DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (4b332005f925)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
// Copyright (c) 2009 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_loop.h"

#include <algorithm>

#include "mozilla/Atomics.h"
#include "base/compiler_specific.h"
#include "base/logging.h"
#include "base/message_pump_default.h"
#include "base/string_util.h"
#include "base/thread_local.h"

#if defined(OS_MACOSX)
#  include "base/message_pump_mac.h"
#endif
#if defined(OS_POSIX)
#  include "base/message_pump_libevent.h"
#endif
#if defined(OS_LINUX) || defined(OS_BSD)
#  if defined(MOZ_WIDGET_GTK)
#    include "base/message_pump_glib.h"
#  endif
#endif
#ifdef ANDROID
#  include "base/message_pump_android.h"
#endif
#include "nsISerialEventTarget.h"
#ifdef MOZ_TASK_TRACER
#  include "GeckoTaskTracer.h"
#  include "TracedTaskCommon.h"
#endif

#include "MessagePump.h"

using base::Time;
using base::TimeDelta;
using base::TimeTicks;

using mozilla::Runnable;

static base::ThreadLocalPointer<MessageLoop>& get_tls_ptr() {
  static base::ThreadLocalPointer<MessageLoop> tls_ptr;
  return tls_ptr;
}

//------------------------------------------------------------------------------

// Logical events for Histogram profiling. Run with -message-loop-histogrammer
// to get an accounting of messages and actions taken on each thread.
static const int kTaskRunEvent = 0x1;
static const int kTimerEvent = 0x2;

// Provide range of message IDs for use in histogramming and debug display.
static const int kLeastNonZeroMessageId = 1;
static const int kMaxMessageId = 1099;
static const int kNumberOfDistinctMessagesDisplayed = 1100;

//------------------------------------------------------------------------------

#if defined(OS_WIN)

// Upon a SEH exception in this thread, it restores the original unhandled
// exception filter.
static int SEHFilter(LPTOP_LEVEL_EXCEPTION_FILTER old_filter) {
  ::SetUnhandledExceptionFilter(old_filter);
  return EXCEPTION_CONTINUE_SEARCH;
}

// Retrieves a pointer to the current unhandled exception filter. There
// is no standalone getter method.
static LPTOP_LEVEL_EXCEPTION_FILTER GetTopSEHFilter() {
  LPTOP_LEVEL_EXCEPTION_FILTER top_filter = NULL;
  top_filter = ::SetUnhandledExceptionFilter(0);
  ::SetUnhandledExceptionFilter(top_filter);
  return top_filter;
}

#endif  // defined(OS_WIN)

//------------------------------------------------------------------------------

class MessageLoop::EventTarget : public nsISerialEventTarget,
                                 public MessageLoop::DestructionObserver {
 public:
  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_NSIEVENTTARGET_FULL

  explicit EventTarget(MessageLoop* aLoop) : mLoop(aLoop) {
    aLoop->AddDestructionObserver(this);
  }

 private:
  virtual ~EventTarget() {
    if (mLoop) {
      mLoop->RemoveDestructionObserver(this);
    }
  }

  void WillDestroyCurrentMessageLoop() override {
    mLoop->RemoveDestructionObserver(this);
    mLoop = nullptr;
  }

  MessageLoop* mLoop;
};

NS_IMPL_ISUPPORTS(MessageLoop::EventTarget, nsIEventTarget,
                  nsISerialEventTarget)

NS_IMETHODIMP_(bool)
MessageLoop::EventTarget::IsOnCurrentThreadInfallible() {
  return mLoop == MessageLoop::current();
}

NS_IMETHODIMP
MessageLoop::EventTarget::IsOnCurrentThread(bool* aResult) {
  *aResult = IsOnCurrentThreadInfallible();
  return NS_OK;
}

NS_IMETHODIMP
MessageLoop::EventTarget::DispatchFromScript(nsIRunnable* aEvent,
                                             uint32_t aFlags) {
  nsCOMPtr<nsIRunnable> event(aEvent);
  return Dispatch(event.forget(), aFlags);
}

