Added wxThread::GetMainId().
[wxWidgets.git] / src / unix / threadpsx.cpp
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: src/unix/threadpsx.cpp
3 // Purpose: wxThread (Posix) Implementation
4 // Author: Original from Wolfram Gloger/Guilhem Lavaux
5 // Modified by: K. S. Sreeram (2002): POSIXified wxCondition, added wxSemaphore
6 // Created: 04/22/98
7 // RCS-ID: $Id$
8 // Copyright: (c) Wolfram Gloger (1996, 1997)
9 // Guilhem Lavaux (1998)
10 // Vadim Zeitlin (1999-2002)
11 // Robert Roebling (1999)
12 // K. S. Sreeram (2002)
13 // Licence: wxWindows licence
14 /////////////////////////////////////////////////////////////////////////////
15
16 // ============================================================================
17 // declaration
18 // ============================================================================
19
20 // ----------------------------------------------------------------------------
21 // headers
22 // ----------------------------------------------------------------------------
23
24 // for compilers that support precompilation, includes "wx.h".
25 #include "wx/wxprec.h"
26
27 #if wxUSE_THREADS
28
29 #include "wx/thread.h"
30 #include "wx/except.h"
31
32 #ifndef WX_PRECOMP
33 #include "wx/app.h"
34 #include "wx/dynarray.h"
35 #include "wx/intl.h"
36 #include "wx/log.h"
37 #include "wx/utils.h"
38 #include "wx/timer.h"
39 #include "wx/stopwatch.h"
40 #include "wx/module.h"
41 #endif
42
43 #include <stdio.h>
44 #include <unistd.h>
45 #include <pthread.h>
46 #include <errno.h>
47 #include <time.h>
48 #ifdef HAVE_SCHED_H
49 #include <sched.h>
50 #endif
51
52 #ifdef HAVE_THR_SETCONCURRENCY
53 #include <thread.h>
54 #endif
55
56 // we use wxFFile under Linux in GetCPUCount()
57 #ifdef __LINUX__
58 #include "wx/ffile.h"
59 // For setpriority.
60 #include <sys/time.h>
61 #include <sys/resource.h>
62 #endif
63
64 #ifdef __VMS
65 #define THR_ID(thr) ((long long)(thr)->GetId())
66 #else
67 #define THR_ID(thr) ((long)(thr)->GetId())
68 #endif
69
70 // ----------------------------------------------------------------------------
71 // constants
72 // ----------------------------------------------------------------------------
73
74 // the possible states of the thread and transitions from them
75 enum wxThreadState
76 {
77 STATE_NEW, // didn't start execution yet (=> RUNNING)
78 STATE_RUNNING, // running (=> PAUSED or EXITED)
79 STATE_PAUSED, // suspended (=> RUNNING or EXITED)
80 STATE_EXITED // thread doesn't exist any more
81 };
82
83 // the exit value of a thread which has been cancelled
84 static const wxThread::ExitCode EXITCODE_CANCELLED = (wxThread::ExitCode)-1;
85
86 // trace mask for wxThread operations
87 #define TRACE_THREADS _T("thread")
88
89 // you can get additional debugging messages for the semaphore operations
90 #define TRACE_SEMA _T("semaphore")
91
92 // ----------------------------------------------------------------------------
93 // private functions
94 // ----------------------------------------------------------------------------
95
96 static void ScheduleThreadForDeletion();
97 static void DeleteThread(wxThread *This);
98
99 // ----------------------------------------------------------------------------
100 // private classes
101 // ----------------------------------------------------------------------------
102
103 // an (non owning) array of pointers to threads
104 WX_DEFINE_ARRAY_PTR(wxThread *, wxArrayThread);
105
106 // an entry for a thread we can wait for
107
108 // -----------------------------------------------------------------------------
109 // global data
110 // -----------------------------------------------------------------------------
111
112 // we keep the list of all threads created by the application to be able to
113 // terminate them on exit if there are some left - otherwise the process would
114 // be left in memory
115 static wxArrayThread gs_allThreads;
116
117 // a mutex to protect gs_allThreads
118 static wxMutex *gs_mutexAllThreads = NULL;
119
120 // the id of the main thread
121 //
122 // we suppose that 0 is not a valid pthread_t value but in principle this might
123 // be false (e.g. if it's a selector-like value), wxThread::IsMain() would need
124 // to be updated in such case
125 wxThreadIdType wxThread::ms_idMainThread = 0;
126
127 // the key for the pointer to the associated wxThread object
128 static pthread_key_t gs_keySelf;
129
130 // the number of threads which are being deleted - the program won't exit
131 // until there are any left
132 static size_t gs_nThreadsBeingDeleted = 0;
133
134 // a mutex to protect gs_nThreadsBeingDeleted
135 static wxMutex *gs_mutexDeleteThread = NULL;
136
137 // and a condition variable which will be signaled when all
138 // gs_nThreadsBeingDeleted will have been deleted
139 static wxCondition *gs_condAllDeleted = NULL;
140
141 // this mutex must be acquired before any call to a GUI function
142 // (it's not inside #if wxUSE_GUI because this file is compiled as part
143 // of wxBase)
144 static wxMutex *gs_mutexGui = NULL;
145
146 // when we wait for a thread to exit, we're blocking on a condition which the
147 // thread signals in its SignalExit() method -- but this condition can't be a
148 // member of the thread itself as a detached thread may delete itself at any
149 // moment and accessing the condition member of the thread after this would
150 // result in a disaster
151 //
152 // so instead we maintain a global list of the structs below for the threads
153 // we're interested in waiting on
154
155 // ============================================================================
156 // wxMutex implementation
157 // ============================================================================
158
159 // ----------------------------------------------------------------------------
160 // wxMutexInternal
161 // ----------------------------------------------------------------------------
162
163 // this is a simple wrapper around pthread_mutex_t which provides error
164 // checking
165 class wxMutexInternal
166 {
167 public:
168 wxMutexInternal(wxMutexType mutexType);
169 ~wxMutexInternal();
170
171 wxMutexError Lock();
172 wxMutexError Lock(unsigned long ms);
173 wxMutexError TryLock();
174 wxMutexError Unlock();
175
176 bool IsOk() const { return m_isOk; }
177
178 private:
179 // convert the result of pthread_mutex_[timed]lock() call to wx return code
180 wxMutexError HandleLockResult(int err);
181
182 private:
183 pthread_mutex_t m_mutex;
184 bool m_isOk;
185 wxMutexType m_type;
186 unsigned long m_owningThread;
187
188 // wxConditionInternal uses our m_mutex
189 friend class wxConditionInternal;
190 };
191
192 #if defined(HAVE_PTHREAD_MUTEXATTR_T) && \
193 wxUSE_UNIX && !defined(HAVE_PTHREAD_MUTEXATTR_SETTYPE_DECL)
194 // on some systems pthread_mutexattr_settype() is not in the headers (but it is
195 // in the library, otherwise we wouldn't compile this code at all)
196 extern "C" int pthread_mutexattr_settype(pthread_mutexattr_t *, int);
197 #endif
198
199 wxMutexInternal::wxMutexInternal(wxMutexType mutexType)
200 {
201 m_type = mutexType;
202 m_owningThread = 0;
203
204 int err;
205 switch ( mutexType )
206 {
207 case wxMUTEX_RECURSIVE:
208 // support recursive locks like Win32, i.e. a thread can lock a
209 // mutex which it had itself already locked
210 //
211 // unfortunately initialization of recursive mutexes is non
212 // portable, so try several methods
213 #ifdef HAVE_PTHREAD_MUTEXATTR_T
214 {
215 pthread_mutexattr_t attr;
216 pthread_mutexattr_init(&attr);
217 pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
218
219 err = pthread_mutex_init(&m_mutex, &attr);
220 }
221 #elif defined(HAVE_PTHREAD_RECURSIVE_MUTEX_INITIALIZER)
222 // we can use this only as initializer so we have to assign it
223 // first to a temp var - assigning directly to m_mutex wouldn't
224 // even compile
225 {
226 pthread_mutex_t mutex = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
227 m_mutex = mutex;
228 }
229 #else // no recursive mutexes
230 err = EINVAL;
231 #endif // HAVE_PTHREAD_MUTEXATTR_T/...
