Sweden-Number/msdos/dosmem.c

837 lines
25 KiB
C

/*
* DOS memory emulation
*
* Copyright 1995 Alexandre Julliard
* Copyright 1996 Marcus Meissner
*/
#include "config.h"
#include "wine/port.h"
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#ifdef HAVE_SYS_MMAN_H
# include <sys/mman.h>
#endif
#include "winbase.h"
#include "wine/winbase16.h"
#include "global.h"
#include "selectors.h"
#include "miscemu.h"
#include "debugtools.h"
DEFAULT_DEBUG_CHANNEL(dosmem);
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 */
DWORD DOSMEM_CollateTable;
/* use 2 low bits of 'size' for the housekeeping */
#define DM_BLOCK_DEBUG 0xABE00000
#define DM_BLOCK_TERMINAL 0x00000001
#define DM_BLOCK_FREE 0x00000002
#define DM_BLOCK_MASK 0x001FFFFC
/*
#define __DOSMEM_DEBUG__
*/
typedef struct {
unsigned size;
} dosmem_entry;
typedef struct {
unsigned blocks;
unsigned free;
} dosmem_info;
#define NEXT_BLOCK(block) \
(dosmem_entry*)(((char*)(block)) + \
sizeof(dosmem_entry) + ((block)->size & DM_BLOCK_MASK))
#define VM_STUB(x) (0x90CF00CD|(x<<8)) /* INT x; IRET; NOP */
#define VM_STUB_SEGMENT 0xf000 /* BIOS segment */
/* DOS memory base */
static char *DOSMEM_dosmem;
/* DOS system base (for interrupt vector table and BIOS data area)
* ...should in theory (i.e. Windows) be equal to DOSMEM_dosmem (NULL),
* but is normally set to 0xf0000 in Wine to allow trapping of NULL pointers,
* and only relocated to NULL when absolutely necessary */
static char *DOSMEM_sysmem;
/* various real-mode code stubs */
WORD DOSMEM_wrap_seg;
WORD DOSMEM_xms_seg;
WORD DOSMEM_dpmi_seg;
WORD DOSMEM_dpmi_sel;
DWORD DOS_LOLSeg;
/***********************************************************************
* DOSMEM_SystemBase
*
* Gets the virtual DOS memory base (interrupt table).
*/
char *DOSMEM_SystemBase(void)
{
return DOSMEM_sysmem;
}
/***********************************************************************
* DOSMEM_MemoryBase
*
* Gets the DOS memory base.
*/
char *DOSMEM_MemoryBase(void)
{
return DOSMEM_dosmem;
}
/***********************************************************************
* DOSMEM_MemoryTop
*
* Gets the DOS memory top.
*/
static char *DOSMEM_MemoryTop(void)
{
return DOSMEM_dosmem+0x9FFFC; /* 640K */
}
/***********************************************************************
* DOSMEM_InfoBlock
*
* Gets the DOS memory info block.
*/
static dosmem_info *DOSMEM_InfoBlock(void)
{
return (dosmem_info*)(DOSMEM_dosmem+0x10000); /* 64K */
}
/***********************************************************************
* DOSMEM_RootBlock
*
* Gets the DOS memory root block.
*/
static dosmem_entry *DOSMEM_RootBlock(void)
{
/* first block has to be paragraph-aligned */
return (dosmem_entry*)(((char*)DOSMEM_InfoBlock()) +
((((sizeof(dosmem_info) + 0xf) & ~0xf) - sizeof(dosmem_entry))));
}
/***********************************************************************
* 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);
}
/***********************************************************************
* DOSMEM_InitDPMI
*
* Allocate the global DPMI RMCB wrapper.
