src/unix/threadpsx.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        threadpsx.cpp
   3 // Purpose:     wxThread (Posix) Implementation
   4 // Author:      Original from Wolfram Gloger/Guilhem Lavaux
   5 // Modified by:
   6 // Created:     04/22/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Wolfram Gloger (1996, 1997)
   9 //                  Guilhem Lavaux (1998)
  10 //                  Vadim Zeitlin (1999)
  11 //                  Robert Roebling (1999)
  12 // Licence:     wxWindows licence
  13 /////////////////////////////////////////////////////////////////////////////
  14
  15 // ============================================================================
  16 // declaration
  17 // ============================================================================
  18
  19 // ----------------------------------------------------------------------------
  20 // headers
  21 // ----------------------------------------------------------------------------
  22
  23 #ifdef __GNUG__
  24     #pragma implementation "thread.h"
  25 #endif
  26
  27 // With simple makefiles, we must ignore the file body if not using
  28 // threads.
  29 #include "wx/setup.h"
  30
  31 #if wxUSE_THREADS
  32
  33 #include "wx/thread.h"
  34 #include "wx/module.h"
  35 #include "wx/utils.h"
  36 #include "wx/log.h"
  37 #include "wx/intl.h"
  38 #include "wx/dynarray.h"
  39
  40 #include <stdio.h>
  41 #include <unistd.h>
  42 #include <pthread.h>
  43 #include <errno.h>
  44 #include <time.h>
  45
  46 #if HAVE_SCHED_H
  47     #include <sched.h>
  48 #endif
  49
  50 // ----------------------------------------------------------------------------
  51 // constants
  52 // ----------------------------------------------------------------------------
  53
  54 // the possible states of the thread and transitions from them
  55 enum wxThreadState
  56 {
  57     STATE_NEW,          // didn't start execution yet (=> RUNNING)
  58     STATE_RUNNING,      // running (=> PAUSED or EXITED)
  59     STATE_PAUSED,       // suspended (=> RUNNING or EXITED)
  60     STATE_EXITED        // thread doesn't exist any more
  61 };
  62
  63 // ----------------------------------------------------------------------------
  64 // types
  65 // ----------------------------------------------------------------------------
  66
  67 WX_DEFINE_ARRAY(wxThread *, wxArrayThread);
  68
  69 // -----------------------------------------------------------------------------
  70 // global data
  71 // -----------------------------------------------------------------------------
  72
  73 // we keep the list of all threads created by the application to be able to
  74 // terminate them on exit if there are some left - otherwise the process would
  75 // be left in memory
  76 static wxArrayThread gs_allThreads;
  77
  78 // the id of the main thread
  79 static pthread_t gs_tidMain;
  80
  81 // the key for the pointer to the associated wxThread object
  82 static pthread_key_t gs_keySelf;
  83
  84 // this mutex must be acquired before any call to a GUI function
  85 static wxMutex *gs_mutexGui;
  86
  87 // ============================================================================
  88 // implementation
  89 // ============================================================================
  90
  91 //--------------------------------------------------------------------
  92 // wxMutex (Posix implementation)
  93 //--------------------------------------------------------------------
  94
  95 class wxMutexInternal
  96 {
  97 public:
  98     pthread_mutex_t p_mutex;
  99 };
 100
 101 wxMutex::wxMutex()
 102 {
 103     p_internal = new wxMutexInternal;
 104
 105     pthread_mutex_init( &(p_internal->p_mutex), (const pthread_mutexattr_t*) NULL );
 106     m_locked = 0;
 107 }
 108
 109 wxMutex::~wxMutex()
 110 {
 111     if (m_locked > 0)
 112         wxLogDebug(T("Freeing a locked mutex (%d locks)"), m_locked);
 113
 114     pthread_mutex_destroy( &(p_internal->p_mutex) );
 115     delete p_internal;
 116 }
 117
 118 wxMutexError wxMutex::Lock()
 119 {
 120     int err = pthread_mutex_lock( &(p_internal->p_mutex) );
 121     if (err == EDEADLK)
 122     {
 123         wxLogDebug(T("Locking this mutex would lead to deadlock!"));
 124
 125         return wxMUTEX_DEAD_LOCK;
 126     }
 127
 128     m_locked++;