232 break;
233
234 default:
235 wxFAIL_MSG( _T("unknown mutex type") );
236 // fall through
237
238 case wxMUTEX_DEFAULT:
239 err = pthread_mutex_init(&m_mutex, NULL);
240 break;
241 }
242
243 m_isOk = err == 0;
244 if ( !m_isOk )
245 {
246 wxLogApiError( wxT("pthread_mutex_init()"), err);
247 }
248 }
249
250 wxMutexInternal::~wxMutexInternal()
251 {
252 if ( m_isOk )
253 {
254 int err = pthread_mutex_destroy(&m_mutex);
255 if ( err != 0 )
256 {
257 wxLogApiError( wxT("pthread_mutex_destroy()"), err);
258 }
259 }
260 }
261
262 wxMutexError wxMutexInternal::Lock()
263 {
264 if ((m_type == wxMUTEX_DEFAULT) && (m_owningThread != 0))
265 {
266 if (m_owningThread == wxThread::GetCurrentId())
267 return wxMUTEX_DEAD_LOCK;
268 }
269
270 return HandleLockResult(pthread_mutex_lock(&m_mutex));
271 }
272
273 wxMutexError wxMutexInternal::Lock(unsigned long ms)
274 {
275 #ifdef HAVE_PTHREAD_MUTEX_TIMEDLOCK
276 static const long MSEC_IN_SEC = 1000;
277 static const long NSEC_IN_MSEC = 1000000;
278 static const long NSEC_IN_USEC = 1000;
279 static const long NSEC_IN_SEC = MSEC_IN_SEC * NSEC_IN_MSEC;
280
281 time_t seconds = ms/MSEC_IN_SEC;
282 long nanoseconds = (ms % MSEC_IN_SEC) * NSEC_IN_MSEC;
283 timespec ts = { 0, 0 };
284
285 // normally we should use clock_gettime(CLOCK_REALTIME) here but this
286 // function is in librt and we don't link with it currently, so use
287 // gettimeofday() instead -- if it turns out that this is really too
288 // imprecise, we should modify configure to check if clock_gettime() is
289 // available and whether it requires -lrt and use it instead
290 #if 0
291 if ( clock_gettime(CLOCK_REALTIME, &ts) == 0 )
292 {
293 }
294 #else
295 struct timeval tv;
296 if ( wxGetTimeOfDay(&tv) != -1 )
297 {
298 ts.tv_sec = tv.tv_sec;
299 ts.tv_nsec = tv.tv_usec*NSEC_IN_USEC;
300 }
301 #endif
302 else // fall back on system timer
303 {
304 ts.tv_sec = time(NULL);
305 }
306
307 ts.tv_sec += seconds;
308 ts.tv_nsec += nanoseconds;
309 if ( ts.tv_nsec > NSEC_IN_SEC )
310 {
311 ts.tv_sec += 1;
312 ts.tv_nsec -= NSEC_IN_SEC;
313 }
314
315 return HandleLockResult(pthread_mutex_timedlock(&m_mutex, &ts));
316 #else // !HAVE_PTHREAD_MUTEX_TIMEDLOCK
317 wxUnusedVar(ms);
318
319 return wxMUTEX_MISC_ERROR;
320 #endif // HAVE_PTHREAD_MUTEX_TIMEDLOCK/!HAVE_PTHREAD_MUTEX_TIMEDLOCK
321 }
322
323 wxMutexError wxMutexInternal::HandleLockResult(int err)
324 {
325 // wxPrintf( "err %d\n", err );
326
327 switch ( err )
328 {
329 case EDEADLK:
330 // only error checking mutexes return this value and so it's an
331 // unexpected situation -- hence use assert, not wxLogDebug
332 wxFAIL_MSG( _T("mutex deadlock prevented") );
333 return wxMUTEX_DEAD_LOCK;
334
335 case EINVAL:
336 wxLogDebug(_T("pthread_mutex_[timed]lock(): mutex not initialized"));
337 break;
338
339 case ETIMEDOUT:
340 return wxMUTEX_TIMEOUT;
341
342 case 0:
343 if (m_type == wxMUTEX_DEFAULT)
344 m_owningThread = wxThread::GetCurrentId();
345 return wxMUTEX_NO_ERROR;
346
347 default:
348 wxLogApiError(_T("pthread_mutex_[timed]lock()"), err);
349 }
350
351 return wxMUTEX_MISC_ERROR;
352 }
353
354
355 wxMutexError wxMutexInternal::TryLock()
356 {
357 int err = pthread_mutex_trylock(&m_mutex);
358 switch ( err )
359 {
360 case EBUSY:
361 // not an error: mutex is already locked, but we're prepared for
362 // this
363 return wxMUTEX_BUSY;
364
365 case EINVAL:
366 wxLogDebug(_T("pthread_mutex_trylock(): mutex not initialized."));
367 break;
368
369 case 0:
370 if (m_type == wxMUTEX_DEFAULT)
371 m_owningThread = wxThread::GetCurrentId();
372 return wxMUTEX_NO_ERROR;
373
374 default:
375 wxLogApiError(_T("pthread_mutex_trylock()"), err);
376 }
377
378 return wxMUTEX_MISC_ERROR;
379 }
380
381 wxMutexError wxMutexInternal::Unlock()
382 {
383 m_owningThread = 0;
384
385 int err = pthread_mutex_unlock(&m_mutex);
386 switch ( err )
387 {
388 case EPERM:
389 // we don't own the mutex
390 return wxMUTEX_UNLOCKED;
391
392 case EINVAL:
393 wxLogDebug(_T("pthread_mutex_unlock(): mutex not initialized."));
394 break;
395
396 case 0:
397 return wxMUTEX_NO_ERROR;
398
399 default:
400 wxLogApiError(_T("pthread_mutex_unlock()"), err);
401 }
402
403 return wxMUTEX_MISC_ERROR;
404 }
405
406 // ===========================================================================
407 // wxCondition implementation
408 // ===========================================================================
409
410 // ---------------------------------------------------------------------------
411 // wxConditionInternal
412 // ---------------------------------------------------------------------------
413
414 // this is a wrapper around pthread_cond_t associated with a wxMutex (and hence
415 // with a pthread_mutex_t)
416 class wxConditionInternal
417 {
418 public:
419 wxConditionInternal(wxMutex& mutex);
420 ~wxConditionInternal();
421
422 bool IsOk() const { return m_isOk && m_mutex.IsOk(); }
423
424 wxCondError Wait();
425 wxCondError WaitTimeout(unsigned long milliseconds);
426
427 wxCondError Signal();
428 wxCondError Broadcast();
429
430 private:
431 // get the POSIX mutex associated with us
432 pthread_mutex_t *GetPMutex() const { return &m_mutex.m_internal->m_mutex; }
433
434 wxMutex& m_mutex;
435 pthread_cond_t m_cond;
436
437 bool m_isOk;
438 };
439
440 wxConditionInternal::wxConditionInternal(wxMutex& mutex)
441 : m_mutex(mutex)
442 {
443 int err = pthread_cond_init(&m_cond, NULL /* default attributes */);
444
445 m_isOk = err == 0;
446
447 if ( !m_isOk )
448 {
449 wxLogApiError(_T("pthread_cond_init()"), err);
450 }
451 }
452
453 wxConditionInternal::~wxConditionInternal()
454 {
455 if ( m_isOk )
456 {
457 int err = pthread_cond_destroy(&m_cond);
458 if ( err != 0 )
459 {
460 wxLogApiError(_T("pthread_cond_destroy()"), err);
461 }
462 }
463 }
464
465 wxCondError wxConditionInternal::Wait()
466 {
467 int err = pthread_cond_wait(&m_cond, GetPMutex());
468 if ( err != 0 )
469 {
470 wxLogApiError(_T("pthread_cond_wait()"), err);
471
