1 files changed, 735 insertions, 0 deletions
diff --git a/ipc/chromium/src/base/message_pump_mac.mm b/ipc/chromium/src/base/message_pump_mac.mm
new file mode 100644
index 0000000000..1382e2a0dc
--- /dev/null
+++ b/ipc/chromium/src/base/message_pump_mac.mm
@@ -0,0 +1,735 @@
+// 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 TimeTicks& delayed_work_time) {
+  TimeDelta delta = delayed_work_time - TimeTicks::Now();
+  delayed_work_fire_time_ = CFAbsoluteTimeGetCurrent() + delta.InSecondsF();
+  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);
+
+  TimeTicks next_time;
+  delegate_->DoDelayedWork(&next_time);
+
+  bool more_work = !next_time.is_null();
+  if (more_work) {
+    TimeDelta delay = next_time - TimeTicks::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:NSEventMaskAny
+                                          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:NSEventTypeApplicationDefined
+                                      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