*/
static void DOSMEM_InitDPMI(void)
{
LPSTR ptr;
static const char wrap_code[]={
0xCD,0x31, /* int $0x31 */
0xCB /* lret */
};
static const char enter_xms[]=
{
/* XMS hookable entry point */
0xEB,0x03, /* jmp entry */
0x90,0x90,0x90, /* nop;nop;nop */
/* entry: */
/* real entry point */
/* for simplicity, we'll just use the same hook as DPMI below */
0xCD,0x31, /* int $0x31 */
0xCB /* lret */
};
static const char enter_pm[]=
{
0x50, /* pushw %ax */
0x52, /* pushw %dx */
0x55, /* pushw %bp */
0x89,0xE5, /* movw %sp,%bp */
/* get return CS */
0x8B,0x56,0x08, /* movw 8(%bp),%dx */
/* just call int 31 here to get into protected mode... */
/* it'll check whether it was called from dpmi_seg... */
0xCD,0x31, /* int $0x31 */
/* we are now in the context of a 16-bit relay call */
/* need to fixup our stack;
* 16-bit relay return address will be lost, but we won't worry quite yet */
0x8E,0xD0, /* movw %ax,%ss */
0x66,0x0F,0xB7,0xE5, /* movzwl %bp,%esp */
/* set return CS */
0x89,0x56,0x08, /* movw %dx,8(%bp) */
0x5D, /* popw %bp */
0x5A, /* popw %dx */
0x58, /* popw %ax */
0xCB /* lret */
};
ptr = DOSMEM_GetBlock( sizeof(wrap_code), &DOSMEM_wrap_seg );
memcpy( ptr, wrap_code, sizeof(wrap_code) );
ptr = DOSMEM_GetBlock( sizeof(enter_xms), &DOSMEM_xms_seg );
memcpy( ptr, enter_xms, sizeof(enter_xms) );
ptr = DOSMEM_GetBlock( sizeof(enter_pm), &DOSMEM_dpmi_seg );
memcpy( ptr, enter_pm, sizeof(enter_pm) );
DOSMEM_dpmi_sel = SELECTOR_AllocBlock( ptr, sizeof(enter_pm), WINE_LDT_FLAGS_CODE );
}
BIOSDATA * DOSMEM_BiosData()
{
return (BIOSDATA *)(DOSMEM_sysmem + 0x400);
}
BYTE * DOSMEM_BiosSys()
{
return DOSMEM_dosmem+0xf0000;
}
/***********************************************************************
* DOSMEM_FillBiosSegments
*
* Fill the BIOS data segment with dummy values.
*/
static void DOSMEM_FillBiosSegments(void)
{
BYTE *pBiosSys = DOSMEM_BiosSys();
BYTE *pBiosROMTable = pBiosSys+0xe6f5;
BIOSDATA *pBiosData = DOSMEM_BiosData();
/* bogus 0xe0xx addresses !! Adapt int 0x10/0x1b if change needed */
VIDEOFUNCTIONALITY *pVidFunc = (VIDEOFUNCTIONALITY *)(pBiosSys+0xe000);
VIDEOSTATE *pVidState = (VIDEOSTATE *)(pBiosSys+0xe010);
int i;
/* Clear all unused values */
memset( pBiosData, 0, sizeof(*pBiosData) );
memset( pVidFunc, 0, sizeof(*pVidFunc ) );
memset( pVidState, 0, sizeof(*pVidState) );
/* 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 = INT1A_GetTicksSinceMidnight();
pBiosData->NbHardDisks = 2;
pBiosData->KbdBufferStart = 0x1e;
pBiosData->KbdBufferEnd = 0x3e;
pBiosData->RowsOnScreenMinus1 = 23;
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 */
for (i = 0; i < 7; i++)
pVidFunc->ModeSupport[i] = 0xff;
pVidFunc->ScanlineSupport = 7;
pVidFunc->NumberCharBlocks = 0;
pVidFunc->ActiveCharBlocks = 0;
pVidFunc->MiscFlags = 0x8ff;
pVidFunc->SavePointerFlags = 0x3f;
pVidState->StaticFuncTable = 0xf000e000; /* FIXME: always real mode ? */
pVidState->VideoMode = pBiosData->VideoMode; /* needs updates! */
pVidState->NumberColumns = pBiosData->VideoColumns; /* needs updates! */
