1 // Copyright (c) 2008 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "base/message_pump_mac.h"
7 #import <AppKit/AppKit.h>
8 #import <Foundation/Foundation.h>
9 #include <IOKit/IOMessage.h>
10 #include <IOKit/pwr_mgt/IOPMLib.h>
14 #import "base/chrome_application_mac.h"
15 #include "base/logging.h"
16 #include "base/time.h"
20 void NoOp(void* info) {
23 const CFTimeInterval kCFTimeIntervalMax =
24 std::numeric_limits<CFTimeInterval>::max();
30 // A scoper for autorelease pools created from message pump run loops.
31 // Avoids dirtying up the ScopedNSAutoreleasePool interface for the rare
32 // case where an autorelease pool needs to be passed in.
33 class MessagePumpScopedAutoreleasePool {
35 explicit MessagePumpScopedAutoreleasePool(MessagePumpCFRunLoopBase* pump) :
36 pool_(pump->CreateAutoreleasePool()) {
38 ~MessagePumpScopedAutoreleasePool() {
43 NSAutoreleasePool* pool_;
44 DISALLOW_COPY_AND_ASSIGN(MessagePumpScopedAutoreleasePool);
47 // Must be called on the run loop thread.
48 MessagePumpCFRunLoopBase::MessagePumpCFRunLoopBase()
50 delayed_work_fire_time_(kCFTimeIntervalMax),
52 run_nesting_level_(0),
53 deepest_nesting_level_(0),
54 delegateless_work_(false),
55 delegateless_delayed_work_(false),
56 delegateless_idle_work_(false) {
57 run_loop_ = CFRunLoopGetCurrent();
60 // Set a repeating timer with a preposterous firing time and interval. The
61 // timer will effectively never fire as-is. The firing time will be adjusted
62 // as needed when ScheduleDelayedWork is called.
63 CFRunLoopTimerContext timer_context = CFRunLoopTimerContext();
64 timer_context.info = this;
65 delayed_work_timer_ = CFRunLoopTimerCreate(NULL, // allocator
66 kCFTimeIntervalMax, // fire time
67 kCFTimeIntervalMax, // interval
72 CFRunLoopAddTimer(run_loop_, delayed_work_timer_, kCFRunLoopCommonModes);
74 CFRunLoopSourceContext source_context = CFRunLoopSourceContext();
75 source_context.info = this;
76 source_context.perform = RunWorkSource;
77 work_source_ = CFRunLoopSourceCreate(NULL, // allocator
80 CFRunLoopAddSource(run_loop_, work_source_, kCFRunLoopCommonModes);
82 source_context.perform = RunDelayedWorkSource;
83 delayed_work_source_ = CFRunLoopSourceCreate(NULL, // allocator
86 CFRunLoopAddSource(run_loop_, delayed_work_source_, kCFRunLoopCommonModes);
88 source_context.perform = RunIdleWorkSource;
89 idle_work_source_ = CFRunLoopSourceCreate(NULL, // allocator
92 CFRunLoopAddSource(run_loop_, idle_work_source_, kCFRunLoopCommonModes);
94 source_context.perform = RunNestingDeferredWorkSource;
95 nesting_deferred_work_source_ = CFRunLoopSourceCreate(NULL, // allocator
98 CFRunLoopAddSource(run_loop_, nesting_deferred_work_source_,
99 kCFRunLoopCommonModes);
101 CFRunLoopObserverContext observer_context = CFRunLoopObserverContext();
102 observer_context.info = this;
103 pre_wait_observer_ = CFRunLoopObserverCreate(NULL, // allocator
104 kCFRunLoopBeforeWaiting,
109 CFRunLoopAddObserver(run_loop_, pre_wait_observer_, kCFRunLoopCommonModes);
111 pre_source_observer_ = CFRunLoopObserverCreate(NULL, // allocator
112 kCFRunLoopBeforeSources,
117 CFRunLoopAddObserver(run_loop_, pre_source_observer_, kCFRunLoopCommonModes);
119 enter_exit_observer_ = CFRunLoopObserverCreate(NULL, // allocator
126 CFRunLoopAddObserver(run_loop_, enter_exit_observer_, kCFRunLoopCommonModes);
128 root_power_domain_ = IORegisterForSystemPower(this,
129 &power_notification_port_,
130 PowerStateNotification,
131 &power_notification_object_);
132 if (root_power_domain_ != MACH_PORT_NULL) {
135 IONotificationPortGetRunLoopSource(power_notification_port_),
136 kCFRunLoopCommonModes);
140 // Ideally called on the run loop thread. If other run loops were running
141 // lower on the run loop thread's stack when this object was created, the
142 // same number of run loops must be running when this object is destroyed.
