| // Copyright 2014 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef SERVICES_PREFERENCES_TRACKED_INTERCEPTABLE_PREF_FILTER_H_ |
| #define SERVICES_PREFERENCES_TRACKED_INTERCEPTABLE_PREF_FILTER_H_ |
| |
| #include <memory> |
| |
| #include "base/callback.h" |
| #include "base/memory/weak_ptr.h" |
| #include "base/values.h" |
| #include "components/prefs/pref_filter.h" |
| |
| // A partial implementation of a PrefFilter whose FilterOnLoad call may be |
| // intercepted by a FilterOnLoadInterceptor. Implementations of |
| // InterceptablePrefFilter are expected to override FinalizeFilterOnLoad rather |
| // than re-overriding FilterOnLoad. |
| class InterceptablePrefFilter |
| : public PrefFilter, |
| public base::SupportsWeakPtr<InterceptablePrefFilter> { |
| public: |
| // A callback to be invoked by a FilterOnLoadInterceptor when its ready to |
| // hand back the |prefs| it was handed for early filtering. |prefs_altered| |
| // indicates whether the |prefs| were actually altered by the |
| // FilterOnLoadInterceptor before being handed back. |
| using FinalizeFilterOnLoadCallback = |
| base::OnceCallback<void(std::unique_ptr<base::DictionaryValue> prefs, |
| bool prefs_altered)>; |
| |
| // A callback to be invoked from FilterOnLoad. It takes ownership of prefs |
| // and may modify them before handing them back to this |
| // InterceptablePrefFilter via |finalize_filter_on_load|. |
| using FilterOnLoadInterceptor = base::OnceCallback<void( |
| FinalizeFilterOnLoadCallback finalize_filter_on_load, |
| std::unique_ptr<base::DictionaryValue> prefs)>; |
| |
| InterceptablePrefFilter(); |
| ~InterceptablePrefFilter() override; |
| |
| // PrefFilter partial implementation. |
| void FilterOnLoad( |
| PostFilterOnLoadCallback post_filter_on_load_callback, |
| std::unique_ptr<base::DictionaryValue> pref_store_contents) override; |
| |
| // Registers |filter_on_load_interceptor| to intercept the next FilterOnLoad |
| // event. At most one FilterOnLoadInterceptor should be registered per |
| // PrefFilter. |
| void InterceptNextFilterOnLoad( |
| FilterOnLoadInterceptor filter_on_load_interceptor); |
| |
| void OnStoreDeletionFromDisk() override; |
| |
| private: |
| // Does any extra filtering required by the implementation of this |
| // InterceptablePrefFilter and hands back the |pref_store_contents| to the |
| // initial caller of FilterOnLoad. |
| virtual void FinalizeFilterOnLoad( |
| PostFilterOnLoadCallback post_filter_on_load_callback, |
| std::unique_ptr<base::DictionaryValue> pref_store_contents, |
| bool prefs_altered) = 0; |
| |
| // Callback to be invoked only once (and subsequently reset) on the next |
| // FilterOnLoad event. It will be allowed to modify the |prefs| handed to |
| // FilterOnLoad before handing them back to this PrefHashFilter. |
| FilterOnLoadInterceptor filter_on_load_interceptor_; |
| }; |
| |
| #endif // SERVICES_PREFERENCES_TRACKED_INTERCEPTABLE_PREF_FILTER_H_ |