components/user_prefs/tracked/tracked_preference_helper.h

   1 // Copyright 2014 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 COMPONENTS_USER_PREFS_TRACKED_TRACKED_PREFERENCE_HELPER_H_
   6 #define COMPONENTS_USER_PREFS_TRACKED_TRACKED_PREFERENCE_HELPER_H_
   7
   8 #include <string>
   9
  10 #include "base/macros.h"
  11 #include "components/user_prefs/tracked/pref_hash_filter.h"
  12 #include "components/user_prefs/tracked/pref_hash_store_transaction.h"
  13
  14 // A TrackedPreferenceHelper is a helper class for TrackedPreference which
  15 // handles decision making and reporting for TrackedPreference's
  16 // implementations.
  17 class TrackedPreferenceHelper {
  18  public:
  19   enum ResetAction {
  20     DONT_RESET,
  21     // WANTED_RESET is reported when DO_RESET would have been reported but the
  22     // current |enforcement_level| doesn't allow a reset for the detected state.
  23     WANTED_RESET,
  24     DO_RESET,
  25   };
  26
  27   TrackedPreferenceHelper(const std::string& pref_path,
  28                           size_t reporting_id,
  29                           size_t reporting_ids_count,
  30                           PrefHashFilter::EnforcementLevel enforcement_level,
  31                           PrefHashFilter::ValueType value_type);
  32
  33   // Returns a ResetAction stating whether a reset is desired (DO_RESET) or not
  34   // (DONT_RESET) based on observing |value_state|. Can also return WANTED_RESET
  35   // if a reset would have been desired but the current |enforcement_level|
  36   // doesn't allow it.
  37   ResetAction GetAction(PrefHashStoreTransaction::ValueState value_state) const;
  38
  39   // Returns true if the preference value may contain personal information.
  40   bool IsPersonal() const;
  41
  42   // Reports |value_state| via UMA under |reporting_id_|.
  43   void ReportValidationResult(
  44       PrefHashStoreTransaction::ValueState value_state) const;
  45
  46   // Reports |reset_action| via UMA under |reporting_id_|.
  47   void ReportAction(ResetAction reset_action) const;
  48
  49   // Reports, via UMA, the |count| of split preference entries that were
  50   // considered invalid in a CHANGED event.
  51   void ReportSplitPreferenceChangedCount(size_t count) const;
  52
  53  private:
  54   const std::string pref_path_;
  55
  56   const size_t reporting_id_;
  57   const size_t reporting_ids_count_;
  58
  59   // Deny setting changes and hash seeding/migration.
  60   const bool enforce_;
  61
  62   const bool personal_;
  63
  64   DISALLOW_COPY_AND_ASSIGN(TrackedPreferenceHelper);
  65 };
  66
  67 #endif  // COMPONENTS_USER_PREFS_TRACKED_TRACKED_PREFERENCE_HELPER_H_