 129
 130     return wxMUTEX_NO_ERROR;
 131 }
 132
 133 wxMutexError wxMutex::TryLock()
 134 {
 135     if (m_locked)
 136     {
 137         return wxMUTEX_BUSY;
 138     }
 139
 140     int err = pthread_mutex_trylock( &(p_internal->p_mutex) );
 141     switch (err)
 142     {
 143         case EBUSY: return wxMUTEX_BUSY;
 144     }
 145
 146     m_locked++;
 147
 148     return wxMUTEX_NO_ERROR;
 149 }
 150
 151 wxMutexError wxMutex::Unlock()
 152 {
 153     if (m_locked > 0)
 154     {
 155         m_locked--;
 156     }
 157     else
 158     {
 159         wxLogDebug(T("Unlocking not locked mutex."));
 160
 161         return wxMUTEX_UNLOCKED;
 162     }
 163
 164     pthread_mutex_unlock( &(p_internal->p_mutex) );
 165
 166     return wxMUTEX_NO_ERROR;
 167 }
 168
 169 //--------------------------------------------------------------------
 170 // wxCondition (Posix implementation)
 171 //--------------------------------------------------------------------
 172
 173 class wxConditionInternal
 174 {
 175 public:
 176   pthread_cond_t p_condition;
 177 };
 178
 179 wxCondition::wxCondition()
 180 {
 181     p_internal = new wxConditionInternal;
 182     pthread_cond_init( &(p_internal->p_condition), (const pthread_condattr_t *) NULL );
 183 }
 184
 185 wxCondition::~wxCondition()
 186 {
 187     pthread_cond_destroy( &(p_internal->p_condition) );
 188
 189     delete p_internal;
 190 }
 191
 192 void wxCondition::Wait(wxMutex& mutex)
 193 {
 194     pthread_cond_wait( &(p_internal->p_condition), &(mutex.p_internal->p_mutex) );
 195 }
 196
 197 bool wxCondition::Wait(wxMutex& mutex, unsigned long sec, unsigned long nsec)
 198 {
 199     struct timespec tspec;
 200
 201     tspec.tv_sec = time(0L)+sec;
 202     tspec.tv_nsec = nsec;
 203     return (pthread_cond_timedwait(&(p_internal->p_condition), &(mutex.p_internal->p_mutex), &tspec) != ETIMEDOUT);
 204 }
 205
 206 void wxCondition::Signal()
 207 {
 208     pthread_cond_signal( &(p_internal->p_condition) );
 209 }
 210
 211 void wxCondition::Broadcast()
 212 {
 213     pthread_cond_broadcast( &(p_internal->p_condition) );
 214 }
 215
 216 //--------------------------------------------------------------------
 217 // wxThread (Posix implementation)
 218 //--------------------------------------------------------------------
 219
 220 class wxThreadInternal
 221 {
 222 public:
 223     wxThreadInternal();
 224     ~wxThreadInternal();
 225
 226     // thread entry function
 227     static void *PthreadStart(void *ptr);
 228
 229 #if HAVE_THREAD_CLEANUP_FUNCTIONS
 230     // thread exit function
 231     static void PthreadCleanup(void *ptr);
 232 #endif
 233
 234     // thread actions
 235         // start the thread
 236     wxThreadError Run();
 237         // ask the thread to terminate
 238     void Wait();
 239         // wake up threads waiting for our termination
 240     void SignalExit();
 241         // go to sleep until Resume() is called
 242     void Pause();
 243         // resume the thread
 244     void Resume();
 245
 246     // accessors
 247         // priority
 248     int GetPriority() const { return m_prio; }
 249     void SetPriority(int prio) { m_prio = prio; }
 250         // state
 251     wxThreadState GetState() const { return m_state; }
 252     void SetState(wxThreadState state) { m_state = state; }
 253         // id
 254     pthread_t GetId() const { return m_threadId; }
 255     pthread_t *GetIdPtr() { return &m_threadId; }
 256         // "cancelled" flag
 257     void SetCancelFlag() { m_cancelled = TRUE; }
 258     bool WasCancelled() const { return m_cancelled; }
 259
 260 private:
 261     pthread_t     m_threadId;   // id of the thread
 262     wxThreadState m_state;      // see wxThreadState enum
 263     int           m_prio;       // in wxWindows units: from 0 to 100
 264
 265     // set when the thread should terminate
 266     bool m_cancelled;
 267
 268     // this (mutex, cond) pair is used to synchronize the main thread and this
 269     // thread in several situations:
 270     //  1. The thread function blocks until condition is signaled by Run() when
 271     //     it's initially created - this allows thread creation in "suspended"
 272     //     state
 273     //  2. The Delete() function blocks until the condition is signaled when the
 274     //     thread exits.
