Moved LDT handling to libwine.so. Changed the interface to use the
[wine/multimedia.git] / msdos / dosmem.c
blobfd144960c28d0a3640040e216087270b52f49e5d
1 /*
2 * DOS memory emulation
4 * Copyright 1995 Alexandre Julliard
5 * Copyright 1996 Marcus Meissner
6 */
8 #include "config.h"
10 #include <signal.h>
11 #include <stdlib.h>
12 #include <string.h>
13 #include <sys/types.h>
14 #ifdef HAVE_SYS_MMAN_H
15 # include <sys/mman.h>
16 #endif
18 #include "winbase.h"
19 #include "wine/winbase16.h"
21 #include "global.h"
22 #include "ldt.h"
23 #include "selectors.h"
24 #include "miscemu.h"
25 #include "vga.h"
26 #include "dosexe.h"
27 #include "debugtools.h"
29 DEFAULT_DEBUG_CHANNEL(dosmem);
30 DECLARE_DEBUG_CHANNEL(selector);
32 WORD DOSMEM_0000H; /* segment at 0:0 */
33 WORD DOSMEM_BiosDataSeg; /* BIOS data segment at 0x40:0 */
34 WORD DOSMEM_BiosSysSeg; /* BIOS ROM segment at 0xf000:0 */
36 DWORD DOSMEM_CollateTable;
38 /* use 2 low bits of 'size' for the housekeeping */
40 #define DM_BLOCK_DEBUG 0xABE00000
41 #define DM_BLOCK_TERMINAL 0x00000001
42 #define DM_BLOCK_FREE 0x00000002
43 #define DM_BLOCK_MASK 0x001FFFFC
46 #define __DOSMEM_DEBUG__
49 typedef struct {
50 unsigned size;
51 } dosmem_entry;
53 typedef struct {
54 unsigned blocks;
55 unsigned free;
56 } dosmem_info;
58 #define NEXT_BLOCK(block) \
59 (dosmem_entry*)(((char*)(block)) + \
60 sizeof(dosmem_entry) + ((block)->size & DM_BLOCK_MASK))
62 #define VM_STUB(x) (0x90CF00CD|(x<<8)) /* INT x; IRET; NOP */
63 #define VM_STUB_SEGMENT 0xf000 /* BIOS segment */
65 /* DOS memory base */
66 static char *DOSMEM_dosmem;
67 /* DOS system base (for interrupt vector table and BIOS data area)
68 * ...should in theory (i.e. Windows) be equal to DOSMEM_dosmem (NULL),
69 * but is normally set to 0xf0000 in Wine to allow trapping of NULL pointers,
70 * and only relocated to NULL when absolutely necessary */
71 static char *DOSMEM_sysmem;
73 /* various real-mode code stubs */
74 WORD DOSMEM_wrap_seg;
75 WORD DOSMEM_xms_seg;
76 WORD DOSMEM_dpmi_seg;
77 WORD DOSMEM_dpmi_sel;
79 /***********************************************************************
80 * DOSMEM_SystemBase
82 * Gets the virtual DOS memory base (interrupt table).
84 char *DOSMEM_SystemBase(void)
86 return DOSMEM_sysmem;
89 /***********************************************************************
90 * DOSMEM_MemoryBase
92 * Gets the DOS memory base.
94 char *DOSMEM_MemoryBase(void)
96 return DOSMEM_dosmem;
99 /***********************************************************************
100 * DOSMEM_MemoryTop
102 * Gets the DOS memory top.
104 static char *DOSMEM_MemoryTop(void)
106 return DOSMEM_dosmem+0x9FFFC; /* 640K */
109 /***********************************************************************
110 * DOSMEM_InfoBlock
112 * Gets the DOS memory info block.
114 static dosmem_info *DOSMEM_InfoBlock(void)
116 return (dosmem_info*)(DOSMEM_dosmem+0x10000); /* 64K */
119 /***********************************************************************
120 * DOSMEM_RootBlock
122 * Gets the DOS memory root block.
