src/os2/thread.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/os2/thread.cpp
   3 // Purpose:     wxThread Implementation
   4 // Author:      Original from Wolfram Gloger/Guilhem Lavaux/David Webster
   5 // Modified by: Stefan Neis
   6 // Created:     04/22/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Stefan Neis (2003)
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ----------------------------------------------------------------------------
  13 // headers
  14 // ----------------------------------------------------------------------------
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #if wxUSE_THREADS
  20
  21 #include "wx/thread.h"
  22
  23 #ifndef WX_PRECOMP
  24     #include "wx/intl.h"
  25     #include "wx/log.h"
  26     #include "wx/app.h"
  27     #include "wx/module.h"
  28 #endif //WX_PRECOMP
  29
  30 #include "wx/apptrait.h"
  31 #include "wx/utils.h"
  32
  33 #include <stdio.h>
  34
  35 #define INCL_DOSSEMAPHORES
  36 #define INCL_DOSPROCESS
  37 #define INCL_DOSMISC
  38 #define INCL_ERRORS
  39 #include <os2.h>
  40 #ifndef __EMX__
  41 #include <bseerr.h>
  42 #endif
  43 // the possible states of the thread ("=>" shows all possible transitions from
  44 // this state)
  45 enum wxThreadState
  46 {
  47     STATE_NEW,          // didn't start execution yet (=> RUNNING)
  48     STATE_RUNNING,      // thread is running (=> PAUSED, CANCELED)
  49     STATE_PAUSED,       // thread is temporarily suspended (=> RUNNING)
  50     STATE_CANCELED,     // thread should terminate a.s.a.p. (=> EXITED)
  51     STATE_EXITED        // thread is terminating
  52 };
  53
  54 // ----------------------------------------------------------------------------
  55 // this module's globals
  56 // ----------------------------------------------------------------------------
  57
  58 // id of the main thread - the one which can call GUI functions without first
  59 // calling wxMutexGuiEnter()
  60 static ULONG                        s_ulIdMainThread = 1;
  61 wxMutex*                            p_wxMainMutex;
  62
  63 // OS2 substitute for Tls pointer the current parent thread object
  64 wxThread*                           m_pThread;    // pointer to the wxWidgets thread object
  65
  66 // if it's false, some secondary thread is holding the GUI lock
  67 static bool gs_bGuiOwnedByMainThread = true;
  68
  69 // critical section which controls access to all GUI functions: any secondary
  70 // thread (i.e. except the main one) must enter this crit section before doing
  71 // any GUI calls
  72 static wxCriticalSection *gs_pCritsectGui = NULL;
  73
  74 // critical section which protects s_nWaitingForGui variable
  75 static wxCriticalSection *gs_pCritsectWaitingForGui = NULL;
  76
  77 // number of threads waiting for GUI in wxMutexGuiEnter()
  78 static size_t gs_nWaitingForGui = 0;
  79
  80 // are we waiting for a thread termination?
  81 static bool gs_bWaitingForThread = false;
  82
  83 // ============================================================================
  84 // OS/2 implementation of thread and related classes
  85 // ============================================================================
  86
  87 // ----------------------------------------------------------------------------
  88 // wxMutex implementation
  89 // ----------------------------------------------------------------------------
  90 class wxMutexInternal
  91 {
  92 public:
  93     wxMutexInternal(wxMutexType mutexType);
  94     ~wxMutexInternal();
  95
  96     bool IsOk() const { return m_vMutex != NULL; }
  97
  98     wxMutexError Lock() { return LockTimeout(SEM_INDEFINITE_WAIT); }
  99     wxMutexError TryLock() { return LockTimeout(SEM_IMMEDIATE_RETURN); }
 100     wxMutexError Unlock();
 101
 102 private:
 103     wxMutexError LockTimeout(ULONG ulMilliseconds);
 104     HMTX                            m_vMutex;
 105 };
 106
 107 // all mutexes are "pseudo-"recursive under OS2 so we don't use mutexType
 108 // (Calls to DosRequestMutexSem and DosReleaseMutexSem can be nested, but
 109 //  the request count for a semaphore cannot exceed 65535. If an attempt is
 110 //  made to exceed this number, ERROR_TOO_MANY_SEM_REQUESTS is returned.)
