// Copyright (c) 2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/message_pump_mac.h"
#import <AppKit/AppKit.h>
#import <Foundation/Foundation.h>
#include <IOKit/IOMessage.h>
#include <IOKit/pwr_mgt/IOPMLib.h>
#include <limits>
#import "base/chrome_application_mac.h"
#include "base/logging.h"
#include "base/time.h"
namespace {
void NoOp(void* info) {
}
const CFTimeInterval kCFTimeIntervalMax =
std::numeric_limits<CFTimeInterval>::max();
} // namespace
namespace base {
// A scoper for autorelease pools created from message pump run loops.
// Avoids dirtying up the ScopedNSAutoreleasePool interface for the rare
// case where an autorelease pool needs to be passed in.
class MessagePumpScopedAutoreleasePool {
public:
explicit MessagePumpScopedAutoreleasePool(MessagePumpCFRunLoopBase* pump) :
pool_(pump->CreateAutoreleasePool()) {
}
~MessagePumpScopedAutoreleasePool() {
[pool_ drain];
}
private:
NSAutoreleasePool* pool_;
DISALLOW_COPY_AND_ASSIGN(MessagePumpScopedAutoreleasePool);
};
// Must be called on the run loop thread.
MessagePumpCFRunLoopBase::MessagePumpCFRunLoopBase()
: delegate_(NULL),
delayed_work_fire_time_(kCFTimeIntervalMax),
nesting_level_(0),
run_nesting_level_(0),
deepest_nesting_level_(0),
delegateless_work_(false),
delegateless_delayed_work_(false),
delegateless_idle_work_(false) {
run_loop_ = CFRunLoopGetCurrent();
CFRetain(run_loop_);
// Set a repeating timer with a preposterous firing time and interval. The
// timer will effectively never fire as-is. The firing time will be adjusted
// as needed when ScheduleDelayedWork is called.
CFRunLoopTimerContext timer_context = CFRunLoopTimerContext();
timer_context.info = this;
delayed_work_timer_ = CFRunLoopTimerCreate(NULL, // allocator
kCFTimeIntervalMax, // fire time
kCFTimeIntervalMax, // interval
0, // flags
0, // priority
RunDelayedWorkTimer,
&timer_context);
CFRunLoopAddTimer(run_loop_, delayed_work_timer_, kCFRunLoopCommonModes);
CFRunLoopSourceContext source_context = CFRunLoopSourceContext();
source_context.info = this;
source_context.perform = RunWorkSource;
work_source_ = CFRunLoopSourceCreate(NULL, // allocator
1, // priority
&source_context);
CFRunLoopAddSource(run_loop_, work_source_, kCFRunLoopCommonModes);
source_context.perform = RunDelayedWorkSource;
delayed_work_source_ = CFRunLoopSourceCreate(NULL, // allocator
2, // priority
&source_context);
CFRunLoopAddSource(run_loop_, delayed_work_source_, kCFRunLoopCommonModes);
source_context.perform = RunIdleWorkSource;
idle_work_source_ = CFRunLoopSourceCreate(NULL, // allocator
3, // priority
&source_context);
CFRunLoopAddSource(run_loop_, idle_work_source_, kCFRunLoopCommonModes);
source_context.perform = RunNestingDeferredWorkSource;
nesting_deferred_work_source_ = CFRunLoopSourceCreate(NULL, // allocator
0, // priority
&source_context);
CFRunLoopAddSource(run_loop_, nesting_deferred_work_source_,
kCFRunLoopCommonModes);
CFRunLoopObserverContext observer_context = CFRunLoopObserverContext();
observer_context.info = this;
pre_wait_observer_ = CFRunLoopObserverCreate(NULL, // allocator
kCFRunLoopBeforeWaiting,
true, // repeat
0, // priority
PreWaitObserver,
&observer_context);
CFRunLoopAddObserver(run_loop_, pre_wait_observer_, kCFRunLoopCommonModes);
pre_source_observer_ = CFRunLoopObserverCreate(NULL, // allocator
kCFRunLoopBeforeSources,
true, // repeat
0, // priority
PreSourceObserver,
&observer_context);
CFRunLoopAddObserver(run_loop_, pre_source_observer_, kCFRunLoopCommonModes);
enter_exit_observer_ = CFRunLoopObserverCreate(NULL, // allocator
kCFRunLoopEntry |
kCFRunLoopExit,
true, // repeat
0, // priority
EnterExitObserver,
&observer_context);
CFRunLoopAddObserver(run_loop_, enter_exit_observer_, kCFRunLoopCommonModes);
root_power_domain_ = IORegisterForSystemPower(this,
&power_notification_port_,
PowerStateNotification,
&power_notification_object_);
if (root_power_domain_ != MACH_PORT_NULL) {
CFRunLoopAddSource(
run_loop_,
IONotificationPortGetRunLoopSource(power_notification_port_),
kCFRunLoopCommonModes);
}
}
// Ideally called on the run loop thread. If other run loops were running
// lower on the run loop thread's stack when this object was created, the
// same number of run loops must be running when this object is destroyed.
