]>
Commit | Line | Data |
---|---|---|
1 | ///////////////////////////////////////////////////////////////////////////// | |
2 | // Name: src/msw/thread.cpp | |
3 | // Purpose: wxThread Implementation | |
4 | // Author: Original from Wolfram Gloger/Guilhem Lavaux | |
5 | // Modified by: Vadim Zeitlin to make it work :-) | |
6 | // Created: 04/22/98 | |
7 | // RCS-ID: $Id$ | |
8 | // Copyright: (c) Wolfram Gloger (1996, 1997), Guilhem Lavaux (1998); | |
9 | // Vadim Zeitlin (1999-2002) | |
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 defined(__BORLANDC__) | |
25 | #pragma hdrstop | |
26 | #endif | |
27 | ||
28 | #ifndef WX_PRECOMP | |
29 | # include "wx/wx.h" | |
30 | #endif | |
31 | ||
32 | #if wxUSE_THREADS | |
33 | ||
34 | #include "wx/msw/private.h" | |
35 | #include "wx/msw/missing.h" | |
36 | ||
37 | #include "wx/module.h" | |
38 | #include "wx/thread.h" | |
39 | ||
40 | // must have this symbol defined to get _beginthread/_endthread declarations | |
41 | #ifndef _MT | |
42 | #define _MT | |
43 | #endif | |
44 | ||
45 | #if defined(__BORLANDC__) | |
46 | #if !defined(__MT__) | |
47 | // I can't set -tWM in the IDE (anyone?) so have to do this | |
48 | #define __MT__ | |
49 | #endif | |
50 | ||
51 | #if !defined(__MFC_COMPAT__) | |
52 | // Needed to know about _beginthreadex etc.. | |
53 | #define __MFC_COMPAT__ | |
54 | #endif | |
55 | #endif // BC++ | |
56 | ||
57 | // define wxUSE_BEGIN_THREAD if the compiler has _beginthreadex() function | |
58 | // which should be used instead of Win32 ::CreateThread() if possible | |
59 | #if defined(__VISUALC__) || \ | |
60 | (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \ | |
61 | (defined(__GNUG__) && defined(__MSVCRT__)) || \ | |
62 | defined(__WATCOMC__) || defined(__MWERKS__) | |
63 | ||
64 | #undef wxUSE_BEGIN_THREAD | |
65 | #define wxUSE_BEGIN_THREAD | |
66 | #endif | |
67 | ||
68 | #ifdef wxUSE_BEGIN_THREAD | |
69 | // this is where _beginthreadex() is declared | |
70 | #include <process.h> | |
71 | ||
72 | // the return type of the thread function entry point | |
73 | typedef unsigned THREAD_RETVAL; | |
74 | ||
75 | // the calling convention of the thread function entry point | |
76 | #define THREAD_CALLCONV __stdcall | |
77 | #else | |
78 | // the settings for CreateThread() | |
79 | typedef DWORD THREAD_RETVAL; | |
80 | #define THREAD_CALLCONV WINAPI | |
81 | #endif | |
82 | ||
83 | // ---------------------------------------------------------------------------- | |
84 | // constants | |
85 | // ---------------------------------------------------------------------------- | |
86 | ||
87 | // the possible states of the thread ("=>" shows all possible transitions from | |
88 | // this state) | |
89 | enum wxThreadState | |
90 | { | |
91 | STATE_NEW, // didn't start execution yet (=> RUNNING) | |
92 | STATE_RUNNING, // thread is running (=> PAUSED, CANCELED) | |
93 | STATE_PAUSED, // thread is temporarily suspended (=> RUNNING) | |
94 | STATE_CANCELED, // thread should terminate a.s.a.p. (=> EXITED) | |
95 | STATE_EXITED // thread is terminating | |
96 | }; | |
97 | ||
98 | // ---------------------------------------------------------------------------- | |
99 | // this module globals | |
100 | // ---------------------------------------------------------------------------- | |
101 | ||
102 | // TLS index of the slot where we store the pointer to the current thread | |
103 | static DWORD gs_tlsThisThread = 0xFFFFFFFF; | |
104 | ||
105 | // id of the main thread - the one which can call GUI functions without first | |
106 | // calling wxMutexGuiEnter() | |
107 | static DWORD gs_idMainThread = 0; | |
108 | ||
109 | // if it's FALSE, some secondary thread is holding the GUI lock | |
110 | static bool gs_bGuiOwnedByMainThread = TRUE; | |
111 | ||
112 | // critical section which controls access to all GUI functions: any secondary | |
113 | // thread (i.e. except the main one) must enter this crit section before doing | |
114 | // any GUI calls | |
115 | static wxCriticalSection *gs_critsectGui = NULL; | |
116 | ||
117 | // critical section which protects gs_nWaitingForGui variable | |
118 | static wxCriticalSection *gs_critsectWaitingForGui = NULL; | |
119 | ||
120 | // number of threads waiting for GUI in wxMutexGuiEnter() | |
121 | static size_t gs_nWaitingForGui = 0; | |
122 | ||
123 | // are we waiting for a thread termination? | |
124 | static bool gs_waitingForThread = FALSE; | |
125 | ||
126 | // ============================================================================ | |
127 | // Windows implementation of thread and related classes | |
128 | // ============================================================================ | |
129 | ||
130 | // ---------------------------------------------------------------------------- | |
131 | // wxCriticalSection | |
132 | // ---------------------------------------------------------------------------- | |
133 | ||
134 | wxCriticalSection::wxCriticalSection() | |
135 | { | |
136 | wxCOMPILE_TIME_ASSERT( sizeof(CRITICAL_SECTION) <= sizeof(wxCritSectBuffer), | |
137 | wxCriticalSectionBufferTooSmall ); | |
138 | ||
139 | ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer); | |
140 | } | |
141 | ||
142 | wxCriticalSection::~wxCriticalSection() | |
143 | { | |
144 | ::DeleteCriticalSection((CRITICAL_SECTION *)m_buffer); | |
145 | } | |
146 | ||
147 | void wxCriticalSection::Enter() | |
148 | { | |
149 | ::EnterCriticalSection((CRITICAL_SECTION *)m_buffer); | |