124 static dosmem_entry *DOSMEM_RootBlock(void)
126 /* first block has to be paragraph-aligned */
127 return (dosmem_entry*)(((char*)DOSMEM_InfoBlock()) +
128 ((((sizeof(dosmem_info) + 0xf) & ~0xf) - sizeof(dosmem_entry))));
131 /***********************************************************************
132 * DOSMEM_FillIsrTable
134 * Fill the interrupt table with fake BIOS calls to BIOSSEG (0xf000).
136 * NOTES:
137 * Linux normally only traps INTs performed from or destined to BIOSSEG
138 * for us to handle, if the int_revectored table is empty. Filling the
139 * interrupt table with calls to INT stubs in BIOSSEG allows DOS programs
140 * to hook interrupts, as well as use their familiar retf tricks to call
141 * them, AND let Wine handle any unhooked interrupts transparently.
143 static void DOSMEM_FillIsrTable(void)
145 SEGPTR *isr = (SEGPTR*)DOSMEM_sysmem;
146 int x;
148 for (x=0; x<256; x++) isr[x]=PTR_SEG_OFF_TO_SEGPTR(VM_STUB_SEGMENT,x*4);
151 static void DOSMEM_MakeIsrStubs(void)
153 DWORD *stub = (DWORD*)(DOSMEM_dosmem + (VM_STUB_SEGMENT << 4));
154 int x;
156 for (x=0; x<256; x++) stub[x]=VM_STUB(x);
159 /***********************************************************************
160 * DOSMEM_InitDPMI
162 * Allocate the global DPMI RMCB wrapper.
164 static void DOSMEM_InitDPMI(void)
166 LPSTR ptr;
168 static const char wrap_code[]={
169 0xCD,0x31, /* int $0x31 */
170 0xCB /* lret */
173 static const char enter_xms[]=
175 /* XMS hookable entry point */
176 0xEB,0x03, /* jmp entry */
177 0x90,0x90,0x90, /* nop;nop;nop */
178 /* entry: */
179 /* real entry point */
180 /* for simplicity, we'll just use the same hook as DPMI below */
181 0xCD,0x31, /* int $0x31 */
182 0xCB /* lret */
185 static const char enter_pm[]=
187 0x50, /* pushw %ax */
188 0x52, /* pushw %dx */
189 0x55, /* pushw %bp */
190 0x89,0xE5, /* movw %sp,%bp */
191 /* get return CS */
192 0x8B,0x56,0x08, /* movw 8(%bp),%dx */
193 /* just call int 31 here to get into protected mode... */
194 /* it'll check whether it was called from dpmi_seg... */
195 0xCD,0x31, /* int $0x31 */
196 /* we are now in the context of a 16-bit relay call */
197 /* need to fixup our stack;
198 * 16-bit relay return address will be lost, but we won't worry quite yet */
199 0x8E,0xD0, /* movw %ax,%ss */
200 0x66,0x0F,0xB7,0xE5, /* movzwl %bp,%esp */
201 /* set return CS */
202 0x89,0x56,0x08, /* movw %dx,8(%bp) */
203 0x5D, /* popw %bp */
204 0x5A, /* popw %dx */
205 0x58, /* popw %ax */
206 0xCB /* lret */
209 ptr = DOSMEM_GetBlock( sizeof(wrap_code), &DOSMEM_wrap_seg );
210 memcpy( ptr, wrap_code, sizeof(wrap_code) );
211 ptr = DOSMEM_GetBlock( sizeof(enter_xms), &DOSMEM_xms_seg );
212 memcpy( ptr, enter_xms, sizeof(enter_xms) );
213 ptr = DOSMEM_GetBlock( sizeof(enter_pm), &DOSMEM_dpmi_seg );
214 memcpy( ptr, enter_pm, sizeof(enter_pm) );
215 DOSMEM_dpmi_sel = SELECTOR_AllocBlock( ptr, sizeof(enter_pm), WINE_LDT_FLAGS_CODE );
218 BIOSDATA * DOSMEM_BiosData()
220 return (BIOSDATA *)(DOSMEM_sysmem + 0x400);
223 BYTE * DOSMEM_BiosSys()
225 return DOSMEM_dosmem+0xf0000;
228 struct _DOS_LISTOFLISTS * DOSMEM_LOL()
230 return (struct _DOS_LISTOFLISTS *)DOSMEM_MapRealToLinear
231 (PTR_SEG_OFF_TO_SEGPTR(HIWORD(DOS_LOLSeg),0));
234 /***********************************************************************
235 * DOSMEM_FillBiosSegments
237 * Fill the BIOS data segment with dummy values.
