1 // Copyright (c) 2012 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 CONTENT_BROWSER_MEDIA_MEDIA_INTERNALS_H_ 6 #define CONTENT_BROWSER_MEDIA_MEDIA_INTERNALS_H_ 7 8 #include <string> 9 #include <vector> 10 11 #include "base/callback_forward.h" 12 #include "base/compiler_specific.h" 13 #include "base/lazy_instance.h" 14 #include "base/strings/string16.h" 15 #include "base/synchronization/lock.h" 16 #include "base/values.h" 17 #include "content/common/content_export.h" 18 #include "media/audio/audio_logging.h" 19 20 namespace media { 21 class AudioParameters; 22 struct MediaLogEvent; 23 } 24 25 namespace content { 26 27 // This class stores information about currently active media. 28 class CONTENT_EXPORT MediaInternals NON_EXPORTED_BASE(public media::AudioLogFactory)29 : NON_EXPORTED_BASE(public media::AudioLogFactory) { 30 public: 31 static MediaInternals* GetInstance(); 32 33 virtual ~MediaInternals(); 34 35 // Called when a MediaEvent occurs. 36 void OnMediaEvents(int render_process_id, 37 const std::vector<media::MediaLogEvent>& events); 38 39 // Called with the update string. 40 typedef base::Callback<void(const base::string16&)> UpdateCallback; 41 42 // Add/remove update callbacks (see above). Must be called on the IO thread. 43 void AddUpdateCallback(const UpdateCallback& callback); 44 void RemoveUpdateCallback(const UpdateCallback& callback); 45 46 // Sends all cached data to each registered UpdateCallback. 47 void SendEverything(); 48 49 // AudioLogFactory implementation. Safe to call from any thread. 50 virtual scoped_ptr<media::AudioLog> CreateAudioLog( 51 AudioComponent component) OVERRIDE; 52 53 private: 54 friend class AudioLogImpl; 55 friend class MediaInternalsTest; 56 friend struct base::DefaultLazyInstanceTraits<MediaInternals>; 57 58 MediaInternals(); 59 60 // Sends |update| to each registered UpdateCallback. Safe to call from any 61 // thread, but will forward to the IO thread. 62 void SendUpdate(const base::string16& update); 63 64 // Caches |value| under |cache_key| so that future SendEverything() calls will 65 // include the current data. Calls JavaScript |function|(|value|) for each 66 // registered UpdateCallback. SendUpdateAndPurgeCache() is similar but purges 67 // the cache entry after completion instead. 68 void SendUpdateAndCache(const std::string& cache_key, 69 const std::string& function, 70 const base::DictionaryValue* value); 71 void SendUpdateAndPurgeCache(const std::string& cache_key, 72 const std::string& function, 73 const base::DictionaryValue* value); 74 // Must only be accessed on the IO thread. 75 std::vector<UpdateCallback> update_callbacks_; 76 77 // All variables below must be accessed under |lock_|. 78 base::Lock lock_; 79 base::DictionaryValue cached_data_; 80 int owner_ids_[AUDIO_COMPONENT_MAX]; 81 82 DISALLOW_COPY_AND_ASSIGN(MediaInternals); 83 }; 84 85 } // namespace content 86 87 #endif // CONTENT_BROWSER_MEDIA_MEDIA_INTERNALS_H_ 88