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 #define LOG_TAG "AAudioServiceEndpointPlay"
18 //#define LOG_NDEBUG 0
19 #include <utils/Log.h>
20
21 #include <assert.h>
22 #include <map>
23 #include <mutex>
24 #include <utils/Singleton.h>
25
26 #include "AAudioEndpointManager.h"
27 #include "AAudioServiceEndpoint.h"
28 #include <algorithm>
29 #include <mutex>
30 #include <vector>
31
32 #include "core/AudioStreamBuilder.h"
33 #include "AAudioServiceEndpoint.h"
34 #include "AAudioServiceStreamShared.h"
35 #include "AAudioServiceEndpointPlay.h"
36 #include "AAudioServiceEndpointShared.h"
37
38 using namespace android; // TODO just import names needed
39 using namespace aaudio; // TODO just import names needed
40
41 #define BURSTS_PER_BUFFER_DEFAULT 2
42
AAudioServiceEndpointPlay(AAudioService & audioService)43 AAudioServiceEndpointPlay::AAudioServiceEndpointPlay(AAudioService &audioService)
44 : mStreamInternalPlay(audioService, true) {
45 mStreamInternal = &mStreamInternalPlay;
46 }
47
~AAudioServiceEndpointPlay()48 AAudioServiceEndpointPlay::~AAudioServiceEndpointPlay() {
49 }
50
open(const aaudio::AAudioStreamRequest & request)51 aaudio_result_t AAudioServiceEndpointPlay::open(const aaudio::AAudioStreamRequest &request) {
52 aaudio_result_t result = AAudioServiceEndpointShared::open(request);
53 if (result == AAUDIO_OK) {
54 mMixer.allocate(getStreamInternal()->getSamplesPerFrame(),
55 getStreamInternal()->getFramesPerBurst());
56
57 int32_t burstsPerBuffer = AAudioProperty_getMixerBursts();
58 if (burstsPerBuffer == 0) {
59 mLatencyTuningEnabled = true;
60 burstsPerBuffer = BURSTS_PER_BUFFER_DEFAULT;
61 }
62 int32_t desiredBufferSize = burstsPerBuffer * getStreamInternal()->getFramesPerBurst();
63 getStreamInternal()->setBufferSize(desiredBufferSize);
64 }
65 return result;
66 }
67
68 // Mix data from each application stream and write result to the shared MMAP stream.
callbackLoop()69 void *AAudioServiceEndpointPlay::callbackLoop() {
70 aaudio_result_t result = AAUDIO_OK;
71 int64_t timeoutNanos = getStreamInternal()->calculateReasonableTimeout();
72
73 // result might be a frame count
74 while (mCallbackEnabled.load() && getStreamInternal()->isActive() && (result >= 0)) {
75 // Mix data from each active stream.
76 mMixer.clear();
77
78 { // brackets are for lock_guard
79 int index = 0;
80 int64_t mmapFramesWritten = getStreamInternal()->getFramesWritten();
81
82 std::lock_guard <std::mutex> lock(mLockStreams);
83 for (const auto clientStream : mRegisteredStreams) {
84 int64_t clientFramesRead = 0;
85
86 if (!clientStream->isRunning()) {
87 continue;
88 }
89
90 sp<AAudioServiceStreamShared> streamShared =
91 static_cast<AAudioServiceStreamShared *>(clientStream.get());
92
93 {
94 // Lock the AudioFifo to protect against close.
95 std::lock_guard <std::mutex> lock(streamShared->getAudioDataQueueLock());
96
97 FifoBuffer *fifo = streamShared->getAudioDataFifoBuffer_l();
98 if (fifo != nullptr) {
99
100 // Determine offset between framePosition in client's stream
101 // vs the underlying MMAP stream.
102 clientFramesRead = fifo->getReadCounter();
103 // These two indices refer to the same frame.
104 int64_t positionOffset = mmapFramesWritten - clientFramesRead;
105 streamShared->setTimestampPositionOffset(positionOffset);
106
107 float volume = 1.0; // to match legacy volume
108 bool underflowed = mMixer.mix(index, fifo, volume);
109 if (underflowed) {
110 streamShared->incrementXRunCount();
111 }
112 clientFramesRead = fifo->getReadCounter();
113 }
114 }
115
116 if (clientFramesRead > 0) {
117 // This timestamp represents the completion of data being read out of the
118 // client buffer. It is sent to the client and used in the timing model
119 // to decide when the client has room to write more data.
120 Timestamp timestamp(clientFramesRead, AudioClock::getNanoseconds());
121 streamShared->markTransferTime(timestamp);
122 }
123
124 index++; // just used for labelling tracks in systrace
125 }
126 }
127
128 // Write mixer output to stream using a blocking write.
129 result = getStreamInternal()->write(mMixer.getOutputBuffer(),
130 getFramesPerBurst(), timeoutNanos);
131 if (result == AAUDIO_ERROR_DISCONNECTED) {
132 AAudioServiceEndpointShared::disconnectRegisteredStreams();
133 break;
134 } else if (result != getFramesPerBurst()) {
135 ALOGW("AAudioServiceEndpoint(): callbackLoop() wrote %d / %d",
136 result, getFramesPerBurst());
137 break;
138 }
139 }
140
141 return NULL; // TODO review
142 }
143