143 MessagePumpCFRunLoopBase::~MessagePumpCFRunLoopBase() {
144 if (root_power_domain_ != MACH_PORT_NULL) {
145 CFRunLoopRemoveSource(
147 IONotificationPortGetRunLoopSource(power_notification_port_),
148 kCFRunLoopCommonModes);
149 IODeregisterForSystemPower(&power_notification_object_);
150 IOServiceClose(root_power_domain_);
151 IONotificationPortDestroy(power_notification_port_);
154 CFRunLoopRemoveObserver(run_loop_, enter_exit_observer_,
155 kCFRunLoopCommonModes);
156 CFRelease(enter_exit_observer_);
158 CFRunLoopRemoveObserver(run_loop_, pre_source_observer_,
159 kCFRunLoopCommonModes);
160 CFRelease(pre_source_observer_);
162 CFRunLoopRemoveObserver(run_loop_, pre_wait_observer_,
163 kCFRunLoopCommonModes);
164 CFRelease(pre_wait_observer_);
166 CFRunLoopRemoveSource(run_loop_, nesting_deferred_work_source_,
167 kCFRunLoopCommonModes);
168 CFRelease(nesting_deferred_work_source_);
170 CFRunLoopRemoveSource(run_loop_, idle_work_source_, kCFRunLoopCommonModes);
171 CFRelease(idle_work_source_);
173 CFRunLoopRemoveSource(run_loop_, delayed_work_source_, kCFRunLoopCommonModes);
174 CFRelease(delayed_work_source_);
176 CFRunLoopRemoveSource(run_loop_, work_source_, kCFRunLoopCommonModes);
177 CFRelease(work_source_);
179 CFRunLoopRemoveTimer(run_loop_, delayed_work_timer_, kCFRunLoopCommonModes);
180 CFRelease(delayed_work_timer_);
182 CFRelease(run_loop_);
185 // Must be called on the run loop thread.
186 void MessagePumpCFRunLoopBase::Run(Delegate* delegate) {
187 // nesting_level_ will be incremented in EnterExitRunLoop, so set
188 // run_nesting_level_ accordingly.
189 int last_run_nesting_level = run_nesting_level_;
190 run_nesting_level_ = nesting_level_ + 1;
192 Delegate* last_delegate = delegate_;
193 delegate_ = delegate;
196 // If any work showed up but could not be dispatched for want of a
197 // delegate, set it up for dispatch again now that a delegate is
199 if (delegateless_work_) {
200 CFRunLoopSourceSignal(work_source_);
201 delegateless_work_ = false;
203 if (delegateless_delayed_work_) {
204 CFRunLoopSourceSignal(delayed_work_source_);
205 delegateless_delayed_work_ = false;
207 if (delegateless_idle_work_) {
208 CFRunLoopSourceSignal(idle_work_source_);
209 delegateless_idle_work_ = false;
215 // Restore the previous state of the object.
216 delegate_ = last_delegate;
217 run_nesting_level_ = last_run_nesting_level;
220 // May be called on any thread.
