1// Copyright 2013 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_PREF_HASH_STORE_IMPL_H_
6#define CHROME_BROWSER_PREFS_PREF_HASH_STORE_IMPL_H_
7
8#include <string>
9
10#include "base/compiler_specific.h"
11#include "base/macros.h"
12#include "base/memory/scoped_ptr.h"
13#include "chrome/browser/prefs/pref_hash_calculator.h"
14#include "chrome/browser/prefs/pref_hash_store.h"
15
16class HashStoreContents;
17class PrefHashStoreTransaction;
18
19// Implements PrefHashStoreImpl by storing preference hashes in a
20// HashStoreContents.
21class PrefHashStoreImpl : public PrefHashStore {
22 public:
23  enum StoreVersion {
24    // No hashes have been stored in this PrefHashStore yet.
25    VERSION_UNINITIALIZED = 0,
26    // The hashes in this PrefHashStore were stored before the introduction
27    // of a version number and should be re-initialized.
28    VERSION_PRE_MIGRATION = 1,
29    // The hashes in this PrefHashStore were stored using the latest algorithm.
30    VERSION_LATEST = 2,
31  };
32
33  // Constructs a PrefHashStoreImpl that calculates hashes using
34  // |seed| and |device_id| and stores them in |contents|.
35  //
36  // The same |seed| and |device_id| must be used to load and validate
37  // previously stored hashes in |contents|.
38  PrefHashStoreImpl(const std::string& seed,
39                    const std::string& device_id,
40                    bool use_super_mac);
41
42  virtual ~PrefHashStoreImpl();
43
44  // Provides an external HashStoreContents implementation to be used.
45  // BeginTransaction() will ignore |storage| if this is provided.
46  void set_legacy_hash_store_contents(
47      scoped_ptr<HashStoreContents> legacy_hash_store_contents);
48
49  // Clears the contents of this PrefHashStore. |IsInitialized()| will return
50  // false after this call.
51  void Reset();
52
53  // PrefHashStore implementation.
54  virtual scoped_ptr<PrefHashStoreTransaction> BeginTransaction(
55      scoped_ptr<HashStoreContents> storage) OVERRIDE;
56
57 private:
58  class PrefHashStoreTransactionImpl;
59
60  const PrefHashCalculator pref_hash_calculator_;
61  scoped_ptr<HashStoreContents> legacy_hash_store_contents_;
62  bool use_super_mac_;
63
64  DISALLOW_COPY_AND_ASSIGN(PrefHashStoreImpl);
65};
66
67#endif  // CHROME_BROWSER_PREFS_PREF_HASH_STORE_IMPL_H_
68