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 //
  10 // Licence:     wxWindows licence
  11 /////////////////////////////////////////////////////////////////////////////
  12
  13 #ifdef __GNUG__
  14     #pragma implementation "thread.h"
  15 #endif
  16
  17 // ----------------------------------------------------------------------------
  18 // headers
  19 // ----------------------------------------------------------------------------
  20
  21 // For compilers that support precompilation, includes "wx.h".
  22 #include "wx/wxprec.h"
  23
  24 #if wxUSE_THREADS
  25
  26 #include <stdio.h>
  27
  28 #include "wx/app.h"
  29 #include "wx/module.h"
  30 #include "wx/intl.h"
  31 #include "wx/utils.h"
  32 #include "wx/log.h"
  33 #include "wx/thread.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 wxWindows 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(
 112   wxMutexType                       WXUNUSED(eMutexType)
 113 )
 114 {
 115     APIRET                          ulrc;
 116
 117     ulrc = ::DosCreateMutexSem(NULL, &m_vMutex, 0L, FALSE);
 118     if (ulrc != 0)
 119     {
 120         wxLogSysError(_("Can not create mutex."));
 121         m_vMutex = NULL;
 122     }
 123 }
 124
 125 wxMutexInternal::~wxMutexInternal()
 126 {
 127     if (m_vMutex)
 128     {
 129         if (::DosCloseMutexSem(m_vMutex))
 130             wxLogLastError(_T("DosCloseMutexSem(mutex)"));
 131     }
 132 }
 133
 134 wxMutexError wxMutexInternal::LockTimeout(ULONG ulMilliseconds)
 135 {
 136     APIRET                          ulrc;
 137
 138     ulrc = ::DosRequestMutexSem(m_vMutex, ulMilliseconds);
 139
 140     switch (ulrc)
 141     {
 142         case ERROR_TIMEOUT:
 143         case ERROR_TOO_MANY_SEM_REQUESTS:
 144             return wxMUTEX_BUSY;
 145
 146         case NO_ERROR:
 147             // ok
 148             break;
 149
 150         case ERROR_INVALID_HANDLE:
 151         case ERROR_INTERRUPT:
 152         case ERROR_SEM_OWNER_DIED:
 153             wxLogSysError(_("Couldn't acquire a mutex lock"));
 154             return wxMUTEX_MISC_ERROR;
 155
 156         default:
 157             wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock"));
 158             return wxMUTEX_MISC_ERROR;
 159      }
 160     return wxMUTEX_NO_ERROR;
 161 }
 162
 163 wxMutexError wxMutexInternal::Unlock()
 164 {
 165     APIRET                          ulrc;
 166
 167     ulrc = ::DosReleaseMutexSem(m_vMutex);
 168     if (ulrc != 0)
 169     {
 170         wxLogSysError(_("Couldn't release a mutex"));
 171         return wxMUTEX_MISC_ERROR;
 172     }
 173     return wxMUTEX_NO_ERROR;
 174 }
 175
 176 // --------------------------------------------------------------------------
 177 // wxSemaphore
 178 // --------------------------------------------------------------------------
 179
 180 // a trivial wrapper around OS2 event semaphore
 181 class wxSemaphoreInternal
 182 {
 183 public:
 184     wxSemaphoreInternal(int initialcount, int maxcount);
 185     ~wxSemaphoreInternal();
 186
 187     bool IsOk() const { return m_vEvent != NULL; }
 188
 189     wxSemaError Wait() { return WaitTimeout(SEM_INDEFINITE_WAIT); }
 190     wxSemaError TryWait() { return WaitTimeout(SEM_IMMEDIATE_RETURN); }
 191     wxSemaError WaitTimeout(unsigned long milliseconds);
 192