 111 wxMutexInternal::wxMutexInternal(wxMutexType WXUNUSED(eMutexType))
 112 {
 113     APIRET ulrc = ::DosCreateMutexSem(NULL, &m_vMutex, 0L, FALSE);
 114     if (ulrc != 0)
 115     {
 116         wxLogSysError(_("Can not create mutex."));
 117         m_vMutex = NULL;
 118     }
 119 }
 120
 121 wxMutexInternal::~wxMutexInternal()
 122 {
 123     if (m_vMutex)
 124     {
 125         if (::DosCloseMutexSem(m_vMutex))
 126             wxLogLastError(_T("DosCloseMutexSem(mutex)"));
 127     }
 128 }
 129
 130 wxMutexError wxMutexInternal::LockTimeout(ULONG ulMilliseconds)
 131 {
 132     APIRET                          ulrc;
 133
 134     ulrc = ::DosRequestMutexSem(m_vMutex, ulMilliseconds);
 135
 136     switch (ulrc)
 137     {
 138         case ERROR_TIMEOUT:
 139         case ERROR_TOO_MANY_SEM_REQUESTS:
 140             return wxMUTEX_BUSY;
 141
 142         case NO_ERROR:
 143             // ok
 144             break;
 145
 146         case ERROR_INVALID_HANDLE:
 147         case ERROR_INTERRUPT:
 148         case ERROR_SEM_OWNER_DIED:
 149             wxLogSysError(_("Couldn't acquire a mutex lock"));
 150             return wxMUTEX_MISC_ERROR;
 151
 152         default:
 153             wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock"));
 154             return wxMUTEX_MISC_ERROR;
 155      }
 156     return wxMUTEX_NO_ERROR;
 157 }
 158
 159 wxMutexError wxMutexInternal::Unlock()
 160 {
 161     APIRET                          ulrc;
 162
 163     ulrc = ::DosReleaseMutexSem(m_vMutex);
 164     if (ulrc != 0)
 165     {
 166         wxLogSysError(_("Couldn't release a mutex"));
 167         return wxMUTEX_MISC_ERROR;
 168     }
 169     return wxMUTEX_NO_ERROR;
 170 }
 171
 172 // --------------------------------------------------------------------------
 173 // wxSemaphore
 174 // --------------------------------------------------------------------------
 175
 176 // a trivial wrapper around OS2 event semaphore
 177 class wxSemaphoreInternal
 178 {
 179 public:
 180     wxSemaphoreInternal(int initialcount, int maxcount);
 181     ~wxSemaphoreInternal();
 182
 183     bool IsOk() const { return m_vEvent != NULL; }
 184
 185     wxSemaError Wait() { return WaitTimeout(SEM_INDEFINITE_WAIT); }
 186     wxSemaError TryWait() { return WaitTimeout(SEM_IMMEDIATE_RETURN); }
 187     wxSemaError WaitTimeout(unsigned long milliseconds);
 188
 189     wxSemaError Post();
 190
 191 private:
 192     HEV m_vEvent;
 193     HMTX m_vMutex;
 194     int m_count;
 195     int m_maxcount;
 196 };
 197
 198 wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount)
 199 {
 200     APIRET ulrc;
 201     if ( maxcount == 0 )
 202     {
 203         // make it practically infinite
 204         maxcount = INT_MAX;
 205     }
 206
 207     m_count = initialcount;
 208     m_maxcount = maxcount;
 209     ulrc = ::DosCreateMutexSem(NULL, &m_vMutex, 0L, FALSE);
 210     if (ulrc != 0)
 211     {
 212         wxLogLastError(_T("DosCreateMutexSem()"));
 213         m_vMutex = NULL;
 214         m_vEvent = NULL;
 215         return;
 216     }
 217     ulrc = ::DosCreateEventSem(NULL, &m_vEvent, 0L, FALSE);
 218     if ( ulrc != 0)
 219     {
 220         wxLogLastError(_T("DosCreateEventSem()"));
 221         ::DosCloseMutexSem(m_vMutex);
 222         m_vMutex = NULL;
 223         m_vEvent = NULL;
 224     }
 225     if (initialcount)
 226         ::DosPostEventSem(m_vEvent);
 227 }
 228
 229 wxSemaphoreInternal::~wxSemaphoreInternal()
 230 {
 231     if ( m_vEvent )
 232     {
 233         if ( ::DosCloseEventSem(m_vEvent) )
 234         {
 235             wxLogLastError(_T("DosCloseEventSem(semaphore)"));
 236         }
 237         if ( ::DosCloseMutexSem(m_vMutex) )
 238         {
 239             wxLogLastError(_T("DosCloseMutexSem(semaphore)"));
 240         }
 241         else
 242             m_vEvent = NULL;
 243     }
 244 }
 245
 246 wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long ulMilliseconds)
 247 {
 248     APIRET ulrc;
 249     do {
 250         ulrc = ::DosWaitEventSem(m_vEvent, ulMilliseconds );
 251         switch ( ulrc )
 252         {
