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( 10000 );
 308         wxASSERT_MSG( handled == 1, "No Event Available");
 309         m_shouldWaitForEvent = false;
 310     }
 311     return DispatchTimeout( 0 );
 312 }
 313
 314 bool wxCFEventLoop::Dispatch()
 315 {
 316     return DoProcessEvents() != 0;
 317 }
 318
 319 int wxCFEventLoop::DispatchTimeout(unsigned long timeout)
 320 {
 321     if ( !wxTheApp )
 322         return 0;
 323
 324     int status = DoDispatchTimeout(timeout);
 325
 326     switch( status )
 327     {
 328         case 0:
 329             break;
 330         case -1:
 331             if ( m_shouldExit )
 332                 return 0;
 333
 334             break;
 335         case 1:
 336             break;
 337     }
 338
 339     return status;
 340 }
 341
 342 int wxCFEventLoop::DoDispatchTimeout(unsigned long timeout)
 343 {
 344     SInt32 status = CFRunLoopRunInMode(kCFRunLoopDefaultMode, timeout / 1000.0 , true);
 345     switch( status )
 346     {
 347         case kCFRunLoopRunFinished:
 348             wxFAIL_MSG( "incorrect run loop state" );
 349             break;
 350         case kCFRunLoopRunStopped:
 351             return 0;
 352             break;
 353         case kCFRunLoopRunTimedOut:
 354             return -1;
 355             break;
 356         case kCFRunLoopRunHandledSource:
 357         default:
 358             break;
 359     }
 360     return 1;
 361 }
 362
 363 void wxCFEventLoop::DoRun()
 364 {
 365     for ( ;; )
 366     {
 367         // generate and process idle events for as long as we don't
 368         // have anything else to do
 369         DoProcessEvents();
 370
 371         // if the "should exit" flag is set, the loop should terminate
 372         // but not before processing any remaining messages so while
 373         // Pending() returns true, do process them
 374         if ( m_shouldExit )
 375         {
 376             while ( DoProcessEvents() == 1 )
 377                 ;
 378
 379             break;
 380         }
 381     }
 382 }
 383
 384 void wxCFEventLoop::DoStop()
 385 {
 386     CFRunLoopStop(CFGetCurrentRunLoop());
 387 }
 388
 389 // enters a loop calling OnNextIteration(), Pending() and Dispatch() and
 390 // terminating when Exit() is called
 391 int wxCFEventLoop::Run()
 392 {
 393     // event loops are not recursive, you need to create another loop!
 394     wxCHECK_MSG( !IsRunning(), -1, wxT("can't reenter a message loop") );
 395
 396     // ProcessIdle() and ProcessEvents() below may throw so the code here should
 397     // be exception-safe, hence we must use local objects for all actions we
 398     // should undo
 399     wxEventLoopActivator activate(this);
 400
 401     // we must ensure that OnExit() is called even if an exception is thrown
 402     // from inside ProcessEvents() but we must call it from Exit() in normal
 403     // situations because it is supposed to be called synchronously,
 404     // wxModalEventLoop depends on this (so we can't just use ON_BLOCK_EXIT or
 405     // something similar here)
 406 #if wxUSE_EXCEPTIONS
 407     for ( ;; )
 408     {
 409         try
 410         {
 411 #endif // wxUSE_EXCEPTIONS
 412
 413             DoRun();
 414
 415 #if wxUSE_EXCEPTIONS
 416             // exit the outer loop as well
 417             break;
 418         }
 419         catch ( ... )
 420         {
 421             try
 422             {
 423                 if ( !wxTheApp || !wxTheApp->OnExceptionInMainLoop() )
 424                 {
 425                     OnExit();
 426                     break;
 427                 }
 428                 //else: continue running the event loop
 429             }
 430             catch ( ... )
 431             {
 432                 // OnException() throwed, possibly rethrowing the same
 433                 // exception again: very good, but we still need OnExit() to
 434                 // be called
 435                 OnExit();
 436                 throw;
 437             }
 438         }
 439     }
 440 #endif // wxUSE_EXCEPTIONS
 441
 442     return m_exitcode;
 443 }
 444
 445 // sets the "should exit" flag and wakes up the loop so that it terminates
 446 // soon
 447 void wxCFEventLoop::Exit(int rc)
 448 {
 449     m_exitcode = rc;
 450     m_shouldExit = true;
 451     DoStop();
 452 }
 453
 454 wxCFEventLoopPauseIdleEvents::wxCFEventLoopPauseIdleEvents()
 455 {
 456     wxCFEventLoop* cfl = dynamic_cast<wxCFEventLoop*>(wxEventLoopBase::GetActive());
 457     if ( cfl )
 458     {