239 static void DOSMEM_FillBiosSegments(void)
241 BYTE *pBiosSys = DOSMEM_BiosSys();
242 BYTE *pBiosROMTable = pBiosSys+0xe6f5;
243 BIOSDATA *pBiosData = DOSMEM_BiosData();
245 /* bogus 0xe0xx addresses !! Adapt int 0x10/0x1b if change needed */
246 VIDEOFUNCTIONALITY *pVidFunc = (VIDEOFUNCTIONALITY *)(pBiosSys+0xe000);
247 VIDEOSTATE *pVidState = (VIDEOSTATE *)(pBiosSys+0xe010);
248 int i;
250 /* Clear all unused values */
251 memset( pBiosData, 0, sizeof(*pBiosData) );
252 memset( pVidFunc, 0, sizeof(*pVidFunc ) );
253 memset( pVidState, 0, sizeof(*pVidState) );
255 /* FIXME: should check the number of configured drives and ports */
257 pBiosData->Com1Addr = 0x3f8;
258 pBiosData->Com2Addr = 0x2f8;
259 pBiosData->Lpt1Addr = 0x378;
260 pBiosData->Lpt2Addr = 0x278;
261 pBiosData->InstalledHardware = 0x5463;
262 pBiosData->MemSize = 640;
263 pBiosData->NextKbdCharPtr = 0x1e;
264 pBiosData->FirstKbdCharPtr = 0x1e;
265 pBiosData->VideoMode = 3;
266 pBiosData->VideoColumns = 80;
267 pBiosData->VideoPageSize = 80 * 25 * 2;
268 pBiosData->VideoPageStartAddr = 0xb800;
269 pBiosData->VideoCtrlAddr = 0x3d4;
270 pBiosData->Ticks = INT1A_GetTicksSinceMidnight();
271 pBiosData->NbHardDisks = 2;
272 pBiosData->KbdBufferStart = 0x1e;
273 pBiosData->KbdBufferEnd = 0x3e;
274 pBiosData->RowsOnScreenMinus1 = 23;
275 pBiosData->BytesPerChar = 0x10;
276 pBiosData->ModeOptions = 0x64;
277 pBiosData->FeatureBitsSwitches = 0xf9;
278 pBiosData->VGASettings = 0x51;
279 pBiosData->DisplayCombination = 0x08;
280 pBiosData->DiskDataRate = 0;
282 /* fill ROM configuration table (values from Award) */
283 *(pBiosROMTable+0x0) = 0x08; /* number of bytes following LO */
284 *(pBiosROMTable+0x1) = 0x00; /* number of bytes following HI */
285 *(pBiosROMTable+0x2) = 0xfc; /* model */
286 *(pBiosROMTable+0x3) = 0x01; /* submodel */
287 *(pBiosROMTable+0x4) = 0x00; /* BIOS revision */
288 *(pBiosROMTable+0x5) = 0x74; /* feature byte 1 */
289 *(pBiosROMTable+0x6) = 0x00; /* feature byte 2 */
290 *(pBiosROMTable+0x7) = 0x00; /* feature byte 3 */
291 *(pBiosROMTable+0x8) = 0x00; /* feature byte 4 */
292 *(pBiosROMTable+0x9) = 0x00; /* feature byte 5 */
295 for (i = 0; i < 7; i++)
296 pVidFunc->ModeSupport[i] = 0xff;
298 pVidFunc->ScanlineSupport = 7;
299 pVidFunc->NumberCharBlocks = 0;
300 pVidFunc->ActiveCharBlocks = 0;
301 pVidFunc->MiscFlags = 0x8ff;
302 pVidFunc->SavePointerFlags = 0x3f;
304 pVidState->StaticFuncTable = 0xf000e000; /* FIXME: always real mode ? */
305 pVidState->VideoMode = pBiosData->VideoMode; /* needs updates! */
306 pVidState->NumberColumns = pBiosData->VideoColumns; /* needs updates! */
307 pVidState->RegenBufLen = 0;
308 pVidState->RegenBufAddr = 0;
310 for (i = 0; i < 8; i++)
311 pVidState->CursorPos[i] = 0;
313 pVidState->CursorType = 0x0a0b; /* start/end line */
314 pVidState->ActivePage = 0;
315 pVidState->CRTCPort = 0x3da;
316 pVidState->Port3x8 = 0;
317 pVidState->Port3x9 = 0;
318 pVidState->NumberRows = 23; /* number of rows - 1 */
