dlls/winedos/module.c

   1 /*
   2  * DOS (MZ) loader
   3  *
   4  * Copyright 1998 Ove Kåven
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  * Note: This code hasn't been completely cleaned up yet.
  21  */
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25
  26 #include <stdarg.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <fcntl.h>
  31 #include <signal.h>
  32 #ifdef HAVE_UNISTD_H
  33 # include <unistd.h>
  34 #endif
  35 #include <sys/types.h>
  36 #include <sys/stat.h>
  37 #ifdef HAVE_SYS_TIME_H
  38 # include <sys/time.h>
  39 #endif
  40 #include "windef.h"
  41 #include "winbase.h"
  42 #include "wine/winbase16.h"
  43 #include "wingdi.h"
  44 #include "winuser.h"
  45 #include "winerror.h"
  46 #include "wine/debug.h"
  47 #include "dosexe.h"
  48 #include "dosvm.h"
  49 #include "vga.h"
  50
  51 WINE_DEFAULT_DEBUG_CHANNEL(module);
  52
  53 static BOOL DOSVM_isdosexe;
  54
  55 /**********************************************************************
  56  *          DOSVM_IsWin16
  57  *
  58  * Return TRUE if we are in Windows process.
  59  */
  60 BOOL DOSVM_IsWin16(void)
  61 {
  62   return DOSVM_isdosexe ? FALSE : TRUE;
  63 }
  64
  65 #ifdef MZ_SUPPORTED
  66
  67 #ifdef HAVE_SYS_MMAN_H
  68 # include <sys/mman.h>
  69 #endif
  70
  71 /* define this to try mapping through /proc/pid/mem instead of a temp file,
  72    but Linus doesn't like mmapping /proc/pid/mem, so it doesn't work for me */
  73 #undef MZ_MAPSELF
  74
  75 #define BIOS_DATA_SEGMENT 0x40
  76 #define PSP_SIZE 0x10
  77
  78 #define SEG16(ptr,seg) ((LPVOID)((BYTE*)ptr+((DWORD)(seg)<<4)))
  79 #define SEGPTR16(ptr,segptr) ((LPVOID)((BYTE*)ptr+((DWORD)SELECTOROF(segptr)<<4)+OFFSETOF(segptr)))
  80
  81 /* structures for EXEC */
  82
  83 typedef struct {
  84   WORD env_seg;
  85   DWORD cmdline WINE_PACKED;
  86   DWORD fcb1 WINE_PACKED;
  87   DWORD fcb2 WINE_PACKED;
  88   WORD init_sp;
  89   WORD init_ss;
  90   WORD init_ip;
  91   WORD init_cs;
  92 } ExecBlock;
  93
  94 typedef struct {
  95   WORD load_seg;
  96   WORD rel_seg;
  97 } OverlayBlock;
  98
  99 /* global variables */
 100
 101 pid_t dosvm_pid;
 102
 103 static WORD init_cs,init_ip,init_ss,init_sp;
 104 static HANDLE dosvm_thread, loop_thread;
 105 static DWORD dosvm_tid, loop_tid;
 106
 107 static void MZ_Launch( LPCSTR cmdtail, int length );
 108 static BOOL MZ_InitTask(void);
 109
 110 static void MZ_CreatePSP( LPVOID lpPSP, WORD env, WORD par )
 111 {
 112   PDB16*psp=lpPSP;
 113
 114   psp->int20=0x20CD; /* int 20 */
 115   /* some programs use this to calculate how much memory they need */
 116   psp->nextParagraph=0x9FFF; /* FIXME: use a real value */
 117   /* FIXME: dispatcher */
 118   psp->savedint22 = DOSVM_GetRMHandler(0x22);
 119   psp->savedint23 = DOSVM_GetRMHandler(0x23);
 120   psp->savedint24 = DOSVM_GetRMHandler(0x24);
 121   psp->parentPSP=par;
 122   psp->environment=env;
 123   /* FIXME: more PSP stuff */
 124 }
 125
 126 static void MZ_FillPSP( LPVOID lpPSP, LPCSTR cmdtail, int length )
 127 {
 128     PDB16 *psp = lpPSP;
 129
 130     if(length > 127)
 131     {
 132         WARN( "Command tail truncated! (length %d)\n", length );
 133         length = 126;
 134     }
 135
 136     psp->cmdLine[0] = length;
 137
 138     /*
 139      * Length of exactly 127 bytes means that full command line is
 140      * stored in environment variable CMDLINE and PSP contains
 141      * command tail truncated to 126 bytes.