 253             case NO_ERROR:
 254                 break;
 255
 256             case ERROR_TIMEOUT:
 257                 if (ulMilliseconds == SEM_IMMEDIATE_RETURN)
 258                     return wxSEMA_BUSY;
 259                 else
 260                     return wxSEMA_TIMEOUT;
 261
 262             default:
 263                 wxLogLastError(_T("DosWaitEventSem(semaphore)"));
 264                 return wxSEMA_MISC_ERROR;
 265         }
 266         ulrc = :: DosRequestMutexSem(m_vMutex, ulMilliseconds);
 267         switch ( ulrc )
 268         {
 269             case NO_ERROR:
 270                 // ok
 271                 break;
 272
 273             case ERROR_TIMEOUT:
 274             case ERROR_TOO_MANY_SEM_REQUESTS:
 275                 if (ulMilliseconds == SEM_IMMEDIATE_RETURN)
 276                     return wxSEMA_BUSY;
 277                 else
 278                     return wxSEMA_TIMEOUT;
 279
 280             default:
 281                 wxFAIL_MSG(wxT("DosRequestMutexSem(mutex)"));
 282                 return wxSEMA_MISC_ERROR;
 283         }
 284         bool OK = false;
 285         if (m_count > 0)
 286         {
 287             m_count--;
 288             OK = true;
 289         }
 290         else
 291         {
 292             ULONG ulPostCount;
 293             ::DosResetEventSem(m_vEvent, &ulPostCount);
 294         }
 295         ::DosReleaseMutexSem(m_vMutex);
 296         if (OK)
 297             return wxSEMA_NO_ERROR;
 298     } while (ulMilliseconds == SEM_INDEFINITE_WAIT);
 299
 300     if (ulMilliseconds == SEM_IMMEDIATE_RETURN)
 301         return wxSEMA_BUSY;
 302     return wxSEMA_TIMEOUT;
 303 }
 304
 305 wxSemaError wxSemaphoreInternal::Post()
 306 {
 307     APIRET ulrc;
 308     ulrc = ::DosRequestMutexSem(m_vMutex, SEM_INDEFINITE_WAIT);
 309     if (ulrc != NO_ERROR)
 310         return wxSEMA_MISC_ERROR;
 311     bool OK = false;
 312     if (m_count < m_maxcount)
 313     {
 314         m_count++;
 315         ulrc = ::DosPostEventSem(m_vEvent);
 316         OK = true;
 317     }
 318     ::DosReleaseMutexSem(m_vMutex);
 319     if (!OK)
 320         return wxSEMA_OVERFLOW;
 321     if ( ulrc != NO_ERROR && ulrc != ERROR_ALREADY_POSTED )
 322     {
 323         wxLogLastError(_T("DosPostEventSem(semaphore)"));
 324
 325         return wxSEMA_MISC_ERROR;
 326     }
 327
 328     return wxSEMA_NO_ERROR;
 329 }
 330
 331 // ----------------------------------------------------------------------------
 332 // wxThread implementation
 333 // ----------------------------------------------------------------------------
 334
 335 // wxThreadInternal class
 336 // ----------------------
 337
 338 class wxThreadInternal
 339 {
 340 public:
 341     inline wxThreadInternal()
 342     {
 343         m_hThread = 0;
 344         m_eState = STATE_NEW;
 345         m_nPriority = WXTHREAD_DEFAULT_PRIORITY;
 346     }
 347
 348     ~wxThreadInternal()
 349     {
 350         m_hThread = 0;
 351     }
 352
 353     // create a new (suspended) thread (for the given thread object)
 354     bool Create( wxThread*    pThread
 355                 ,unsigned int uStackSize
 356                );
 357
 358     // suspend/resume/terminate
 359     bool Suspend();
 360     bool Resume();
 361     inline void Cancel() { m_eState = STATE_CANCELED; }
 362
 363     // thread state
 364     inline void SetState(wxThreadState eState) { m_eState = eState; }
 365     inline wxThreadState GetState() const { return m_eState; }
 366
 367     // thread priority
 368     void                SetPriority(unsigned int nPriority);
 369     inline unsigned int GetPriority() const { return m_nPriority; }
 370
 371     // thread handle and id
 372     inline TID GetHandle() const { return m_hThread; }
 373     TID  GetId() const { return m_hThread; }
 374
 375     // thread function
 376     static void OS2ThreadStart(void* pParam);
 377
 378 private:
 379     // Threads in OS/2 have only an ID, so m_hThread is both it's handle and ID
 380     // PM also has no real Tls mechanism to index pointers by so we'll just
 381     // keep track of the wxWidgets parent object here.