150 | } | |
151 | ||
152 | void wxCriticalSection::Leave() | |
153 | { | |
154 | ::LeaveCriticalSection((CRITICAL_SECTION *)m_buffer); | |
155 | } | |
156 | ||
157 | // ---------------------------------------------------------------------------- | |
158 | // wxMutex | |
159 | // ---------------------------------------------------------------------------- | |
160 | ||
161 | class wxMutexInternal | |
162 | { | |
163 | public: | |
164 | wxMutexInternal(wxMutexType mutexType); | |
165 | ~wxMutexInternal(); | |
166 | ||
167 | bool IsOk() const { return m_mutex != NULL; } | |
168 | ||
169 | wxMutexError Lock() { return LockTimeout(INFINITE); } | |
170 | wxMutexError TryLock() { return LockTimeout(0); } | |
171 | wxMutexError Unlock(); | |
172 | ||
173 | private: | |
174 | wxMutexError LockTimeout(DWORD milliseconds); | |
175 | ||
176 | HANDLE m_mutex; | |
177 | ||
178 | DECLARE_NO_COPY_CLASS(wxMutexInternal) | |
179 | }; | |
180 | ||
181 | // all mutexes are recursive under Win32 so we don't use mutexType | |
182 | wxMutexInternal::wxMutexInternal(wxMutexType WXUNUSED(mutexType)) | |
183 | { | |
184 | // create a nameless (hence intra process and always private) mutex | |
185 | m_mutex = ::CreateMutex | |
186 | ( | |
187 | NULL, // default secutiry attributes | |
188 | FALSE, // not initially locked | |
189 | NULL // no name | |
190 | ); | |
191 | ||
192 | if ( !m_mutex ) | |
193 | { | |
194 | wxLogLastError(_T("CreateMutex()")); | |
195 | } | |
196 | } | |
197 | ||
198 | wxMutexInternal::~wxMutexInternal() | |
199 | { | |
200 | if ( m_mutex ) | |
201 | { | |
202 | if ( !::CloseHandle(m_mutex) ) | |
203 | { | |
204 | wxLogLastError(_T("CloseHandle(mutex)")); | |
205 | } | |
206 | } | |
207 | } | |
208 | ||
209 | wxMutexError wxMutexInternal::LockTimeout(DWORD milliseconds) | |
210 | { | |
211 | DWORD rc = ::WaitForSingleObject(m_mutex, milliseconds); | |
212 | if ( rc == WAIT_ABANDONED ) | |
213 | { | |
214 | // the previous caller died without releasing the mutex, but now we can | |
215 | // really lock it | |
216 | wxLogDebug(_T("WaitForSingleObject() returned WAIT_ABANDONED")); | |
217 | ||
218 | // use 0 timeout, normally we should always get it | |
219 | rc = ::WaitForSingleObject(m_mutex, 0); | |
220 | } | |
221 | ||
222 | switch ( rc ) | |
223 | { | |
224 | case WAIT_OBJECT_0: | |
225 | // ok | |
226 | break; | |
227 | ||
228 | case WAIT_TIMEOUT: | |
229 | return wxMUTEX_BUSY; | |
230 | ||
231 | case WAIT_ABANDONED: // checked for above | |
232 | default: | |
233 | wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock")); | |
234 | // fall through | |
235 | ||
236 | case WAIT_FAILED: | |
237 | wxLogLastError(_T("WaitForSingleObject(mutex)")); | |
238 | return wxMUTEX_MISC_ERROR; | |
239 | } | |
240 | ||
241 | return wxMUTEX_NO_ERROR; | |
242 | } | |
243 | ||
244 | wxMutexError wxMutexInternal::Unlock() | |
245 | { | |
246 | if ( !::ReleaseMutex(m_mutex) ) | |
247 | { | |
248 | wxLogLastError(_T("ReleaseMutex()")); | |
249 | ||
250 | return wxMUTEX_MISC_ERROR; | |
251 | } | |
252 | ||
253 | return wxMUTEX_NO_ERROR; | |
254 | } | |
255 | ||
256 | // -------------------------------------------------------------------------- | |
257 | // wxSemaphore | |
258 | // -------------------------------------------------------------------------- | |
259 | ||
260 | // a trivial wrapper around Win32 semaphore | |
261 | class wxSemaphoreInternal | |
262 | { | |
263 | public: | |
264 | wxSemaphoreInternal(int initialcount, int maxcount); | |
265 | ~wxSemaphoreInternal(); | |
266 | ||
267 | bool IsOk() const { return m_semaphore != NULL; } | |
268 | ||
269 | wxSemaError Wait() { return WaitTimeout(INFINITE); } | |
270 | wxSemaError TryWait() { return WaitTimeout(0); } | |
271 | wxSemaError WaitTimeout(unsigned long milliseconds); | |
272 | ||
273 | wxSemaError Post(); | |
274 | ||
275 | private: | |
276 | HANDLE m_semaphore; | |
277 | ||
278 | DECLARE_NO_COPY_CLASS(wxSemaphoreInternal) | |
279 | }; | |
280 | ||
281 | wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount) | |
282 | { | |
283 | if ( maxcount == 0 ) | |
284 | { | |
285 | // make it practically infinite | |
286 | maxcount = INT_MAX; | |
287 | } | |
288 | ||
289 | m_semaphore = ::CreateSemaphore | |
290 | ( | |
291 | NULL, // default security attributes | |
292 | initialcount, | |
293 | maxcount, | |
294 | NULL // no name | |
295 | ); | |
296 | ||
297 | if ( !m_semaphore ) | |
298 | { | |
299 | wxLogLastError(_T("CreateSemaphore()")); | |
300 | } | |
301 | } | |
302 | ||
303 | wxSemaphoreInternal::~wxSemaphoreInternal() | |
304 | { | |
305 | if ( m_semaphore ) | |
306 | { | |
307 | if ( !::CloseHandle(m_semaphore) ) | |
308 | { | |
309 | wxLogLastError(_T("CloseHandle(semaphore)")); | |
310 | } | |
311 | } | |
312 | } | |
313 | ||
314 | wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long milliseconds) | |
315 | { | |
316 | DWORD rc = ::WaitForSingleObject( m_semaphore, milliseconds ); | |
317 | ||
318 | switch ( rc ) | |
319 | { | |
320 | case WAIT_OBJECT_0: | |
321 | return wxSEMA_NO_ERROR; | |
322 | ||
323 | case WAIT_TIMEOUT: | |
324 | return wxSEMA_BUSY; | |
325 | ||
326 | default: | |
327 | wxLogLastError(_T("WaitForSingleObject(semaphore)")); | |
328 | } | |
329 | ||
330 | return wxSEMA_MISC_ERROR; | |
331 | } | |
332 | ||
333 | wxSemaError wxSemaphoreInternal::Post() | |
334 | { | |
335 | if ( !::ReleaseSemaphore(m_semaphore, 1, NULL /* ptr to previous count */) ) | |
336 | { | |
