msdos/dpmi.c

   1 /*
   2  * DPMI 0.9 emulation
   3  *
   4  * Copyright 1995 Alexandre Julliard
   5  */
   6
   7 #include <unistd.h>
   8 #include <string.h>
   9 #include "windows.h"
  10 #include "heap.h"
  11 #include "global.h"
  12 #include "ldt.h"
  13 #include "module.h"
  14 #include "miscemu.h"
  15 #include "drive.h"
  16 #include "msdos.h"
  17 #include "task.h"
  18 #include "dosexe.h"
  19 #include "toolhelp.h"
  20 #include "debug.h"
  21 #include "selectors.h"
  22 #include "thread.h"
  23 #include "process.h"
  24 #include "stackframe.h"
  25 #include "callback.h"
  26
  27 #define DOS_GET_DRIVE(reg) ((reg) ? (reg) - 1 : DRIVE_GetCurrentDrive())
  28
  29 void CreateBPB(int drive, BYTE *data, BOOL16 limited);  /* defined in int21.c */
  30
  31 static void* lastvalloced = NULL;
  32
  33 /* Structure for real-mode callbacks */
  34 typedef struct
  35 {
  36     DWORD edi;
  37     DWORD esi;
  38     DWORD ebp;
  39     DWORD reserved;
  40     DWORD ebx;
  41     DWORD edx;
  42     DWORD ecx;
  43     DWORD eax;
  44     WORD  fl;
  45     WORD  es;
  46     WORD  ds;
  47     WORD  fs;
  48     WORD  gs;
  49     WORD  ip;
  50     WORD  cs;
  51     WORD  sp;
  52     WORD  ss;
  53 } REALMODECALL;
  54
  55
  56
  57 typedef struct tagRMCB {
  58     DWORD address;
  59     struct tagRMCB *next;
  60
  61 } RMCB;
  62
  63 static RMCB *FirstRMCB = NULL;
  64
  65 /**********************************************************************
  66  *          DPMI_xalloc
  67  * special virtualalloc, allocates lineary monoton growing memory.
  68  * (the usual VirtualAlloc does not satisfy that restriction)
  69  */
  70 static LPVOID
  71 DPMI_xalloc(int len) {
  72         LPVOID  ret;
  73         LPVOID  oldlastv = lastvalloced;
  74
  75         if (lastvalloced) {
  76                 int     xflag = 0;
  77                 ret = NULL;
  78                 while (!ret) {
  79                         ret=VirtualAlloc(lastvalloced,len,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
  80                         if (!ret)
  81                                 lastvalloced+=0x10000;
  82                         /* we failed to allocate one in the first round.
  83                          * try non-linear
  84                          */
  85                         if (!xflag && (lastvalloced<oldlastv)) { /* wrapped */
  86                                 FIXME(int31,"failed to allocate lineary growing memory (%d bytes), using non-linear growing...\n",len);
  87                                 xflag++;
  88                         }
  89                         /* if we even fail to allocate something in the next
  90                          * round, return NULL
  91                          */
  92                         if ((xflag==1) && (lastvalloced >= oldlastv))
  93                                 xflag++;
  94                         if ((xflag==2) && (lastvalloced < oldlastv)) {
  95                                 FIXME(int31,"failed to allocate any memory of %d bytes!\n",len);
  96                                 return NULL;
  97                         }
  98                 }
  99         } else
 100                  ret=VirtualAlloc(NULL,len,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
 101         lastvalloced = (LPVOID)(((DWORD)ret+len+0xffff)&~0xffff);
 102         return ret;
 103 }
 104
 105 static void
 106 DPMI_xfree(LPVOID ptr) {
 107         VirtualFree(ptr,0,MEM_RELEASE);
 108 }
 109
 110 /* FIXME: perhaps we could grow this mapped area... */
 111 static LPVOID
 112 DPMI_xrealloc(LPVOID ptr,int newsize) {
 113         MEMORY_BASIC_INFORMATION        mbi;
 114         LPVOID                          newptr;
 115
 116         newptr = DPMI_xalloc(newsize);
 117         if (ptr) {
 118                 if (!VirtualQuery(ptr,&mbi,sizeof(mbi))) {
 119                         FIXME(int31,"realloc of DPMI_xallocd region %p?\n",ptr);
 120                         return NULL;
 121                 }
 122                 if (mbi.State == MEM_FREE) {
 123                         FIXME(int31,"realloc of DPMI_xallocd region %p?\n",ptr);
 124                         return NULL;
 125                 }
 126                 /* We do not shrink allocated memory. most reallocs
 127                  * only do grows anyway
 128                  */
 129                 if (newsize<=mbi.RegionSize)
 130                         return ptr;
 131                 memcpy(newptr,ptr,mbi.RegionSize);
 132                 DPMI_xfree(ptr);