472 return wxCOND_MISC_ERROR;
473 }
474
475 return wxCOND_NO_ERROR;
476 }
477
478 wxCondError wxConditionInternal::WaitTimeout(unsigned long milliseconds)
479 {
480 wxLongLong curtime = wxGetLocalTimeMillis();
481 curtime += milliseconds;
482 wxLongLong temp = curtime / 1000;
483 int sec = temp.GetLo();
484 temp *= 1000;
485 temp = curtime - temp;
486 int millis = temp.GetLo();
487
488 timespec tspec;
489
490 tspec.tv_sec = sec;
491 tspec.tv_nsec = millis * 1000L * 1000L;
492
493 int err = pthread_cond_timedwait( &m_cond, GetPMutex(), &tspec );
494 switch ( err )
495 {
496 case ETIMEDOUT:
497 return wxCOND_TIMEOUT;
498
499 case 0:
500 return wxCOND_NO_ERROR;
501
502 default:
503 wxLogApiError(_T("pthread_cond_timedwait()"), err);
504 }
505
506 return wxCOND_MISC_ERROR;
507 }
508
509 wxCondError wxConditionInternal::Signal()
510 {
511 int err = pthread_cond_signal(&m_cond);
512 if ( err != 0 )
513 {
514 wxLogApiError(_T("pthread_cond_signal()"), err);
515
516 return wxCOND_MISC_ERROR;
517 }
518
519 return wxCOND_NO_ERROR;
520 }
521
522 wxCondError wxConditionInternal::Broadcast()
523 {
524 int err = pthread_cond_broadcast(&m_cond);
525 if ( err != 0 )
526 {
527 wxLogApiError(_T("pthread_cond_broadcast()"), err);
528
529 return wxCOND_MISC_ERROR;
530 }
531
532 return wxCOND_NO_ERROR;
533 }
534
535 // ===========================================================================
536 // wxSemaphore implementation
537 // ===========================================================================
538
539 // ---------------------------------------------------------------------------
540 // wxSemaphoreInternal
541 // ---------------------------------------------------------------------------
542
543 // we implement the semaphores using mutexes and conditions instead of using
544 // the sem_xxx() POSIX functions because they're not widely available and also
545 // because it's impossible to implement WaitTimeout() using them
546 class wxSemaphoreInternal
547 {
548 public:
549 wxSemaphoreInternal(int initialcount, int maxcount);
550
551 bool IsOk() const { return m_isOk; }
552
553 wxSemaError Wait();
554 wxSemaError TryWait();
555 wxSemaError WaitTimeout(unsigned long milliseconds);
556
557 wxSemaError Post();
558
559 private:
560 wxMutex m_mutex;
561 wxCondition m_cond;
562
563 size_t m_count,
564 m_maxcount;
565
566 bool m_isOk;
567 };
568
569 wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount)
570 : m_cond(m_mutex)
571 {
572
573 if ( (initialcount < 0 || maxcount < 0) ||
574 ((maxcount > 0) && (initialcount > maxcount)) )
575 {
576 wxFAIL_MSG( _T("wxSemaphore: invalid initial or maximal count") );
577
578 m_isOk = false;
579 }
580 else
581 {
582 m_maxcount = (size_t)maxcount;
583 m_count = (size_t)initialcount;
584 }
585
586 m_isOk = m_mutex.IsOk() && m_cond.IsOk();
587 }
588
589 wxSemaError wxSemaphoreInternal::Wait()
590 {
591 wxMutexLocker locker(m_mutex);
592
593 while ( m_count == 0 )
594 {
595 wxLogTrace(TRACE_SEMA,
596 _T("Thread %p waiting for semaphore to become signalled"),
597 wxThread::GetCurrentId());
598
599 if ( m_cond.Wait() != wxCOND_NO_ERROR )
600 return wxSEMA_MISC_ERROR;
601
602 wxLogTrace(TRACE_SEMA,
603 _T("Thread %p finished waiting for semaphore, count = %lu"),
604 wxThread::GetCurrentId(), (unsigned long)m_count);
605 }
606
607 m_count--;
608
609 return wxSEMA_NO_ERROR;
610 }
611
612 wxSemaError wxSemaphoreInternal::TryWait()
613 {
614 wxMutexLocker locker(m_mutex);
615
616 if ( m_count == 0 )
617 return wxSEMA_BUSY;
618
619 m_count--;
620
621 return wxSEMA_NO_ERROR;
622 }
623
624 wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long milliseconds)
625 {
626 wxMutexLocker locker(m_mutex);
627
628 wxLongLong startTime = wxGetLocalTimeMillis();
629
630 while ( m_count == 0 )
631 {
632 wxLongLong elapsed = wxGetLocalTimeMillis() - startTime;
633 long remainingTime = (long)milliseconds - (long)elapsed.GetLo();
634 if ( remainingTime <= 0 )
635 {
636 // timeout
637 return wxSEMA_TIMEOUT;
638 }
639
640 switch ( m_cond.WaitTimeout(remainingTime) )
641 {
642 case wxCOND_TIMEOUT:
643 return wxSEMA_TIMEOUT;
644
645 default:
646 return wxSEMA_MISC_ERROR;
647
648 case wxCOND_NO_ERROR:
649 ;
650 }
651 }
652
653 m_count--;
654
655 return wxSEMA_NO_ERROR;
656 }
657
658 wxSemaError wxSemaphoreInternal::Post()
659 {
660 wxMutexLocker locker(m_mutex);
661
662 if ( m_maxcount > 0 && m_count == m_maxcount )
663 {
664 return wxSEMA_OVERFLOW;
665 }
666
667 m_count++;
668
669 wxLogTrace(TRACE_SEMA,
670 _T("Thread %p about to signal semaphore, count = %lu"),
671 wxThread::GetCurrentId(), (unsigned long)m_count);
672
673 return m_cond.Signal() == wxCOND_NO_ERROR ? wxSEMA_NO_ERROR
674 : wxSEMA_MISC_ERROR;
675 }
676
677 // ===========================================================================
678 // wxThread implementation
679 // ===========================================================================
680
681 // the thread callback functions must have the C linkage
682 extern "C"
683 {
684
685 #ifdef wxHAVE_PTHREAD_CLEANUP
686 // thread exit function
687 void wxPthreadCleanup(void *ptr);
688 #endif // wxHAVE_PTHREAD_CLEANUP
689
690 void *wxPthreadStart(void *ptr);
691
692 } // extern "C"
693
694 // ----------------------------------------------------------------------------
695 // wxThreadInternal
696 // ----------------------------------------------------------------------------
697
698 class wxThreadInternal
699 {
700 public:
701 wxThreadInternal();
702 ~wxThreadInternal();
703
704 // thread entry function
705 static void *PthreadStart(wxThread *thread);
706
707 // thread actions
708 // start the thread
709 wxThreadError Run();
710 // unblock the thread allowing it to run
711 void SignalRun() { m_semRun.Post(); }
712 // ask the thread to terminate
713 void Wait();
714 // go to sleep until Resume() is called
715 void Pause();
716 // resume the thread
717 void Resume();
718
719 // accessors
720 // priority
721 int GetPriority() const { return m_prio; }
