1 // Copyright (c) 2012 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 "base/prefs/overlay_user_pref_store.h"
6
7 #include "base/memory/scoped_ptr.h"
8 #include "base/values.h"
9
OverlayUserPrefStore(PersistentPrefStore * underlay)10 OverlayUserPrefStore::OverlayUserPrefStore(
11 PersistentPrefStore* underlay)
12 : underlay_(underlay) {
13 underlay_->AddObserver(this);
14 }
15
IsSetInOverlay(const std::string & key) const16 bool OverlayUserPrefStore::IsSetInOverlay(const std::string& key) const {
17 return overlay_.GetValue(key, NULL);
18 }
19
AddObserver(PrefStore::Observer * observer)20 void OverlayUserPrefStore::AddObserver(PrefStore::Observer* observer) {
21 observers_.AddObserver(observer);
22 }
23
RemoveObserver(PrefStore::Observer * observer)24 void OverlayUserPrefStore::RemoveObserver(PrefStore::Observer* observer) {
25 observers_.RemoveObserver(observer);
26 }
27
HasObservers() const28 bool OverlayUserPrefStore::HasObservers() const {
29 return observers_.might_have_observers();
30 }
31
IsInitializationComplete() const32 bool OverlayUserPrefStore::IsInitializationComplete() const {
33 return underlay_->IsInitializationComplete();
34 }
35
GetValue(const std::string & key,const base::Value ** result) const36 bool OverlayUserPrefStore::GetValue(const std::string& key,
37 const base::Value** result) const {
38 // If the |key| shall NOT be stored in the overlay store, there must not
39 // be an entry.
40 DCHECK(ShallBeStoredInOverlay(key) || !overlay_.GetValue(key, NULL));
41
42 if (overlay_.GetValue(key, result))
43 return true;
44 return underlay_->GetValue(GetUnderlayKey(key), result);
45 }
46
GetMutableValue(const std::string & key,base::Value ** result)47 bool OverlayUserPrefStore::GetMutableValue(const std::string& key,
48 base::Value** result) {
49 if (!ShallBeStoredInOverlay(key))
50 return underlay_->GetMutableValue(GetUnderlayKey(key), result);
51
52 if (overlay_.GetValue(key, result))
53 return true;
54
55 // Try to create copy of underlay if the overlay does not contain a value.
56 base::Value* underlay_value = NULL;
57 if (!underlay_->GetMutableValue(GetUnderlayKey(key), &underlay_value))
58 return false;
59
60 *result = underlay_value->DeepCopy();
61 overlay_.SetValue(key, *result);
62 return true;
63 }
64
SetValue(const std::string & key,base::Value * value)65 void OverlayUserPrefStore::SetValue(const std::string& key,
66 base::Value* value) {
67 if (!ShallBeStoredInOverlay(key)) {
68 underlay_->SetValue(GetUnderlayKey(key), value);
69 return;
70 }
71
72 if (overlay_.SetValue(key, value))
73 ReportValueChanged(key);
74 }
75
SetValueSilently(const std::string & key,base::Value * value)76 void OverlayUserPrefStore::SetValueSilently(const std::string& key,
77 base::Value* value) {
78 if (!ShallBeStoredInOverlay(key)) {
79 underlay_->SetValueSilently(GetUnderlayKey(key), value);
80 return;
81 }
82
83 overlay_.SetValue(key, value);
84 }
85
RemoveValue(const std::string & key)86 void OverlayUserPrefStore::RemoveValue(const std::string& key) {
87 if (!ShallBeStoredInOverlay(key)) {
88 underlay_->RemoveValue(GetUnderlayKey(key));
89 return;
90 }
91
92 if (overlay_.RemoveValue(key))
93 ReportValueChanged(key);
94 }
95
ReadOnly() const96 bool OverlayUserPrefStore::ReadOnly() const {
97 return false;
98 }
99
GetReadError() const100 PersistentPrefStore::PrefReadError OverlayUserPrefStore::GetReadError() const {
101 return PersistentPrefStore::PREF_READ_ERROR_NONE;
102 }
103
ReadPrefs()104 PersistentPrefStore::PrefReadError OverlayUserPrefStore::ReadPrefs() {
105 // We do not read intentionally.
