loader/task.c

   1 /*
   2  * Task functions
   3  *
   4  * Copyright 1995 Alexandre Julliard
   5  */
   6
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <assert.h>
  10 #include <unistd.h>
  11
  12 #include "wine/winbase16.h"
  13 #include "user.h"
  14 #include "callback.h"
  15 #include "drive.h"
  16 #include "file.h"
  17 #include "global.h"
  18 #include "instance.h"
  19 #include "message.h"
  20 #include "miscemu.h"
  21 #include "module.h"
  22 #include "neexe.h"
  23 #include "peexe.h"
  24 #include "pe_image.h"
  25 #include "process.h"
  26 #include "queue.h"
  27 #include "selectors.h"
  28 #include "stackframe.h"
  29 #include "task.h"
  30 #include "thread.h"
  31 #include "toolhelp.h"
  32 #include "winnt.h"
  33 #include "winsock.h"
  34 #include "thread.h"
  35 #include "syslevel.h"
  36 #include "debugtools.h"
  37 #include "dosexe.h"
  38 #include "dde_proc.h"
  39 #include "services.h"
  40 #include "server.h"
  41
  42 DECLARE_DEBUG_CHANNEL(relay)
  43 DECLARE_DEBUG_CHANNEL(task)
  44 DECLARE_DEBUG_CHANNEL(toolhelp)
  45
  46   /* Min. number of thunks allocated when creating a new segment */
  47 #define MIN_THUNKS  32
  48
  49   /* Pointer to function to switch to a larger stack */
  50 int (*IF1632_CallLargeStack)( int (*func)(), void *arg ) = NULL;
  51
  52   /* Pointer to debugger callback routine */
  53 void (*TASK_AddTaskEntryBreakpoint)( HTASK16 hTask ) = NULL;
  54
  55 static THHOOK DefaultThhook = { 0 };
  56 THHOOK *pThhook = &DefaultThhook;
  57
  58 #define hCurrentTask (pThhook->CurTDB)
  59 #define hFirstTask   (pThhook->HeadTDB)
  60 #define hLockedTask  (pThhook->LockTDB)
  61
  62 static HTASK16 hTaskToKill = 0;
  63 static UINT16 nTaskCount = 0;
  64
  65 static HANDLE TASK_ScheduleEvent = INVALID_HANDLE_VALUE;
  66
  67 static void TASK_YieldToSystem( void );
  68
  69
  70 /***********************************************************************
  71  *           TASK_InstallTHHook
  72  */
  73 void TASK_InstallTHHook( THHOOK *pNewThhook )
  74 {
  75      THHOOK *pOldThhook = pThhook;
  76
  77      pThhook = pNewThhook? pNewThhook : &DefaultThhook;
  78
  79      *pThhook = *pOldThhook;
  80 }
  81
  82 /***********************************************************************
  83  *           TASK_GetNextTask
  84  */
  85 HTASK16 TASK_GetNextTask( HTASK16 hTask )
  86 {
  87     TDB* pTask = (TDB*)GlobalLock16(hTask);
  88
  89     if (pTask->hNext) return pTask->hNext;
  90     return (hFirstTask != hTask) ? hFirstTask : 0;
  91 }
  92
  93 /***********************************************************************
  94  *           TASK_LinkTask
  95  */
  96 static void TASK_LinkTask( HTASK16 hTask )
  97 {
  98     HTASK16 *prevTask;
  99     TDB *pTask;
 100
 101     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
 102     prevTask = &hFirstTask;
 103     while (*prevTask)
 104     {
 105         TDB *prevTaskPtr = (TDB *)GlobalLock16( *prevTask );
 106         if (prevTaskPtr->priority >= pTask->priority) break;
 107         prevTask = &prevTaskPtr->hNext;
 108     }
 109     pTask->hNext = *prevTask;
 110     *prevTask = hTask;
 111     nTaskCount++;
 112 }
 113
 114
 115 /***********************************************************************
 116  *           TASK_UnlinkTask
 117  */
 118 static void TASK_UnlinkTask( HTASK16 hTask )
 119 {
 120     HTASK16 *prevTask;
 121     TDB *pTask;
 122
 123     prevTask = &hFirstTask;
 124     while (*prevTask && (*prevTask != hTask))
 125     {
 126         pTask = (TDB *)GlobalLock16( *prevTask );
 127         prevTask = &pTask->hNext;
 128     }
 129     if (*prevTask)
 130     {
 131         pTask = (TDB *)GlobalLock16( *prevTask );
 132         *prevTask = pTask->hNext;
 133         pTask->hNext = 0;
 134         nTaskCount--;
 135     }
 136 }
 137
 138
 139 /***********************************************************************
 140  *           TASK_CreateThunks
 141  *
 142  * Create a thunk free-list in segment 'handle', starting from offset 'offset'
 143  * and containing 'count' entries.
 144  */
 145 static void TASK_CreateThunks( HGLOBAL16 handle, WORD offset, WORD count )
 146 {
 147     int i;
 148     WORD free;
 149     THUNKS *pThunk;
 150
 151     pThunk = (THUNKS *)((BYTE *)GlobalLock16( handle ) + offset);
 152     pThunk->next = 0;
 153     pThunk->magic = THUNK_MAGIC;
 154     pThunk->free = (int)&pThunk->thunks - (int)pThunk;
 155     free = pThunk->free;
 156     for (i = 0; i < count-1; i++)
 157     {
 158         free += 8;  /* Offset of next thunk */
 159         pThunk->thunks[4*i] = free;
 160     }
 161     pThunk->thunks[4*i] = 0;  /* Last thunk */
 162 }
 163
 164
 165 /***********************************************************************
 166  *           TASK_AllocThunk
 167  *
 168  * Allocate a thunk for MakeProcInstance().
 169  */
 170 static SEGPTR TASK_AllocThunk( HTASK16 hTask )
 171 {
 172     TDB *pTask;
 173     THUNKS *pThunk;
 174     WORD sel, base;
 175
 176     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
 177     sel = pTask->hCSAlias;
 178     pThunk = &pTask->thunks;
 179     base = (int)pThunk - (int)pTask;
 180     while (!pThunk->free)
 181     {
 182         sel = pThunk->next;
 183         if (!sel)  /* Allocate a new segment */
 184         {
 185             sel = GLOBAL_Alloc( GMEM_FIXED, sizeof(THUNKS) + (MIN_THUNKS-1)*8,
 186                                 pTask->hPDB, TRUE, FALSE, FALSE );
 187             if (!sel) return (SEGPTR)0;
 188             TASK_CreateThunks( sel, 0, MIN_THUNKS );
 189             pThunk->next = sel;
 190         }
 191         pThunk = (THUNKS *)GlobalLock16( sel );
 192         base = 0;
 193     }
 194     base += pThunk->free;
 195     pThunk->free = *(WORD *)((BYTE *)pThunk + pThunk->free);
 196     return PTR_SEG_OFF_TO_SEGPTR( sel, base );
 197 }
 198
 199
 200 /***********************************************************************
 201  *           TASK_FreeThunk
 202  *
 203  * Free a MakeProcInstance() thunk.
 204  */
 205 static BOOL TASK_FreeThunk( HTASK16 hTask, SEGPTR thunk )
 206 {
 207     TDB *pTask;
 208     THUNKS *pThunk;
 209     WORD sel, base;
 210
 211     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
 212     sel = pTask->hCSAlias;
 213     pThunk = &pTask->thunks;
 214     base = (int)pThunk - (int)pTask;
 215     while (sel && (sel != HIWORD(thunk)))
 216     {
 217         sel = pThunk->next;
 218         pThunk = (THUNKS *)GlobalLock16( sel );
 219         base = 0;
 220     }
 221     if (!sel) return FALSE;
 222     *(WORD *)((BYTE *)pThunk + LOWORD(thunk) - base) = pThunk->free;
 223     pThunk->free = LOWORD(thunk) - base;
 224     return TRUE;
 225 }
 226
 227
 228 /***********************************************************************
 229  *           TASK_CallToStart
 230  *
 231  * 32-bit entry point for a new task. This function is responsible for
 232  * setting up the registers and jumping to the 16-bit entry point.