MessagePumpCFRunLoopBase::~MessagePumpCFRunLoopBase() {
if (root_power_domain_ != MACH_PORT_NULL) {
CFRunLoopRemoveSource(
run_loop_,
IONotificationPortGetRunLoopSource(power_notification_port_),
kCFRunLoopCommonModes);
IODeregisterForSystemPower(&power_notification_object_);
IOServiceClose(root_power_domain_);
IONotificationPortDestroy(power_notification_port_);
}
CFRunLoopRemoveObserver(run_loop_, enter_exit_observer_,
kCFRunLoopCommonModes);
CFRelease(enter_exit_observer_);
CFRunLoopRemoveObserver(run_loop_, pre_source_observer_,
kCFRunLoopCommonModes);
CFRelease(pre_source_observer_);
CFRunLoopRemoveObserver(run_loop_, pre_wait_observer_,
kCFRunLoopCommonModes);
CFRelease(pre_wait_observer_);
CFRunLoopRemoveSource(run_loop_, nesting_deferred_work_source_,
kCFRunLoopCommonModes);
CFRelease(nesting_deferred_work_source_);
CFRunLoopRemoveSource(run_loop_, idle_work_source_, kCFRunLoopCommonModes);
CFRelease(idle_work_source_);
CFRunLoopRemoveSource(run_loop_, delayed_work_source_, kCFRunLoopCommonModes);
CFRelease(delayed_work_source_);
CFRunLoopRemoveSource(run_loop_, work_source_, kCFRunLoopCommonModes);
CFRelease(work_source_);
CFRunLoopRemoveTimer(run_loop_, delayed_work_timer_, kCFRunLoopCommonModes);
CFRelease(delayed_work_timer_);
CFRelease(run_loop_);
}
// Must be called on the run loop thread.
void MessagePumpCFRunLoopBase::Run(Delegate* delegate) {
// nesting_level_ will be incremented in EnterExitRunLoop, so set
// run_nesting_level_ accordingly.
int last_run_nesting_level = run_nesting_level_;
run_nesting_level_ = nesting_level_ + 1;
Delegate* last_delegate = delegate_;
delegate_ = delegate;
if (delegate) {
// If any work showed up but could not be dispatched for want of a
// delegate, set it up for dispatch again now that a delegate is
// available.
if (delegateless_work_) {
CFRunLoopSourceSignal(work_source_);
delegateless_work_ = false;
}
if (delegateless_delayed_work_) {
CFRunLoopSourceSignal(delayed_work_source_);
delegateless_delayed_work_ = false;
}
if (delegateless_idle_work_) {
CFRunLoopSourceSignal(idle_work_source_);
delegateless_idle_work_ = false;
}
}
DoRun(delegate);
// Restore the previous state of the object.
delegate_ = last_delegate;
run_nesting_level_ = last_run_nesting_level;
}
// May be called on any thread.
void MessagePumpCFRunLoopBase::ScheduleWork() {
CFRunLoopSourceSignal(work_source_);
CFRunLoopWakeUp(run_loop_);
}
// Must be called on the run loop thread.
void MessagePumpCFRunLoopBase::ScheduleDelayedWork(
const Time& delayed_work_time) {
Time::Exploded exploded;
delayed_work_time.UTCExplode(&exploded);
double seconds = exploded.second +
(static_cast<double>((delayed_work_time.ToInternalValue()) %
Time::kMicrosecondsPerSecond) /
Time::kMicrosecondsPerSecond);
CFGregorianDate gregorian = {
exploded.year,
exploded.month,
exploded.day_of_month,
exploded.hour,
exploded.minute,
seconds
};
delayed_work_fire_time_ = CFGregorianDateGetAbsoluteTime(gregorian, NULL);
CFRunLoopTimerSetNextFireDate(delayed_work_timer_, delayed_work_fire_time_);
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::RunDelayedWorkTimer(CFRunLoopTimerRef timer,
void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
// The timer won't fire again until it's reset.
self->delayed_work_fire_time_ = kCFTimeIntervalMax;
// CFRunLoopTimers fire outside of the priority scheme for CFRunLoopSources.