pVidState->RegenBufLen = 0;
pVidState->RegenBufAddr = 0;
for (i = 0; i < 8; i++)
pVidState->CursorPos[i] = 0;
pVidState->CursorType = 0x0a0b; /* start/end line */
pVidState->ActivePage = 0;
pVidState->CRTCPort = 0x3da;
pVidState->Port3x8 = 0;
pVidState->Port3x9 = 0;
pVidState->NumberRows = 23; /* number of rows - 1 */
pVidState->BytesPerChar = 0x10;
pVidState->DCCActive = pBiosData->DisplayCombination;
pVidState->DCCAlternate = 0;
pVidState->NumberColors = 16;
pVidState->NumberPages = 1;
pVidState->NumberScanlines = 3; /* (0,1,2,3) = (200,350,400,480) */
pVidState->CharBlockPrimary = 0;
pVidState->CharBlockSecondary = 0;
pVidState->MiscFlags =
(pBiosData->VGASettings & 0x0f)
| ((pBiosData->ModeOptions & 1) << 4); /* cursor emulation */
pVidState->NonVGASupport = 0;
pVidState->VideoMem = (pBiosData->ModeOptions & 0x60 >> 5);
pVidState->SavePointerState = 0;
pVidState->DisplayStatus = 4;
/* BIOS date string */
strcpy((char *)pBiosSys+0xfff5, "13/01/99");
/* BIOS ID */
*(pBiosSys+0xfffe) = 0xfc;
}
/***********************************************************************
* DOSMEM_InitCollateTable
*
* Initialises the collate table (character sorting, language dependent)
*/
static void DOSMEM_InitCollateTable()
{
DWORD x;
unsigned char *tbl;
int i;
x = GlobalDOSAlloc16(258);
DOSMEM_CollateTable = MAKELONG(0,(x>>16));
tbl = DOSMEM_MapRealToLinear(DOSMEM_CollateTable);
*(WORD*)tbl = 0x100;
tbl += 2;
for ( i = 0; i < 0x100; i++) *tbl++ = i;
}
/***********************************************************************
* DOSMEM_InitErrorTable
*
* Initialises the error tables (DOS 5+)
*/
static void DOSMEM_InitErrorTable()
{
#if 0 /* no longer used */
DWORD x;
char *call;
/* We will use a snippet of real mode code that calls */
/* a WINE-only interrupt to handle moving the requested */
/* message into the buffer... */
/* FIXME - There is still something wrong... */
/* FIXME - Find hex values for opcodes...
(On call, AX contains message number
DI contains 'offset' (??)
Resturn, ES:DI points to counted string )
PUSH BX
MOV BX, AX
MOV AX, (arbitrary subfunction number)
INT (WINE-only interrupt)
POP BX
RET
*/
const int code = 4;
const int buffer = 80;
const int SIZE_TO_ALLOCATE = code + buffer;
/* FIXME - Complete rewrite of the table system to save */
/* precious DOS space. Now, we return the 0001:???? as */
/* DOS 4+ (??, it seems to be the case in MS 7.10) treats that */
/* as a special case and programs will use the alternate */
/* interface (a farcall returned with INT 24 (AX = 0x122e, DL = */
/* 0x08) which lets us have a smaller memory footprint anyway. */
x = GlobalDOSAlloc16(SIZE_TO_ALLOCATE);
DOSMEM_ErrorCall = MAKELONG(0,(x>>16));
DOSMEM_ErrorBuffer = DOSMEM_ErrorCall + code;
call = DOSMEM_MapRealToLinear(DOSMEM_ErrorCall);
memset(call, 0, SIZE_TO_ALLOCATE);
#endif
/* Fixme - Copy assembly into buffer here */
}
/***********************************************************************
* DOSMEM_InitMemory
*
* Initialises the DOS memory structures.