319 pVidState->BytesPerChar = 0x10;
320 pVidState->DCCActive = pBiosData->DisplayCombination;
321 pVidState->DCCAlternate = 0;
322 pVidState->NumberColors = 16;
323 pVidState->NumberPages = 1;
324 pVidState->NumberScanlines = 3; /* (0,1,2,3) = (200,350,400,480) */
325 pVidState->CharBlockPrimary = 0;
326 pVidState->CharBlockSecondary = 0;
327 pVidState->MiscFlags =
328 (pBiosData->VGASettings & 0x0f)
329 | ((pBiosData->ModeOptions & 1) << 4); /* cursor emulation */
330 pVidState->NonVGASupport = 0;
331 pVidState->VideoMem = (pBiosData->ModeOptions & 0x60 >> 5);
332 pVidState->SavePointerState = 0;
333 pVidState->DisplayStatus = 4;
335 /* BIOS date string */
336 strcpy((char *)pBiosSys+0xfff5, "13/01/99");
338 /* BIOS ID */
339 *(pBiosSys+0xfffe) = 0xfc;
342 /***********************************************************************
343 * DOSMEM_InitCollateTable
345 * Initialises the collate table (character sorting, language dependent)
347 static void DOSMEM_InitCollateTable()
349 DWORD x;
350 unsigned char *tbl;
351 int i;
353 x = GlobalDOSAlloc16(258);
354 DOSMEM_CollateTable = MAKELONG(0,(x>>16));
355 tbl = DOSMEM_MapRealToLinear(DOSMEM_CollateTable);
356 *(WORD*)tbl = 0x100;
357 tbl += 2;
358 for ( i = 0; i < 0x100; i++) *tbl++ = i;
361 /***********************************************************************
362 * DOSMEM_InitErrorTable
364 * Initialises the error tables (DOS 5+)
366 static void DOSMEM_InitErrorTable()
368 #if 0 /* no longer used */
369 DWORD x;
370 char *call;
372 /* We will use a snippet of real mode code that calls */
373 /* a WINE-only interrupt to handle moving the requested */
374 /* message into the buffer... */
376 /* FIXME - There is still something wrong... */
378 /* FIXME - Find hex values for opcodes...
380 (On call, AX contains message number
381 DI contains 'offset' (??)
382 Resturn, ES:DI points to counted string )
384 PUSH BX
385 MOV BX, AX
386 MOV AX, (arbitrary subfunction number)
387 INT (WINE-only interrupt)
388 POP BX
393 const int code = 4;
394 const int buffer = 80;
395 const int SIZE_TO_ALLOCATE = code + buffer;
397 /* FIXME - Complete rewrite of the table system to save */
398 /* precious DOS space. Now, we return the 0001:???? as */
399 /* DOS 4+ (??, it seems to be the case in MS 7.10) treats that */
400 /* as a special case and programs will use the alternate */
401 /* interface (a farcall returned with INT 24 (AX = 0x122e, DL = */
402 /* 0x08) which lets us have a smaller memory footprint anyway. */
404 x = GlobalDOSAlloc16(SIZE_TO_ALLOCATE);
406 DOSMEM_ErrorCall = MAKELONG(0,(x>>16));
407 DOSMEM_ErrorBuffer = DOSMEM_ErrorCall + code;
409 call = DOSMEM_MapRealToLinear(DOSMEM_ErrorCall);
411 memset(call, 0, SIZE_TO_ALLOCATE);
412 #endif
413 /* Fixme - Copy assembly into buffer here */
416 /***********************************************************************
417 * DOSMEM_InitMemory
419 * Initialises the DOS memory structures.
