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 <media/AudioSystem.h>
25 #include <utils/Singleton.h>
26
27 #include "AAudioEndpointManager.h"
28 #include "AAudioServiceEndpoint.h"
29 #include <algorithm>
30 #include <mutex>
31 #include <vector>
32
33 #include "core/AudioStreamBuilder.h"
34 #include "AAudioServiceEndpoint.h"
35 #include "AAudioServiceStreamShared.h"
36 #include "AAudioServiceEndpointPlay.h"
37 #include "AAudioServiceEndpointShared.h"
38 #include "AAudioServiceStreamBase.h"
39
40 using namespace android; // TODO just import names needed
41 using namespace aaudio; // TODO just import names needed
42
43 #define BURSTS_PER_BUFFER_DEFAULT 2
44
AAudioServiceEndpointPlay(AAudioService & audioService)45 AAudioServiceEndpointPlay::AAudioServiceEndpointPlay(AAudioService& audioService)
46 : AAudioServiceEndpointShared(
47 new AudioStreamInternalPlay(audioService.asAAudioServiceInterface(), true)) {}
48
open(const aaudio::AAudioStreamRequest & request)49 aaudio_result_t AAudioServiceEndpointPlay::open(const aaudio::AAudioStreamRequest &request) {
50 aaudio_result_t result = AAudioServiceEndpointShared::open(request);
51 if (result == AAUDIO_OK) {
52 mMixer.allocate(getStreamInternal()->getSamplesPerFrame(),
53 getStreamInternal()->getFramesPerBurst());
54
55 int32_t burstsPerBuffer = AudioSystem::getAAudioMixerBurstCount();
56 if (burstsPerBuffer == 0) {
57 mLatencyTuningEnabled = true;
58 burstsPerBuffer = BURSTS_PER_BUFFER_DEFAULT;
59 }
60 int32_t desiredBufferSize = burstsPerBuffer * getStreamInternal()->getFramesPerBurst();
61 getStreamInternal()->setBufferSize(desiredBufferSize);
62 }
63 return result;
64 }
65
66 // Mix data from each application stream and write result to the shared MMAP stream.
callbackLoop()67 void *AAudioServiceEndpointPlay::callbackLoop() {
68 ALOGD("%s() entering >>>>>>>>>>>>>>> MIXER", __func__);
69 aaudio_result_t result = AAUDIO_OK;
70 int64_t timeoutNanos = getStreamInternal()->calculateReasonableTimeout();
71
72 // result might be a frame count
73 while (mCallbackEnabled.load() && getStreamInternal()->isActive() && (result >= 0)) {
74 // Mix data from each active stream.
75 mMixer.clear();
76
77 { // brackets are for lock_guard
78 int index = 0;
79 int64_t mmapFramesWritten = getStreamInternal()->getFramesWritten();
80
81 std::lock_guard <std::mutex> lock(mLockStreams);
82 for (const auto& clientStream : mRegisteredStreams) {
83 int64_t clientFramesRead = 0;
84 bool allowUnderflow = true;
85
86 if (clientStream->isSuspended()) {
87 continue; // dead stream
88 }
89
90 aaudio_stream_state_t state = clientStream->getState();
91 if (state == AAUDIO_STREAM_STATE_STOPPING ||
92 state == AAUDIO_STREAM_STATE_PAUSING) {
93 allowUnderflow = false; // just read what is already in the FIFO
94 } else if (state != AAUDIO_STREAM_STATE_STARTED) {
95 continue; // this stream is not running so skip it.
96 }
97
98 sp<AAudioServiceStreamShared> streamShared =
99 static_cast<AAudioServiceStreamShared *>(clientStream.get());
100
101 {
102 // Lock the AudioFifo to protect against close.
103 std::lock_guard <std::mutex> lock(streamShared->audioDataQueueLock);
104 std::shared_ptr<SharedRingBuffer> audioDataQueue
105 = streamShared->getAudioDataQueue_l();
106 std::shared_ptr<FifoBuffer> fifo;
107 if (audioDataQueue && (fifo = audioDataQueue->getFifoBuffer())) {
108
109 // Determine offset between framePosition in client's stream
110 // vs the underlying MMAP stream.
111 clientFramesRead = fifo->getReadCounter();
112 // These two indices refer to the same frame.
113 int64_t positionOffset = mmapFramesWritten - clientFramesRead;
114 streamShared->setTimestampPositionOffset(positionOffset);
115
116 int32_t framesMixed = mMixer.mix(index, fifo, allowUnderflow);
117
118 if (streamShared->isFlowing()) {
119 // Consider it an underflow if we got less than a burst
120 // after the data started flowing.
121 bool underflowed = allowUnderflow
122 && framesMixed < mMixer.getFramesPerBurst();
123 if (underflowed) {
124 streamShared->incrementXRunCount();
125 }
126 } else if (framesMixed > 0) {
127 // Mark beginning of data flow after a start.
128 streamShared->setFlowing(true);
129 }
130 clientFramesRead = fifo->getReadCounter();
131 }
132 }
133
134 if (clientFramesRead > 0) {
135 // This timestamp represents the completion of data being read out of the
136 // client buffer. It is sent to the client and used in the timing model
137 // to decide when the client has room to write more data.
138 Timestamp timestamp(clientFramesRead, AudioClock::getNanoseconds());
139 streamShared->markTransferTime(timestamp);
140 }
141
142 index++; // just used for labelling tracks in systrace
143 }
144 }
145
146 // Write mixer output to stream using a blocking write.
147 result = getStreamInternal()->write(mMixer.getOutputBuffer(),
148 getFramesPerBurst(), timeoutNanos);
149 if (result == AAUDIO_ERROR_DISCONNECTED) {
150 ALOGD("%s() write() returned AAUDIO_ERROR_DISCONNECTED", __func__);
151 AAudioServiceEndpointShared::handleDisconnectRegisteredStreamsAsync();
152 break;
153 } else if (result != getFramesPerBurst()) {
154 ALOGW("callbackLoop() wrote %d / %d",
155 result, getFramesPerBurst());
156 break;
157 }
158 }
159
160 ALOGD("%s() exiting, enabled = %d, state = %d, result = %d <<<<<<<<<<<<< MIXER",
161 __func__, mCallbackEnabled.load(), getStreamInternal()->getState(), result);
162 return nullptr; // TODO review
163 }
164