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 #if wxUSE_EVENTLOOP_SOURCE
  29
  30 #ifndef WX_PRECOMP
  31     #include "wx/log.h"
  32     #include "wx/app.h"
  33 #endif
  34
  35 #include "wx/evtloopsrc.h"
  36
  37 #include "wx/scopedptr.h"
  38
  39 #include "wx/osx/private.h"
  40 #include "wx/osx/core/cfref.h"
  41 #include "wx/thread.h"
  42
  43 #if wxUSE_GUI
  44     #include "wx/nonownedwnd.h"
  45 #endif
  46
  47 // ============================================================================
  48 // wxCFEventLoopSource and wxCFEventLoop implementation
  49 // ============================================================================
  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 )
 167             wxTheApp->ProcessPendingEvents();
 168     }
 169
 170     if ( activity & kCFRunLoopBeforeWaiting )
 171     {
 172         if ( 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
 205     m_runLoop = CFGetCurrentRunLoop();
 206
 207     CFRunLoopObserverContext ctxt;
 208     bzero( &ctxt, sizeof(ctxt) );
 209     ctxt.info = this;
 210     m_commonModeRunLoopObserver = CFRunLoopObserverCreate( kCFAllocatorDefault, kCFRunLoopBeforeTimers | kCFRunLoopBeforeWaiting , true /* repeats */, 0,
 211                                                           (CFRunLoopObserverCallBack) wxCFEventLoop::OSXCommonModeObserverCallBack, &ctxt );
 212     CFRunLoopAddObserver(m_runLoop, m_commonModeRunLoopObserver, kCFRunLoopCommonModes);
 213     CFRelease(m_commonModeRunLoopObserver);
 214
 215     m_defaultModeRunLoopObserver = CFRunLoopObserverCreate( kCFAllocatorDefault, kCFRunLoopBeforeTimers | kCFRunLoopBeforeWaiting , true /* repeats */, 0,
 216                                                            (CFRunLoopObserverCallBack) wxCFEventLoop::OSXDefaultModeObserverCallBack, &ctxt );
 217     CFRunLoopAddObserver(m_runLoop, m_defaultModeRunLoopObserver, kCFRunLoopDefaultMode);
 218     CFRelease(m_defaultModeRunLoopObserver);
 219 }
 220
 221 wxCFEventLoop::~wxCFEventLoop()
 222 {
 223     CFRunLoopRemoveObserver(m_runLoop, m_commonModeRunLoopObserver, kCFRunLoopCommonModes);
 224     CFRunLoopRemoveObserver(m_runLoop, m_defaultModeRunLoopObserver, kCFRunLoopDefaultMode);
 225 }
 226
 227
 228 CFRunLoopRef wxCFEventLoop::CFGetCurrentRunLoop() const
 229 {
 230     return CFRunLoopGetCurrent();
 231 }
 232
 233 void wxCFEventLoop::WakeUp()
 234 {
 235     CFRunLoopWakeUp(m_runLoop);
 236 }
 237
 238 #if wxUSE_BASE
 239
 240 void wxMacWakeUp()
 241 {
 242     wxEventLoopBase * const loop = wxEventLoopBase::GetActive();
 243
 244     if ( loop )
 245         loop->WakeUp();
 246 }
 247
 248 #endif
 249
 250 bool wxCFEventLoop::YieldFor(long eventsToProcess)
 251 {
 252 #if wxUSE_THREADS
 253     // Yielding from a non-gui thread needs to bail out, otherwise we end up
 254     // possibly sending events in the thread too.
 255     if ( !wxThread::IsMain() )
 256     {
 257         return true;
 258     }
 259 #endif // wxUSE_THREADS
 260
 261     m_isInsideYield = true;
 262     m_eventsToProcessInsideYield = eventsToProcess;
 263
 264 #if wxUSE_LOG
 265     // disable log flushing from here because a call to wxYield() shouldn't
 266     // normally result in message boxes popping up &c
 267     wxLog::Suspend();
 268 #endif // wxUSE_LOG
 269
 270     // process all pending events:
 271     while ( DoProcessEvents() == 1 )
 272         ;
 273
 274     // it's necessary to call ProcessIdle() to update the frames sizes which
 275     // might have been changed (it also will update other things set from
 276     // OnUpdateUI() which is a nice (and desired) side effect)
 277     while ( ProcessIdle() ) {}
 278
 279     // if there are pending events, we must process them.
