src/osx/core/evtloop_cf.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/osx/core/evtloop_cf.cpp
   3 // Purpose:     wxEventLoop implementation common to both Carbon and Cocoa
   4 // Author:      Vadim Zeitlin
   5 // Created:     2009-10-18
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2009 Vadim Zeitlin <vadim@wxwidgets.org>
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 // ============================================================================
  12 // declarations
  13 // ============================================================================
  14
  15 // ----------------------------------------------------------------------------
  16 // headers
  17 // ----------------------------------------------------------------------------
  18
  19 // for compilers that support precompilation, includes "wx.h".
  20 #include "wx/wxprec.h"
  21
  22 #ifdef __BORLANDC__
  23     #pragma hdrstop
  24 #endif
  25
  26 #include "wx/evtloop.h"
  27
  28 #ifndef WX_PRECOMP
  29     #include "wx/log.h"
  30     #include "wx/app.h"
  31 #endif
  32
  33 #include "wx/evtloopsrc.h"
  34
  35 #include "wx/scopedptr.h"
  36
  37 #include "wx/osx/private.h"
  38 #include "wx/osx/core/cfref.h"
  39 #include "wx/thread.h"
  40
  41 #if wxUSE_GUI
  42     #include "wx/nonownedwnd.h"
  43 #endif
  44
  45 // ============================================================================
  46 // wxCFEventLoopSource and wxCFEventLoop implementation
  47 // ============================================================================
  48
  49 #if wxUSE_EVENTLOOP_SOURCE
  50
  51 namespace
  52 {
  53
  54 void EnableDescriptorCallBacks(CFFileDescriptorRef cffd, int flags)
  55 {
  56     if ( flags & wxEVENT_SOURCE_INPUT )
  57         CFFileDescriptorEnableCallBacks(cffd, kCFFileDescriptorReadCallBack);
  58     if ( flags & wxEVENT_SOURCE_OUTPUT )
  59         CFFileDescriptorEnableCallBacks(cffd, kCFFileDescriptorWriteCallBack);
  60 }
  61
  62 void
  63 wx_cffiledescriptor_callback(CFFileDescriptorRef cffd,
  64                              CFOptionFlags flags,
  65                              void *ctxData)
  66 {
  67     wxLogTrace(wxTRACE_EVT_SOURCE,
  68                "CFFileDescriptor callback, flags=%d", flags);
  69
  70     wxCFEventLoopSource * const
  71         source = static_cast<wxCFEventLoopSource *>(ctxData);
  72
  73     wxEventLoopSourceHandler * const
  74         handler = source->GetHandler();
  75     if ( flags & kCFFileDescriptorReadCallBack )
  76         handler->OnReadWaiting();
  77     if ( flags & kCFFileDescriptorWriteCallBack )
  78         handler->OnWriteWaiting();
  79
  80     // we need to re-enable callbacks to be called again
  81     EnableDescriptorCallBacks(cffd, source->GetFlags());
  82 }
  83
  84 } // anonymous namespace
  85
  86 wxEventLoopSource *
  87 wxCFEventLoop::AddSourceForFD(int fd,
  88                               wxEventLoopSourceHandler *handler,
  89                               int flags)
  90 {
  91     wxCHECK_MSG( fd != -1, NULL, "can't monitor invalid fd" );
  92
  93     wxScopedPtr<wxCFEventLoopSource>
  94         source(new wxCFEventLoopSource(handler, flags));
  95
  96     CFFileDescriptorContext ctx = { 0, source.get(), NULL, NULL, NULL };
  97     wxCFRef<CFFileDescriptorRef>
  98         cffd(CFFileDescriptorCreate
  99              (
 100                   kCFAllocatorDefault,
 101                   fd,
 102                   true,   // close on invalidate
 103                   wx_cffiledescriptor_callback,
 104                   &ctx
 105              ));
 106     if ( !cffd )
 107         return NULL;
 108
 109     wxCFRef<CFRunLoopSourceRef>
 110         cfsrc(CFFileDescriptorCreateRunLoopSource(kCFAllocatorDefault, cffd, 0));
 111     if ( !cfsrc )
 112         return NULL;
 113
 114     CFRunLoopRef cfloop = CFGetCurrentRunLoop();
 115     CFRunLoopAddSource(cfloop, cfsrc, kCFRunLoopDefaultMode);
 116
 117     // Enable the callbacks initially.