 193     wxSemaError Post();
 194
 195 private:
 196     HEV m_vEvent;
 197     HMTX m_vMutex;
 198     int m_count;
 199     int m_maxcount;
 200 };
 201
 202 wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount)
 203 {
 204     APIRET ulrc;
 205     if ( maxcount == 0 )
 206     {
 207         // make it practically infinite
 208         maxcount = INT_MAX;
 209     }
 210
 211     m_count = initialcount;
 212     m_maxcount = maxcount;
 213     ulrc = ::DosCreateMutexSem(NULL, &m_vMutex, 0L, FALSE);
 214     if (ulrc != 0)
 215     {
 216         wxLogLastError(_T("DosCreateMutexSem()"));
 217         m_vMutex = NULL;
 218         m_vEvent = NULL;
 219         return;
 220     }
 221     ulrc = ::DosCreateEventSem(NULL, &m_vEvent, 0L, FALSE);
 222     if ( ulrc != 0)
 223     {
 224         wxLogLastError(_T("DosCreateEventSem()"));
 225         ::DosCloseMutexSem(m_vMutex);
 226         m_vMutex = NULL;
 227         m_vEvent = NULL;
 228     }
 229     if (initialcount)
 230         ::DosPostEventSem(m_vEvent);
 231 }
 232
 233 wxSemaphoreInternal::~wxSemaphoreInternal()
 234 {
 235     if ( m_vEvent )
 236     {
 237         if ( ::DosCloseEventSem(m_vEvent) )
 238         {
 239             wxLogLastError(_T("DosCloseEventSem(semaphore)"));
 240         }
 241         if ( ::DosCloseMutexSem(m_vMutex) )
 242         {
 243             wxLogLastError(_T("DosCloseMutexSem(semaphore)"));
 244         }
 245         else
 246             m_vEvent = NULL;
 247     }
 248 }
 249
 250 wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long ulMilliseconds)
 251 {
 252     APIRET ulrc;
 253     do {
 254         ulrc = ::DosWaitEventSem(m_vEvent, ulMilliseconds );
 255         switch ( ulrc )
 256         {
 257             case NO_ERROR:
 258                 break;
 259
 260             case ERROR_TIMEOUT:
 261                 if (ulMilliseconds == SEM_IMMEDIATE_RETURN)
 262                     return wxSEMA_BUSY;
 263                 else
 264                     return wxSEMA_TIMEOUT;
 265
 266             default:
 267                 wxLogLastError(_T("DosWaitEventSem(semaphore)"));
 268                 return wxSEMA_MISC_ERROR;
 269         }
 270         ulrc = :: DosRequestMutexSem(m_vMutex, ulMilliseconds);
 271         switch ( ulrc )
 272         {
 273             case NO_ERROR:
 274                 // ok
 275                 break;
 276
 277             case ERROR_TIMEOUT:
 278             case ERROR_TOO_MANY_SEM_REQUESTS:
 279                 if (ulMilliseconds == SEM_IMMEDIATE_RETURN)
 280                     return wxSEMA_BUSY;
 281                 else
 282                     return wxSEMA_TIMEOUT;
 283
 284             default:
 285                 wxFAIL_MSG(wxT("DosRequestMutexSem(mutex)"));
 286                 return wxSEMA_MISC_ERROR;
 287         }
 288         bool OK = false;
 289         if (m_count > 0)
 290         {
 291             m_count--;
 292             OK = true;
 293         }
 294         else
 295         {
 296             ULONG ulPostCount;
 297             ::DosResetEventSem(m_vEvent, &ulPostCount);
 298         }
 299         ::DosReleaseMutexSem(m_vMutex);
 300         if (OK)
 301             return wxSEMA_NO_ERROR;
 302     } while (ulMilliseconds == SEM_INDEFINITE_WAIT);
 303
 304     if (ulMilliseconds == SEM_IMMEDIATE_RETURN)