 133         }
 134         return newptr;
 135 }
 136 /**********************************************************************
 137  *          INT_GetRealModeContext
 138  */
 139 static void INT_GetRealModeContext( REALMODECALL *call, CONTEXT *context )
 140 {
 141     EAX_reg(context) = call->eax;
 142     EBX_reg(context) = call->ebx;
 143     ECX_reg(context) = call->ecx;
 144     EDX_reg(context) = call->edx;
 145     ESI_reg(context) = call->esi;
 146     EDI_reg(context) = call->edi;
 147     EBP_reg(context) = call->ebp;
 148     EFL_reg(context) = call->fl | V86_FLAG;
 149     EIP_reg(context) = call->ip;
 150     ESP_reg(context) = call->sp;
 151     CS_reg(context)  = call->cs;
 152     DS_reg(context)  = call->ds;
 153     ES_reg(context)  = call->es;
 154     FS_reg(context)  = call->fs;
 155     GS_reg(context)  = call->gs;
 156     (char*)V86BASE(context) = DOSMEM_MemoryBase(0);
 157 }
 158
 159
 160 /**********************************************************************
 161  *          INT_SetRealModeContext
 162  */
 163 static void INT_SetRealModeContext( REALMODECALL *call, CONTEXT *context )
 164 {
 165     call->eax = EAX_reg(context);
 166     call->ebx = EBX_reg(context);
 167     call->ecx = ECX_reg(context);
 168     call->edx = EDX_reg(context);
 169     call->esi = ESI_reg(context);
 170     call->edi = EDI_reg(context);
 171     call->ebp = EBP_reg(context);
 172     call->fl  = FL_reg(context);
 173     call->ip  = IP_reg(context);
 174     call->sp  = SP_reg(context);
 175     call->cs  = CS_reg(context);
 176     call->ds  = DS_reg(context);
 177     call->es  = ES_reg(context);
 178     call->fs  = FS_reg(context);
 179     call->gs  = GS_reg(context);
 180 }
 181
 182
 183 /**********************************************************************
 184  *          DPMI_CallRMProc
 185  *
 186  * This routine does the hard work of calling a real mode procedure.
 187  */
 188 int DPMI_CallRMProc( CONTEXT *context, LPWORD stack, int args, int iret )
 189 {
 190     LPWORD stack16;
 191     THDB *thdb = THREAD_Current();
 192     LPVOID addr;
 193     TDB *pTask = (TDB *)GlobalLock16( GetCurrentTask() );
 194     NE_MODULE *pModule = pTask ? NE_GetPtr( pTask->hModule ) : NULL;
 195     int alloc = 0;
 196     WORD sel;
 197     SEGPTR seg_addr;
 198
 199     GlobalUnlock16( GetCurrentTask() );
 200
 201     TRACE(int31, "EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 202                  EAX_reg(context), EBX_reg(context), ECX_reg(context), EDX_reg(context) );
 203     TRACE(int31, "ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x, %d WORD arguments\n",
 204                  ESI_reg(context), EDI_reg(context), ES_reg(context), DS_reg(context),
 205                  CS_reg(context), IP_reg(context), args );
 206
 207 #ifdef MZ_SUPPORTED
 208     FIXME(int31,"DPMI real-mode call using DOS VM task system, untested!\n");
 209     if (!pModule->lpDosTask) {
 210         TRACE(int31,"creating VM86 task\n");
 211         if (MZ_InitTask( MZ_AllocDPMITask( pModule->self ) ) < 32) {
 212             ERR(int31,"could not setup VM86 task\n");
 213             return 1;
 214         }
 215     }
 216     if (!SS_reg(context)) {
 217         alloc = 1; /* allocate default stack */
 218         stack16 = addr = DOSMEM_GetBlock( pModule->self, 64, &(SS_reg(context)) );
 219         SP_reg(context) = 64-2;
 220         if (!stack16) {
 221             ERR(int31,"could not allocate default stack\n");
 222             return 1;
 223         }
 224     } else {
 225         stack16 = CTX_SEG_OFF_TO_LIN(context, SS_reg(context), SP_reg(context));
 226         addr = NULL; /* avoid gcc warning */
 227     }
 228     SP_reg(context) -= args*sizeof(WORD) + (iret?1:0);
 229 #else
 230     stack16 = THREAD_STACK16(thdb);
 231 #endif
 232     stack16 -= args;
 233     if (args) memcpy(stack16, stack, args*sizeof(WORD) );
 234     /* push flags if iret */
 235     if (iret) {
 236         stack16--; args++;
 237         *stack16 = FL_reg(context);
 238     }
 239 #ifdef MZ_SUPPORTED
 240     /* push return address (return to interrupt wrapper) */
 241     *(--stack16) = pModule->lpDosTask->dpmi_seg;
 242     *(--stack16) = pModule->lpDosTask->wrap_ofs;
 243     /* push call address */
 244     *(--stack16) = CS_reg(context);
 245     *(--stack16) = IP_reg(context);
 246     /* adjust stack */
 247     SP_reg(context) -= 4*sizeof(WORD);
 248     /* set initial CS:IP to the wrapper's "lret" */
 249     CS_reg(context) = pModule->lpDosTask->dpmi_seg;