 118     EnableDescriptorCallBacks(cffd, source->GetFlags());
 119
 120     source->SetFileDescriptor(cffd.release());
 121
 122     return source.release();
 123 }
 124
 125 void wxCFEventLoopSource::SetFileDescriptor(CFFileDescriptorRef cffd)
 126 {
 127     wxASSERT_MSG( !m_cffd, "shouldn't be called more than once" );
 128
 129     m_cffd = cffd;
 130 }
 131
 132 wxCFEventLoopSource::~wxCFEventLoopSource()
 133 {
 134     if ( m_cffd )
 135         CFRelease(m_cffd);
 136 }
 137
 138 #endif // wxUSE_EVENTLOOP_SOURCE
 139
 140 void wxCFEventLoop::OSXCommonModeObserverCallBack(CFRunLoopObserverRef observer, int activity, void *info)
 141 {
 142     wxCFEventLoop * eventloop = static_cast<wxCFEventLoop *>(info);
 143     if ( eventloop )
 144         eventloop->CommonModeObserverCallBack(observer, activity);
 145 }
 146
 147 void wxCFEventLoop::OSXDefaultModeObserverCallBack(CFRunLoopObserverRef observer, int activity, void *info)
 148 {
 149     wxCFEventLoop * eventloop = static_cast<wxCFEventLoop *>(info);
 150     if ( eventloop )
 151         eventloop->DefaultModeObserverCallBack(observer, activity);
 152 }
 153
 154 void wxCFEventLoop::CommonModeObserverCallBack(CFRunLoopObserverRef WXUNUSED(observer), int activity)
 155 {
 156     if ( activity & kCFRunLoopBeforeTimers )
 157     {
 158         // process pending wx events first as they correspond to low-level events
 159         // which happened before, i.e. typically pending events were queued by a
 160         // previous call to Dispatch() and if we didn't process them now the next
 161         // call to it might enqueue them again (as happens with e.g. socket events
 162         // which would be generated as long as there is input available on socket
 163         // and this input is only removed from it when pending event handlers are
 164         // executed)
 165
 166         if ( wxTheApp && ShouldProcessIdleEvents() )
 167             wxTheApp->ProcessPendingEvents();
 168     }
 169
 170     if ( activity & kCFRunLoopBeforeWaiting )
 171     {
 172         if ( ShouldProcessIdleEvents() && ProcessIdle() )
 173         {
 174             WakeUp();
 175         }
 176         else
 177         {
 178 #if wxUSE_THREADS
 179             wxMutexGuiLeaveOrEnter();
 180 #endif
 181         }
 182     }
 183 }
 184
 185 void
 186 wxCFEventLoop::DefaultModeObserverCallBack(CFRunLoopObserverRef WXUNUSED(observer),
 187                                            int WXUNUSED(activity))
 188 {
 189     /*
 190     if ( activity & kCFRunLoopBeforeTimers )
 191     {
 192     }
 193
 194     if ( activity & kCFRunLoopBeforeWaiting )
 195     {
 196     }
 197     */
 198 }
 199
 200
 201 wxCFEventLoop::wxCFEventLoop()
 202 {
 203     m_shouldExit = false;
 204     m_processIdleEvents = true;
 205
 206 #if wxUSE_UIACTIONSIMULATOR
 207     m_shouldWaitForEvent = false;
 208 #endif
 209
 210     m_runLoop = CFGetCurrentRunLoop();
 211
 212     CFRunLoopObserverContext ctxt;
 213     bzero( &ctxt, sizeof(ctxt) );
 214     ctxt.info = this;
 215     m_commonModeRunLoopObserver = CFRunLoopObserverCreate( kCFAllocatorDefault, kCFRunLoopBeforeTimers | kCFRunLoopBeforeWaiting , true /* repeats */, 0,
 216                                                           (CFRunLoopObserverCallBack) wxCFEventLoop::OSXCommonModeObserverCallBack, &ctxt );
 217     CFRunLoopAddObserver(m_runLoop, m_commonModeRunLoopObserver, kCFRunLoopCommonModes);
 218
 219     m_defaultModeRunLoopObserver = CFRunLoopObserverCreate( kCFAllocatorDefault, kCFRunLoopBeforeTimers | kCFRunLoopBeforeWaiting , true /* repeats */, 0,
 220                                                            (CFRunLoopObserverCallBack) wxCFEventLoop::OSXDefaultModeObserverCallBack, &ctxt );
 221     CFRunLoopAddObserver(m_runLoop, m_defaultModeRunLoopObserver, kCFRunLoopDefaultMode);
