Sanitize PrefStore interface.

chrome/common/json_pref_store.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/common/json_pref_store.h"
 
 #include <algorithm>
 
 #include "base/file_util.h"
 #include "base/values.h"
@@ skipping 12 matching lines @@
       prefs_(new DictionaryValue()),
       read_only_(false),
       writer_(filename, file_message_loop_proxy) {
 }
 
 JsonPrefStore::~JsonPrefStore() {
   if (writer_.HasPendingWrite() && !read_only_)
     writer_.DoScheduledWrite();
 }
 
-PrefStore::PrefReadError JsonPrefStore::ReadPrefs() {
+PrefStore::ReadResult JsonPrefStore::GetValue(const std::string& key,
+                                              Value** result) const {
+  return prefs_->Get(key, result) ? READ_OK : READ_NO_VALUE;
+}
+
+void JsonPrefStore::AddObserver(PrefStore::Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void JsonPrefStore::RemoveObserver(PrefStore::Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+void JsonPrefStore::SetValue(const std::string& key, Value* value) {
+  DCHECK(value);
+  scoped_ptr<Value> new_value(value);
+  Value* old_value = NULL;
+  prefs_->Get(key, &old_value);
+  if (!old_value || !value->Equals(old_value)) {
+    prefs_->Set(key, new_value.release());
+    FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
+  }
+}
+
+void JsonPrefStore::SetValueSilently(const std::string& key, Value* value) {
+  DCHECK(value);
+  scoped_ptr<Value> new_value(value);
+  Value* old_value = NULL;
+  prefs_->Get(key, &old_value);
+  if (!old_value || !value->Equals(old_value))
+    prefs_->Set(key, new_value.release());
+}
+
+void JsonPrefStore::RemoveValue(const std::string& key) {
+  if (prefs_->Remove(key, NULL)) {
+    FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
+  }
+}
+
+PersistentPrefStore::PrefReadError JsonPrefStore::ReadPrefs() {
   if (path_.empty()) {
     read_only_ = true;
     return PREF_READ_ERROR_FILE_NOT_SPECIFIED;
   }
   JSONFileValueSerializer serializer(path_);
 
   int error_code = 0;
   std::string error_msg;
   scoped_ptr<Value> value(serializer.Deserialize(&error_code, &error_msg));
   if (!value.get()) {
@@ skipping 80 matching lines @@
 }
 
 bool JsonPrefStore::SerializeData(std::string* output) {
   // TODO(tc): Do we want to prune webkit preferences that match the default
   // value?
   JSONStringValueSerializer serializer(output);
   serializer.set_pretty_print(true);
   scoped_ptr<DictionaryValue> copy(prefs_->DeepCopyWithoutEmptyChildren());
   return serializer.Serialize(*(copy.get()));
 }