*/
static void DOSMEM_InitMemory(void)
{
/* Low 64Kb are reserved for DOS/BIOS so the useable area starts at
* 1000:0000 and ends at 9FFF:FFEF. */
dosmem_info* info_block = DOSMEM_InfoBlock();
dosmem_entry* root_block = DOSMEM_RootBlock();
dosmem_entry* dm;
root_block->size = DOSMEM_MemoryTop() - (((char*)root_block) + sizeof(dosmem_entry));
info_block->blocks = 0;
info_block->free = root_block->size;
dm = NEXT_BLOCK(root_block);
dm->size = DM_BLOCK_TERMINAL;
root_block->size |= DM_BLOCK_FREE
#ifdef __DOSMEM_DEBUG__
| DM_BLOCK_DEBUG
#endif
;
}
/**********************************************************************
* setup_dos_mem
*
* Setup the first megabyte for DOS memory access
*/
static void setup_dos_mem( int dos_init )
{
int sys_offset = 0;
int page_size = getpagesize();
void *addr = wine_anon_mmap( (void *)page_size, 0x110000-page_size,
PROT_READ | PROT_WRITE | PROT_EXEC, 0 );
if (addr == (void *)page_size) /* we got what we wanted */
{
/* now map from address 0 */
addr = wine_anon_mmap( NULL, 0x110000, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_FIXED );
if (addr)
{
ERR("MAP_FIXED failed at address 0 for DOS address space\n" );
ExitProcess(1);
}
/* inform the memory manager that there is a mapping here */
VirtualAlloc( addr, 0x110000, MEM_RESERVE | MEM_SYSTEM, PAGE_EXECUTE_READWRITE );
/* protect the first 64K to catch NULL pointers */
if (!dos_init)
{
VirtualProtect( addr, 0x10000, PAGE_NOACCESS, NULL );
/* move the BIOS and ISR area from 0x00000 to 0xf0000 */
sys_offset += 0xf0000;
}
}
else
{
ERR("Cannot use first megabyte for DOS address space, please report\n" );
if (dos_init) ExitProcess(1);
/* allocate the DOS area somewhere else */
addr = VirtualAlloc( NULL, 0x110000, MEM_COMMIT, PAGE_EXECUTE_READWRITE );
if (!addr)
{
ERR( "Cannot allocate DOS memory\n" );
ExitProcess(1);
}
}
DOSMEM_dosmem = addr;
DOSMEM_sysmem = (char*)addr + sys_offset;
}
/***********************************************************************
* DOSMEM_Init
*
* Create the dos memory segments, and store them into the KERNEL
* exported values.
*/
BOOL DOSMEM_Init(BOOL dos_init)
{
static int already_done, already_mapped;
if (!already_done)
{
setup_dos_mem( dos_init );
DOSMEM_0000H = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem,
0x10000, 0, WINE_LDT_FLAGS_DATA );
DOSMEM_BiosDataSeg = GLOBAL_CreateBlock(GMEM_FIXED,DOSMEM_sysmem + 0x400,
0x100, 0, WINE_LDT_FLAGS_DATA );
DOSMEM_BiosSysSeg = GLOBAL_CreateBlock(GMEM_FIXED,DOSMEM_dosmem+0xf0000,
0x10000, 0, WINE_LDT_FLAGS_DATA );
DOSMEM_FillBiosSegments();
DOSMEM_FillIsrTable();
DOSMEM_InitMemory();
DOSMEM_InitCollateTable();
DOSMEM_InitErrorTable();
DOSMEM_InitDPMI();
already_done = 1;
}
else if (dos_init && !already_mapped)
{
if (DOSMEM_dosmem)
{
ERR( "Needs access to the first megabyte for DOS mode\n" );
ExitProcess(1);
}
MESSAGE( "Warning: unprotecting the first 64KB of memory to allow real-mode calls.\n"
" NULL pointer accesses will no longer be caught.\n" );
VirtualProtect( NULL, 0x10000, PAGE_EXECUTE_READWRITE, NULL );
/* 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;
}
/***********************************************************************
* DOSMEM_Tick
*
* Increment the BIOS tick counter. Called by timer signal handler.
*/
void DOSMEM_Tick( WORD timer )
{
BIOSDATA *pBiosData = DOSMEM_BiosData();
if (pBiosData) pBiosData->Ticks++;
}
/***********************************************************************
* DOSMEM_GetBlock
*
* Carve a chunk of the DOS memory block (without selector).