 233  */
 234 static void TASK_CallToStart(void)
 235 {
 236     TDB *pTask = (TDB *)GlobalLock16( GetCurrentTask() );
 237     NE_MODULE *pModule = NE_GetPtr( pTask->hModule );
 238     SEGTABLEENTRY *pSegTable = NE_SEG_TABLE( pModule );
 239
 240     SYSDEPS_SetCurThread( pTask->thdb );
 241     CLIENT_InitThread();
 242
 243     /* Terminate the stack frame chain */
 244     memset(THREAD_STACK16( pTask->thdb ), '\0', sizeof(STACK16FRAME));
 245
 246     /* Initialize process critical section */
 247     InitializeCriticalSection( &PROCESS_Current()->crit_section );
 248
 249     /* Call USER signal proc */
 250     PROCESS_CallUserSignalProc( USIG_THREAD_INIT, 0 );  /* for initial thread */
 251     PROCESS_CallUserSignalProc( USIG_PROCESS_INIT, 0 );
 252     PROCESS_CallUserSignalProc( USIG_PROCESS_LOADED, 0 );
 253     PROCESS_CallUserSignalProc( USIG_PROCESS_RUNNING, 0 );
 254
 255     if (pModule->flags & NE_FFLAGS_WIN32)
 256     {
 257         ERR_(task)("Called for Win32 task!\n" );
 258         ExitProcess( 1 );
 259     }
 260     else if (pModule->dos_image)
 261     {
 262         DOSVM_Enter( NULL );
 263         ExitProcess( 0 );
 264     }
 265     else
 266     {
 267         /* Registers at initialization must be:
 268          * ax   zero
 269          * bx   stack size in bytes
 270          * cx   heap size in bytes
 271          * si   previous app instance
 272          * di   current app instance
 273          * bp   zero
 274          * es   selector to the PSP
 275          * ds   dgroup of the application
 276          * ss   stack selector
 277          * sp   top of the stack
 278          */
 279         CONTEXT context;
 280
 281         memset( &context, 0, sizeof(context) );
 282         CS_reg(&context)  = GlobalHandleToSel16(pSegTable[pModule->cs - 1].hSeg);
 283         DS_reg(&context)  = GlobalHandleToSel16(pSegTable[pModule->dgroup - 1].hSeg);
 284         ES_reg(&context)  = pTask->hPDB;
 285         EIP_reg(&context) = pModule->ip;
 286         EBX_reg(&context) = pModule->stack_size;
 287         ECX_reg(&context) = pModule->heap_size;
 288         EDI_reg(&context) = context.SegDs;
 289
 290         TRACE_(task)("Starting main program: cs:ip=%04lx:%04x ds=%04lx ss:sp=%04x:%04x\n",
 291                       CS_reg(&context), IP_reg(&context), DS_reg(&context),
 292                       SELECTOROF(pTask->thdb->cur_stack),
 293                       OFFSETOF(pTask->thdb->cur_stack) );
 294
 295         Callbacks->CallRegisterShortProc( &context, 0 );
 296         /* This should never return */
 297         ERR_(task)("Main program returned! (should never happen)\n" );
 298         ExitProcess( 1 );
 299     }
 300 }
 301
 302
 303 /***********************************************************************
 304  *           TASK_Create
 305  *
 306  * NOTE: This routine might be called by a Win32 thread. We don't have
 307  *       any real problems with that, since we operated merely on a private
 308  *       TDB structure that is not yet linked into the task list.
 309  */
 310 BOOL TASK_Create( THDB *thdb, NE_MODULE *pModule, HINSTANCE16 hInstance,
 311                   HINSTANCE16 hPrevInstance, UINT16 cmdShow)
 312 {
 313     HTASK16 hTask;
 314     TDB *pTask;
 315     LPSTR cmd_line;
 316     WORD sp;
 317     char *stack32Top;
 318     char name[10];
 319     STACK16FRAME *frame16;
 320     STACK32FRAME *frame32;
 321     PDB *pdb32 = thdb->process;
 322     SEGTABLEENTRY *pSegTable = NE_SEG_TABLE( pModule );
 323
 324       /* Allocate the task structure */
 325
 326     hTask = GLOBAL_Alloc( GMEM_FIXED | GMEM_ZEROINIT, sizeof(TDB),
 327                           pModule->self, FALSE, FALSE, FALSE );
 328     if (!hTask) return FALSE;
 329     pTask = (TDB *)GlobalLock16( hTask );
 330
 331     /* Fill the task structure */
 332
 333     pTask->nEvents       = 0;
 334     pTask->hSelf         = hTask;
 335     pTask->flags         = 0;
 336
 337     if (pModule->flags & NE_FFLAGS_WIN32)
 338         pTask->flags    |= TDBF_WIN32;
 339     if (pModule->lpDosTask)
 340         pTask->flags    |= TDBF_WINOLDAP;
 341
 342     pTask->version       = pModule->expected_version;
 343     pTask->hInstance     = hInstance? hInstance : pModule->self;
 344     pTask->hPrevInstance = hPrevInstance;
 345     pTask->hModule       = pModule->self;
 346     pTask->hParent       = GetCurrentTask();
 347     pTask->magic         = TDB_MAGIC;
 348     pTask->nCmdShow      = cmdShow;
 349     pTask->thdb          = thdb;
 350     pTask->curdrive      = DRIVE_GetCurrentDrive() | 0x80;
 351     strcpy( pTask->curdir, "\\" );
 352     lstrcpynA( pTask->curdir + 1, DRIVE_GetDosCwd( DRIVE_GetCurrentDrive() ),
 353                  sizeof(pTask->curdir) - 1 );
 354
 355       /* Create the thunks block */
 356
 357     TASK_CreateThunks( hTask, (int)&pTask->thunks - (int)pTask, 7 );
 358
 359       /* Copy the module name */
 360
 361     GetModuleName16( pModule->self, name, sizeof(name) );
 362     strncpy( pTask->module_name, name, sizeof(pTask->module_name) );
 363
 364       /* Allocate a selector for the PDB */
 365
 366     pTask->hPDB = GLOBAL_CreateBlock( GMEM_FIXED, &pTask->pdb, sizeof(PDB16),
 367                                     pModule->self, FALSE, FALSE, FALSE, NULL );
 368
 369       /* Fill the PDB */
 370
 371     pTask->pdb.int20 = 0x20cd;
 372     pTask->pdb.dispatcher[0] = 0x9a;  /* ljmp */
 373     PUT_DWORD(&pTask->pdb.dispatcher[1], (DWORD)NE_GetEntryPoint(
 374            GetModuleHandle16("KERNEL"), 102 ));  /* KERNEL.102 is DOS3Call() */
 375     pTask->pdb.savedint22 = INT_GetPMHandler( 0x22 );
 376     pTask->pdb.savedint23 = INT_GetPMHandler( 0x23 );
 377     pTask->pdb.savedint24 = INT_GetPMHandler( 0x24 );
 378     pTask->pdb.fileHandlesPtr =
 379         PTR_SEG_OFF_TO_SEGPTR( GlobalHandleToSel16(pTask->hPDB),
 380                                (int)&((PDB16 *)0)->fileHandles );
 381     pTask->pdb.hFileHandles = 0;
 382     memset( pTask->pdb.fileHandles, 0xff, sizeof(pTask->pdb.fileHandles) );
 383     pTask->pdb.environment    = pdb32->env_db->env_sel;
 384     pTask->pdb.nbFiles        = 20;
 385
 386     /* Fill the command line */
 387
 388     cmd_line = pdb32->env_db->cmd_line;
 389     while (*cmd_line && (*cmd_line != ' ') && (*cmd_line != '\t')) cmd_line++;
 390     while ((*cmd_line == ' ') || (*cmd_line == '\t')) cmd_line++;
 391     lstrcpynA( pTask->pdb.cmdLine+1, cmd_line, sizeof(pTask->pdb.cmdLine)-1);
 392     pTask->pdb.cmdLine[0] = strlen( pTask->pdb.cmdLine + 1 );
 393
 394       /* Get the compatibility flags */
 395
 396     pTask->compat_flags = GetProfileIntA( "Compatibility", name, 0 );
 397
 398       /* Allocate a code segment alias for the TDB */
 399
 400     pTask->hCSAlias = GLOBAL_CreateBlock( GMEM_FIXED, (void *)pTask,
 401                                           sizeof(TDB), pTask->hPDB, TRUE,
 402                                           FALSE, FALSE, NULL );
 403
 404       /* Set the owner of the environment block */
 405
 406     FarSetOwner16( pTask->pdb.environment, pTask->hPDB );
 407
 408       /* Default DTA overwrites command-line */
 409
 410     pTask->dta = PTR_SEG_OFF_TO_SEGPTR( pTask->hPDB,
 411                                 (int)&pTask->pdb.cmdLine - (int)&pTask->pdb );
 412
 413     /* Enter task handle into thread and process */
 414
 415     pTask->thdb->teb.htask16 = pTask->thdb->process->task = hTask;
 416      TRACE_(task)("module='%s' cmdline='%s' task=%04x\n", name, cmd_line, hTask );
 417
 418     if (pTask->flags & TDBF_WIN32) return TRUE;
 419
 420     /* If we have a DGROUP/hInstance, use it for 16-bit stack */
 421
 422     if ( hInstance )
 423     {
 424         if (!(sp = pModule->sp))
 425             sp = pSegTable[pModule->ss-1].minsize + pModule->stack_size;
 426         sp &= ~1;  sp -= sizeof(STACK16FRAME);
 427         pTask->thdb->cur_stack = PTR_SEG_OFF_TO_SEGPTR( hInstance, sp );
 428     }
 429
 430     /* Create the 16-bit stack frame */
 431
 432     pTask->thdb->cur_stack -= sizeof(STACK16FRAME);
 433     frame16 = (STACK16FRAME *)PTR_SEG_TO_LIN( pTask->thdb->cur_stack );
 434     frame16->ebp = OFFSETOF( pTask->thdb->cur_stack ) + (int)&((STACK16FRAME *)0)->bp;
 435     frame16->bp = LOWORD(frame16->ebp);
 436     frame16->ds = frame16->es = hInstance;
 437     frame16->fs = 0;
 438     frame16->entry_point = 0;
 439     frame16->entry_cs = 0;
 440     frame16->mutex_count = 1; /* TASK_Reschedule is called from 16-bit code */
 441     /* The remaining fields will be initialized in TASK_Reschedule */
 442
 443     /* Create the 32-bit stack frame */
 444
 445     stack32Top = (char*)pTask->thdb->teb.stack_top;
 446     frame16->frame32 = frame32 = (STACK32FRAME *)stack32Top - 1;
 447     frame32->frame16 = pTask->thdb->cur_stack + sizeof(STACK16FRAME);
 448     frame32->edi     = 0;
 449     frame32->esi     = 0;
 450     frame32->edx     = 0;
 451     frame32->ecx     = 0;
 452     frame32->ebx     = 0;
 453     frame32->retaddr = (DWORD)TASK_CallToStart;
 454     /* The remaining fields will be initialized in TASK_Reschedule */
 455
 456     return TRUE;
 457 }
 458
 459 /***********************************************************************
 460  *           TASK_StartTask
 461  *
 462  * NOTE: This routine might be called by a Win32 thread. Thus, we need
 463  *       to be careful to protect global data structures. We do this
 464  *       by entering the Win16Lock while linking the task into the
 465  *       global task list.