 305         return wxSEMA_BUSY;
 306     return wxSEMA_TIMEOUT;
 307 }
 308
 309 wxSemaError wxSemaphoreInternal::Post()
 310 {
 311     APIRET ulrc;
 312     ulrc = ::DosRequestMutexSem(m_vMutex, SEM_INDEFINITE_WAIT);
 313     if (ulrc != NO_ERROR)
 314         return wxSEMA_MISC_ERROR;
 315     bool OK = false;
 316     if (m_count < m_maxcount)
 317     {
 318         m_count++;
 319         ulrc = ::DosPostEventSem(m_vEvent);
 320         OK = true;
 321     }
 322     ::DosReleaseMutexSem(m_vMutex);
 323     if (!OK)
 324         return wxSEMA_OVERFLOW;
 325     if ( ulrc != NO_ERROR && ulrc != ERROR_ALREADY_POSTED )
 326     {
 327         wxLogLastError(_T("DosPostEventSem(semaphore)"));
 328
 329         return wxSEMA_MISC_ERROR;
 330     }
 331
 332     return wxSEMA_NO_ERROR;
 333 }
 334
 335 // ----------------------------------------------------------------------------
 336 // wxThread implementation
 337 // ----------------------------------------------------------------------------
 338
 339 // wxThreadInternal class
 340 // ----------------------
 341
 342 class wxThreadInternal
 343 {
 344 public:
 345     inline wxThreadInternal()
 346     {
 347         m_hThread = 0;
 348         m_eState = STATE_NEW;
 349         m_nPriority = WXTHREAD_DEFAULT_PRIORITY;
 350     }
 351
 352     ~wxThreadInternal()
 353     {
 354         m_hThread = 0;
 355     }
 356
 357     // create a new (suspended) thread (for the given thread object)
 358     bool Create( wxThread*    pThread
 359                 ,unsigned int uStackSize
 360                );
 361
 362     // suspend/resume/terminate
 363     bool Suspend();
 364     bool Resume();
 365     inline void Cancel() { m_eState = STATE_CANCELED; }
 366
 367     // thread state
 368     inline void SetState(wxThreadState eState) { m_eState = eState; }
 369     inline wxThreadState GetState() const { return m_eState; }
 370
 371     // thread priority
 372     void                SetPriority(unsigned int nPriority);
 373     inline unsigned int GetPriority() const { return m_nPriority; }
 374
 375     // thread handle and id
 376     inline TID GetHandle() const { return m_hThread; }
 377     TID  GetId() const { return m_hThread; }
 378
 379     // thread function
 380     static void OS2ThreadStart(void* pParam);
 381
 382 private:
 383     // Threads in OS/2 have only an ID, so m_hThread is both it's handle and ID
 384     // PM also has no real Tls mechanism to index pointers by so we'll just
 385     // keep track of the wxWindows parent object here.
 386     TID                             m_hThread;    // handle and ID of the thread
 387     wxThreadState                   m_eState;     // state, see wxThreadState enum
 388     unsigned int                    m_nPriority;  // thread priority in "wx" units
 389 };
 390
 391 void wxThreadInternal::OS2ThreadStart(
 392   void * pParam
 393 )
 394 {
 395     DWORD                           dwRet;
 396     bool bWasCancelled;
 397
 398     wxThread *pThread = (wxThread *)pParam;
 399
 400     // first of all, wait for the thread to be started.
 401     pThread->m_critsect.Enter();
 402     pThread->m_critsect.Leave();
 403     // Now check whether we hadn't been cancelled already and don't
 404     // start the user code at all in this case.