722 void SetPriority(int prio) { m_prio = prio; }
723 // state
724 wxThreadState GetState() const { return m_state; }
725 void SetState(wxThreadState state)
726 {
727 #if wxUSE_LOG_TRACE
728 static const wxChar *stateNames[] =
729 {
730 _T("NEW"),
731 _T("RUNNING"),
732 _T("PAUSED"),
733 _T("EXITED"),
734 };
735
736 wxLogTrace(TRACE_THREADS, _T("Thread %p: %s => %s."),
737 GetId(), stateNames[m_state], stateNames[state]);
738 #endif // wxUSE_LOG_TRACE
739
740 m_state = state;
741 }
742 // id
743 pthread_t GetId() const { return m_threadId; }
744 pthread_t *GetIdPtr() { return &m_threadId; }
745 // "cancelled" flag
746 void SetCancelFlag() { m_cancelled = true; }
747 bool WasCancelled() const { return m_cancelled; }
748 // exit code
749 void SetExitCode(wxThread::ExitCode exitcode) { m_exitcode = exitcode; }
750 wxThread::ExitCode GetExitCode() const { return m_exitcode; }
751
752 // the pause flag
753 void SetReallyPaused(bool paused) { m_isPaused = paused; }
754 bool IsReallyPaused() const { return m_isPaused; }
755
756 // tell the thread that it is a detached one
757 void Detach()
758 {
759 wxCriticalSectionLocker lock(m_csJoinFlag);
760
761 m_shouldBeJoined = false;
762 m_isDetached = true;
763 }
764
765 #ifdef wxHAVE_PTHREAD_CLEANUP
766 // this is used by wxPthreadCleanup() only
767 static void Cleanup(wxThread *thread);
768 #endif // wxHAVE_PTHREAD_CLEANUP
769
770 private:
771 pthread_t m_threadId; // id of the thread
772 wxThreadState m_state; // see wxThreadState enum
773 int m_prio; // in wxWidgets units: from 0 to 100
774
775 // this flag is set when the thread should terminate
776 bool m_cancelled;
777
778 // this flag is set when the thread is blocking on m_semSuspend
779 bool m_isPaused;
780
781 // the thread exit code - only used for joinable (!detached) threads and
782 // is only valid after the thread termination
783 wxThread::ExitCode m_exitcode;
784
785 // many threads may call Wait(), but only one of them should call
786 // pthread_join(), so we have to keep track of this
787 wxCriticalSection m_csJoinFlag;
788 bool m_shouldBeJoined;
789 bool m_isDetached;
790
791 // this semaphore is posted by Run() and the threads Entry() is not
792 // called before it is done
793 wxSemaphore m_semRun;
794
795 // this one is signaled when the thread should resume after having been
796 // Pause()d
797 wxSemaphore m_semSuspend;
798 };
799
800 // ----------------------------------------------------------------------------
801 // thread startup and exit functions
802 // ----------------------------------------------------------------------------
803
804 void *wxPthreadStart(void *ptr)
805 {
806 return wxThreadInternal::PthreadStart((wxThread *)ptr);
807 }
808
809 void *wxThreadInternal::PthreadStart(wxThread *thread)
810 {
811 wxThreadInternal *pthread = thread->m_internal;
812
813 wxLogTrace(TRACE_THREADS, _T("Thread %p started."), THR_ID(pthread));
814
815 // associate the thread pointer with the newly created thread so that
816 // wxThread::This() will work
817 int rc = pthread_setspecific(gs_keySelf, thread);
818 if ( rc != 0 )
819 {
820 wxLogSysError(rc, _("Cannot start thread: error writing TLS"));
821
822 return (void *)-1;
823 }
824
825 // have to declare this before pthread_cleanup_push() which defines a
826 // block!
827 bool dontRunAtAll;
828
829 #ifdef wxHAVE_PTHREAD_CLEANUP
830 // install the cleanup handler which will be called if the thread is
831 // cancelled
832 pthread_cleanup_push(wxPthreadCleanup, thread);
833 #endif // wxHAVE_PTHREAD_CLEANUP
834
835 // wait for the semaphore to be posted from Run()
836 pthread->m_semRun.Wait();
837
838 // test whether we should run the run at all - may be it was deleted
839 // before it started to Run()?
840 {
841 wxCriticalSectionLocker lock(thread->m_critsect);
842
843 dontRunAtAll = pthread->GetState() == STATE_NEW &&
844 pthread->WasCancelled();
845 }
846
847 if ( !dontRunAtAll )
848 {
849 // call the main entry
850 wxLogTrace(TRACE_THREADS,
851 _T("Thread %p about to enter its Entry()."),
852 THR_ID(pthread));
853
854 wxTRY
855 {
856 pthread->m_exitcode = thread->Entry();
857
858 wxLogTrace(TRACE_THREADS,
859 _T("Thread %p Entry() returned %lu."),
860 THR_ID(pthread), wxPtrToUInt(pthread->m_exitcode));
861 }
862 wxCATCH_ALL( wxTheApp->OnUnhandledException(); )
863
864 {
865 wxCriticalSectionLocker lock(thread->m_critsect);
866
867 // change the state of the thread to "exited" so that
868 // wxPthreadCleanup handler won't do anything from now (if it's
869 // called before we do pthread_cleanup_pop below)
870 pthread->SetState(STATE_EXITED);
871 }
872 }
873
874 // NB: pthread_cleanup_push/pop() are macros and pop contains the matching
875 // '}' for the '{' in push, so they must be used in the same block!
876 #ifdef wxHAVE_PTHREAD_CLEANUP
877 #ifdef __DECCXX
878 // under Tru64 we get a warning from macro expansion
879 #pragma message save
880 #pragma message disable(declbutnotref)
881 #endif
882
883 // remove the cleanup handler without executing it
884 pthread_cleanup_pop(FALSE);
885
886 #ifdef __DECCXX
887 #pragma message restore
888 #endif
889 #endif // wxHAVE_PTHREAD_CLEANUP
890
891 if ( dontRunAtAll )
892 {
893 // FIXME: deleting a possibly joinable thread here???
894 delete thread;
895
896 return EXITCODE_CANCELLED;
897 }
898 else
899 {
900 // terminate the thread
901 thread->Exit(pthread->m_exitcode);
902
903 wxFAIL_MSG(wxT("wxThread::Exit() can't return."));
904
905 return NULL;
906 }
907 }
908
909 #ifdef wxHAVE_PTHREAD_CLEANUP
910
911 // this handler is called when the thread is cancelled
912 extern "C" void wxPthreadCleanup(void *ptr)
913 {
914 wxThreadInternal::Cleanup((wxThread *)ptr);
915 }
916
917 void wxThreadInternal::Cleanup(wxThread *thread)
918 {
919 if (pthread_getspecific(gs_keySelf) == 0) return;
920 {
921 wxCriticalSectionLocker lock(thread->m_critsect);
922 if ( thread->m_internal->GetState() == STATE_EXITED )
923 {
924 // thread is already considered as finished.