 466  */
 467 void TASK_StartTask( HTASK16 hTask )
 468 {
 469     TDB *pTask = (TDB *)GlobalLock16( hTask );
 470     if ( !pTask ) return;
 471
 472     /* Add the task to the linked list */
 473
 474     SYSLEVEL_EnterWin16Lock();
 475     TASK_LinkTask( hTask );
 476     SYSLEVEL_LeaveWin16Lock();
 477
 478     TRACE_(task)("linked task %04x\n", hTask );
 479
 480     /* If requested, add entry point breakpoint */
 481
 482     if ( TASK_AddTaskEntryBreakpoint )
 483         TASK_AddTaskEntryBreakpoint( hTask );
 484
 485     /* Get the task up and running. */
 486
 487     if ( THREAD_IsWin16( pTask->thdb ) )
 488     {
 489         /* Post event to start the task */
 490         PostEvent16( hTask );
 491
 492         /* If we ourselves are a 16-bit task, we Yield() directly. */
 493         if ( THREAD_IsWin16( THREAD_Current() ) )
 494             OldYield16();
 495     }
 496 }
 497
 498
 499 /***********************************************************************
 500  *           TASK_DeleteTask
 501  */
 502 static void TASK_DeleteTask( HTASK16 hTask )
 503 {
 504     TDB *pTask;
 505     HGLOBAL16 hPDB;
 506
 507     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
 508     hPDB = pTask->hPDB;
 509
 510     pTask->magic = 0xdead; /* invalidate signature */
 511
 512     /* Delete the Win32 part of the task */
 513
 514 /*    PROCESS_FreePDB( pTask->thdb->process ); FIXME */
 515 /*    K32OBJ_DecCount( &pTask->thdb->header ); FIXME */
 516
 517     /* Free the selector aliases */
 518
 519     GLOBAL_FreeBlock( pTask->hCSAlias );
 520     GLOBAL_FreeBlock( pTask->hPDB );
 521
 522     /* Free the task module */
 523
 524     FreeModule16( pTask->hModule );
 525
 526     /* Free the task structure itself */
 527
 528     GlobalFree16( hTask );
 529
 530     /* Free all memory used by this task (including the 32-bit stack, */
 531     /* the environment block and the thunk segments). */
 532
 533     GlobalFreeAll16( hPDB );
 534 }
 535
 536 /***********************************************************************
 537  *           TASK_KillTask
 538  */
 539 void TASK_KillTask( HTASK16 hTask )
 540 {
 541     TDB *pTask;
 542
 543     /* Enter the Win16Lock to protect global data structures */
 544     SYSLEVEL_EnterWin16Lock();
 545
 546     if ( !hTask ) hTask = GetCurrentTask();
 547     pTask = (TDB *)GlobalLock16( hTask );
 548     if ( !pTask )
 549     {
 550         SYSLEVEL_LeaveWin16Lock();
 551         return;
 552     }
 553
 554     TRACE_(task)("Killing task %04x\n", hTask );
 555
 556     /* Delete active sockets */
 557
 558     if( pTask->pwsi )
 559         WINSOCK_DeleteTaskWSI( pTask, pTask->pwsi );
 560
 561 #ifdef MZ_SUPPORTED
 562 {
 563     /* Kill DOS VM task */
 564     NE_MODULE *pModule = NE_GetPtr( pTask->hModule );
 565     if ( pModule->lpDosTask )
 566         MZ_KillModule( pModule->lpDosTask );
 567 }
 568 #endif
 569
 570     /* Perform USER cleanup */
 571
 572     if (pTask->userhandler)
 573         pTask->userhandler( hTask, USIG16_TERMINATION, 0,
 574                             pTask->hInstance, pTask->hQueue );
 575
 576     PROCESS_CallUserSignalProc( USIG_PROCESS_EXIT, 0 );
 577     PROCESS_CallUserSignalProc( USIG_THREAD_EXIT, 0 );     /* FIXME */
 578     PROCESS_CallUserSignalProc( USIG_PROCESS_DESTROY, 0 );
 579
 580     if (nTaskCount <= 1)
 581     {
 582         TRACE_(task)("this is the last task, exiting\n" );
 583         ExitKernel16();
 584     }
 585
 586     /* FIXME: Hack! Send a message to the initial task so that
 587      * the GetMessage wakes up and the initial task can check whether
 588      * it is the only remaining one and terminate itself ...
 589      * The initial task should probably install hooks or something
 590      * to get informed about task termination :-/
 591      */
 592     Callout.PostAppMessage16( PROCESS_Initial()->task, WM_NULL, 0, 0 );
 593
 594     /* Remove the task from the list to be sure we never switch back to it */
 595     TASK_UnlinkTask( hTask );
 596     if( nTaskCount )
 597     {
 598         TDB* p = (TDB *)GlobalLock16( hFirstTask );
 599         while( p )
 600         {
 601             if( p->hYieldTo == hTask ) p->hYieldTo = 0;
 602             p = (TDB *)GlobalLock16( p->hNext );
 603         }
 604     }
 605
 606     pTask->nEvents = 0;
 607
 608     if ( hLockedTask == hTask )
 609         hLockedTask = 0;
 610
 611     if ( hTaskToKill && ( hTaskToKill != hCurrentTask ) )
 612     {
 613         /* If another task is already marked for destruction, */
 614         /* we can kill it now, as we are in another context.  */
 615         TASK_DeleteTask( hTaskToKill );
 616         hTaskToKill = 0;
 617     }
 618
 619     /*
 620      * If hTask is not the task currently scheduled by the Win16
 621      * scheduler, we simply delete it; otherwise we mark it for
 622      * destruction.  Note that if the current task is a 32-bit
 623      * one, hCurrentTask is *different* from GetCurrentTask()!
 624      */
 625     if ( hTask == hCurrentTask )
 626     {
 627         assert( hTaskToKill == 0 || hTaskToKill == hCurrentTask );
 628         hTaskToKill = hCurrentTask;
 629     }
 630     else
 631         TASK_DeleteTask( hTask );
 632
 633     SYSLEVEL_LeaveWin16Lock();
 634 }
 635
 636
 637 /***********************************************************************
 638  *           TASK_KillCurrentTask
 639  *
 640  * Kill the currently running task. As it's not possible to kill the
 641  * current task like this, it is simply marked for destruction, and will
 642  * be killed when either TASK_Reschedule or this function is called again
 643  * in the context of another task.
