dlls/krnl386.exe16/task.c

   1 /*
   2  * Task functions
   3  *
   4  * Copyright 1995 Alexandre Julliard
   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
  21 #include <stdarg.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <assert.h>
  25
  26 #include "windef.h"
  27 #include "winbase.h"
  28 #include "wingdi.h"
  29 #include "winnt.h"
  30 #include "wownt32.h"
  31 #include "winuser.h"
  32
  33 #include "wine/winbase16.h"
  34 #include "winternl.h"
  35 #include "kernel16_private.h"
  36
  37 #include "wine/debug.h"
  38
  39 WINE_DEFAULT_DEBUG_CHANNEL(task);
  40
  41 #include "pshpack1.h"
  42
  43 struct thunk
  44 {
  45     BYTE      movw;
  46     HANDLE16  instance;
  47     BYTE      ljmp;
  48     FARPROC16 func;
  49 };
  50
  51 /* Segment containing MakeProcInstance() thunks */
  52 typedef struct
  53 {
  54     WORD  next;       /* Selector of next segment */
  55     WORD  magic;      /* Thunks signature */
  56     WORD  unused;
  57     WORD  free;       /* Head of the free list */
  58     struct thunk thunks[1];
  59 } THUNKS;
  60
  61 #include "poppack.h"
  62
  63 #define THUNK_MAGIC  ('P' | ('T' << 8))
  64
  65   /* Min. number of thunks allocated when creating a new segment */
  66 #define MIN_THUNKS  32
  67
  68 #define TDB_MAGIC    ('T' | ('D' << 8))
  69
  70 static THHOOK DefaultThhook;
  71 THHOOK *pThhook = &DefaultThhook;
  72
  73 #define hFirstTask   (pThhook->HeadTDB)
  74 #define hLockedTask  (pThhook->LockTDB)
  75
  76 static UINT16 nTaskCount = 0;
  77
  78 static HTASK16 initial_task, main_task;
  79
  80 /***********************************************************************
  81  *           TASK_InstallTHHook
  82  */
  83 void TASK_InstallTHHook( THHOOK *pNewThhook )
  84 {
  85      THHOOK *pOldThhook = pThhook;
  86
  87      pThhook = pNewThhook? pNewThhook : &DefaultThhook;
  88
  89      *pThhook = *pOldThhook;
  90 }
  91
  92 /***********************************************************************
  93  *           TASK_GetPtr
  94  */
  95 static TDB *TASK_GetPtr( HTASK16 hTask )
  96 {
  97     return GlobalLock16( hTask );
  98 }
  99
 100
 101 /***********************************************************************
 102  *           TASK_GetCurrent
 103  */
 104 TDB *TASK_GetCurrent(void)
 105 {
 106     return TASK_GetPtr( GetCurrentTask() );
 107 }
 108
 109
 110 /***********************************************************************
 111  *           TASK_LinkTask
 112  */
 113 static void TASK_LinkTask( HTASK16 hTask )
 114 {
 115     HTASK16 *prevTask;
 116     TDB *pTask;
 117
 118     if (!(pTask = TASK_GetPtr( hTask ))) return;
 119     prevTask = &hFirstTask;
 120     while (*prevTask)
 121     {
 122         TDB *prevTaskPtr = TASK_GetPtr( *prevTask );
 123         if (prevTaskPtr->priority >= pTask->priority) break;
 124         prevTask = &prevTaskPtr->hNext;
 125     }
 126     pTask->hNext = *prevTask;
 127     *prevTask = hTask;
 128     nTaskCount++;
 129 }
 130
 131
 132 /***********************************************************************
 133  *           TASK_UnlinkTask
 134  */
 135 static void TASK_UnlinkTask( HTASK16 hTask )
 136 {
 137     HTASK16 *prevTask;
 138     TDB *pTask;
 139
 140     prevTask = &hFirstTask;
 141     while (*prevTask && (*prevTask != hTask))
 142     {
 143         pTask = TASK_GetPtr( *prevTask );
 144         prevTask = &pTask->hNext;
 145     }
 146     if (*prevTask)
 147     {
 148         pTask = TASK_GetPtr( *prevTask );
 149         *prevTask = pTask->hNext;
 150         pTask->hNext = 0;
 151         nTaskCount--;
 152     }
 153 }
 154
 155
 156 /***********************************************************************
 157  *           TASK_CreateThunks
 158  *
 159  * Create a thunk free-list in segment 'handle', starting from offset 'offset'
 160  * and containing 'count' entries.
 161  */
 162 static void TASK_CreateThunks( HGLOBAL16 handle, WORD offset, WORD count )
 163 {
 164     int i;
 165     THUNKS *pThunk;
 166
 167     pThunk = (THUNKS *)((BYTE *)GlobalLock16( handle ) + offset);
 168     pThunk->next = 0;
 169     pThunk->magic = THUNK_MAGIC;
 170     pThunk->free = FIELD_OFFSET( THUNKS, thunks );
 171     for (i = 0; i < count-1; i++)
 172         *(WORD *)&pThunk->thunks[i] = FIELD_OFFSET( THUNKS, thunks[i+1] );
 173     *(WORD *)&pThunk->thunks[i] = 0;  /* Last thunk */
 174 }
 175
 176
 177 /***********************************************************************
 178  *           TASK_AllocThunk
 179  *
 180  * Allocate a thunk for MakeProcInstance().
 181  */
 182 static SEGPTR TASK_AllocThunk(void)
 183 {
 184     TDB *pTask;
 185     THUNKS *pThunk;
 186     WORD sel, base;
 187
 188     if (!(pTask = TASK_GetCurrent())) return 0;
 189     sel = pTask->hCSAlias;
 190     pThunk = (THUNKS *)pTask->thunks;
 191     base = (char *)pThunk - (char *)pTask;
 192     while (!pThunk->free)
 193     {
 194         sel = pThunk->next;
 195         if (!sel)  /* Allocate a new segment */
 196         {
 197             sel = GLOBAL_Alloc( GMEM_FIXED, FIELD_OFFSET( THUNKS, thunks[MIN_THUNKS] ),
 198                                 pTask->hPDB, LDT_FLAGS_CODE );
 199             if (!sel) return 0;
 200             TASK_CreateThunks( sel, 0, MIN_THUNKS );
 201             pThunk->next = sel;
 202         }
 203         pThunk = GlobalLock16( sel );
 204         base = 0;
 205     }
 206     base += pThunk->free;
 207     pThunk->free = *(WORD *)((BYTE *)pThunk + pThunk->free);
 208     return MAKESEGPTR( sel, base );
 209 }
 210
 211
 212 /***********************************************************************
 213  *           TASK_FreeThunk
 214  *
 215  * Free a MakeProcInstance() thunk.
 216  */
 217 static BOOL TASK_FreeThunk( SEGPTR thunk )
 218 {
 219     TDB *pTask;
 220     THUNKS *pThunk;
 221     WORD sel, base;
 222
 223     if (!(pTask = TASK_GetCurrent())) return FALSE;
 224     sel = pTask->hCSAlias;
 225     pThunk = (THUNKS *)pTask->thunks;
 226     base = (char *)pThunk - (char *)pTask;
 227     while (sel && (sel != HIWORD(thunk)))
 228     {
 229         sel = pThunk->next;
 230         pThunk = GlobalLock16( sel );
 231         base = 0;
 232     }
 233     if (!sel) return FALSE;
 234     *(WORD *)((BYTE *)pThunk + LOWORD(thunk) - base) = pThunk->free;
 235     pThunk->free = LOWORD(thunk) - base;
 236     return TRUE;
 237 }
 238
 239
 240 /***********************************************************************
 241  *           TASK_Create
 242  *
 243  * NOTE: This routine might be called by a Win32 thread. Thus, we need
 244  *       to be careful to protect global data structures. We do this
 245  *       by entering the Win16Lock while linking the task into the
 246  *       global task list.