925 return;
926 }
927 }
928
929 // exit the thread gracefully
930 thread->Exit(EXITCODE_CANCELLED);
931 }
932
933 #endif // wxHAVE_PTHREAD_CLEANUP
934
935 // ----------------------------------------------------------------------------
936 // wxThreadInternal
937 // ----------------------------------------------------------------------------
938
939 wxThreadInternal::wxThreadInternal()
940 {
941 m_state = STATE_NEW;
942 m_cancelled = false;
943 m_prio = WXTHREAD_DEFAULT_PRIORITY;
944 m_threadId = 0;
945 m_exitcode = 0;
946
947 // set to true only when the thread starts waiting on m_semSuspend
948 m_isPaused = false;
949
950 // defaults for joinable threads
951 m_shouldBeJoined = true;
952 m_isDetached = false;
953 }
954
955 wxThreadInternal::~wxThreadInternal()
956 {
957 }
958
959 wxThreadError wxThreadInternal::Run()
960 {
961 wxCHECK_MSG( GetState() == STATE_NEW, wxTHREAD_RUNNING,
962 wxT("thread may only be started once after Create()") );
963
964 SetState(STATE_RUNNING);
965
966 // wake up threads waiting for our start
967 SignalRun();
968
969 return wxTHREAD_NO_ERROR;
970 }
971
972 void wxThreadInternal::Wait()
973 {
974 wxCHECK_RET( !m_isDetached, _T("can't wait for a detached thread") );
975
976 // if the thread we're waiting for is waiting for the GUI mutex, we will
977 // deadlock so make sure we release it temporarily
978 if ( wxThread::IsMain() )
979 wxMutexGuiLeave();
980
981 wxLogTrace(TRACE_THREADS,
982 _T("Starting to wait for thread %p to exit."),
983 THR_ID(this));
984
985 // to avoid memory leaks we should call pthread_join(), but it must only be
986 // done once so use a critical section to serialize the code below
987 {
988 wxCriticalSectionLocker lock(m_csJoinFlag);
989
990 if ( m_shouldBeJoined )
991 {
992 // FIXME shouldn't we set cancellation type to DISABLED here? If
993 // we're cancelled inside pthread_join(), things will almost
994 // certainly break - but if we disable the cancellation, we
995 // might deadlock
996 if ( pthread_join(GetId(), &m_exitcode) != 0 )
997 {
998 // this is a serious problem, so use wxLogError and not
999 // wxLogDebug: it is possible to bring the system to its knees
1000 // by creating too many threads and not joining them quite
1001 // easily
1002 wxLogError(_("Failed to join a thread, potential memory leak detected - please restart the program"));
1003 }
1004
1005 m_shouldBeJoined = false;
1006 }
1007 }
1008
1009 // reacquire GUI mutex
1010 if ( wxThread::IsMain() )
1011 wxMutexGuiEnter();
1012 }
1013
1014 void wxThreadInternal::Pause()
1015 {
1016 // the state is set from the thread which pauses us first, this function
1017 // is called later so the state should have been already set
1018 wxCHECK_RET( m_state == STATE_PAUSED,
1019 wxT("thread must first be paused with wxThread::Pause().") );
1020
1021 wxLogTrace(TRACE_THREADS,
1022 _T("Thread %p goes to sleep."), THR_ID(this));
1023
1024 // wait until the semaphore is Post()ed from Resume()
1025 m_semSuspend.Wait();
1026 }
1027
1028 void wxThreadInternal::Resume()
1029 {
1030 wxCHECK_RET( m_state == STATE_PAUSED,
1031 wxT("can't resume thread which is not suspended.") );
1032
1033 // the thread might be not actually paused yet - if there were no call to
1034 // TestDestroy() since the last call to Pause() for example
1035 if ( IsReallyPaused() )
1036 {
1037 wxLogTrace(TRACE_THREADS,
1038 _T("Waking up thread %p"), THR_ID(this));
1039
1040 // wake up Pause()
1041 m_semSuspend.Post();
1042
1043 // reset the flag
1044 SetReallyPaused(false);
1045 }
1046 else
1047 {
1048 wxLogTrace(TRACE_THREADS,
1049 _T("Thread %p is not yet really paused"), THR_ID(this));
1050 }
1051
1052 SetState(STATE_RUNNING);
1053 }
1054
1055 // -----------------------------------------------------------------------------
1056 // wxThread static functions
1057 // -----------------------------------------------------------------------------
1058
1059 wxThread *wxThread::This()
1060 {
1061 return (wxThread *)pthread_getspecific(gs_keySelf);
1062 }
1063
1064 void wxThread::Yield()
1065 {
1066 #ifdef HAVE_SCHED_YIELD
1067 sched_yield();
1068 #endif
1069 }
1070
1071 int wxThread::GetCPUCount()
1072 {
1073 #if defined(_SC_NPROCESSORS_ONLN)
1074 // this works for Solaris and Linux 2.6
1075 int rc = sysconf(_SC_NPROCESSORS_ONLN);
1076 if ( rc != -1 )
1077 {
1078 return rc;
1079 }
1080 #elif defined(__LINUX__) && wxUSE_FFILE
1081 // read from proc (can't use wxTextFile here because it's a special file:
1082 // it has 0 size but still can be read from)
1083 wxLogNull nolog;
1084
1085 wxFFile file(_T("/proc/cpuinfo"));
1086 if ( file.IsOpened() )
1087 {
1088 // slurp the whole file
1089 wxString s;
1090 if ( file.ReadAll(&s) )
1091 {
1092 // (ab)use Replace() to find the number of "processor: num" strings
1093 size_t count = s.Replace(_T("processor\t:"), _T(""));
1094 if ( count > 0 )
1095 {
1096 return count;
1097 }
1098
1099 wxLogDebug(_T("failed to parse /proc/cpuinfo"));
1100 }
1101 else
1102 {
1103 wxLogDebug(_T("failed to read /proc/cpuinfo"));
1104 }
1105 }
1106 #endif // different ways to get number of CPUs
1107
1108 // unknown
1109 return -1;
1110 }
1111
1112 wxThreadIdType wxThread::GetCurrentId()
1113 {
1114 return (wxThreadIdType)pthread_self();
1115 }
1116
1117
1118 bool wxThread::SetConcurrency(size_t level)
1119 {
1120 #ifdef HAVE_THR_SETCONCURRENCY
1121 int rc = thr_setconcurrency(level);
1122 if ( rc != 0 )
1123 {
1124 wxLogSysError(rc, _T("thr_setconcurrency() failed"));
1125 }
1126
1127 return rc == 0;
1128 #else // !HAVE_THR_SETCONCURRENCY
1129 // ok only for the default value
1130 return level == 0;
1131 #endif // HAVE_THR_SETCONCURRENCY/!HAVE_THR_SETCONCURRENCY
1132 }
1133