337 | wxLogLastError(_T("ReleaseSemaphore")); | |
338 | ||
339 | return wxSEMA_MISC_ERROR; | |
340 | } | |
341 | ||
342 | return wxSEMA_NO_ERROR; | |
343 | } | |
344 | ||
345 | // -------------------------------------------------------------------------- | |
346 | // wxCondition | |
347 | // -------------------------------------------------------------------------- | |
348 | ||
349 | // Win32 doesn't have explicit support for the POSIX condition variables and | |
350 | // the Win32 events have quite different semantics, so we reimplement the | |
351 | // conditions from scratch using the mutexes and semaphores | |
352 | class wxConditionInternal | |
353 | { | |
354 | public: | |
355 | wxConditionInternal(wxMutex& mutex); | |
356 | ||
357 | bool IsOk() const { return m_mutex.IsOk() && m_semaphore.IsOk(); } | |
358 | ||
359 | wxCondError Wait(); | |
360 | wxCondError WaitTimeout(unsigned long milliseconds); | |
361 | ||
362 | wxCondError Signal(); | |
363 | wxCondError Broadcast(); | |
364 | ||
365 | private: | |
366 | // the number of threads currently waiting for this condition | |
367 | LONG m_numWaiters; | |
368 | ||
369 | // the critical section protecting m_numWaiters | |
370 | wxCriticalSection m_csWaiters; | |
371 | ||
372 | wxMutex& m_mutex; | |
373 | wxSemaphore m_semaphore; | |
374 | }; | |
375 | ||
376 | wxConditionInternal::wxConditionInternal(wxMutex& mutex) | |
377 | : m_mutex(mutex) | |
378 | { | |
379 | // another thread can't access it until we return from ctor, so no need to | |
380 | // protect access to m_numWaiters here | |
381 | m_numWaiters = 0; | |
382 | } | |
383 | ||
384 | wxCondError wxConditionInternal::Wait() | |
385 | { | |
386 | // increment the number of waiters | |
387 | ::InterlockedIncrement(&m_numWaiters); | |
388 | ||
389 | m_mutex.Unlock(); | |
390 | ||
391 | // a potential race condition can occur here | |
392 | // | |
393 | // after a thread increments nwaiters, and unlocks the mutex and before the | |
394 | // semaphore.Wait() is called, if another thread can cause a signal to be | |
395 | // generated | |
396 | // | |
397 | // this race condition is handled by using a semaphore and incrementing the | |
398 | // semaphore only if 'nwaiters' is greater that zero since the semaphore, | |
399 | // can 'remember' signals the race condition will not occur | |
400 | ||
401 | // wait ( if necessary ) and decrement semaphore | |
402 | wxSemaError err = m_semaphore.Wait(); | |
403 | m_mutex.Lock(); | |
404 | ||
405 | return err == wxSEMA_NO_ERROR ? wxCOND_NO_ERROR : wxCOND_MISC_ERROR; | |
406 | } | |
407 | ||
408 | wxCondError wxConditionInternal::WaitTimeout(unsigned long milliseconds) | |
409 | { | |
410 | ::InterlockedIncrement(&m_numWaiters); | |
411 | ||
412 | m_mutex.Unlock(); | |
413 | ||
414 | // a race condition can occur at this point in the code | |
415 | // | |
416 | // please see the comments in Wait(), for details | |
417 | ||
418 | wxSemaError err = m_semaphore.WaitTimeout(milliseconds); | |
419 | ||
420 | if ( err == wxSEMA_BUSY ) | |
421 | { | |
422 | // another potential race condition exists here it is caused when a | |
423 | // 'waiting' thread timesout, and returns from WaitForSingleObject, but | |
424 | // has not yet decremented 'nwaiters'. | |
425 | // | |
426 | // at this point if another thread calls signal() then the semaphore | |
427 | // will be incremented, but the waiting thread will miss it. | |
428 | // | |
429 | // to handle this particular case, the waiting thread calls | |
430 | // WaitForSingleObject again with a timeout of 0, after locking | |
431 | // 'nwaiters_mutex'. this call does not block because of the zero | |
432 | // timeout, but will allow the waiting thread to catch the missed | |
433 | // signals. | |
434 | wxCriticalSectionLocker lock(m_csWaiters); | |
435 | ||
436 | err = m_semaphore.WaitTimeout(0); | |
437 | ||
438 | if ( err != wxSEMA_NO_ERROR ) | |
439 | { | |
440 | m_numWaiters--; | |
441 | } | |
442 | } | |
443 | ||
444 | m_mutex.Lock(); | |
445 | ||
446 | return err == wxSEMA_NO_ERROR ? wxCOND_NO_ERROR : wxCOND_MISC_ERROR; | |
447 | } | |
448 | ||
449 | wxCondError wxConditionInternal::Signal() | |
450 | { | |
451 | wxCriticalSectionLocker lock(m_csWaiters); | |
452 | ||
453 | if ( m_numWaiters > 0 ) | |
454 | { | |
455 | // increment the semaphore by 1 | |
456 | if ( m_semaphore.Post() != wxSEMA_NO_ERROR ) | |
457 | return wxCOND_MISC_ERROR; | |
458 | ||
459 | m_numWaiters--; | |
460 | } | |
461 | ||
462 | return wxCOND_NO_ERROR; | |
463 | } | |
464 | ||
465 | wxCondError wxConditionInternal::Broadcast() | |
466 | { | |
467 | wxCriticalSectionLocker lock(m_csWaiters); | |
468 | ||
469 | while ( m_numWaiters > 0 ) | |
470 | { | |
471 | if ( m_semaphore.Post() != wxSEMA_NO_ERROR ) | |
472 | return wxCOND_MISC_ERROR; | |
473 | ||
474 | m_numWaiters--; | |
475 | } | |
476 | ||
477 | return wxCOND_NO_ERROR; | |
478 | } | |
479 | ||
480 | // ---------------------------------------------------------------------------- | |
481 | // wxThread implementation | |
482 | // ---------------------------------------------------------------------------- | |
483 | ||
484 | // wxThreadInternal class | |
485 | // ---------------------- | |
486 | ||
487 | class wxThreadInternal | |
488 | { | |
489 | public: | |
490 | wxThreadInternal() | |
491 | { | |
492 | m_hThread = 0; | |
493 | m_state = STATE_NEW; | |
494 | m_priority = WXTHREAD_DEFAULT_PRIORITY; | |
495 | } | |
496 | ||
497 | ~wxThreadInternal() | |