 644  */
 645 void TASK_KillCurrentTask( INT16 exitCode )
 646 {
 647     if ( !THREAD_IsWin16( THREAD_Current() ) )
 648     {
 649         FIXME_(task)("called for Win32 thread (%04x)!\n", THREAD_Current()->teb_sel);
 650         return;
 651     }
 652
 653     assert(hCurrentTask == GetCurrentTask());
 654
 655     TRACE_(task)("Killing current task %04x\n", hCurrentTask );
 656
 657     TASK_KillTask( 0 );
 658
 659     TASK_YieldToSystem();
 660
 661     /* We should never return from this Yield() */
 662
 663     ERR_(task)("Return of the living dead %04x!!!\n", hCurrentTask);
 664     exit(1);
 665 }
 666
 667 /***********************************************************************
 668  *           TASK_Reschedule
 669  *
 670  * This is where all the magic of task-switching happens!
 671  *
 672  * Note: This function should only be called via the TASK_YieldToSystem()
 673  *       wrapper, to make sure that all the context is saved correctly.
 674  *
 675  *       It must not call functions that may yield control.
 676  */
 677 BOOL TASK_Reschedule(void)
 678 {
 679     TDB *pOldTask = NULL, *pNewTask;
 680     HTASK16 hTask = 0;
 681     STACK16FRAME *newframe16;
 682
 683     /* Create scheduler event */
 684     if ( TASK_ScheduleEvent == INVALID_HANDLE_VALUE )
 685     {
 686         TASK_ScheduleEvent = CreateEventA( NULL, TRUE, FALSE, NULL );
 687         TASK_ScheduleEvent = ConvertToGlobalHandle( TASK_ScheduleEvent );
 688     }
 689
 690     /* Get the initial task up and running */
 691     if (!hCurrentTask && GetCurrentTask())
 692     {
 693         /* We need to remove one pair of stackframes (exept for Winelib) */
 694         STACK16FRAME *oldframe16 = CURRENT_STACK16;
 695         STACK32FRAME *oldframe32 = oldframe16? oldframe16->frame32 : NULL;
 696         STACK16FRAME *newframe16 = oldframe32? PTR_SEG_TO_LIN( oldframe32->frame16 ) : NULL;
 697         STACK32FRAME *newframe32 = newframe16? newframe16->frame32 : NULL;
 698         if (newframe32)
 699         {
 700             newframe16->entry_ip     = oldframe16->entry_ip;
 701             newframe16->entry_cs     = oldframe16->entry_cs;
 702             newframe16->ip           = oldframe16->ip;
 703             newframe16->cs           = oldframe16->cs;
 704             newframe32->ebp          = oldframe32->ebp;
 705             newframe32->restore_addr = oldframe32->restore_addr;
 706             newframe32->codeselector = oldframe32->codeselector;
 707
 708             THREAD_Current()->cur_stack = oldframe32->frame16;
 709         }
 710
 711         hCurrentTask = GetCurrentTask();
 712         pNewTask = (TDB *)GlobalLock16( hCurrentTask );
 713         pNewTask->ss_sp = pNewTask->thdb->cur_stack;
 714         return FALSE;
 715     }
 716
 717     /* NOTE: As we are entered from 16-bit code, we hold the Win16Lock.
 718              We hang onto it thoughout most of this routine, so that accesses
 719              to global variables (most notably the task list) are protected. */
 720     assert(hCurrentTask == GetCurrentTask());
 721
 722     TRACE_(task)("entered with hTask %04x (pid %d)\n", hCurrentTask, getpid());
 723
 724 #ifdef CONFIG_IPC
 725     /* FIXME: What about the Win16Lock ??? */
 726     dde_reschedule();
 727 #endif
 728       /* First check if there's a task to kill */
 729
 730     if (hTaskToKill && (hTaskToKill != hCurrentTask))
 731     {
 732         TASK_DeleteTask( hTaskToKill );
 733         hTaskToKill = 0;
 734     }
 735
 736     /* Find a task to yield to */
 737
 738     pOldTask = (TDB *)GlobalLock16( hCurrentTask );
 739     if (pOldTask && pOldTask->hYieldTo)
 740     {
 741         /* check for DirectedYield() */
 742
 743         hTask = pOldTask->hYieldTo;
 744         pNewTask = (TDB *)GlobalLock16( hTask );
 745         if( !pNewTask || !pNewTask->nEvents) hTask = 0;
 746         pOldTask->hYieldTo = 0;
 747     }
 748
 749     while (!hTask)
 750     {
 751         /* Find a task that has an event pending */
 752
 753         hTask = hFirstTask;
 754         while (hTask)
 755         {
 756             pNewTask = (TDB *)GlobalLock16( hTask );
 757
 758             TRACE_(task)("\ttask = %04x, events = %i\n", hTask, pNewTask->nEvents);
 759
 760             if (pNewTask->nEvents) break;
 761             hTask = pNewTask->hNext;
 762         }
 763         if (hLockedTask && (hTask != hLockedTask)) hTask = 0;
 764         if (hTask) break;
 765
 766         /* No task found, wait for some events to come in */
 767
 768         /* NOTE: We release the Win16Lock while waiting for events. This is to enable
 769                  Win32 threads to thunk down to 16-bit temporarily. Since Win16
 770                  tasks won't execute and Win32 threads are not allowed to enter
 771                  TASK_Reschedule anyway, there should be no re-entrancy problem ... */
 772
 773         ResetEvent( TASK_ScheduleEvent );
 774         SYSLEVEL_ReleaseWin16Lock();
 775         WaitForSingleObject( TASK_ScheduleEvent, INFINITE );
 776         SYSLEVEL_RestoreWin16Lock();
 777     }
 778
 779     if (hTask == hCurrentTask)
 780     {
 781         /* Allow Win32 threads to thunk down even while a Win16 task is
 782            in a tight PeekMessage() or Yield() loop ... */
 783         SYSLEVEL_ReleaseWin16Lock();
 784         SYSLEVEL_RestoreWin16Lock();
 785
 786         TRACE_(task)("returning to the current task(%04x)\n", hTask );
 787         return FALSE;  /* Nothing to do */
 788     }
 789     pNewTask = (TDB *)GlobalLock16( hTask );
 790     TRACE_(task)("Switching to task %04x (%.8s)\n",
 791                   hTask, pNewTask->module_name );
 792
 793      /* Make the task the last in the linked list (round-robin scheduling) */
 794
 795     pNewTask->priority++;
 796     TASK_UnlinkTask( hTask );
 797     TASK_LinkTask( hTask );
 798     pNewTask->priority--;
 799
 800     /* Finish initializing the new task stack if necessary */
 801
 802     newframe16 = THREAD_STACK16( pNewTask->thdb );
 803     if (!newframe16->entry_cs)
 804     {
 805         STACK16FRAME *oldframe16 = CURRENT_STACK16;
 806         STACK32FRAME *oldframe32 = oldframe16->frame32;
 807         STACK32FRAME *newframe32 = newframe16->frame32;
 808         newframe16->entry_ip     = oldframe16->entry_ip;
 809         newframe16->entry_cs     = oldframe16->entry_cs;
 810         newframe16->ip           = oldframe16->ip;
 811         newframe16->cs           = oldframe16->cs;
 812         newframe32->ebp          = oldframe32->ebp;
 813         newframe32->restore_addr = oldframe32->restore_addr;
 814         newframe32->codeselector = oldframe32->codeselector;
 815     }
 816
 817     /* Switch to the new stack */
 818
 819     /* NOTE: We need to release/restore the Win16Lock, as the task
 820              switched to might be at another recursion level than
 821              the old task ... */
 822
 823     SYSLEVEL_ReleaseWin16Lock();
 824
 825     hCurrentTask = hTask;
 826     SYSDEPS_SetCurThread( pNewTask->thdb );
 827     pNewTask->ss_sp = pNewTask->thdb->cur_stack;
 828
 829     SYSLEVEL_RestoreWin16Lock();
 830
 831     return FALSE;
 832 }
 833
 834
 835 /***********************************************************************
 836  *           TASK_YieldToSystem
 837  *
 838  * Scheduler interface, this way we ensure that all "unsafe" events are
 839  * processed outside the scheduler.
 840  */
 841 static void TASK_YieldToSystem( void )
 842 {
 843     if ( !THREAD_IsWin16( THREAD_Current() ) )
 844     {
 845         FIXME_(task)("called for Win32 thread (%04x)!\n", THREAD_Current()->teb_sel);
 846         return;
 847     }
 848
 849     EVENT_Synchronize( FALSE );
 850
 851     Callbacks->CallTaskRescheduleProc();
 852 }
 853
 854
 855 /***********************************************************************
 856  *           InitTask  (KERNEL.91)
 857  *
 858  * Called by the application startup code.