 280     if (wxTheApp)
 281         wxTheApp->ProcessPendingEvents();
 282
 283 #if wxUSE_LOG
 284     wxLog::Resume();
 285 #endif // wxUSE_LOG
 286     m_isInsideYield = false;
 287
 288     return true;
 289 }
 290
 291 // implement/override base class pure virtual
 292 bool wxCFEventLoop::Pending() const
 293 {
 294     return true;
 295 }
 296
 297 int wxCFEventLoop::DoProcessEvents()
 298 {
 299     return DispatchTimeout( 0 );
 300 }
 301
 302 bool wxCFEventLoop::Dispatch()
 303 {
 304     return DoProcessEvents() != 0;
 305 }
 306
 307 int wxCFEventLoop::DispatchTimeout(unsigned long timeout)
 308 {
 309     if ( !wxTheApp )
 310         return 0;
 311
 312     int status = DoDispatchTimeout(timeout);
 313
 314     switch( status )
 315     {
 316         case 0:
 317             break;
 318         case -1:
 319             if ( m_shouldExit )
 320                 return 0;
 321
 322             break;
 323         case 1:
 324             break;
 325     }
 326
 327     return status;
 328 }
 329
 330 int wxCFEventLoop::DoDispatchTimeout(unsigned long timeout)
 331 {
 332     SInt32 status = CFRunLoopRunInMode(kCFRunLoopDefaultMode, timeout / 1000.0 , true);
 333     switch( status )
 334     {
 335         case kCFRunLoopRunFinished:
 336             wxFAIL_MSG( "incorrect run loop state" );
 337             break;
 338         case kCFRunLoopRunStopped:
 339             return 0;
 340             break;
 341         case kCFRunLoopRunTimedOut:
 342             return -1;
 343             break;
 344         case kCFRunLoopRunHandledSource:
 345         default:
 346             break;
 347     }
 348     return 1;
 349 }
 350
 351 void wxCFEventLoop::DoRun()
 352 {
 353     for ( ;; )
 354     {
 355         // generate and process idle events for as long as we don't
 356         // have anything else to do
 357         DoProcessEvents();
 358
 359         // if the "should exit" flag is set, the loop should terminate
 360         // but not before processing any remaining messages so while
 361         // Pending() returns true, do process them
 362         if ( m_shouldExit )
 363         {
 364             while ( DoProcessEvents() == 1 )
 365                 ;
 366
 367             break;
 368         }
 369     }
 370 }
 371
 372 void wxCFEventLoop::DoStop()
 373 {
 374     CFRunLoopStop(CFGetCurrentRunLoop());
 375 }
 376
 377 // enters a loop calling OnNextIteration(), Pending() and Dispatch() and
 378 // terminating when Exit() is called
 379 int wxCFEventLoop::Run()
 380 {
 381     // event loops are not recursive, you need to create another loop!
 382     wxCHECK_MSG( !IsRunning(), -1, wxT("can't reenter a message loop") );
 383
 384     // ProcessIdle() and ProcessEvents() below may throw so the code here should
 385     // be exception-safe, hence we must use local objects for all actions we
 386     // should undo
 387     wxEventLoopActivator activate(this);
 388
 389     // we must ensure that OnExit() is called even if an exception is thrown
 390     // from inside ProcessEvents() but we must call it from Exit() in normal
 391     // situations because it is supposed to be called synchronously,
 392     // wxModalEventLoop depends on this (so we can't just use ON_BLOCK_EXIT or
 393     // something similar here)
 394 #if wxUSE_EXCEPTIONS
 395     for ( ;; )
 396     {
 397         try
 398         {
 399 #endif // wxUSE_EXCEPTIONS
 400
 401             DoRun();
 402
 403 #if wxUSE_EXCEPTIONS
 404             // exit the outer loop as well
 405             break;
 406         }
 407         catch ( ... )
 408         {
 409             try
 410             {
 411                 if ( !wxTheApp || !wxTheApp->OnExceptionInMainLoop() )
 412                 {
 413                     OnExit();
 414                     break;
 415                 }
 416                 //else: continue running the event loop
 417             }
 418             catch ( ... )
 419             {
 420                 // OnException() throwed, possibly rethrowing the same
 421                 // exception again: very good, but we still need OnExit() to
 422                 // be called
 423                 OnExit();
 424                 throw;
 425             }
 426         }
 427     }
 428 #endif // wxUSE_EXCEPTIONS
 429
 430     return m_exitcode;
 431 }
 432
