content/renderer/media/media_stream_dispatcher.h

   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_RENDERER_MEDIA_MEDIA_STREAM_DISPATCHER_H_
   6 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_DISPATCHER_H_
   7
   8 #include <list>
   9 #include <map>
  10 #include <string>
  11
  12 #include "base/basictypes.h"
  13 #include "base/gtest_prod_util.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "content/common/content_export.h"
  17 #include "content/common/media/media_stream_options.h"
  18 #include "content/public/renderer/render_view_observer.h"
  19 #include "content/renderer/media/media_stream_dispatcher_eventhandler.h"
  20
  21 namespace base {
  22 class MessageLoopProxy;
  23 }
  24
  25 namespace content {
  26
  27 class RenderViewImpl;
  28
  29 // MediaStreamDispatcher is a delegate for the Media Stream API messages.
  30 // MediaStreams are used by WebKit to open media devices such as Video Capture
  31 // and Audio input devices.
  32 // It's the complement of MediaStreamDispatcherHost (owned by
  33 // BrowserRenderProcessHost).
  34 class CONTENT_EXPORT MediaStreamDispatcher
  35     : public RenderViewObserver,
  36       public base::SupportsWeakPtr<MediaStreamDispatcher> {
  37  public:
  38   explicit MediaStreamDispatcher(RenderViewImpl* render_view);
  39   virtual ~MediaStreamDispatcher();
  40
  41   // Request a new media stream to be created.
  42   // This can be used either by WebKit or a plugin.
  43   // Note: The event_handler must be valid for as long as the stream exists.
  44   virtual void GenerateStream(
  45       int request_id,
  46       const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler,
  47       const StreamOptions& components,
  48       const GURL& security_origin);
  49
  50   // Cancel the request for a new media stream to be created.
  51   virtual void CancelGenerateStream(int request_id);
  52
  53   // Stop a started stream. Label is the label provided in OnStreamGenerated.
  54   virtual void StopStream(const std::string& label);
  55
  56   // Request to enumerate devices.
  57   void EnumerateDevices(
  58       int request_id,
  59       const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler,
  60       MediaStreamType type,
  61       const GURL& security_origin);
  62
  63   // Request to stop enumerating devices.
  64   void StopEnumerateDevices(
  65       int request_id,
  66       const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler);
  67
  68   // Request to open a device.
  69   void OpenDevice(
  70       int request_id,
  71       const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler,
  72       const std::string& device_id,
  73       MediaStreamType type,
  74       const GURL& security_origin);
  75
  76   // Close a started device. |label| is provided in OnDeviceOpened.
  77   void CloseDevice(const std::string& label);
  78
  79   // Check if the label is a valid stream.
  80   virtual bool IsStream(const std::string& label);
  81   // Get the video session_id given a label. The label identifies a stream.
  82   // index is the index in the video_device_array of the stream.
  83   virtual int video_session_id(const std::string& label, int index);
  84   // Returns an audio session_id given a label and an index.
  85   virtual int audio_session_id(const std::string& label, int index);
  86
  87  private:
  88   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, BasicStream);
  89   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, BasicStreamForDevice);
  90   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, BasicVideoDevice);
  91   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, TestFailure);
  92   FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, CancelGenerateStream);
  93
  94   struct Request;
  95
  96   // Private class for keeping track of opened devices and who have
  97   // opened it.
  98   struct Stream;
  99
 100   struct EnumerationRequest {
 101     EnumerationRequest(
 102         const base::WeakPtr<MediaStreamDispatcherEventHandler>& handler,
 103         int request_id);
 104     ~EnumerationRequest();
 105
 106     base::WeakPtr<MediaStreamDispatcherEventHandler> handler;
 107     int request_id;
 108   };
 109
 110   // List of requests made to EnumerateDevices.
 111   typedef std::list<EnumerationRequest> EnumerationRequestList;
 112
 113   struct EnumerationState {
 114     EnumerationState();
 115     ~EnumerationState();
 116
 117     struct CachedDevices;
 118
 119     // If |ipc_id| >= 0, then we've started.
 120     int ipc_id;
 121     scoped_ptr<CachedDevices> cached_devices;
 122     EnumerationRequestList requests;
 123   };
 124
 125   // Messages from the browser.
 126   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 127   void OnStreamGenerated(
 128       int request_id,
 129       const std::string& label,
 130       const StreamDeviceInfoArray& audio_array,
 131       const StreamDeviceInfoArray& video_array);
 132   void OnStreamGenerationFailed(int request_id);
 133   void OnDevicesEnumerated(
 134       int request_id,
 135       const std::string& label,
 136       const StreamDeviceInfoArray& device_array);
 137   void OnDevicesEnumerationFailed(int request_id);
 138   void OnDeviceOpened(
 139       int request_id,
 140       const std::string& label,
 141       const StreamDeviceInfo& device_info);
 142   void OnDeviceOpenFailed(int request_id);
 143
 144   void RemoveEnumerationRequest(
 145       int request_id,
 146       const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler,
 147       EnumerationState* state);
 148
 149   // Used for DCHECKs so methods calls won't execute in the wrong thread.
 150   scoped_refptr<base::MessageLoopProxy> main_loop_;
 151
 152   int next_ipc_id_;
 153   typedef std::map<std::string, Stream> LabelStreamMap;
 154   LabelStreamMap label_stream_map_;
 155
 156   EnumerationState audio_enumeration_state_;
 157   EnumerationState video_enumeration_state_;
 158
 159   // List of calls made to GenerateStream that have not yet completed.
 160   typedef std::list<Request> RequestList;
 161   RequestList requests_;
 162
 163   DISALLOW_COPY_AND_ASSIGN(MediaStreamDispatcher);
 164 };
 165
 166 }  // namespace content
 167
 168 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_DISPATCHER_H_