NS_IMETHODIMP
MessageLoop::EventTarget::Dispatch(already_AddRefed<nsIRunnable> aEvent,
                                   uint32_t aFlags) {
  if (!mLoop) {
    return NS_ERROR_NOT_INITIALIZED;
  }

  if (aFlags != NS_DISPATCH_NORMAL) {
    return NS_ERROR_NOT_IMPLEMENTED;
  }

  mLoop->PostTask(std::move(aEvent));
  return NS_OK;
}

NS_IMETHODIMP
MessageLoop::EventTarget::DelayedDispatch(already_AddRefed<nsIRunnable> aEvent,
                                          uint32_t aDelayMs) {
  if (!mLoop) {
    return NS_ERROR_NOT_INITIALIZED;
  }

  mLoop->PostDelayedTask(std::move(aEvent), aDelayMs);
  return NS_OK;
}

//------------------------------------------------------------------------------

// static
MessageLoop* MessageLoop::current() { return get_tls_ptr().Get(); }

// static
void MessageLoop::set_current(MessageLoop* loop) { get_tls_ptr().Set(loop); }

static mozilla::Atomic<int32_t> message_loop_id_seq(0);

MessageLoop::MessageLoop(Type type, nsIEventTarget* aEventTarget)
    : type_(type),
      id_(++message_loop_id_seq),
      nestable_tasks_allowed_(true),
      exception_restoration_(false),
      incoming_queue_lock_("MessageLoop Incoming Queue Lock"),
      state_(NULL),
      run_depth_base_(1),
      shutting_down_(false),
#ifdef OS_WIN
      os_modal_loop_(false),
#endif  // OS_WIN
      transient_hang_timeout_(0),
      permanent_hang_timeout_(0),
      next_sequence_num_(0) {
  DCHECK(!current()) << "should only have one message loop per thread";
  get_tls_ptr().Set(this);

  // Must initialize after current() is initialized.
  mEventTarget = new EventTarget(this);

  switch (type_) {
    case TYPE_MOZILLA_PARENT:
      MOZ_RELEASE_ASSERT(!aEventTarget);
      pump_ = new mozilla::ipc::MessagePump(aEventTarget);
      return;
    case TYPE_MOZILLA_CHILD:
      MOZ_RELEASE_ASSERT(!aEventTarget);
      pump_ = new mozilla::ipc::MessagePumpForChildProcess();
      // There is a MessageLoop Run call from XRE_InitChildProcess
      // and another one from MessagePumpForChildProcess. The one
      // from MessagePumpForChildProcess becomes the base, so we need
      // to set run_depth_base_ to 2 or we'll never be able to process
      // Idle tasks.
      run_depth_base_ = 2;
      return;
    case TYPE_MOZILLA_NONMAINTHREAD:
      pump_ = new mozilla::ipc::MessagePumpForNonMainThreads(aEventTarget);
      return;
#if defined(OS_WIN)
    case TYPE_MOZILLA_NONMAINUITHREAD:
      pump_ = new mozilla::ipc::MessagePumpForNonMainUIThreads(aEventTarget);
      return;
#endif
#if defined(MOZ_WIDGET_ANDROID)
    case TYPE_MOZILLA_ANDROID_UI:
      MOZ_RELEASE_ASSERT(aEventTarget);
      pump_ = new mozilla::ipc::MessagePumpForAndroidUI(aEventTarget);
      return;
#endif  // defined(MOZ_WIDGET_ANDROID)
    default:
      // Create one of Chromium's standard MessageLoop types below.
      break;
  }

#if defined(OS_WIN)
  // TODO(rvargas): Get rid of the OS guards.
  if (type_ == TYPE_DEFAULT) {
    pump_ = new base::MessagePumpDefault();
  } else if (type_ == TYPE_IO) {
    pump_ = new base::MessagePumpForIO();
  } else {
    DCHECK(type_ == TYPE_UI);
    pump_ = new base::MessagePumpForUI();
  }
#elif defined(OS_POSIX)
  if (type_ == TYPE_UI) {
#  if defined(OS_MACOSX)
    pump_ = base::MessagePumpMac::Create();
#  elif defined(OS_LINUX) || defined(OS_BSD)
    pump_ = new base::MessagePumpForUI();
#  endif  // OS_LINUX
  } else if (type_ == TYPE_IO) {
    pump_ = new base::MessagePumpLibevent();
  } else {
    pump_ = new base::MessagePumpDefault();
  }
#endif    // OS_POSIX
}

MessageLoop::~MessageLoop() {
  DCHECK(this == current());

  // Let interested parties have one last shot at accessing this.
  FOR_EACH_OBSERVER(DestructionObserver, destruction_observers_,
                    WillDestroyCurrentMessageLoop());

  DCHECK(!state_);