 859  */
 860 void WINAPI InitTask16( CONTEXT *context )
 861 {
 862     TDB *pTask;
 863     NE_MODULE *pModule;
 864     SEGTABLEENTRY *pSegTable;
 865     INSTANCEDATA *pinstance;
 866     LONG stacklow, stackhi;
 867
 868     if (context) EAX_reg(context) = 0;
 869     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
 870     if (!(pModule = NE_GetPtr( pTask->hModule ))) return;
 871
 872     /* Initialize implicitly loaded DLLs */
 873     NE_InitializeDLLs( pTask->hModule );
 874
 875     if (context)
 876     {
 877         /* Registers on return are:
 878          * ax     1 if OK, 0 on error
 879          * cx     stack limit in bytes
 880          * dx     cmdShow parameter
 881          * si     instance handle of the previous instance
 882          * di     instance handle of the new task
 883          * es:bx  pointer to command-line inside PSP
 884          *
 885          * 0 (=%bp) is pushed on the stack
 886          */
 887         SEGPTR ptr = STACK16_PUSH( pTask->thdb, sizeof(WORD) );
 888         *(WORD *)PTR_SEG_TO_LIN(ptr) = 0;
 889         SP_reg(context) -= 2;
 890
 891         EAX_reg(context) = 1;
 892
 893         if (!pTask->pdb.cmdLine[0]) EBX_reg(context) = 0x80;
 894         else
 895         {
 896             LPBYTE p = &pTask->pdb.cmdLine[1];
 897             while ((*p == ' ') || (*p == '\t')) p++;
 898             EBX_reg(context) = 0x80 + (p - pTask->pdb.cmdLine);
 899         }
 900         ECX_reg(context) = pModule->stack_size;
 901         EDX_reg(context) = pTask->nCmdShow;
 902         ESI_reg(context) = (DWORD)pTask->hPrevInstance;
 903         EDI_reg(context) = (DWORD)pTask->hInstance;
 904         ES_reg (context) = (WORD)pTask->hPDB;
 905     }
 906
 907     /* Initialize the local heap */
 908     if ( pModule->heap_size )
 909     {
 910         LocalInit16( pTask->hInstance, 0, pModule->heap_size );
 911     }
 912
 913     /* Initialize the INSTANCEDATA structure */
 914     pSegTable = NE_SEG_TABLE( pModule );
 915     stacklow = pSegTable[pModule->ss - 1].minsize;
 916     stackhi  = stacklow + pModule->stack_size;
 917     if (stackhi > 0xffff) stackhi = 0xffff;
 918     pinstance = (INSTANCEDATA *)PTR_SEG_OFF_TO_LIN(CURRENT_DS, 0);
 919     pinstance->stackbottom = stackhi; /* yup, that's right. Confused me too. */
 920     pinstance->stacktop    = stacklow;
 921     pinstance->stackmin    = OFFSETOF( pTask->thdb->cur_stack );
 922 }
 923
 924
 925 /***********************************************************************
 926  *           WaitEvent  (KERNEL.30)
 927  */
 928 BOOL16 WINAPI WaitEvent16( HTASK16 hTask )
 929 {
 930     TDB *pTask;
 931
 932     if (!hTask) hTask = GetCurrentTask();
 933     pTask = (TDB *)GlobalLock16( hTask );
 934
 935     if ( !THREAD_IsWin16( THREAD_Current() ) )
 936     {
 937         FIXME_(task)("called for Win32 thread (%04x)!\n", THREAD_Current()->teb_sel);
 938         return TRUE;
 939     }
 940
 941     if (pTask->nEvents > 0)
 942     {
 943         pTask->nEvents--;
 944         return FALSE;
 945     }
 946     TASK_YieldToSystem();
 947
 948     /* When we get back here, we have an event */
 949
 950     if (pTask->nEvents > 0) pTask->nEvents--;
 951     return TRUE;
 952 }
 953
 954
 955 /***********************************************************************
 956  *           PostEvent  (KERNEL.31)
 957  */
 958 void WINAPI PostEvent16( HTASK16 hTask )
 959 {
 960     TDB *pTask;
 961
 962     if (!hTask) hTask = GetCurrentTask();
 963     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
 964
 965     if ( !THREAD_IsWin16( pTask->thdb ) )
 966     {
 967         FIXME_(task)("called for Win32 thread (%04x)!\n", pTask->thdb->teb_sel );
 968         return;
 969     }
 970
 971     pTask->nEvents++;
 972     SetEvent( TASK_ScheduleEvent );
 973 }
 974
 975
 976 /***********************************************************************
 977  *           SetPriority  (KERNEL.32)
 978  */
 979 void WINAPI SetPriority16( HTASK16 hTask, INT16 delta )
 980 {
 981     TDB *pTask;
 982     INT16 newpriority;
 983
 984     if (!hTask) hTask = GetCurrentTask();
 985     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
 986     newpriority = pTask->priority + delta;
 987     if (newpriority < -32) newpriority = -32;
 988     else if (newpriority > 15) newpriority = 15;
 989
 990     pTask->priority = newpriority + 1;
 991     TASK_UnlinkTask( hTask );
 992     TASK_LinkTask( hTask );
 993     pTask->priority--;
 994 }
 995
 996
 997 /***********************************************************************
 998  *           LockCurrentTask  (KERNEL.33)
 999  */
1000 HTASK16 WINAPI LockCurrentTask16( BOOL16 bLock )
1001 {
1002     if (bLock) hLockedTask = GetCurrentTask();
1003     else hLockedTask = 0;
1004     return hLockedTask;
1005 }
1006
1007
1008 /***********************************************************************
1009  *           IsTaskLocked  (KERNEL.122)
1010  */
1011 HTASK16 WINAPI IsTaskLocked16(void)
1012 {
1013     return hLockedTask;
1014 }
1015
1016
1017 /***********************************************************************
1018  *           OldYield  (KERNEL.117)
1019  */
1020 void WINAPI OldYield16(void)
1021 {
1022     TDB *pCurTask = (TDB *)GlobalLock16( GetCurrentTask() );
1023
1024     if ( !THREAD_IsWin16( THREAD_Current() ) )
1025     {
1026         FIXME_(task)("called for Win32 thread (%04x)!\n", THREAD_Current()->teb_sel);
1027         return;
1028     }
1029
1030     if (pCurTask) pCurTask->nEvents++;  /* Make sure we get back here */
1031     TASK_YieldToSystem();
1032     if (pCurTask) pCurTask->nEvents--;
1033 }
1034
1035
1036 /***********************************************************************
1037  *           DirectedYield  (KERNEL.150)
1038  */
1039 void WINAPI DirectedYield16( HTASK16 hTask )
1040 {
1041     TDB *pCurTask = (TDB *)GlobalLock16( GetCurrentTask() );
1042
1043     if ( !THREAD_IsWin16( THREAD_Current() ) )
1044     {
1045         FIXME_(task)("called for Win32 thread (%04x)!\n", THREAD_Current()->teb_sel);
1046         return;
1047     }
1048
1049     TRACE_(task)("%04x: DirectedYield(%04x)\n", pCurTask->hSelf, hTask );
1050
1051     pCurTask->hYieldTo = hTask;
1052     OldYield16();
1053
1054     TRACE_(task)("%04x: back from DirectedYield(%04x)\n", pCurTask->hSelf, hTask );
1055 }
1056
1057 /***********************************************************************
1058  *           Yield16  (KERNEL.29)
1059  */
1060 void WINAPI Yield16(void)
1061 {
1062     TDB *pCurTask = (TDB *)GlobalLock16( GetCurrentTask() );
1063
1064     if (pCurTask) pCurTask->hYieldTo = 0;
1065     if (pCurTask && pCurTask->hQueue) Callout.UserYield16();
1066     else OldYield16();
1067 }
1068
1069 /***********************************************************************
1070  *           KERNEL_490  (KERNEL.490)
1071  */
1072 HTASK16 WINAPI KERNEL_490( HTASK16 someTask )
1073 {
1074     if ( !someTask ) return 0;
1075
1076     FIXME_(task)("(%04x): stub\n", someTask );
1077     return 0;
1078 }
1079
1080 /***********************************************************************
1081  *           MakeProcInstance16  (KERNEL.51)
1082  */
1083 FARPROC16 WINAPI MakeProcInstance16( FARPROC16 func, HANDLE16 hInstance )
1084 {
1085     BYTE *thunk,*lfunc;
1086     SEGPTR thunkaddr;
1087
1088     if (!func) {
1089       ERR_(task)("Ouch ! MakeProcInstance called with func == NULL !\n");
1090       return (FARPROC16)0; /* Windows seems to do the same */
1091     }
1092     if (!hInstance) hInstance = CURRENT_DS;
1093     thunkaddr = TASK_AllocThunk( GetCurrentTask() );
1094     if (!thunkaddr) return (FARPROC16)0;
1095     thunk = PTR_SEG_TO_LIN( thunkaddr );
1096     lfunc = PTR_SEG_TO_LIN( func );
1097
1098     TRACE_(task)("(%08lx,%04x): got thunk %08lx\n",
1099                   (DWORD)func, hInstance, (DWORD)thunkaddr );
1100     if (((lfunc[0]==0x8c) && (lfunc[1]==0xd8)) ||