106 OnInitializationCompleted(true);
107 return PersistentPrefStore::PREF_READ_ERROR_NONE;
108 }
109
ReadPrefsAsync(ReadErrorDelegate * error_delegate_raw)110 void OverlayUserPrefStore::ReadPrefsAsync(
111 ReadErrorDelegate* error_delegate_raw) {
112 scoped_ptr<ReadErrorDelegate> error_delegate(error_delegate_raw);
113 // We do not read intentionally.
114 OnInitializationCompleted(true);
115 }
116
CommitPendingWrite()117 void OverlayUserPrefStore::CommitPendingWrite() {
118 underlay_->CommitPendingWrite();
119 // We do not write our content intentionally.
120 }
121
ReportValueChanged(const std::string & key)122 void OverlayUserPrefStore::ReportValueChanged(const std::string& key) {
123 FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
124 }
125
OnPrefValueChanged(const std::string & key)126 void OverlayUserPrefStore::OnPrefValueChanged(const std::string& key) {
127 if (!overlay_.GetValue(GetOverlayKey(key), NULL))
128 ReportValueChanged(GetOverlayKey(key));
129 }
130
OnInitializationCompleted(bool succeeded)131 void OverlayUserPrefStore::OnInitializationCompleted(bool succeeded) {
132 FOR_EACH_OBSERVER(PrefStore::Observer, observers_,
133 OnInitializationCompleted(succeeded));
134 }
135
RegisterOverlayPref(const std::string & key)136 void OverlayUserPrefStore::RegisterOverlayPref(const std::string& key) {
137 RegisterOverlayPref(key, key);
138 }
139
RegisterOverlayPref(const std::string & overlay_key,const std::string & underlay_key)140 void OverlayUserPrefStore::RegisterOverlayPref(
141 const std::string& overlay_key,
142 const std::string& underlay_key) {
143 DCHECK(!overlay_key.empty()) << "Overlay key is empty";
144 DCHECK(overlay_to_underlay_names_map_.find(overlay_key) ==
145 overlay_to_underlay_names_map_.end()) <<
146 "Overlay key already registered";
147 DCHECK(!underlay_key.empty()) << "Underlay key is empty";
148 DCHECK(underlay_to_overlay_names_map_.find(underlay_key) ==
149 underlay_to_overlay_names_map_.end()) <<
150 "Underlay key already registered";
151 overlay_to_underlay_names_map_[overlay_key] = underlay_key;
152 underlay_to_overlay_names_map_[underlay_key] = overlay_key;
153 }
154
~OverlayUserPrefStore()155 OverlayUserPrefStore::~OverlayUserPrefStore() {
156 underlay_->RemoveObserver(this);
157 }
158
GetOverlayKey(const std::string & underlay_key) const159 const std::string& OverlayUserPrefStore::GetOverlayKey(
160 const std::string& underlay_key) const {
161 NamesMap::const_iterator i =
162 underlay_to_overlay_names_map_.find(underlay_key);
163 return i != underlay_to_overlay_names_map_.end() ? i->second : underlay_key;
164 }
165
GetUnderlayKey(const std::string & overlay_key) const166 const std::string& OverlayUserPrefStore::GetUnderlayKey(
167 const std::string& overlay_key) const {
168 NamesMap::const_iterator i =
169 overlay_to_underlay_names_map_.find(overlay_key);
170 return i != overlay_to_underlay_names_map_.end() ? i->second : overlay_key;
171 }
172
ShallBeStoredInOverlay(const std::string & key) const173 bool OverlayUserPrefStore::ShallBeStoredInOverlay(
174 const std::string& key) const {
175 return overlay_to_underlay_names_map_.find(key) !=
176 overlay_to_underlay_names_map_.end();
177 }
178