498 | { | |
499 | Free(); | |
500 | } | |
501 | ||
502 | void Free() | |
503 | { | |
504 | if ( m_hThread ) | |
505 | { | |
506 | if ( !::CloseHandle(m_hThread) ) | |
507 | { | |
508 | wxLogLastError(wxT("CloseHandle(thread)")); | |
509 | } | |
510 | ||
511 | m_hThread = 0; | |
512 | } | |
513 | } | |
514 | ||
515 | // create a new (suspended) thread (for the given thread object) | |
516 | bool Create(wxThread *thread, unsigned int stackSize); | |
517 | ||
518 | // suspend/resume/terminate | |
519 | bool Suspend(); | |
520 | bool Resume(); | |
521 | void Cancel() { m_state = STATE_CANCELED; } | |
522 | ||
523 | // thread state | |
524 | void SetState(wxThreadState state) { m_state = state; } | |
525 | wxThreadState GetState() const { return m_state; } | |
526 | ||
527 | // thread priority | |
528 | void SetPriority(unsigned int priority); | |
529 | unsigned int GetPriority() const { return m_priority; } | |
530 | ||
531 | // thread handle and id | |
532 | HANDLE GetHandle() const { return m_hThread; } | |
533 | DWORD GetId() const { return m_tid; } | |
534 | ||
535 | // thread function | |
536 | static THREAD_RETVAL THREAD_CALLCONV WinThreadStart(void *thread); | |
537 | ||
538 | private: | |
539 | HANDLE m_hThread; // handle of the thread | |
540 | wxThreadState m_state; // state, see wxThreadState enum | |
541 | unsigned int m_priority; // thread priority in "wx" units | |
542 | DWORD m_tid; // thread id | |
543 | ||
544 | DECLARE_NO_COPY_CLASS(wxThreadInternal) | |
545 | }; | |
546 | ||
547 | THREAD_RETVAL THREAD_CALLCONV wxThreadInternal::WinThreadStart(void *param) | |
548 | { | |
549 | THREAD_RETVAL rc; | |
550 | bool wasCancelled; | |
551 | ||
552 | // first of all, check whether we hadn't been cancelled already and don't | |
553 | // start the user code at all then | |
554 | wxThread *thread = (wxThread *)param; | |
555 | if ( thread->m_internal->GetState() == STATE_EXITED ) | |
556 | { | |
557 | rc = (THREAD_RETVAL)-1; | |
558 | wasCancelled = TRUE; | |
559 | } | |
560 | else // do run thread | |
561 | { | |
562 | // store the thread object in the TLS | |
563 | if ( !::TlsSetValue(gs_tlsThisThread, thread) ) | |
564 | { | |
565 | wxLogSysError(_("Can not start thread: error writing TLS.")); | |
566 | ||
567 | return (DWORD)-1; | |
568 | } | |
569 | ||
570 | rc = (THREAD_RETVAL)thread->Entry(); | |
571 | ||
572 | // enter m_critsect before changing the thread state | |
573 | thread->m_critsect.Enter(); | |
574 | wasCancelled = thread->m_internal->GetState() == STATE_CANCELED; | |
575 | thread->m_internal->SetState(STATE_EXITED); | |
576 | thread->m_critsect.Leave(); | |
577 | } | |
578 | ||
579 | thread->OnExit(); | |
580 | ||
581 | // if the thread was cancelled (from Delete()), then its handle is still | |
582 | // needed there | |
583 | if ( thread->IsDetached() && !wasCancelled ) | |
584 | { | |
585 | // auto delete | |
586 | delete thread; | |
587 | } | |
588 | //else: the joinable threads handle will be closed when Wait() is done | |
589 | ||
590 | return rc; | |
591 | } | |
592 | ||
593 | void wxThreadInternal::SetPriority(unsigned int priority) | |
594 | { | |
595 | m_priority = priority; | |
596 | ||
597 | // translate wxWindows priority to the Windows one | |
598 | int win_priority; | |
599 | if (m_priority <= 20) | |
600 | win_priority = THREAD_PRIORITY_LOWEST; | |
601 | else if (m_priority <= 40) | |
602 | win_priority = THREAD_PRIORITY_BELOW_NORMAL; | |
603 | else if (m_priority <= 60) | |
604 | win_priority = THREAD_PRIORITY_NORMAL; | |
605 | else if (m_priority <= 80) | |
606 | win_priority = THREAD_PRIORITY_ABOVE_NORMAL; | |
607 | else if (m_priority <= 100) | |
608 | win_priority = THREAD_PRIORITY_HIGHEST; | |
609 | else | |
610 | { | |
611 | wxFAIL_MSG(wxT("invalid value of thread priority parameter")); | |
612 | win_priority = THREAD_PRIORITY_NORMAL; | |
613 | } | |
614 | ||
615 | if ( !::SetThreadPriority(m_hThread, win_priority) ) | |
616 | { | |
617 | wxLogSysError(_("Can't set thread priority")); | |
618 | } | |
619 | } | |
620 | ||
621 | bool wxThreadInternal::Create(wxThread *thread, unsigned int stackSize) | |
622 | { | |
623 | // for compilers which have it, we should use C RTL function for thread | |
624 | // creation instead of Win32 API one because otherwise we will have memory | |
625 | // leaks if the thread uses C RTL (and most threads do) | |
626 | #ifdef wxUSE_BEGIN_THREAD | |
627 | ||
628 | // Watcom is reported to not like 0 stack size (which means "use default" | |
629 | // for the other compilers and is also the default value for stackSize) | |
630 | #ifdef __WATCOMC__ | |
631 | if ( !stackSize ) | |
632 | stackSize = 10240; | |
633 | #endif // __WATCOMC__ | |
634 | ||
635 | m_hThread = (HANDLE)_beginthreadex | |
636 | ( | |
637 | NULL, // default security | |
638 | stackSize, | |
639 | wxThreadInternal::WinThreadStart, // entry point | |
640 | thread, | |
641 | CREATE_SUSPENDED, | |
642 | (unsigned int *)&m_tid | |
643 | ); | |
644 | #else // compiler doesn't have _beginthreadex | |
645 | m_hThread = ::CreateThread | |
646 | ( | |
647 | NULL, // default security | |
648 | stackSize, // stack size | |
649 | wxThreadInternal::WinThreadStart, // thread entry point | |
650 | (LPVOID)thread, // parameter | |
651 | CREATE_SUSPENDED, // flags | |
652 | &m_tid // [out] thread id | |
653 | ); | |
654 | #endif // _beginthreadex/CreateThread | |
655 | ||
656 | if ( m_hThread == NULL ) | |
657 | { | |