1101         ((lfunc[0]==0x1e) && (lfunc[1]==0x58))
1102     ) {
1103         FIXME_(task)("thunk would be useless for %p, overwriting with nop;nop;\n", func );
1104         lfunc[0]=0x90; /* nop */
1105         lfunc[1]=0x90; /* nop */
1106     }
1107
1108     *thunk++ = 0xb8;    /* movw instance, %ax */
1109     *thunk++ = (BYTE)(hInstance & 0xff);
1110     *thunk++ = (BYTE)(hInstance >> 8);
1111     *thunk++ = 0xea;    /* ljmp func */
1112     *(DWORD *)thunk = (DWORD)func;
1113     return (FARPROC16)thunkaddr;
1114 }
1115
1116
1117 /***********************************************************************
1118  *           FreeProcInstance16  (KERNEL.52)
1119  */
1120 void WINAPI FreeProcInstance16( FARPROC16 func )
1121 {
1122     TRACE_(task)("(%08lx)\n", (DWORD)func );
1123     TASK_FreeThunk( GetCurrentTask(), (SEGPTR)func );
1124 }
1125
1126
1127 /**********************************************************************
1128  *          GetCodeHandle    (KERNEL.93)
1129  */
1130 HANDLE16 WINAPI GetCodeHandle16( FARPROC16 proc )
1131 {
1132     HANDLE16 handle;
1133     BYTE *thunk = (BYTE *)PTR_SEG_TO_LIN( proc );
1134
1135     /* Return the code segment containing 'proc'. */
1136     /* Not sure if this is really correct (shouldn't matter that much). */
1137
1138     /* Check if it is really a thunk */
1139     if ((thunk[0] == 0xb8) && (thunk[3] == 0xea))
1140         handle = GlobalHandle16( thunk[6] + (thunk[7] << 8) );
1141     else
1142         handle = GlobalHandle16( HIWORD(proc) );
1143
1144     return handle;
1145 }
1146
1147 /**********************************************************************
1148  *          GetCodeInfo    (KERNEL.104)
1149  */
1150 VOID WINAPI GetCodeInfo16( FARPROC16 proc, SEGINFO *segInfo )
1151 {
1152     BYTE *thunk = (BYTE *)PTR_SEG_TO_LIN( proc );
1153     NE_MODULE *pModule = NULL;
1154     SEGTABLEENTRY *pSeg = NULL;
1155     WORD segNr;
1156
1157     /* proc is either a thunk, or else a pair of module handle
1158        and segment number. In the first case, we also need to
1159        extract module and segment number. */
1160
1161     if ((thunk[0] == 0xb8) && (thunk[3] == 0xea))
1162     {
1163         WORD selector = thunk[6] + (thunk[7] << 8);
1164         pModule = NE_GetPtr( GlobalHandle16( selector ) );
1165         pSeg = pModule? NE_SEG_TABLE( pModule ) : NULL;
1166
1167         if ( pModule )
1168             for ( segNr = 0; segNr < pModule->seg_count; segNr++, pSeg++ )
1169                 if ( GlobalHandleToSel16(pSeg->hSeg) == selector )
1170                     break;
1171
1172         if ( pModule && segNr >= pModule->seg_count )
1173             pSeg = NULL;
1174     }
1175     else
1176     {
1177         pModule = NE_GetPtr( HIWORD( proc ) );
1178         segNr   = LOWORD( proc );
1179
1180         if ( pModule && segNr < pModule->seg_count )
1181             pSeg = NE_SEG_TABLE( pModule ) + segNr;
1182     }
1183
1184     /* fill in segment information */
1185
1186     segInfo->offSegment = pSeg? pSeg->filepos : 0;
1187     segInfo->cbSegment  = pSeg? pSeg->size : 0;
1188     segInfo->flags      = pSeg? pSeg->flags : 0;
1189     segInfo->cbAlloc    = pSeg? pSeg->minsize : 0;
1190     segInfo->h          = pSeg? pSeg->hSeg : 0;
1191     segInfo->alignShift = pModule? pModule->alignment : 0;
1192 }
1193
1194
1195 /**********************************************************************
1196  *          DefineHandleTable16    (KERNEL.94)
1197  */
1198 BOOL16 WINAPI DefineHandleTable16( WORD wOffset )
1199 {
1200     return TRUE;  /* FIXME */
1201 }
1202
1203
1204 /***********************************************************************
1205  *           SetTaskQueue  (KERNEL.34)
1206  */
1207 HQUEUE16 WINAPI SetTaskQueue16( HTASK16 hTask, HQUEUE16 hQueue )
1208 {
1209     HQUEUE16 hPrev;
1210     TDB *pTask;
1211
1212     if (!hTask) hTask = GetCurrentTask();
1213     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
1214
1215     hPrev = pTask->hQueue;
1216     pTask->hQueue = hQueue;
1217
1218     return hPrev;
1219 }
1220
1221
1222 /***********************************************************************
1223  *           GetTaskQueue  (KERNEL.35)
1224  */
1225 HQUEUE16 WINAPI GetTaskQueue16( HTASK16 hTask )
1226 {
1227     TDB *pTask;
1228
1229     if (!hTask) hTask = GetCurrentTask();
1230     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
1231     return pTask->hQueue;
1232 }
1233
1234 /***********************************************************************
1235  *           SetThreadQueue  (KERNEL.463)
1236  */
1237 HQUEUE16 WINAPI SetThreadQueue16( DWORD thread, HQUEUE16 hQueue )
1238 {
1239     THDB *thdb = thread? THREAD_IdToTHDB( thread ) : THREAD_Current();
1240     HQUEUE16 oldQueue = thdb? thdb->teb.queue : 0;
1241
1242     if ( thdb )
1243     {
1244         thdb->teb.queue = hQueue;
1245
1246         if ( GetTaskQueue16( thdb->process->task ) == oldQueue )
1247             SetTaskQueue16( thdb->process->task, hQueue );
1248     }
1249
1250     return oldQueue;
1251 }
1252
1253 /***********************************************************************
1254  *           GetThreadQueue  (KERNEL.464)
1255  */
1256 HQUEUE16 WINAPI GetThreadQueue16( DWORD thread )
1257 {
1258     THDB *thdb = NULL;
1259     if ( !thread )
1260         thdb = THREAD_Current();
1261     else if ( HIWORD(thread) )
1262         thdb = THREAD_IdToTHDB( thread );
1263     else if ( IsTask16( (HTASK16)thread ) )
1264         thdb = ((TDB *)GlobalLock16( (HANDLE16)thread ))->thdb;
1265
1266     return (HQUEUE16)(thdb? thdb->teb.queue : 0);
1267 }
1268
1269 /***********************************************************************
1270  *           SetFastQueue  (KERNEL.624)
1271  */
1272 VOID WINAPI SetFastQueue16( DWORD thread, HANDLE hQueue )
1273 {
1274     THDB *thdb = NULL;
1275     if ( !thread )
1276         thdb = THREAD_Current();
1277     else if ( HIWORD(thread) )
1278         thdb = THREAD_IdToTHDB( thread );
1279     else if ( IsTask16( (HTASK16)thread ) )
1280         thdb = ((TDB *)GlobalLock16( (HANDLE16)thread ))->thdb;
1281
1282     if ( thdb ) thdb->teb.queue = (HQUEUE16) hQueue;
1283 }
1284
1285 /***********************************************************************
1286  *           GetFastQueue  (KERNEL.625)
1287  */
1288 HANDLE WINAPI GetFastQueue16( void )
1289 {
1290     THDB *thdb = THREAD_Current();
1291     if (!thdb) return 0;
1292
1293     if (!thdb->teb.queue)
1294         Callout.InitThreadInput16( 0, THREAD_IsWin16(thdb)? 4 : 5 );
1295
1296     if (!thdb->teb.queue)
1297         FIXME_(task)("(): should initialize thread-local queue, expect failure!\n" );
1298
1299     return (HANDLE)thdb->teb.queue;
1300 }
1301
1302 /***********************************************************************
1303  *           SwitchStackTo   (KERNEL.108)
1304  */
1305 void WINAPI SwitchStackTo16( WORD seg, WORD ptr, WORD top )
1306 {
1307     TDB *pTask;
1308     STACK16FRAME *oldFrame, *newFrame;
1309     INSTANCEDATA *pData;
1310     UINT16 copySize;
1311
1312     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
1313     if (!(pData = (INSTANCEDATA *)GlobalLock16( seg ))) return;
1314     TRACE_(task)("old=%04x:%04x new=%04x:%04x\n",
1315                   SELECTOROF( pTask->thdb->cur_stack ),
1316                   OFFSETOF( pTask->thdb->cur_stack ), seg, ptr );
1317
1318     /* Save the old stack */
1319
1320     oldFrame = THREAD_STACK16( pTask->thdb );
1321     /* pop frame + args and push bp */
1322     pData->old_ss_sp   = pTask->thdb->cur_stack + sizeof(STACK16FRAME)
1323                            + 2 * sizeof(WORD);
1324     *(WORD *)PTR_SEG_TO_LIN(pData->old_ss_sp) = oldFrame->bp;
1325     pData->stacktop    = top;
1326     pData->stackmin    = ptr;
1327     pData->stackbottom = ptr;
1328
1329     /* Switch to the new stack */
1330
1331     /* Note: we need to take the 3 arguments into account; otherwise,
1332      * the stack will underflow upon return from this function.