 250     IP_reg(context) = pModule->lpDosTask->call_ofs;
 251     TRACE(int31,"entering real mode...\n");
 252     DOSVM_Enter( context );
 253     TRACE(int31,"returned from real-mode call\n");
 254     if (alloc) DOSMEM_FreeBlock( pModule->self, addr );
 255 #else
 256     addr = CTX_SEG_OFF_TO_LIN(context, CS_reg(context), IP_reg(context));
 257     sel = SELECTOR_AllocBlock( addr, 0x10000, SEGMENT_CODE, FALSE, FALSE );
 258     seg_addr = PTR_SEG_OFF_TO_SEGPTR( sel, 0 );
 259
 260     CS_reg(context) = HIWORD(seg_addr);
 261     IP_reg(context) = LOWORD(seg_addr);
 262     EBP_reg(context) = OFFSETOF( thdb->cur_stack )
 263                                + (WORD)&((STACK16FRAME*)0)->bp;
 264     Callbacks->CallRegisterShortProc(context, args*sizeof(WORD));
 265     UnMapLS(seg_addr);
 266 #endif
 267     return 0;
 268 }
 269
 270
 271 /**********************************************************************
 272  *          INT_DoRealModeInt
 273  */
 274 static void INT_DoRealModeInt( CONTEXT *context )
 275 {
 276     CONTEXT realmode_ctx;
 277     FARPROC16 rm_int = INT_GetRMHandler( BL_reg(context) );
 278     REALMODECALL *call = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context),
 279                                                           DI_reg(context) );
 280     INT_GetRealModeContext( call, &realmode_ctx );
 281
 282 #ifdef MZ_SUPPORTED
 283     /* we need to check if a real-mode program has hooked the interrupt */
 284     if (HIWORD(rm_int)!=0xF000) {
 285         /* yup, which means we need to switch to real mode... */
 286         CS_reg(&realmode_ctx) = HIWORD(rm_int);
 287         EIP_reg(&realmode_ctx) = LOWORD(rm_int);
 288         if (DPMI_CallRMProc( &realmode_ctx, NULL, 0, TRUE))
 289           SET_CFLAG(context);
 290     } else
 291 #endif
 292     {
 293         RESET_CFLAG(context);
 294         if (INT_RealModeInterrupt( BL_reg(context), &realmode_ctx ))
 295           SET_CFLAG(context);
 296         if (EFL_reg(context)&1) {
 297           FIXME(int31,"%02x: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 298                 BL_reg(context), EAX_reg(&realmode_ctx), EBX_reg(&realmode_ctx),
 299                 ECX_reg(&realmode_ctx), EDX_reg(&realmode_ctx));
 300           FIXME(int31,"      ESI=%08lx EDI=%08lx DS=%04lx ES=%04lx\n",
 301                 ESI_reg(&realmode_ctx), EDI_reg(&realmode_ctx),
 302                 DS_reg(&realmode_ctx), ES_reg(&realmode_ctx) );
 303         }
 304     }
 305     INT_SetRealModeContext( call, &realmode_ctx );
 306 }
 307
 308
 309 static void CallRMProcFar( CONTEXT *context )
 310 {
 311     REALMODECALL *p = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context), DI_reg(context) );
 312     CONTEXT context16;
 313     THDB *thdb = THREAD_Current();
 314     WORD argsize, sel;
 315     LPVOID addr;
 316     SEGPTR seg_addr;
 317
 318     TRACE(int31, "RealModeCall: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 319         p->eax, p->ebx, p->ecx, p->edx);
 320     TRACE(int31, "              ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x, %d WORD arguments\n",
 321         p->esi, p->edi, p->es, p->ds, p->cs, p->ip, CX_reg(context) );
 322
 323     if (!(p->cs) && !(p->ip)) { /* remove this check
 324                                    if Int21/6501 case map function
 325                                    has been implemented */
 326         SET_CFLAG(context);
 327         return;
 328     }
 329     INT_GetRealModeContext(p, &context16);
 330
 331 #if 0
 332     addr = DOSMEM_MapRealToLinear(MAKELONG(p->ip, p->cs));
 333     sel = SELECTOR_AllocBlock( addr, 0x10000, SEGMENT_CODE, FALSE, FALSE );
 334     seg_addr = PTR_SEG_OFF_TO_SEGPTR( sel, 0 );
 335
 336     CS_reg(&context16) = HIWORD(seg_addr);
 337     IP_reg(&context16) = LOWORD(seg_addr);
 338     EBP_reg(&context16) = OFFSETOF( thdb->cur_stack )
 339                                + (WORD)&((STACK16FRAME*)0)->bp;
 340
 341     argsize = CX_reg(context)*sizeof(WORD);
 342     memcpy( ((LPBYTE)THREAD_STACK16(thdb))-argsize,
 343     (LPBYTE)PTR_SEG_OFF_TO_LIN(SS_reg(context), SP_reg(context))+6, argsize );
 344
 345     Callbacks->CallRegisterShortProc(&context16, argsize);
 346
 347     UnMapLS(seg_addr);
 348 #else
 349     DPMI_CallRMProc( &context16, ((LPWORD)PTR_SEG_OFF_TO_LIN(SS_reg(context), SP_reg(context)))+3,
 350                      CX_reg(context), 0 );
 351 #endif
 352     INT_SetRealModeContext(p, &context16);
 353 }
 354
 355
 356 void WINAPI RMCallbackProc( FARPROC16 pmProc, REALMODECALL *rmc )