 222 }
 223
 224 wxCFEventLoop::~wxCFEventLoop()
 225 {
 226     CFRunLoopRemoveObserver(m_runLoop, m_commonModeRunLoopObserver, kCFRunLoopCommonModes);
 227     CFRunLoopRemoveObserver(m_runLoop, m_defaultModeRunLoopObserver, kCFRunLoopDefaultMode);
 228
 229     CFRelease(m_defaultModeRunLoopObserver);
 230     CFRelease(m_commonModeRunLoopObserver);
 231 }
 232
 233
 234 CFRunLoopRef wxCFEventLoop::CFGetCurrentRunLoop() const
 235 {
 236     return CFRunLoopGetCurrent();
 237 }
 238
 239 void wxCFEventLoop::WakeUp()
 240 {
 241     CFRunLoopWakeUp(m_runLoop);
 242 }
 243
 244 #if wxUSE_BASE
 245
 246 void wxMacWakeUp()
 247 {
 248     wxEventLoopBase * const loop = wxEventLoopBase::GetActive();
 249
 250     if ( loop )
 251         loop->WakeUp();
 252 }
 253
 254 #endif
 255
 256 bool wxCFEventLoop::YieldFor(long eventsToProcess)
 257 {
 258 #if wxUSE_THREADS
 259     // Yielding from a non-gui thread needs to bail out, otherwise we end up
 260     // possibly sending events in the thread too.
 261     if ( !wxThread::IsMain() )
 262     {
 263         return true;
 264     }
 265 #endif // wxUSE_THREADS
 266
 267     m_isInsideYield = true;
 268     m_eventsToProcessInsideYield = eventsToProcess;
 269
 270 #if wxUSE_LOG
 271     // disable log flushing from here because a call to wxYield() shouldn't
 272     // normally result in message boxes popping up &c
 273     wxLog::Suspend();
 274 #endif // wxUSE_LOG
 275
 276     // process all pending events:
 277     while ( DoProcessEvents() == 1 )
 278         ;
 279
 280     // it's necessary to call ProcessIdle() to update the frames sizes which
 281     // might have been changed (it also will update other things set from
 282     // OnUpdateUI() which is a nice (and desired) side effect)
 283     while ( ProcessIdle() ) {}
 284
 285     // if there are pending events, we must process them.
 286     if (wxTheApp)
 287         wxTheApp->ProcessPendingEvents();
 288
 289 #if wxUSE_LOG
 290     wxLog::Resume();
 291 #endif // wxUSE_LOG
 292     m_isInsideYield = false;
 293
 294     return true;
 295 }
 296
 297 // implement/override base class pure virtual
 298 bool wxCFEventLoop::Pending() const
 299 {
 300     return true;
 301 }
 302
 303 int wxCFEventLoop::DoProcessEvents()
 304 {
 305     if ( m_shouldWaitForEvent )
 306     {
 307         int  handled = DispatchTimeout( 1000 );
 308         wxASSERT_MSG( handled == 1, "No Event Available");
 309         m_shouldWaitForEvent = false;
 310         return handled;
 311     }
 312     else
 313         return DispatchTimeout( 0 );
 314 }
 315
 316 bool wxCFEventLoop::Dispatch()
 317 {
 318     return DoProcessEvents() != 0;
 319 }
 320
 321 int wxCFEventLoop::DispatchTimeout(unsigned long timeout)
 322 {
 323     if ( !wxTheApp )
 324         return 0;
 325
 326     int status = DoDispatchTimeout(timeout);
 327
 328     switch( status )
 329     {
 330         case 0:
 331             break;
 332         case -1:
 333             if ( m_shouldExit )
 334                 return 0;
 335
 336             break;
 337         case 1:
 338             break;
 339     }
 340
 341     return status;
 342 }
 343
 344 int wxCFEventLoop::DoDispatchTimeout(unsigned long timeout)
 345 {
 346     SInt32 status = CFRunLoopRunInMode(kCFRunLoopDefaultMode, timeout / 1000.0 , true);
 347     switch( status )
 348     {
 349         case kCFRunLoopRunFinished:
 350             wxFAIL_MSG( "incorrect run loop state" );
 351             break;
 352         case kCFRunLoopRunStopped:
 353             return 0;
 354             break;
 355         case kCFRunLoopRunTimedOut:
 356             return -1;
 357             break;
 358         case kCFRunLoopRunHandledSource:
 359         default:
 360             break;
 361     }
 362     return 1;
 363 }
 364
