chrome/browser/safe_browsing/incident_reporting/state_store.h

   1 // Copyright 2015 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_SAFE_BROWSING_INCIDENT_REPORTING_STATE_STORE_H_
   6 #define CHROME_BROWSER_SAFE_BROWSING_INCIDENT_REPORTING_STATE_STORE_H_
   7
   8 #include <string>
   9
  10 #include "base/logging.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/prefs/scoped_user_pref_update.h"
  13
  14 class Profile;
  15
  16 namespace safe_browsing {
  17
  18 enum class IncidentType : int32_t;
  19
  20 // The storage to track which incidents have been reported for a profile. Only
  21 // usable on the UI thread.
  22 class StateStore {
  23  public:
  24   using IncidentDigest = uint32_t;
  25
  26   // An object through which modifications to a StateStore can be made. Changes
  27   // are visible to the StateStore immediately and are written to persistent
  28   // storage when the instance is destroyed (or shortly thereafter). Only one
  29   // transaction may be live for a given StateStore at a given time. Instances
  30   // are typically created on the stack for immediate use.
  31   class Transaction {
  32    public:
  33     explicit Transaction(StateStore* store);
  34     ~Transaction();
  35
  36     // Marks the described incident as having been reported.
  37     void MarkAsReported(IncidentType type,
  38                         const std::string& key,
  39                         IncidentDigest digest);
  40
  41     // Clears all data associated with an incident type.
  42     void ClearForType(IncidentType type);
  43
  44     // Clears all data in the store.
  45     void ClearAll();
  46
  47    private:
  48     friend class StateStore;
  49
  50     // Returns a writable view on the incidents_sent preference. The act of
  51     // obtaining this view will cause a serialize-and-write operation to be
  52     // scheduled when the transaction terminates. Use the store's
  53     // |incidents_sent_| member directly to simply query the preference.
  54     base::DictionaryValue* GetPrefDict();
  55
  56     // Replaces the contents of the underlying dictionary value.
  57     void ReplacePrefDict(scoped_ptr<base::DictionaryValue> pref_dict);
  58
  59     // The store corresponding to this transaction.
  60     StateStore* store_;
  61
  62     // A ScopedUserPrefUpdate through which changes to the incidents_sent
  63     // preference are made.
  64     scoped_ptr<DictionaryPrefUpdate> pref_update_;
  65
  66     DISALLOW_COPY_AND_ASSIGN(Transaction);
  67   };
  68
  69   explicit StateStore(Profile* profile);
  70   ~StateStore();
  71
  72   // Returns true if the described incident has already been reported.
  73   bool HasBeenReported(IncidentType type,
  74                        const std::string& key,
  75                        IncidentDigest digest);
  76
  77  private:
  78   // Called on load to clear values that are no longer used.
  79   void CleanLegacyValues(Transaction* transaction);
  80
  81   // The profile to which this state corresponds.
  82   Profile* profile_;
  83
  84   // A read-only view on the profile's incidents_sent preference.
  85   const base::DictionaryValue* incidents_sent_;
  86
  87 #if DCHECK_IS_ON()
  88   // True when a Transaction instance is outstanding.
  89   bool has_transaction_;
  90 #endif
  91
  92   DISALLOW_COPY_AND_ASSIGN(StateStore);
  93 };
  94
  95 }  // namespace safe_browsing
  96
  97 #endif  // CHROME_BROWSER_SAFE_BROWSING_INCIDENT_REPORTING_STATE_STORE_H_