEL.184)
*
* Allocates a piece of DOS Memory, in the first 1 MB physical memory.
*
* operates on the preallocated DOSMEM_dosmem (1MB). The useable area
* starts at 1000:0000 and ends at 9FFF:FFEF
* Memory allocation strategy is First Fit. (FIXME: Yes,I know that First Fit
* is a rather bad strategy. But since those functions are rather seldom
* called, it's easyness fits the purpose well.)
*
*/
DWORD GlobalDOSAlloc(DWORD size)
{
struct dosmem_entry *dm,*ndm;
DWORD start,blocksize;
WORD sel;
HMODULE16 hModule=GetModuleHandle("KERNEL");
start = 0;
dm = (struct dosmem_entry*)(DOSMEM_dosmem+0x10000);
size = (size+0xf)&~0xf;
while (dm && dm->next) {
blocksize = ((char*)dm->next-(char*)dm)-16;
if ((dm->isfree) && (blocksize>=size)) {
dm->isfree = 0;
start = ((((char*)dm)-DOSMEM_dosmem)+0x10)& ~0xf;
if ((blocksize-size) >= 0x20) {
/* if enough memory is left for a new block
* split this area into two blocks
*/
ndm=(struct dosmem_entry*)((char*)dm+0x10+size);
ndm->isfree = 1;
ndm->next = dm->next;
dm->next = ndm;
}
break;
}
dm=dm->next;
}
if (!start)
return 0;
sel=GLOBAL_CreateBlock(
GMEM_FIXED,DOSMEM_dosmem+start,size,
hModule,FALSE,FALSE,FALSE,NULL
);
return MAKELONG(sel,start>>4);
}
/***********************************************************************
* GlobalDOSFree (KERNEL.185)
*
* Frees allocated dosmemory and corresponding selector.
*/
WORD
GlobalDOSFree(WORD sel)
{
DWORD base;
struct dosmem_entry *dm;
base = GetSelectorBase(sel);
/* base has already been conversed to a physical address */
if (base>=0x100000)
return sel;
dm = (struct dosmem_entry*)(DOSMEM_dosmem+base-0x10);
if (dm->isfree) {
fprintf(stderr,"Freeing already freed DOSMEM.\n");
return 0;
}
dm->isfree = 1;
/* collapse adjunct free blocks into one */
dm = (struct dosmem_entry*)(DOSMEM_dosmem+0x10000);
while (dm && dm->next) {
if (dm->isfree && dm->next->isfree)
dm->next = dm->next->next;
dm = dm->next;
}
GLOBAL_FreeBlock(sel);
return 0;
}
/***********************************************************************
* DOSMEM_RealMode2Linear
*
* Converts a realmode segment:offset address into a linear pointer
*/
LPVOID DOSMEM_RealMode2Linear(DWORD x)
{
LPVOID lin;
lin=DOSMEM_dosmem+(x&0xffff)+(((x&0xffff0000)>>16)*16);
dprintf_selector(stddeb,"DOSMEM_RealMode2Linear(0x%08lx) returns 0x%p.\n",
x,lin
);
return lin;
}
/***********************************************************************
* DOSMEM_AllocSelector
*
* Allocates a protected mode selector for a realmode segment.
*/
WORD DOSMEM_AllocSelector(WORD realsel)
{
HMODULE16 hModule=GetModuleHandle("KERNEL");
WORD sel;
sel=GLOBAL_CreateBlock(
GMEM_FIXED,DOSMEM_dosmem+realsel*16,0x10000,
hModule,FALSE,FALSE,FALSE,NULL
);
dprintf_selector(stddeb,"DOSMEM_AllocSelector(0x%04x) returns 0x%04x.\n",
realsel,sel
);
return sel;
}