 247  */
 248 static TDB *TASK_Create( NE_MODULE *pModule, UINT16 cmdShow, LPCSTR cmdline, BYTE len )
 249 {
 250     HTASK16 hTask;
 251     TDB *pTask;
 252     FARPROC16 proc;
 253     char curdir[MAX_PATH];
 254     HMODULE16 hModule = pModule ? pModule->self : 0;
 255
 256       /* Allocate the task structure */
 257
 258     hTask = GlobalAlloc16( GMEM_FIXED | GMEM_ZEROINIT, sizeof(TDB) );
 259     if (!hTask) return NULL;
 260     pTask = TASK_GetPtr( hTask );
 261     FarSetOwner16( hTask, hModule );
 262
 263     /* Fill the task structure */
 264
 265     pTask->hSelf = hTask;
 266
 267     pTask->version       = pModule ? pModule->ne_expver : 0x0400;
 268     pTask->hModule       = hModule;
 269     pTask->hParent       = GetCurrentTask();
 270     pTask->magic         = TDB_MAGIC;
 271     pTask->nCmdShow      = cmdShow;
 272
 273     GetCurrentDirectoryA( sizeof(curdir), curdir );
 274     GetShortPathNameA( curdir, curdir, sizeof(curdir) );
 275     pTask->curdrive = (curdir[0] - 'A') | 0x80;
 276     lstrcpynA( pTask->curdir, curdir + 2, sizeof(pTask->curdir) );
 277
 278       /* Create the thunks block */
 279
 280     TASK_CreateThunks( hTask, (char *)pTask->thunks - (char *)pTask, 7 );
 281
 282       /* Copy the module name */
 283
 284     if (hModule)
 285     {
 286         char name[sizeof(pTask->module_name)+1];
 287         size_t len;
 288         GetModuleName16( hModule, name, sizeof(name) );
 289         len = strlen(name) + 1;
 290         memcpy(pTask->module_name, name, min(len,sizeof(pTask->module_name)));
 291         pTask->compat_flags = GetProfileIntA( "Compatibility", name, 0 );
 292     }
 293
 294       /* Allocate a selector for the PDB */
 295
 296     pTask->hPDB = GLOBAL_CreateBlock( GMEM_FIXED, &pTask->pdb, sizeof(PDB16),
 297                                       hModule, LDT_FLAGS_DATA );
 298
 299       /* Fill the PDB */
 300
 301     pTask->pdb.int20 = 0x20cd;
 302     pTask->pdb.dispatcher[0] = 0x9a;  /* ljmp */
 303     proc = GetProcAddress16( GetModuleHandle16("KERNEL"), "DOS3Call" );
 304     memcpy( &pTask->pdb.dispatcher[1], &proc, sizeof(proc) );
 305     pTask->pdb.savedint22 = 0;
 306     pTask->pdb.savedint23 = 0;
 307     pTask->pdb.savedint24 = 0;
 308     pTask->pdb.fileHandlesPtr =
 309         MAKESEGPTR( GlobalHandleToSel16(pTask->hPDB), FIELD_OFFSET( PDB16, fileHandles ));
 310     pTask->pdb.hFileHandles = 0;
 311     memset( pTask->pdb.fileHandles, 0xff, sizeof(pTask->pdb.fileHandles) );
 312     /* FIXME: should we make a copy of the environment? */
 313     pTask->pdb.environment    = SELECTOROF(GetDOSEnvironment16());
 314     pTask->pdb.nbFiles        = 20;
 315
 316     /* Fill the command line */
 317
 318     if (!cmdline)
 319     {
 320         cmdline = GetCommandLineA();
 321         /* remove the first word (program name) */
 322         if (*cmdline == '"')
 323             if (!(cmdline = strchr( cmdline+1, '"' ))) cmdline = GetCommandLineA();
 324         while (*cmdline && (*cmdline != ' ') && (*cmdline != '\t')) cmdline++;
 325         while ((*cmdline == ' ') || (*cmdline == '\t')) cmdline++;
 326         len = strlen(cmdline);
 327     }
 328     if (len >= sizeof(pTask->pdb.cmdLine)) len = sizeof(pTask->pdb.cmdLine)-1;
 329     pTask->pdb.cmdLine[0] = len;
 330     memcpy( pTask->pdb.cmdLine + 1, cmdline, len );
 331     /* pTask->pdb.cmdLine[len+1] = 0; */
 332
 333     TRACE("cmdline='%.*s' task=%04x\n", len, cmdline, hTask );
 334
 335       /* Allocate a code segment alias for the TDB */
 336
 337     pTask->hCSAlias = GLOBAL_CreateBlock( GMEM_FIXED, pTask, sizeof(TDB),
 338                                           pTask->hPDB, LDT_FLAGS_CODE );
 339
 340       /* Default DTA overwrites command line */
 341
 342     pTask->dta = MAKESEGPTR( pTask->hPDB, FIELD_OFFSET( PDB16, cmdLine ));
 343
 344     /* Create scheduler event for 16-bit tasks */
 345
 346     if ( !(pTask->flags & TDBF_WIN32) )
 347         NtCreateEvent( &pTask->hEvent, EVENT_ALL_ACCESS, NULL, NotificationEvent, FALSE );
 348
 349     if (!initial_task) initial_task = hTask;
 350
 351     return pTask;
 352 }
 353
 354
 355 /***********************************************************************
 356  *           TASK_DeleteTask
 357  */
 358 static void TASK_DeleteTask( HTASK16 hTask )
 359 {
 360     TDB *pTask;
 361     HGLOBAL16 hPDB;
 362
 363     if (!(pTask = TASK_GetPtr( hTask ))) return;
 364     hPDB = pTask->hPDB;
 365
 366     pTask->magic = 0xdead; /* invalidate signature */
 367
 368     /* Free the selector aliases */
 369
 370     GLOBAL_FreeBlock( pTask->hCSAlias );
 371     GLOBAL_FreeBlock( pTask->hPDB );
 372
 373     /* Free the task module */
 374
 375     FreeModule16( pTask->hModule );
 376
 377     /* Free the task structure itself */
 378
 379     GlobalFree16( hTask );
 380
 381     /* Free all memory used by this task (including the 32-bit stack, */
 382     /* the environment block and the thunk segments). */
 383
 384     GlobalFreeAll16( hPDB );
 385 }
 386
 387
 388 /***********************************************************************
 389  *           TASK_CreateMainTask
 390  *
 391  * Create a task for the main (32-bit) process.