 275     // GL: On Linux, this may fail because we can have a deadlock in either
 276     //     SignalExit() or Wait(): so we add m_end_mutex for the finalization.
 277     wxMutex     m_mutex, m_end_mutex;
 278     wxCondition m_cond;
 279
 280     // another (mutex, cond) pair for Pause()/Resume() usage
 281     //
 282     // VZ: it's possible that we might reuse the mutex and condition from above
 283     //     for this too, but as I'm not at all sure that it won't create subtle
 284     //     problems with race conditions between, say, Pause() and Delete() I
 285     //     prefer this may be a bit less efficient but much safer solution
 286     wxMutex     m_mutexSuspend;
 287     wxCondition m_condSuspend;
 288 };
 289
 290 void *wxThreadInternal::PthreadStart(void *ptr)
 291 {
 292     wxThread *thread = (wxThread *)ptr;
 293     wxThreadInternal *pthread = thread->p_internal;
 294     void *status;
 295
 296     int rc = pthread_setspecific(gs_keySelf, thread);
 297     if ( rc != 0 )
 298     {
 299         wxLogSysError(rc, _("Cannot start thread: error writing TLS"));
 300
 301         return (void *)-1;
 302     }
 303 #if HAVE_THREAD_CLEANUP_FUNCTIONS
 304     // Install the cleanup handler.
 305     pthread_cleanup_push(wxThreadInternal::PthreadCleanup, ptr);
 306 #endif
 307
 308     // wait for the condition to be signaled from Run()
 309     // mutex state: currently locked by the thread which created us
 310     pthread->m_cond.Wait(pthread->m_mutex);
 311     // mutex state: locked again on exit of Wait()
 312
 313     // call the main entry
 314     status = thread->Entry();
 315
 316 #if HAVE_THREAD_CLEANUP_FUNCTIONS
 317     pthread_cleanup_pop(FALSE);
 318 #endif
 319
 320     // terminate the thread
 321     thread->Exit(status);
 322
 323     wxFAIL_MSG(T("wxThread::Exit() can't return."));
 324
 325     return NULL;
 326 }
 327
 328 #if HAVE_THREAD_CLEANUP_FUNCTIONS
 329 // Only called when the thread is explicitely killed.
 330
 331 void wxThreadInternal::PthreadCleanup(void *ptr)
 332 {
 333     wxThread *thread = (wxThread *) ptr;
 334
 335     // The thread is already considered as finished.
 336     if (thread->p_internal->GetState() == STATE_EXITED)
 337       return;
 338
 339     // first call user-level clean up code
 340     thread->OnExit();
 341
 342     // next wake up the threads waiting for us (OTOH, this function won't retur
 343     // until someone waited for us!)
 344     thread->p_internal->SetState(STATE_EXITED);
 345
 346     thread->p_internal->SignalExit();
 347 }
 348 #endif
 349
 350 wxThreadInternal::wxThreadInternal()
 351 {
 352     m_state = STATE_NEW;
 353     m_cancelled = FALSE;
 354
 355     // this mutex is locked during almost all thread lifetime - it will only be
 356     // unlocked in the very end
 357     m_mutex.Lock();
 358
 359     // this mutex is used by wxThreadInternal::Wait() and by
 360     // wxThreadInternal::SignalExit(). We don't use m_mutex because of a
 361     // possible deadlock in either Wait() or SignalExit().
 362     m_end_mutex.Lock();
 363
 364     // this mutex is used in Pause()/Resume() and is also locked all the time
 365     // unless the thread is paused
 366     m_mutexSuspend.Lock();
 367 }
 368
 369 wxThreadInternal::~wxThreadInternal()
 370 {
 371     // GL: moved to SignalExit
 372     // m_mutexSuspend.Unlock();
 373
 374     // note that m_mutex will be unlocked by the thread which waits for our
 375     // termination
 376
 377     // In the case, we didn't start the thread, all these mutex are locked:
 378     // we must unlock them.