421 static void DOSMEM_InitMemory(void)
423 /* Low 64Kb are reserved for DOS/BIOS so the useable area starts at
424 * 1000:0000 and ends at 9FFF:FFEF. */
426 dosmem_info* info_block = DOSMEM_InfoBlock();
427 dosmem_entry* root_block = DOSMEM_RootBlock();
428 dosmem_entry* dm;
430 root_block->size = DOSMEM_MemoryTop() - (((char*)root_block) + sizeof(dosmem_entry));
432 info_block->blocks = 0;
433 info_block->free = root_block->size;
435 dm = NEXT_BLOCK(root_block);
436 dm->size = DM_BLOCK_TERMINAL;
437 root_block->size |= DM_BLOCK_FREE
438 #ifdef __DOSMEM_DEBUG__
439 | DM_BLOCK_DEBUG;
440 #endif
444 /**********************************************************************
445 * setup_dos_mem
447 * Setup the first megabyte for DOS memory access
449 static void setup_dos_mem( int dos_init )
451 int sys_offset = 0;
452 int page_size = VIRTUAL_GetPageSize();
453 void *addr = VIRTUAL_mmap( -1, (void *)page_size, 0x110000-page_size, 0,
454 PROT_READ | PROT_WRITE | PROT_EXEC, 0 );
455 if (addr == (void *)page_size) /* we got what we wanted */
457 /* now map from address 0 */
458 addr = VIRTUAL_mmap( -1, NULL, 0x110000, 0,
459 PROT_READ | PROT_WRITE | PROT_EXEC, MAP_FIXED );
460 if (addr)
462 ERR("MAP_FIXED failed at address 0 for DOS address space\n" );
463 ExitProcess(1);
466 /* inform the memory manager that there is a mapping here */
467 VirtualAlloc( addr, 0x110000, MEM_RESERVE | MEM_SYSTEM, PAGE_EXECUTE_READWRITE );
469 /* protect the first 64K to catch NULL pointers */
470 if (!dos_init)
472 VirtualProtect( addr, 0x10000, PAGE_NOACCESS, NULL );
473 /* move the BIOS and ISR area from 0x00000 to 0xf0000 */
474 sys_offset += 0xf0000;
477 else
479 ERR("Cannot use first megabyte for DOS address space, please report\n" );
480 if (dos_init) ExitProcess(1);
481 /* allocate the DOS area somewhere else */
482 addr = VirtualAlloc( NULL, 0x110000, MEM_COMMIT, PAGE_EXECUTE_READWRITE );
483 if (!addr)
485 ERR( "Cannot allocate DOS memory\n" );
486 ExitProcess(1);
489 DOSMEM_dosmem = addr;
490 DOSMEM_sysmem = (char*)addr + sys_offset;
494 /***********************************************************************
495 * DOSMEM_Init
497 * Create the dos memory segments, and store them into the KERNEL
498 * exported values.