 405     if ( pThread->m_internal->GetState() == STATE_EXITED )
 406     {
 407         dwRet = (DWORD)-1;
 408         bWasCancelled = TRUE;
 409     }
 410     else // do run thread
 411     {
 412         dwRet = (DWORD)pThread->Entry();
 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 wxWindows 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(
 471   wxThread*                         pThread
 472 , unsigned int                      uStackSize
 473 )
 474 {
 475     int                          tid;
 476
 477     if (!uStackSize)
 478       uStackSize = 131072;
 479     pThread->m_critsect.Enter();
 480     tid = _beginthread(wxThreadInternal::OS2ThreadStart,
 481                              NULL, uStackSize, pThread);
 482     if(tid == -1)
 483     {
 484         wxLogSysError(_("Can't create thread"));
 485
 486         return FALSE;
 487     }
 488     m_hThread = tid;
 489     if (m_nPriority != WXTHREAD_DEFAULT_PRIORITY)
 490     {
 491         SetPriority(m_nPriority);
 492     }
 493
 494     return(TRUE);
 495 }
 496
 497 bool wxThreadInternal::Suspend()
 498 {
 499     ULONG                           ulrc = ::DosSuspendThread(m_hThread);
 500
 501     if (ulrc != 0)
 502     {
 503         wxLogSysError(_("Can not suspend thread %lu"), m_hThread);
 504         return FALSE;
 505     }
 506     m_eState = STATE_PAUSED;
 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     return FALSE;
 550 }
 551
 552 #ifdef Yield
 553     #undef Yield
 554 #endif
 555
 556 void wxThread::Yield()
 557 {
 558     ::DosSleep(0);
 559 }
 560
 561 void wxThread::Sleep(
 562   unsigned long                     ulMilliseconds
 563 )
 564 {
 565     ::DosSleep(ulMilliseconds);
 566 }
 567
 568 int wxThread::GetCPUCount()
 569 {
 570     ULONG CPUCount;
 571     APIRET ulrc;
 572     ulrc = ::DosQuerySysInfo(26, 26, (void *)&CPUCount, sizeof(ULONG));
 573     // QSV_NUMPROCESSORS(26) is typically not defined in header files
 574
 575     if (ulrc != 0)
 576         CPUCount = 1;
 577
 578     return CPUCount;
 579 }
 580
 581 unsigned long wxThread::GetCurrentId()
 582 {
 583     PTIB                            ptib;
 584     PPIB                            ppib;
 585
 586     ::DosGetInfoBlocks(&ptib, &ppib);
 587     return (unsigned long) ptib->tib_ptib2->tib2_ultid;
 588 }
 589
 590 bool wxThread::SetConcurrency(size_t level)
 591 {
 592     wxASSERT_MSG( IsMain(), _T("should only be called from the main thread") );
 593
 594     // ok only for the default one
 595     if ( level == 0 )
 596         return 0;
 597
 598     // Don't know how to realize this on OS/2.
 599     return level == 1;
 600 }
 601
 602 // ctor and dtor
 603 // -------------
 604
 605 wxThread::wxThread(wxThreadKind kind)
 606 {
 607     m_internal = new wxThreadInternal();
 608
 609     m_isDetached = kind == wxTHREAD_DETACHED;
 610 }
 611
 612 wxThread::~wxThread()
 613 {
 614     delete m_internal;
 615 }
 616
 617 // create/start thread
 618 // -------------------
 619
 620 wxThreadError wxThread::Create(
 621   unsigned int                      uStackSize
 622 )
 623 {
 624     wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect);
 625
 626     if ( !m_internal->Create(this, uStackSize) )
 627         return wxTHREAD_NO_RESOURCE;
 628
 629     return wxTHREAD_NO_ERROR;
 630 }
 631
 632 wxThreadError wxThread::Run()
 633 {
 634     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 635
 636     if ( m_internal->GetState() != STATE_NEW )
 637     {
 638         // actually, it may be almost any state at all, not only STATE_RUNNING
 639         return wxTHREAD_RUNNING;
 640     }
 641     return Resume();
 642 }
 643
 644 // suspend/resume thread
 645 // ---------------------
 646
 647 wxThreadError wxThread::Pause()
 648 {
 649     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 650
 651     return m_internal->Suspend() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR;
 652 }
 653
 654 wxThreadError wxThread::Resume()
 655 {
 656     if (m_internal->GetState() == STATE_NEW)
 657     {
 658         m_internal->SetState(STATE_RUNNING);
 659         m_critsect.Leave();
 660         return wxTHREAD_NO_ERROR;
 661     }
 662
 663     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 664
 665     return m_internal->Resume() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR;
 666 }
 667
 668 // stopping thread
 669 // ---------------
 670
 671 wxThread::ExitCode wxThread::Wait()
 672 {
 673     // although under Windows we can wait for any thread, it's an error to
 674     // wait for a detached one in wxWin API