 142      */
 143     if(length == 127)
 144         length = 126;
 145
 146     if(length > 0)
 147         memmove(psp->cmdLine+1, cmdtail, length);
 148
 149     psp->cmdLine[length+1] = '\r';
 150
 151     /* FIXME: more PSP stuff */
 152 }
 153
 154 static WORD MZ_InitEnvironment( LPCSTR env, LPCSTR name )
 155 {
 156  unsigned sz=0;
 157  WORD seg;
 158  LPSTR envblk;
 159
 160  if (env) {
 161   /* get size of environment block */
 162   while (env[sz++]) sz+=strlen(env+sz)+1;
 163  } else sz++;
 164  /* allocate it */
 165  envblk=DOSMEM_GetBlock(sz+sizeof(WORD)+strlen(name)+1,&seg);
 166  /* fill it */
 167  if (env) {
 168   memcpy(envblk,env,sz);
 169  } else envblk[0]=0;
 170  /* DOS 3.x: the block contains 1 additional string */
 171  *(WORD*)(envblk+sz)=1;
 172  /* being the program name itself */
 173  strcpy(envblk+sz+sizeof(WORD),name);
 174  return seg;
 175 }
 176
 177 static BOOL MZ_InitMemory(void)
 178 {
 179     /* initialize the memory */
 180     TRACE("Initializing DOS memory structures\n");
 181     DOSMEM_Init(TRUE);
 182     DOSDEV_InstallDOSDevices();
 183
 184     return TRUE;
 185 }
 186
 187 static BOOL MZ_DoLoadImage( HANDLE hFile, LPCSTR filename, OverlayBlock *oblk )
 188 {
 189   IMAGE_DOS_HEADER mz_header;
 190   DWORD image_start,image_size,min_size,max_size,avail;
 191   BYTE*psp_start,*load_start,*oldenv;
 192   int x, old_com=0, alloc;
 193   SEGPTR reloc;
 194   WORD env_seg, load_seg, rel_seg, oldpsp_seg;
 195   DWORD len;
 196
 197   if (DOSVM_psp) {
 198     /* DOS process already running, inherit from it */
 199     PDB16* par_psp = (PDB16*)((DWORD)DOSVM_psp << 4);
 200     alloc=0;
 201     oldenv = (LPBYTE)((DWORD)par_psp->environment << 4);
 202     oldpsp_seg = DOSVM_psp;
 203   } else {
 204     /* allocate new DOS process, inheriting from Wine environment */
 205     alloc=1;
 206     oldenv = GetEnvironmentStringsA();
 207     oldpsp_seg = 0;
 208   }
 209
 210  SetFilePointer(hFile,0,NULL,FILE_BEGIN);
 211  if (   !ReadFile(hFile,&mz_header,sizeof(mz_header),&len,NULL)
 212      || len != sizeof(mz_header)
 213      || mz_header.e_magic != IMAGE_DOS_SIGNATURE) {
 214   char *p = strrchr( filename, '.' );
 215   if (!p || strcasecmp( p, ".com" ))  /* check for .COM extension */
 216   {
 217       SetLastError(ERROR_BAD_FORMAT);
 218       goto load_error;
 219   }
 220   old_com=1; /* assume .COM file */
 221   image_start=0;
 222   image_size=GetFileSize(hFile,NULL);
 223   min_size=0x10000; max_size=0x100000;
 224   mz_header.e_crlc=0;
 225   mz_header.e_ss=0; mz_header.e_sp=0xFFFE;
 226   mz_header.e_cs=0; mz_header.e_ip=0x100;
 227  } else {
 228   /* calculate load size */
 229   image_start=mz_header.e_cparhdr<<4;
 230   image_size=mz_header.e_cp<<9; /* pages are 512 bytes */
 231   if ((mz_header.e_cblp!=0)&&(mz_header.e_cblp!=4)) image_size-=512-mz_header.e_cblp;
 232   image_size-=image_start;