1134 // -----------------------------------------------------------------------------
1135 // creating thread
1136 // -----------------------------------------------------------------------------
1137
1138 wxThread::wxThread(wxThreadKind kind)
1139 {
1140 // add this thread to the global list of all threads
1141 {
1142 wxMutexLocker lock(*gs_mutexAllThreads);
1143
1144 gs_allThreads.Add(this);
1145 }
1146
1147 m_internal = new wxThreadInternal();
1148
1149 m_isDetached = kind == wxTHREAD_DETACHED;
1150 }
1151
1152 #ifdef HAVE_PTHREAD_ATTR_SETSTACKSIZE
1153 #define WXUNUSED_STACKSIZE(identifier) identifier
1154 #else
1155 #define WXUNUSED_STACKSIZE(identifier) WXUNUSED(identifier)
1156 #endif
1157
1158 wxThreadError wxThread::Create(unsigned int WXUNUSED_STACKSIZE(stackSize))
1159 {
1160 if ( m_internal->GetState() != STATE_NEW )
1161 {
1162 // don't recreate thread
1163 return wxTHREAD_RUNNING;
1164 }
1165
1166 // set up the thread attribute: right now, we only set thread priority
1167 pthread_attr_t attr;
1168 pthread_attr_init(&attr);
1169
1170 #ifdef HAVE_PTHREAD_ATTR_SETSTACKSIZE
1171 if (stackSize)
1172 pthread_attr_setstacksize(&attr, stackSize);
1173 #endif
1174
1175 #ifdef HAVE_THREAD_PRIORITY_FUNCTIONS
1176 int policy;
1177 if ( pthread_attr_getschedpolicy(&attr, &policy) != 0 )
1178 {
1179 wxLogError(_("Cannot retrieve thread scheduling policy."));
1180 }
1181
1182 #ifdef __VMS__
1183 /* the pthread.h contains too many spaces. This is a work-around */
1184 # undef sched_get_priority_max
1185 #undef sched_get_priority_min
1186 #define sched_get_priority_max(_pol_) \
1187 (_pol_ == SCHED_OTHER ? PRI_FG_MAX_NP : PRI_FIFO_MAX)
1188 #define sched_get_priority_min(_pol_) \
1189 (_pol_ == SCHED_OTHER ? PRI_FG_MIN_NP : PRI_FIFO_MIN)
1190 #endif
1191
1192 int max_prio = sched_get_priority_max(policy),
1193 min_prio = sched_get_priority_min(policy),
1194 prio = m_internal->GetPriority();
1195
1196 if ( min_prio == -1 || max_prio == -1 )
1197 {
1198 wxLogError(_("Cannot get priority range for scheduling policy %d."),
1199 policy);
1200 }
1201 else if ( max_prio == min_prio )
1202 {
1203 if ( prio != WXTHREAD_DEFAULT_PRIORITY )
1204 {
1205 // notify the programmer that this doesn't work here
1206 wxLogWarning(_("Thread priority setting is ignored."));
1207 }
1208 //else: we have default priority, so don't complain
1209
1210 // anyhow, don't do anything because priority is just ignored
1211 }
1212 else
1213 {
1214 struct sched_param sp;
1215 if ( pthread_attr_getschedparam(&attr, &sp) != 0 )
1216 {
1217 wxFAIL_MSG(_T("pthread_attr_getschedparam() failed"));
1218 }
1219
1220 sp.sched_priority = min_prio + (prio*(max_prio - min_prio))/100;
1221
1222 if ( pthread_attr_setschedparam(&attr, &sp) != 0 )
1223 {
1224 wxFAIL_MSG(_T("pthread_attr_setschedparam(priority) failed"));
1225 }
1226 }
1227 #endif // HAVE_THREAD_PRIORITY_FUNCTIONS
1228
1229 #ifdef HAVE_PTHREAD_ATTR_SETSCOPE
1230 // this will make the threads created by this process really concurrent
1231 if ( pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM) != 0 )
1232 {
1233 wxFAIL_MSG(_T("pthread_attr_setscope(PTHREAD_SCOPE_SYSTEM) failed"));
1234 }
1235 #endif // HAVE_PTHREAD_ATTR_SETSCOPE
1236
1237 // VZ: assume that this one is always available (it's rather fundamental),
1238 // if this function is ever missing we should try to use
1239 // pthread_detach() instead (after thread creation)
1240 if ( m_isDetached )
1241 {
1242 if ( pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0 )
1243 {
1244 wxFAIL_MSG(_T("pthread_attr_setdetachstate(DETACHED) failed"));
1245 }
1246
1247 // never try to join detached threads
1248 m_internal->Detach();
1249 }
1250 //else: threads are created joinable by default, it's ok
1251
1252 // create the new OS thread object
1253 int rc = pthread_create
1254 (
1255 m_internal->GetIdPtr(),
1256 &attr,
1257 wxPthreadStart,
1258 (void *)this
1259 );
1260
1261 if ( pthread_attr_destroy(&attr) != 0 )
1262 {
1263 wxFAIL_MSG(_T("pthread_attr_destroy() failed"));
1264 }
1265
1266 if ( rc != 0 )
1267 {
1268 m_internal->SetState(STATE_EXITED);
1269
1270 return wxTHREAD_NO_RESOURCE;
1271 }
1272
1273 return wxTHREAD_NO_ERROR;
1274 }
1275
1276 wxThreadError wxThread::Run()
1277 {
1278 wxCriticalSectionLocker lock(m_critsect);
1279
1280 wxCHECK_MSG( m_internal->GetId(), wxTHREAD_MISC_ERROR,
1281 wxT("must call wxThread::Create() first") );
1282
1283 return m_internal->Run();
1284 }
1285
1286 // -----------------------------------------------------------------------------
1287 // misc accessors
1288 // -----------------------------------------------------------------------------
1289
1290 void wxThread::SetPriority(unsigned int prio)
1291 {
1292 wxCHECK_RET( ((int)WXTHREAD_MIN_PRIORITY <= (int)prio) &&
1293 ((int)prio <= (int)WXTHREAD_MAX_PRIORITY),
1294 wxT("invalid thread priority") );
1295
1296 wxCriticalSectionLocker lock(m_critsect);
1297
1298 switch ( m_internal->GetState() )
1299 {
1300 case STATE_NEW:
1301 // thread not yet started, priority will be set when it is
1302 m_internal->SetPriority(prio);
1303 break;
1304
1305 case STATE_RUNNING:
1306 case STATE_PAUSED:
1307 #ifdef HAVE_THREAD_PRIORITY_FUNCTIONS
1308 #if defined(__LINUX__)
1309 // On Linux, pthread_setschedparam with SCHED_OTHER does not allow
1310 // a priority other than 0. Instead, we use the BSD setpriority
1311 // which alllows us to set a 'nice' value between 20 to -20. Only
1312 // super user can set a value less than zero (more negative yields
1313 // higher priority). setpriority set the static priority of a
1314 // process, but this is OK since Linux is configured as a thread
1315 // per process.
1316 //
1317 // FIXME this is not true for 2.6!!