 392  */
 393 void TASK_CreateMainTask(void)
 394 {
 395     TDB *pTask;
 396     STARTUPINFOA startup_info;
 397     UINT cmdShow = 1; /* SW_SHOWNORMAL but we don't want to include winuser.h here */
 398
 399     GetStartupInfoA( &startup_info );
 400     if (startup_info.dwFlags & STARTF_USESHOWWINDOW) cmdShow = startup_info.wShowWindow;
 401     pTask = TASK_Create( NULL, cmdShow, NULL, 0 );
 402     if (!pTask)
 403     {
 404         ERR("could not create task for main process\n");
 405         ExitProcess(1);
 406     }
 407
 408     pTask->flags        |= TDBF_WIN32;
 409     pTask->hInstance     = 0;
 410     pTask->hPrevInstance = 0;
 411     pTask->teb           = NtCurrentTeb();
 412
 413     /* Add the task to the linked list */
 414     /* (no need to get the win16 lock, we are the only thread at this point) */
 415     TASK_LinkTask( pTask->hSelf );
 416     main_task = pTask->hSelf;
 417 }
 418
 419
 420 struct create_data
 421 {
 422     TDB                 *task;
 423     WIN16_SUBSYSTEM_TIB *tib;
 424 };
 425
 426 /* allocate the win16 TIB for a new 16-bit task */
 427 static WIN16_SUBSYSTEM_TIB *allocate_win16_tib( TDB *pTask )
 428 {
 429     WCHAR path[MAX_PATH];
 430     WIN16_SUBSYSTEM_TIB *tib;
 431     UNICODE_STRING *curdir;
 432     NE_MODULE *pModule = NE_GetPtr( pTask->hModule );
 433
 434     if (!(tib = HeapAlloc( GetProcessHeap(), 0, sizeof(*tib) ))) return NULL;
 435     MultiByteToWideChar( CP_ACP, 0, NE_MODULE_NAME(pModule), -1, path, MAX_PATH );
 436     GetLongPathNameW( path, path, MAX_PATH );
 437     if (RtlCreateUnicodeString( &tib->exe_str, path )) tib->exe_name = &tib->exe_str;
 438     else tib->exe_name = NULL;
 439
 440     RtlAcquirePebLock();
 441     if (NtCurrentTeb()->Tib.SubSystemTib)
 442         curdir = &((WIN16_SUBSYSTEM_TIB *)NtCurrentTeb()->Tib.SubSystemTib)->curdir.DosPath;
 443     else
 444         curdir = &NtCurrentTeb()->Peb->ProcessParameters->CurrentDirectory.DosPath;
 445     tib->curdir.DosPath.MaximumLength = sizeof(tib->curdir_buffer);
 446     tib->curdir.DosPath.Length = min( curdir->Length, tib->curdir.DosPath.MaximumLength-sizeof(WCHAR) );
 447     tib->curdir.DosPath.Buffer = tib->curdir_buffer;
 448     tib->curdir.Handle = 0;
 449     memcpy( tib->curdir_buffer, curdir->Buffer, tib->curdir.DosPath.Length );
 450     tib->curdir_buffer[tib->curdir.DosPath.Length/sizeof(WCHAR)] = 0;
 451     RtlReleasePebLock();
 452     return tib;
 453 }
 454
 455 static inline void free_win16_tib( WIN16_SUBSYSTEM_TIB *tib )
 456 {
 457     if (tib->exe_name) RtlFreeUnicodeString( tib->exe_name );
 458     HeapFree( GetProcessHeap(), 0, tib );
 459 }
 460
 461 /* startup routine for a new 16-bit thread */
 462 static DWORD CALLBACK task_start( LPVOID p )
 463 {
 464     struct create_data *data = p;
 465     TDB *pTask = data->task;
 466     DWORD ret;
 467
 468     kernel_get_thread_data()->htask16 = pTask->hSelf;
 469     NtCurrentTeb()->Tib.SubSystemTib = data->tib;
 470     HeapFree( GetProcessHeap(), 0, data );
 471
 472     _EnterWin16Lock();
 473     TASK_LinkTask( pTask->hSelf );
 474     pTask->teb = NtCurrentTeb();
 475     ret = NE_StartTask();
 476     _LeaveWin16Lock();
 477     return ret;
 478 }
 479
 480
 481 /***********************************************************************
 482  *           TASK_SpawnTask
 483  *
 484  * Spawn a new 16-bit task.
 485  */
 486 HTASK16 TASK_SpawnTask( NE_MODULE *pModule, WORD cmdShow,
 487                         LPCSTR cmdline, BYTE len, HANDLE *hThread )
 488 {
 489     struct create_data *data = NULL;
 490     WIN16_SUBSYSTEM_TIB *tib;
 491     TDB *pTask;
 492
 493     if (!(pTask = TASK_Create( pModule, cmdShow, cmdline, len ))) return 0;
 494     if (!(tib = allocate_win16_tib( pTask ))) goto failed;
 495     if (!(data = HeapAlloc( GetProcessHeap(), 0, sizeof(*data)))) goto failed;
 496     data->task = pTask;
 497     data->tib = tib;
 498     if (!(*hThread = CreateThread( NULL, 0, task_start, data, 0, NULL ))) goto failed;
 499     return pTask->hSelf;
 500
 501 failed:
 502     if (tib) free_win16_tib( tib );
 503     HeapFree( GetProcessHeap(), 0, data );
 504     TASK_DeleteTask( pTask->hSelf );
 505     return 0;
 506 }
 507
 508
 509 /***********************************************************************
 510  *           TASK_GetTaskFromThread
 511  */
 512 HTASK16 TASK_GetTaskFromThread( DWORD thread )
 513 {
 514     TDB *p = TASK_GetPtr( hFirstTask );
 515     while (p)
 516     {
 517         if (p->teb->ClientId.UniqueThread == (HANDLE)thread) return p->hSelf;
 518         p = TASK_GetPtr( p->hNext );
 519     }
 520     return 0;
 521 }
 522
 523
 524 /***********************************************************************
 525  *           TASK_CallTaskSignalProc
 526  */
 527 static void TASK_CallTaskSignalProc( UINT16 uCode, HANDLE16 hTaskOrModule )
 528 {
 529     WORD args[5];
 530     TDB *pTask = TASK_GetCurrent();
 531
 532     if ( !pTask || !pTask->userhandler ) return;
 533
 534     args[4] = hTaskOrModule;
 535     args[3] = uCode;
 536     args[2] = 0;
 537     args[1] = pTask->hInstance;
 538     args[0] = pTask->hQueue;
 539     WOWCallback16Ex( (DWORD)pTask->userhandler, WCB16_PASCAL, sizeof(args), args, NULL );
 540 }
 541
 542
 543 /***********************************************************************
 544  *           TASK_ExitTask
 545  */
 546 void TASK_ExitTask(void)
 547 {
 548     WIN16_SUBSYSTEM_TIB *tib;
 549     TDB *pTask;
 550     DWORD lockCount;
 551
 552     pTask = TASK_GetCurrent();
 553     if (!pTask) return;
 554
 555     TRACE("Killing task %04x\n", pTask->hSelf );
 556
 557     /* Perform USER cleanup */
 558
 559     TASK_CallTaskSignalProc( USIG16_TERMINATION, pTask->hSelf );
 560
 561     /* Remove the task from the list to be sure we never switch back to it */
 562     TASK_UnlinkTask( pTask->hSelf );
 563
 564     if (!nTaskCount || (nTaskCount == 1 && hFirstTask == initial_task))
 565     {
 566         TRACE("this is the last task, exiting\n" );
 567         ExitKernel16();
 568     }
 569
 570     pTask->nEvents = 0;
 571
 572     if ( hLockedTask == pTask->hSelf )
 573         hLockedTask = 0;
 574
 575     TASK_DeleteTask( pTask->hSelf );
 576
 577     if ((tib = NtCurrentTeb()->Tib.SubSystemTib))
 578     {
 579         free_win16_tib( tib );
 580         NtCurrentTeb()->Tib.SubSystemTib = NULL;
 581     }
 582
 583     /* ... and completely release the Win16Lock, just in case. */
 584     ReleaseThunkLock( &lockCount );
 585 }
 586
 587
 588 /***********************************************************************
 589  *           ExitKernel (KERNEL.2)
 590  *
 591  * Clean-up everything and exit the Wine process.