221 void MessagePumpCFRunLoopBase::ScheduleWork() {
222 CFRunLoopSourceSignal(work_source_);
223 CFRunLoopWakeUp(run_loop_);
226 // Must be called on the run loop thread.
227 void MessagePumpCFRunLoopBase::ScheduleDelayedWork(
228 const Time& delayed_work_time) {
229 Time::Exploded exploded;
230 delayed_work_time.UTCExplode(&exploded);
231 double seconds = exploded.second +
232 (static_cast<double>((delayed_work_time.ToInternalValue()) %
233 Time::kMicrosecondsPerSecond) /
234 Time::kMicrosecondsPerSecond);
235 CFGregorianDate gregorian = {
238 exploded.day_of_month,
243 delayed_work_fire_time_ = CFGregorianDateGetAbsoluteTime(gregorian, NULL);
245 CFRunLoopTimerSetNextFireDate(delayed_work_timer_, delayed_work_fire_time_);
248 // Called from the run loop.
250 void MessagePumpCFRunLoopBase::RunDelayedWorkTimer(CFRunLoopTimerRef timer,
252 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
254 // The timer won't fire again until it's reset.
255 self->delayed_work_fire_time_ = kCFTimeIntervalMax;
257 // CFRunLoopTimers fire outside of the priority scheme for CFRunLoopSources.
258 // In order to establish the proper priority where delegate_->DoDelayedWork
259 // can only be called if delegate_->DoWork returns false, the timer used
260 // to schedule delayed work must signal a CFRunLoopSource set at a lower
261 // priority than the one used for delegate_->DoWork.
262 CFRunLoopSourceSignal(self->delayed_work_source_);
265 // Called from the run loop.
267 void MessagePumpCFRunLoopBase::RunWorkSource(void* info) {
268 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
272 // Called by MessagePumpCFRunLoopBase::RunWorkSource.
273 bool MessagePumpCFRunLoopBase::RunWork() {
275 // This point can be reached with a NULL delegate_ if Run is not on the
276 // stack but foreign code is spinning the CFRunLoop. Arrange to come back
277 // here when a delegate is available.
278 delegateless_work_ = true;
282 // The NSApplication-based run loop only drains the autorelease pool at each
283 // UI event (NSEvent). The autorelease pool is not drained for each
284 // CFRunLoopSource target that's run. Use a local pool for any autoreleased
285 // objects if the app is not currently handling a UI event to ensure they're
286 // released promptly even in the absence of UI events.
287 MessagePumpScopedAutoreleasePool autorelease_pool(this);
289 // Call DoWork once, and if something was done, arrange to come back here
290 // again as long as the loop is still running.
291 bool did_work = delegate_->DoWork();
293 CFRunLoopSourceSignal(work_source_);
299 // Called from the run loop.
301 void MessagePumpCFRunLoopBase::RunDelayedWorkSource(void* info) {
302 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
303 self->RunDelayedWork();
306 // Called by MessagePumpCFRunLoopBase::RunDelayedWorkSource.
307 bool MessagePumpCFRunLoopBase::RunDelayedWork() {
309 // This point can be reached with a NULL delegate_ if Run is not on the
310 // stack but foreign code is spinning the CFRunLoop. Arrange to come back
311 // here when a delegate is available.
312 delegateless_delayed_work_ = true;
316 // The NSApplication-based run loop only drains the autorelease pool at each
317 // UI event (NSEvent). The autorelease pool is not drained for each
318 // CFRunLoopSource target that's run. Use a local pool for any autoreleased
319 // objects if the app is not currently handling a UI event to ensure they're
320 // released promptly even in the absence of UI events.
321 MessagePumpScopedAutoreleasePool autorelease_pool(this);
324 delegate_->DoDelayedWork(&next_time);
326 bool more_work = !next_time.is_null();
328 TimeDelta delay = next_time - Time::Now();
329 if (delay > TimeDelta()) {
330 // There's more delayed work to be done in the future.
