base/synchronization/waitable_event_watcher_win.cc

   1 // Copyright (c) 2011 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.
   4
   5 #include "base/synchronization/waitable_event_watcher.h"
   6
   7 #include "base/compiler_specific.h"
   8 #include "base/synchronization/waitable_event.h"
   9 #include "base/win/object_watcher.h"
  10
  11 namespace base {
  12
  13 WaitableEventWatcher::WaitableEventWatcher()
  14     : event_(NULL) {
  15 }
  16
  17 WaitableEventWatcher::~WaitableEventWatcher() {
  18 }
  19
  20 bool WaitableEventWatcher::StartWatching(
  21     WaitableEvent* event,
  22     const EventCallback& callback) {
  23   callback_ = callback;
  24   event_ = event;
  25   return watcher_.StartWatching(event->handle(), this);
  26 }
  27
  28 void WaitableEventWatcher::StopWatching() {
  29   callback_.Reset();
  30   event_ = NULL;
  31   watcher_.StopWatching();
  32 }
  33
  34 WaitableEvent* WaitableEventWatcher::GetWatchedEvent() {
  35   return event_;
  36 }
  37
  38 void WaitableEventWatcher::OnObjectSignaled(HANDLE h) {
  39   WaitableEvent* event = event_;
  40   EventCallback callback = callback_;
  41   event_ = NULL;
  42   callback_.Reset();
  43   DCHECK(event);
  44
  45   callback.Run(event);
  46 }
  47
  48 }  // namespace base