 592  */
 593 void WINAPI ExitKernel16(void)
 594 {
 595     WriteOutProfiles16();
 596     TerminateProcess( GetCurrentProcess(), 0 );
 597 }
 598
 599
 600 /***********************************************************************
 601  *           InitTask  (KERNEL.91)
 602  *
 603  * Called by the application startup code.
 604  */
 605 void WINAPI InitTask16( CONTEXT *context )
 606 {
 607     TDB *pTask;
 608     INSTANCEDATA *pinstance;
 609     SEGPTR ptr;
 610
 611     context->Eax = 0;
 612     if (!(pTask = TASK_GetCurrent())) return;
 613
 614     /* Note: we need to trust that BX/CX contain the stack/heap sizes,
 615        as some apps, notably Visual Basic apps, *modify* the heap/stack
 616        size of the instance data segment before calling InitTask() */
 617
 618     /* Initialize the INSTANCEDATA structure */
 619     pinstance = MapSL( MAKESEGPTR(CURRENT_DS, 0) );
 620     pinstance->stackmin    = CURRENT_SP + sizeof( STACK16FRAME );
 621     pinstance->stackbottom = pinstance->stackmin; /* yup, that's right. Confused me too. */
 622     pinstance->stacktop    = ( pinstance->stackmin > LOWORD(context->Ebx) ?
 623                                pinstance->stackmin - LOWORD(context->Ebx) : 0 ) + 150;
 624
 625     /* Initialize the local heap */
 626     if (LOWORD(context->Ecx))
 627         LocalInit16( GlobalHandleToSel16(pTask->hInstance), 0, LOWORD(context->Ecx) );
 628
 629     /* Initialize implicitly loaded DLLs */
 630     NE_InitializeDLLs( pTask->hModule );
 631     NE_DllProcessAttach( pTask->hModule );
 632
 633     /* Registers on return are:
 634      * ax     1 if OK, 0 on error
 635      * cx     stack limit in bytes
 636      * dx     cmdShow parameter
 637      * si     instance handle of the previous instance
 638      * di     instance handle of the new task
 639      * es:bx  pointer to command line inside PSP
 640      *
 641      * 0 (=%bp) is pushed on the stack
 642      */
 643     ptr = stack16_push( sizeof(WORD) );
 644     *(WORD *)MapSL(ptr) = 0;
 645     context->Esp -= 2;
 646
 647     context->Eax = 1;
 648
 649     if (!pTask->pdb.cmdLine[0]) context->Ebx = 0x80;
 650     else
 651     {
 652         LPBYTE p = &pTask->pdb.cmdLine[1];
 653         while ((*p == ' ') || (*p == '\t')) p++;
 654         context->Ebx = 0x80 + (p - pTask->pdb.cmdLine);
 655     }
 656     context->Ecx   = pinstance->stacktop;
 657     context->Edx   = pTask->nCmdShow;
 658     context->Esi   = (DWORD)pTask->hPrevInstance;
 659     context->Edi   = (DWORD)pTask->hInstance;
 660     context->SegEs = (WORD)pTask->hPDB;
 661 }
 662
 663
 664 /***********************************************************************
 665  *           WaitEvent  (KERNEL.30)
 666  */
 667 BOOL16 WINAPI WaitEvent16( HTASK16 hTask )
 668 {
 669     TDB *pTask;
 670
 671     if (!hTask) hTask = GetCurrentTask();
 672     pTask = TASK_GetPtr( hTask );
 673
 674     if (pTask->flags & TDBF_WIN32)
 675     {
 676         FIXME("called for Win32 thread (%04lx)!\n", GetCurrentThreadId());
 677         return TRUE;
 678     }
 679
 680     if (pTask->nEvents > 0)
 681     {
 682         pTask->nEvents--;
 683         return FALSE;
 684     }
 685
 686     if (pTask->teb == NtCurrentTeb())
 687     {
 688         DWORD lockCount;
 689
 690         NtResetEvent( pTask->hEvent, NULL );
 691         ReleaseThunkLock( &lockCount );
 692         SYSLEVEL_CheckNotLevel( 1 );
 693         WaitForSingleObject( pTask->hEvent, INFINITE );
 694         RestoreThunkLock( lockCount );
 695         if (pTask->nEvents > 0) pTask->nEvents--;
 696     }
 697     else FIXME("for other task %04x cur=%04x\n",pTask->hSelf,GetCurrentTask());
 698
 699     return TRUE;
 700 }
 701
 702
 703 /***********************************************************************
 704  *           PostEvent  (KERNEL.31)
 705  */
 706 void WINAPI PostEvent16( HTASK16 hTask )
 707 {
 708     TDB *pTask;
 709
 710     if (!hTask) hTask = GetCurrentTask();
 711     if (!(pTask = TASK_GetPtr( hTask ))) return;
 712
 713     if (pTask->flags & TDBF_WIN32)
 714     {
 715         FIXME("called for Win32 thread (%04lx)!\n", (DWORD)pTask->teb->ClientId.UniqueThread );
 716         return;
 717     }
 718
 719     pTask->nEvents++;
 720
 721     if (pTask->nEvents == 1) NtSetEvent( pTask->hEvent, NULL );
 722 }
 723
 724
 725 /***********************************************************************
 726  *           SetPriority  (KERNEL.32)
 727  */
 728 void WINAPI SetPriority16( HTASK16 hTask, INT16 delta )
 729 {
 730     TDB *pTask;
 731     INT16 newpriority;
 732
 733     if (!hTask) hTask = GetCurrentTask();
 734     if (!(pTask = TASK_GetPtr( hTask ))) return;
 735     newpriority = pTask->priority + delta;
 736     if (newpriority < -32) newpriority = -32;
 737     else if (newpriority > 15) newpriority = 15;
 738
 739     pTask->priority = newpriority + 1;
 740     TASK_UnlinkTask( pTask->hSelf );
 741     TASK_LinkTask( pTask->hSelf );
 742     pTask->priority--;
 743 }
 744
 745
 746 /***********************************************************************
 747  *           LockCurrentTask  (KERNEL.33)
 748  */
 749 HTASK16 WINAPI LockCurrentTask16( BOOL16 bLock )
 750 {
 751     if (bLock) hLockedTask = GetCurrentTask();
 752     else hLockedTask = 0;
 753     return hLockedTask;
 754 }
 755
 756
 757 /***********************************************************************
 758  *           IsTaskLocked  (KERNEL.122)
 759  */