 379     if (m_mutex.IsLocked())
 380       m_mutex.Unlock();
 381
 382     if (m_end_mutex.IsLocked())
 383       m_end_mutex.Unlock();
 384
 385     if (m_mutexSuspend.IsLocked())
 386       m_mutexSuspend.Unlock();
 387 }
 388
 389 wxThreadError wxThreadInternal::Run()
 390 {
 391     wxCHECK_MSG( GetState() == STATE_NEW, wxTHREAD_RUNNING,
 392                  T("thread may only be started once after successful Create()") );
 393
 394     // the mutex was locked on Create(), so we will be able to lock it again
 395     // only when the thread really starts executing and enters the wait -
 396     // otherwise we might signal the condition before anybody is waiting for it
 397     wxMutexLocker lock(m_mutex);
 398     m_cond.Signal();
 399
 400     m_state = STATE_RUNNING;
 401
 402     return wxTHREAD_NO_ERROR;
 403
 404     // now the mutex is unlocked back - but just to allow Wait() function to
 405     // terminate by relocking it, so the net result is that the worker thread
 406     // starts executing and the mutex is still locked
 407 }
 408
 409 void wxThreadInternal::Wait()
 410 {
 411     wxCHECK_RET( WasCancelled(), T("thread should have been cancelled first") );
 412
 413     // if the thread we're waiting for is waiting for the GUI mutex, we will
 414     // deadlock so make sure we release it temporarily
 415     if ( wxThread::IsMain() )
 416         wxMutexGuiLeave();
 417
 418     // entering Wait() releases the mutex thus allowing SignalExit() to acquire
 419     // it and to signal us its termination
 420     m_cond.Wait(m_end_mutex);
 421
 422     // mutex is still in the locked state - relocked on exit from Wait(), so
 423     // unlock it - we don't need it any more, the thread has already terminated
 424     m_end_mutex.Unlock();
 425
 426     // After that, we wait for the real end of the other thread.
 427     pthread_join(GetId(), NULL);
 428
 429     // reacquire GUI mutex
 430     if ( wxThread::IsMain() )
 431         wxMutexGuiEnter();
 432 }
 433
 434 void wxThreadInternal::SignalExit()
 435 {
 436     // GL: Unlock mutexSuspend here.
 437     m_mutexSuspend.Unlock();
 438
 439     // as mutex is currently locked, this will block until some other thread
 440     // (normally the same which created this one) unlocks it by entering Wait()
 441     m_end_mutex.Lock();
 442
 443     // wake up all the threads waiting for our termination
 444     m_cond.Broadcast();
 445
 446     // after this call mutex will be finally unlocked
 447     m_end_mutex.Unlock();
 448 }
 449
 450 void wxThreadInternal::Pause()
 451 {
 452     // the state is set from the thread which pauses us first, this function
 453     // is called later so the state should have been already set
 454     wxCHECK_RET( m_state == STATE_PAUSED,
 455                  T("thread must first be paused with wxThread::Pause().") );
 456
 457     // don't pause the thread which is being terminated - this would lead to
 458     // deadlock if the thread is paused after Delete() had called Resume() but
 459     // before it had time to call Wait()
 460     if ( WasCancelled() )
 461         return;
 462
 463     // wait until the condition is signaled from Resume()
 464     m_condSuspend.Wait(m_mutexSuspend);
 465 }
 466
 467 void wxThreadInternal::Resume()
 468 {
 469     wxCHECK_RET( m_state == STATE_PAUSED,
 470                  T("can't resume thread which is not suspended.") );
 471
 472     // we will be able to lock this mutex only when Pause() starts waiting
 473     wxMutexLocker lock(m_mutexSuspend);
 474     m_condSuspend.Signal();
 475
 476     SetState(STATE_RUNNING);
 477 }
 478
 479 // -----------------------------------------------------------------------------
 480 // static functions
 481 // -----------------------------------------------------------------------------
 482
 483 wxThread *wxThread::This()
 484 {
