AAudioServiceStreamShared.h revision a5222e298c294781067950a7cc319d3278fa845a 
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_SHARED_H
18#define AAUDIO_AAUDIO_SERVICE_STREAM_SHARED_H
19
20#include "fifo/FifoBuffer.h"
21#include "binding/AAudioServiceMessage.h"
22#include "binding/AAudioStreamRequest.h"
23#include "binding/AAudioStreamConfiguration.h"
24
25#include "AAudioService.h"
26#include "AAudioServiceStreamBase.h"
27
28namespace aaudio {
29
30// We expect the queue to only have a few commands.
31// This should be way more than we need.
32#define QUEUE_UP_CAPACITY_COMMANDS (128)
33
34class AAudioEndpointManager;
35class AAudioServiceEndpoint;
36class SharedRingBuffer;
37
38/**
39 * One of these is created for every MODE_SHARED stream in the AAudioService.
40 *
41 * Each Shared stream will register itself with an AAudioServiceEndpoint when it is opened.
42 */
43class AAudioServiceStreamShared : public AAudioServiceStreamBase {
44
45public:
46    AAudioServiceStreamShared(android::AAudioService &aAudioService);
47    virtual ~AAudioServiceStreamShared() = default;
48
49    static std::string dumpHeader();
50
51    std::string dump() const override;
52
53    aaudio_result_t open(const aaudio::AAudioStreamRequest &request,
54                         aaudio::AAudioStreamConfiguration &configurationOutput) override;
55
56    /**
57     * Start the flow of audio data.
58     *
59     * This is not guaranteed to be synchronous but it currently is.
60     * An AAUDIO_SERVICE_EVENT_STARTED will be sent to the client when complete.
61     */
62    aaudio_result_t start() override;
63
64    /**
65     * Stop the flow of data so that start() can resume without loss of data.
66     *
67     * This is not guaranteed to be synchronous but it currently is.
68     * An AAUDIO_SERVICE_EVENT_PAUSED will be sent to the client when complete.
69    */
70    aaudio_result_t pause() override;
71
72    /**
73     * Stop the flow of data after data in buffer has played.
74     */
75    aaudio_result_t stop() override;
76
77    /**
78     *  Discard any data held by the underlying HAL or Service.
79     *
80     * This is not guaranteed to be synchronous but it currently is.
81     * An AAUDIO_SERVICE_EVENT_FLUSHED will be sent to the client when complete.
82     */
83    aaudio_result_t flush() override;
84
85    aaudio_result_t close() override;
86
87    android::FifoBuffer *getDataFifoBuffer() { return mAudioDataQueue->getFifoBuffer(); }
88
89    /* Keep a record of when a buffer transfer completed.
90     * This allows for a more accurate timing model.
91     */
92    void markTransferTime(Timestamp &timestamp);
93
94    void setTimestampPositionOffset(int64_t deltaFrames) {
95        mTimestampPositionOffset.store(deltaFrames);
96    }
97
98    void incrementXRunCount() {
99        mXRunCount++;
100    }
101
102    int32_t getXRunCount() const {
103        return mXRunCount.load();
104    }
105
106protected:
107
108    aaudio_result_t getDownDataDescription(AudioEndpointParcelable &parcelable) override;
109
110    aaudio_result_t getFreeRunningPosition(int64_t *positionFrames, int64_t *timeNanos) override;
111
112    virtual aaudio_result_t getHardwareTimestamp(int64_t *positionFrames,
113                                                 int64_t *timeNanos) override;
114
115    /**
116     * @param requestedCapacityFrames
117     * @param framesPerBurst
118     * @return capacity or negative error
119     */
120    static int32_t calculateBufferCapacity(int32_t requestedCapacityFrames,
121                                            int32_t framesPerBurst);
122
123private:
124    android::AAudioService  &mAudioService;
125    AAudioServiceEndpoint   *mServiceEndpoint = nullptr;
126    SharedRingBuffer        *mAudioDataQueue = nullptr;
127
128    std::atomic<int64_t>     mTimestampPositionOffset;
129    std::atomic<int32_t>     mXRunCount;
130};
131
132} /* namespace aaudio */
133
134#endif //AAUDIO_AAUDIO_SERVICE_STREAM_SHARED_H
135