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     m_runLoop = CFGetCurrentRunLoop();
 207
 208     CFRunLoopObserverContext ctxt;
 209     bzero( &ctxt, sizeof(ctxt) );
 210     ctxt.info = this;
 211     m_commonModeRunLoopObserver = CFRunLoopObserverCreate( kCFAllocatorDefault, kCFRunLoopBeforeTimers | kCFRunLoopBeforeWaiting , true /* repeats */, 0,
 212                                                           (CFRunLoopObserverCallBack) wxCFEventLoop::OSXCommonModeObserverCallBack, &ctxt );
 213     CFRunLoopAddObserver(m_runLoop, m_commonModeRunLoopObserver, kCFRunLoopCommonModes);
 214
 215     m_defaultModeRunLoopObserver = CFRunLoopObserverCreate( kCFAllocatorDefault, kCFRunLoopBeforeTimers | kCFRunLoopBeforeWaiting , true /* repeats */, 0,
 216                                                            (CFRunLoopObserverCallBack) wxCFEventLoop::OSXDefaultModeObserverCallBack, &ctxt );
 217     CFRunLoopAddObserver(m_runLoop, m_defaultModeRunLoopObserver, kCFRunLoopDefaultMode);
 218 }
 219
 220 wxCFEventLoop::~wxCFEventLoop()
 221 {
 222     CFRunLoopRemoveObserver(m_runLoop, m_commonModeRunLoopObserver, kCFRunLoopCommonModes);
 223     CFRunLoopRemoveObserver(m_runLoop, m_defaultModeRunLoopObserver, kCFRunLoopDefaultMode);
 224
 225     CFRelease(m_defaultModeRunLoopObserver);
 226     CFRelease(m_commonModeRunLoopObserver);
 227 }
 228
 229
 230 CFRunLoopRef wxCFEventLoop::CFGetCurrentRunLoop() const
 231 {
 232     return CFRunLoopGetCurrent();
 233 }
 234
 235 void wxCFEventLoop::WakeUp()
 236 {
 237     CFRunLoopWakeUp(m_runLoop);
 238 }
 239
 240 #if wxUSE_BASE
 241
 242 void wxMacWakeUp()
 243 {
 244     wxEventLoopBase * const loop = wxEventLoopBase::GetActive();
 245
 246     if ( loop )
 247         loop->WakeUp();
 248 }
 249
 250 #endif
 251
 252 bool wxCFEventLoop::YieldFor(long eventsToProcess)
 253 {
 254 #if wxUSE_THREADS
 255     // Yielding from a non-gui thread needs to bail out, otherwise we end up
 256     // possibly sending events in the thread too.
 257     if ( !wxThread::IsMain() )
 258     {
 259         return true;
 260     }
 261 #endif // wxUSE_THREADS
 262
 263     m_isInsideYield = true;
 264     m_eventsToProcessInsideYield = eventsToProcess;
 265
 266 #if wxUSE_LOG
 267     // disable log flushing from here because a call to wxYield() shouldn't
 268     // normally result in message boxes popping up &c
 269     wxLog::Suspend();
 270 #endif // wxUSE_LOG
 271
 272     // process all pending events:
 273     while ( DoProcessEvents() == 1 )
 274         ;
 275
 276     // it's necessary to call ProcessIdle() to update the frames sizes which
 277     // might have been changed (it also will update other things set from
 278     // OnUpdateUI() which is a nice (and desired) side effect)
 279     while ( ProcessIdle() ) {}
 280
 281     // if there are pending events, we must process them.