 485     return (wxThread *)pthread_getspecific(gs_keySelf);
 486 }
 487
 488 bool wxThread::IsMain()
 489 {
 490     return (bool)pthread_equal(pthread_self(), gs_tidMain);
 491 }
 492
 493 void wxThread::Yield()
 494 {
 495     sched_yield();
 496 }
 497
 498 void wxThread::Sleep(unsigned long milliseconds)
 499 {
 500     wxUsleep(milliseconds);
 501 }
 502
 503 // -----------------------------------------------------------------------------
 504 // creating thread
 505 // -----------------------------------------------------------------------------
 506
 507 wxThread::wxThread()
 508 {
 509     // add this thread to the global list of all threads
 510     gs_allThreads.Add(this);
 511
 512     p_internal = new wxThreadInternal();
 513 }
 514
 515 wxThreadError wxThread::Create()
 516 {
 517     if (p_internal->GetState() != STATE_NEW)
 518         return wxTHREAD_RUNNING;
 519
 520     // set up the thread attribute: right now, we only set thread priority
 521     pthread_attr_t attr;
 522     pthread_attr_init(&attr);
 523
 524 #ifdef HAVE_THREAD_PRIORITY_FUNCTIONS
 525     int prio;
 526     if ( pthread_attr_getschedpolicy(&attr, &prio) != 0 )
 527     {
 528         wxLogError(_("Cannot retrieve thread scheduling policy."));
 529     }
 530
 531     int min_prio = sched_get_priority_min(prio),
 532         max_prio = sched_get_priority_max(prio);
 533
 534     if ( min_prio == -1 || max_prio == -1 )
 535     {
 536         wxLogError(_("Cannot get priority range for scheduling policy %d."),
 537                    prio);
 538     }
 539     else
 540     {
 541         struct sched_param sp;
 542         pthread_attr_getschedparam(&attr, &sp);
 543         sp.sched_priority = min_prio +
 544                            (p_internal->GetPriority()*(max_prio-min_prio))/100;
 545         pthread_attr_setschedparam(&attr, &sp);
 546     }
 547 #endif // HAVE_THREAD_PRIORITY_FUNCTIONS
 548
 549 #ifdef HAVE_PTHREAD_ATTR_SETSCOPE
 550     // this will make the threads created by this process really concurrent
 551     pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM);
 552 #endif // HAVE_PTHREAD_ATTR_SETSCOPE
 553
 554     // create the new OS thread object
 555     int rc = pthread_create(p_internal->GetIdPtr(), &attr,
 556                             wxThreadInternal::PthreadStart, (void *)this);
 557     pthread_attr_destroy(&attr);
 558
 559     if ( rc != 0 )
 560     {
 561         p_internal->SetState(STATE_EXITED);
 562         return wxTHREAD_NO_RESOURCE;
 563     }
 564
 565     return wxTHREAD_NO_ERROR;
 566 }
 567
 568 wxThreadError wxThread::Run()
 569 {
 570     return p_internal->Run();
 571 }
 572
 573 // -----------------------------------------------------------------------------
 574 // misc accessors
 575 // -----------------------------------------------------------------------------
 576
 577 void wxThread::SetPriority(unsigned int prio)
 578 {
 579     wxCHECK_RET( ((int)WXTHREAD_MIN_PRIORITY <= (int)prio) &&
 580                  ((int)prio <= (int)WXTHREAD_MAX_PRIORITY),
 581                  T("invalid thread priority") );
 582
 583     wxCriticalSectionLocker lock(m_critsect);
 584
 585     switch ( p_internal->GetState() )
 586     {
 587         case STATE_NEW:
 588             // thread not yet started, priority will be set when it is
 589             p_internal->SetPriority(prio);
 590             break;
 591
 592         case STATE_RUNNING:
 593         case STATE_PAUSED:
 594 #ifdef HAVE_THREAD_PRIORITY_FUNCTIONS
 595             {
 596                 struct sched_param sparam;
 597                 sparam.sched_priority = prio;
 598
 599                 if ( pthread_setschedparam(p_internal->GetId(),
 600                                            SCHED_OTHER, &sparam) != 0 )
 601                 {
 602                     wxLogError(_("Failed to set thread priority %d."), prio);
