chrome/browser/prefs/tracked/segregated_pref_store.cc

   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 #include "chrome/browser/prefs/tracked/segregated_pref_store.h"
   6
   7 #include "base/logging.h"
   8 #include "base/stl_util.h"
   9 #include "base/values.h"
  10
  11 SegregatedPrefStore::AggregatingObserver::AggregatingObserver(
  12     SegregatedPrefStore* outer)
  13     : outer_(outer),
  14       failed_sub_initializations_(0),
  15       successful_sub_initializations_(0) {}
  16
  17 void SegregatedPrefStore::AggregatingObserver::OnPrefValueChanged(
  18     const std::string& key) {
  19   // There is no need to tell clients about changes if they have not yet been
  20   // told about initialization.
  21   if (failed_sub_initializations_ + successful_sub_initializations_ < 2)
  22     return;
  23
  24   FOR_EACH_OBSERVER(
  25       PrefStore::Observer, outer_->observers_, OnPrefValueChanged(key));
  26 }
  27
  28 void SegregatedPrefStore::AggregatingObserver::OnInitializationCompleted(
  29     bool succeeded) {
  30   if (succeeded)
  31     ++successful_sub_initializations_;
  32   else
  33     ++failed_sub_initializations_;
  34
  35   DCHECK_LE(failed_sub_initializations_ + successful_sub_initializations_, 2);
  36
  37   if (failed_sub_initializations_ + successful_sub_initializations_ == 2) {
  38     if (successful_sub_initializations_ == 2 && outer_->read_error_delegate_) {
  39       PersistentPrefStore::PrefReadError read_error = outer_->GetReadError();
  40       if (read_error != PersistentPrefStore::PREF_READ_ERROR_NONE)
  41         outer_->read_error_delegate_->OnError(read_error);
  42     }
  43
  44     FOR_EACH_OBSERVER(
  45         PrefStore::Observer,
  46         outer_->observers_,
  47         OnInitializationCompleted(successful_sub_initializations_ == 2));
  48   }
  49 }
  50
  51 SegregatedPrefStore::SegregatedPrefStore(
  52     const scoped_refptr<PersistentPrefStore>& default_pref_store,
  53     const scoped_refptr<PersistentPrefStore>& selected_pref_store,
  54     const std::set<std::string>& selected_pref_names)
  55     : default_pref_store_(default_pref_store),
  56       selected_pref_store_(selected_pref_store),
  57       selected_preference_names_(selected_pref_names),
  58       aggregating_observer_(this) {
  59   default_pref_store_->AddObserver(&aggregating_observer_);
  60   selected_pref_store_->AddObserver(&aggregating_observer_);
  61 }
  62
  63 void SegregatedPrefStore::AddObserver(Observer* observer) {
  64   observers_.AddObserver(observer);
  65 }
  66
  67 void SegregatedPrefStore::RemoveObserver(Observer* observer) {
  68   observers_.RemoveObserver(observer);
  69 }
  70
  71 bool SegregatedPrefStore::HasObservers() const {
  72   return observers_.might_have_observers();
  73 }
  74
  75 bool SegregatedPrefStore::IsInitializationComplete() const {
  76   return default_pref_store_->IsInitializationComplete() &&
  77          selected_pref_store_->IsInitializationComplete();
  78 }
  79
  80 bool SegregatedPrefStore::GetValue(const std::string& key,
  81                                    const base::Value** result) const {
  82   return StoreForKey(key)->GetValue(key, result);
  83 }
  84
  85 void SegregatedPrefStore::SetValue(const std::string& key, base::Value* value) {
  86   StoreForKey(key)->SetValue(key, value);
  87 }
  88
  89 void SegregatedPrefStore::RemoveValue(const std::string& key) {
  90   StoreForKey(key)->RemoveValue(key);
  91 }
  92
  93 bool SegregatedPrefStore::GetMutableValue(const std::string& key,
  94                                           base::Value** result) {
  95   return StoreForKey(key)->GetMutableValue(key, result);
  96 }
  97
  98 void SegregatedPrefStore::ReportValueChanged(const std::string& key) {
  99   StoreForKey(key)->ReportValueChanged(key);
 100 }
 101
 102 void SegregatedPrefStore::SetValueSilently(const std::string& key,
 103                                            base::Value* value) {
 104   StoreForKey(key)->SetValueSilently(key, value);
 105 }
 106
 107 bool SegregatedPrefStore::ReadOnly() const {
 108   return selected_pref_store_->ReadOnly() ||
 109          default_pref_store_->ReadOnly();
 110 }
 111
 112 PersistentPrefStore::PrefReadError SegregatedPrefStore::GetReadError() const {
 113   PersistentPrefStore::PrefReadError read_error =
 114       default_pref_store_->GetReadError();
 115   if (read_error == PersistentPrefStore::PREF_READ_ERROR_NONE) {
 116     read_error = selected_pref_store_->GetReadError();
 117     // Ignore NO_FILE from selected_pref_store_.
 118     if (read_error == PersistentPrefStore::PREF_READ_ERROR_NO_FILE)
 119       read_error = PersistentPrefStore::PREF_READ_ERROR_NONE;
 120   }
 121   return read_error;
 122 }
 123
 124 PersistentPrefStore::PrefReadError SegregatedPrefStore::ReadPrefs() {
 125   // Note: Both of these stores own PrefFilters which makes ReadPrefs
 126   // asynchronous. This is okay in this case as only the first call will be
 127   // truly asynchronous, the second call will then unblock the migration in
 128   // TrackedPreferencesMigrator and complete synchronously.
 129   default_pref_store_->ReadPrefs();
 130   PersistentPrefStore::PrefReadError selected_store_read_error =
 131       selected_pref_store_->ReadPrefs();
 132   DCHECK_NE(PersistentPrefStore::PREF_READ_ERROR_ASYNCHRONOUS_TASK_INCOMPLETE,
 133             selected_store_read_error);
 134
 135   return GetReadError();
 136 }
 137
 138 void SegregatedPrefStore::ReadPrefsAsync(ReadErrorDelegate* error_delegate) {
 139   read_error_delegate_.reset(error_delegate);
 140   default_pref_store_->ReadPrefsAsync(NULL);
 141   selected_pref_store_->ReadPrefsAsync(NULL);
 142 }
 143
 144 void SegregatedPrefStore::CommitPendingWrite() {
 145   default_pref_store_->CommitPendingWrite();
 146   selected_pref_store_->CommitPendingWrite();
 147 }
 148
 149 SegregatedPrefStore::~SegregatedPrefStore() {
 150   default_pref_store_->RemoveObserver(&aggregating_observer_);
 151   selected_pref_store_->RemoveObserver(&aggregating_observer_);
 152 }
 153
 154 PersistentPrefStore* SegregatedPrefStore::StoreForKey(const std::string& key) {
 155   return (ContainsKey(selected_preference_names_, key)
 156               ? selected_pref_store_
 157               : default_pref_store_).get();
 158 }
 159
 160 const PersistentPrefStore* SegregatedPrefStore::StoreForKey(
 161     const std::string& key) const {
 162   return (ContainsKey(selected_preference_names_, key)
 163               ? selected_pref_store_
 164               : default_pref_store_).get();
 165 }