658 | wxLogSysError(_("Can't create thread")); | |
659 | ||
660 | return FALSE; | |
661 | } | |
662 | ||
663 | if ( m_priority != WXTHREAD_DEFAULT_PRIORITY ) | |
664 | { | |
665 | SetPriority(m_priority); | |
666 | } | |
667 | ||
668 | return TRUE; | |
669 | } | |
670 | ||
671 | bool wxThreadInternal::Suspend() | |
672 | { | |
673 | DWORD nSuspendCount = ::SuspendThread(m_hThread); | |
674 | if ( nSuspendCount == (DWORD)-1 ) | |
675 | { | |
676 | wxLogSysError(_("Can not suspend thread %x"), m_hThread); | |
677 | ||
678 | return FALSE; | |
679 | } | |
680 | ||
681 | m_state = STATE_PAUSED; | |
682 | ||
683 | return TRUE; | |
684 | } | |
685 | ||
686 | bool wxThreadInternal::Resume() | |
687 | { | |
688 | DWORD nSuspendCount = ::ResumeThread(m_hThread); | |
689 | if ( nSuspendCount == (DWORD)-1 ) | |
690 | { | |
691 | wxLogSysError(_("Can not resume thread %x"), m_hThread); | |
692 | ||
693 | return FALSE; | |
694 | } | |
695 | ||
696 | // don't change the state from STATE_EXITED because it's special and means | |
697 | // we are going to terminate without running any user code - if we did it, | |
698 | // the codei n Delete() wouldn't work | |
699 | if ( m_state != STATE_EXITED ) | |
700 | { | |
701 | m_state = STATE_RUNNING; | |
702 | } | |
703 | ||
704 | return TRUE; | |
705 | } | |
706 | ||
707 | // static functions | |
708 | // ---------------- | |
709 | ||
710 | wxThread *wxThread::This() | |
711 | { | |
712 | wxThread *thread = (wxThread *)::TlsGetValue(gs_tlsThisThread); | |
713 | ||
714 | // be careful, 0 may be a valid return value as well | |
715 | if ( !thread && (::GetLastError() != NO_ERROR) ) | |
716 | { | |
717 | wxLogSysError(_("Couldn't get the current thread pointer")); | |
718 | ||
719 | // return NULL... | |
720 | } | |
721 | ||
722 | return thread; | |
723 | } | |
724 | ||
725 | bool wxThread::IsMain() | |
726 | { | |
727 | return ::GetCurrentThreadId() == gs_idMainThread; | |
728 | } | |
729 | ||
730 | #ifdef Yield | |
731 | #undef Yield | |
732 | #endif | |
733 | ||
734 | void wxThread::Yield() | |
735 | { | |
736 | // 0 argument to Sleep() is special and means to just give away the rest of | |
737 | // our timeslice | |
738 | ::Sleep(0); | |
739 | } | |
740 | ||
741 | void wxThread::Sleep(unsigned long milliseconds) | |
742 | { | |
743 | ::Sleep(milliseconds); | |
744 | } | |
745 | ||
746 | int wxThread::GetCPUCount() | |
747 | { | |
748 | SYSTEM_INFO si; | |
749 | GetSystemInfo(&si); | |
750 | ||
751 | return si.dwNumberOfProcessors; | |
752 | } | |
753 | ||
754 | unsigned long wxThread::GetCurrentId() | |
755 | { | |
756 | return (unsigned long)::GetCurrentThreadId(); | |
757 | } | |
758 | ||
759 | bool wxThread::SetConcurrency(size_t level) | |
760 | { | |
761 | wxASSERT_MSG( IsMain(), _T("should only be called from the main thread") ); | |
762 | ||
763 | // ok only for the default one | |
764 | if ( level == 0 ) | |
765 | return 0; | |
766 | ||
767 | // get system affinity mask first | |
768 | HANDLE hProcess = ::GetCurrentProcess(); | |
769 | DWORD dwProcMask, dwSysMask; | |
770 | if ( ::GetProcessAffinityMask(hProcess, &dwProcMask, &dwSysMask) == 0 ) | |
771 | { | |
772 | wxLogLastError(_T("GetProcessAffinityMask")); | |
773 | ||
774 | return FALSE; | |
775 | } | |
776 | ||
777 | // how many CPUs have we got? | |
778 | if ( dwSysMask == 1 ) | |
779 | { | |
780 | // don't bother with all this complicated stuff - on a single | |
781 | // processor system it doesn't make much sense anyhow | |
782 | return level == 1; | |
783 | } | |
784 | ||
785 | // calculate the process mask: it's a bit vector with one bit per | |
786 | // processor; we want to schedule the process to run on first level | |
787 | // CPUs | |
788 | DWORD bit = 1; | |
789 | while ( bit ) | |
790 | { | |
791 | if ( dwSysMask & bit ) | |
792 | { | |
793 | // ok, we can set this bit | |
794 | dwProcMask |= bit; | |
795 | ||
796 | // another process added | |
797 | if ( !--level ) | |
798 | { | |
799 | // and that's enough | |
800 | break; | |
801 | } | |
802 | } | |
803 | ||
804 | // next bit | |
805 | bit <<= 1; | |
806 | } | |
807 | ||
808 | // could we set all bits? | |
809 | if ( level != 0 ) | |
810 | { | |
811 | wxLogDebug(_T("bad level %u in wxThread::SetConcurrency()"), level); | |
812 | ||
813 | return FALSE; | |
814 | } | |
815 | ||
816 | // set it: we can't link to SetProcessAffinityMask() because it doesn't | |
817 | // exist in Win9x, use RT binding instead | |
818 | ||
819 | typedef BOOL (*SETPROCESSAFFINITYMASK)(HANDLE, DWORD); | |
820 | ||
821 | // can use static var because we're always in the main thread here | |
822 | static SETPROCESSAFFINITYMASK pfnSetProcessAffinityMask = NULL; | |
823 | ||
824 | if ( !pfnSetProcessAffinityMask ) | |
825 | { | |
826 | HMODULE hModKernel = ::LoadLibrary(_T("kernel32")); | |
827 | if ( hModKernel ) | |
828 | { | |
829 | pfnSetProcessAffinityMask = (SETPROCESSAFFINITYMASK) | |
830 | ::GetProcAddress(hModKernel, "SetProcessAffinityMask"); | |
831 | } | |
832 | ||
833 | // we've discovered a MT version of Win9x! | |
834 | wxASSERT_MSG( pfnSetProcessAffinityMask, | |
835 | _T("this system has several CPUs but no SetProcessAffinityMask function?") ); | |
836 | } | |
837 | ||
838 | if ( !pfnSetProcessAffinityMask ) | |
839 | { | |
840 | // msg given above - do it only once | |
841 | return FALSE; | |
842 | } | |
843 | ||
844 | if ( pfnSetProcessAffinityMask(hProcess, dwProcMask) == 0 ) | |
845 | { | |