 603                 }
 604             }
 605 #endif // HAVE_THREAD_PRIORITY_FUNCTIONS
 606             break;
 607
 608         case STATE_EXITED:
 609         default:
 610             wxFAIL_MSG(T("impossible to set thread priority in this state"));
 611     }
 612 }
 613
 614 unsigned int wxThread::GetPriority() const
 615 {
 616     wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect);
 617
 618     return p_internal->GetPriority();
 619 }
 620
 621 unsigned long wxThread::GetID() const
 622 {
 623     return (unsigned long)p_internal->GetId();
 624 }
 625
 626 // -----------------------------------------------------------------------------
 627 // pause/resume
 628 // -----------------------------------------------------------------------------
 629
 630 wxThreadError wxThread::Pause()
 631 {
 632     wxCriticalSectionLocker lock(m_critsect);
 633
 634     if ( p_internal->GetState() != STATE_RUNNING )
 635     {
 636         wxLogDebug(T("Can't pause thread which is not running."));
 637
 638         return wxTHREAD_NOT_RUNNING;
 639     }
 640
 641     p_internal->SetState(STATE_PAUSED);
 642
 643     return wxTHREAD_NO_ERROR;
 644 }
 645
 646 wxThreadError wxThread::Resume()
 647 {
 648     wxCriticalSectionLocker lock(m_critsect);
 649
 650     if ( p_internal->GetState() == STATE_PAUSED )
 651     {
 652         m_critsect.Leave();
 653         p_internal->Resume();
 654         m_critsect.Enter();
 655
 656         return wxTHREAD_NO_ERROR;
 657     }
 658     else
 659     {
 660         wxLogDebug(T("Attempt to resume a thread which is not paused."));
 661
 662         return wxTHREAD_MISC_ERROR;
 663     }
 664 }
 665
 666 // -----------------------------------------------------------------------------
 667 // exiting thread
 668 // -----------------------------------------------------------------------------
 669
 670 wxThread::ExitCode wxThread::Delete()
 671 {
 672     if (IsPaused())
 673       Resume();
 674
 675     m_critsect.Enter();
 676     wxThreadState state = p_internal->GetState();
 677
 678     // ask the thread to stop
 679     p_internal->SetCancelFlag();
 680
 681     m_critsect.Leave();
 682
 683     switch ( state )
 684     {
 685         case STATE_NEW:
 686         case STATE_EXITED:
 687             // nothing to do
 688             break;
 689
 690         case STATE_PAUSED:
 691             // resume the thread first
 692             Resume();
 693
 694             // fall through
 695
 696         default:
 697             // wait until the thread stops
 698             p_internal->Wait();
 699     }
 700     //GL: As we must auto-destroy, the destruction must happen here.
 701     delete this;
 702
 703     return NULL;
 704 }
 705
 706 wxThreadError wxThread::Kill()
 707 {
 708     switch ( p_internal->GetState() )
 709     {
 710         case STATE_NEW:
 711         case STATE_EXITED:
 712             return wxTHREAD_NOT_RUNNING;
 713
 714         default:
 715 #ifdef HAVE_PTHREAD_CANCEL
 716             if ( pthread_cancel(p_internal->GetId()) != 0 )
 717 #endif
 718             {
 719                 wxLogError(_("Failed to terminate a thread."));
 720
 721                 return wxTHREAD_MISC_ERROR;
 722             }
 723             //GL: As we must auto-destroy, the destruction must happen here (2).
 724             delete this;
 725
 726             return wxTHREAD_NO_ERROR;
 727     }
 728 }
 729
 730 void wxThread::Exit(void *status)
 731 {
 732     // first call user-level clean up code
 733     OnExit();
 734
 735     // next wake up the threads waiting for us (OTOH, this function won't return
 736     // until someone waited for us!)
 737     p_internal->SignalExit();
 738
 739     p_internal->SetState(STATE_EXITED);
 740
 741     // delete both C++ thread object and terminate the OS thread object
 742     // GL: This is very ugly and buggy ...