  // Clean up any unprocessed tasks, but take care: deleting a task could
  // result in the addition of more tasks (e.g., via DeleteSoon).  We set a
  // limit on the number of times we will allow a deleted task to generate more
  // tasks.  Normally, we should only pass through this loop once or twice.  If
  // we end up hitting the loop limit, then it is probably due to one task that
  // is being stubborn.  Inspect the queues to see who is left.
  bool did_work;
  for (int i = 0; i < 100; ++i) {
    DeletePendingTasks();
    ReloadWorkQueue();
    // If we end up with empty queues, then break out of the loop.
    did_work = DeletePendingTasks();
    if (!did_work) break;
  }
  DCHECK(!did_work);

  // OK, now make it so that no one can find us.
  get_tls_ptr().Set(NULL);
}

void MessageLoop::AddDestructionObserver(DestructionObserver* obs) {
  DCHECK(this == current());
  destruction_observers_.AddObserver(obs);
}

void MessageLoop::RemoveDestructionObserver(DestructionObserver* obs) {
  DCHECK(this == current());
  destruction_observers_.RemoveObserver(obs);
}

void MessageLoop::Run() {
  AutoRunState save_state(this);
  RunHandler();
}

// Runs the loop in two different SEH modes:
// enable_SEH_restoration_ = false : any unhandled exception goes to the last
// one that calls SetUnhandledExceptionFilter().
// enable_SEH_restoration_ = true : any unhandled exception goes to the filter
// that was existed before the loop was run.
void MessageLoop::RunHandler() {
#if defined(OS_WIN)
  if (exception_restoration_) {
    LPTOP_LEVEL_EXCEPTION_FILTER current_filter = GetTopSEHFilter();
    MOZ_SEH_TRY { RunInternal(); }
    MOZ_SEH_EXCEPT(SEHFilter(current_filter)) {}
    return;
  }
#endif

  RunInternal();
}

//------------------------------------------------------------------------------

void MessageLoop::RunInternal() {
  DCHECK(this == current());
  pump_->Run(this);
}

//------------------------------------------------------------------------------
// Wrapper functions for use in above message loop framework.

bool MessageLoop::ProcessNextDelayedNonNestableTask() {
  if (state_->run_depth > run_depth_base_) return false;

  if (deferred_non_nestable_work_queue_.empty()) return false;

  nsCOMPtr<nsIRunnable> task =
      deferred_non_nestable_work_queue_.front().task.forget();
  deferred_non_nestable_work_queue_.pop();

  RunTask(task.forget());
  return true;
}

//------------------------------------------------------------------------------

void MessageLoop::Quit() {
  DCHECK(current() == this);
  if (state_) {
    state_->quit_received = true;
  } else {
    NOTREACHED() << "Must be inside Run to call Quit";
  }
}

void MessageLoop::PostTask(already_AddRefed<nsIRunnable> task) {
  PostTask_Helper(std::move(task), 0);
}

void MessageLoop::PostDelayedTask(already_AddRefed<nsIRunnable> task,
                                  int delay_ms) {
  PostTask_Helper(std::move(task), delay_ms);
}

void MessageLoop::PostIdleTask(already_AddRefed<nsIRunnable> task) {
  DCHECK(current() == this);
  MOZ_ASSERT(NS_IsMainThread());

  PendingTask pending_task(std::move(task), false);
  deferred_non_nestable_work_queue_.push(std::move(pending_task));
}

// Possibly called on a background thread!
void MessageLoop::PostTask_Helper(already_AddRefed<nsIRunnable> task,
                                  int delay_ms) {
  if (nsIEventTarget* target = pump_->GetXPCOMThread()) {
    nsresult rv;
    if (delay_ms) {
      rv = target->DelayedDispatch(std::move(task), delay_ms);
    } else {
      rv = target->Dispatch(std::move(task), 0);
    }
    MOZ_ALWAYS_SUCCEEDS(rv);
    return;
  }

  // Tasks should only be queued before or during the Run loop, not after.
  MOZ_ASSERT(!shutting_down_);

#ifdef MOZ_TASK_TRACER
  nsCOMPtr<nsIRunnable> tracedTask = task;
  if (mozilla::tasktracer::IsStartLogging()) {
    tracedTask = mozilla::tasktracer::CreateTracedRunnable(tracedTask.forget());
    (static_cast<mozilla::tasktracer::TracedRunnable*>(tracedTask.get()))
        ->DispatchTask();
  }
  PendingTask pending_task(tracedTask.forget(), true);
#else
  PendingTask pending_task(std::move(task), true);
#endif

  if (delay_ms > 0) {
    pending_task.delayed_run_time =
        TimeTicks::Now() + TimeDelta::FromMilliseconds(delay_ms);
  } else {
    DCHECK(delay_ms == 0) << "delay should not be negative";
  }

  // Warning: Don't try to short-circuit, and handle this thread's tasks more
  // directly, as it could starve handling of foreign threads.  Put every task
  // into this queue.