846 | wxLogLastError(_T("SetProcessAffinityMask")); | |
847 | ||
848 | return FALSE; | |
849 | } | |
850 | ||
851 | return TRUE; | |
852 | } | |
853 | ||
854 | // ctor and dtor | |
855 | // ------------- | |
856 | ||
857 | wxThread::wxThread(wxThreadKind kind) | |
858 | { | |
859 | m_internal = new wxThreadInternal(); | |
860 | ||
861 | m_isDetached = kind == wxTHREAD_DETACHED; | |
862 | } | |
863 | ||
864 | wxThread::~wxThread() | |
865 | { | |
866 | delete m_internal; | |
867 | } | |
868 | ||
869 | // create/start thread | |
870 | // ------------------- | |
871 | ||
872 | wxThreadError wxThread::Create(unsigned int stackSize) | |
873 | { | |
874 | wxCriticalSectionLocker lock(m_critsect); | |
875 | ||
876 | if ( !m_internal->Create(this, stackSize) ) | |
877 | return wxTHREAD_NO_RESOURCE; | |
878 | ||
879 | return wxTHREAD_NO_ERROR; | |
880 | } | |
881 | ||
882 | wxThreadError wxThread::Run() | |
883 | { | |
884 | wxCriticalSectionLocker lock(m_critsect); | |
885 | ||
886 | if ( m_internal->GetState() != STATE_NEW ) | |
887 | { | |
888 | // actually, it may be almost any state at all, not only STATE_RUNNING | |
889 | return wxTHREAD_RUNNING; | |
890 | } | |
891 | ||
892 | // the thread has just been created and is still suspended - let it run | |
893 | return Resume(); | |
894 | } | |
895 | ||
896 | // suspend/resume thread | |
897 | // --------------------- | |
898 | ||
899 | wxThreadError wxThread::Pause() | |
900 | { | |
901 | wxCriticalSectionLocker lock(m_critsect); | |
902 | ||
903 | return m_internal->Suspend() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR; | |
904 | } | |
905 | ||
906 | wxThreadError wxThread::Resume() | |
907 | { | |
908 | wxCriticalSectionLocker lock(m_critsect); | |
909 | ||
910 | return m_internal->Resume() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR; | |
911 | } | |
912 | ||
913 | // stopping thread | |
914 | // --------------- | |
915 | ||
916 | wxThread::ExitCode wxThread::Wait() | |
917 | { | |
918 | // although under Windows we can wait for any thread, it's an error to | |
919 | // wait for a detached one in wxWin API | |
920 | wxCHECK_MSG( !IsDetached(), (ExitCode)-1, | |
921 | _T("can't wait for detached thread") ); | |
922 | ||
923 | ExitCode rc = (ExitCode)-1; | |
924 | ||
925 | (void)Delete(&rc); | |
926 | ||
927 | m_internal->Free(); | |
928 | ||
929 | return rc; | |
930 | } | |
931 | ||
932 | wxThreadError wxThread::Delete(ExitCode *pRc) | |
933 | { | |
934 | ExitCode rc = 0; | |
935 | ||
936 | // Delete() is always safe to call, so consider all possible states | |
937 | ||
938 | // we might need to resume the thread, but we might also not need to cancel | |
939 | // it if it doesn't run yet | |
940 | bool shouldResume = FALSE, | |
941 | shouldCancel = TRUE, | |
942 | isRunning = FALSE; | |
943 | ||
944 | // check if the thread already started to run | |
945 | { | |
946 | wxCriticalSectionLocker lock(m_critsect); | |
947 | ||
948 | if ( m_internal->GetState() == STATE_NEW ) | |
949 | { | |
950 | // WinThreadStart() will see it and terminate immediately, no need | |
951 | // to cancel the thread - but we still need to resume it to let it | |
952 | // run | |
953 | m_internal->SetState(STATE_EXITED); | |
954 | ||
955 | Resume(); // it knows about STATE_EXITED special case | |
956 | ||
957 | shouldCancel = FALSE; | |
958 | isRunning = TRUE; | |
959 | ||
960 | // shouldResume is correctly set to FALSE here | |
961 | } | |
962 | else | |
963 | { | |
964 | shouldResume = IsPaused(); | |
965 | } | |
966 | } | |
967 | ||
968 | // resume the thread if it is paused | |
969 | if ( shouldResume ) | |
970 | Resume(); | |
971 | ||
972 | HANDLE hThread = m_internal->GetHandle(); | |
973 | ||
974 | // does is still run? | |
975 | if ( isRunning || IsRunning() ) | |
976 | { | |
977 | if ( IsMain() ) | |
978 | { | |
979 | // set flag for wxIsWaitingForThread() | |
980 | gs_waitingForThread = TRUE; | |
981 | } | |
982 | ||
983 | // ask the thread to terminate | |
984 | if ( shouldCancel ) | |
985 | { | |
986 | wxCriticalSectionLocker lock(m_critsect); | |
987 | ||
988 | m_internal->Cancel(); | |
989 | } | |
990 | ||
991 | #if wxUSE_GUI | |
992 | // we can't just wait for the thread to terminate because it might be | |
993 | // calling some GUI functions and so it will never terminate before we | |
994 | // process the Windows messages that result from these functions | |
995 | DWORD result = 0; // suppress warnings from broken compilers | |
996 | do | |
997 | { | |
998 | if ( IsMain() ) | |
999 | { | |
1000 | // give the thread we're waiting for chance to do the GUI call | |
1001 | // it might be in | |
1002 | if ( (gs_nWaitingForGui > 0) && wxGuiOwnedByMainThread() ) | |
1003 | { | |
1004 | wxMutexGuiLeave(); | |
1005 | } | |
1006 | } | |
1007 | ||
1008 | result = ::MsgWaitForMultipleObjects | |
1009 | ( | |
1010 | 1, // number of objects to wait for | |
1011 | &hThread, // the objects | |
1012 | FALSE, // don't wait for all objects | |
1013 | INFINITE, // no timeout | |
1014 | QS_ALLINPUT | // return as soon as there are any events | |
1015 | QS_ALLPOSTMESSAGE | |
1016 | ); | |
1017 | ||
1018 | switch ( result ) | |
1019 | { | |
1020 | case 0xFFFFFFFF: | |
1021 | // error | |
1022 | wxLogSysError(_("Can not wait for thread termination")); | |
1023 | Kill(); | |
1024 | return wxTHREAD_KILLED; | |
1025 | ||
1026 | case WAIT_OBJECT_0: | |
1027 | // thread we're waiting for terminated | |
1028 | break; | |
1029 | ||
1030 | case WAIT_OBJECT_0 + 1: | |
