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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, 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 #ifdef HAVE_SYS_STAT_H
  37 # include <sys/stat.h>
  38 #endif
  39 #ifdef HAVE_SYS_TIME_H
  40 # include <sys/time.h>
  41 #endif
  42 #include "windef.h"
  43 #include "winbase.h"
  44 #include "wine/winbase16.h"
  45 #include "wingdi.h"
  46 #include "winuser.h"
  47 #include "winerror.h"
  48 #include "wine/debug.h"
  49 #include "dosexe.h"
  50 #include "dosvm.h"
  51 #include "vga.h"
  52
  53 WINE_DEFAULT_DEBUG_CHANNEL(module);
  54
  55 static BOOL DOSVM_isdosexe;
  56
  57 /**********************************************************************
  58  *          DOSVM_IsWin16
  59  *
  60  * Return TRUE if we are in Windows process.
  61  */
  62 BOOL DOSVM_IsWin16(void)
  63 {
  64   return DOSVM_isdosexe ? FALSE : TRUE;
  65 }
  66
  67 #ifdef MZ_SUPPORTED
  68
  69 #ifdef HAVE_SYS_MMAN_H
  70 # include <sys/mman.h>
  71 #endif
  72
  73 /* define this to try mapping through /proc/pid/mem instead of a temp file,
  74    but Linus doesn't like mmapping /proc/pid/mem, so it doesn't work for me */
  75 #undef MZ_MAPSELF
  76
  77 #define BIOS_DATA_SEGMENT 0x40
  78 #define PSP_SIZE 0x10
  79
  80 #define SEG16(ptr,seg) ((LPVOID)((BYTE*)ptr+((DWORD)(seg)<<4)))
  81 #define SEGPTR16(ptr,segptr) ((LPVOID)((BYTE*)ptr+((DWORD)SELECTOROF(segptr)<<4)+OFFSETOF(segptr)))
  82
  83 /* structures for EXEC */
  84
  85 #include "pshpack1.h"
  86
  87 typedef struct {
  88   WORD env_seg;
  89   DWORD cmdline;
  90   DWORD fcb1;
  91   DWORD fcb2;
  92   WORD init_sp;
  93   WORD init_ss;
  94   WORD init_ip;
  95   WORD init_cs;
  96 } ExecBlock;
  97
  98 typedef struct {
  99   WORD load_seg;
 100   WORD rel_seg;
 101 } OverlayBlock;
 102
 103 #include "poppack.h"
 104
 105 /* global variables */
 106
 107 pid_t dosvm_pid;
 108
 109 static WORD init_cs,init_ip,init_ss,init_sp;
 110 static HANDLE dosvm_thread, loop_thread;
 111 static DWORD dosvm_tid, loop_tid;
 112
 113 static void MZ_Launch( LPCSTR cmdtail, int length );
 114 static BOOL MZ_InitTask(void);
 115
 116 static void MZ_CreatePSP( LPVOID lpPSP, WORD env, WORD par )
 117 {
 118   PDB16*psp=lpPSP;
 119
 120   psp->int20=0x20CD; /* int 20 */
 121   /* some programs use this to calculate how much memory they need */
 122   psp->nextParagraph=0x9FFF; /* FIXME: use a real value */
 123   /* FIXME: dispatcher */
 124   psp->savedint22 = DOSVM_GetRMHandler(0x22);
 125   psp->savedint23 = DOSVM_GetRMHandler(0x23);
 126   psp->savedint24 = DOSVM_GetRMHandler(0x24);
 127   psp->parentPSP=par;
 128   psp->environment=env;
 129   /* FIXME: more PSP stuff */
 130 }
 131
 132 static void MZ_FillPSP( LPVOID lpPSP, LPCSTR cmdtail, int length )
 133 {
 134     PDB16 *psp = lpPSP;
 135
 136     if(length > 127)
 137     {
 138         WARN( "Command tail truncated! (length %d)\n", length );
 139         length = 126;
 140     }
 141
 142     psp->cmdLine[0] = length;
 143
 144     /*
 145      * Length of exactly 127 bytes means that full command line is
 146      * stored in environment variable CMDLINE and PSP contains
 147      * command tail truncated to 126 bytes.