 382     TID                             m_hThread;    // handle and ID of the thread
 383     wxThreadState                   m_eState;     // state, see wxThreadState enum
 384     unsigned int                    m_nPriority;  // thread priority in "wx" units
 385 };
 386
 387 void wxThreadInternal::OS2ThreadStart( void * pParam )
 388 {
 389     DWORD dwRet;
 390     bool bWasCancelled;
 391
 392     wxThread *pThread = (wxThread *)pParam;
 393
 394     // first of all, wait for the thread to be started.
 395     pThread->m_critsect.Enter();
 396     pThread->m_critsect.Leave();
 397     // Now check whether we hadn't been cancelled already and don't
 398     // start the user code at all in this case.
 399     if ( pThread->m_internal->GetState() == STATE_EXITED )
 400     {
 401         dwRet = (DWORD)-1;
 402         bWasCancelled = true;
 403     }
 404     else // do run thread
 405     {
 406         wxAppTraits *traits = wxTheApp ? wxTheApp->GetTraits() : NULL;
 407         unsigned long ulHab;
 408         if (traits)
 409             traits->InitializeGui(ulHab);
 410         dwRet = (DWORD)pThread->Entry();
 411         if (traits)
 412             traits->TerminateGui(ulHab);
 413
 414         // enter m_critsect before changing the thread state
 415         pThread->m_critsect.Enter();
 416
 417         bWasCancelled = pThread->m_internal->GetState() == STATE_CANCELED;
 418
 419         pThread->m_internal->SetState(STATE_EXITED);
 420         pThread->m_critsect.Leave();
 421     }
 422     pThread->OnExit();
 423
 424     // if the thread was cancelled (from Delete()), then it the handle is still
 425     // needed there
 426     if (pThread->IsDetached() && !bWasCancelled)
 427     {
 428         // auto delete
 429         delete pThread;
 430     }
 431     //else: the joinable threads handle will be closed when Wait() is done
 432     return;
 433 }
 434
 435 void wxThreadInternal::SetPriority(
 436   unsigned int                      nPriority
 437 )
 438 {
 439     // translate wxWidgets priority to the PM one
 440     ULONG                           ulOS2_PriorityClass;
 441     ULONG                           ulOS2_SubPriority;
 442     ULONG                           ulrc;
 443
 444     m_nPriority = nPriority;
 445     if (m_nPriority <= 25)
 446         ulOS2_PriorityClass = PRTYC_IDLETIME;
 447     else if (m_nPriority <= 50)
 448         ulOS2_PriorityClass = PRTYC_REGULAR;
 449     else if (m_nPriority <= 75)
 450         ulOS2_PriorityClass = PRTYC_TIMECRITICAL;
 451     else if (m_nPriority <= 100)
 452         ulOS2_PriorityClass = PRTYC_FOREGROUNDSERVER;
 453     else
 454     {
 455         wxFAIL_MSG(wxT("invalid value of thread priority parameter"));
 456         ulOS2_PriorityClass = PRTYC_REGULAR;
 457     }
 458     ulOS2_SubPriority = (ULONG) (((m_nPriority - 1) % 25 + 1) * 31.0 / 25);
 459     ulrc = ::DosSetPriority( PRTYS_THREAD
 460                             ,ulOS2_PriorityClass
 461                             ,ulOS2_SubPriority
 462                             ,(ULONG)m_hThread
 463                            );
 464     if (ulrc != 0)
 465     {
 466         wxLogSysError(_("Can't set thread priority"));
 467     }
 468 }
 469