 282     if (wxTheApp)
 283         wxTheApp->ProcessPendingEvents();
 284
 285 #if wxUSE_LOG
 286     wxLog::Resume();
 287 #endif // wxUSE_LOG
 288     m_isInsideYield = false;
 289
 290     return true;
 291 }
 292
 293 // implement/override base class pure virtual
 294 bool wxCFEventLoop::Pending() const
 295 {
 296     return true;
 297 }
 298
 299 int wxCFEventLoop::DoProcessEvents()
 300 {
 301     return DispatchTimeout( 0 );
 302 }
 303
 304 bool wxCFEventLoop::Dispatch()
 305 {
 306     return DoProcessEvents() != 0;
 307 }
 308
 309 int wxCFEventLoop::DispatchTimeout(unsigned long timeout)
 310 {
 311     if ( !wxTheApp )
 312         return 0;
 313
 314     int status = DoDispatchTimeout(timeout);
 315
 316     switch( status )
 317     {
 318         case 0:
 319             break;
 320         case -1:
 321             if ( m_shouldExit )
 322                 return 0;
 323
 324             break;
 325         case 1:
 326             break;
 327     }
 328
 329     return status;
 330 }
 331
 332 int wxCFEventLoop::DoDispatchTimeout(unsigned long timeout)
 333 {
 334     SInt32 status = CFRunLoopRunInMode(kCFRunLoopDefaultMode, timeout / 1000.0 , true);
 335     switch( status )
 336     {
 337         case kCFRunLoopRunFinished:
 338             wxFAIL_MSG( "incorrect run loop state" );
 339             break;
 340         case kCFRunLoopRunStopped:
 341             return 0;
 342             break;
 343         case kCFRunLoopRunTimedOut:
 344             return -1;
 345             break;
 346         case kCFRunLoopRunHandledSource:
 347         default:
 348             break;
 349     }
 350     return 1;
 351 }
 352
 353 void wxCFEventLoop::DoRun()
 354 {
 355     for ( ;; )
 356     {
 357         // generate and process idle events for as long as we don't
 358         // have anything else to do
 359         DoProcessEvents();
 360
 361         // if the "should exit" flag is set, the loop should terminate
 362         // but not before processing any remaining messages so while
 363         // Pending() returns true, do process them
 364         if ( m_shouldExit )
 365         {
 366             while ( DoProcessEvents() == 1 )
 367                 ;
 368
 369             break;
 370         }
 371     }
 372 }
 373
 374 void wxCFEventLoop::DoStop()
 375 {
 376     CFRunLoopStop(CFGetCurrentRunLoop());
 377 }
 378
 379 // enters a loop calling OnNextIteration(), Pending() and Dispatch() and
 380 // terminating when Exit() is called
 381 int wxCFEventLoop::Run()
 382 {
 383     // event loops are not recursive, you need to create another loop!
 384     wxCHECK_MSG( !IsRunning(), -1, wxT("can't reenter a message loop") );
 385
 386     // ProcessIdle() and ProcessEvents() below may throw so the code here should
 387     // be exception-safe, hence we must use local objects for all actions we
 388     // should undo
 389     wxEventLoopActivator activate(this);
 390
 391     // we must ensure that OnExit() is called even if an exception is thrown
 392     // from inside ProcessEvents() but we must call it from Exit() in normal
 393     // situations because it is supposed to be called synchronously,
 394     // wxModalEventLoop depends on this (so we can't just use ON_BLOCK_EXIT or
 395     // something similar here)
 396 #if wxUSE_EXCEPTIONS
 397     for ( ;; )
 398     {
 399         try
 400         {
 401 #endif // wxUSE_EXCEPTIONS
 402
 403             DoRun();
 404
 405 #if wxUSE_EXCEPTIONS
 406             // exit the outer loop as well
 407             break;
 408         }
 409         catch ( ... )
 410         {
 411             try
 412             {
 413                 if ( !wxTheApp || !wxTheApp->OnExceptionInMainLoop() )
 414                 {
 415                     OnExit();
 416                     break;
 417                 }
 418                 //else: continue running the event loop
 419             }
 420             catch ( ... )
 421             {
 422                 // OnException() throwed, possibly rethrowing the same
 423                 // exception again: very good, but we still need OnExit() to
 424                 // be called
 425                 OnExit();
 426                 throw;
 427             }
 428         }
 429     }
 430 #endif // wxUSE_EXCEPTIONS
 431
 432     return m_exitcode;
 433 }
 434
 435 // sets the "should exit" flag and wakes up the loop so that it terminates
 436 // soon
 437 void wxCFEventLoop::Exit(int rc)
 438 {
 439     m_exitcode = rc;
 440     m_shouldExit = true;
 441     DoStop();
 442 }
 443
 444 wxCFEventLoopPauseIdleEvents::wxCFEventLoopPauseIdleEvents()
 445 {