 148      */
 149     if(length == 127)
 150         length = 126;
 151
 152     if(length > 0)
 153         memmove(psp->cmdLine+1, cmdtail, length);
 154
 155     psp->cmdLine[length+1] = '\r';
 156
 157     /* FIXME: more PSP stuff */
 158 }
 159
 160 static WORD MZ_InitEnvironment( LPCSTR env, LPCSTR name )
 161 {
 162  unsigned sz=0;
 163  unsigned i=0;
 164  WORD seg;
 165  LPSTR envblk;
 166
 167  if (env) {
 168   /* get size of environment block */
 169   while (env[sz++]) sz+=strlen(env+sz)+1;
 170  } else sz++;
 171  /* allocate it */
 172  envblk=DOSMEM_AllocBlock(sz+sizeof(WORD)+strlen(name)+1,&seg);
 173  /* fill it */
 174  if (env) {
 175   memcpy(envblk,env,sz);
 176  } else envblk[0]=0;
 177  /* DOS environment variables are uppercase */
 178  while (envblk[i]){
 179   while (envblk[i] != '='){
 180    if (envblk[i]>='a' && envblk[i] <= 'z'){
 181     envblk[i] -= 32;
 182    }
 183    i++;
 184   }
 185   i += strlen(envblk+i) + 1;
 186  }
 187  /* DOS 3.x: the block contains 1 additional string */
 188  *(WORD*)(envblk+sz)=1;
 189  /* being the program name itself */
 190  strcpy(envblk+sz+sizeof(WORD),name);
 191  return seg;
 192 }
 193
 194 static BOOL MZ_InitMemory(void)
 195 {
 196     /* initialize the memory */
 197     TRACE("Initializing DOS memory structures\n");
 198     DOSMEM_MapDosLayout();
 199     DOSDEV_InstallDOSDevices();
 200     MSCDEX_InstallCDROM();
 201
 202     return TRUE;
 203 }
 204
 205 static BOOL MZ_DoLoadImage( HANDLE hFile, LPCSTR filename, OverlayBlock *oblk, WORD par_env_seg )
 206 {
 207   IMAGE_DOS_HEADER mz_header;
 208   DWORD image_start,image_size,min_size,max_size,avail;
 209   BYTE*psp_start,*load_start;
 210   LPSTR oldenv = 0;
 211   int x, old_com=0, alloc;
 212   SEGPTR reloc;
 213   WORD env_seg, load_seg, rel_seg, oldpsp_seg;
 214   DWORD len;
 215
 216   if (DOSVM_psp) {
 217     /* DOS process already running, inherit from it */
 218     PDB16* par_psp;
 219     alloc=0;
 220     oldpsp_seg = DOSVM_psp;
 221     if( !par_env_seg) {
 222         par_psp = (PDB16*)((DWORD)DOSVM_psp << 4);
 223         oldenv = (LPSTR)((DWORD)par_psp->environment << 4);
 224     }
 225   } else {
 226     /* allocate new DOS process, inheriting from Wine environment */
 227     alloc=1;
 228     oldpsp_seg = 0;
 229     if( !par_env_seg)
 230         oldenv = GetEnvironmentStringsA();
 231   }
 232
 233  SetFilePointer(hFile,0,NULL,FILE_BEGIN);
 234  if (   !ReadFile(hFile,&mz_header,sizeof(mz_header),&len,NULL)
 235      || len != sizeof(mz_header)
 236      || mz_header.e_magic != IMAGE_DOS_SIGNATURE) {
 237   char *p = strrchr( filename, '.' );
 238   if (!p || strcasecmp( p, ".com" ))  /* check for .COM extension */
 239   {
 240       SetLastError(ERROR_BAD_FORMAT);
 241       goto load_error;
 242   }
 243   old_com=1; /* assume .COM file */
 244   image_start=0;
 245   image_size=GetFileSize(hFile,NULL);
 246   min_size=0x10000; max_size=0x100000;
 247   mz_header.e_crlc=0;
 248   mz_header.e_ss=0; mz_header.e_sp=0xFFFE;
 249   mz_header.e_cs=0; mz_header.e_ip=0x100;
 250  } else {
 251   /* calculate load size */
 252   image_start=mz_header.e_cparhdr<<4;
 253   image_size=mz_header.e_cp<<9; /* pages are 512 bytes */
 254   /* From Ralf Brown Interrupt List: If the word at offset 02h is 4, it should
 255    * be treated as 00h, since pre-1.10 versions of the MS linker set it that
 256    * way. */
 257   if ((mz_header.e_cblp!=0)&&(mz_header.e_cblp!=4)) image_size-=512-mz_header.e_cblp;