 470 bool wxThreadInternal::Create( wxThread* pThread,
 471                                unsigned int uStackSize)
 472 {
 473     int tid;
 474
 475     if (!uStackSize)
 476         uStackSize = 131072;
 477
 478     pThread->m_critsect.Enter();
 479     tid = _beginthread(wxThreadInternal::OS2ThreadStart,
 480                              NULL, uStackSize, pThread);
 481     if(tid == -1)
 482     {
 483         wxLogSysError(_("Can't create thread"));
 484
 485         return false;
 486     }
 487     m_hThread = tid;
 488     if (m_nPriority != WXTHREAD_DEFAULT_PRIORITY)
 489     {
 490         SetPriority(m_nPriority);
 491     }
 492
 493     return true;
 494 }
 495
 496 bool wxThreadInternal::Suspend()
 497 {
 498     ULONG ulrc = ::DosSuspendThread(m_hThread);
 499
 500     if (ulrc != 0)
 501     {
 502         wxLogSysError(_("Can not suspend thread %lu"), m_hThread);
 503         return false;
 504     }
 505     m_eState = STATE_PAUSED;
 506
 507     return true;
 508 }
 509
 510 bool wxThreadInternal::Resume()
 511 {
 512     ULONG ulrc = ::DosResumeThread(m_hThread);
 513
 514     if (ulrc != 0)
 515     {
 516         wxLogSysError(_("Can not resume thread %lu"), m_hThread);
 517         return false;
 518     }
 519
 520     // don't change the state from STATE_EXITED because it's special and means
 521     // we are going to terminate without running any user code - if we did it,
 522     // the codei n Delete() wouldn't work
 523     if ( m_eState != STATE_EXITED )
 524     {
 525         m_eState = STATE_RUNNING;
 526     }
 527
 528     return true;
 529 }
 530
 531 // static functions
 532 // ----------------
 533
 534 wxThread *wxThread::This()
 535 {
 536     wxThread*                       pThread = m_pThread;
 537     return pThread;
 538 }
 539
 540 bool wxThread::IsMain()
 541 {
 542     PTIB ptib;
 543     PPIB ppib;
 544
 545     ::DosGetInfoBlocks(&ptib, &ppib);
 546
 547     if (ptib->tib_ptib2->tib2_ultid == s_ulIdMainThread)
 548         return true;
 549
 550     return false;
 551 }
 552
 553 #ifdef Yield
 554     #undef Yield
 555 #endif
 556
 557 void wxThread::Yield()
 558 {
 559     ::DosSleep(0);
 560 }
 561
 562 void wxThread::Sleep(
 563   unsigned long                     ulMilliseconds
 564 )
 565 {
 566     ::DosSleep(ulMilliseconds);
 567 }
 568
 569 int wxThread::GetCPUCount()
 570 {
 571     ULONG CPUCount;
 572     APIRET ulrc;
 573     ulrc = ::DosQuerySysInfo(26, 26, (void *)&CPUCount, sizeof(ULONG));
 574     // QSV_NUMPROCESSORS(26) is typically not defined in header files
 575
 576     if (ulrc != 0)
 577         CPUCount = 1;
 578
 579     return CPUCount;
 580 }
 581
 582 unsigned long wxThread::GetCurrentId()
 583 {
 584     PTIB                            ptib;
 585     PPIB                            ppib;
 586
 587     ::DosGetInfoBlocks(&ptib, &ppib);
 588     return (unsigned long) ptib->tib_ptib2->tib2_ultid;
 589 }
 590
 591 bool wxThread::SetConcurrency(size_t level)
 592 {
 593     wxASSERT_MSG( IsMain(), _T("should only be called from the main thread") );
 594
 595     // ok only for the default one
 596     if ( level == 0 )
 597         return 0;
 598
 599     // Don't know how to realize this on OS/2.