 760 HTASK16 WINAPI IsTaskLocked16(void)
 761 {
 762     return hLockedTask;
 763 }
 764
 765
 766 /***********************************************************************
 767  *           OldYield  (KERNEL.117)
 768  */
 769 void WINAPI OldYield16(void)
 770 {
 771    DWORD count;
 772
 773    ReleaseThunkLock(&count);
 774    RestoreThunkLock(count);
 775 }
 776
 777 /***********************************************************************
 778  *           WIN32_OldYield  (KERNEL.447)
 779  */
 780 void WINAPI WIN32_OldYield16(void)
 781 {
 782    DWORD count;
 783
 784    ReleaseThunkLock(&count);
 785    RestoreThunkLock(count);
 786 }
 787
 788 /***********************************************************************
 789  *           DirectedYield  (KERNEL.150)
 790  */
 791 void WINAPI DirectedYield16( HTASK16 hTask )
 792 {
 793     OldYield16();
 794 }
 795
 796 /***********************************************************************
 797  *           Yield  (KERNEL.29)
 798  */
 799 void WINAPI Yield16(void)
 800 {
 801     TDB *pCurTask = TASK_GetCurrent();
 802
 803     if (pCurTask && pCurTask->hQueue)
 804     {
 805         HMODULE mod = GetModuleHandleA( "user32.dll" );
 806         if (mod)
 807         {
 808             BOOL (WINAPI *pPeekMessageW)( MSG *msg, HWND hwnd, UINT first, UINT last, UINT flags );
 809             pPeekMessageW = (void *)GetProcAddress( mod, "PeekMessageW" );
 810             if (pPeekMessageW)
 811             {
 812                 MSG msg;
 813                 pPeekMessageW( &msg, 0, 0, 0, PM_REMOVE | PM_QS_SENDMESSAGE );
 814                 return;
 815             }
 816         }
 817     }
 818     OldYield16();
 819 }
 820
 821 /***********************************************************************
 822  *           KERNEL_490  (KERNEL.490)
 823  */
 824 HTASK16 WINAPI KERNEL_490( HTASK16 someTask )
 825 {
 826     if ( !someTask ) return 0;
 827
 828     FIXME("(%04x): stub\n", someTask );
 829     return 0;
 830 }
 831
 832 /***********************************************************************
 833  *           MakeProcInstance  (KERNEL.51)
 834  */
 835 FARPROC16 WINAPI MakeProcInstance16( FARPROC16 func, HANDLE16 hInstance )
 836 {
 837     struct thunk *thunk;
 838     BYTE *lfunc;
 839     SEGPTR thunkaddr;
 840     WORD hInstanceSelector;
 841
 842     hInstanceSelector = GlobalHandleToSel16(hInstance);
 843
 844     TRACE("(%p, %04x);\n", func, hInstance);
 845
 846     if (!HIWORD(func)) {
 847       /* Win95 actually protects via SEH, but this is better for debugging */
 848       WARN("Ouch ! Called with invalid func %p !\n", func);
 849       return NULL;
 850     }
 851
 852     if ( (GlobalHandleToSel16(CURRENT_DS) != hInstanceSelector)
 853       && (hInstance != 0)
 854       && (hInstance != 0xffff) )
 855     {
 856         /* calling MPI with a foreign DSEG is invalid ! */
 857         WARN("Problem with hInstance? Got %04x, using %04x instead\n",
 858                    hInstance,CURRENT_DS);
 859     }
 860
 861     /* Always use the DSEG that MPI was entered with.
 862      * We used to set hInstance to GetTaskDS16(), but this should be wrong
 863      * as CURRENT_DS provides the DSEG value we need.
 864      * ("calling" DS, *not* "task" DS !) */
 865     hInstanceSelector = CURRENT_DS;
 866     hInstance = GlobalHandle16(hInstanceSelector);
 867
 868     /* no thunking for DLLs */
 869     if (NE_GetPtr(FarGetOwner16(hInstance))->ne_flags & NE_FFLAGS_LIBMODULE)
 870         return func;
 871
 872     thunkaddr = TASK_AllocThunk();
 873     if (!thunkaddr) return NULL;
 874     thunk = MapSL( thunkaddr );
 875     lfunc = MapSL( (SEGPTR)func );
 876
 877     TRACE("(%p,%04x): got thunk %08lx\n", func, hInstance, thunkaddr );
 878     if (((lfunc[0]==0x8c) && (lfunc[1]==0xd8)) || /* movw %ds, %ax */
 879         ((lfunc[0]==0x1e) && (lfunc[1]==0x58))    /* pushw %ds, popw %ax */
 880     ) {
 881         WARN("This was the (in)famous \"thunk useless\" warning. We thought we have to overwrite with nop;nop;, but this isn't true.\n");
 882     }
 883
 884     thunk->movw     = 0xb8;    /* movw instance, %ax */
 885     thunk->instance = hInstanceSelector;
 886     thunk->ljmp     = 0xea;    /* ljmp func */
 887     thunk->func     = func;
 888     return (FARPROC16)thunkaddr;
 889     /* CX reg indicates if thunkaddr != NULL, implement if needed */
 890 }
 891
 892
 893 /***********************************************************************
 894  *           FreeProcInstance  (KERNEL.52)
 895  */
 896 void WINAPI FreeProcInstance16( FARPROC16 func )
 897 {
 898     TRACE("(%p)\n", func );
 899     TASK_FreeThunk( (SEGPTR)func );
 900 }
 901
 902 /**********************************************************************
 903  *          TASK_GetCodeSegment
 904  *
 905  * Helper function for GetCodeHandle/GetCodeInfo: Retrieve the module
 906  * and logical segment number of a given code segment.
 907  *
 908  * 'proc' either *is* already a pair of module handle and segment number,
 909  * in which case there's nothing to do.  Otherwise, it is a pointer to
 910  * a function, and we need to retrieve the code segment.  If the pointer
 911  * happens to point to a thunk, we'll retrieve info about the code segment
 912  * where the function pointed to by the thunk resides, not the thunk itself.
 913  *
 914  * FIXME: if 'proc' is a SNOOP16 return stub, we should retrieve info about
 915  *        the function the snoop code will return to ...