  RefPtr<base::MessagePump> pump;
  {
    mozilla::MutexAutoLock locked(incoming_queue_lock_);
    incoming_queue_.push(std::move(pending_task));
    pump = pump_;
  }
  // Since the incoming_queue_ may contain a task that destroys this message
  // loop, we cannot exit incoming_queue_lock_ until we are done with |this|.
  // We use a stack-based reference to the message pump so that we can call
  // ScheduleWork outside of incoming_queue_lock_.

  pump->ScheduleWork();
}

void MessageLoop::SetNestableTasksAllowed(bool allowed) {
  if (nestable_tasks_allowed_ != allowed) {
    nestable_tasks_allowed_ = allowed;
    if (!nestable_tasks_allowed_) return;
    // Start the native pump if we are not already pumping.
    pump_->ScheduleWorkForNestedLoop();
  }
}

void MessageLoop::ScheduleWork() {
  // Start the native pump if we are not already pumping.
  pump_->ScheduleWork();
}

bool MessageLoop::NestableTasksAllowed() const {
  return nestable_tasks_allowed_;
}

//------------------------------------------------------------------------------

void MessageLoop::RunTask(already_AddRefed<nsIRunnable> aTask) {
  DCHECK(nestable_tasks_allowed_);
  // Execute the task and assume the worst: It is probably not reentrant.
  nestable_tasks_allowed_ = false;

  nsCOMPtr<nsIRunnable> task = aTask;
  task->Run();
  task = nullptr;

  nestable_tasks_allowed_ = true;
}

bool MessageLoop::DeferOrRunPendingTask(PendingTask&& pending_task) {
  if (pending_task.nestable || state_->run_depth <= run_depth_base_) {
    RunTask(pending_task.task.forget());
    // Show that we ran a task (Note: a new one might arrive as a
    // consequence!).
    return true;
  }

  // We couldn't run the task now because we're in a nested message loop
  // and the task isn't nestable.
  deferred_non_nestable_work_queue_.push(std::move(pending_task));
  return false;
}

void MessageLoop::AddToDelayedWorkQueue(const PendingTask& pending_task) {
  // Move to the delayed work queue.  Initialize the sequence number
  // before inserting into the delayed_work_queue_.  The sequence number
  // is used to faciliate FIFO sorting when two tasks have the same
  // delayed_run_time value.
  PendingTask new_pending_task(pending_task);
  new_pending_task.sequence_num = next_sequence_num_++;
  delayed_work_queue_.push(std::move(new_pending_task));
}

void MessageLoop::ReloadWorkQueue() {
  // We can improve performance of our loading tasks from incoming_queue_ to
  // work_queue_ by waiting until the last minute (work_queue_ is empty) to
  // load.  That reduces the number of locks-per-task significantly when our
  // queues get large.
  if (!work_queue_.empty())
    return;  // Wait till we *really* need to lock and load.

  // Acquire all we can from the inter-thread queue with one lock acquisition.
  {
    mozilla::MutexAutoLock lock(incoming_queue_lock_);
    if (incoming_queue_.empty()) return;
    std::swap(incoming_queue_, work_queue_);
    DCHECK(incoming_queue_.empty());
  }
}

bool MessageLoop::DeletePendingTasks() {
  MOZ_ASSERT(work_queue_.empty());
  bool did_work = !deferred_non_nestable_work_queue_.empty();
  while (!deferred_non_nestable_work_queue_.empty()) {
    deferred_non_nestable_work_queue_.pop();
  }
  did_work |= !delayed_work_queue_.empty();
  while (!delayed_work_queue_.empty()) {
    delayed_work_queue_.pop();
  }
  return did_work;
}

bool MessageLoop::DoWork() {
  if (!nestable_tasks_allowed_) {
    // Task can't be executed right now.
    return false;
  }

  for (;;) {
    ReloadWorkQueue();
    if (work_queue_.empty()) break;

    // Execute oldest task.
    do {
      PendingTask pending_task = std::move(work_queue_.front());
      work_queue_.pop();
      if (!pending_task.delayed_run_time.is_null()) {
        // NB: Don't move, because we use this later!
        AddToDelayedWorkQueue(pending_task);
        // If we changed the topmost task, then it is time to re-schedule.
        if (delayed_work_queue_.top().task == pending_task.task)
          pump_->ScheduleDelayedWork(pending_task.delayed_run_time);
      } else {
        if (DeferOrRunPendingTask(std::move(pending_task))) return true;
      }
    } while (!work_queue_.empty());
  }