 600     return level == 1;
 601 }
 602
 603 // ctor and dtor
 604 // -------------
 605
 606 wxThread::wxThread(wxThreadKind kind)
 607 {
 608     m_internal = new wxThreadInternal();
 609
 610     m_isDetached = kind == wxTHREAD_DETACHED;
 611 }
 612
 613 wxThread::~wxThread()
 614 {
 615     delete m_internal;
 616 }
 617
 618 // create/start thread
 619 // -------------------
 620
 621 wxThreadError wxThread::Create(
 622   unsigned int                      uStackSize
 623 )
 624 {
 625     wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect);
 626
 627     if ( !m_internal->Create(this, uStackSize) )
 628         return wxTHREAD_NO_RESOURCE;
 629
 630     return wxTHREAD_NO_ERROR;
 631 }
 632
 633 wxThreadError wxThread::Run()
 634 {
 635     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 636
 637     if ( m_internal->GetState() != STATE_NEW )
 638     {
 639         // actually, it may be almost any state at all, not only STATE_RUNNING
 640         return wxTHREAD_RUNNING;
 641     }
 642     return Resume();
 643 }
 644
 645 // suspend/resume thread
 646 // ---------------------
 647
 648 wxThreadError wxThread::Pause()
 649 {
 650     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 651
 652     return m_internal->Suspend() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR;
 653 }
 654
 655 wxThreadError wxThread::Resume()
 656 {
 657     if (m_internal->GetState() == STATE_NEW)
 658     {
 659         m_internal->SetState(STATE_RUNNING);
 660         m_critsect.Leave();
 661         return wxTHREAD_NO_ERROR;
 662     }
 663
 664     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 665
 666     return m_internal->Resume() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR;
 667 }
 668
 669 // stopping thread
 670 // ---------------
 671
 672 wxThread::ExitCode wxThread::Wait()
 673 {
 674     // although under Windows we can wait for any thread, it's an error to
 675     // wait for a detached one in wxWin API
 676     wxCHECK_MSG( !IsDetached(), (ExitCode)-1,
 677                  _T("can't wait for detached thread") );
 678     ExitCode rc = (ExitCode)-1;
 679     (void)Delete(&rc);
 680     return(rc);
 681 }
 682
 683 wxThreadError wxThread::Delete(ExitCode *pRc)
 684 {
 685     ExitCode rc = 0;
 686
 687     // Delete() is always safe to call, so consider all possible states
 688
 689     // we might need to resume the thread, but we might also not need to cancel
 690     // it if it doesn't run yet
 691     bool shouldResume = false,
 692          shouldCancel = true,
 693          isRunning = false;
 694
 695     // check if the thread already started to run
 696     {
 697         wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 698
 699         if ( m_internal->GetState() == STATE_NEW )
 700         {
 701             // WinThreadStart() will see it and terminate immediately, no need
 702             // to cancel the thread - but we still need to resume it to let it
 703             // run
 704             m_internal->SetState(STATE_EXITED);
 705
 706             Resume();   // it knows about STATE_EXITED special case
 707
 708             shouldCancel = false;
 709             isRunning = true;
 710
 711             // shouldResume is correctly set to false here
 712         }
 713         else
 714         {
 715             shouldResume = IsPaused();
 716         }
 717     }
 718
 719     // resume the thread if it is paused
 720     if ( shouldResume )
 721         Resume();
 722
 723     TID hThread = m_internal->GetHandle();
 724
 725     if ( isRunning || IsRunning())
 726     {
 727         if (IsMain())
 728         {
 729             // set flag for wxIsWaitingForThread()
 730             gs_bWaitingForThread = true;
 731         }
 732
 733         // ask the thread to terminate
 734         if ( shouldCancel )
 735         {
 736             wxCriticalSectionLocker lock(m_critsect);
 737
 738             m_internal->Cancel();
 739         }
 740
 741 #if 0
 742         // we can't just wait for the thread to terminate because it might be
 743         // calling some GUI functions and so it will never terminate before we
 744         // process the Windows messages that result from these functions
 745         DWORD result = 0;       // suppress warnings from broken compilers
 746         do
 747         {
 748             if ( IsMain() )
 749             {
 750                 // give the thread we're waiting for chance to do the GUI call
 751                 // it might be in
 752                 if ( (gs_nWaitingForGui > 0) && wxGuiOwnedByMainThread() )
 753                 {
 754                     wxMutexGuiLeave();
 755                 }
 756             }
 757
 758             result = ::DosWaitThread(&hThread, DCWW_NOWAIT);
 759             // FIXME: We ought to have a message processing loop here!!
 760
 761             switch ( result )
 762             {
 763                 case ERROR_INTERRUPT:
 764                 case ERROR_THREAD_NOT_TERMINATED:
 765                     break;
 766                 case ERROR_INVALID_THREADID:
 767                 case NO_ERROR:
 768                     // thread we're waiting for just terminated
 769                     // or even does not exist any more.
 770                     result = NO_ERROR;
 771                     break;
 772                 default:
 773                     wxFAIL_MSG(wxT("unexpected result of DosWaitThread"));
 774             }
 775             if ( IsMain() )
 776             {
 777                 // event processing - needed if we are the main thread
 778                 // to give other threads a chance to do remaining GUI
 779                 // processing and terminate cleanly.
 780                 wxTheApp->HandleSockets();
 781                 if (wxTheApp->Pending())
 782                   if ( !wxTheApp->DoMessage() )
 783                   {
 784                       // WM_QUIT received: kill the thread
 785                       Kill();
 786
 787                       return wxTHREAD_KILLED;
 788                   }
 789                   else
 790                     wxUsleep(10);
 791             }
 792             else
 793                 wxUsleep(10);
 794         } while ( result != NO_ERROR );
 795 #else // !wxUSE_GUI
 796         // simply wait for the thread to terminate
 797         //
 798         // OTOH, even console apps create windows (in wxExecute, for WinSock
 799         // &c), so may be use MsgWaitForMultipleObject() too here?