 916  *
 917  */
 918 static BOOL TASK_GetCodeSegment( FARPROC16 proc, NE_MODULE **ppModule,
 919                                  SEGTABLEENTRY **ppSeg, int *pSegNr )
 920 {
 921     NE_MODULE *pModule = NULL;
 922     SEGTABLEENTRY *pSeg = NULL;
 923     int segNr=0;
 924
 925     /* Try pair of module handle / segment number */
 926     pModule = GlobalLock16( HIWORD( proc ) );
 927     if ( pModule && pModule->ne_magic == IMAGE_OS2_SIGNATURE )
 928     {
 929         segNr = LOWORD( proc );
 930         if ( segNr && segNr <= pModule->ne_cseg )
 931             pSeg = NE_SEG_TABLE( pModule ) + segNr-1;
 932     }
 933
 934     /* Try thunk or function */
 935     else
 936     {
 937         BYTE *thunk = MapSL( (SEGPTR)proc );
 938         WORD selector;
 939
 940         if ((thunk[0] == 0xb8) && (thunk[3] == 0xea))
 941             selector = thunk[6] + (thunk[7] << 8);
 942         else
 943             selector = HIWORD( proc );
 944
 945         pModule = NE_GetPtr( GlobalHandle16( selector ) );
 946         pSeg = pModule? NE_SEG_TABLE( pModule ) : NULL;
 947
 948         if ( pModule )
 949             for ( segNr = 1; segNr <= pModule->ne_cseg; segNr++, pSeg++ )
 950                 if ( GlobalHandleToSel16(pSeg->hSeg) == selector )
 951                     break;
 952
 953         if ( pModule && segNr > pModule->ne_cseg )
 954             pSeg = NULL;
 955     }
 956
 957     /* Abort if segment not found */
 958
 959     if ( !pModule || !pSeg )
 960         return FALSE;
 961
 962     /* Return segment data */
 963
 964     if ( ppModule ) *ppModule = pModule;
 965     if ( ppSeg    ) *ppSeg    = pSeg;
 966     if ( pSegNr   ) *pSegNr   = segNr;
 967
 968     return TRUE;
 969 }
 970
 971 /**********************************************************************
 972  *          GetCodeHandle    (KERNEL.93)
 973  */
 974 DWORD WINAPI GetCodeHandle16( FARPROC16 proc )
 975 {
 976     SEGTABLEENTRY *pSeg;
 977
 978     if ( !TASK_GetCodeSegment( proc, NULL, &pSeg, NULL ) )
 979         return 0;
 980
 981     return MAKELONG( pSeg->hSeg, GlobalHandleToSel16(pSeg->hSeg) );
 982 }
 983
 984 /**********************************************************************
 985  *          GetCodeInfo    (KERNEL.104)
 986  */
 987 BOOL16 WINAPI GetCodeInfo16( FARPROC16 proc, SEGINFO *segInfo )
 988 {
 989     NE_MODULE *pModule;
 990     SEGTABLEENTRY *pSeg;
 991     int segNr;
 992
 993     if ( !TASK_GetCodeSegment( proc, &pModule, &pSeg, &segNr ) )
 994         return FALSE;
 995
 996     /* Fill in segment information */
 997
 998     segInfo->offSegment = pSeg->filepos;
 999     segInfo->cbSegment  = pSeg->size;
1000     segInfo->flags      = pSeg->flags;
1001     segInfo->cbAlloc    = pSeg->minsize;
1002     segInfo->h          = pSeg->hSeg;
1003     segInfo->alignShift = pModule->ne_align;
1004
1005     if ( segNr == pModule->ne_autodata )
1006         segInfo->cbAlloc += pModule->ne_heap + pModule->ne_stack;
1007
1008     /* Return module handle in %es */
1009
1010     CURRENT_STACK16->es = GlobalHandleToSel16( pModule->self );
1011
1012     return TRUE;
1013 }
1014
1015
1016 /**********************************************************************
1017  *          DefineHandleTable    (KERNEL.94)
1018  */
1019 BOOL16 WINAPI DefineHandleTable16( WORD wOffset )
1020 {
1021     FIXME("(%04x): stub ?\n", wOffset);
1022     return TRUE;
1023 }
1024
1025
1026 /***********************************************************************
1027  *           SetTaskQueue  (KERNEL.34)
1028  */
1029 HQUEUE16 WINAPI SetTaskQueue16( HTASK16 hTask, HQUEUE16 hQueue )
1030 {
1031     FIXME( "stub, should not get called\n" );
1032     return 0xbeef;
1033 }
1034
1035
1036 /***********************************************************************
1037  *           GetTaskQueue  (KERNEL.35)
1038  */
1039 HQUEUE16 WINAPI GetTaskQueue16( HTASK16 hTask )
1040 {
1041     FIXME( "stub, should not get called\n" );
1042     return 0xbeef;
1043 }
1044
1045 /***********************************************************************
1046  *           SetThreadQueue  (KERNEL.463)
1047  */
1048 HQUEUE16 WINAPI SetThreadQueue16( DWORD thread, HQUEUE16 hQueue )
1049 {
1050     FIXME( "stub, should not get called\n" );
1051     return 0xbeef;
1052 }
1053
1054 /***********************************************************************
1055  *           GetThreadQueue  (KERNEL.464)
1056  */
1057 HQUEUE16 WINAPI GetThreadQueue16( DWORD thread )
1058 {
1059     FIXME( "stub, should not get called\n" );
1060     return 0xbeef;
1061 }
1062
1063 /***********************************************************************
1064  *           SetFastQueue  (KERNEL.624)
1065  */
1066 VOID WINAPI SetFastQueue16( DWORD thread, HQUEUE16 hQueue )
1067 {
1068     FIXME( "stub, should not get called\n" );
1069 }
1070
1071 /***********************************************************************
1072  *           GetFastQueue  (KERNEL.625)
1073  */
1074 HQUEUE16 WINAPI GetFastQueue16( void )
1075 {
1076     FIXME( "stub, should not get called\n" );
1077     return 0xbeef;
1078 }
1079
1080 /***********************************************************************
1081  *           SwitchStackTo   (KERNEL.108)
1082  */
1083 void WINAPI SwitchStackTo16( WORD seg, WORD ptr, WORD top )
1084 {
1085     STACK16FRAME *oldFrame, *newFrame;
1086     INSTANCEDATA *pData;
1087     UINT16 copySize;
1088
1089     if (!(pData = GlobalLock16( seg ))) return;
1090     TRACE( "old=%04x:%04x new=%04x:%04x\n", CURRENT_SS, CURRENT_SP, seg, ptr );
1091
1092     /* Save the old stack */
1093
1094     oldFrame = CURRENT_STACK16;
1095     /* pop frame + args and push bp */
1096     pData->old_ss = CURRENT_SS;
1097     pData->old_sp = CURRENT_SP + sizeof(STACK16FRAME) + 2 * sizeof(WORD);
1098     *(WORD *)MapSL(MAKESEGPTR(pData->old_ss, pData->old_sp)) = oldFrame->bp;
1099     pData->stacktop    = top;
1100     pData->stackmin    = ptr;
1101     pData->stackbottom = ptr;
1102
1103     /* Switch to the new stack */
1104
1105     /* Note: we need to take the 3 arguments into account; otherwise,
1106      * the stack will underflow upon return from this function.
