1// Copyright 2013 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 "media/cdm/key_system_names.h"
6
7#include <string>
8
9namespace media {
10
11const char kClearKey[] = "org.w3.clearkey";
12const char kExternalClearKey[] = "org.chromium.externalclearkey";
13
14static bool IsParentKeySystemOf(const std::string& parent_key_system,
15                                const std::string& key_system) {
16  std::string prefix = parent_key_system + '.';
17  return key_system.substr(0, prefix.size()) == prefix;
18}
19
20bool IsExternalClearKey(const std::string& key_system) {
21  return key_system == kExternalClearKey ||
22         IsParentKeySystemOf(kExternalClearKey, key_system);
23}
24
25}  // namespace media
26