 258   image_size-=image_start;
 259   min_size=image_size+((DWORD)mz_header.e_minalloc<<4)+(PSP_SIZE<<4);
 260   max_size=image_size+((DWORD)mz_header.e_maxalloc<<4)+(PSP_SIZE<<4);
 261  }
 262
 263   if (alloc) MZ_InitMemory();
 264
 265   if (oblk) {
 266     /* load overlay into preallocated memory */
 267     load_seg=oblk->load_seg;
 268     rel_seg=oblk->rel_seg;
 269     load_start=(LPBYTE)((DWORD)load_seg<<4);
 270   } else {
 271     /* allocate environment block */
 272     if( par_env_seg)
 273         env_seg = par_env_seg;
 274     else
 275         env_seg=MZ_InitEnvironment(oldenv, filename);
 276     if (alloc)
 277         FreeEnvironmentStringsA( oldenv);
 278
 279     /* allocate memory for the executable */
 280     TRACE("Allocating DOS memory (min=%d, max=%d)\n",min_size,max_size);
 281     avail=DOSMEM_Available();
 282     if (avail<min_size) {
 283       ERR("insufficient DOS memory\n");
 284       SetLastError(ERROR_NOT_ENOUGH_MEMORY);
 285       goto load_error;
 286     }
 287     if (avail>max_size) avail=max_size;
 288     psp_start=DOSMEM_AllocBlock(avail,&DOSVM_psp);
 289     if (!psp_start) {
 290       ERR("error allocating DOS memory\n");
 291       SetLastError(ERROR_NOT_ENOUGH_MEMORY);
 292       goto load_error;
 293     }
 294     load_seg=DOSVM_psp+(old_com?0:PSP_SIZE);
 295     rel_seg=load_seg;
 296     load_start=psp_start+(PSP_SIZE<<4);
 297     MZ_CreatePSP(psp_start, env_seg, oldpsp_seg);
 298   }
 299
 300  /* load executable image */
 301  TRACE("loading DOS %s image, %08x bytes\n",old_com?"COM":"EXE",image_size);
 302  SetFilePointer(hFile,image_start,NULL,FILE_BEGIN);
 303  if (!ReadFile(hFile,load_start,image_size,&len,NULL) || len != image_size) {
 304   /* check if this is due to the workaround for the pre-1.10 MS linker and we
 305      realy had only 4 bytes on the last page */
 306   if (mz_header.e_cblp != 4 || image_size - len != 512 - 4) {
 307     SetLastError(ERROR_BAD_FORMAT);
 308     goto load_error;
 309   }
 310  }
 311
 312  if (mz_header.e_crlc) {
 313   /* load relocation table */
 314   TRACE("loading DOS EXE relocation table, %d entries\n",mz_header.e_crlc);
 315   /* FIXME: is this too slow without read buffering? */
 316   SetFilePointer(hFile,mz_header.e_lfarlc,NULL,FILE_BEGIN);
 317   for (x=0; x<mz_header.e_crlc; x++) {
 318    if (!ReadFile(hFile,&reloc,sizeof(reloc),&len,NULL) || len != sizeof(reloc)) {
 319     SetLastError(ERROR_BAD_FORMAT);
 320     goto load_error;
 321    }
 322    *(WORD*)SEGPTR16(load_start,reloc)+=rel_seg;
 323   }
 324  }
 325
 326   if (!oblk) {
 327     init_cs = load_seg+mz_header.e_cs;
 328     init_ip = mz_header.e_ip;
 329     init_ss = load_seg+mz_header.e_ss;
 330     init_sp = mz_header.e_sp;
 331     if (old_com){
 332       /* .COM files exit with ret. Make sure they jump to psp start (=int 20) */
 333       WORD* stack = PTR_REAL_TO_LIN(init_ss, init_sp);
 334       *stack = 0;
 335     }
 336
 337     TRACE("entry point: %04x:%04x\n",init_cs,init_ip);
 338   }
 339
 340   if (alloc && !MZ_InitTask()) {
 341     SetLastError(ERROR_GEN_FAILURE);
 342     return FALSE;
 343   }
 344
 345   return TRUE;
 346
 347 load_error:
 348   DOSVM_psp = oldpsp_seg;
 349
 350   return FALSE;
 351 }
 352
 353 /***********************************************************************
 354  *              wine_load_dos_exe (WINEDOS.@)
 355  *
 356  * Called from WineVDM when a new real-mode DOS process is started.