1333      */
1334     copySize = oldFrame->bp - OFFSETOF(pData->old_ss_sp);
1335     copySize += 3 * sizeof(WORD) + sizeof(STACK16FRAME);
1336     pTask->thdb->cur_stack = PTR_SEG_OFF_TO_SEGPTR( seg, ptr - copySize );
1337     newFrame = THREAD_STACK16( pTask->thdb );
1338
1339     /* Copy the stack frame and the local variables to the new stack */
1340
1341     memmove( newFrame, oldFrame, copySize );
1342     newFrame->bp = ptr;
1343     *(WORD *)PTR_SEG_OFF_TO_LIN( seg, ptr ) = 0;  /* clear previous bp */
1344 }
1345
1346
1347 /***********************************************************************
1348  *           SwitchStackBack   (KERNEL.109)
1349  */
1350 void WINAPI SwitchStackBack16( CONTEXT *context )
1351 {
1352     TDB *pTask;
1353     STACK16FRAME *oldFrame, *newFrame;
1354     INSTANCEDATA *pData;
1355
1356     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
1357     if (!(pData = (INSTANCEDATA *)GlobalLock16(SELECTOROF(pTask->thdb->cur_stack))))
1358         return;
1359     if (!pData->old_ss_sp)
1360     {
1361         WARN_(task)("No previous SwitchStackTo\n" );
1362         return;
1363     }
1364     TRACE_(task)("restoring stack %04x:%04x\n",
1365                  SELECTOROF(pData->old_ss_sp), OFFSETOF(pData->old_ss_sp) );
1366
1367     oldFrame = THREAD_STACK16( pTask->thdb );
1368
1369     /* Pop bp from the previous stack */
1370
1371     BP_reg(context) = *(WORD *)PTR_SEG_TO_LIN(pData->old_ss_sp);
1372     pData->old_ss_sp += sizeof(WORD);
1373
1374     /* Switch back to the old stack */
1375
1376     pTask->thdb->cur_stack = pData->old_ss_sp - sizeof(STACK16FRAME);
1377     SS_reg(context)  = SELECTOROF(pData->old_ss_sp);
1378     ESP_reg(context) = OFFSETOF(pData->old_ss_sp) - sizeof(DWORD); /*ret addr*/
1379     pData->old_ss_sp = 0;
1380
1381     /* Build a stack frame for the return */
1382
1383     newFrame = THREAD_STACK16( pTask->thdb );
1384     newFrame->frame32 = oldFrame->frame32;
1385     if (TRACE_ON(relay))
1386     {
1387         newFrame->entry_ip = oldFrame->entry_ip;
1388         newFrame->entry_cs = oldFrame->entry_cs;
1389     }
1390 }
1391
1392
1393 /***********************************************************************
1394  *           GetTaskQueueDS  (KERNEL.118)
1395  */
1396 void WINAPI GetTaskQueueDS16( CONTEXT *context )
1397 {
1398     DS_reg(context) = GlobalHandleToSel16( GetTaskQueue16(0) );
1399 }
1400
1401
1402 /***********************************************************************
1403  *           GetTaskQueueES  (KERNEL.119)
1404  */
1405 void WINAPI GetTaskQueueES16( CONTEXT *context )
1406 {
1407     ES_reg(context) = GlobalHandleToSel16( GetTaskQueue16(0) );
1408 }
1409
1410
1411 /***********************************************************************
1412  *           GetCurrentTask   (KERNEL.36)
1413  */
1414 HTASK16 WINAPI GetCurrentTask(void)
1415 {
1416     return PROCESS_Current()->task;
1417 }
1418
1419 DWORD WINAPI WIN16_GetCurrentTask(void)
1420 {
1421     /* This is the version used by relay code; the first task is */
1422     /* returned in the high word of the result */
1423     return MAKELONG( GetCurrentTask(), hFirstTask );
1424 }
1425
1426
1427 /***********************************************************************
1428  *           GetCurrentPDB   (KERNEL.37)
1429  *
1430  * UNDOC: returns PSP of KERNEL in high word
1431  */
1432 DWORD WINAPI GetCurrentPDB16(void)
1433 {
1434     TDB *pTask;
1435
1436     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1437     return MAKELONG(pTask->hPDB, 0); /* FIXME */
1438 }
1439
1440
1441 /***********************************************************************
1442  *           GetInstanceData   (KERNEL.54)
1443  */
1444 INT16 WINAPI GetInstanceData16( HINSTANCE16 instance, WORD buffer, INT16 len )
1445 {
1446     char *ptr = (char *)GlobalLock16( instance );
1447     if (!ptr || !len) return 0;
1448     if ((int)buffer + len >= 0x10000) len = 0x10000 - buffer;
1449     memcpy( (char *)GlobalLock16(CURRENT_DS) + buffer, ptr + buffer, len );
1450     return len;
1451 }
1452
1453
1454 /***********************************************************************
1455  *           GetExeVersion   (KERNEL.105)
1456  */
1457 WORD WINAPI GetExeVersion16(void)
1458 {
1459     TDB *pTask;
1460
1461     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1462     return pTask->version;
1463 }
1464
1465
1466 /***********************************************************************
1467  *           SetErrorMode16   (KERNEL.107)
1468  */
1469 UINT16 WINAPI SetErrorMode16( UINT16 mode )
1470 {
1471     TDB *pTask;
1472     UINT16 oldMode;
1473
1474     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1475     oldMode = pTask->error_mode;
1476     pTask->error_mode = mode;
1477     pTask->thdb->process->error_mode = mode;
1478     return oldMode;
1479 }
1480
1481
1482 /***********************************************************************
1483  *           SetErrorMode32   (KERNEL32.486)
1484  */
1485 UINT WINAPI SetErrorMode( UINT mode )
1486 {
1487     return SetErrorMode16( (UINT16)mode );
1488 }
1489
1490
1491 /***********************************************************************
1492  *           GetDOSEnvironment   (KERNEL.131)
1493  */
1494 SEGPTR WINAPI GetDOSEnvironment16(void)
1495 {
1496     TDB *pTask;
1497
1498     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1499     return PTR_SEG_OFF_TO_SEGPTR( pTask->pdb.environment, 0 );
1500 }
1501
1502
1503 /***********************************************************************
1504  *           GetNumTasks   (KERNEL.152)
1505  */
1506 UINT16 WINAPI GetNumTasks16(void)
1507 {
1508     return nTaskCount;
1509 }
1510
1511
1512 /***********************************************************************
1513  *           GetTaskDS   (KERNEL.155)
1514  *
1515  * Note: this function apparently returns a DWORD with LOWORD == HIWORD.
1516  * I don't think we need to bother with this.