 433 // sets the "should exit" flag and wakes up the loop so that it terminates
 434 // soon
 435 void wxCFEventLoop::Exit(int rc)
 436 {
 437     m_exitcode = rc;
 438     m_shouldExit = true;
 439     DoStop();
 440 }
 441
 442 // TODO Move to thread_osx.cpp
 443
 444 #if wxUSE_THREADS
 445
 446 // ----------------------------------------------------------------------------
 447 // GUI Serialization copied from MSW implementation
 448 // ----------------------------------------------------------------------------
 449
 450 // if it's false, some secondary thread is holding the GUI lock
 451 static bool gs_bGuiOwnedByMainThread = true;
 452
 453 // critical section which controls access to all GUI functions: any secondary
 454 // thread (i.e. except the main one) must enter this crit section before doing
 455 // any GUI calls
 456 static wxCriticalSection *gs_critsectGui = NULL;
 457
 458 // critical section which protects gs_nWaitingForGui variable
 459 static wxCriticalSection *gs_critsectWaitingForGui = NULL;
 460
 461 // number of threads waiting for GUI in wxMutexGuiEnter()
 462 static size_t gs_nWaitingForGui = 0;
 463
 464 void wxOSXThreadModuleOnInit()
 465 {
 466     gs_critsectWaitingForGui = new wxCriticalSection();
 467     gs_critsectGui = new wxCriticalSection();
 468     gs_critsectGui->Enter();
 469 }
 470
 471
 472 void wxOSXThreadModuleOnExit()
 473 {
 474     if ( gs_critsectGui )
 475     {
 476         if ( !wxGuiOwnedByMainThread() )
 477         {
 478             gs_critsectGui->Enter();
 479             gs_bGuiOwnedByMainThread = true;
 480         }
 481
 482         gs_critsectGui->Leave();
 483         wxDELETE(gs_critsectGui);
 484     }
 485
 486     wxDELETE(gs_critsectWaitingForGui);
 487 }
 488
 489
 490 // wake up the main thread
 491 void WXDLLIMPEXP_BASE wxWakeUpMainThread()
 492 {
 493     wxMacWakeUp();
 494 }
 495
 496 void wxMutexGuiEnterImpl()
 497 {
 498     // this would dead lock everything...
 499     wxASSERT_MSG( !wxThread::IsMain(),
 500                  wxT("main thread doesn't want to block in wxMutexGuiEnter()!") );
 501
 502     // the order in which we enter the critical sections here is crucial!!
 503
 504     // set the flag telling to the main thread that we want to do some GUI
 505     {
 506         wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 507
 508         gs_nWaitingForGui++;
 509     }
 510
 511     wxWakeUpMainThread();
 512
 513     // now we may block here because the main thread will soon let us in
 514     // (during the next iteration of OnIdle())
 515     gs_critsectGui->Enter();
 516 }
 517
 518 void wxMutexGuiLeaveImpl()
 519 {
 520     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 521
 522     if ( wxThread::IsMain() )
 523     {
 524         gs_bGuiOwnedByMainThread = false;
 525     }
 526     else
 527     {
 528         // decrement the number of threads waiting for GUI access now
 529         wxASSERT_MSG( gs_nWaitingForGui > 0,
 530                      wxT("calling wxMutexGuiLeave() without entering it first?") );
 531
 532         gs_nWaitingForGui--;
 533
 534         wxWakeUpMainThread();
 535     }
 536
 537     gs_critsectGui->Leave();
 538 }
 539
 540 void WXDLLIMPEXP_BASE wxMutexGuiLeaveOrEnter()
 541 {
 542     wxASSERT_MSG( wxThread::IsMain(),
 543                  wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") );
 544
 545     if ( !gs_critsectWaitingForGui )
 546         return;
 547
 548     wxCriticalSectionLocker enter(*gs_critsectWaitingForGui);
 549
 550     if ( gs_nWaitingForGui == 0 )
 551     {
 552         // no threads are waiting for GUI - so we may acquire the lock without
 553         // any danger (but only if we don't already have it)
 554         if ( !wxGuiOwnedByMainThread() )
 555         {
 556             gs_critsectGui->Enter();
 557
 558             gs_bGuiOwnedByMainThread = true;
 559         }
 560         //else: already have it, nothing to do
 561     }
 562     else
 563     {
 564         // some threads are waiting, release the GUI lock if we have it
 565         if ( wxGuiOwnedByMainThread() )
 566             wxMutexGuiLeave();
 567         //else: some other worker thread is doing GUI
 568     }
 569 }
 570
 571 bool WXDLLIMPEXP_BASE wxGuiOwnedByMainThread()
 572 {
 573     return gs_bGuiOwnedByMainThread;
 574 }
 575
 576 #endif