[rac] Temporarily copy libaddressinput to Chrome.

third_party/libaddressinput/chromium/cpp/src/validating_storage.h

+// Copyright (C) 2013 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// A wrapper object for Storage that stores data with a checksum and a
+// timestamp. The existence of checksum and timestamp fields is transparent to
+// the user of the object.
+
+#ifndef I18N_ADDRESSINPUT_VALIDATING_STORAGE_H_
+#define I18N_ADDRESSINPUT_VALIDATING_STORAGE_H_
+
+#include <libaddressinput/storage.h>
+#include <libaddressinput/util/basictypes.h>
+#include <libaddressinput/util/scoped_ptr.h>
+
+#include <string>
+
+namespace i18n {
+namespace addressinput {
+
+// Wraps Storage to add checksum and timestamp to stored data. Sample usage:
+//    Storage file_storage = ...;
+//    scoped_ptr<Storage> storage(new ValidatingStorage(file_storage));
+//    storage->Put("key", "data");
+//    scoped_ptr<Storage::Callback> data_ready(BuildCallback(
+//        this, &MyClass::OnDataReady));
+//    storage->Get("key", *data_ready);
+class ValidatingStorage : public Storage {
+ public:
+  // Takes ownership of |storage|.
+  explicit ValidatingStorage(Storage* storage);
+  virtual ~ValidatingStorage();
+
+  // Storage implementation.
+  virtual void Put(const std::string& key, const std::string& data);
+  virtual void Get(const std::string& key, const Callback& data_ready) const;
+
+ private:
+  // The storage being wrapped.
+  scoped_ptr<Storage> wrapped_storage_;
+
+  DISALLOW_COPY_AND_ASSIGN(ValidatingStorage);
+};
+
+}  // namespace addressinput
+}  // namespace i18n
+
+#endif  // I18N_ADDRESSINPUT_VALIDATING_STORAGE_H_