 800         if ( ::DosWaitThread(&hThread, DCWW_WAIT) != NO_ERROR )
 801         {
 802             wxFAIL_MSG(wxT("unexpected result of DosWaitThread"));
 803         }
 804 #endif // wxUSE_GUI/!wxUSE_GUI
 805
 806         if ( IsMain() )
 807         {
 808             gs_bWaitingForThread = false;
 809         }
 810     }
 811
 812 #if 0
 813     // although the thread might be already in the EXITED state it might not
 814     // have terminated yet and so we are not sure that it has actually
 815     // terminated if the "if" above hadn't been taken
 816     do
 817     {
 818         if ( !::GetExitCodeThread(hThread, (LPDWORD)&rc) )
 819         {
 820             wxLogLastError(wxT("GetExitCodeThread"));
 821
 822             rc = (ExitCode)-1;
 823         }
 824     } while ( (DWORD)rc == STILL_ACTIVE );
 825 #endif
 826
 827     if ( IsDetached() )
 828     {
 829         // if the thread exits normally, this is done in WinThreadStart, but in
 830         // this case it would have been too early because
 831         // MsgWaitForMultipleObject() would fail if the thread handle was
 832         // closed while we were waiting on it, so we must do it here
 833         delete this;
 834     }
 835
 836     if ( pRc )
 837         *pRc = rc;
 838
 839     return rc == (ExitCode)-1 ? wxTHREAD_MISC_ERROR : wxTHREAD_NO_ERROR;
 840 }
 841
 842 wxThreadError wxThread::Kill()
 843 {
 844     if (!IsRunning())
 845         return wxTHREAD_NOT_RUNNING;
 846
 847     ::DosKillThread(m_internal->GetHandle());
 848     if (IsDetached())
 849     {
 850         delete this;
 851     }
 852     return wxTHREAD_NO_ERROR;
 853 }
 854
 855 void wxThread::Exit(ExitCode WXUNUSED(pStatus))
 856 {
 857     delete this;
 858     _endthread();
 859     wxFAIL_MSG(wxT("Couldn't return from DosExit()!"));
 860 }
 861
 862 void wxThread::SetPriority(
 863   unsigned int                      nPrio
 864 )
 865 {
 866     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 867
 868     m_internal->SetPriority(nPrio);
 869 }
 870
 871 unsigned int wxThread::GetPriority() const
 872 {
 873     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 874
 875     return m_internal->GetPriority();
 876 }
 877
 878 unsigned long wxThread::GetId() const
 879 {
 880     wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast
 881
 882     return (unsigned long)m_internal->GetId();
 883 }
 884
 885 bool wxThread::IsRunning() const
 886 {
 887     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 888
 889     return(m_internal->GetState() == STATE_RUNNING);
 890 }
 891
 892 bool wxThread::IsAlive() const
 893 {
 894     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 895
 896     return (m_internal->GetState() == STATE_RUNNING) ||
 897            (m_internal->GetState() == STATE_PAUSED);
 898 }
 899
 900 bool wxThread::IsPaused() const
 901 {
 902     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 903
 904     return (m_internal->GetState() == STATE_PAUSED);
 905 }
 906
 907 bool wxThread::TestDestroy()
 908 {
 909     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 910
 911     return m_internal->GetState() == STATE_CANCELED;
 912 }
 913
 914 // ----------------------------------------------------------------------------
 915 // Automatic initialization for thread module
 916 // ----------------------------------------------------------------------------
 917
 918 class wxThreadModule : public wxModule
 919 {
 920 public:
 921     virtual bool OnInit();
 922     virtual void OnExit();
 923
 924 private:
 925     DECLARE_DYNAMIC_CLASS(wxThreadModule)
 926 };
 927
 928 IMPLEMENT_DYNAMIC_CLASS(wxThreadModule, wxModule)
 929
 930 bool wxThreadModule::OnInit()
 931 {
 932     gs_pCritsectWaitingForGui = new wxCriticalSection();
 933
 934     gs_pCritsectGui = new wxCriticalSection();
 935     gs_pCritsectGui->Enter();
 936
 937     PTIB ptib;
 938     PPIB ppib;
 939