331 ScheduleDelayedWork(next_time);
333 // There's more delayed work to be done, and its time is in the past.
334 // Arrange to come back here directly as long as the loop is still
336 CFRunLoopSourceSignal(delayed_work_source_);
343 // Called from the run loop.
345 void MessagePumpCFRunLoopBase::RunIdleWorkSource(void* info) {
346 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
350 // Called by MessagePumpCFRunLoopBase::RunIdleWorkSource.
351 bool MessagePumpCFRunLoopBase::RunIdleWork() {
353 // This point can be reached with a NULL delegate_ if Run is not on the
354 // stack but foreign code is spinning the CFRunLoop. Arrange to come back
355 // here when a delegate is available.
356 delegateless_idle_work_ = true;
360 // The NSApplication-based run loop only drains the autorelease pool at each
361 // UI event (NSEvent). The autorelease pool is not drained for each
362 // CFRunLoopSource target that's run. Use a local pool for any autoreleased
363 // objects if the app is not currently handling a UI event to ensure they're
364 // released promptly even in the absence of UI events.
365 MessagePumpScopedAutoreleasePool autorelease_pool(this);
367 // Call DoIdleWork once, and if something was done, arrange to come back here
368 // again as long as the loop is still running.
369 bool did_work = delegate_->DoIdleWork();
371 CFRunLoopSourceSignal(idle_work_source_);
377 // Called from the run loop.
379 void MessagePumpCFRunLoopBase::RunNestingDeferredWorkSource(void* info) {
380 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
381 self->RunNestingDeferredWork();
384 // Called by MessagePumpCFRunLoopBase::RunNestingDeferredWorkSource.
385 bool MessagePumpCFRunLoopBase::RunNestingDeferredWork() {
387 // This point can be reached with a NULL delegate_ if Run is not on the
388 // stack but foreign code is spinning the CFRunLoop. There's no sense in
389 // attempting to do any work or signalling the work sources because
390 // without a delegate, work is not possible.
394 // Immediately try work in priority order.
396 if (!RunDelayedWork()) {
397 if (!RunIdleWork()) {
401 // There was no work, and delayed work was done. Arrange for the loop
402 // to try non-nestable idle work on a subsequent pass.
403 CFRunLoopSourceSignal(idle_work_source_);
406 // Work was done. Arrange for the loop to try non-nestable delayed and
407 // idle work on a subsequent pass.
408 CFRunLoopSourceSignal(delayed_work_source_);
409 CFRunLoopSourceSignal(idle_work_source_);
415 // Called before the run loop goes to sleep or exits, or processes sources.
416 void MessagePumpCFRunLoopBase::MaybeScheduleNestingDeferredWork() {
417 // deepest_nesting_level_ is set as run loops are entered. If the deepest
418 // level encountered is deeper than the current level, a nested loop
419 // (relative to the current level) ran since the last time nesting-deferred
420 // work was scheduled. When that situation is encountered, schedule
421 // nesting-deferred work in case any work was deferred because nested work
423 if (deepest_nesting_level_ > nesting_level_) {
424 deepest_nesting_level_ = nesting_level_;
425 CFRunLoopSourceSignal(nesting_deferred_work_source_);
429 // Called from the run loop.
431 void MessagePumpCFRunLoopBase::PreWaitObserver(CFRunLoopObserverRef observer,
432 CFRunLoopActivity activity,
434 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
436 // Attempt to do some idle work before going to sleep.
439 // The run loop is about to go to sleep. If any of the work done since it
440 // started or woke up resulted in a nested run loop running,
441 // nesting-deferred work may have accumulated. Schedule it for processing
443 self->MaybeScheduleNestingDeferredWork();
446 // Called from the run loop.