 357  * Loads DOS program into memory and executes the program.
 358  */
 359 void WINAPI wine_load_dos_exe( LPCSTR filename, LPCSTR cmdline )
 360 {
 361     char dos_cmdtail[126];
 362     int  dos_length = 0;
 363
 364     HANDLE hFile = CreateFileA( filename, GENERIC_READ, FILE_SHARE_READ,
 365                                 NULL, OPEN_EXISTING, 0, 0 );
 366     if (hFile == INVALID_HANDLE_VALUE) return;
 367     DOSVM_isdosexe = TRUE;
 368
 369     if(cmdline && *cmdline)
 370     {
 371         dos_length = strlen(cmdline);
 372         memmove( dos_cmdtail + 1, cmdline,
 373                  (dos_length < 125) ? dos_length : 125 );
 374
 375         /* Non-empty command tail always starts with at least one space. */
 376         dos_cmdtail[0] = ' ';
 377         dos_length++;
 378
 379         /*
 380          * If command tail is longer than 126 characters,
 381          * set tail length to 127 and fill CMDLINE environment variable
 382          * with full command line (this includes filename).
 383          */
 384         if (dos_length > 126)
 385         {
 386             char *cmd = HeapAlloc( GetProcessHeap(), 0,
 387                                    dos_length + strlen(filename) + 4 );
 388             char *ptr = cmd;
 389
 390             if (!cmd)
 391                 return;
 392
 393             /*
 394              * Append filename. If path includes spaces, quote the path.
 395              */
 396             if (strchr(filename, ' '))
 397             {
 398                 *ptr++ = '\"';
 399                 strcpy( ptr, filename );
 400                 ptr += strlen(filename);
 401                 *ptr++ = '\"';
 402             }
 403             else
 404             {
 405                 strcpy( ptr, filename );
 406                 ptr += strlen(filename);
 407             }
 408
 409             /*
 410              * Append command tail.
 411              */
 412             if (cmdline[0] != ' ')
 413                 *ptr++ = ' ';
 414             strcpy( ptr, cmdline );
 415
 416             /*
 417              * Set environment variable. This will be passed to
 418              * new DOS process.
 419              */
 420             if (!SetEnvironmentVariableA( "CMDLINE", cmd ))
 421             {
 422                 HeapFree(GetProcessHeap(), 0, cmd );
 423                 return;
 424             }
 425
 426             HeapFree(GetProcessHeap(), 0, cmd );
 427             dos_length = 127;
 428         }
 429     }
 430
 431     if (MZ_DoLoadImage( hFile, filename, NULL, 0 ))
 432         MZ_Launch( dos_cmdtail, dos_length );
 433 }
 434
 435 /***********************************************************************
 436  *              MZ_Exec
 437  *
 438  * this may only be called from existing DOS processes
 439  */
 440 BOOL WINAPI MZ_Exec( CONTEXT86 *context, LPCSTR filename, BYTE func, LPVOID paramblk )
 441 {
 442   DWORD binType;
 443   STARTUPINFOA st;
 444   PROCESS_INFORMATION pe;
 445   HANDLE hFile;
 446
 447   BOOL ret = FALSE;
 448
 449   if(!GetBinaryTypeA(filename, &binType))   /* determine what kind of binary this is */
 450   {
 451     return FALSE; /* binary is not an executable */
 452   }
 453
 454   /* handle non-dos executables */
 455   if(binType != SCS_DOS_BINARY)
 456   {
 457     if(func == 0) /* load and execute */
 458     {
 459       LPSTR fullCmdLine;
 460       WORD fullCmdLength;
 461       LPBYTE psp_start = (LPBYTE)((DWORD)DOSVM_psp << 4);
 462       PDB16 *psp = (PDB16 *)psp_start;
 463       ExecBlock *blk = (ExecBlock *)paramblk;
 464       LPBYTE cmdline = PTR_REAL_TO_LIN(SELECTOROF(blk->cmdline),OFFSETOF(blk->cmdline));
 465       LPBYTE envblock = PTR_REAL_TO_LIN(psp->environment, 0);
 466       int    cmdLength = cmdline[0];
 467
 468       /*
 469        * If cmdLength is 127, command tail is truncated and environment
 470        * variable CMDLINE should contain full command line
 471        * (this includes filename).
