chromium/third_party/libaddressinput/src/cpp/src/validating_util.cc

// 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.
//
// ValidatingUtil wraps data with checksum and timestamp. Format:
//
//    timestamp=<timestamp>
//    checksum=<checksum>
//    <data>
//
// The timestamp is the time_t that was returned from time() function. The
// timestamp does not need to be portable because it is written and read only by
// ValidatingUtil. The value is somewhat human-readable: it is the number of
// seconds since the epoch.
//
// The checksum is the 32-character hexadecimal MD5 checksum of <data>. It is
// meant to protect from random file changes on disk.

#include "validating_util.h"

#include <cassert>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <string>

#include "util/md5.h"

namespace i18n {
namespace addressinput {

namespace {

const char kTimestampPrefix[] = …;
const size_t kTimestampPrefixLength = …;

const char kChecksumPrefix[] = …;
const size_t kChecksumPrefixLength = …;

const char kSeparator = …;

// Places the header value into |header_value| parameter and erases the header
// from |data|. Returns |true| if the header format is valid.
bool UnwrapHeader(const char* header_prefix,
                  size_t header_prefix_length,
                  std::string* data,
                  std::string* header_value) { … }

}  // namespace

// static
void ValidatingUtil::Wrap(time_t timestamp, std::string* data) { … }

// static
bool ValidatingUtil::UnwrapTimestamp(std::string* data, time_t now) { … }

// static
bool ValidatingUtil::UnwrapChecksum(std::string* data) { … }

}  // namespace addressinput
}  // namespace i18n