 357 {
 358     CONTEXT ctx;
 359     INT_GetRealModeContext(rmc, &ctx);
 360     Callbacks->CallRegisterShortProc(&ctx, 0);
 361 }
 362
 363
 364 static void AllocRMCB( CONTEXT *context )
 365 {
 366     RMCB *NewRMCB = HeapAlloc(GetProcessHeap(), 0, sizeof(RMCB));
 367     REALMODECALL *p = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context), DI_reg(context) );
 368     UINT16 uParagraph;
 369
 370     FIXME(int31, "EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n", p->eax, p->ebx, p->ecx, p->edx);
 371     FIXME(int31, "           ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x\n", p->esi, p->edi, p->es, p->ds, p->cs, p->ip);
 372     FIXME(int31, "           Function to call: %04x:%04x\n",
 373          (WORD)DS_reg(context), SI_reg(context) );
 374
 375     if (NewRMCB)
 376     {
 377         LPVOID RMCBmem = DOSMEM_GetBlock(0, 20, &uParagraph);
 378         LPBYTE p = RMCBmem;
 379
 380         *p++ = 0x68; /* pushl */
 381         *(FARPROC16 *)p =
 382         PTR_SEG_OFF_TO_LIN(ES_reg(context), SI_reg(context)); /* pmode proc to call */
 383         p+=4;
 384         *p++ = 0x68; /* pushl */
 385         *(LPVOID *)p =
 386         PTR_SEG_OFF_TO_LIN(ES_reg(context), DI_reg(context));
 387         p+=4;
 388         *p++ = 0x9a; /* lcall */
 389         *(FARPROC16 *)p = (FARPROC16)RMCallbackProc; /* FIXME ? */
 390         p+=4;
 391         GET_CS(*(WORD *)p);
 392         p+=2;
 393         *p++=0xc3; /* retf */
 394         NewRMCB->address = MAKELONG(0, uParagraph);
 395         NewRMCB->next = FirstRMCB;
 396         FirstRMCB = NewRMCB;
 397         CX_reg(context) = uParagraph;
 398         DX_reg(context) = 0;
 399     }
 400     else
 401     {
 402         AX_reg(context) = 0x8015; /* callback unavailable */
 403         SET_CFLAG(context);
 404     }
 405 }
 406
 407
 408 static void FreeRMCB( CONTEXT *context )
 409 {
 410     RMCB *CurrRMCB = FirstRMCB;
 411     RMCB *PrevRMCB = NULL;
 412
 413     FIXME(int31, "callback address: %04x:%04x\n",
 414           CX_reg(context), DX_reg(context));
 415
 416     while (CurrRMCB && (CurrRMCB->address != MAKELONG(DX_reg(context), CX_reg(context))))
 417     {
 418         PrevRMCB = CurrRMCB;
 419         CurrRMCB = CurrRMCB->next;
 420     }
 421     if (CurrRMCB)
 422     {
 423         if (PrevRMCB)
 424         PrevRMCB->next = CurrRMCB->next;
 425             else
 426         FirstRMCB = CurrRMCB->next;
 427         DOSMEM_FreeBlock(0, DOSMEM_MapRealToLinear(CurrRMCB->address));
 428         HeapFree(GetProcessHeap(), 0, CurrRMCB);
 429     }
 430     else
 431     {
 432         AX_reg(context) = 0x8024; /* invalid callback address */
 433         SET_CFLAG(context);
 434     }
 435 }
 436
 437 #ifdef MZ_SUPPORTED
 438 /* (see loader/dos/module.c, function MZ_InitDPMI) */
 439
 440 static void StartPM( CONTEXT *context, LPDOSTASK lpDosTask )
 441 {
 442     char *base = DOSMEM_MemoryBase(0);
 443     UINT16 cs, ss, ds, es;
 444     CONTEXT pm_ctx;
 445
 446     RESET_CFLAG(context);
 447     lpDosTask->dpmi_flag = AX_reg(context);
 448 /* our mode switch wrapper have placed the desired CS into DX */
 449     cs = SELECTOR_AllocBlock( base + (DWORD)(DX_reg(context)<<4), 0x10000, SEGMENT_CODE, FALSE, FALSE );
 450     ss = SELECTOR_AllocBlock( base + (DWORD)(SS_reg(context)<<4), 0x10000, SEGMENT_DATA, FALSE, FALSE );
 451     ds = SELECTOR_AllocBlock( base + (DWORD)(DS_reg(context)<<4), 0x10000, SEGMENT_DATA, FALSE, FALSE );
 452     es = SELECTOR_AllocBlock( base + (DWORD)(lpDosTask->psp_seg<<4), 0x100, SEGMENT_DATA, FALSE, FALSE );
 453
 454     pm_ctx = *context;
 455     CS_reg(&pm_ctx) = lpDosTask->dpmi_sel;
 456 /* our mode switch wrapper expects the new CS in DX, and the new SS in AX */
 457     AX_reg(&pm_ctx) = ss;
 458     DX_reg(&pm_ctx) = cs;
 459     DS_reg(&pm_ctx) = ds;
 460     ES_reg(&pm_ctx) = es;
 461     FS_reg(&pm_ctx) = 0;
 462     GS_reg(&pm_ctx) = 0;
 463
 464     TRACE(int31,"DOS program is now entering protected mode\n");
 465     Callbacks->CallRegisterShortProc(&pm_ctx, 0);
 466
 467     /* in the current state of affairs, we won't ever actually return here... */
 468
 469     UnMapLS(PTR_SEG_OFF_TO_SEGPTR(es,0));
 470     UnMapLS(PTR_SEG_OFF_TO_SEGPTR(ds,0));
 471     UnMapLS(PTR_SEG_OFF_TO_SEGPTR(ss,0));
 472     UnMapLS(PTR_SEG_OFF_TO_SEGPTR(cs,0));
 473 }
 474 #endif
 475
 476 /**********************************************************************
 477  *          INT_Int31Handler
 478  *
 479  * Handler for int 31h (DPMI).