500 BOOL DOSMEM_Init(BOOL dos_init)
502 static int already_done, already_mapped;
504 if (!already_done)
506 setup_dos_mem( dos_init );
508 DOSMEM_0000H = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem,
509 0x10000, 0, WINE_LDT_FLAGS_DATA );
510 DOSMEM_BiosDataSeg = GLOBAL_CreateBlock(GMEM_FIXED,DOSMEM_sysmem + 0x400,
511 0x100, 0, WINE_LDT_FLAGS_DATA );
512 DOSMEM_BiosSysSeg = GLOBAL_CreateBlock(GMEM_FIXED,DOSMEM_dosmem+0xf0000,
513 0x10000, 0, WINE_LDT_FLAGS_DATA );
514 DOSMEM_FillBiosSegments();
515 DOSMEM_FillIsrTable();
516 DOSMEM_InitMemory();
517 DOSMEM_InitCollateTable();
518 DOSMEM_InitErrorTable();
519 DOSMEM_InitDPMI();
520 DOSDEV_InstallDOSDevices();
521 already_done = 1;
523 else if (dos_init && !already_mapped)
525 if (DOSMEM_dosmem)
527 ERR( "Needs access to the first megabyte for DOS mode\n" );
528 ExitProcess(1);
530 MESSAGE( "Warning: unprotecting the first 64KB of memory to allow real-mode calls.\n"
531 " NULL pointer accesses will no longer be caught.\n" );
532 VirtualProtect( NULL, 0x10000, PAGE_EXECUTE_READWRITE, NULL );
533 /* copy the BIOS and ISR area down */
534 memcpy( DOSMEM_dosmem, DOSMEM_sysmem, 0x400 + 0x100 );
535 DOSMEM_sysmem = DOSMEM_dosmem;
536 SetSelectorBase( DOSMEM_0000H, 0 );
537 SetSelectorBase( DOSMEM_BiosDataSeg, 0x400 );
538 /* we may now need the actual interrupt stubs, and since we've just moved the
539 * interrupt vector table away, we can fill the area with stubs instead... */
540 DOSMEM_MakeIsrStubs();
541 already_mapped = 1;
543 return TRUE;
547 /***********************************************************************
548 * DOSMEM_Tick
550 * Increment the BIOS tick counter. Called by timer signal handler.
552 void DOSMEM_Tick( WORD timer )
554 BIOSDATA *pBiosData = DOSMEM_BiosData();
555 if (pBiosData) pBiosData->Ticks++;
558 /***********************************************************************
559 * DOSMEM_GetBlock
561 * Carve a chunk of the DOS memory block (without selector).
563 LPVOID DOSMEM_GetBlock(UINT size, UINT16* pseg)
565 UINT blocksize;
566 char *block = NULL;
567 dosmem_info *info_block = DOSMEM_InfoBlock();
568 dosmem_entry *dm;
569 #ifdef __DOSMEM_DEBUG_
570 dosmem_entry *prev = NULL;
571 #endif
573 if( size > info_block->free ) return NULL;
574 dm = DOSMEM_RootBlock();
576 while (dm && dm->size != DM_BLOCK_TERMINAL)
578 #ifdef __DOSMEM_DEBUG__
579 if( (dm->size & DM_BLOCK_DEBUG) != DM_BLOCK_DEBUG )
581 WARN("MCB overrun! [prev = 0x%08x]\n", 4 + (UINT)prev);
582 return NULL;
584 prev = dm;
585 #endif
586 if( dm->size & DM_BLOCK_FREE )
588 dosmem_entry *next = NEXT_BLOCK(dm);
590 while( next->size & DM_BLOCK_FREE ) /* collapse free blocks */
592 dm->size += sizeof(dosmem_entry) + (next->size & DM_BLOCK_MASK);
593 next->size = (DM_BLOCK_FREE | DM_BLOCK_TERMINAL);
594 next = NEXT_BLOCK(dm);
597 blocksize = dm->size & DM_BLOCK_MASK;
598 if( blocksize >= size )
600 block = ((char*)dm) + sizeof(dosmem_entry);
601 if( blocksize - size > 0x20 )
603 /* split dm so that the next one stays
604 * paragraph-aligned (and dm loses free bit) */
606 dm->size = (((size + 0xf + sizeof(dosmem_entry)) & ~0xf) -