1318
1319 // map wx priorites WXTHREAD_MIN_PRIORITY..WXTHREAD_MAX_PRIORITY
1320 // to Unix priorities 20..-20
1321 if ( setpriority(PRIO_PROCESS, 0, -(2*(int)prio)/5 + 20) == -1 )
1322 {
1323 wxLogError(_("Failed to set thread priority %d."), prio);
1324 }
1325 #else // __LINUX__
1326 {
1327 struct sched_param sparam;
1328 sparam.sched_priority = prio;
1329
1330 if ( pthread_setschedparam(m_internal->GetId(),
1331 SCHED_OTHER, &sparam) != 0 )
1332 {
1333 wxLogError(_("Failed to set thread priority %d."), prio);
1334 }
1335 }
1336 #endif // __LINUX__
1337 #endif // HAVE_THREAD_PRIORITY_FUNCTIONS
1338 break;
1339
1340 case STATE_EXITED:
1341 default:
1342 wxFAIL_MSG(wxT("impossible to set thread priority in this state"));
1343 }
1344 }
1345
1346 unsigned int wxThread::GetPriority() const
1347 {
1348 wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect);
1349
1350 return m_internal->GetPriority();
1351 }
1352
1353 wxThreadIdType wxThread::GetId() const
1354 {
1355 return (wxThreadIdType) m_internal->GetId();
1356 }
1357
1358 // -----------------------------------------------------------------------------
1359 // pause/resume
1360 // -----------------------------------------------------------------------------
1361
1362 wxThreadError wxThread::Pause()
1363 {
1364 wxCHECK_MSG( This() != this, wxTHREAD_MISC_ERROR,
1365 _T("a thread can't pause itself") );
1366
1367 wxCriticalSectionLocker lock(m_critsect);
1368
1369 if ( m_internal->GetState() != STATE_RUNNING )
1370 {
1371 wxLogDebug(wxT("Can't pause thread which is not running."));
1372
1373 return wxTHREAD_NOT_RUNNING;
1374 }
1375
1376 // just set a flag, the thread will be really paused only during the next
1377 // call to TestDestroy()
1378 m_internal->SetState(STATE_PAUSED);
1379
1380 return wxTHREAD_NO_ERROR;
1381 }
1382
1383 wxThreadError wxThread::Resume()
1384 {
1385 wxCHECK_MSG( This() != this, wxTHREAD_MISC_ERROR,
1386 _T("a thread can't resume itself") );
1387
1388 wxCriticalSectionLocker lock(m_critsect);
1389
1390 wxThreadState state = m_internal->GetState();
1391
1392 switch ( state )
1393 {
1394 case STATE_PAUSED:
1395 wxLogTrace(TRACE_THREADS, _T("Thread %p suspended, resuming."),
1396 GetId());
1397
1398 m_internal->Resume();
1399
1400 return wxTHREAD_NO_ERROR;
1401
1402 case STATE_EXITED:
1403 wxLogTrace(TRACE_THREADS, _T("Thread %p exited, won't resume."),
1404 GetId());
1405 return wxTHREAD_NO_ERROR;
1406
1407 default:
1408 wxLogDebug(_T("Attempt to resume a thread which is not paused."));
1409
1410 return wxTHREAD_MISC_ERROR;
1411 }
1412 }
1413
1414 // -----------------------------------------------------------------------------
1415 // exiting thread
1416 // -----------------------------------------------------------------------------
1417
1418 wxThread::ExitCode wxThread::Wait()
1419 {
1420 wxCHECK_MSG( This() != this, (ExitCode)-1,
1421 _T("a thread can't wait for itself") );
1422
1423 wxCHECK_MSG( !m_isDetached, (ExitCode)-1,
1424 _T("can't wait for detached thread") );
1425
1426 m_internal->Wait();
1427
1428 return m_internal->GetExitCode();
1429 }
1430
1431 wxThreadError wxThread::Delete(ExitCode *rc)
1432 {
1433 wxCHECK_MSG( This() != this, wxTHREAD_MISC_ERROR,
1434 _T("a thread can't delete itself") );
1435
1436 bool isDetached = m_isDetached;
1437
1438 m_critsect.Enter();
1439 wxThreadState state = m_internal->GetState();
1440
1441 // ask the thread to stop
1442 m_internal->SetCancelFlag();
1443
1444 m_critsect.Leave();
1445
1446 switch ( state )
1447 {
1448 case STATE_NEW:
1449 // we need to wake up the thread so that PthreadStart() will
1450 // terminate - right now it's blocking on run semaphore in
1451 // PthreadStart()
1452 m_internal->SignalRun();
1453
1454 // fall through
1455
1456 case STATE_EXITED:
1457 // nothing to do
1458 break;
1459
1460 case STATE_PAUSED:
1461 // resume the thread first
1462 m_internal->Resume();
1463
1464 // fall through
1465
1466 default:
1467 if ( !isDetached )
1468 {
1469 // wait until the thread stops
1470 m_internal->Wait();
1471
1472 if ( rc )
1473 {
1474 // return the exit code of the thread
1475 *rc = m_internal->GetExitCode();
1476 }
1477 }
1478 //else: can't wait for detached threads
1479 }
1480
1481 return wxTHREAD_NO_ERROR;
1482 }
1483
1484 wxThreadError wxThread::Kill()
1485 {
1486 wxCHECK_MSG( This() != this, wxTHREAD_MISC_ERROR,
1487 _T("a thread can't kill itself") );
1488
1489 switch ( m_internal->GetState() )
1490 {
1491 case STATE_NEW:
1492 case STATE_EXITED:
1493 return wxTHREAD_NOT_RUNNING;
1494
1495 case STATE_PAUSED:
1496 // resume the thread first
1497 Resume();
1498
1499 // fall through
1500
1501 default:
1502 #ifdef HAVE_PTHREAD_CANCEL
1503 if ( pthread_cancel(m_internal->GetId()) != 0 )
1504 #endif // HAVE_PTHREAD_CANCEL
1505 {
1506 wxLogError(_("Failed to terminate a thread."));
1507
1508 return wxTHREAD_MISC_ERROR;
1509 }
1510
1511 #ifdef HAVE_PTHREAD_CANCEL
1512 if ( m_isDetached )
1513 {
1514 // if we use cleanup function, this will be done from
1515 // wxPthreadCleanup()
1516 #ifndef wxHAVE_PTHREAD_CLEANUP
1517 ScheduleThreadForDeletion();
1518
1519 // don't call OnExit() here, it can only be called in the
1520 // threads context and we're in the context of another thread
1521
1522 DeleteThread(this);
1523 #endif // wxHAVE_PTHREAD_CLEANUP
1524 }
1525 else
1526 {
1527 m_internal->SetExitCode(EXITCODE_CANCELLED);
1528 }
1529
1530 return wxTHREAD_NO_ERROR;
1531 #endif // HAVE_PTHREAD_CANCEL
1532 }
1533 }
1534
1535 void wxThread::Exit(ExitCode status)
1536 {
1537 wxASSERT_MSG( This() == this,
1538 _T("wxThread::Exit() can only be called in the context of the same thread") );
1539
1540 if ( m_isDetached )
1541 {
1542 // from the moment we call OnExit(), the main program may terminate at
1543 // any moment, so mark this thread as being already in process of being
1544 // deleted or wxThreadModule::OnExit() will try to delete it again
1545 ScheduleThreadForDeletion();
1546 }
1547
1548 // don't enter m_critsect before calling OnExit() because the user code
1549 // might deadlock if, for example, it signals a condition in OnExit() (a
1550 // common case) while the main thread calls any of functions entering
1551 // m_critsect on us (almost all of them do)
1552 wxTRY
1553 {
1554 OnExit();
1555 }
1556 wxCATCH_ALL( wxTheApp->OnUnhandledException(); )
1557
1558 // delete C++ thread object if this is a detached thread - user is
1559 // responsible for doing this for joinable ones
1560 if ( m_isDetached )
1561 {
1562 // FIXME I'm feeling bad about it - what if another thread function is
1563 // called (in another thread context) now? It will try to access
1564 // half destroyed object which will probably result in something
1565 // very bad - but we can't protect this by a crit section unless
1566 // we make it a global object, but this would mean that we can