 233   min_size=image_size+((DWORD)mz_header.e_minalloc<<4)+(PSP_SIZE<<4);
 234   max_size=image_size+((DWORD)mz_header.e_maxalloc<<4)+(PSP_SIZE<<4);
 235  }
 236
 237   if (alloc) MZ_InitMemory();
 238
 239   if (oblk) {
 240     /* load overlay into preallocated memory */
 241     load_seg=oblk->load_seg;
 242     rel_seg=oblk->rel_seg;
 243     load_start=(LPBYTE)((DWORD)load_seg<<4);
 244   } else {
 245     /* allocate environment block */
 246     env_seg=MZ_InitEnvironment(oldenv, filename);
 247
 248     /* allocate memory for the executable */
 249     TRACE("Allocating DOS memory (min=%ld, max=%ld)\n",min_size,max_size);
 250     avail=DOSMEM_Available();
 251     if (avail<min_size) {
 252       ERR("insufficient DOS memory\n");
 253       SetLastError(ERROR_NOT_ENOUGH_MEMORY);
 254       goto load_error;
 255     }
 256     if (avail>max_size) avail=max_size;
 257     psp_start=DOSMEM_GetBlock(avail,&DOSVM_psp);
 258     if (!psp_start) {
 259       ERR("error allocating DOS memory\n");
 260       SetLastError(ERROR_NOT_ENOUGH_MEMORY);
 261       goto load_error;
 262     }
 263     load_seg=DOSVM_psp+(old_com?0:PSP_SIZE);
 264     rel_seg=load_seg;
 265     load_start=psp_start+(PSP_SIZE<<4);
 266     MZ_CreatePSP(psp_start, env_seg, oldpsp_seg);
 267   }
 268
 269  /* load executable image */
 270  TRACE("loading DOS %s image, %08lx bytes\n",old_com?"COM":"EXE",image_size);
 271  SetFilePointer(hFile,image_start,NULL,FILE_BEGIN);
 272  if (!ReadFile(hFile,load_start,image_size,&len,NULL) || len != image_size) {
 273   SetLastError(ERROR_BAD_FORMAT);
 274   goto load_error;
 275  }
 276
 277  if (mz_header.e_crlc) {
 278   /* load relocation table */
 279   TRACE("loading DOS EXE relocation table, %d entries\n",mz_header.e_crlc);
 280   /* FIXME: is this too slow without read buffering? */
 281   SetFilePointer(hFile,mz_header.e_lfarlc,NULL,FILE_BEGIN);
 282   for (x=0; x<mz_header.e_crlc; x++) {
 283    if (!ReadFile(hFile,&reloc,sizeof(reloc),&len,NULL) || len != sizeof(reloc)) {
 284     SetLastError(ERROR_BAD_FORMAT);
 285     goto load_error;
 286    }
 287    *(WORD*)SEGPTR16(load_start,reloc)+=rel_seg;
 288   }
 289  }
 290
 291   if (!oblk) {
 292     init_cs = load_seg+mz_header.e_cs;
 293     init_ip = mz_header.e_ip;
 294     init_ss = load_seg+mz_header.e_ss;
 295     init_sp = mz_header.e_sp;
 296
 297     TRACE("entry point: %04x:%04x\n",init_cs,init_ip);
 298   }
 299
 300   if (alloc && !MZ_InitTask()) {
 301     SetLastError(ERROR_GEN_FAILURE);
 302     return FALSE;
 303   }
 304
 305   return TRUE;
 306
 307 load_error:
 308   DOSVM_psp = oldpsp_seg;
 309
 310   return FALSE;
 311 }
 312
 313 /***********************************************************************
 314  *              wine_load_dos_exe (WINEDOS.@)
 315  *
 316  * Called from WineVDM when a new real-mode DOS process is started.
 317  * Loads DOS program into memory and executes the program.
