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 "base/threading/thread_checker.h"
17#include "content/common/content_export.h"
18#include "content/common/media/media_stream_options.h"
19#include "content/public/renderer/render_frame_observer.h"
20#include "content/renderer/media/media_stream_dispatcher_eventhandler.h"
21
22namespace base {
23class MessageLoopProxy;
24}
25
26namespace content {
27
28// MediaStreamDispatcher is a delegate for the Media Stream API messages.
29// MediaStreams are used by WebKit to open media devices such as Video Capture
30// and Audio input devices.
31// It's the complement of MediaStreamDispatcherHost (owned by
32// BrowserRenderProcessHost).
33class CONTENT_EXPORT MediaStreamDispatcher
34    : public RenderFrameObserver,
35      public base::SupportsWeakPtr<MediaStreamDispatcher> {
36 public:
37  explicit MediaStreamDispatcher(RenderFrame* render_frame);
38  virtual ~MediaStreamDispatcher();
39
40  // Request a new media stream to be created.
41  // This can be used either by WebKit or a plugin.
42  // Note: The event_handler must be valid for as long as the stream exists.
43  virtual void GenerateStream(
44      int request_id,
45      const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler,
46      const StreamOptions& components,
47      const GURL& security_origin);
48
49  // Cancel the request for a new media stream to be created.
50  virtual void CancelGenerateStream(
51      int request_id,
52      const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler);
53
54  // Stop a started device that has been requested by calling GenerateStream.
55  virtual void StopStreamDevice(const StreamDeviceInfo& device_info);
56
57  // Request to enumerate devices.
58  virtual void EnumerateDevices(
59      int request_id,
60      const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler,
61      MediaStreamType type,
62      const GURL& security_origin);
63
64  // Request to stop enumerating devices.
65  void StopEnumerateDevices(
66      int request_id,
67      const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler);
68
69  // Request to open a device.
70  void OpenDevice(
71      int request_id,
72      const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler,
73      const std::string& device_id,
74      MediaStreamType type,
75      const GURL& security_origin);
76
77  // Cancel the request to open a device.
78  virtual void CancelOpenDevice(
79      int request_id,
80      const base::WeakPtr<MediaStreamDispatcherEventHandler>& event_handler);
81
82  // Close a started device. |label| is provided in OnDeviceOpened.
83  void CloseDevice(const std::string& label);
84
85  // Check if the label is a valid stream.
86  virtual bool IsStream(const std::string& label);
87  // Get the video session_id given a label. The label identifies a stream.
88  // index is the index in the video_device_array of the stream.
89  virtual int video_session_id(const std::string& label, int index);
90  // Returns an audio session_id given a label and an index.
91  virtual int audio_session_id(const std::string& label, int index);
92
93  // Returns true if an audio input stream is currently active that was opened
94  // with audio ducking enabled.  This is information is used when playing out
95  // audio so that rendered audio can be excluded from the ducking operation.
96  bool IsAudioDuckingActive() const;
97
98 protected:
99  int GetNextIpcIdForTest() { return next_ipc_id_; }
100
101 private:
102  FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, BasicVideoDevice);
103  FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, TestFailure);
104  FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, CancelGenerateStream);
105  FRIEND_TEST_ALL_PREFIXES(MediaStreamDispatcherTest, CheckDuckingState);
106
107  struct Request;
108
109  // Private class for keeping track of opened devices and who have
110  // opened it.
111  struct Stream;
112
113  // RenderFrameObserver OVERRIDE.
114  virtual void OnDestruct() OVERRIDE;
115  virtual bool Send(IPC::Message* message) OVERRIDE;
116  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
117
118  // Messages from the browser.
119  void OnStreamGenerated(
120      int request_id,
121      const std::string& label,
122      const StreamDeviceInfoArray& audio_array,
123      const StreamDeviceInfoArray& video_array);
124  void OnStreamGenerationFailed(
125      int request_id,
126      content::MediaStreamRequestResult result);
127  void OnDeviceStopped(const std::string& label,
128                       const StreamDeviceInfo& device_info);
129  void OnDevicesEnumerated(
130      int request_id,
131      const StreamDeviceInfoArray& device_array);
132  void OnDeviceOpened(
133      int request_id,
134      const std::string& label,
135      const StreamDeviceInfo& device_info);
136  void OnDeviceOpenFailed(int request_id);
137
138  // Used for DCHECKs so methods calls won't execute in the wrong thread.
139  base::ThreadChecker thread_checker_;
140
141  int next_ipc_id_;
142  typedef std::map<std::string, Stream> LabelStreamMap;
143  LabelStreamMap label_stream_map_;
144
145  // List of calls made to the browser process that have not yet completed or
146  // been canceled.
147  typedef std::list<Request> RequestList;
148  RequestList requests_;
149
150  DISALLOW_COPY_AND_ASSIGN(MediaStreamDispatcher);
151};
152
153}  // namespace content
154
155#endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_DISPATCHER_H_
156