 472        */
 473       if (cmdLength == 127)
 474       {
 475           FIXME( "CMDLINE argument passing is unimplemented.\n" );
 476           cmdLength = 126; /* FIXME */
 477       }
 478
 479       fullCmdLength = (strlen(filename) + 1) + cmdLength + 1; /* filename + space + cmdline + terminating null character */
 480
 481       fullCmdLine = HeapAlloc(GetProcessHeap(), 0, fullCmdLength);
 482       if(!fullCmdLine) return FALSE; /* return false on memory alloc failure */
 483
 484       /* build the full command line from the executable file and the command line being passed in */
 485       snprintf(fullCmdLine, fullCmdLength, "%s ", filename); /* start off with the executable filename and a space */
 486       memcpy(fullCmdLine + strlen(fullCmdLine), cmdline + 1, cmdLength); /* append cmdline onto the end */
 487       fullCmdLine[fullCmdLength - 1] = 0; /* null terminate string */
 488
 489       ZeroMemory (&st, sizeof(STARTUPINFOA));
 490       st.cb = sizeof(STARTUPINFOA);
 491       ret = CreateProcessA (NULL, fullCmdLine, NULL, NULL, TRUE, 0, envblock, NULL, &st, &pe);
 492
 493       /* wait for the app to finish and clean up PROCESS_INFORMATION handles */
 494       if(ret)
 495       {
 496         WaitForSingleObject(pe.hProcess, INFINITE);  /* wait here until the child process is complete */
 497         CloseHandle(pe.hProcess);
 498         CloseHandle(pe.hThread);
 499       }
 500
 501       HeapFree(GetProcessHeap(), 0, fullCmdLine);  /* free the memory we allocated */
 502     }
 503     else
 504     {
 505       FIXME("EXEC type of %d not implemented for non-dos executables\n", func);
 506       ret = FALSE;
 507     }
 508
 509     return ret;
 510   } /* if(binType != SCS_DOS_BINARY) */
 511
 512
 513   /* handle dos executables */
 514
 515   hFile = CreateFileA( filename, GENERIC_READ, FILE_SHARE_READ,
 516                              NULL, OPEN_EXISTING, 0, 0);
 517   if (hFile == INVALID_HANDLE_VALUE) return FALSE;
 518
 519   switch (func) {
 520   case 0: /* load and execute */
 521   case 1: /* load but don't execute */
 522     {
 523       /* save current process's return SS:SP now */
 524       LPBYTE psp_start = (LPBYTE)((DWORD)DOSVM_psp << 4);
 525       PDB16 *psp = (PDB16 *)psp_start;
 526       psp->saveStack = (DWORD)MAKESEGPTR(context->SegSs, LOWORD(context->Esp));
 527     }
 528     ret = MZ_DoLoadImage( hFile, filename, NULL, ((ExecBlock *)paramblk)->env_seg );
 529     if (ret) {
 530       /* MZ_LoadImage created a new PSP and loaded new values into it,
 531        * let's work on the new values now */
 532       LPBYTE psp_start = (LPBYTE)((DWORD)DOSVM_psp << 4);
 533       ExecBlock *blk = (ExecBlock *)paramblk;
 534       LPBYTE cmdline = PTR_REAL_TO_LIN(SELECTOROF(blk->cmdline),OFFSETOF(blk->cmdline));
 535
 536       /* First character contains the length of the command line. */
 537       MZ_FillPSP(psp_start, (LPSTR)cmdline + 1, cmdline[0]);
 538
 539       /* the lame MS-DOS engineers decided that the return address should be in int22 */
 540       DOSVM_SetRMHandler(0x22, (FARPROC16)MAKESEGPTR(context->SegCs, LOWORD(context->Eip)));
 541       if (func) {
 542         /* don't execute, just return startup state */
 543         /*
 544          * From Ralph Brown:
 545          *  For function 01h, the AX value to be passed to the child program
 546          *  is put on top of the child's stack
 547          */
 548         LPBYTE stack;
 549         init_sp -= 2;
 550         stack = (LPBYTE) CTX_SEG_OFF_TO_LIN(context, init_ss, init_sp);
 551         /* FIXME: push AX correctly */