 318  */
 319 void WINAPI wine_load_dos_exe( LPCSTR filename, LPCSTR cmdline )
 320 {
 321     char dos_cmdtail[126];
 322     int  dos_length = 0;
 323
 324     HANDLE hFile = CreateFileA( filename, GENERIC_READ, FILE_SHARE_READ,
 325                                 NULL, OPEN_EXISTING, 0, 0 );
 326     if (hFile == INVALID_HANDLE_VALUE) return;
 327     DOSVM_isdosexe = TRUE;
 328
 329     if(cmdline && *cmdline)
 330     {
 331         dos_length = strlen(cmdline);
 332         memmove( dos_cmdtail + 1, cmdline,
 333                  (dos_length < 125) ? dos_length : 125 );
 334
 335         /* Non-empty command tail always starts with at least one space. */
 336         dos_cmdtail[0] = ' ';
 337         dos_length++;
 338
 339         /*
 340          * If command tail is longer than 126 characters,
 341          * set tail length to 127 and fill CMDLINE environment variable
 342          * with full command line (this includes filename).
 343          */
 344         if (dos_length > 126)
 345         {
 346             char *cmd = HeapAlloc( GetProcessHeap(), 0,
 347                                    dos_length + strlen(filename) + 4 );
 348             char *ptr = cmd;
 349
 350             if (!cmd)
 351                 return;
 352
 353             /*
 354              * Append filename. If path includes spaces, quote the path.
 355              */
 356             if (strchr(filename, ' '))
 357             {
 358                 *ptr++ = '\"';
 359                 strcpy( ptr, filename );
 360                 ptr += strlen(filename);
 361                 *ptr++ = '\"';
 362             }
 363             else
 364             {
 365                 strcpy( ptr, filename );
 366                 ptr += strlen(filename);
 367             }
 368
 369             /*
 370              * Append command tail.
 371              */
 372             if (cmdline[0] != ' ')
 373                 *ptr++ = ' ';
 374             strcpy( ptr, cmdline );
 375
 376             /*
 377              * Set environment variable. This will be passed to
 378              * new DOS process.
 379              */
 380             if (!SetEnvironmentVariableA( "CMDLINE", cmd ))
 381             {
 382                 HeapFree(GetProcessHeap(), 0, cmd );
 383                 return;
 384             }
 385
 386             HeapFree(GetProcessHeap(), 0, cmd );
 387             dos_length = 127;
 388         }
 389     }
 390
 391     if (MZ_DoLoadImage( hFile, filename, NULL ))
 392         MZ_Launch( dos_cmdtail, dos_length );
 393 }
 394
 395 /***********************************************************************
 396  *              MZ_Exec
 397  *
 398  * this may only be called from existing DOS processes
 399  */
 400 BOOL WINAPI MZ_Exec( CONTEXT86 *context, LPCSTR filename, BYTE func, LPVOID paramblk )
 401 {
 402   DWORD binType;
 403   STARTUPINFOA st;
 404   PROCESS_INFORMATION pe;
 405   HANDLE hFile;
 406
 407   BOOL ret = FALSE;
 408
 409   if(!GetBinaryTypeA(filename, &binType))   /* determine what kind of binary this is */
 410   {
 411     return FALSE; /* binary is not an executable */
 412   }
 413
 414   /* handle non-dos executables */
 415   if(binType != SCS_DOS_BINARY)
 416   {
 417     if(func == 0) /* load and execute */
 418     {
 419       LPBYTE fullCmdLine;
 420       WORD fullCmdLength;
 421       LPBYTE psp_start = (LPBYTE)((DWORD)DOSVM_psp << 4);
 422       PDB16 *psp = (PDB16 *)psp_start;
 423       ExecBlock *blk = (ExecBlock *)paramblk;
 424       LPBYTE cmdline = PTR_REAL_TO_LIN(SELECTOROF(blk->cmdline),OFFSETOF(blk->cmdline));
 425       LPBYTE envblock = PTR_REAL_TO_LIN(psp->environment, 0);
 426       int    cmdLength = cmdline[0];
 427
 428       /*
 429        * If cmdLength is 127, command tail is truncated and environment
 430        * variable CMDLINE should contain full command line
 431        * (this includes filename).