*/
LPVOID DOSMEM_GetBlock(UINT size, UINT16* pseg)
{
UINT blocksize;
char *block = NULL;
dosmem_info *info_block = DOSMEM_InfoBlock();
dosmem_entry *dm;
#ifdef __DOSMEM_DEBUG_
dosmem_entry *prev = NULL;
#endif
if( size > info_block->free ) return NULL;
dm = DOSMEM_RootBlock();
while (dm && dm->size != DM_BLOCK_TERMINAL)
{
#ifdef __DOSMEM_DEBUG__
if( (dm->size & DM_BLOCK_DEBUG) != DM_BLOCK_DEBUG )
{
WARN("MCB overrun! [prev = 0x%08x]\n", 4 + (UINT)prev);
return NULL;
}
prev = dm;
#endif
if( dm->size & DM_BLOCK_FREE )
{
dosmem_entry *next = NEXT_BLOCK(dm);
while( next->size & DM_BLOCK_FREE ) /* collapse free blocks */
{
dm->size += sizeof(dosmem_entry) + (next->size & DM_BLOCK_MASK);
next->size = (DM_BLOCK_FREE | DM_BLOCK_TERMINAL);
next = NEXT_BLOCK(dm);
}
blocksize = dm->size & DM_BLOCK_MASK;
if( blocksize >= size )
{
block = ((char*)dm) + sizeof(dosmem_entry);
if( blocksize - size > 0x20 )
{
/* split dm so that the next one stays
* paragraph-aligned (and dm loses free bit) */
dm->size = (((size + 0xf + sizeof(dosmem_entry)) & ~0xf) -
sizeof(dosmem_entry));
next = (dosmem_entry*)(((char*)dm) +
sizeof(dosmem_entry) + dm->size);
next->size = (blocksize - (dm->size +
sizeof(dosmem_entry))) | DM_BLOCK_FREE
#ifdef __DOSMEM_DEBUG__
| DM_BLOCK_DEBUG
#endif
;
} else dm->size &= DM_BLOCK_MASK;
info_block->blocks++;
info_block->free -= dm->size;
if( pseg ) *pseg = (block - DOSMEM_dosmem) >> 4;
#ifdef __DOSMEM_DEBUG__
dm->size |= DM_BLOCK_DEBUG;
#endif
break;
}
dm = next;
}
else dm = NEXT_BLOCK(dm);
}
return (LPVOID)block;
}
/***********************************************************************
* DOSMEM_FreeBlock
*/
BOOL DOSMEM_FreeBlock(void* ptr)
{
dosmem_info *info_block = DOSMEM_InfoBlock();
if( ptr >= (void*)(((char*)DOSMEM_RootBlock()) + sizeof(dosmem_entry)) &&
ptr < (void*)DOSMEM_MemoryTop() && !((((char*)ptr)
- DOSMEM_dosmem) & 0xf) )
{
dosmem_entry *dm = (dosmem_entry*)(((char*)ptr) - sizeof(dosmem_entry));
if( !(dm->size & (DM_BLOCK_FREE | DM_BLOCK_TERMINAL))
#ifdef __DOSMEM_DEBUG__
&& ((dm->size & DM_BLOCK_DEBUG) == DM_BLOCK_DEBUG )
#endif
)
{
info_block->blocks--;
info_block->free += dm->size;
dm->size |= DM_BLOCK_FREE;
return TRUE;
}
}
return FALSE;
}
/***********************************************************************
* DOSMEM_ResizeBlock
*/
LPVOID DOSMEM_ResizeBlock(void* ptr, UINT size, UINT16* pseg)
{
char *block = NULL;
dosmem_info *info_block = DOSMEM_InfoBlock();
if( ptr >= (void*)(((char*)DOSMEM_RootBlock()) + sizeof(dosmem_entry)) &&
ptr < (void*)DOSMEM_MemoryTop() && !((((char*)ptr)
- DOSMEM_dosmem) & 0xf) )
{
dosmem_entry *dm = (dosmem_entry*)(((char*)ptr) - sizeof(dosmem_entry));
if( pseg ) *pseg = ((char*)ptr - DOSMEM_dosmem) >> 4;
if( !(dm->size & (DM_BLOCK_FREE | DM_BLOCK_TERMINAL))
)
{
dosmem_entry *next = NEXT_BLOCK(dm);
UINT blocksize, orgsize = dm->size & DM_BLOCK_MASK;
while( next->size & DM_BLOCK_FREE ) /* collapse free blocks */
{
dm->size += sizeof(dosmem_entry) + (next->size & DM_BLOCK_MASK);
next->size = (DM_BLOCK_FREE | DM_BLOCK_TERMINAL);
next = NEXT_BLOCK(dm);
}
blocksize = dm->size & DM_BLOCK_MASK;
if (blocksize >= size)
{
block = ((char*)dm) + sizeof(dosmem_entry);
if( blocksize - size > 0x20 )
{
/* split dm so that the next one stays
* paragraph-aligned (and next gains free bit) */
dm->size = (((size + 0xf + sizeof(dosmem_entry)) & ~0xf) -
sizeof(dosmem_entry));
next = (dosmem_entry*)(((char*)dm) +