 459         m_formerState = cfl->ShouldProcessIdleEvents();
 460         cfl->SetProcessIdleEvents(false);
 461     }
 462     else
 463         m_formerState = true;
 464 }
 465
 466 wxCFEventLoopPauseIdleEvents::~wxCFEventLoopPauseIdleEvents()
 467 {
 468     wxCFEventLoop* cfl = dynamic_cast<wxCFEventLoop*>(wxEventLoopBase::GetActive());
 469     if ( cfl )
 470         cfl->SetProcessIdleEvents(m_formerState);
 471 }
 472
 473 // TODO Move to thread_osx.cpp
 474
 475 #if wxUSE_THREADS
 476
 477 // ----------------------------------------------------------------------------
 478 // GUI Serialization copied from MSW implementation
 479 // ----------------------------------------------------------------------------
 480
 481 // if it's false, some secondary thread is holding the GUI lock
 482 static bool gs_bGuiOwnedByMainThread = true;
 483
 484 // critical section which controls access to all GUI functions: any secondary
 485 // thread (i.e. except the main one) must enter this crit section before doing
 486 // any GUI calls
 487 static wxCriticalSection *gs_critsectGui = NULL;
 488
 489 // critical section which protects gs_nWaitingForGui variable
 490 static wxCriticalSection *gs_critsectWaitingForGui = NULL;
 491
 492 // number of threads waiting for GUI in wxMutexGuiEnter()
 493 static size_t gs_nWaitingForGui = 0;
 494
 495 void wxOSXThreadModuleOnInit()
 496 {
 497     gs_critsectWaitingForGui = new wxCriticalSection();
 498     gs_critsectGui = new wxCriticalSection();
 499     gs_critsectGui->Enter();
 500 }
 501
 502
 503 void wxOSXThreadModuleOnExit()
 504 {
 505     if ( gs_critsectGui )
 506     {
 507         if ( !wxGuiOwnedByMainThread() )
 508         {
 509             gs_critsectGui->Enter();
 510             gs_bGuiOwnedByMainThread = true;
 511         }
 512
 513         gs_critsectGui->Leave();
 514         wxDELETE(gs_critsectGui);
 515     }
 516
 517     wxDELETE(gs_critsectWaitingForGui);
 518 }
 519
 520
 521 // wake up the main thread
 522 void WXDLLIMPEXP_BASE wxWakeUpMainThread()
 523 {
 524     wxMacWakeUp();
 525 }
 526
 527 void wxMutexGuiEnterImpl()
 528 {
 529     // this would dead lock everything...
 530     wxASSERT_MSG( !wxThread::IsMain(),
 531                  wxT("main thread doesn't want to block in wxMutexGuiEnter()!") );
 532
 533     // the order in which we enter the critical sections here is crucial!!
 534
 535     // set the flag telling to the main thread that we want to do some GUI
 536     {
 537         wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 538
 539         gs_nWaitingForGui++;
 540     }
 541
 542     wxWakeUpMainThread();
 543
 544     // now we may block here because the main thread will soon let us in
 545     // (during the next iteration of OnIdle())
 546     gs_critsectGui->Enter();
 547 }
 548
 549 void wxMutexGuiLeaveImpl()
 550 {
 551     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 552
 553     if ( wxThread::IsMain() )
 554     {
 555         gs_bGuiOwnedByMainThread = false;
 556     }
 557     else
 558     {
 559         // decrement the number of threads waiting for GUI access now
 560         wxASSERT_MSG( gs_nWaitingForGui > 0,
 561                      wxT("calling wxMutexGuiLeave() without entering it first?") );
 562
 563         gs_nWaitingForGui--;
 564
 565         wxWakeUpMainThread();
 566     }
 567
 568     gs_critsectGui->Leave();
 569 }
 570
 571 void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter()
 572 {
 573     wxASSERT_MSG( wxThread::IsMain(),
 574                  wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") );
 575
 576     if ( !gs_critsectWaitingForGui )
 577         return;
 578
 579     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 580
 581     if ( gs_nWaitingForGui == 0 )
 582     {
 583         // no threads are waiting for GUI - so we may acquire the lock without
 584         // any danger (but only if we don't already have it)
 585         if ( !wxGuiOwnedByMainThread() )
 586         {
 587             gs_critsectGui->Enter();
 588
 589             gs_bGuiOwnedByMainThread = true;
 590         }
 591         //else: already have it, nothing to do
 592     }
 593     else
 594     {
 595         // some threads are waiting, release the GUI lock if we have it
 596         if ( wxGuiOwnedByMainThread() )
 597             wxMutexGuiLeave();
 598         //else: some other worker thread is doing GUI
 599     }
 600 }
 601
 602 bool WXDLLIMPEXP_BASE wxGuiOwnedByMainThread()
 603 {
 604     return gs_bGuiOwnedByMainThread;
 605 }
 606
 607 #endif