 480  */
 481
 482 void WINAPI INT_Int31Handler( CONTEXT *context )
 483 {
 484     /*
 485      * Note: For Win32s processes, the whole linear address space is
 486      *       shifted by 0x10000 relative to the OS linear address space.
 487      *       See the comment in msdos/vxd.c.
 488      */
 489     DWORD offset = PROCESS_Current()->flags & PDB32_WIN32S_PROC ? 0x10000 : 0;
 490     #define AppToWine(addr) ((addr)? ((DWORD)(addr)) + offset : 0)
 491     #define WineToApp(addr) ((addr)? ((DWORD)(addr)) - offset : 0)
 492
 493     DWORD dw;
 494     BYTE *ptr;
 495
 496     TDB *pTask = (TDB *)GlobalLock16( GetCurrentTask() );
 497     NE_MODULE *pModule = pTask ? NE_GetPtr( pTask->hModule ) : NULL;
 498
 499     GlobalUnlock16( GetCurrentTask() );
 500
 501 #ifdef MZ_SUPPORTED
 502     if (ISV86(context) && pModule && pModule->lpDosTask) {
 503         /* Called from real mode, check if it's our wrapper */
 504         TRACE(int31,"called from real mode\n");
 505         if (CS_reg(context)==pModule->lpDosTask->dpmi_seg) {
 506             /* This is the protected mode switch */
 507             StartPM(context,pModule->lpDosTask);
 508             return;
 509         } else
 510         if (CS_reg(context)==pModule->lpDosTask->xms_seg) {
 511             /* This is the XMS driver entry point */
 512             XMS_Handler(context);
 513             return;
 514         }
 515     }
 516 #endif
 517
 518     RESET_CFLAG(context);
 519     switch(AX_reg(context))
 520     {
 521     case 0x0000:  /* Allocate LDT descriptors */
 522         TRACE(int31,"allocate LDT descriptors (%d)\n",CX_reg(context));
 523         if (!(AX_reg(context) = AllocSelectorArray( CX_reg(context) )))
 524         {
 525             TRACE(int31,"failed\n");
 526             AX_reg(context) = 0x8011;  /* descriptor unavailable */
 527             SET_CFLAG(context);
 528         }
 529         TRACE(int31,"success, array starts at 0x%04x\n",AX_reg(context));
 530         break;
 531
 532     case 0x0001:  /* Free LDT descriptor */
 533         TRACE(int31,"free LDT descriptor (0x%04x)\n",BX_reg(context));
 534         if (FreeSelector( BX_reg(context) ))
 535         {
 536             AX_reg(context) = 0x8022;  /* invalid selector */
 537             SET_CFLAG(context);
 538         }
 539         else
 540         {
 541             /* If a segment register contains the selector being freed, */
 542             /* set it to zero. */
 543             if (!((DS_reg(context)^BX_reg(context)) & ~3)) DS_reg(context) = 0;
 544             if (!((ES_reg(context)^BX_reg(context)) & ~3)) ES_reg(context) = 0;
 545             if (!((FS_reg(context)^BX_reg(context)) & ~3)) FS_reg(context) = 0;
 546             if (!((GS_reg(context)^BX_reg(context)) & ~3)) GS_reg(context) = 0;
 547         }
 548         break;
 549
 550     case 0x0002:  /* Real mode segment to descriptor */
 551         TRACE(int31,"real mode segment to descriptor (0x%04x)\n",BX_reg(context));
 552         {
 553             WORD entryPoint = 0;  /* KERNEL entry point for descriptor */
 554             switch(BX_reg(context))
 555             {
 556             case 0x0000: entryPoint = 183; break;  /* __0000H */
 557             case 0x0040: entryPoint = 193; break;  /* __0040H */
 558             case 0xa000: entryPoint = 174; break;  /* __A000H */
 559             case 0xb000: entryPoint = 181; break;  /* __B000H */
 560             case 0xb800: entryPoint = 182; break;  /* __B800H */
 561             case 0xc000: entryPoint = 195; break;  /* __C000H */
 562             case 0xd000: entryPoint = 179; break;  /* __D000H */
 563             case 0xe000: entryPoint = 190; break;  /* __E000H */
 564             case 0xf000: entryPoint = 194; break;  /* __F000H */
 565             default:
 566                 AX_reg(context) = DOSMEM_AllocSelector(BX_reg(context));
 567                 break;
 568             }
 569             if (entryPoint)
 570                 AX_reg(context) = LOWORD(NE_GetEntryPoint(
 571                                                  GetModuleHandle16( "KERNEL" ),
 572                                                  entryPoint ));
 573         }
 574         break;
 575
 576     case 0x0003:  /* Get next selector increment */
 577         TRACE(int31,"get selector increment (__AHINCR)\n");
 578         AX_reg(context) = __AHINCR;
 579         break;
 580