// In order to establish the proper priority where delegate_->DoDelayedWork
// can only be called if delegate_->DoWork returns false, the timer used
// to schedule delayed work must signal a CFRunLoopSource set at a lower
// priority than the one used for delegate_->DoWork.
CFRunLoopSourceSignal(self->delayed_work_source_);
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::RunWorkSource(void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
self->RunWork();
}
// Called by MessagePumpCFRunLoopBase::RunWorkSource.
bool MessagePumpCFRunLoopBase::RunWork() {
if (!delegate_) {
// This point can be reached with a NULL delegate_ if Run is not on the
// stack but foreign code is spinning the CFRunLoop. Arrange to come back
// here when a delegate is available.
delegateless_work_ = true;
return false;
}
// The NSApplication-based run loop only drains the autorelease pool at each
// UI event (NSEvent). The autorelease pool is not drained for each
// CFRunLoopSource target that's run. Use a local pool for any autoreleased
// objects if the app is not currently handling a UI event to ensure they're
// released promptly even in the absence of UI events.
MessagePumpScopedAutoreleasePool autorelease_pool(this);
// Call DoWork once, and if something was done, arrange to come back here
// again as long as the loop is still running.
bool did_work = delegate_->DoWork();
if (did_work) {
CFRunLoopSourceSignal(work_source_);
}
return did_work;
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::RunDelayedWorkSource(void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
self->RunDelayedWork();
}
// Called by MessagePumpCFRunLoopBase::RunDelayedWorkSource.
bool MessagePumpCFRunLoopBase::RunDelayedWork() {
if (!delegate_) {
// This point can be reached with a NULL delegate_ if Run is not on the
// stack but foreign code is spinning the CFRunLoop. Arrange to come back
// here when a delegate is available.
delegateless_delayed_work_ = true;
return false;
}
// The NSApplication-based run loop only drains the autorelease pool at each
// UI event (NSEvent). The autorelease pool is not drained for each
// CFRunLoopSource target that's run. Use a local pool for any autoreleased
// objects if the app is not currently handling a UI event to ensure they're
// released promptly even in the absence of UI events.
MessagePumpScopedAutoreleasePool autorelease_pool(this);
Time next_time;
delegate_->DoDelayedWork(&next_time);
bool more_work = !next_time.is_null();
if (more_work) {
TimeDelta delay = next_time - Time::Now();
if (delay > TimeDelta()) {
// There's more delayed work to be done in the future.
ScheduleDelayedWork(next_time);
} else {
// There's more delayed work to be done, and its time is in the past.
// Arrange to come back here directly as long as the loop is still
// running.
CFRunLoopSourceSignal(delayed_work_source_);
}
}
return more_work;
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::RunIdleWorkSource(void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
self->RunIdleWork();
}
// Called by MessagePumpCFRunLoopBase::RunIdleWorkSource.
bool MessagePumpCFRunLoopBase::RunIdleWork() {
if (!delegate_) {
// This point can be reached with a NULL delegate_ if Run is not on the
// stack but foreign code is spinning the CFRunLoop. Arrange to come back
// here when a delegate is available.
delegateless_idle_work_ = true;
return false;
}
// The NSApplication-based run loop only drains the autorelease pool at each
// UI event (NSEvent). The autorelease pool is not drained for each
// CFRunLoopSource target that's run. Use a local pool for any autoreleased
// objects if the app is not currently handling a UI event to ensure they're
// released promptly even in the absence of UI events.
MessagePumpScopedAutoreleasePool autorelease_pool(this);
// Call DoIdleWork once, and if something was done, arrange to come back here
// again as long as the loop is still running.
bool did_work = delegate_->DoIdleWork();
if (did_work) {
CFRunLoopSourceSignal(idle_work_source_);
}
return did_work;
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::RunNestingDeferredWorkSource(void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
self->RunNestingDeferredWork();
}
// Called by MessagePumpCFRunLoopBase::RunNestingDeferredWorkSource.
bool MessagePumpCFRunLoopBase::RunNestingDeferredWork() {
if (!delegate_) {
// This point can be reached with a NULL delegate_ if Run is not on the
// stack but foreign code is spinning the CFRunLoop. There's no sense in
// attempting to do any work or signalling the work sources because
// without a delegate, work is not possible.
return false;
}
// Immediately try work in priority order.
if (!RunWork()) {
if (!RunDelayedWork()) {
if (!RunIdleWork()) {
return false;
}
} else {
// There was no work, and delayed work was done. Arrange for the loop
// to try non-nestable idle work on a subsequent pass.
