Implement the windows policy provider based on the AsyncPolicyLoader.

chrome/browser/policy/policy_loader_win.h

+// Copyright (c) 2012 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.
+
+#ifndef CHROME_BROWSER_POLICY_POLICY_LOADER_WIN_H_
+#define CHROME_BROWSER_POLICY_POLICY_LOADER_WIN_H_
+#pragma once
+
+#include "base/synchronization/waitable_event.h"
+#include "base/win/object_watcher.h"
+#include "chrome/browser/policy/async_policy_loader.h"
+
+namespace policy {
+
+struct PolicyDefinitionList;
+
+// Loads policies from the Windows registry, and watches for Group Policy
+// notifications to trigger reloads.
+class PolicyLoaderWin : public AsyncPolicyLoader,
+                        public base::win::ObjectWatcher::Delegate {
+ public:
+  explicit PolicyLoaderWin(const PolicyDefinitionList* policy_list);
+  virtual ~PolicyLoaderWin();
+
+  // AsyncPolicyLoader implementation.
+  virtual void InitOnFile() OVERRIDE;
+  virtual scoped_ptr<PolicyBundle> Load() OVERRIDE;
+
+ private:
+  // Installs the watchers for the Group Policy update events.
+  void SetupWatches();
+
+  // ObjectWatcher::Delegate overrides:
+  virtual void OnObjectSignaled(HANDLE object) OVERRIDE;
+
+  bool is_initialized_;
+  const PolicyDefinitionList* policy_list_;
+
+  base::WaitableEvent user_policy_changed_event_;
+  base::WaitableEvent machine_policy_changed_event_;
+  base::win::ObjectWatcher user_policy_watcher_;
+  base::win::ObjectWatcher machine_policy_watcher_;
+  bool user_policy_watcher_failed_;
+  bool machine_policy_watcher_failed_;
+
+  DISALLOW_COPY_AND_ASSIGN(PolicyLoaderWin);
+};
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_POLICY_POLICY_LOADER_WIN_H_