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