 675     wxCHECK_MSG( !IsDetached(), (ExitCode)-1,
 676                  _T("can't wait for detached thread") );
 677     ExitCode rc = (ExitCode)-1;
 678     (void)Delete(&rc);
 679     return(rc);
 680 }
 681
 682 wxThreadError wxThread::Delete(ExitCode *pRc)
 683 {
 684     ExitCode rc = 0;
 685
 686     // Delete() is always safe to call, so consider all possible states
 687
 688     // we might need to resume the thread, but we might also not need to cancel
 689     // it if it doesn't run yet
 690     bool shouldResume = FALSE,
 691          shouldCancel = TRUE,
 692          isRunning = FALSE;
 693
 694     // check if the thread already started to run
 695     {
 696         wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 697
 698         if ( m_internal->GetState() == STATE_NEW )
 699         {
 700             // WinThreadStart() will see it and terminate immediately, no need
 701             // to cancel the thread - but we still need to resume it to let it
 702             // run
 703             m_internal->SetState(STATE_EXITED);
 704
 705             Resume();   // it knows about STATE_EXITED special case
 706
 707             shouldCancel = FALSE;
 708             isRunning = TRUE;
 709
 710             // shouldResume is correctly set to FALSE here
 711         }
 712         else
 713         {
 714             shouldResume = IsPaused();
 715         }
 716     }
 717
 718     // resume the thread if it is paused
 719     if ( shouldResume )
 720         Resume();
 721
 722     TID                             hThread = m_internal->GetHandle();
 723
 724     if ( isRunning || IsRunning())
 725     {
 726         if (IsMain())
 727         {
 728             // set flag for wxIsWaitingForThread()
 729             gs_bWaitingForThread = TRUE;
 730         }
 731
 732         // ask the thread to terminate
 733         if ( shouldCancel )
 734         {
 735             wxCriticalSectionLocker lock(m_critsect);
 736
 737             m_internal->Cancel();
 738         }
 739
 740 #if wxUSE_GUI
 741         // we can't just wait for the thread to terminate because it might be
 742         // calling some GUI functions and so it will never terminate before we
 743         // process the Windows messages that result from these functions
 744         DWORD result = 0;       // suppress warnings from broken compilers
 745         do
 746         {
 747             if ( IsMain() )
 748             {
 749                 // give the thread we're waiting for chance to do the GUI call
 750                 // it might be in
 751                 if ( (gs_nWaitingForGui > 0) && wxGuiOwnedByMainThread() )
 752                 {
 753                     wxMutexGuiLeave();
 754                 }
 755             }
 756
 757             result = ::DosWaitThread(&hThread, DCWW_NOWAIT);
 758             // FIXME: We ought to have a message processing loop here!!
 759
 760             switch ( result )
 761             {
 762                 case ERROR_INTERRUPT:
 763                 case ERROR_THREAD_NOT_TERMINATED:
 764                     break;
 765                 case ERROR_INVALID_THREADID:
 766                 case NO_ERROR:
 767                     // thread we're waiting for just terminated
 768                     // or even does not exist any more.
 769                     result = NO_ERROR;
 770                     break;
 771                 default:
 772                     wxFAIL_MSG(wxT("unexpected result of DosWaitThread"));
 773             }
 774             if ( IsMain() )
 775             {
 776                 // event processing - needed if we are the main thread
 777                 // to give other threads a chance to do remaining GUI
 778                 // processing and terminate cleanly.
 779                 wxTheApp->HandleSockets();
 780                 if (wxTheApp->Pending())
 781                   if ( !wxTheApp->DoMessage() )
 782                   {
 783                       // WM_QUIT received: kill the thread
 784                       Kill();
 785
 786                       return wxTHREAD_KILLED;
 787                   }
 788                   else
 789                     wxUsleep(10);
 790             }
 791             else
 792                 wxUsleep(10);
 793         } while ( result != NO_ERROR );
 794 #else // !wxUSE_GUI
 795         // simply wait for the thread to terminate
 796         //
 797         // OTOH, even console apps create windows (in wxExecute, for WinSock
 798         // &c), so may be use MsgWaitForMultipleObject() too here?