 552         stack[0] = 0x00;    /* push AL */
 553         stack[1] = 0x00;    /* push AH */
 554
 555         blk->init_cs = init_cs;
 556         blk->init_ip = init_ip;
 557         blk->init_ss = init_ss;
 558         blk->init_sp = init_sp;
 559       } else {
 560         /* execute by making us return to new process */
 561         context->SegCs = init_cs;
 562         context->Eip   = init_ip;
 563         context->SegSs = init_ss;
 564         context->Esp   = init_sp;
 565         context->SegDs = DOSVM_psp;
 566         context->SegEs = DOSVM_psp;
 567         context->Eax   = 0;
 568       }
 569     }
 570     break;
 571   case 3: /* load overlay */
 572     {
 573       OverlayBlock *blk = (OverlayBlock *)paramblk;
 574       ret = MZ_DoLoadImage( hFile, filename, blk, 0);
 575     }
 576     break;
 577   default:
 578     FIXME("EXEC load type %d not implemented\n", func);
 579     SetLastError(ERROR_INVALID_FUNCTION);
 580     break;
 581   }
 582   CloseHandle(hFile);
 583   return ret;
 584 }
 585
 586 /***********************************************************************
 587  *              MZ_AllocDPMITask
 588  */
 589 void WINAPI MZ_AllocDPMITask( void )
 590 {
 591   MZ_InitMemory();
 592   MZ_InitTask();
 593 }
 594
 595 /***********************************************************************
 596  *              MZ_RunInThread
 597  */
 598 void WINAPI MZ_RunInThread( PAPCFUNC proc, ULONG_PTR arg )
 599 {
 600   if (loop_thread) {
 601     DOS_SPC spc;
 602     HANDLE event;
 603
 604     spc.proc = proc;
 605     spc.arg = arg;
 606     event = CreateEventW(NULL, TRUE, FALSE, NULL);
 607     PostThreadMessageA(loop_tid, WM_USER, (WPARAM)event, (LPARAM)&spc);
 608     WaitForSingleObject(event, INFINITE);
 609     CloseHandle(event);
 610   } else
 611     proc(arg);
 612 }
 613
 614 static DWORD WINAPI MZ_DOSVM( LPVOID lpExtra )
 615 {
 616   CONTEXT context;
 617   DWORD ret;
 618
 619   dosvm_pid = getpid();
 620
 621   memset( &context, 0, sizeof(context) );
 622   context.SegCs  = init_cs;
 623   context.Eip    = init_ip;
 624   context.SegSs  = init_ss;
 625   context.Esp    = init_sp;
 626   context.SegDs  = DOSVM_psp;
 627   context.SegEs  = DOSVM_psp;
 628   context.EFlags = V86_FLAG | VIF_MASK;
 629   DOSVM_SetTimer(0x10000);
 630   ret = DOSVM_Enter( &context );
 631
 632   dosvm_pid = 0;
 633   return ret;
 634 }
 635
 636 static BOOL MZ_InitTask(void)
 637 {
 638   if (!DuplicateHandle(GetCurrentProcess(), GetCurrentThread(),
 639                        GetCurrentProcess(), &loop_thread,
 640                        0, FALSE, DUPLICATE_SAME_ACCESS))
 641     return FALSE;
 642   dosvm_thread = CreateThread(NULL, 0, MZ_DOSVM, NULL, CREATE_SUSPENDED, &dosvm_tid);
 643   if (!dosvm_thread) {
 644     CloseHandle(loop_thread);
 645     loop_thread = 0;
 646     return FALSE;
 647   }
 648   loop_tid = GetCurrentThreadId();
 649   return TRUE;
 650 }
 651
 652 static void MZ_Launch( LPCSTR cmdtail, int length )
 653 {
 654   TDB *pTask = GlobalLock16( GetCurrentTask() );
 655   BYTE *psp_start = PTR_REAL_TO_LIN( DOSVM_psp, 0 );
 656   DWORD rv;
 657   SYSLEVEL *lock;
 658
 659   MZ_FillPSP(psp_start, cmdtail, length);
 660   pTask->flags |= TDBF_WINOLDAP;
 661
 662   /* DTA is set to PSP:0080h when a program is started. */
 663   pTask->dta = MAKESEGPTR( DOSVM_psp, 0x80 );
 664
 665   GetpWin16Lock( &lock );
 666   _LeaveSysLevel( lock );
 667
 668   ResumeThread(dosvm_thread);
 669   rv = DOSVM_Loop(dosvm_thread);
 670
 671   CloseHandle(dosvm_thread);
 672   dosvm_thread = 0; dosvm_tid = 0;
 673   CloseHandle(loop_thread);