607 sizeof(dosmem_entry));
608 next = (dosmem_entry*)(((char*)dm) +
609 sizeof(dosmem_entry) + dm->size);
610 next->size = (blocksize - (dm->size +
611 sizeof(dosmem_entry))) | DM_BLOCK_FREE
612 #ifdef __DOSMEM_DEBUG__
613 | DM_BLOCK_DEBUG
614 #endif
616 } else dm->size &= DM_BLOCK_MASK;
618 info_block->blocks++;
619 info_block->free -= dm->size;
620 if( pseg ) *pseg = (block - DOSMEM_dosmem) >> 4;
621 #ifdef __DOSMEM_DEBUG__
622 dm->size |= DM_BLOCK_DEBUG;
623 #endif
624 break;
626 dm = next;
628 else dm = NEXT_BLOCK(dm);
630 return (LPVOID)block;
633 /***********************************************************************
634 * DOSMEM_FreeBlock
636 BOOL DOSMEM_FreeBlock(void* ptr)
638 dosmem_info *info_block = DOSMEM_InfoBlock();
640 if( ptr >= (void*)(((char*)DOSMEM_RootBlock()) + sizeof(dosmem_entry)) &&
641 ptr < (void*)DOSMEM_MemoryTop() && !((((char*)ptr)
642 - DOSMEM_dosmem) & 0xf) )
644 dosmem_entry *dm = (dosmem_entry*)(((char*)ptr) - sizeof(dosmem_entry));
646 if( !(dm->size & (DM_BLOCK_FREE | DM_BLOCK_TERMINAL))
647 #ifdef __DOSMEM_DEBUG__
648 && ((dm->size & DM_BLOCK_DEBUG) == DM_BLOCK_DEBUG )
649 #endif
652 info_block->blocks--;
653 info_block->free += dm->size;
655 dm->size |= DM_BLOCK_FREE;
656 return TRUE;
659 return FALSE;
662 /***********************************************************************
663 * DOSMEM_ResizeBlock
665 LPVOID DOSMEM_ResizeBlock(void* ptr, UINT size, UINT16* pseg)
667 char *block = NULL;
668 dosmem_info *info_block = DOSMEM_InfoBlock();
670 if( ptr >= (void*)(((char*)DOSMEM_RootBlock()) + sizeof(dosmem_entry)) &&
671 ptr < (void*)DOSMEM_MemoryTop() && !((((char*)ptr)
672 - DOSMEM_dosmem) & 0xf) )
674 dosmem_entry *dm = (dosmem_entry*)(((char*)ptr) - sizeof(dosmem_entry));
676 if( pseg ) *pseg = ((char*)ptr - DOSMEM_dosmem) >> 4;
678 if( !(dm->size & (DM_BLOCK_FREE | DM_BLOCK_TERMINAL))
681 dosmem_entry *next = NEXT_BLOCK(dm);
682 UINT blocksize, orgsize = dm->size & DM_BLOCK_MASK;
684 while( next->size & DM_BLOCK_FREE ) /* collapse free blocks */
686 dm->size += sizeof(dosmem_entry) + (next->size & DM_BLOCK_MASK);
687 next->size = (DM_BLOCK_FREE | DM_BLOCK_TERMINAL);
688 next = NEXT_BLOCK(dm);
691 blocksize = dm->size & DM_BLOCK_MASK;
692 if (blocksize >= size)
694 block = ((char*)dm) + sizeof(dosmem_entry);
695 if( blocksize - size > 0x20 )
697 /* split dm so that the next one stays
698 * paragraph-aligned (and next gains free bit) */
700 dm->size = (((size + 0xf + sizeof(dosmem_entry)) & ~0xf) -
701 sizeof(dosmem_entry));
702 next = (dosmem_entry*)(((char*)dm) +
703 sizeof(dosmem_entry) + dm->size);
704 next->size = (blocksize - (dm->size +
705 sizeof(dosmem_entry))) | DM_BLOCK_FREE
707 } else dm->size &= DM_BLOCK_MASK;
709 info_block->free += orgsize - dm->size;
710 } else {
711 /* the collapse didn't help, try getting a new block */
712 block = DOSMEM_GetBlock(size, pseg);
713 if (block) {
714 /* we got one, copy the old data there (we do need to, right?) */
715 memcpy(block, ((char*)dm) + sizeof(dosmem_entry),
716 (size<orgsize) ? size : orgsize);
717 /* free old block */
718 info_block->blocks--;