 799         if ( ::DosWaitThread(&hThread, DCWW_WAIT) != NO_ERROR )
 800         {
 801             wxFAIL_MSG(wxT("unexpected result of DosWaitThread"));
 802         }
 803 #endif // wxUSE_GUI/!wxUSE_GUI
 804
 805         if ( IsMain() )
 806         {
 807             gs_bWaitingForThread = FALSE;
 808         }
 809     }
 810
 811 #if 0
 812     // although the thread might be already in the EXITED state it might not
 813     // have terminated yet and so we are not sure that it has actually
 814     // terminated if the "if" above hadn't been taken
 815     do
 816     {
 817         if ( !::GetExitCodeThread(hThread, (LPDWORD)&rc) )
 818         {
 819             wxLogLastError(wxT("GetExitCodeThread"));
 820
 821             rc = (ExitCode)-1;
 822         }
 823     } while ( (DWORD)rc == STILL_ACTIVE );
 824 #endif
 825
 826     if ( IsDetached() )
 827     {
 828         // if the thread exits normally, this is done in WinThreadStart, but in
 829         // this case it would have been too early because
 830         // MsgWaitForMultipleObject() would fail if the thread handle was
 831         // closed while we were waiting on it, so we must do it here
 832         delete this;
 833     }
 834
 835     if ( pRc )
 836         *pRc = rc;
 837
 838     return rc == (ExitCode)-1 ? wxTHREAD_MISC_ERROR : wxTHREAD_NO_ERROR;
 839 }
 840
 841 wxThreadError wxThread::Kill()
 842 {
 843     if (!IsRunning())
 844         return wxTHREAD_NOT_RUNNING;
 845
 846     ::DosKillThread(m_internal->GetHandle());
 847     if (IsDetached())
 848     {
 849         delete this;
 850     }
 851     return wxTHREAD_NO_ERROR;
 852 }
 853
 854 void wxThread::Exit(
 855   ExitCode                          pStatus
 856 )
 857 {
 858     delete this;
 859     _endthread();
 860     wxFAIL_MSG(wxT("Couldn't return from DosExit()!"));
 861 }
 862
 863 void wxThread::SetPriority(
 864   unsigned int                      nPrio
 865 )
 866 {
 867     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 868
 869     m_internal->SetPriority(nPrio);
 870 }
 871
 872 unsigned int wxThread::GetPriority() const
 873 {
 874     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 875
 876     return m_internal->GetPriority();
 877 }
 878
 879 unsigned long wxThread::GetId() const
 880 {
 881     wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast
 882
 883     return (unsigned long)m_internal->GetId();
 884 }
 885
 886 bool wxThread::IsRunning() const
 887 {
 888     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 889
 890     return(m_internal->GetState() == STATE_RUNNING);
 891 }
 892
 893 bool wxThread::IsAlive() const
 894 {
 895     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 896
 897     return (m_internal->GetState() == STATE_RUNNING) ||
 898            (m_internal->GetState() == STATE_PAUSED);
 899 }
 900
 901 bool wxThread::IsPaused() const
 902 {
 903     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 904
 905     return (m_internal->GetState() == STATE_PAUSED);
 906 }
 907
 908 bool wxThread::TestDestroy()
 909 {
 910     wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
 911
 912     return m_internal->GetState() == STATE_CANCELED;
 913 }
 914
 915 // ----------------------------------------------------------------------------
 916 // Automatic initialization for thread module
 917 // ----------------------------------------------------------------------------
 918
 919 class wxThreadModule : public wxModule
 920 {
 921 public:
 922     virtual bool OnInit();
 923     virtual void OnExit();
 924
 925 private:
 926     DECLARE_DYNAMIC_CLASS(wxThreadModule)
 927 };
 928
 929 IMPLEMENT_DYNAMIC_CLASS(wxThreadModule, wxModule)
 930
 931 bool wxThreadModule::OnInit()
 932 {
 933     gs_pCritsectWaitingForGui = new wxCriticalSection();
 934
 935     gs_pCritsectGui = new wxCriticalSection();
 936     gs_pCritsectGui->Enter();
 937
 938     PTIB                            ptib;
 939     PPIB                            ppib;
 940
 941     ::DosGetInfoBlocks(&ptib, &ppib);
 942
 943     s_ulIdMainThread = ptib->tib_ptib2->tib2_ultid;
 944     return TRUE;
 945 }
 946
 947 void wxThreadModule::OnExit()
 948 {
 949     if (gs_pCritsectGui)
 950     {
 951         gs_pCritsectGui->Leave();
 952 #if (!(defined(__VISAGECPP__) && (__IBMCPP__ < 400 || __IBMC__ < 400 )))
 953         delete gs_pCritsectGui;
 954 #endif
 955         gs_pCritsectGui = NULL;
 956     }
 957
 958 #if (!(defined(__VISAGECPP__) && (__IBMCPP__ < 400 || __IBMC__ < 400 )))
 959     wxDELETE(gs_pCritsectWaitingForGui);
 960 #endif
 961 }
 962
 963 // ----------------------------------------------------------------------------
 964 // Helper functions
 965 // ----------------------------------------------------------------------------
 966
 967 // wake up the main thread if it's in ::GetMessage()
 968 void WXDLLEXPORT wxWakeUpMainThread()
 969 {
 970 #if 0
 971     if ( !::WinPostQueueMsg(wxTheApp->m_hMq, WM_NULL, 0, 0) )
 972     {
 973         // should never happen
 974         wxLogLastError(wxT("WinPostMessage(WM_NULL)"));
 975     }
 976 #endif
 977 }
 978
 979 void WXDLLEXPORT wxMutexGuiEnter()
 980 {
 981     // this would dead lock everything...