1031 | // new message arrived, process it | |
1032 | if ( !wxTheApp->DoMessage() ) | |
1033 | { | |
1034 | // WM_QUIT received: kill the thread | |
1035 | Kill(); | |
1036 | ||
1037 | return wxTHREAD_KILLED; | |
1038 | } | |
1039 | break; | |
1040 | ||
1041 | default: | |
1042 | wxFAIL_MSG(wxT("unexpected result of MsgWaitForMultipleObject")); | |
1043 | } | |
1044 | } while ( result != WAIT_OBJECT_0 ); | |
1045 | #else // !wxUSE_GUI | |
1046 | // simply wait for the thread to terminate | |
1047 | // | |
1048 | // OTOH, even console apps create windows (in wxExecute, for WinSock | |
1049 | // &c), so may be use MsgWaitForMultipleObject() too here? | |
1050 | if ( WaitForSingleObject(hThread, INFINITE) != WAIT_OBJECT_0 ) | |
1051 | { | |
1052 | wxFAIL_MSG(wxT("unexpected result of WaitForSingleObject")); | |
1053 | } | |
1054 | #endif // wxUSE_GUI/!wxUSE_GUI | |
1055 | ||
1056 | if ( IsMain() ) | |
1057 | { | |
1058 | gs_waitingForThread = FALSE; | |
1059 | } | |
1060 | } | |
1061 | ||
1062 | // although the thread might be already in the EXITED state it might not | |
1063 | // have terminated yet and so we are not sure that it has actually | |
1064 | // terminated if the "if" above hadn't been taken | |
1065 | do | |
1066 | { | |
1067 | if ( !::GetExitCodeThread(hThread, (LPDWORD)&rc) ) | |
1068 | { | |
1069 | wxLogLastError(wxT("GetExitCodeThread")); | |
1070 | ||
1071 | rc = (ExitCode)-1; | |
1072 | } | |
1073 | } while ( (DWORD)rc == STILL_ACTIVE ); | |
1074 | ||
1075 | if ( IsDetached() ) | |
1076 | { | |
1077 | // if the thread exits normally, this is done in WinThreadStart, but in | |
1078 | // this case it would have been too early because | |
1079 | // MsgWaitForMultipleObject() would fail if the thread handle was | |
1080 | // closed while we were waiting on it, so we must do it here | |
1081 | delete this; | |
1082 | } | |
1083 | ||
1084 | if ( pRc ) | |
1085 | *pRc = rc; | |
1086 | ||
1087 | return rc == (ExitCode)-1 ? wxTHREAD_MISC_ERROR : wxTHREAD_NO_ERROR; | |
1088 | } | |
1089 | ||
1090 | wxThreadError wxThread::Kill() | |
1091 | { | |
1092 | if ( !IsRunning() ) | |
1093 | return wxTHREAD_NOT_RUNNING; | |
1094 | ||
1095 | if ( !::TerminateThread(m_internal->GetHandle(), (DWORD)-1) ) | |
1096 | { | |
1097 | wxLogSysError(_("Couldn't terminate thread")); | |
1098 | ||
1099 | return wxTHREAD_MISC_ERROR; | |
1100 | } | |
1101 | ||
1102 | m_internal->Free(); | |
1103 | ||
1104 | if ( IsDetached() ) | |
1105 | { | |
1106 | delete this; | |
1107 | } | |
1108 | ||
1109 | return wxTHREAD_NO_ERROR; | |
1110 | } | |
1111 | ||
1112 | void wxThread::Exit(ExitCode status) | |
1113 | { | |
1114 | m_internal->Free(); | |
1115 | ||
1116 | if ( IsDetached() ) | |
1117 | { | |
1118 | delete this; | |
1119 | } | |
1120 | ||
1121 | #ifdef wxUSE_BEGIN_THREAD | |
1122 | _endthreadex((unsigned)status); | |
1123 | #else // !VC++ | |
1124 | ::ExitThread((DWORD)status); | |
1125 | #endif // VC++/!VC++ | |
1126 | ||
1127 | wxFAIL_MSG(wxT("Couldn't return from ExitThread()!")); | |
1128 | } | |
1129 | ||
1130 | // priority setting | |
1131 | // ---------------- | |
1132 | ||
1133 | void wxThread::SetPriority(unsigned int prio) | |
1134 | { | |
1135 | wxCriticalSectionLocker lock(m_critsect); | |
1136 | ||
1137 | m_internal->SetPriority(prio); | |
1138 | } | |
1139 | ||
1140 | unsigned int wxThread::GetPriority() const | |
1141 | { | |
1142 | wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast | |
1143 | ||
1144 | return m_internal->GetPriority(); | |
1145 | } | |
1146 | ||
1147 | unsigned long wxThread::GetId() const | |
1148 | { | |
1149 | wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast | |
1150 | ||
1151 | return (unsigned long)m_internal->GetId(); | |
1152 | } | |
1153 | ||
1154 | bool wxThread::IsRunning() const | |
1155 | { | |
1156 | wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast | |
1157 | ||
1158 | return m_internal->GetState() == STATE_RUNNING; | |
1159 | } | |
1160 | ||
1161 | bool wxThread::IsAlive() const | |
1162 | { | |
1163 | wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast | |
1164 | ||
1165 | return (m_internal->GetState() == STATE_RUNNING) || | |
1166 | (m_internal->GetState() == STATE_PAUSED); | |
1167 | } | |
1168 | ||
1169 | bool wxThread::IsPaused() const | |
1170 | { | |
1171 | wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast | |
1172 | ||
1173 | return m_internal->GetState() == STATE_PAUSED; | |
1174 | } | |
1175 | ||
1176 | bool wxThread::TestDestroy() | |
1177 | { | |
1178 | wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect); // const_cast | |
1179 | ||
1180 | return m_internal->GetState() == STATE_CANCELED; | |
1181 | } | |
1182 | ||
1183 | // ---------------------------------------------------------------------------- | |
1184 | // Automatic initialization for thread module | |
1185 | // ---------------------------------------------------------------------------- | |
1186 | ||
1187 | class wxThreadModule : public wxModule | |
1188 | { | |
1189 | public: | |
1190 | virtual bool OnInit(); | |
1191 | virtual void OnExit(); | |
1192 | ||
1193 | private: | |
1194 | DECLARE_DYNAMIC_CLASS(wxThreadModule) | |
1195 | }; | |
1196 | ||
1197 | IMPLEMENT_DYNAMIC_CLASS(wxThreadModule, wxModule) | |
1198 | ||
1199 | bool wxThreadModule::OnInit() | |
1200 | { | |
1201 | // allocate TLS index for storing the pointer to the current thread | |
1202 | gs_tlsThisThread = ::TlsAlloc(); | |