CFRunLoopSourceSignal(idle_work_source_);
}
} else {
// Work was done. Arrange for the loop to try non-nestable delayed and
// idle work on a subsequent pass.
CFRunLoopSourceSignal(delayed_work_source_);
CFRunLoopSourceSignal(idle_work_source_);
}
return true;
}
// Called before the run loop goes to sleep or exits, or processes sources.
void MessagePumpCFRunLoopBase::MaybeScheduleNestingDeferredWork() {
// deepest_nesting_level_ is set as run loops are entered. If the deepest
// level encountered is deeper than the current level, a nested loop
// (relative to the current level) ran since the last time nesting-deferred
// work was scheduled. When that situation is encountered, schedule
// nesting-deferred work in case any work was deferred because nested work
// was disallowed.
if (deepest_nesting_level_ > nesting_level_) {
deepest_nesting_level_ = nesting_level_;
CFRunLoopSourceSignal(nesting_deferred_work_source_);
}
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::PreWaitObserver(CFRunLoopObserverRef observer,
CFRunLoopActivity activity,
void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
// Attempt to do some idle work before going to sleep.
self->RunIdleWork();
// The run loop is about to go to sleep. If any of the work done since it
// started or woke up resulted in a nested run loop running,
// nesting-deferred work may have accumulated. Schedule it for processing
// if appropriate.
self->MaybeScheduleNestingDeferredWork();
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::PreSourceObserver(CFRunLoopObserverRef observer,
CFRunLoopActivity activity,
void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
// The run loop has reached the top of the loop and is about to begin
// processing sources. If the last iteration of the loop at this nesting
// level did not sleep or exit, nesting-deferred work may have accumulated
// if a nested loop ran. Schedule nesting-deferred work for processing if
// appropriate.
self->MaybeScheduleNestingDeferredWork();
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::EnterExitObserver(CFRunLoopObserverRef observer,
CFRunLoopActivity activity,
void* info) {
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
switch (activity) {
case kCFRunLoopEntry:
++self->nesting_level_;
if (self->nesting_level_ > self->deepest_nesting_level_) {
self->deepest_nesting_level_ = self->nesting_level_;
}
break;
case kCFRunLoopExit:
// Not all run loops go to sleep. If a run loop is stopped before it
// goes to sleep due to a CFRunLoopStop call, or if the timeout passed
// to CFRunLoopRunInMode expires, the run loop may proceed directly from
// handling sources to exiting without any sleep. This most commonly
// occurs when CFRunLoopRunInMode is passed a timeout of 0, causing it
// to make a single pass through the loop and exit without sleep. Some
// native loops use CFRunLoop in this way. Because PreWaitObserver will
// not be called in these case, MaybeScheduleNestingDeferredWork needs
// to be called here, as the run loop exits.
//
// MaybeScheduleNestingDeferredWork consults self->nesting_level_
// to determine whether to schedule nesting-deferred work. It expects
// the nesting level to be set to the depth of the loop that is going
// to sleep or exiting. It must be called before decrementing the
// value so that the value still corresponds to the level of the exiting
// loop.
self->MaybeScheduleNestingDeferredWork();
--self->nesting_level_;
break;
default:
break;
}
self->EnterExitRunLoop(activity);
}
// Called from the run loop.
// static
void MessagePumpCFRunLoopBase::PowerStateNotification(void* info,
io_service_t service,
uint32_t message_type,
void* message_argument) {
// CFRunLoopTimer (NSTimer) is scheduled in terms of CFAbsoluteTime, which
// measures the number of seconds since 2001-01-01 00:00:00.0 Z. It is
// implemented in terms of kernel ticks, as in mach_absolute_time. While an
// offset and scale factor can be applied to convert between the two time
// bases at any time after boot, the kernel clock stops while the system is
// asleep, altering the offset. (The offset will also change when the
// real-time clock is adjusted.) CFRunLoopTimers are not readjusted to take
// this into account when the system wakes up, so any timers that were
// pending while the system was asleep will be delayed by the sleep
// duration.
