1/*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef AAUDIO_AAUDIO_SERVICE_STREAM_MMAP_H
18#define AAUDIO_AAUDIO_SERVICE_STREAM_MMAP_H
19
20#include <atomic>
21
22#include <media/audiohal/StreamHalInterface.h>
23#include <media/MmapStreamCallback.h>
24#include <media/MmapStreamInterface.h>
25#include <utils/RefBase.h>
26#include <utils/String16.h>
27#include <utils/Vector.h>
28
29#include "binding/AAudioServiceMessage.h"
30#include "AAudioServiceStreamBase.h"
31#include "binding/AudioEndpointParcelable.h"
32#include "SharedMemoryProxy.h"
33#include "TimestampScheduler.h"
34#include "utility/MonotonicCounter.h"
35
36namespace aaudio {
37
38    /**
39     * Manage one memory mapped buffer that originated from a HAL.
40     */
41class AAudioServiceStreamMMAP
42    : public AAudioServiceStreamBase
43    , public android::MmapStreamCallback {
44
45public:
46    AAudioServiceStreamMMAP();
47    virtual ~AAudioServiceStreamMMAP();
48
49
50    aaudio_result_t open(const aaudio::AAudioStreamRequest &request,
51                                 aaudio::AAudioStreamConfiguration &configurationOutput) override;
52
53    /**
54     * Start the flow of audio data.
55     *
56     * This is not guaranteed to be synchronous but it currently is.
57     * An AAUDIO_SERVICE_EVENT_STARTED will be sent to the client when complete.
58     */
59    aaudio_result_t start() override;
60
61    /**
62     * Stop the flow of data so that start() can resume without loss of data.
63     *
64     * This is not guaranteed to be synchronous but it currently is.
65     * An AAUDIO_SERVICE_EVENT_PAUSED will be sent to the client when complete.
66    */
67    aaudio_result_t pause() override;
68
69    aaudio_result_t stop() override;
70
71    /**
72     *  Discard any data held by the underlying HAL or Service.
73     *
74     * This is not guaranteed to be synchronous but it currently is.
75     * An AAUDIO_SERVICE_EVENT_FLUSHED will be sent to the client when complete.
76     */
77    aaudio_result_t flush() override;
78
79    aaudio_result_t close() override;
80
81    /**
82     * Send a MMAP/NOIRQ buffer timestamp to the client.
83     */
84    aaudio_result_t sendCurrentTimestamp();
85
86    // -------------- Callback functions ---------------------
87    void onTearDown() override;
88
89    void onVolumeChanged(audio_channel_mask_t channels,
90                         android::Vector<float> values) override;
91
92    void onRoutingChanged(audio_port_handle_t deviceId) override;
93
94protected:
95
96    aaudio_result_t getDownDataDescription(AudioEndpointParcelable &parcelable) override;
97
98    aaudio_result_t getFreeRunningPosition(int64_t *positionFrames, int64_t *timeNanos) override;
99
100private:
101    // This proxy class was needed to prevent a crash in AudioFlinger
102    // when the stream was closed.
103    class MyMmapStreamCallback : public android::MmapStreamCallback {
104    public:
105        explicit MyMmapStreamCallback(android::MmapStreamCallback &serviceCallback)
106            : mServiceCallback(serviceCallback){}
107        virtual ~MyMmapStreamCallback() = default;
108
109        void onTearDown() override {
110            mServiceCallback.onTearDown();
111        };
112
113        void onVolumeChanged(audio_channel_mask_t channels, android::Vector<float> values) override
114        {
115            mServiceCallback.onVolumeChanged(channels, values);
116        };
117
118        void onRoutingChanged(audio_port_handle_t deviceId) override {
119            mServiceCallback.onRoutingChanged(deviceId);
120        };
121
122    private:
123        android::MmapStreamCallback &mServiceCallback;
124    };
125
126    android::sp<MyMmapStreamCallback>   mMmapStreamCallback;
127    MonotonicCounter                    mFramesWritten;
128    MonotonicCounter                    mFramesRead;
129    int32_t                             mPreviousFrameCounter = 0;   // from HAL
130    int                                 mAudioDataFileDescriptor = -1;
131
132    // Interface to the AudioFlinger MMAP support.
133    android::sp<android::MmapStreamInterface> mMmapStream;
134    struct audio_mmap_buffer_info             mMmapBufferinfo;
135    android::MmapStreamInterface::Client      mMmapClient;
136    audio_port_handle_t                       mPortHandle = -1; // TODO review best default
137};
138
139} // namespace aaudio
140
141#endif //AAUDIO_AAUDIO_SERVICE_STREAM_MMAP_H
142