1567 // only call one thread function at a time :-(
1568 DeleteThread(this);
1569 pthread_setspecific(gs_keySelf, 0);
1570 }
1571 else
1572 {
1573 m_critsect.Enter();
1574 m_internal->SetState(STATE_EXITED);
1575 m_critsect.Leave();
1576 }
1577
1578 // terminate the thread (pthread_exit() never returns)
1579 pthread_exit(status);
1580
1581 wxFAIL_MSG(_T("pthread_exit() failed"));
1582 }
1583
1584 // also test whether we were paused
1585 bool wxThread::TestDestroy()
1586 {
1587 wxASSERT_MSG( This() == this,
1588 _T("wxThread::TestDestroy() can only be called in the context of the same thread") );
1589
1590 m_critsect.Enter();
1591
1592 if ( m_internal->GetState() == STATE_PAUSED )
1593 {
1594 m_internal->SetReallyPaused(true);
1595
1596 // leave the crit section or the other threads will stop too if they
1597 // try to call any of (seemingly harmless) IsXXX() functions while we
1598 // sleep
1599 m_critsect.Leave();
1600
1601 m_internal->Pause();
1602 }
1603 else
1604 {
1605 // thread wasn't requested to pause, nothing to do
1606 m_critsect.Leave();
1607 }
1608
1609 return m_internal->WasCancelled();
1610 }
1611
1612 wxThread::~wxThread()
1613 {
1614 m_critsect.Enter();
1615
1616 // check that the thread either exited or couldn't be created
1617 if ( m_internal->GetState() != STATE_EXITED &&
1618 m_internal->GetState() != STATE_NEW )
1619 {
1620 wxLogDebug(_T("The thread %ld is being destroyed although it is still running! The application may crash."),
1621 (long)GetId());
1622 }
1623
1624 m_critsect.Leave();
1625
1626 delete m_internal;
1627
1628 // remove this thread from the global array
1629 {
1630 wxMutexLocker lock(*gs_mutexAllThreads);
1631
1632 gs_allThreads.Remove(this);
1633 }
1634 }
1635
1636 // -----------------------------------------------------------------------------
1637 // state tests
1638 // -----------------------------------------------------------------------------
1639
1640 bool wxThread::IsRunning() const
1641 {
1642 wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect);
1643
1644 return m_internal->GetState() == STATE_RUNNING;
1645 }
1646
1647 bool wxThread::IsAlive() const
1648 {
1649 wxCriticalSectionLocker lock((wxCriticalSection&)m_critsect);
1650
1651 switch ( m_internal->GetState() )
1652 {
1653 case STATE_RUNNING:
1654 case STATE_PAUSED:
1655 return true;
1656
1657 default:
1658 return false;
1659 }
1660 }
1661
1662 bool wxThread::IsPaused() const
1663 {
1664 wxCriticalSectionLocker lock((wxCriticalSection&)m_critsect);
1665
1666 return (m_internal->GetState() == STATE_PAUSED);
1667 }
1668
1669 //--------------------------------------------------------------------
1670 // wxThreadModule
1671 //--------------------------------------------------------------------
1672
1673 class wxThreadModule : public wxModule
1674 {
1675 public:
1676 virtual bool OnInit();
1677 virtual void OnExit();
1678
1679 private:
1680 DECLARE_DYNAMIC_CLASS(wxThreadModule)
1681 };
1682
1683 IMPLEMENT_DYNAMIC_CLASS(wxThreadModule, wxModule)
1684
1685 bool wxThreadModule::OnInit()
1686 {
1687 int rc = pthread_key_create(&gs_keySelf, NULL /* dtor function */);
1688 if ( rc != 0 )
1689 {
1690 wxLogSysError(rc, _("Thread module initialization failed: failed to create thread key"));
1691
1692 return false;
1693 }
1694
1695 wxThread::ms_idMainThread = wxThread::GetCurrentId();
1696
1697 gs_mutexAllThreads = new wxMutex();
1698
1699 gs_mutexGui = new wxMutex();
1700 gs_mutexGui->Lock();
1701
1702 gs_mutexDeleteThread = new wxMutex();
1703 gs_condAllDeleted = new wxCondition(*gs_mutexDeleteThread);
1704
1705 return true;
1706 }
1707
1708 void wxThreadModule::OnExit()
1709 {
1710 wxASSERT_MSG( wxThread::IsMain(), wxT("only main thread can be here") );
1711
1712 // are there any threads left which are being deleted right now?
1713 size_t nThreadsBeingDeleted;
1714
1715 {
1716 wxMutexLocker lock( *gs_mutexDeleteThread );
1717 nThreadsBeingDeleted = gs_nThreadsBeingDeleted;
1718
1719 if ( nThreadsBeingDeleted > 0 )
1720 {
1721 wxLogTrace(TRACE_THREADS,
1722 _T("Waiting for %lu threads to disappear"),
1723 (unsigned long)nThreadsBeingDeleted);
1724
1725 // have to wait until all of them disappear
1726 gs_condAllDeleted->Wait();
1727 }
1728 }
1729
1730 size_t count;
1731
1732 {
1733 wxMutexLocker lock(*gs_mutexAllThreads);
1734
1735 // terminate any threads left
1736 count = gs_allThreads.GetCount();
1737 if ( count != 0u )
1738 {
1739 wxLogDebug(wxT("%lu threads were not terminated by the application."),
1740 (unsigned long)count);
1741 }
1742 } // unlock mutex before deleting the threads as they lock it in their dtor
1743
1744 for ( size_t n = 0u; n < count; n++ )
1745 {
1746 // Delete calls the destructor which removes the current entry. We
1747 // should only delete the first one each time.
1748 gs_allThreads[0]->Delete();
1749 }
1750
1751 delete gs_mutexAllThreads;
1752
1753 // destroy GUI mutex
1754 gs_mutexGui->Unlock();
1755 delete gs_mutexGui;
1756
1757 // and free TLD slot
1758 (void)pthread_key_delete(gs_keySelf);
1759
1760 delete gs_condAllDeleted;
1761 delete gs_mutexDeleteThread;
1762 }
1763
1764 // ----------------------------------------------------------------------------
1765 // global functions
1766 // ----------------------------------------------------------------------------
1767
1768 static void ScheduleThreadForDeletion()
1769 {
1770 wxMutexLocker lock( *gs_mutexDeleteThread );
1771
1772 gs_nThreadsBeingDeleted++;
1773
1774 wxLogTrace(TRACE_THREADS, _T("%lu thread%s waiting to be deleted"),
1775 (unsigned long)gs_nThreadsBeingDeleted,
1776 gs_nThreadsBeingDeleted == 1 ? _T("") : _T("s"));
1777 }
1778
1779 static void DeleteThread(wxThread *This)
1780 {
1781 // gs_mutexDeleteThread should be unlocked before signalling the condition
1782 // or wxThreadModule::OnExit() would deadlock
1783 wxMutexLocker locker( *gs_mutexDeleteThread );
1784
1785 wxLogTrace(TRACE_THREADS, _T("Thread %p auto deletes."), This->GetId());
1786
1787 delete This;
1788
1789 wxCHECK_RET( gs_nThreadsBeingDeleted > 0,
1790 _T("no threads scheduled for deletion, yet we delete one?") );
1791
1792 wxLogTrace(TRACE_THREADS, _T("%lu threads remain scheduled for deletion."),
1793 (unsigned long)gs_nThreadsBeingDeleted - 1);
1794
1795 if ( !--gs_nThreadsBeingDeleted )
1796 {
1797 // no more threads left, signal it
1798 gs_condAllDeleted->Signal();
1799 }
1800 }
1801
1802 void wxMutexGuiEnterImpl()
1803 {
1804 gs_mutexGui->Lock();
1805 }
1806
1807 void wxMutexGuiLeaveImpl()
1808 {
1809 gs_mutexGui->Unlock();
1810 }
1811
1812 // ----------------------------------------------------------------------------
1813 // include common implementation code
1814 // ----------------------------------------------------------------------------
1815
1816 #include "wx/thrimpl.cpp"
1817
1818 #endif // wxUSE_THREADS