1 // Copyright 2013 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 #ifndef COMPONENTS_POLICY_CORE_COMMON_ASYNC_POLICY_PROVIDER_H_ 6 #define COMPONENTS_POLICY_CORE_COMMON_ASYNC_POLICY_PROVIDER_H_ 7 8 #include "base/cancelable_callback.h" 9 #include "base/memory/ref_counted.h" 10 #include "base/memory/scoped_ptr.h" 11 #include "base/memory/weak_ptr.h" 12 #include "base/threading/non_thread_safe.h" 13 #include "components/policy/core/common/configuration_policy_provider.h" 14 #include "components/policy/policy_export.h" 15 16 namespace base { 17 class MessageLoopProxy; 18 } 19 20 namespace policy { 21 22 class AsyncPolicyLoader; 23 class PolicyBundle; 24 class SchemaRegistry; 25 26 // A policy provider that loads its policies asynchronously on a background 27 // thread. Platform-specific providers are created by passing an implementation 28 // of AsyncPolicyLoader to a new AsyncPolicyProvider. 29 class POLICY_EXPORT AsyncPolicyProvider : public ConfigurationPolicyProvider, 30 public base::NonThreadSafe { 31 public: 32 // The AsyncPolicyProvider does a synchronous load in its constructor, and 33 // therefore it needs the |registry| at construction time. The same |registry| 34 // should be passed later to Init(). 35 AsyncPolicyProvider(SchemaRegistry* registry, 36 scoped_ptr<AsyncPolicyLoader> loader); 37 virtual ~AsyncPolicyProvider(); 38 39 // ConfigurationPolicyProvider implementation. 40 virtual void Init(SchemaRegistry* registry) OVERRIDE; 41 virtual void Shutdown() OVERRIDE; 42 virtual void RefreshPolicies() OVERRIDE; 43 44 private: 45 // Helper for RefreshPolicies(). 46 void ReloadAfterRefreshSync(); 47 48 // Invoked with the latest bundle loaded by the |loader_|. 49 void OnLoaderReloaded(scoped_ptr<PolicyBundle> bundle); 50 51 // Callback passed to the loader that it uses to pass back the current policy 52 // bundle to the provider. This is invoked on the background thread and 53 // forwards to OnLoaderReloaded() on the loop that owns the provider, 54 // if |weak_this| is still valid. 55 static void LoaderUpdateCallback(scoped_refptr<base::MessageLoopProxy> loop, 56 base::WeakPtr<AsyncPolicyProvider> weak_this, 57 scoped_ptr<PolicyBundle> bundle); 58 59 // The |loader_| that does the platform-specific policy loading. It lives 60 // on the background thread but is owned by |this|. 61 AsyncPolicyLoader* loader_; 62 63 // Used to get a WeakPtr to |this| for the update callback given to the 64 // loader. 65 base::WeakPtrFactory<AsyncPolicyProvider> weak_factory_; 66 67 // Callback used to synchronize RefreshPolicies() calls with the background 68 // thread. See the implementation for the details. 69 base::CancelableClosure refresh_callback_; 70 71 DISALLOW_COPY_AND_ASSIGN(AsyncPolicyProvider); 72 }; 73 74 } // namespace policy 75 76 #endif // COMPONENTS_POLICY_CORE_COMMON_ASYNC_POLICY_PROVIDER_H_ 77