 432        */
 433       if (cmdLength == 127)
 434       {
 435           FIXME( "CMDLINE argument passing is unimplemented.\n" );
 436           cmdLength = 126; /* FIXME */
 437       }
 438
 439       fullCmdLength = (strlen(filename) + 1) + cmdLength + 1; /* filename + space + cmdline + terminating null character */
 440
 441       fullCmdLine = HeapAlloc(GetProcessHeap(), 0, fullCmdLength);
 442       if(!fullCmdLine) return FALSE; /* return false on memory alloc failure */
 443
 444       /* build the full command line from the executable file and the command line being passed in */
 445       snprintf(fullCmdLine, fullCmdLength, "%s ", filename); /* start off with the executable filename and a space */
 446       memcpy(fullCmdLine + strlen(fullCmdLine), cmdline + 1, cmdLength); /* append cmdline onto the end */
 447       fullCmdLine[fullCmdLength - 1] = 0; /* null terminate string */
 448
 449       ZeroMemory (&st, sizeof(STARTUPINFOA));
 450       st.cb = sizeof(STARTUPINFOA);
 451       ret = CreateProcessA (NULL, fullCmdLine, NULL, NULL, TRUE, 0, envblock, NULL, &st, &pe);
 452
 453       /* wait for the app to finish and clean up PROCESS_INFORMATION handles */
 454       if(ret)
 455       {
 456         WaitForSingleObject(pe.hProcess, INFINITE);  /* wait here until the child process is complete */
 457         CloseHandle(pe.hProcess);
 458         CloseHandle(pe.hThread);
 459       }
 460
 461       HeapFree(GetProcessHeap(), 0, fullCmdLine);  /* free the memory we allocated */
 462     }
 463     else
 464     {
 465       FIXME("EXEC type of %d not implemented for non-dos executables\n", func);
 466       ret = FALSE;
 467     }
 468
 469     return ret;
 470   } /* if(binType != SCS_DOS_BINARY) */
 471
 472
 473   /* handle dos executables */
 474
 475   hFile = CreateFileA( filename, GENERIC_READ, FILE_SHARE_READ,
 476                              NULL, OPEN_EXISTING, 0, 0);
 477   if (hFile == INVALID_HANDLE_VALUE) return FALSE;
 478
 479   switch (func) {
 480   case 0: /* load and execute */
 481   case 1: /* load but don't execute */
 482     {
 483       /* save current process's return SS:SP now */
 484       LPBYTE psp_start = (LPBYTE)((DWORD)DOSVM_psp << 4);
 485       PDB16 *psp = (PDB16 *)psp_start;
 486       psp->saveStack = (DWORD)MAKESEGPTR(context->SegSs, LOWORD(context->Esp));
 487     }
 488     ret = MZ_DoLoadImage( hFile, filename, NULL );
 489     if (ret) {
 490       /* MZ_LoadImage created a new PSP and loaded new values into it,
 491        * let's work on the new values now */
 492       LPBYTE psp_start = (LPBYTE)((DWORD)DOSVM_psp << 4);
 493       ExecBlock *blk = (ExecBlock *)paramblk;
 494       LPBYTE cmdline = PTR_REAL_TO_LIN(SELECTOROF(blk->cmdline),OFFSETOF(blk->cmdline));
 495
 496       /* First character contains the length of the command line. */
 497       MZ_FillPSP(psp_start, cmdline + 1, cmdline[0]);
 498
 499       /* the lame MS-DOS engineers decided that the return address should be in int22 */
 500       DOSVM_SetRMHandler(0x22, (FARPROC16)MAKESEGPTR(context->SegCs, LOWORD(context->Eip)));
 501       if (func) {
 502         /* don't execute, just return startup state */
 503         blk->init_cs = init_cs;
 504         blk->init_ip = init_ip;
 505         blk->init_ss = init_ss;
 506         blk->init_sp = init_sp;
 507       } else {
 508         /* execute by making us return to new process */
 509         context->SegCs = init_cs;