 581     case 0x0004:  /* Lock selector (not supported) */
 582         FIXME(int31,"lock selector not supported\n");
 583         AX_reg(context) = 0;  /* FIXME: is this a correct return value? */
 584         break;
 585
 586     case 0x0005:  /* Unlock selector (not supported) */
 587         FIXME(int31,"unlock selector not supported\n");
 588         AX_reg(context) = 0;  /* FIXME: is this a correct return value? */
 589         break;
 590
 591     case 0x0006:  /* Get selector base address */
 592         TRACE(int31,"get selector base address (0x%04x)\n",BX_reg(context));
 593         if (!(dw = GetSelectorBase( BX_reg(context) )))
 594         {
 595             AX_reg(context) = 0x8022;  /* invalid selector */
 596             SET_CFLAG(context);
 597         }
 598         else
 599         {
 600 #ifdef MZ_SUPPORTED
 601             if (pModule && pModule->lpDosTask) {
 602                 DWORD base = (DWORD)DOSMEM_MemoryBase(pModule->self);
 603                 if ((dw >= base) && (dw < base + 0x110000)) dw -= base;
 604             }
 605 #endif
 606             CX_reg(context) = HIWORD(WineToApp(dw));
 607             DX_reg(context) = LOWORD(WineToApp(dw));
 608         }
 609         break;
 610
 611     case 0x0007:  /* Set selector base address */
 612         TRACE(int31, "set selector base address (0x%04x,0x%08lx)\n",
 613                      BX_reg(context),
 614                      AppToWine(MAKELONG(DX_reg(context),CX_reg(context))));
 615         dw = AppToWine(MAKELONG(DX_reg(context), CX_reg(context)));
 616 #ifdef MZ_SUPPORTED
 617         /* well, what else could we possibly do? */
 618         if (pModule && pModule->lpDosTask) {
 619             if (dw < 0x110000) dw += (DWORD)DOSMEM_MemoryBase(pModule->self);
 620         }
 621 #endif
 622         SetSelectorBase(BX_reg(context), dw);
 623         break;
 624
 625     case 0x0008:  /* Set selector limit */
 626         TRACE(int31,"set selector limit (0x%04x,0x%08lx)\n",BX_reg(context),MAKELONG(DX_reg(context),CX_reg(context)));
 627         dw = MAKELONG( DX_reg(context), CX_reg(context) );
 628 #ifdef MZ_SUPPORTED
 629         if (pModule && pModule->lpDosTask) {
 630             DWORD base = GetSelectorBase( BX_reg(context) );
 631             if ((dw == 0xffffffff) || ((base < 0x110000) && (base + dw > 0x110000))) {
 632                 AX_reg(context) = 0x8021;  /* invalid value */
 633                 SET_CFLAG(context);
 634                 break;
 635             }
 636         }
 637 #endif
 638         SetSelectorLimit( BX_reg(context), dw );
 639         break;
 640
 641     case 0x0009:  /* Set selector access rights */
 642         TRACE(int31,"set selector access rights(0x%04x,0x%04x)\n",BX_reg(context),CX_reg(context));
 643         SelectorAccessRights( BX_reg(context), 1, CX_reg(context) );
 644         break;
 645
 646     case 0x000a:  /* Allocate selector alias */
 647         TRACE(int31,"allocate selector alias (0x%04x)\n",BX_reg(context));
 648         if (!(AX_reg(context) = AllocCStoDSAlias( BX_reg(context) )))
 649         {
 650             AX_reg(context) = 0x8011;  /* descriptor unavailable */
 651             SET_CFLAG(context);
 652         }
 653         break;
 654
 655     case 0x000b:  /* Get descriptor */
 656         TRACE(int31,"get descriptor (0x%04x)\n",BX_reg(context));
 657         {
 658             ldt_entry entry;
 659             LDT_GetEntry( SELECTOR_TO_ENTRY( BX_reg(context) ), &entry );
 660             entry.base = WineToApp(entry.base);
 661
 662             /* FIXME: should use ES:EDI for 32-bit clients */
 663             LDT_EntryToBytes( PTR_SEG_OFF_TO_LIN( ES_reg(context),
 664                                                   DI_reg(context) ), &entry );
 665         }
 666         break;
 667
 668     case 0x000c:  /* Set descriptor */
 669         TRACE(int31,"set descriptor (0x%04x)\n",BX_reg(context));
 670         {
 671             ldt_entry entry;
 672             LDT_BytesToEntry( PTR_SEG_OFF_TO_LIN( ES_reg(context),
 673                                                   DI_reg(context) ), &entry );
 674             entry.base = AppToWine(entry.base);
 675
 676             LDT_SetEntry( SELECTOR_TO_ENTRY( BX_reg(context) ), &entry );
 677         }
 678         break;
 679
 680     case 0x000d:  /* Allocate specific LDT descriptor */
