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.
5 #ifndef CHROME_BROWSER_PREFS_TRACKED_INTERCEPTABLE_PREF_FILTER_H_
6 #define CHROME_BROWSER_PREFS_TRACKED_INTERCEPTABLE_PREF_FILTER_H_
8 #include "base/callback.h"
9 #include "base/memory/weak_ptr.h"
10 #include "base/prefs/pref_filter.h"
11 #include "base/values.h"
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.
17 class InterceptablePrefFilter
19 public base::SupportsWeakPtr<InterceptablePrefFilter> {
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;
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;
35 InterceptablePrefFilter();
36 ~InterceptablePrefFilter() override;
38 // PrefFilter partial implementation.
40 const PostFilterOnLoadCallback& post_filter_on_load_callback,
41 scoped_ptr<base::DictionaryValue> pref_store_contents) override;
43 // Registers |filter_on_load_interceptor| to intercept the next FilterOnLoad
44 // event. At most one FilterOnLoadInterceptor should be registered per
46 void InterceptNextFilterOnLoad(
47 const FilterOnLoadInterceptor& filter_on_load_interceptor);
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;
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_;
64 #endif // CHROME_BROWSER_PREFS_TRACKED_INTERCEPTABLE_PREF_FILTER_H_