1// Copyright 2014 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 CHROME_BROWSER_PREFS_INTERCEPTABLE_PREF_FILTER_H_ 6#define CHROME_BROWSER_PREFS_INTERCEPTABLE_PREF_FILTER_H_ 7 8#include "base/callback.h" 9#include "base/memory/weak_ptr.h" 10#include "base/prefs/pref_filter.h" 11#include "base/values.h" 12 13// A partial implementation of a PrefFilter whose FilterOnLoad call may be 14// intercepted by a FilterOnLoadInterceptor. Implementations of 15// InterceptablePrefFilter are expected to override FinalizeFilterOnLoad rather 16// than re-overriding FilterOnLoad. 17class InterceptablePrefFilter 18 : public PrefFilter, 19 public base::SupportsWeakPtr<InterceptablePrefFilter> { 20 public: 21 // A callback to be invoked by a FilterOnLoadInterceptor when its ready to 22 // hand back the |prefs| it was handed for early filtering. |prefs_altered| 23 // indicates whether the |prefs| were actually altered by the 24 // FilterOnLoadInterceptor before being handed back. 25 typedef base::Callback<void(scoped_ptr<base::DictionaryValue> prefs, 26 bool prefs_altered)> FinalizeFilterOnLoadCallback; 27 28 // A callback to be invoked from FilterOnLoad. It takes ownership of prefs 29 // and may modify them before handing them back to this 30 // InterceptablePrefFilter via |finalize_filter_on_load|. 31 typedef base::Callback< 32 void(const FinalizeFilterOnLoadCallback& finalize_filter_on_load, 33 scoped_ptr<base::DictionaryValue> prefs)> FilterOnLoadInterceptor; 34 35 InterceptablePrefFilter(); 36 virtual ~InterceptablePrefFilter(); 37 38 // PrefFilter partial implementation. 39 virtual void FilterOnLoad( 40 const PostFilterOnLoadCallback& post_filter_on_load_callback, 41 scoped_ptr<base::DictionaryValue> pref_store_contents) OVERRIDE; 42 43 // Registers |filter_on_load_interceptor| to intercept the next FilterOnLoad 44 // event. At most one FilterOnLoadInterceptor should be registered per 45 // PrefFilter. 46 void InterceptNextFilterOnLoad( 47 const FilterOnLoadInterceptor& filter_on_load_interceptor); 48 49 private: 50 // Does any extra filtering required by the implementation of this 51 // InterceptablePrefFilter and hands back the |pref_store_contents| to the 52 // initial caller of FilterOnLoad. 53 virtual void FinalizeFilterOnLoad( 54 const PostFilterOnLoadCallback& post_filter_on_load_callback, 55 scoped_ptr<base::DictionaryValue> pref_store_contents, 56 bool prefs_altered) = 0; 57 58 // Callback to be invoked only once (and subsequently reset) on the next 59 // FilterOnLoad event. It will be allowed to modify the |prefs| handed to 60 // FilterOnLoad before handing them back to this PrefHashFilter. 61 FilterOnLoadInterceptor filter_on_load_interceptor_; 62}; 63 64#endif // CHROME_BROWSER_PREFS_INTERCEPTABLE_PREF_FILTER_H_ 65