 982     wxASSERT_MSG( !wxThread::IsMain(),
 983                   wxT("main thread doesn't want to block in wxMutexGuiEnter()!") );
 984
 985     // the order in which we enter the critical sections here is crucial!!
 986
 987     // set the flag telling to the main thread that we want to do some GUI
 988     {
 989         wxCriticalSectionLocker enter(*gs_pCritsectWaitingForGui);
 990
 991         gs_nWaitingForGui++;
 992     }
 993
 994     wxWakeUpMainThread();
 995
 996     // now we may block here because the main thread will soon let us in
 997     // (during the next iteration of OnIdle())
 998     gs_pCritsectGui->Enter();
 999 }
1000
1001 void WXDLLEXPORT wxMutexGuiLeave()
1002 {
1003     wxCriticalSectionLocker enter(*gs_pCritsectWaitingForGui);
1004
1005     if ( wxThread::IsMain() )
1006     {
1007         gs_bGuiOwnedByMainThread = FALSE;
1008     }
1009     else
1010     {
1011         // decrement the number of waiters now
1012         wxASSERT_MSG(gs_nWaitingForGui > 0,
1013                       wxT("calling wxMutexGuiLeave() without entering it first?") );
1014
1015         gs_nWaitingForGui--;
1016
1017         wxWakeUpMainThread();
1018     }
1019
1020     gs_pCritsectGui->Leave();
1021 }
1022
1023 void WXDLLEXPORT wxMutexGuiLeaveOrEnter()
1024 {
1025     wxASSERT_MSG( wxThread::IsMain(),
1026                   wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") );
1027
1028     wxCriticalSectionLocker enter(*gs_pCritsectWaitingForGui);
1029
1030     if (gs_nWaitingForGui == 0)
1031     {
1032         // no threads are waiting for GUI - so we may acquire the lock without
1033         // any danger (but only if we don't already have it)
1034         if (!wxGuiOwnedByMainThread())
1035         {
1036             gs_pCritsectGui->Enter();
1037
1038             gs_bGuiOwnedByMainThread = TRUE;
1039         }
1040         //else: already have it, nothing to do
1041     }
1042     else
1043     {
1044         // some threads are waiting, release the GUI lock if we have it
1045         if (wxGuiOwnedByMainThread())
1046         {
1047             wxMutexGuiLeave();
1048         }
1049         //else: some other worker thread is doing GUI
1050     }
1051 }
1052
1053 bool WXDLLEXPORT wxGuiOwnedByMainThread()
1054 {
1055     return gs_bGuiOwnedByMainThread;
1056 }
1057
1058 bool WXDLLEXPORT wxIsWaitingForThread()
1059 {
1060     return gs_bWaitingForThread;
1061 }
1062
1063 // ----------------------------------------------------------------------------
1064 // include common implementation code
1065 // ----------------------------------------------------------------------------
1066
1067 #include "wx/thrimpl.cpp"
1068
1069 #endif
1070   // wxUSE_THREADS