 681         FIXME(int31,"allocate descriptor (0x%04x), stub!\n",BX_reg(context));
 682         AX_reg(context) = 0x8011; /* descriptor unavailable */
 683         SET_CFLAG(context);
 684         break;
 685     case 0x0100:  /* Allocate DOS memory block */
 686         TRACE(int31,"allocate DOS memory block (0x%x paragraphs)\n",BX_reg(context));
 687         dw = GlobalDOSAlloc((DWORD)BX_reg(context)<<4);
 688         if (dw) {
 689             AX_reg(context) = HIWORD(dw);
 690             DX_reg(context) = LOWORD(dw);
 691         } else {
 692             AX_reg(context) = 0x0008; /* insufficient memory */
 693             BX_reg(context) = DOSMEM_Available(0)>>4;
 694             SET_CFLAG(context);
 695         }
 696         break;
 697     case 0x0101:  /* Free DOS memory block */
 698         TRACE(int31,"free DOS memory block (0x%04x)\n",DX_reg(context));
 699         dw = GlobalDOSFree(DX_reg(context));
 700         if (!dw) {
 701             AX_reg(context) = 0x0009; /* memory block address invalid */
 702             SET_CFLAG(context);
 703         }
 704         break;
 705     case 0x0200: /* get real mode interrupt vector */
 706         FIXME(int31,"get realmode interupt vector(0x%02x) unimplemented.\n",
 707               BL_reg(context));
 708         SET_CFLAG(context);
 709         break;
 710     case 0x0201: /* set real mode interrupt vector */
 711         FIXME(int31, "set realmode interupt vector(0x%02x,0x%04x:0x%04x) unimplemented\n", BL_reg(context),CX_reg(context),DX_reg(context));
 712         SET_CFLAG(context);
 713         break;
 714     case 0x0204:  /* Get protected mode interrupt vector */
 715         TRACE(int31,"get protected mode interrupt handler (0x%02x), stub!\n",BL_reg(context));
 716         dw = (DWORD)INT_GetPMHandler( BL_reg(context) );
 717         CX_reg(context) = HIWORD(dw);
 718         DX_reg(context) = LOWORD(dw);
 719         break;
 720
 721     case 0x0205:  /* Set protected mode interrupt vector */
 722         TRACE(int31,"set protected mode interrupt handler (0x%02x,%p), stub!\n",
 723             BL_reg(context),PTR_SEG_OFF_TO_LIN(CX_reg(context),DX_reg(context)));
 724         INT_SetPMHandler( BL_reg(context),
 725                           (FARPROC16)PTR_SEG_OFF_TO_SEGPTR( CX_reg(context),
 726                                                             DX_reg(context) ));
 727         break;
 728
 729     case 0x0300:  /* Simulate real mode interrupt */
 730         INT_DoRealModeInt( context );
 731         break;
 732
 733     case 0x0301:  /* Call real mode procedure with far return */
 734         CallRMProcFar( context );
 735         break;
 736
 737     case 0x0302:  /* Call real mode procedure with interrupt return */
 738         {
 739             REALMODECALL *p = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context), DI_reg(context) );
 740             FIXME(int31, "RealModeCallIret: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n", p->eax, p->ebx, p->ecx, p->edx);
 741             FIXME(int31, "                  ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x\n", p->esi, p->edi, p->es, p->ds, p->cs, p->ip );
 742             SET_CFLAG(context);
 743         }
 744         break;
 745
 746     case 0x0303:  /* Allocate Real Mode Callback Address */
 747         AllocRMCB( context );
 748         break;
 749
 750     case 0x0304:  /* Free Real Mode Callback Address */
 751         FreeRMCB( context );
 752         break;
 753
 754     case 0x0400:  /* Get DPMI version */
 755         TRACE(int31,"get DPMI version\n");
 756         {
 757             SYSTEM_INFO si;
 758
 759             GetSystemInfo(&si);
 760             AX_reg(context) = 0x005a;  /* DPMI version 0.90 */
 761             BX_reg(context) = 0x0005;  /* Flags: 32-bit, virtual memory */
 762             CL_reg(context) = si.wProcessorLevel;
 763             DX_reg(context) = 0x0102;  /* Master/slave interrupt controller base*/
 764             break;
 765         }
 766     case 0x0500:  /* Get free memory information */
 767         TRACE(int31,"get free memory information\n");
 768         {
 769             MEMMANINFO mmi;
 770
 771             mmi.dwSize = sizeof(mmi);
 772             MemManInfo(&mmi);
 773             ptr = (BYTE *)PTR_SEG_OFF_TO_LIN(ES_reg(context),DI_reg(context));
 774             /* the layout is just the same as MEMMANINFO, but without
 775              * the dwSize entry.
