1 // Copyright 2017 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 THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIA_AUDIO_MOJO_AUDIO_OUTPUT_IPC_H_
6 #define THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIA_AUDIO_MOJO_AUDIO_OUTPUT_IPC_H_
7 
8 #include <string>
9 
10 #include "base/callback_helpers.h"
11 #include "base/macros.h"
12 #include "base/memory/weak_ptr.h"
13 #include "base/optional.h"
14 #include "base/single_thread_task_runner.h"
15 #include "base/time/time.h"
16 #include "media/audio/audio_output_ipc.h"
17 #include "media/mojo/mojom/audio_data_pipe.mojom-blink.h"
18 #include "media/mojo/mojom/audio_output_stream.mojom-blink.h"
19 #include "mojo/public/cpp/bindings/pending_receiver.h"
20 #include "mojo/public/cpp/bindings/pending_remote.h"
21 #include "mojo/public/cpp/bindings/receiver.h"
22 #include "mojo/public/cpp/bindings/remote.h"
23 #include "third_party/blink/public/mojom/media/renderer_audio_output_stream_factory.mojom-blink.h"
24 #include "third_party/blink/renderer/modules/modules_export.h"
25 
26 namespace blink {
27 
28 // MojoAudioOutputIPC is a renderer-side class for handling creation,
29 // initialization and control of an output stream. May only be used on a single
30 // thread.
31 class MODULES_EXPORT MojoAudioOutputIPC
32     : public media::AudioOutputIPC,
33       public media::mojom::blink::AudioOutputStreamProviderClient {
34  public:
35   using FactoryAccessorCB = base::RepeatingCallback<
36       blink::mojom::blink::RendererAudioOutputStreamFactory*()>;
37 
38   // |factory_accessor| is required to provide a
39   // RendererAudioOutputStreamFactory* if IPC is possible.
40   MojoAudioOutputIPC(
41       FactoryAccessorCB factory_accessor,
42       scoped_refptr<base::SingleThreadTaskRunner> io_task_runner);
43 
44   ~MojoAudioOutputIPC() override;
45 
46   // AudioOutputIPC implementation.
47   void RequestDeviceAuthorization(media::AudioOutputIPCDelegate* delegate,
48                                   const base::UnguessableToken& session_id,
49                                   const std::string& device_id) override;
50   void CreateStream(
51       media::AudioOutputIPCDelegate* delegate,
52       const media::AudioParameters& params,
53       const base::Optional<base::UnguessableToken>& processing_id) override;
54   void PlayStream() override;
55   void PauseStream() override;
56   void FlushStream() override;
57   void CloseStream() override;
58   void SetVolume(double volume) override;
59 
60   // media::mojom::AudioOutputStreamProviderClient implementation.
61   void Created(
62       mojo::PendingRemote<media::mojom::blink::AudioOutputStream> stream,
63       media::mojom::blink::ReadWriteAudioDataPipePtr data_pipe) override;
64 
65  private:
66   static constexpr double kDefaultVolume = 1.0;
67 
68   using AuthorizationCB = blink::mojom::blink::
69       RendererAudioOutputStreamFactory::RequestDeviceAuthorizationCallback;
70 
71   bool AuthorizationRequested() const;
72   bool StreamCreationRequested() const;
73 
74   void ProviderClientBindingDisconnected(uint32_t disconnect_reason,
75                                          const std::string& description);
76 
77   mojo::PendingReceiver<media::mojom::blink::AudioOutputStreamProvider>
78   MakeProviderReceiver();
79 
80   // Tries to acquire a RendererAudioOutputStreamFactory and requests device
81   // authorization. On failure to aquire a factory, |callback| is destructed
82   // asynchronously.
83   void DoRequestDeviceAuthorization(const base::UnguessableToken& session_id,
84                                     const std::string& device_id,
85                                     AuthorizationCB callback);
86 
87   void ReceivedDeviceAuthorization(
88       base::TimeTicks auth_start_time,
89       media::mojom::blink::OutputDeviceStatus status,
90       const media::AudioParameters& params,
91       const String& device_id) const;
92 
93   const FactoryAccessorCB factory_accessor_;
94 
95   // This is the state that |delegate_| expects the stream to be in. It is
96   // maintained for when the stream is created.
97   enum { kPaused, kPlaying } expected_state_ = kPaused;
98   base::Optional<double> volume_;
99 
100   mojo::Receiver<media::mojom::blink::AudioOutputStreamProviderClient>
101       receiver_{this};
102   mojo::Remote<media::mojom::blink::AudioOutputStreamProvider> stream_provider_;
103   mojo::Remote<media::mojom::blink::AudioOutputStream> stream_;
104   media::AudioOutputIPCDelegate* delegate_ = nullptr;
105   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
106 
107   // To make sure we don't send an "authorization completed" callback for a
108   // stream after it's closed, we use this weak factory.
109   base::WeakPtrFactory<MojoAudioOutputIPC> weak_factory_{this};
110 
111   DISALLOW_COPY_AND_ASSIGN(MojoAudioOutputIPC);
112 };
113 
114 }  // namespace blink
115 
116 #endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIA_AUDIO_MOJO_AUDIO_OUTPUT_IPC_H_
117