 510         context->Eip   = init_ip;
 511         context->SegSs = init_ss;
 512         context->Esp   = init_sp;
 513         context->SegDs = DOSVM_psp;
 514         context->SegEs = DOSVM_psp;
 515         context->Eax   = 0;
 516       }
 517     }
 518     break;
 519   case 3: /* load overlay */
 520     {
 521       OverlayBlock *blk = (OverlayBlock *)paramblk;
 522       ret = MZ_DoLoadImage( hFile, filename, blk );
 523     }
 524     break;
 525   default:
 526     FIXME("EXEC load type %d not implemented\n", func);
 527     SetLastError(ERROR_INVALID_FUNCTION);
 528     break;
 529   }
 530   CloseHandle(hFile);
 531   return ret;
 532 }
 533
 534 /***********************************************************************
 535  *              MZ_AllocDPMITask
 536  */
 537 void WINAPI MZ_AllocDPMITask( void )
 538 {
 539   MZ_InitMemory();
 540   MZ_InitTask();
 541 }
 542
 543 /***********************************************************************
 544  *              MZ_RunInThread
 545  */
 546 void WINAPI MZ_RunInThread( PAPCFUNC proc, ULONG_PTR arg )
 547 {
 548   if (loop_thread) {
 549     DOS_SPC spc;
 550     HANDLE event;
 551
 552     spc.proc = proc;
 553     spc.arg = arg;
 554     event = CreateEventA(NULL, TRUE, FALSE, NULL);
 555     PostThreadMessageA(loop_tid, WM_USER, (WPARAM)event, (LPARAM)&spc);
 556     WaitForSingleObject(event, INFINITE);
 557     CloseHandle(event);
 558   } else
 559     proc(arg);
 560 }
 561
 562 static DWORD WINAPI MZ_DOSVM( LPVOID lpExtra )
 563 {
 564   CONTEXT context;
 565   DWORD ret;
 566
 567   dosvm_pid = getpid();
 568
 569   memset( &context, 0, sizeof(context) );
 570   context.SegCs  = init_cs;
 571   context.Eip    = init_ip;
 572   context.SegSs  = init_ss;
 573   context.Esp    = init_sp;
 574   context.SegDs  = DOSVM_psp;
 575   context.SegEs  = DOSVM_psp;
 576   context.EFlags = V86_FLAG | VIF_MASK;
 577   DOSVM_SetTimer(0x10000);
 578   ret = DOSVM_Enter( &context );
 579
 580   dosvm_pid = 0;
 581   return ret;
 582 }
 583
 584 static BOOL MZ_InitTask(void)
 585 {
 586   if (!DuplicateHandle(GetCurrentProcess(), GetCurrentThread(),
 587                        GetCurrentProcess(), &loop_thread,
 588                        0, FALSE, DUPLICATE_SAME_ACCESS))
 589     return FALSE;
 590   dosvm_thread = CreateThread(NULL, 0, MZ_DOSVM, NULL, CREATE_SUSPENDED, &dosvm_tid);
 591   if (!dosvm_thread) {
 592     CloseHandle(loop_thread);
 593     loop_thread = 0;
 594     return FALSE;
 595   }
 596   loop_tid = GetCurrentThreadId();
 597   return TRUE;
 598 }
 599
 600 static void MZ_Launch( LPCSTR cmdtail, int length )
 601 {
 602   TDB *pTask = GlobalLock16( GetCurrentTask() );
 603   BYTE *psp_start = PTR_REAL_TO_LIN( DOSVM_psp, 0 );
 604   DWORD rv;
 605   SYSLEVEL *lock;
 606
 607   MZ_FillPSP(psp_start, cmdtail, length);
 608   pTask->flags |= TDBF_WINOLDAP;
 609
 610   /* DTA is set to PSP:0080h when a program is started. */
 611   pTask->dta = MAKESEGPTR( DOSVM_psp, 0x80 );
 612
 613   GetpWin16Lock( &lock );
 614   _LeaveSysLevel( lock );
 615
 616   ResumeThread(dosvm_thread);
 617   rv = DOSVM_Loop(dosvm_thread);
 618
 619   CloseHandle(dosvm_thread);
 620   dosvm_thread = 0; dosvm_tid = 0;
 621   CloseHandle(loop_thread);
 622   loop_thread = 0; loop_tid = 0;
 623
 624   VGA_Clean();
 625   ExitProcess(rv);
 626 }
 627
 628 /***********************************************************************