 446     wxCFEventLoop* cfl = dynamic_cast<wxCFEventLoop*>(wxEventLoopBase::GetActive());
 447     if ( cfl )
 448     {
 449         m_formerState = cfl->ShouldProcessIdleEvents();
 450         cfl->SetProcessIdleEvents(false);
 451     }
 452     else
 453         m_formerState = true;
 454 }
 455
 456 wxCFEventLoopPauseIdleEvents::~wxCFEventLoopPauseIdleEvents()
 457 {
 458     wxCFEventLoop* cfl = dynamic_cast<wxCFEventLoop*>(wxEventLoopBase::GetActive());
 459     if ( cfl )
 460         cfl->SetProcessIdleEvents(m_formerState);
 461 }
 462
 463 // TODO Move to thread_osx.cpp
 464
 465 #if wxUSE_THREADS
 466
 467 // ----------------------------------------------------------------------------
 468 // GUI Serialization copied from MSW implementation
 469 // ----------------------------------------------------------------------------
 470
 471 // if it's false, some secondary thread is holding the GUI lock
 472 static bool gs_bGuiOwnedByMainThread = true;
 473
 474 // critical section which controls access to all GUI functions: any secondary
 475 // thread (i.e. except the main one) must enter this crit section before doing
 476 // any GUI calls
 477 static wxCriticalSection *gs_critsectGui = NULL;
 478
 479 // critical section which protects gs_nWaitingForGui variable
 480 static wxCriticalSection *gs_critsectWaitingForGui = NULL;
 481
 482 // number of threads waiting for GUI in wxMutexGuiEnter()
 483 static size_t gs_nWaitingForGui = 0;
 484
 485 void wxOSXThreadModuleOnInit()
 486 {
 487     gs_critsectWaitingForGui = new wxCriticalSection();
 488     gs_critsectGui = new wxCriticalSection();
 489     gs_critsectGui->Enter();
 490 }
 491
 492
 493 void wxOSXThreadModuleOnExit()
 494 {
 495     if ( gs_critsectGui )
 496     {
 497         if ( !wxGuiOwnedByMainThread() )
 498         {
 499             gs_critsectGui->Enter();
 500             gs_bGuiOwnedByMainThread = true;
 501         }
 502
 503         gs_critsectGui->Leave();
 504         wxDELETE(gs_critsectGui);
 505     }
 506
 507     wxDELETE(gs_critsectWaitingForGui);
 508 }
 509
 510
 511 // wake up the main thread
 512 void WXDLLIMPEXP_BASE wxWakeUpMainThread()
 513 {
 514     wxMacWakeUp();
 515 }
 516
 517 void wxMutexGuiEnterImpl()
 518 {
 519     // this would dead lock everything...
 520     wxASSERT_MSG( !wxThread::IsMain(),
 521                  wxT("main thread doesn't want to block in wxMutexGuiEnter()!") );
 522
 523     // the order in which we enter the critical sections here is crucial!!
 524
 525     // set the flag telling to the main thread that we want to do some GUI
 526     {
 527         wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 528
 529         gs_nWaitingForGui++;
 530     }
 531
 532     wxWakeUpMainThread();
 533
 534     // now we may block here because the main thread will soon let us in
 535     // (during the next iteration of OnIdle())
 536     gs_critsectGui->Enter();
 537 }
 538
 539 void wxMutexGuiLeaveImpl()
 540 {
 541     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 542
 543     if ( wxThread::IsMain() )
 544     {
 545         gs_bGuiOwnedByMainThread = false;
 546     }
 547     else
 548     {
 549         // decrement the number of threads waiting for GUI access now
 550         wxASSERT_MSG( gs_nWaitingForGui > 0,
 551                      wxT("calling wxMutexGuiLeave() without entering it first?") );
 552
 553         gs_nWaitingForGui--;
 554
 555         wxWakeUpMainThread();
 556     }
 557
 558     gs_critsectGui->Leave();
 559 }
 560
 561 void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter()
 562 {
 563     wxASSERT_MSG( wxThread::IsMain(),
 564                  wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") );
 565
 566     if ( !gs_critsectWaitingForGui )
 567         return;
 568
 569     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 570
 571     if ( gs_nWaitingForGui == 0 )
 572     {
 573         // no threads are waiting for GUI - so we may acquire the lock without
 574         // any danger (but only if we don't already have it)
 575         if ( !wxGuiOwnedByMainThread() )
 576         {
 577             gs_critsectGui->Enter();
 578
 579             gs_bGuiOwnedByMainThread = true;
 580         }
 581         //else: already have it, nothing to do
 582     }
 583     else
 584     {
 585         // some threads are waiting, release the GUI lock if we have it
 586         if ( wxGuiOwnedByMainThread() )
 587             wxMutexGuiLeave();
 588         //else: some other worker thread is doing GUI
 589     }
 590 }
 591
 592 bool WXDLLIMPEXP_BASE wxGuiOwnedByMainThread()
 593 {
 594     return gs_bGuiOwnedByMainThread;
 595 }
 596
 597 #endif