 674   loop_thread = 0; loop_tid = 0;
 675
 676   VGA_Clean();
 677   ExitProcess(rv);
 678 }
 679
 680 /***********************************************************************
 681  *              MZ_Exit
 682  */
 683 void WINAPI MZ_Exit( CONTEXT86 *context, BOOL cs_psp, WORD retval )
 684 {
 685   if (DOSVM_psp) {
 686     WORD psp_seg = cs_psp ? context->SegCs : DOSVM_psp;
 687     LPBYTE psp_start = (LPBYTE)((DWORD)psp_seg << 4);
 688     PDB16 *psp = (PDB16 *)psp_start;
 689     WORD parpsp = psp->parentPSP; /* check for parent DOS process */
 690     if (parpsp) {
 691       /* retrieve parent's return address */
 692       FARPROC16 retaddr = DOSVM_GetRMHandler(0x22);
 693       /* restore interrupts */
 694       DOSVM_SetRMHandler(0x22, psp->savedint22);
 695       DOSVM_SetRMHandler(0x23, psp->savedint23);
 696       DOSVM_SetRMHandler(0x24, psp->savedint24);
 697       /* FIXME: deallocate file handles etc */
 698       /* free process's associated memory
 699        * FIXME: walk memory and deallocate all blocks owned by process */
 700       DOSMEM_FreeBlock( PTR_REAL_TO_LIN(psp->environment,0) );
 701       DOSMEM_FreeBlock( PTR_REAL_TO_LIN(DOSVM_psp,0) );
 702       /* switch to parent's PSP */
 703       DOSVM_psp = parpsp;
 704       psp_start = (LPBYTE)((DWORD)parpsp << 4);
 705       psp = (PDB16 *)psp_start;
 706       /* now return to parent */
 707       DOSVM_retval = retval;
 708       context->SegCs = SELECTOROF(retaddr);
 709       context->Eip   = OFFSETOF(retaddr);
 710       context->SegSs = SELECTOROF(psp->saveStack);
 711       context->Esp   = OFFSETOF(psp->saveStack);
 712       return;
 713     } else
 714       TRACE("killing DOS task\n");
 715   }
 716   ExitThread( retval );
 717 }
 718
 719
 720 /***********************************************************************
 721  *              MZ_Current
 722  */
 723 BOOL WINAPI MZ_Current( void )
 724 {
 725   return (dosvm_pid != 0); /* FIXME: do a better check */
 726 }
 727
 728 #else /* !MZ_SUPPORTED */
 729
 730 /***********************************************************************
 731  *              wine_load_dos_exe (WINEDOS.@)
 732  */
 733 void WINAPI wine_load_dos_exe( LPCSTR filename, LPCSTR cmdline )
 734 {
 735     FIXME("DOS executables not supported on this platform\n");
 736     SetLastError(ERROR_BAD_FORMAT);
 737 }
 738
 739 /***********************************************************************
 740  *              MZ_Exec
 741  */
 742 BOOL WINAPI MZ_Exec( CONTEXT86 *context, LPCSTR filename, BYTE func, LPVOID paramblk )
 743 {
 744   /* can't happen */
 745   SetLastError(ERROR_BAD_FORMAT);
 746   return FALSE;
 747 }
 748
 749 /***********************************************************************
 750  *              MZ_AllocDPMITask
 751  */
 752 void WINAPI MZ_AllocDPMITask( void )
 753 {
 754     FIXME("Actual real-mode calls not supported on this platform!\n");
 755 }
 756
 757 /***********************************************************************
 758  *              MZ_RunInThread
 759  */
 760 void WINAPI MZ_RunInThread( PAPCFUNC proc, ULONG_PTR arg )
 761 {
 762     proc(arg);
 763 }
 764
 765 /***********************************************************************
 766  *              MZ_Exit
 767  */
 768 void WINAPI MZ_Exit( CONTEXT86 *context, BOOL cs_psp, WORD retval )
 769 {
 770   ExitThread( retval );
 771 }
 772
 773 /***********************************************************************
 774  *              MZ_Current
 775  */
 776 BOOL WINAPI MZ_Current( void )
 777 {
 778     return FALSE;
 779 }
 780
 781 #endif /* !MZ_SUPPORTED */