448 void MessagePumpCFRunLoopBase::PreSourceObserver(CFRunLoopObserverRef observer,
449 CFRunLoopActivity activity,
451 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
453 // The run loop has reached the top of the loop and is about to begin
454 // processing sources. If the last iteration of the loop at this nesting
455 // level did not sleep or exit, nesting-deferred work may have accumulated
456 // if a nested loop ran. Schedule nesting-deferred work for processing if
458 self->MaybeScheduleNestingDeferredWork();
461 // Called from the run loop.
463 void MessagePumpCFRunLoopBase::EnterExitObserver(CFRunLoopObserverRef observer,
464 CFRunLoopActivity activity,
466 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
469 case kCFRunLoopEntry:
470 ++self->nesting_level_;
471 if (self->nesting_level_ > self->deepest_nesting_level_) {
472 self->deepest_nesting_level_ = self->nesting_level_;
477 // Not all run loops go to sleep. If a run loop is stopped before it
478 // goes to sleep due to a CFRunLoopStop call, or if the timeout passed
479 // to CFRunLoopRunInMode expires, the run loop may proceed directly from
480 // handling sources to exiting without any sleep. This most commonly
481 // occurs when CFRunLoopRunInMode is passed a timeout of 0, causing it
482 // to make a single pass through the loop and exit without sleep. Some
483 // native loops use CFRunLoop in this way. Because PreWaitObserver will
484 // not be called in these case, MaybeScheduleNestingDeferredWork needs
485 // to be called here, as the run loop exits.
487 // MaybeScheduleNestingDeferredWork consults self->nesting_level_
488 // to determine whether to schedule nesting-deferred work. It expects
489 // the nesting level to be set to the depth of the loop that is going
490 // to sleep or exiting. It must be called before decrementing the
491 // value so that the value still corresponds to the level of the exiting
493 self->MaybeScheduleNestingDeferredWork();
494 --self->nesting_level_;
501 self->EnterExitRunLoop(activity);
504 // Called from the run loop.
506 void MessagePumpCFRunLoopBase::PowerStateNotification(void* info,
507 io_service_t service,
508 uint32_t message_type,
509 void* message_argument) {
510 // CFRunLoopTimer (NSTimer) is scheduled in terms of CFAbsoluteTime, which
511 // measures the number of seconds since 2001-01-01 00:00:00.0 Z. It is
512 // implemented in terms of kernel ticks, as in mach_absolute_time. While an
513 // offset and scale factor can be applied to convert between the two time
514 // bases at any time after boot, the kernel clock stops while the system is
515 // asleep, altering the offset. (The offset will also change when the
516 // real-time clock is adjusted.) CFRunLoopTimers are not readjusted to take
517 // this into account when the system wakes up, so any timers that were
518 // pending while the system was asleep will be delayed by the sleep
521 // The MessagePump interface assumes that scheduled delayed work will be
522 // performed at the time ScheduleDelayedWork was asked to perform it. The
523 // delay caused by the CFRunLoopTimer not firing at the appropriate time
524 // results in a stall of queued delayed work when the system wakes up.
525 // With this limitation, scheduled work would not be performed until
526 // (system wake time + scheduled work time - system sleep time), while it
527 // would be expected to be performed at (scheduled work time).
529 // To work around this problem, when the system wakes up from sleep, if a
530 // delayed work timer is pending, it is rescheduled to fire at the original
531 // time that it was scheduled to fire.
533 // This mechanism is not resilient if the real-time clock does not maintain
534 // stable time while the system is sleeping, but it matches the behavior of
535 // the various other MessagePump implementations, and MessageLoop seems to
536 // be limited in the same way.