1517  */
1518 HINSTANCE16 WINAPI GetTaskDS16(void)
1519 {
1520     TDB *pTask;
1521
1522     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1523     return pTask->hInstance;
1524 }
1525
1526 /***********************************************************************
1527  *           GetDummyModuleHandleDS   (KERNEL.602)
1528  */
1529 VOID WINAPI GetDummyModuleHandleDS16( CONTEXT *context )
1530 {
1531     TDB *pTask;
1532     WORD selector;
1533
1534     AX_reg( context ) = 0;
1535     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
1536     if (!(pTask->flags & TDBF_WIN32)) return;
1537
1538     selector = GlobalHandleToSel16( pTask->hModule );
1539     DS_reg( context ) = selector;
1540     AX_reg( context ) = selector;
1541 }
1542
1543 /***********************************************************************
1544  *           IsTask   (KERNEL.320)
1545  */
1546 BOOL16 WINAPI IsTask16( HTASK16 hTask )
1547 {
1548     TDB *pTask;
1549
1550     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return FALSE;
1551     if (GlobalSize16( hTask ) < sizeof(TDB)) return FALSE;
1552     return (pTask->magic == TDB_MAGIC);
1553 }
1554
1555
1556 /***********************************************************************
1557  *           SetTaskSignalProc   (KERNEL.38)
1558  *
1559  * Real 16-bit interface is provided by the THUNK_SetTaskSignalProc.
1560  */
1561 FARPROC16 WINAPI SetTaskSignalProc( HTASK16 hTask, FARPROC16 proc )
1562 {
1563     TDB *pTask;
1564     FARPROC16 oldProc;
1565
1566     if (!hTask) hTask = GetCurrentTask();
1567     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return NULL;
1568     oldProc = (FARPROC16)pTask->userhandler;
1569     pTask->userhandler = (USERSIGNALPROC)proc;
1570     return oldProc;
1571 }
1572
1573
1574 /***********************************************************************
1575  *           SetSigHandler   (KERNEL.140)
1576  */
1577 WORD WINAPI SetSigHandler16( FARPROC16 newhandler, FARPROC16* oldhandler,
1578                            UINT16 *oldmode, UINT16 newmode, UINT16 flag )
1579 {
1580     FIXME_(task)("(%p,%p,%p,%d,%d), unimplemented.\n",
1581           newhandler,oldhandler,oldmode,newmode,flag );
1582
1583     if (flag != 1) return 0;
1584     if (!newmode) newhandler = NULL;  /* Default handler */
1585     if (newmode != 4)
1586     {
1587         TDB *pTask;
1588
1589         if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1590         if (oldmode) *oldmode = pTask->signal_flags;
1591         pTask->signal_flags = newmode;
1592         if (oldhandler) *oldhandler = pTask->sighandler;
1593         pTask->sighandler = newhandler;
1594     }
1595     return 0;
1596 }
1597
1598
1599 /***********************************************************************
1600  *           GlobalNotify   (KERNEL.154)
1601  *
1602  * Note that GlobalNotify does _not_ return the old NotifyProc
1603  * -- contrary to LocalNotify !!
1604  */
1605 VOID WINAPI GlobalNotify16( FARPROC16 proc )
1606 {
1607     TDB *pTask;
1608
1609     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
1610     pTask->discardhandler = proc;
1611 }
1612
1613
1614 /***********************************************************************
1615  *           GetExePtr   (KERNEL.133)
1616  */
1617 static HMODULE16 GetExePtrHelper( HANDLE16 handle, HTASK16 *hTask )
1618 {
1619     char *ptr;
1620     HANDLE16 owner;
1621
1622       /* Check for module handle */
1623
1624     if (!(ptr = GlobalLock16( handle ))) return 0;
1625     if (((NE_MODULE *)ptr)->magic == IMAGE_OS2_SIGNATURE) return handle;
1626
1627       /* Search for this handle inside all tasks */
1628
1629     *hTask = hFirstTask;
1630     while (*hTask)
1631     {
1632         TDB *pTask = (TDB *)GlobalLock16( *hTask );
1633         if ((*hTask == handle) ||
1634             (pTask->hInstance == handle) ||
1635             (pTask->hQueue == handle) ||
1636             (pTask->hPDB == handle)) return pTask->hModule;
1637         *hTask = pTask->hNext;
1638     }
1639
1640       /* Check the owner for module handle */
1641
1642     owner = FarGetOwner16( handle );
1643     if (!(ptr = GlobalLock16( owner ))) return 0;
1644     if (((NE_MODULE *)ptr)->magic == IMAGE_OS2_SIGNATURE) return owner;
1645
1646       /* Search for the owner inside all tasks */
1647
1648     *hTask = hFirstTask;
1649     while (*hTask)
1650     {
1651         TDB *pTask = (TDB *)GlobalLock16( *hTask );
1652         if ((*hTask == owner) ||
1653             (pTask->hInstance == owner) ||
1654             (pTask->hQueue == owner) ||
1655             (pTask->hPDB == owner)) return pTask->hModule;
1656         *hTask = pTask->hNext;
1657     }
1658
1659     return 0;
1660 }
1661
1662 HMODULE16 WINAPI GetExePtr( HANDLE16 handle )
1663 {
1664     HTASK16 dummy;
1665     return GetExePtrHelper( handle, &dummy );
1666 }
1667
1668 void WINAPI WIN16_GetExePtr( CONTEXT *context )
1669 {
1670     WORD *stack = PTR_SEG_OFF_TO_LIN(SS_reg(context), SP_reg(context));
1671     HANDLE16 handle = (HANDLE16)stack[2];
1672     HTASK16 hTask = 0;
1673     HMODULE16 hModule;
1674
1675     hModule = GetExePtrHelper( handle, &hTask );
1676
1677     AX_reg(context) = CX_reg(context) = hModule;
1678     if (hTask) ES_reg(context) = hTask;
1679 }
1680
1681 /***********************************************************************
1682  *           TaskFirst   (TOOLHELP.63)
1683  */
1684 BOOL16 WINAPI TaskFirst16( TASKENTRY *lpte )
1685 {
1686     lpte->hNext = hFirstTask;
1687     return TaskNext16( lpte );
1688 }
1689
1690
1691 /***********************************************************************
1692  *           TaskNext   (TOOLHELP.64)
1693  */
1694 BOOL16 WINAPI TaskNext16( TASKENTRY *lpte )
1695 {
1696     TDB *pTask;
1697     INSTANCEDATA *pInstData;
1698
1699     TRACE_(toolhelp)("(%p): task=%04x\n", lpte, lpte->hNext );
1700     if (!lpte->hNext) return FALSE;
1701     pTask = (TDB *)GlobalLock16( lpte->hNext );
1702     if (!pTask || pTask->magic != TDB_MAGIC) return FALSE;
1703     pInstData = (INSTANCEDATA *)PTR_SEG_OFF_TO_LIN( pTask->hInstance, 0 );
1704     lpte->hTask         = lpte->hNext;
1705     lpte->hTaskParent   = pTask->hParent;
1706     lpte->hInst         = pTask->hInstance;
1707     lpte->hModule       = pTask->hModule;
1708     lpte->wSS           = SELECTOROF( pTask->thdb->cur_stack );
1709     lpte->wSP           = OFFSETOF( pTask->thdb->cur_stack );
1710     lpte->wStackTop     = pInstData->stacktop;
1711     lpte->wStackMinimum = pInstData->stackmin;
1712     lpte->wStackBottom  = pInstData->stackbottom;
1713     lpte->wcEvents      = pTask->nEvents;
1714     lpte->hQueue        = pTask->hQueue;
1715     strncpy( lpte->szModule, pTask->module_name, 8 );
1716     lpte->szModule[8]   = '\0';
1717     lpte->wPSPOffset    = 0x100;  /*??*/
1718     lpte->hNext         = pTask->hNext;
1719     return TRUE;
1720 }
1721
1722
1723 /***********************************************************************
1724  *           TaskFindHandle   (TOOLHELP.65)
1725  */
1726 BOOL16 WINAPI TaskFindHandle16( TASKENTRY *lpte, HTASK16 hTask )
1727 {
1728     lpte->hNext = hTask;
1729     return TaskNext16( lpte );
1730 }
1731
1732
1733 /***********************************************************************
1734  *           GetAppCompatFlags16   (KERNEL.354)
1735  */
1736 DWORD WINAPI GetAppCompatFlags16( HTASK16 hTask )
1737 {
1738     return GetAppCompatFlags( hTask );
1739 }
1740
1741
1742 /***********************************************************************
1743  *           GetAppCompatFlags32   (USER32.206)
1744  */
1745 DWORD WINAPI GetAppCompatFlags( HTASK hTask )
1746 {
1747     TDB *pTask;
1748
1749     if (!hTask) hTask = GetCurrentTask();
1750     if (!(pTask=(TDB *)GlobalLock16( (HTASK16)hTask ))) return 0;
1751     if (GlobalSize16(hTask) < sizeof(TDB)) return 0;
1752     return pTask->compat_flags;
1753 }