1107      */
1108     copySize = oldFrame->bp - pData->old_sp;
1109     copySize += 3 * sizeof(WORD) + sizeof(STACK16FRAME);
1110     CURRENT_SS = seg;
1111     CURRENT_SP = ptr - copySize;
1112     newFrame = CURRENT_STACK16;
1113
1114     /* Copy the stack frame and the local variables to the new stack */
1115
1116     memmove( newFrame, oldFrame, copySize );
1117     newFrame->bp = ptr;
1118     *(WORD *)MapSL( MAKESEGPTR( seg, ptr ) ) = 0;  /* clear previous bp */
1119 }
1120
1121
1122 /***********************************************************************
1123  *           SwitchStackBack   (KERNEL.109)
1124  */
1125 void WINAPI SwitchStackBack16( CONTEXT *context )
1126 {
1127     STACK16FRAME *oldFrame, *newFrame;
1128     INSTANCEDATA *pData;
1129
1130     if (!(pData = GlobalLock16(CURRENT_SS)))
1131         return;
1132     if (!pData->old_ss)
1133     {
1134         WARN("No previous SwitchStackTo\n" );
1135         return;
1136     }
1137     TRACE( "restoring stack %04x:%04x\n", pData->old_ss, pData->old_sp );
1138
1139     oldFrame = CURRENT_STACK16;
1140
1141     /* Pop bp from the previous stack */
1142
1143     context->Ebp = (context->Ebp & ~0xffff) | *(WORD *)MapSL(MAKESEGPTR(pData->old_ss, pData->old_sp));
1144     pData->old_sp += sizeof(WORD);
1145
1146     /* Switch back to the old stack */
1147
1148     CURRENT_SS = pData->old_ss;
1149     CURRENT_SP = pData->old_sp - sizeof(STACK16FRAME);
1150     context->SegSs = pData->old_ss;
1151     context->Esp   = pData->old_sp - sizeof(DWORD); /*ret addr*/
1152     pData->old_ss = pData->old_sp = 0;
1153
1154     /* Build a stack frame for the return */
1155
1156     newFrame = CURRENT_STACK16;
1157     newFrame->frame32     = oldFrame->frame32;
1158     newFrame->module_cs   = oldFrame->module_cs;
1159     newFrame->callfrom_ip = oldFrame->callfrom_ip;
1160     newFrame->entry_ip    = oldFrame->entry_ip;
1161 }
1162
1163
1164 /***********************************************************************
1165  *           GetTaskQueueDS  (KERNEL.118)
1166  */
1167 void WINAPI GetTaskQueueDS16(void)
1168 {
1169     CURRENT_STACK16->ds = GlobalHandleToSel16( GetTaskQueue16(0) );
1170 }
1171
1172
1173 /***********************************************************************
1174  *           GetTaskQueueES  (KERNEL.119)
1175  */
1176 void WINAPI GetTaskQueueES16(void)
1177 {
1178     CURRENT_STACK16->es = GlobalHandleToSel16( GetTaskQueue16(0) );
1179 }
1180
1181
1182 /***********************************************************************
1183  *           GetCurrentTask   (KERNEL32.@)
1184  */
1185 HTASK16 WINAPI GetCurrentTask(void)
1186 {
1187     HTASK16 ret = kernel_get_thread_data()->htask16;
1188     if (!ret) ret = main_task;
1189     return ret;
1190 }
1191
1192 /***********************************************************************
1193  *           GetCurrentTask   (KERNEL.36)
1194  */
1195 DWORD WINAPI WIN16_GetCurrentTask(void)
1196 {
1197     /* This is the version used by relay code; the first task is */
1198     /* returned in the high word of the result */
1199     return MAKELONG( GetCurrentTask(), hFirstTask );
1200 }
1201
1202
1203 /***********************************************************************
1204  *           GetCurrentPDB   (KERNEL.37)
1205  *
1206  * UNDOC: returns PSP of KERNEL in high word
1207  */
1208 DWORD WINAPI GetCurrentPDB16(void)
1209 {
1210     TDB *pTask;
1211
1212     if (!(pTask = TASK_GetCurrent())) return 0;
1213     return MAKELONG(pTask->hPDB, 0); /* FIXME */
1214 }
1215
1216
1217 /***********************************************************************
1218  *           GetCurPID   (KERNEL.157)
1219  */
1220 DWORD WINAPI GetCurPID16( DWORD unused )
1221 {
1222     return 0;
1223 }
1224
1225
1226 /***********************************************************************
1227  *           GetInstanceData   (KERNEL.54)
1228  */
1229 INT16 WINAPI GetInstanceData16( HINSTANCE16 instance, WORD buffer, INT16 len )
1230 {
1231     char *ptr = GlobalLock16( instance );
1232     if (!ptr || !len) return 0;
1233     if ((int)buffer + len >= 0x10000) len = 0x10000 - buffer;
1234     memcpy( (char *)GlobalLock16(CURRENT_DS) + buffer, ptr + buffer, len );
1235     return len;
1236 }
1237
1238
1239 /***********************************************************************
1240  *           GetExeVersion   (KERNEL.105)
1241  */
1242 WORD WINAPI GetExeVersion16(void)
1243 {
1244     TDB *pTask;
1245
1246     if (!(pTask = TASK_GetCurrent())) return 0;
1247     return pTask->version;
1248 }
1249
1250
1251 /***********************************************************************
1252  *           GetLPErrMode   (KERNEL.99)
1253  */
1254 SEGPTR WINAPI GetLPErrMode(void)
1255 {
1256     FIXME("(): stub\n");
1257     return 0;
1258 }
1259
1260
1261 /***********************************************************************
1262  *           SetErrorMode   (KERNEL.107)
1263  */
1264 UINT16 WINAPI SetErrorMode16( UINT16 mode )
1265 {
1266     TDB *pTask;
1267     if (!(pTask = TASK_GetCurrent())) return 0;
1268     pTask->error_mode = mode;
1269     return SetErrorMode( mode );
1270 }
1271
1272
1273 /***********************************************************************
1274  *           GetNumTasks   (KERNEL.152)
1275  */
1276 UINT16 WINAPI GetNumTasks16(void)
1277 {
1278     return nTaskCount;
1279 }
1280
1281
1282 /***********************************************************************
1283  *           GetTaskDS   (KERNEL.155)
1284  *
1285  * Note: this function apparently returns a DWORD with LOWORD == HIWORD.
1286  * I don't think we need to bother with this.
1287  */
1288 HINSTANCE16 WINAPI GetTaskDS16(void)
1289 {
1290     TDB *pTask;
1291
1292     if (!(pTask = TASK_GetCurrent())) return 0;
1293     return GlobalHandleToSel16(pTask->hInstance);
1294 }
1295
1296 /***********************************************************************
1297  *           GetDummyModuleHandleDS   (KERNEL.602)
1298  */
1299 WORD WINAPI GetDummyModuleHandleDS16(void)
1300 {
1301     TDB *pTask;
1302     WORD selector;
1303
1304     if (!(pTask = TASK_GetCurrent())) return 0;
1305     if (!(pTask->flags & TDBF_WIN32)) return 0;
1306     selector = GlobalHandleToSel16( pTask->hModule );
1307     CURRENT_DS = selector;
1308     return selector;
1309 }
1310
1311 /***********************************************************************
1312  *           IsTask   (KERNEL.320)
1313  */
1314 BOOL16 WINAPI IsTask16( HTASK16 hTask )
1315 {
1316     TDB *pTask;
1317
1318     if (!(pTask = TASK_GetPtr( hTask ))) return FALSE;
1319     if (GlobalSize16( hTask ) < sizeof(TDB)) return FALSE;
1320     return (pTask->magic == TDB_MAGIC);
1321 }
1322
1323
1324 /***********************************************************************
1325  *           IsWinOldApTask   (KERNEL.158)
1326  */
1327 BOOL16 WINAPI IsWinOldApTask16( HTASK16 hTask )
1328 {
1329     /* should return bit 0 of byte 0x48 in PSP */
1330     return FALSE;
1331 }
1332
1333 /***********************************************************************
1334  *           SetTaskSignalProc   (KERNEL.38)
1335  */
1336 FARPROC16 WINAPI SetTaskSignalProc( HTASK16 hTask, FARPROC16 proc )
1337 {
1338     TDB *pTask;
1339     FARPROC16 oldProc;
1340
1341     if (!hTask) hTask = GetCurrentTask();
1342     if (!(pTask = TASK_GetPtr( hTask ))) return NULL;
1343     oldProc = pTask->userhandler;
1344     pTask->userhandler = proc;
1345     return oldProc;
1346 }
1347
1348 /***********************************************************************
1349  *           SetSigHandler   (KERNEL.140)
1350  */
1351 WORD WINAPI SetSigHandler16( FARPROC16 newhandler, FARPROC16* oldhandler,
1352                            UINT16 *oldmode, UINT16 newmode, UINT16 flag )
1353 {
1354     FIXME("(%p,%p,%p,%d,%d), unimplemented.\n",
1355           newhandler,oldhandler,oldmode,newmode,flag );
1356
1357     if (flag != 1) return 0;
1358     if (!newmode) newhandler = NULL;  /* Default handler */
1359     if (newmode != 4)
1360     {
1361         TDB *pTask;
1362
1363         if (!(pTask = TASK_GetCurrent())) return 0;
1364         if (oldmode) *oldmode = pTask->signal_flags;
1365         pTask->signal_flags = newmode;
1366         if (oldhandler) *oldhandler = pTask->sighandler;
1367         pTask->sighandler = newhandler;
1368     }
1369     return 0;
1370 }
1371
1372
1373 /***********************************************************************
1374  *           GlobalNotify   (KERNEL.154)
1375  *
1376  * Note that GlobalNotify does _not_ return the old NotifyProc
1377  * -- contrary to LocalNotify !!