539 // - Chris Kane, "NSTimer and deep sleep," cocoa-dev@lists.apple.com,
540 // http://lists.apple.com/archives/Cocoa-dev/2002/May/msg01547.html
541 // - Apple Technical Q&A QA1340, "Registering and unregistering for sleep
542 // and wake notifications,"
543 // http://developer.apple.com/mac/library/qa/qa2004/qa1340.html
544 // - Core Foundation source code, CF-550/CFRunLoop.c and CF-550/CFDate.c,
545 // http://www.opensource.apple.com/
547 MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
549 switch (message_type) {
550 case kIOMessageSystemWillPowerOn:
551 if (self->delayed_work_fire_time_ != kCFTimeIntervalMax) {
552 CFRunLoopTimerSetNextFireDate(self->delayed_work_timer_,
553 self->delayed_work_fire_time_);
557 case kIOMessageSystemWillSleep:
558 case kIOMessageCanSystemSleep:
559 // The system will wait for 30 seconds before entering sleep if neither
560 // IOAllowPowerChange nor IOCancelPowerChange are called. That would be
561 // pretty antisocial.
562 IOAllowPowerChange(self->root_power_domain_,
563 reinterpret_cast<long>(message_argument));
571 // Called by MessagePumpCFRunLoopBase::EnterExitRunLoop. The default
572 // implementation is a no-op.
573 void MessagePumpCFRunLoopBase::EnterExitRunLoop(CFRunLoopActivity activity) {
576 // Base version returns a standard NSAutoreleasePool.
577 NSAutoreleasePool* MessagePumpCFRunLoopBase::CreateAutoreleasePool() {
578 return [[NSAutoreleasePool alloc] init];
581 MessagePumpCFRunLoop::MessagePumpCFRunLoop()
582 : quit_pending_(false) {
585 // Called by MessagePumpCFRunLoopBase::DoRun. If other CFRunLoopRun loops were
586 // running lower on the run loop thread's stack when this object was created,
587 // the same number of CFRunLoopRun loops must be running for the outermost call
588 // to Run. Run/DoRun are reentrant after that point.
589 void MessagePumpCFRunLoop::DoRun(Delegate* delegate) {
590 // This is completely identical to calling CFRunLoopRun(), except autorelease
591 // pool management is introduced.
594 MessagePumpScopedAutoreleasePool autorelease_pool(this);
595 result = CFRunLoopRunInMode(kCFRunLoopDefaultMode,
598 } while (result != kCFRunLoopRunStopped && result != kCFRunLoopRunFinished);
601 // Must be called on the run loop thread.
602 void MessagePumpCFRunLoop::Quit() {
603 // Stop the innermost run loop managed by this MessagePumpCFRunLoop object.
604 if (nesting_level() == run_nesting_level()) {
605 // This object is running the innermost loop, just stop it.
606 CFRunLoopStop(run_loop());
608 // There's another loop running inside the loop managed by this object.
609 // In other words, someone else called CFRunLoopRunInMode on the same
610 // thread, deeper on the stack than the deepest Run call. Don't preempt
611 // other run loops, just mark this object to quit the innermost Run as
612 // soon as the other inner loops not managed by Run are done.
613 quit_pending_ = true;
617 // Called by MessagePumpCFRunLoopBase::EnterExitObserver.
618 void MessagePumpCFRunLoop::EnterExitRunLoop(CFRunLoopActivity activity) {
619 if (activity == kCFRunLoopExit &&
620 nesting_level() == run_nesting_level() &&
622 // Quit was called while loops other than those managed by this object
623 // were running further inside a run loop managed by this object. Now
624 // that all unmanaged inner run loops are gone, stop the loop running
626 CFRunLoopStop(run_loop());
627 quit_pending_ = false;
631 MessagePumpNSRunLoop::MessagePumpNSRunLoop()
632 : keep_running_(true) {
633 CFRunLoopSourceContext source_context = CFRunLoopSourceContext();
634 source_context.perform = NoOp;
635 quit_source_ = CFRunLoopSourceCreate(NULL, // allocator
638 CFRunLoopAddSource(run_loop(), quit_source_, kCFRunLoopCommonModes);
641 MessagePumpNSRunLoop::~MessagePumpNSRunLoop() {
642 CFRunLoopRemoveSource(run_loop(), quit_source_, kCFRunLoopCommonModes);
643 CFRelease(quit_source_);
646 void MessagePumpNSRunLoop::DoRun(Delegate* delegate) {
647 while (keep_running_) {
648 // NSRunLoop manages autorelease pools itself.