1203 | if ( gs_tlsThisThread == 0xFFFFFFFF ) | |
1204 | { | |
1205 | // in normal circumstances it will only happen if all other | |
1206 | // TLS_MINIMUM_AVAILABLE (>= 64) indices are already taken - in other | |
1207 | // words, this should never happen | |
1208 | wxLogSysError(_("Thread module initialization failed: impossible to allocate index in thread local storage")); | |
1209 | ||
1210 | return FALSE; | |
1211 | } | |
1212 | ||
1213 | // main thread doesn't have associated wxThread object, so store 0 in the | |
1214 | // TLS instead | |
1215 | if ( !::TlsSetValue(gs_tlsThisThread, (LPVOID)0) ) | |
1216 | { | |
1217 | ::TlsFree(gs_tlsThisThread); | |
1218 | gs_tlsThisThread = 0xFFFFFFFF; | |
1219 | ||
1220 | wxLogSysError(_("Thread module initialization failed: can not store value in thread local storage")); | |
1221 | ||
1222 | return FALSE; | |
1223 | } | |
1224 | ||
1225 | gs_critsectWaitingForGui = new wxCriticalSection(); | |
1226 | ||
1227 | gs_critsectGui = new wxCriticalSection(); | |
1228 | gs_critsectGui->Enter(); | |
1229 | ||
1230 | // no error return for GetCurrentThreadId() | |
1231 | gs_idMainThread = ::GetCurrentThreadId(); | |
1232 | ||
1233 | return TRUE; | |
1234 | } | |
1235 | ||
1236 | void wxThreadModule::OnExit() | |
1237 | { | |
1238 | if ( !::TlsFree(gs_tlsThisThread) ) | |
1239 | { | |
1240 | wxLogLastError(wxT("TlsFree failed.")); | |
1241 | } | |
1242 | ||
1243 | if ( gs_critsectGui ) | |
1244 | { | |
1245 | gs_critsectGui->Leave(); | |
1246 | delete gs_critsectGui; | |
1247 | gs_critsectGui = NULL; | |
1248 | } | |
1249 | ||
1250 | delete gs_critsectWaitingForGui; | |
1251 | gs_critsectWaitingForGui = NULL; | |
1252 | } | |
1253 | ||
1254 | // ---------------------------------------------------------------------------- | |
1255 | // under Windows, these functions are implemented using a critical section and | |
1256 | // not a mutex, so the names are a bit confusing | |
1257 | // ---------------------------------------------------------------------------- | |
1258 | ||
1259 | void WXDLLEXPORT wxMutexGuiEnter() | |
1260 | { | |
1261 | // this would dead lock everything... | |
1262 | wxASSERT_MSG( !wxThread::IsMain(), | |
1263 | wxT("main thread doesn't want to block in wxMutexGuiEnter()!") ); | |
1264 | ||
1265 | // the order in which we enter the critical sections here is crucial!! | |
1266 | ||
1267 | // set the flag telling to the main thread that we want to do some GUI | |
1268 | { | |
1269 | wxCriticalSectionLocker enter(*gs_critsectWaitingForGui); | |
1270 | ||
1271 | gs_nWaitingForGui++; | |
1272 | } | |
1273 | ||
1274 | wxWakeUpMainThread(); | |
1275 | ||
1276 | // now we may block here because the main thread will soon let us in | |
1277 | // (during the next iteration of OnIdle()) | |
1278 | gs_critsectGui->Enter(); | |
1279 | } | |
1280 | ||
1281 | void WXDLLEXPORT wxMutexGuiLeave() | |
1282 | { | |
1283 | wxCriticalSectionLocker enter(*gs_critsectWaitingForGui); | |
1284 | ||
1285 | if ( wxThread::IsMain() ) | |
1286 | { | |
1287 | gs_bGuiOwnedByMainThread = FALSE; | |
1288 | } | |
1289 | else | |
1290 | { | |
1291 | // decrement the number of threads waiting for GUI access now | |
1292 | wxASSERT_MSG( gs_nWaitingForGui > 0, | |
1293 | wxT("calling wxMutexGuiLeave() without entering it first?") ); | |
1294 | ||
1295 | gs_nWaitingForGui--; | |
1296 | ||
1297 | wxWakeUpMainThread(); | |
1298 | } | |
1299 | ||
1300 | gs_critsectGui->Leave(); | |
1301 | } | |
1302 | ||
1303 | void WXDLLEXPORT wxMutexGuiLeaveOrEnter() | |
1304 | { | |
1305 | wxASSERT_MSG( wxThread::IsMain(), | |
1306 | wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") ); | |
1307 | ||
1308 | wxCriticalSectionLocker enter(*gs_critsectWaitingForGui); | |
1309 | ||
1310 | if ( gs_nWaitingForGui == 0 ) | |
1311 | { | |
1312 | // no threads are waiting for GUI - so we may acquire the lock without | |
1313 | // any danger (but only if we don't already have it) | |
1314 | if ( !wxGuiOwnedByMainThread() ) | |
1315 | { | |
1316 | gs_critsectGui->Enter(); | |
1317 | ||
1318 | gs_bGuiOwnedByMainThread = TRUE; | |
1319 | } | |
1320 | //else: already have it, nothing to do | |
1321 | } | |
1322 | else | |
1323 | { | |
1324 | // some threads are waiting, release the GUI lock if we have it | |
1325 | if ( wxGuiOwnedByMainThread() ) | |
1326 | { | |
1327 | wxMutexGuiLeave(); | |
1328 | } | |
1329 | //else: some other worker thread is doing GUI | |
1330 | } | |
1331 | } | |
1332 | ||
1333 | bool WXDLLEXPORT wxGuiOwnedByMainThread() | |
1334 | { | |
1335 | return gs_bGuiOwnedByMainThread; | |
1336 | } | |
1337 | ||
1338 | // wake up the main thread if it's in ::GetMessage() | |
1339 | void WXDLLEXPORT wxWakeUpMainThread() | |
1340 | { | |
1341 | // sending any message would do - hopefully WM_NULL is harmless enough | |
1342 | if ( !::PostThreadMessage(gs_idMainThread, WM_NULL, 0, 0) ) | |
1343 | { | |
1344 | // should never happen | |
1345 | wxLogLastError(wxT("PostThreadMessage(WM_NULL)")); | |
1346 | } | |
1347 | } | |
1348 | ||
1349 | bool WXDLLEXPORT wxIsWaitingForThread() | |
1350 | { | |
1351 | return gs_waitingForThread; | |
1352 | } | |
1353 | ||
1354 | // ---------------------------------------------------------------------------- | |
1355 | // include common implementation code | |
1356 | // ---------------------------------------------------------------------------- | |
1357 | ||
1358 | #include "wx/thrimpl.cpp" | |
1359 | ||
1360 | #endif // wxUSE_THREADS | |
1361 |