1378  */
1379 VOID WINAPI GlobalNotify16( FARPROC16 proc )
1380 {
1381     TDB *pTask;
1382
1383     if (!(pTask = TASK_GetCurrent())) return;
1384     pTask->discardhandler = proc;
1385 }
1386
1387
1388 /***********************************************************************
1389  *           GetExePtrHelper
1390  */
1391 static inline HMODULE16 GetExePtrHelper( HANDLE16 handle, HTASK16 *hTask )
1392 {
1393     char *ptr;
1394     HANDLE16 owner;
1395
1396       /* Check for module handle */
1397
1398     if (!(ptr = GlobalLock16( handle ))) return 0;
1399     if (((NE_MODULE *)ptr)->ne_magic == IMAGE_OS2_SIGNATURE) return handle;
1400
1401       /* Search for this handle inside all tasks */
1402
1403     *hTask = hFirstTask;
1404     while (*hTask)
1405     {
1406         TDB *pTask = TASK_GetPtr( *hTask );
1407         if ((*hTask == handle) ||
1408             (pTask->hInstance == handle) ||
1409             (pTask->hQueue == handle) ||
1410             (pTask->hPDB == handle)) return pTask->hModule;
1411         *hTask = pTask->hNext;
1412     }
1413
1414       /* Check the owner for module handle */
1415
1416     owner = FarGetOwner16( handle );
1417     if (!(ptr = GlobalLock16( owner ))) return 0;
1418     if (((NE_MODULE *)ptr)->ne_magic == IMAGE_OS2_SIGNATURE) return owner;
1419
1420       /* Search for the owner inside all tasks */
1421
1422     *hTask = hFirstTask;
1423     while (*hTask)
1424     {
1425         TDB *pTask = TASK_GetPtr( *hTask );
1426         if ((*hTask == owner) ||
1427             (pTask->hInstance == owner) ||
1428             (pTask->hQueue == owner) ||
1429             (pTask->hPDB == owner)) return pTask->hModule;
1430         *hTask = pTask->hNext;
1431     }
1432
1433     return 0;
1434 }
1435
1436 /***********************************************************************
1437  *           GetExePtr   (KERNEL.133)
1438  */
1439 HMODULE16 WINAPI WIN16_GetExePtr( HANDLE16 handle )
1440 {
1441     HTASK16 hTask = 0;
1442     HMODULE16 hModule = GetExePtrHelper( handle, &hTask );
1443     STACK16FRAME *frame = CURRENT_STACK16;
1444     frame->ecx = hModule;
1445     if (hTask) frame->es = hTask;
1446     return hModule;
1447 }
1448
1449
1450 /***********************************************************************
1451  *           K228   (KERNEL.228)
1452  */
1453 HMODULE16 WINAPI GetExePtr( HANDLE16 handle )
1454 {
1455     HTASK16 hTask = 0;
1456     return GetExePtrHelper( handle, &hTask );
1457 }
1458
1459
1460 typedef INT (WINAPI *MessageBoxA_funcptr)(HWND hWnd, LPCSTR text, LPCSTR title, UINT type);
1461
1462 /**************************************************************************
1463  *           FatalAppExit   (KERNEL.137)
1464  */
1465 void WINAPI FatalAppExit16( UINT16 action, LPCSTR str )
1466 {
1467     TDB *pTask = TASK_GetCurrent();
1468
1469     if (!pTask || !(pTask->error_mode & SEM_NOGPFAULTERRORBOX))
1470     {
1471         HMODULE mod = GetModuleHandleA( "user32.dll" );
1472         if (mod)
1473         {
1474             MessageBoxA_funcptr pMessageBoxA = (MessageBoxA_funcptr)GetProcAddress( mod, "MessageBoxA" );
1475             if (pMessageBoxA)
1476             {
1477                 pMessageBoxA( 0, str, NULL, MB_SYSTEMMODAL | MB_OK );
1478                 goto done;
1479             }
1480         }
1481         ERR( "%s\n", debugstr_a(str) );
1482     }
1483  done:
1484     ExitThread(0xff);
1485 }
1486
1487
1488 /***********************************************************************
1489  *           GetAppCompatFlags   (KERNEL.354)
1490  */
1491 DWORD WINAPI GetAppCompatFlags16( HTASK16 hTask )
1492 {
1493     TDB *pTask;
1494
1495     if (!hTask) hTask = GetCurrentTask();
1496     if (!(pTask=TASK_GetPtr( hTask ))) return 0;
1497     if (GlobalSize16(hTask) < sizeof(TDB)) return 0;
1498     return pTask->compat_flags;
1499 }
1500
1501
1502 /***********************************************************************
1503  *           GetDOSEnvironment     (KERNEL.131)
1504  *
1505  * Note: the environment is allocated once, it doesn't track changes
1506  * made using the Win32 API. This shouldn't matter.
1507  *
1508  * Format of a 16-bit environment block:
1509  * ASCIIZ   string 1 (xx=yy format)
1510  * ...
1511  * ASCIIZ   string n
1512  * BYTE     0
1513  * WORD     1
1514  * ASCIIZ   program name (e.g. C:\WINDOWS\SYSTEM\KRNL386.EXE)
1515  */
1516 SEGPTR WINAPI GetDOSEnvironment16(void)
1517 {
1518     static const char ENV_program_name[] = "C:\\WINDOWS\\SYSTEM\\KRNL386.EXE";
1519     static HGLOBAL16 handle;  /* handle to the 16 bit environment */
1520
1521     if (!handle)
1522     {
1523         DWORD size;
1524         LPSTR p, env;
1525
1526         p = env = GetEnvironmentStringsA();
1527         while (*p) p += strlen(p) + 1;
1528         p++;  /* skip last null */
1529         size = (p - env) + sizeof(WORD) + sizeof(ENV_program_name);
1530         handle = GlobalAlloc16( GMEM_FIXED, size );
1531         if (handle)
1532         {
1533             WORD one = 1;
1534             LPSTR env16 = GlobalLock16( handle );
1535             memcpy( env16, env, p - env );
1536             memcpy( env16 + (p - env), &one, sizeof(one));
1537             memcpy( env16 + (p - env) + sizeof(WORD), ENV_program_name, sizeof(ENV_program_name));
1538             GlobalUnlock16( handle );
1539         }
1540         FreeEnvironmentStringsA( env );
1541     }
1542     return WOWGlobalLock16( handle );
1543 }