Componentize //chrome/browser/prefs/tracked.

chrome/browser/prefs/tracked/hash_store_contents.h

-// 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 CHROME_BROWSER_PREFS_TRACKED_HASH_STORE_CONTENTS_H_
-#define CHROME_BROWSER_PREFS_TRACKED_HASH_STORE_CONTENTS_H_
-
-#include <string>
-
-#include "base/memory/scoped_ptr.h"
-
-namespace base {
-class DictionaryValue;
-} // namespace base
-
-// Provides access to the contents of a preference hash store. The store
-// contains the following data:
-// Contents: a client-defined dictionary that should map preference names to
-// MACs.
-// Version: a client-defined version number for the format of Contents.
-// Super MAC: a MAC that authenticates the entirety of Contents.
-// Legacy hash stores may have an ID that was incorporated into MAC
-// calculations. The ID, if any, is available via |hash_store_id()|.
-class HashStoreContents {
- public:
-  // Used to modify a DictionaryValue stored in the preference hash store. The
-  // MutableDictionary should be destroyed when modifications are complete in
-  // order to allow them to be committed to the underlying storage.
-  class MutableDictionary {
-   public:
-    virtual ~MutableDictionary() {}
-    // Returns the DictionaryValue, which will be created if it does not already
-    // exist.
-    virtual base::DictionaryValue* operator->() = 0;
-  };
-
-  virtual ~HashStoreContents() {}
-
-  // Returns the hash-store ID. May be empty.
-  virtual std::string hash_store_id() const = 0;
-
-  // Discards all data related to this hash store.
-  virtual void Reset() = 0;
-
-  // Indicates whether any data is currently stored for this hash store.
-  virtual bool IsInitialized() const = 0;
-
-  // Retrieves the contents of this hash store. May return NULL if the hash
-  // store has not been initialized.
-  virtual const base::DictionaryValue* GetContents() const = 0;
-
-  // Provides mutable access to the contents of this hash store.
-  virtual scoped_ptr<MutableDictionary> GetMutableContents() = 0;
-
-  // Retrieves the super MAC value previously stored by SetSuperMac. May be
-  // empty if no super MAC has been stored.
-  virtual std::string GetSuperMac() const = 0;
-
-  // Stores a super MAC value for this hash store.
-  virtual void SetSuperMac(const std::string& super_mac) = 0;
-};
-
-#endif  // CHROME_BROWSER_PREFS_TRACKED_HASH_STORE_CONTENTS_H_