 365 void wxCFEventLoop::DoRun()
 366 {
 367     for ( ;; )
 368     {
 369         // generate and process idle events for as long as we don't
 370         // have anything else to do
 371         DoProcessEvents();
 372
 373         // if the "should exit" flag is set, the loop should terminate
 374         // but not before processing any remaining messages so while
 375         // Pending() returns true, do process them
 376         if ( m_shouldExit )
 377         {
 378             while ( DoProcessEvents() == 1 )
 379                 ;
 380
 381             break;
 382         }
 383     }
 384 }
 385
 386 void wxCFEventLoop::DoStop()
 387 {
 388     CFRunLoopStop(CFGetCurrentRunLoop());
 389 }
 390
 391 // enters a loop calling OnNextIteration(), Pending() and Dispatch() and
 392 // terminating when Exit() is called
 393 int wxCFEventLoop::Run()
 394 {
 395     // event loops are not recursive, you need to create another loop!
 396     wxCHECK_MSG( !IsRunning(), -1, wxT("can't reenter a message loop") );
 397
 398     // ProcessIdle() and ProcessEvents() below may throw so the code here should
 399     // be exception-safe, hence we must use local objects for all actions we
 400     // should undo
 401     wxEventLoopActivator activate(this);
 402
 403     // we must ensure that OnExit() is called even if an exception is thrown
 404     // from inside ProcessEvents() but we must call it from Exit() in normal
 405     // situations because it is supposed to be called synchronously,
 406     // wxModalEventLoop depends on this (so we can't just use ON_BLOCK_EXIT or
 407     // something similar here)
 408 #if wxUSE_EXCEPTIONS
 409     for ( ;; )
 410     {
 411         try
 412         {
 413 #endif // wxUSE_EXCEPTIONS
 414
 415             DoRun();
 416
 417 #if wxUSE_EXCEPTIONS
 418             // exit the outer loop as well
 419             break;
 420         }
 421         catch ( ... )
 422         {
 423             try
 424             {
 425                 if ( !wxTheApp || !wxTheApp->OnExceptionInMainLoop() )
 426                 {
 427                     OnExit();
 428                     break;
 429                 }
 430                 //else: continue running the event loop
 431             }
 432             catch ( ... )
 433             {
 434                 // OnException() throwed, possibly rethrowing the same
 435                 // exception again: very good, but we still need OnExit() to
 436                 // be called
 437                 OnExit();
 438                 throw;
 439             }
 440         }
 441     }
 442 #endif // wxUSE_EXCEPTIONS
 443
 444     return m_exitcode;
 445 }
 446
 447 // sets the "should exit" flag and wakes up the loop so that it terminates
 448 // soon
 449 void wxCFEventLoop::Exit(int rc)
 450 {
 451     m_exitcode = rc;
 452     m_shouldExit = true;
 453     DoStop();
 454 }
 455
 456 wxCFEventLoopPauseIdleEvents::wxCFEventLoopPauseIdleEvents()
 457 {
 458     wxCFEventLoop* cfl = dynamic_cast<wxCFEventLoop*>(wxEventLoopBase::GetActive());
 459     if ( cfl )
 460     {
 461         m_formerState = cfl->ShouldProcessIdleEvents();
 462         cfl->SetProcessIdleEvents(false);
 463     }
 464     else
 465         m_formerState = true;
 466 }
 467
 468 wxCFEventLoopPauseIdleEvents::~wxCFEventLoopPauseIdleEvents()
 469 {
 470     wxCFEventLoop* cfl = dynamic_cast<wxCFEventLoop*>(wxEventLoopBase::GetActive());
 471     if ( cfl )
 472         cfl->SetProcessIdleEvents(m_formerState);
 473 }
 474
 475 // TODO Move to thread_osx.cpp
 476
 477 #if wxUSE_THREADS
 478
 479 // ----------------------------------------------------------------------------
 480 // GUI Serialization copied from MSW implementation
 481 // ----------------------------------------------------------------------------
 482
