chrome/browser/media/media_device_id_salt.h

   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 #ifndef CHROME_BROWSER_MEDIA_MEDIA_DEVICE_ID_SALT_H_
   6 #define CHROME_BROWSER_MEDIA_MEDIA_DEVICE_ID_SALT_H_
   7
   8 #include <string>
   9
  10 #include "base/prefs/pref_member.h"
  11 #include "components/user_prefs/pref_registry_syncable.h"
  12
  13 class PrefService;
  14
  15 // MediaDeviceIDSalt is responsible for creating and retrieving a salt string
  16 // that is used for creating MediaSource IDs that can be cached by a web
  17 // service. If the cache is cleared, the  MediaSourceIds are invalidated.
  18 class MediaDeviceIDSalt {
  19  public:
  20   MediaDeviceIDSalt(PrefService* pref_service,
  21                     bool incognito);
  22   ~MediaDeviceIDSalt();
  23   void ShutdownOnUIThread();
  24
  25   std::string GetSalt() const;
  26
  27   static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
  28   static void Reset(PrefService* pref_service);
  29
  30  private:
  31   // |incognito_salt_| is initialized in ctor on UI thread but only read
  32   //  on the IO thread.
  33   std::string incognito_salt_;
  34   mutable StringPrefMember media_device_id_salt_;
  35
  36   DISALLOW_COPY_AND_ASSIGN(MediaDeviceIDSalt);
  37 };
  38
  39 #endif  // CHROME_BROWSER_MEDIA_MEDIA_DEVICE_ID_SALT_H_