[rac] Temporarily copy libaddressinput to Chrome.

third_party/libaddressinput/chromium/cpp/src/validating_util.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.
+//
+// An object to wrap data with a checksum and a timestamp. These fields are used
+// to verify that the data is not stale or corrupted. Staleness threshold is 1
+// month.
+
+#ifndef I18N_ADDRESSINPUT_VALIDATING_UTIL_H_
+#define I18N_ADDRESSINPUT_VALIDATING_UTIL_H_
+
+#include <ctime>
+#include <string>
+
+namespace i18n {
+namespace addressinput {
+
+// Wraps data with a checksum and a timestamp. Sample usage:
+//    std::string data  = ...
+//    std::string wrapped = ValidatingUtil::Wrap(data, time(NULL));
+//    Process(wrapped);
+//
+//    std::string unwrapped = wrapped;
+//    if (ValidatingUtil::UnwrapTimestamp(&unwrapped, time(NULL)) &&
+//        ValidatingUtil::UnwrapChecksum(&unwrapped)) {
+//      Process(unwrapped);
+//    }
+class ValidatingUtil {
+ public:
+  // Returns |data| with attached checksum and given |timestamp|.
+  static std::string Wrap(const std::string& data, time_t timestamp);
+
+  // Strips out the timestamp from |data|. Returns |true| if the timestamp is
+  // present, formatted correctly, valid, and recent with respect to |now|.
+  static bool UnwrapTimestamp(std::string* data, time_t now);
+
+  // Strips out the checksum from |data|. Returns |true| if the checksum is
+  // present, formatted correctly, and valid for this data.
+  static bool UnwrapChecksum(std::string* data);
+};
+
+}  // namespace addressinput
+}  // namespace i18n
+
+#endif  // I18N_ADDRESSINPUT_VALIDATING_UTIL_H_