//
// The MessagePump interface assumes that scheduled delayed work will be
// performed at the time ScheduleDelayedWork was asked to perform it. The
// delay caused by the CFRunLoopTimer not firing at the appropriate time
// results in a stall of queued delayed work when the system wakes up.
// With this limitation, scheduled work would not be performed until
// (system wake time + scheduled work time - system sleep time), while it
// would be expected to be performed at (scheduled work time).
//
// To work around this problem, when the system wakes up from sleep, if a
// delayed work timer is pending, it is rescheduled to fire at the original
// time that it was scheduled to fire.
//
// This mechanism is not resilient if the real-time clock does not maintain
// stable time while the system is sleeping, but it matches the behavior of
// the various other MessagePump implementations, and MessageLoop seems to
// be limited in the same way.
//
// References
// - Chris Kane, "NSTimer and deep sleep," cocoa-dev@lists.apple.com,
// http://lists.apple.com/archives/Cocoa-dev/2002/May/msg01547.html
// - Apple Technical Q&A QA1340, "Registering and unregistering for sleep
// and wake notifications,"
// http://developer.apple.com/mac/library/qa/qa2004/qa1340.html
// - Core Foundation source code, CF-550/CFRunLoop.c and CF-550/CFDate.c,
// http://www.opensource.apple.com/
MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
switch (message_type) {
case kIOMessageSystemWillPowerOn:
if (self->delayed_work_fire_time_ != kCFTimeIntervalMax) {
CFRunLoopTimerSetNextFireDate(self->delayed_work_timer_,
self->delayed_work_fire_time_);
}
break;
case kIOMessageSystemWillSleep:
case kIOMessageCanSystemSleep:
// The system will wait for 30 seconds before entering sleep if neither
// IOAllowPowerChange nor IOCancelPowerChange are called. That would be
// pretty antisocial.
IOAllowPowerChange(self->root_power_domain_,
reinterpret_cast<long>(message_argument));
break;
default:
break;
}
}
// Called by MessagePumpCFRunLoopBase::EnterExitRunLoop. The default
// implementation is a no-op.
void MessagePumpCFRunLoopBase::EnterExitRunLoop(CFRunLoopActivity activity) {
}
// Base version returns a standard NSAutoreleasePool.
NSAutoreleasePool* MessagePumpCFRunLoopBase::CreateAutoreleasePool() {
return [[NSAutoreleasePool alloc] init];
}
MessagePumpCFRunLoop::MessagePumpCFRunLoop()
: quit_pending_(false) {
}
// Called by MessagePumpCFRunLoopBase::DoRun. If other CFRunLoopRun loops were
// running lower on the run loop thread's stack when this object was created,
// the same number of CFRunLoopRun loops must be running for the outermost call
// to Run. Run/DoRun are reentrant after that point.
void MessagePumpCFRunLoop::DoRun(Delegate* delegate) {
// This is completely identical to calling CFRunLoopRun(), except autorelease
// pool management is introduced.
int result;
do {
MessagePumpScopedAutoreleasePool autorelease_pool(this);
result = CFRunLoopRunInMode(kCFRunLoopDefaultMode,
kCFTimeIntervalMax,
false);
} while (result != kCFRunLoopRunStopped && result != kCFRunLoopRunFinished);
}
// Must be called on the run loop thread.
void MessagePumpCFRunLoop::Quit() {
// Stop the innermost run loop managed by this MessagePumpCFRunLoop object.
if (nesting_level() == run_nesting_level()) {
// This object is running the innermost loop, just stop it.
CFRunLoopStop(run_loop());
} else {
// There's another loop running inside the loop managed by this object.
// In other words, someone else called CFRunLoopRunInMode on the same
// thread, deeper on the stack than the deepest Run call. Don't preempt
// other run loops, just mark this object to quit the innermost Run as
// soon as the other inner loops not managed by Run are done.
quit_pending_ = true;
}
}
// Called by MessagePumpCFRunLoopBase::EnterExitObserver.
void MessagePumpCFRunLoop::EnterExitRunLoop(CFRunLoopActivity activity) {
if (activity == kCFRunLoopExit &&
nesting_level() == run_nesting_level() &&
quit_pending_) {
// Quit was called while loops other than those managed by this object
// were running further inside a run loop managed by this object. Now
// that all unmanaged inner run loops are gone, stop the loop running
// just inside Run.