sizeof(dosmem_entry) + dm->size);
next->size = (blocksize - (dm->size +
sizeof(dosmem_entry))) | DM_BLOCK_FREE
;
} else dm->size &= DM_BLOCK_MASK;
info_block->free += orgsize - dm->size;
} else {
/* the collapse didn't help, try getting a new block */
block = DOSMEM_GetBlock(size, pseg);
if (block) {
/* we got one, copy the old data there (we do need to, right?) */
memcpy(block, ((char*)dm) + sizeof(dosmem_entry),
(size<orgsize) ? size : orgsize);
/* free old block */
info_block->blocks--;
info_block->free += dm->size;
dm->size |= DM_BLOCK_FREE;
} else {
/* and Bill Gates said 640K should be enough for everyone... */
/* need to split original and collapsed blocks apart again,
* and free the collapsed blocks again, before exiting */
if( blocksize - orgsize > 0x20 )
{
/* split dm so that the next one stays
* paragraph-aligned (and next gains free bit) */
dm->size = (((orgsize + 0xf + sizeof(dosmem_entry)) & ~0xf) -
sizeof(dosmem_entry));
next = (dosmem_entry*)(((char*)dm) +
sizeof(dosmem_entry) + dm->size);
next->size = (blocksize - (dm->size +
sizeof(dosmem_entry))) | DM_BLOCK_FREE
;
} else dm->size &= DM_BLOCK_MASK;
}
}
}
}
return (LPVOID)block;
}
/***********************************************************************
* DOSMEM_Available
*/
UINT DOSMEM_Available(void)
{
UINT blocksize, available = 0;
dosmem_entry *dm;
dm = DOSMEM_RootBlock();
while (dm && dm->size != DM_BLOCK_TERMINAL)
{
#ifdef __DOSMEM_DEBUG__
if( (dm->size & DM_BLOCK_DEBUG) != DM_BLOCK_DEBUG )
{
WARN("MCB overrun! [prev = 0x%08x]\n", 4 + (UINT)prev);
return NULL;
}
prev = dm;
#endif
if( dm->size & DM_BLOCK_FREE )
{
dosmem_entry *next = NEXT_BLOCK(dm);
while( next->size & DM_BLOCK_FREE ) /* collapse free blocks */
{
dm->size += sizeof(dosmem_entry) + (next->size & DM_BLOCK_MASK);
next->size = (DM_BLOCK_FREE | DM_BLOCK_TERMINAL);
next = NEXT_BLOCK(dm);
}
blocksize = dm->size & DM_BLOCK_MASK;
if ( blocksize > available ) available = blocksize;
dm = next;
}
else dm = NEXT_BLOCK(dm);
}
return available;
}
/***********************************************************************
* DOSMEM_MapLinearToDos
*
* Linear address to the DOS address space.
*/
UINT DOSMEM_MapLinearToDos(LPVOID ptr)
{
if (((char*)ptr >= DOSMEM_dosmem) &&
((char*)ptr < DOSMEM_dosmem + 0x100000))
return (UINT)ptr - (UINT)DOSMEM_dosmem;
return (UINT)ptr;
}
/***********************************************************************
* DOSMEM_MapDosToLinear
*
* DOS linear address to the linear address space.
*/
LPVOID DOSMEM_MapDosToLinear(UINT ptr)
{
if (ptr < 0x100000) return (LPVOID)(ptr + (UINT)DOSMEM_dosmem);
return (LPVOID)ptr;
}
/***********************************************************************
* DOSMEM_MapRealToLinear
*
* Real mode DOS address into a linear pointer
*/
LPVOID DOSMEM_MapRealToLinear(DWORD x)
{
LPVOID lin;
lin=DOSMEM_dosmem+(x&0xffff)+(((x&0xffff0000)>>16)*16);
TRACE_(selector)("(0x%08lx) returns %p.\n", x, lin );
return lin;
}
/***********************************************************************
* DOSMEM_AllocSelector
*
* Allocates a protected mode selector for a realmode segment.
*/
WORD DOSMEM_AllocSelector(WORD realsel)
{
HMODULE16 hModule = GetModuleHandle16("KERNEL");
WORD sel;
sel=GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_dosmem+realsel*16, 0x10000,
hModule, WINE_LDT_FLAGS_DATA );
TRACE_(selector)("(0x%04x) returns 0x%04x.\n", realsel,sel);
return sel;
}