  // Nothing happened.
  return false;
}

bool MessageLoop::DoDelayedWork(TimeTicks* next_delayed_work_time) {
  if (!nestable_tasks_allowed_ || delayed_work_queue_.empty()) {
    *next_delayed_work_time = TimeTicks();
    return false;
  }

  if (delayed_work_queue_.top().delayed_run_time > TimeTicks::Now()) {
    *next_delayed_work_time = delayed_work_queue_.top().delayed_run_time;
    return false;
  }

  PendingTask pending_task = delayed_work_queue_.top();
  delayed_work_queue_.pop();

  if (!delayed_work_queue_.empty())
    *next_delayed_work_time = delayed_work_queue_.top().delayed_run_time;

  return DeferOrRunPendingTask(std::move(pending_task));
}

bool MessageLoop::DoIdleWork() {
  if (ProcessNextDelayedNonNestableTask()) return true;

  if (state_->quit_received) pump_->Quit();

  return false;
}

//------------------------------------------------------------------------------
// MessageLoop::AutoRunState

MessageLoop::AutoRunState::AutoRunState(MessageLoop* loop) : loop_(loop) {
  // Top-level Run should only get called once.
  MOZ_ASSERT(!loop_->shutting_down_);

  // Make the loop reference us.
  previous_state_ = loop_->state_;
  if (previous_state_) {
    run_depth = previous_state_->run_depth + 1;
  } else {
    run_depth = 1;
  }
  loop_->state_ = this;

  // Initialize the other fields:
  quit_received = false;
#if defined(OS_WIN)
  dispatcher = NULL;
#endif
}

MessageLoop::AutoRunState::~AutoRunState() {
  loop_->state_ = previous_state_;

  // If exiting a top-level Run, then we're shutting down.
  loop_->shutting_down_ = !previous_state_;
}

//------------------------------------------------------------------------------
// MessageLoop::PendingTask

bool MessageLoop::PendingTask::operator<(const PendingTask& other) const {
  // Since the top of a priority queue is defined as the "greatest" element, we
  // need to invert the comparison here.  We want the smaller time to be at the
  // top of the heap.

  if (delayed_run_time < other.delayed_run_time) return false;

  if (delayed_run_time > other.delayed_run_time) return true;

  // If the times happen to match, then we use the sequence number to decide.
  // Compare the difference to support integer roll-over.
  return (sequence_num - other.sequence_num) > 0;
}

//------------------------------------------------------------------------------
// MessageLoop::SerialEventTarget

nsISerialEventTarget* MessageLoop::SerialEventTarget() { return mEventTarget; }

//------------------------------------------------------------------------------
// MessageLoopForUI

#if defined(OS_WIN)

void MessageLoopForUI::Run(Dispatcher* dispatcher) {
  AutoRunState save_state(this);
  state_->dispatcher = dispatcher;
  RunHandler();
}

void MessageLoopForUI::AddObserver(Observer* observer) {
  pump_win()->AddObserver(observer);
}

void MessageLoopForUI::RemoveObserver(Observer* observer) {
  pump_win()->RemoveObserver(observer);
}

void MessageLoopForUI::WillProcessMessage(const MSG& message) {
  pump_win()->WillProcessMessage(message);
}
void MessageLoopForUI::DidProcessMessage(const MSG& message) {
  pump_win()->DidProcessMessage(message);
}
void MessageLoopForUI::PumpOutPendingPaintMessages() {
  pump_ui()->PumpOutPendingPaintMessages();
}

#endif  // defined(OS_WIN)

//------------------------------------------------------------------------------
// MessageLoopForIO

#if defined(OS_WIN)

void MessageLoopForIO::RegisterIOHandler(HANDLE file, IOHandler* handler) {
  pump_io()->RegisterIOHandler(file, handler);
}

bool MessageLoopForIO::WaitForIOCompletion(DWORD timeout, IOHandler* filter) {
  return pump_io()->WaitForIOCompletion(timeout, filter);
}

#elif defined(OS_POSIX)

bool MessageLoopForIO::WatchFileDescriptor(int fd, bool persistent, Mode mode,
                                           FileDescriptorWatcher* controller,
                                           Watcher* delegate) {
  return pump_libevent()->WatchFileDescriptor(
      fd, persistent, static_cast<base::MessagePumpLibevent::Mode>(mode),
      controller, delegate);
}

bool MessageLoopForIO::CatchSignal(int sig, SignalEvent* sigevent,
                                   SignalWatcher* delegate) {
  return pump_libevent()->CatchSignal(sig, sigevent, delegate);
}

#endif