CFRunLoopStop(run_loop());
quit_pending_ = false;
}
}
MessagePumpNSRunLoop::MessagePumpNSRunLoop()
: keep_running_(true) {
CFRunLoopSourceContext source_context = CFRunLoopSourceContext();
source_context.perform = NoOp;
quit_source_ = CFRunLoopSourceCreate(NULL, // allocator
0, // priority
&source_context);
CFRunLoopAddSource(run_loop(), quit_source_, kCFRunLoopCommonModes);
}
MessagePumpNSRunLoop::~MessagePumpNSRunLoop() {
CFRunLoopRemoveSource(run_loop(), quit_source_, kCFRunLoopCommonModes);
CFRelease(quit_source_);
}
void MessagePumpNSRunLoop::DoRun(Delegate* delegate) {
while (keep_running_) {
// NSRunLoop manages autorelease pools itself.
[[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode
beforeDate:[NSDate distantFuture]];
}
keep_running_ = true;
}
void MessagePumpNSRunLoop::Quit() {
keep_running_ = false;
CFRunLoopSourceSignal(quit_source_);
CFRunLoopWakeUp(run_loop());
}
MessagePumpNSApplication::MessagePumpNSApplication()
: keep_running_(true),
running_own_loop_(false) {
}
void MessagePumpNSApplication::DoRun(Delegate* delegate) {
bool last_running_own_loop_ = running_own_loop_;
// TODO(dmaclach): Get rid of this gratuitous sharedApplication.
// Tests should be setting up their applications on their own.
[CrApplication sharedApplication];
if (![NSApp isRunning]) {
running_own_loop_ = false;
// NSApplication manages autorelease pools itself when run this way.
[NSApp run];
} else {
running_own_loop_ = true;
NSDate* distant_future = [NSDate distantFuture];
while (keep_running_) {
MessagePumpScopedAutoreleasePool autorelease_pool(this);
NSEvent* event = [NSApp nextEventMatchingMask:NSAnyEventMask
untilDate:distant_future
inMode:NSDefaultRunLoopMode
dequeue:YES];
if (event) {
[NSApp sendEvent:event];
}
}
keep_running_ = true;
}
running_own_loop_ = last_running_own_loop_;
}
void MessagePumpNSApplication::Quit() {
if (!running_own_loop_) {
[NSApp stop:nil];
} else {
keep_running_ = false;
}
// Send a fake event to wake the loop up.
[NSApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined
location:NSMakePoint(0, 0)
modifierFlags:0
timestamp:0
windowNumber:0
context:NULL
subtype:0
data1:0
data2:0]
atStart:NO];
}
// Prevents an autorelease pool from being created if the app is in the midst of
// handling a UI event because various parts of AppKit depend on objects that
// are created while handling a UI event to be autoreleased in the event loop.
// An example of this is NSWindowController. When a window with a window
// controller is closed it goes through a stack like this:
// (Several stack frames elided for clarity)
//
// #0 [NSWindowController autorelease]
// #1 DoAClose
// #2 MessagePumpCFRunLoopBase::DoWork()
// #3 [NSRunLoop run]
// #4 [NSButton performClick:]
// #5 [NSWindow sendEvent:]
// #6 [NSApp sendEvent:]
// #7 [NSApp run]
//
// -performClick: spins a nested run loop. If the pool created in DoWork was a
// standard NSAutoreleasePool, it would release the objects that were
// autoreleased into it once DoWork released it. This would cause the window
// controller, which autoreleased itself in frame #0, to release itself, and
// possibly free itself. Unfortunately this window controller controls the
// window in frame #5. When the stack is unwound to frame #5, the window would
// no longer exists and crashes may occur. Apple gets around this by never
// releasing the pool it creates in frame #4, and letting frame #7 clean it up
// when it cleans up the pool that wraps frame #7. When an autorelease pool is
// released it releases all other pools that were created after it on the
// autorelease pool stack.
//
// CrApplication is responsible for setting handlingSendEvent to true just
// before it sends the event throught the event handling mechanism, and
// returning it to its previous value once the event has been sent.
NSAutoreleasePool* MessagePumpNSApplication::CreateAutoreleasePool() {
NSAutoreleasePool* pool = nil;
DCHECK([NSApp isKindOfClass:[CrApplication class]]);
if (![static_cast<CrApplication*>(NSApp) isHandlingSendEvent]) {
pool = MessagePumpCFRunLoopBase::CreateAutoreleasePool();
}
return pool;
}
// static
MessagePump* MessagePumpMac::Create() {
if ([NSThread isMainThread]) {
return new MessagePumpNSApplication;
}
return new MessagePumpNSRunLoop;
}
} // namespace base