719 info_block->free += dm->size;
721 dm->size |= DM_BLOCK_FREE;
722 } else {
723 /* and Bill Gates said 640K should be enough for everyone... */
725 /* need to split original and collapsed blocks apart again,
726 * and free the collapsed blocks again, before exiting */
727 if( blocksize - orgsize > 0x20 )
729 /* split dm so that the next one stays
730 * paragraph-aligned (and next gains free bit) */
732 dm->size = (((orgsize + 0xf + sizeof(dosmem_entry)) & ~0xf) -
733 sizeof(dosmem_entry));
734 next = (dosmem_entry*)(((char*)dm) +
735 sizeof(dosmem_entry) + dm->size);
736 next->size = (blocksize - (dm->size +
737 sizeof(dosmem_entry))) | DM_BLOCK_FREE
739 } else dm->size &= DM_BLOCK_MASK;
744 return (LPVOID)block;
748 /***********************************************************************
749 * DOSMEM_Available
751 UINT DOSMEM_Available(void)
753 UINT blocksize, available = 0;
754 dosmem_entry *dm;
756 dm = DOSMEM_RootBlock();
758 while (dm && dm->size != DM_BLOCK_TERMINAL)
760 #ifdef __DOSMEM_DEBUG__
761 if( (dm->size & DM_BLOCK_DEBUG) != DM_BLOCK_DEBUG )
763 WARN("MCB overrun! [prev = 0x%08x]\n", 4 + (UINT)prev);
764 return NULL;
766 prev = dm;
767 #endif
768 if( dm->size & DM_BLOCK_FREE )
770 dosmem_entry *next = NEXT_BLOCK(dm);
772 while( next->size & DM_BLOCK_FREE ) /* collapse free blocks */
774 dm->size += sizeof(dosmem_entry) + (next->size & DM_BLOCK_MASK);
775 next->size = (DM_BLOCK_FREE | DM_BLOCK_TERMINAL);
776 next = NEXT_BLOCK(dm);
779 blocksize = dm->size & DM_BLOCK_MASK;
780 if ( blocksize > available ) available = blocksize;
781 dm = next;
783 else dm = NEXT_BLOCK(dm);
785 return available;
789 /***********************************************************************
790 * DOSMEM_MapLinearToDos
792 * Linear address to the DOS address space.
794 UINT DOSMEM_MapLinearToDos(LPVOID ptr)
796 if (((char*)ptr >= DOSMEM_dosmem) &&
797 ((char*)ptr < DOSMEM_dosmem + 0x100000))
798 return (UINT)ptr - (UINT)DOSMEM_dosmem;
799 return (UINT)ptr;
803 /***********************************************************************
804 * DOSMEM_MapDosToLinear
806 * DOS linear address to the linear address space.
808 LPVOID DOSMEM_MapDosToLinear(UINT ptr)
810 if (ptr < 0x100000) return (LPVOID)(ptr + (UINT)DOSMEM_dosmem);
811 return (LPVOID)ptr;
815 /***********************************************************************
816 * DOSMEM_MapRealToLinear
818 * Real mode DOS address into a linear pointer
820 LPVOID DOSMEM_MapRealToLinear(DWORD x)
822 LPVOID lin;
824 lin=DOSMEM_dosmem+(x&0xffff)+(((x&0xffff0000)>>16)*16);
825 TRACE_(selector)("(0x%08lx) returns 0x%p.\n", x, lin );
826 return lin;
829 /***********************************************************************
830 * DOSMEM_AllocSelector
832 * Allocates a protected mode selector for a realmode segment.
834 WORD DOSMEM_AllocSelector(WORD realsel)
836 HMODULE16 hModule = GetModuleHandle16("KERNEL");
837 WORD sel;
839 sel=GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_dosmem+realsel*16, 0x10000,
840 hModule, WINE_LDT_FLAGS_DATA );
841 TRACE_(selector)("(0x%04x) returns 0x%04x.\n", realsel,sel);
842 return sel;