 940     ::DosGetInfoBlocks(&ptib, &ppib);
 941
 942     s_ulIdMainThread = ptib->tib_ptib2->tib2_ultid;
 943     return true;
 944 }
 945
 946 void wxThreadModule::OnExit()
 947 {
 948     if (gs_pCritsectGui)
 949     {
 950         gs_pCritsectGui->Leave();
 951 #if (!(defined(__VISAGECPP__) && (__IBMCPP__ < 400 || __IBMC__ < 400 )))
 952         delete gs_pCritsectGui;
 953 #endif
 954         gs_pCritsectGui = NULL;
 955     }
 956
 957 #if (!(defined(__VISAGECPP__) && (__IBMCPP__ < 400 || __IBMC__ < 400 )))
 958     wxDELETE(gs_pCritsectWaitingForGui);
 959 #endif
 960 }
 961
 962 // ----------------------------------------------------------------------------
 963 // Helper functions
 964 // ----------------------------------------------------------------------------
 965
 966 // wake up the main thread if it's in ::GetMessage()
 967 void WXDLLEXPORT wxWakeUpMainThread()
 968 {
 969 #if 0
 970     if ( !::WinPostQueueMsg(wxTheApp->m_hMq, WM_NULL, 0, 0) )
 971     {
 972         // should never happen
 973         wxLogLastError(wxT("WinPostMessage(WM_NULL)"));
 974     }
 975 #endif
 976 }
 977
 978 void WXDLLEXPORT wxMutexGuiEnter()
 979 {
 980     // this would dead lock everything...
 981     wxASSERT_MSG( !wxThread::IsMain(),
 982                   wxT("main thread doesn't want to block in wxMutexGuiEnter()!") );
 983
 984     // the order in which we enter the critical sections here is crucial!!
 985
 986     // set the flag telling to the main thread that we want to do some GUI
 987     {
 988         wxCriticalSectionLocker enter(*gs_pCritsectWaitingForGui);
 989
 990         gs_nWaitingForGui++;
 991     }
 992
 993     wxWakeUpMainThread();
 994
 995     // now we may block here because the main thread will soon let us in
 996     // (during the next iteration of OnIdle())
 997     gs_pCritsectGui->Enter();
 998 }
 999
1000 void WXDLLEXPORT wxMutexGuiLeave()
1001 {
1002     wxCriticalSectionLocker enter(*gs_pCritsectWaitingForGui);
1003
1004     if ( wxThread::IsMain() )
1005     {
1006         gs_bGuiOwnedByMainThread = false;
1007     }
1008     else
1009     {
1010         // decrement the number of waiters now
1011         wxASSERT_MSG(gs_nWaitingForGui > 0,
1012                       wxT("calling wxMutexGuiLeave() without entering it first?") );
1013
1014         gs_nWaitingForGui--;
1015
1016         wxWakeUpMainThread();
1017     }
1018
1019     gs_pCritsectGui->Leave();
1020 }
1021
1022 void WXDLLEXPORT wxMutexGuiLeaveOrEnter()
1023 {
1024     wxASSERT_MSG( wxThread::IsMain(),
1025                   wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") );
1026
1027     wxCriticalSectionLocker enter(*gs_pCritsectWaitingForGui);
1028
1029     if (gs_nWaitingForGui == 0)
1030     {
1031         // no threads are waiting for GUI - so we may acquire the lock without
1032         // any danger (but only if we don't already have it)
1033         if (!wxGuiOwnedByMainThread())
1034         {
1035             gs_pCritsectGui->Enter();
1036
1037             gs_bGuiOwnedByMainThread = true;
1038         }
1039         //else: already have it, nothing to do
1040     }
1041     else
1042     {
1043         // some threads are waiting, release the GUI lock if we have it
1044         if (wxGuiOwnedByMainThread())
1045         {
1046             wxMutexGuiLeave();
1047         }
1048         //else: some other worker thread is doing GUI
1049     }
1050 }
1051
1052 bool WXDLLEXPORT wxGuiOwnedByMainThread()
1053 {
1054     return gs_bGuiOwnedByMainThread;
1055 }
1056
1057 bool WXDLLEXPORT wxIsWaitingForThread()
1058 {
1059     return gs_bWaitingForThread;
1060 }
1061
1062 // ----------------------------------------------------------------------------
1063 // include common implementation code
1064 // ----------------------------------------------------------------------------
1065
1066 #include "wx/thrimpl.cpp"
1067
1068 #endif
1069   // wxUSE_THREADS