third_party/chromium/media/base/key_system_names.cc

// Copyright 2013 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 "media/base/key_system_names.h"

namespace media {

const char kClearKey[] = "org.w3.clearkey";
const char kExternalClearKey[] = "org.chromium.externalclearkey";

bool IsClearKey(const std::string& key_system) {
  return key_system == kClearKey;
}

bool IsSubKeySystemOf(const std::string& key_system, const std::string& base) {
  std::string prefix = base + '.';
  return key_system.substr(0, prefix.size()) == prefix;
}

bool IsExternalClearKey(const std::string& key_system) {
  return key_system == kExternalClearKey ||
         IsSubKeySystemOf(key_system, kExternalClearKey);
}

}  // namespace media