 483 // if it's false, some secondary thread is holding the GUI lock
 484 static bool gs_bGuiOwnedByMainThread = true;
 485
 486 // critical section which controls access to all GUI functions: any secondary
 487 // thread (i.e. except the main one) must enter this crit section before doing
 488 // any GUI calls
 489 static wxCriticalSection *gs_critsectGui = NULL;
 490
 491 // critical section which protects gs_nWaitingForGui variable
 492 static wxCriticalSection *gs_critsectWaitingForGui = NULL;
 493
 494 // number of threads waiting for GUI in wxMutexGuiEnter()
 495 static size_t gs_nWaitingForGui = 0;
 496
 497 void wxOSXThreadModuleOnInit()
 498 {
 499     gs_critsectWaitingForGui = new wxCriticalSection();
 500     gs_critsectGui = new wxCriticalSection();
 501     gs_critsectGui->Enter();
 502 }
 503
 504
 505 void wxOSXThreadModuleOnExit()
 506 {
 507     if ( gs_critsectGui )
 508     {
 509         if ( !wxGuiOwnedByMainThread() )
 510         {
 511             gs_critsectGui->Enter();
 512             gs_bGuiOwnedByMainThread = true;
 513         }
 514
 515         gs_critsectGui->Leave();
 516         wxDELETE(gs_critsectGui);
 517     }
 518
 519     wxDELETE(gs_critsectWaitingForGui);
 520 }
 521
 522
 523 // wake up the main thread
 524 void WXDLLIMPEXP_BASE wxWakeUpMainThread()
 525 {
 526     wxMacWakeUp();
 527 }
 528
 529 void wxMutexGuiEnterImpl()
 530 {
 531     // this would dead lock everything...
 532     wxASSERT_MSG( !wxThread::IsMain(),
 533                  wxT("main thread doesn't want to block in wxMutexGuiEnter()!") );
 534
 535     // the order in which we enter the critical sections here is crucial!!
 536
 537     // set the flag telling to the main thread that we want to do some GUI
 538     {
 539         wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 540
 541         gs_nWaitingForGui++;
 542     }
 543
 544     wxWakeUpMainThread();
 545
 546     // now we may block here because the main thread will soon let us in
 547     // (during the next iteration of OnIdle())
 548     gs_critsectGui->Enter();
 549 }
 550
 551 void wxMutexGuiLeaveImpl()
 552 {
 553     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 554
 555     if ( wxThread::IsMain() )
 556     {
 557         gs_bGuiOwnedByMainThread = false;
 558     }
 559     else
 560     {
 561         // decrement the number of threads waiting for GUI access now
 562         wxASSERT_MSG( gs_nWaitingForGui > 0,
 563                      wxT("calling wxMutexGuiLeave() without entering it first?") );
 564
 565         gs_nWaitingForGui--;
 566
 567         wxWakeUpMainThread();
 568     }
 569
 570     gs_critsectGui->Leave();
 571 }
 572
 573 void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter()
 574 {
 575     wxASSERT_MSG( wxThread::IsMain(),
 576                  wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") );
 577
 578     if ( !gs_critsectWaitingForGui )
 579         return;
 580
 581     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 582
 583     if ( gs_nWaitingForGui == 0 )
 584     {
 585         // no threads are waiting for GUI - so we may acquire the lock without
 586         // any danger (but only if we don't already have it)
 587         if ( !wxGuiOwnedByMainThread() )
 588         {
 589             gs_critsectGui->Enter();
 590
 591             gs_bGuiOwnedByMainThread = true;
 592         }
 593         //else: already have it, nothing to do
 594     }
 595     else
 596     {
 597         // some threads are waiting, release the GUI lock if we have it
 598         if ( wxGuiOwnedByMainThread() )
 599             wxMutexGuiLeave();
 600         //else: some other worker thread is doing GUI
 601     }
 602 }
 603
 604 bool WXDLLIMPEXP_BASE wxGuiOwnedByMainThread()
 605 {
 606     return gs_bGuiOwnedByMainThread;
 607 }
 608
 609 #endif