 743 //    delete this;
 744     pthread_exit(status);
 745 }
 746
 747 // also test whether we were paused
 748 bool wxThread::TestDestroy()
 749 {
 750     wxCriticalSectionLocker lock(m_critsect);
 751
 752     if ( p_internal->GetState() == STATE_PAUSED )
 753     {
 754         // leave the crit section or the other threads will stop too if they try
 755         // to call any of (seemingly harmless) IsXXX() functions while we sleep
 756         m_critsect.Leave();
 757
 758         p_internal->Pause();
 759
 760         // enter it back before it's finally left in lock object dtor
 761         m_critsect.Enter();
 762     }
 763
 764     return p_internal->WasCancelled();
 765 }
 766
 767 wxThread::~wxThread()
 768 {
 769     m_critsect.Enter();
 770     if (p_internal->GetState() != STATE_EXITED &&
 771         p_internal->GetState() != STATE_NEW)
 772       wxLogDebug(T("The thread is being destroyed althought it is still running ! The application may crash."));
 773
 774     m_critsect.Leave();
 775
 776     delete p_internal;
 777     // remove this thread from the global array
 778     gs_allThreads.Remove(this);
 779 }
 780
 781 // -----------------------------------------------------------------------------
 782 // state tests
 783 // -----------------------------------------------------------------------------
 784
 785 bool wxThread::IsRunning() const
 786 {
 787     wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect);
 788
 789     return p_internal->GetState() == STATE_RUNNING;
 790 }
 791
 792 bool wxThread::IsAlive() const
 793 {
 794     wxCriticalSectionLocker lock((wxCriticalSection&)m_critsect);
 795
 796     switch ( p_internal->GetState() )
 797     {
 798         case STATE_RUNNING:
 799         case STATE_PAUSED:
 800             return TRUE;
 801
 802         default:
 803             return FALSE;
 804     }
 805 }
 806
 807 bool wxThread::IsPaused() const
 808 {
 809     wxCriticalSectionLocker lock((wxCriticalSection&)m_critsect);
 810
 811     return (p_internal->GetState() == STATE_PAUSED);
 812 }
 813
 814 //--------------------------------------------------------------------
 815 // wxThreadModule
 816 //--------------------------------------------------------------------
 817
 818 class wxThreadModule : public wxModule
 819 {
 820 public:
 821     virtual bool OnInit();
 822     virtual void OnExit();
 823
 824 private:
 825     DECLARE_DYNAMIC_CLASS(wxThreadModule)
 826 };
 827
 828 IMPLEMENT_DYNAMIC_CLASS(wxThreadModule, wxModule)
 829
 830 bool wxThreadModule::OnInit()
 831 {
 832     int rc = pthread_key_create(&gs_keySelf, NULL /* dtor function */);
 833     if ( rc != 0 )
 834     {
 835         wxLogSysError(rc, _("Thread module initialization failed: "
 836                             "failed to create thread key"));
 837
 838         return FALSE;
 839     }
 840
 841     gs_mutexGui = new wxMutex();
 842
 843     gs_tidMain = pthread_self();
 844
 845     gs_mutexGui->Lock();
 846
 847     return TRUE;
 848 }
 849
 850 void wxThreadModule::OnExit()
 851 {
 852     wxASSERT_MSG( wxThread::IsMain(), T("only main thread can be here") );
 853
 854     // terminate any threads left
 855     size_t count = gs_allThreads.GetCount();
 856     if ( count != 0u )
 857         wxLogDebug(T("Some threads were not terminated by the application."));
 858
 859     for ( size_t n = 0u; n < count; n++ )
 860     {
 861         // Delete calls the destructor which removes the current entry. We
 862         // should only delete the first one each time.
 863         gs_allThreads[0]->Delete();
 864     }
 865
 866     // destroy GUI mutex
 867     gs_mutexGui->Unlock();
 868
 869     delete gs_mutexGui;
 870
 871     // and free TLD slot
 872     (void)pthread_key_delete(gs_keySelf);
 873 }
 874
 875 // ----------------------------------------------------------------------------
 876 // global functions
 877 // ----------------------------------------------------------------------------
 878
 879 void wxMutexGuiEnter()
 880 {
 881   gs_mutexGui->Lock();
 882 }
 883
 884 void wxMutexGuiLeave()
 885 {
 886   gs_mutexGui->Unlock();
 887 }
 888
 889 #endif
 890   // wxUSE_THREADS