 629  *              MZ_Exit
 630  */
 631 void WINAPI MZ_Exit( CONTEXT86 *context, BOOL cs_psp, WORD retval )
 632 {
 633   if (DOSVM_psp) {
 634     WORD psp_seg = cs_psp ? context->SegCs : DOSVM_psp;
 635     LPBYTE psp_start = (LPBYTE)((DWORD)psp_seg << 4);
 636     PDB16 *psp = (PDB16 *)psp_start;
 637     WORD parpsp = psp->parentPSP; /* check for parent DOS process */
 638     if (parpsp) {
 639       /* retrieve parent's return address */
 640       FARPROC16 retaddr = DOSVM_GetRMHandler(0x22);
 641       /* restore interrupts */
 642       DOSVM_SetRMHandler(0x22, psp->savedint22);
 643       DOSVM_SetRMHandler(0x23, psp->savedint23);
 644       DOSVM_SetRMHandler(0x24, psp->savedint24);
 645       /* FIXME: deallocate file handles etc */
 646       /* free process's associated memory
 647        * FIXME: walk memory and deallocate all blocks owned by process */
 648       DOSMEM_FreeBlock( PTR_REAL_TO_LIN(psp->environment,0) );
 649       DOSMEM_FreeBlock( PTR_REAL_TO_LIN(DOSVM_psp,0) );
 650       /* switch to parent's PSP */
 651       DOSVM_psp = parpsp;
 652       psp_start = (LPBYTE)((DWORD)parpsp << 4);
 653       psp = (PDB16 *)psp_start;
 654       /* now return to parent */
 655       DOSVM_retval = retval;
 656       context->SegCs = SELECTOROF(retaddr);
 657       context->Eip   = OFFSETOF(retaddr);
 658       context->SegSs = SELECTOROF(psp->saveStack);
 659       context->Esp   = OFFSETOF(psp->saveStack);
 660       return;
 661     } else
 662       TRACE("killing DOS task\n");
 663   }
 664   ExitThread( retval );
 665 }
 666
 667
 668 /***********************************************************************
 669  *              MZ_Current
 670  */
 671 BOOL WINAPI MZ_Current( void )
 672 {
 673   return (dosvm_pid != 0); /* FIXME: do a better check */
 674 }
 675
 676 #else /* !MZ_SUPPORTED */
 677
 678 /***********************************************************************
 679  *              wine_load_dos_exe (WINEDOS.@)
 680  */
 681 void WINAPI wine_load_dos_exe( LPCSTR filename, LPCSTR cmdline )
 682 {
 683   WARN("DOS executables not supported on this platform\n");
 684   SetLastError(ERROR_BAD_FORMAT);
 685 }
 686
 687 /***********************************************************************
 688  *              MZ_Exec
 689  */
 690 BOOL WINAPI MZ_Exec( CONTEXT86 *context, LPCSTR filename, BYTE func, LPVOID paramblk )
 691 {
 692   /* can't happen */
 693   SetLastError(ERROR_BAD_FORMAT);
 694   return FALSE;
 695 }
 696
 697 /***********************************************************************
 698  *              MZ_AllocDPMITask
 699  */
 700 void WINAPI MZ_AllocDPMITask( void )
 701 {
 702     ERR("Actual real-mode calls not supported on this platform!\n");
 703 }
 704
 705 /***********************************************************************
 706  *              MZ_RunInThread
 707  */
 708 void WINAPI MZ_RunInThread( PAPCFUNC proc, ULONG_PTR arg )
 709 {
 710     proc(arg);
 711 }
 712
 713 /***********************************************************************
 714  *              MZ_Exit
 715  */
 716 void WINAPI MZ_Exit( CONTEXT86 *context, BOOL cs_psp, WORD retval )
 717 {
 718   ExitThread( retval );
 719 }
 720
 721 /***********************************************************************
 722  *              MZ_Current
 723  */
 724 BOOL WINAPI MZ_Current( void )
 725 {
 726     return FALSE;
 727 }
 728
 729 #endif /* !MZ_SUPPORTED */