 776              */
 777             memcpy(ptr,((char*)&mmi)+4,sizeof(mmi)-4);
 778             break;
 779         }
 780     case 0x0501:  /* Allocate memory block */
 781         TRACE(int31,"allocate memory block (%ld)\n",MAKELONG(CX_reg(context),BX_reg(context)));
 782         if (!(ptr = (BYTE *)DPMI_xalloc(MAKELONG(CX_reg(context), BX_reg(context)))))
 783         {
 784             AX_reg(context) = 0x8012;  /* linear memory not available */
 785             SET_CFLAG(context);
 786         } else {
 787             BX_reg(context) = SI_reg(context) = HIWORD(WineToApp(ptr));
 788             CX_reg(context) = DI_reg(context) = LOWORD(WineToApp(ptr));
 789         }
 790         break;
 791
 792     case 0x0502:  /* Free memory block */
 793         TRACE(int31, "free memory block (0x%08lx)\n",
 794                      AppToWine(MAKELONG(DI_reg(context),SI_reg(context))));
 795         DPMI_xfree( (void *)AppToWine(MAKELONG(DI_reg(context),
 796                                                SI_reg(context))) );
 797         break;
 798
 799     case 0x0503:  /* Resize memory block */
 800         TRACE(int31, "resize memory block (0x%08lx,%ld)\n",
 801                      AppToWine(MAKELONG(DI_reg(context),SI_reg(context))),
 802                      MAKELONG(CX_reg(context),BX_reg(context)));
 803         if (!(ptr = (BYTE *)DPMI_xrealloc(
 804                 (void *)AppToWine(MAKELONG(DI_reg(context),SI_reg(context))),
 805                 MAKELONG(CX_reg(context),BX_reg(context)))))
 806         {
 807             AX_reg(context) = 0x8012;  /* linear memory not available */
 808             SET_CFLAG(context);
 809         } else {
 810             BX_reg(context) = SI_reg(context) = HIWORD(WineToApp(ptr));
 811             CX_reg(context) = DI_reg(context) = LOWORD(WineToApp(ptr));
 812         }
 813         break;
 814
 815     case 0x0507:  /* Modify page attributes */
 816         FIXME(int31,"modify page attributes unimplemented\n");
 817         break;  /* Just ignore it */
 818
 819     case 0x0600:  /* Lock linear region */
 820         FIXME(int31,"lock linear region unimplemented\n");
 821         break;  /* Just ignore it */
 822
 823     case 0x0601:  /* Unlock linear region */
 824         FIXME(int31,"unlock linear region unimplemented\n");
 825         break;  /* Just ignore it */
 826
 827     case 0x0602:  /* Unlock real-mode region */
 828         FIXME(int31,"unlock realmode region unimplemented\n");
 829         break;  /* Just ignore it */
 830
 831     case 0x0603:  /* Lock real-mode region */
 832         FIXME(int31,"lock realmode region unimplemented\n");
 833         break;  /* Just ignore it */
 834
 835     case 0x0604:  /* Get page size */
 836         TRACE(int31,"get pagesize\n");
 837         BX_reg(context) = 0;
 838         CX_reg(context) = VIRTUAL_GetPageSize();
 839         break;
 840
 841     case 0x0702:  /* Mark page as demand-paging candidate */
 842         FIXME(int31,"mark page as demand-paging candidate\n");
 843         break;  /* Just ignore it */
 844
 845     case 0x0703:  /* Discard page contents */
 846         FIXME(int31,"discard page contents\n");
 847         break;  /* Just ignore it */
 848
 849      case 0x0800:  /* Physical address mapping */
 850         FIXME(int31,"map real to linear (0x%08lx)\n",MAKELONG(CX_reg(context),BX_reg(context)));
 851          if(!(ptr=DOSMEM_MapRealToLinear(MAKELONG(CX_reg(context),BX_reg(context)))))
 852          {
 853              AX_reg(context) = 0x8021;
 854              SET_CFLAG(context);
 855          }
 856          else
 857          {
 858              BX_reg(context) = HIWORD(WineToApp(ptr));
 859              CX_reg(context) = LOWORD(WineToApp(ptr));
 860              RESET_CFLAG(context);
 861          }
 862          break;
 863
 864     default:
 865         INT_BARF( context, 0x31 );
 866         AX_reg(context) = 0x8001;  /* unsupported function */
 867         SET_CFLAG(context);
 868         break;
 869     }
 870
 871     #undef AppToWine
 872     #undef WineToApp
 873 }