649 [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode
650 beforeDate:[NSDate distantFuture]];
653 keep_running_ = true;
656 void MessagePumpNSRunLoop::Quit() {
657 keep_running_ = false;
658 CFRunLoopSourceSignal(quit_source_);
659 CFRunLoopWakeUp(run_loop());
662 MessagePumpNSApplication::MessagePumpNSApplication()
663 : keep_running_(true),
664 running_own_loop_(false) {
667 void MessagePumpNSApplication::DoRun(Delegate* delegate) {
668 bool last_running_own_loop_ = running_own_loop_;
670 // TODO(dmaclach): Get rid of this gratuitous sharedApplication.
671 // Tests should be setting up their applications on their own.
672 [CrApplication sharedApplication];
674 if (![NSApp isRunning]) {
675 running_own_loop_ = false;
676 // NSApplication manages autorelease pools itself when run this way.
679 running_own_loop_ = true;
680 NSDate* distant_future = [NSDate distantFuture];
681 while (keep_running_) {
682 MessagePumpScopedAutoreleasePool autorelease_pool(this);
683 NSEvent* event = [NSApp nextEventMatchingMask:NSAnyEventMask
684 untilDate:distant_future
685 inMode:NSDefaultRunLoopMode
688 [NSApp sendEvent:event];
691 keep_running_ = true;
694 running_own_loop_ = last_running_own_loop_;
697 void MessagePumpNSApplication::Quit() {
698 if (!running_own_loop_) {
701 keep_running_ = false;
704 // Send a fake event to wake the loop up.
705 [NSApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined
706 location:NSMakePoint(0, 0)
717 // Prevents an autorelease pool from being created if the app is in the midst of
718 // handling a UI event because various parts of AppKit depend on objects that
719 // are created while handling a UI event to be autoreleased in the event loop.
720 // An example of this is NSWindowController. When a window with a window
721 // controller is closed it goes through a stack like this:
722 // (Several stack frames elided for clarity)
724 // #0 [NSWindowController autorelease]
726 // #2 MessagePumpCFRunLoopBase::DoWork()
727 // #3 [NSRunLoop run]
728 // #4 [NSButton performClick:]
729 // #5 [NSWindow sendEvent:]
730 // #6 [NSApp sendEvent:]
733 // -performClick: spins a nested run loop. If the pool created in DoWork was a
734 // standard NSAutoreleasePool, it would release the objects that were
735 // autoreleased into it once DoWork released it. This would cause the window
736 // controller, which autoreleased itself in frame #0, to release itself, and
737 // possibly free itself. Unfortunately this window controller controls the
738 // window in frame #5. When the stack is unwound to frame #5, the window would
739 // no longer exists and crashes may occur. Apple gets around this by never
740 // releasing the pool it creates in frame #4, and letting frame #7 clean it up
741 // when it cleans up the pool that wraps frame #7. When an autorelease pool is
742 // released it releases all other pools that were created after it on the
743 // autorelease pool stack.
745 // CrApplication is responsible for setting handlingSendEvent to true just
746 // before it sends the event throught the event handling mechanism, and
747 // returning it to its previous value once the event has been sent.
748 NSAutoreleasePool* MessagePumpNSApplication::CreateAutoreleasePool() {
749 NSAutoreleasePool* pool = nil;
750 DCHECK([NSApp isKindOfClass:[CrApplication class]]);
751 if (![static_cast<CrApplication*>(NSApp) isHandlingSendEvent]) {
752 pool = MessagePumpCFRunLoopBase::CreateAutoreleasePool();
758 MessagePump* MessagePumpMac::Create() {
759 if ([NSThread isMainThread]) {
760 return new MessagePumpNSApplication;
763 return new MessagePumpNSRunLoop;