123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129 |
- // Copyright 2014 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 COMPONENTS_PREFS_SEGREGATED_PREF_STORE_H_
- #define COMPONENTS_PREFS_SEGREGATED_PREF_STORE_H_
- #include <stdint.h>
- #include <memory>
- #include <set>
- #include <string>
- #include "base/callback.h"
- #include "base/compiler_specific.h"
- #include "base/memory/raw_ptr.h"
- #include "base/memory/ref_counted.h"
- #include "base/observer_list.h"
- #include "components/prefs/persistent_pref_store.h"
- #include "components/prefs/prefs_export.h"
- // Provides a unified PersistentPrefStore implementation that splits its storage
- // and retrieval between two underlying PersistentPrefStore instances: a set of
- // preference names is used to partition the preferences.
- //
- // Combines properties of the two stores as follows:
- // * The unified read error will be:
- // Selected Store Error
- // Default Store Error | NO_ERROR | NO_FILE | other selected |
- // NO_ERROR | NO_ERROR | NO_ERROR | other selected |
- // NO_FILE | NO_FILE | NO_FILE | NO_FILE |
- // other default | other default | other default | other default |
- // * The unified initialization success, initialization completion, and
- // read-only state are the boolean OR of the underlying stores' properties.
- class COMPONENTS_PREFS_EXPORT SegregatedPrefStore : public PersistentPrefStore {
- public:
- // Creates an instance that delegates to |selected_pref_store| for the
- // preferences named in |selected_pref_names| and to |default_pref_store|
- // for all others. If an unselected preference is present in
- // |selected_pref_store| (i.e. because it was previously selected) it will
- // be migrated back to |default_pref_store| upon access via a non-const
- // method.
- SegregatedPrefStore(scoped_refptr<PersistentPrefStore> default_pref_store,
- scoped_refptr<PersistentPrefStore> selected_pref_store,
- std::set<std::string> selected_pref_names);
- SegregatedPrefStore(const SegregatedPrefStore&) = delete;
- SegregatedPrefStore& operator=(const SegregatedPrefStore&) = delete;
- // PrefStore implementation
- void AddObserver(Observer* observer) override;
- void RemoveObserver(Observer* observer) override;
- bool HasObservers() const override;
- bool IsInitializationComplete() const override;
- bool GetValue(const std::string& key,
- const base::Value** result) const override;
- base::Value::Dict GetValues() const override;
- // WriteablePrefStore implementation
- void SetValue(const std::string& key,
- std::unique_ptr<base::Value> value,
- uint32_t flags) override;
- void RemoveValue(const std::string& key, uint32_t flags) override;
- void RemoveValuesByPrefixSilently(const std::string& prefix) override;
- // PersistentPrefStore implementation
- bool GetMutableValue(const std::string& key, base::Value** result) override;
- void ReportValueChanged(const std::string& key, uint32_t flags) override;
- void SetValueSilently(const std::string& key,
- std::unique_ptr<base::Value> value,
- uint32_t flags) override;
- bool ReadOnly() const override;
- PrefReadError GetReadError() const override;
- PrefReadError ReadPrefs() override;
- void ReadPrefsAsync(ReadErrorDelegate* error_delegate) override;
- void CommitPendingWrite(
- base::OnceClosure reply_callback = base::OnceClosure(),
- base::OnceClosure synchronous_done_callback =
- base::OnceClosure()) override;
- void SchedulePendingLossyWrites() override;
- void ClearMutableValues() override;
- void OnStoreDeletionFromDisk() override;
- protected:
- ~SegregatedPrefStore() override;
- private:
- // Caches event state from the underlying stores and exposes the state to the
- // provided "outer" SegregatedPrefStore to synthesize external events via
- // |read_error_delegate_| and |observers_|.
- class UnderlyingPrefStoreObserver : public PrefStore::Observer {
- public:
- explicit UnderlyingPrefStoreObserver(SegregatedPrefStore* outer);
- UnderlyingPrefStoreObserver(const UnderlyingPrefStoreObserver&) = delete;
- UnderlyingPrefStoreObserver& operator=(const UnderlyingPrefStoreObserver&) =
- delete;
- // PrefStore::Observer implementation
- void OnPrefValueChanged(const std::string& key) override;
- void OnInitializationCompleted(bool succeeded) override;
- bool initialization_succeeded() const { return initialization_succeeded_; }
- private:
- const raw_ptr<SegregatedPrefStore> outer_;
- bool initialization_succeeded_ = false;
- };
- // Returns true only if all underlying PrefStores have initialized
- // successfully, otherwise false.
- bool IsInitializationSuccessful() const;
- // Returns |selected_pref_store| if |key| is selected and
- // |default_pref_store| otherwise.
- PersistentPrefStore* StoreForKey(const std::string& key);
- const PersistentPrefStore* StoreForKey(const std::string& key) const;
- const scoped_refptr<PersistentPrefStore> default_pref_store_;
- const scoped_refptr<PersistentPrefStore> selected_pref_store_;
- const std::set<std::string> selected_preference_names_;
- std::unique_ptr<PersistentPrefStore::ReadErrorDelegate> read_error_delegate_;
- base::ObserverList<PrefStore::Observer, true>::Unchecked observers_;
- UnderlyingPrefStoreObserver default_observer_;
- UnderlyingPrefStoreObserver selected_observer_;
- };
- #endif // COMPONENTS_PREFS_SEGREGATED_PREF_STORE_H_
|