Audio HAL: Factorize V2 and V4 like libaudiohal

Use the same technique developed for the simpler libaudiohal to
factorize the audio HAL impl.

Generated with script:

set -euo pipefail

cd hardware/interfaces/audio

# Make 2.0 and 4.0 files mostly identical by removing all 2.0, V4.0...
# and replacing it by CPP_VERSION and FILE_VERSION
# This allow both implementation to be mostly identical, except for code difference
# Also remove IncludeGuard.h as it will be included from compiler flag
# Also update license to 2018
find -name *.cpp -o -name *h |
    grep -v -e service.cpp |
    xargs sed -Ei \
        -e 's/(#.*)V[42]_0_(.*_H_?)$/\1\2/' \
        -e 's/(LOG_TAG.*)[24]_0/\1/' \
        -e '/#ifndef AUDIO_HAL_VERSION/,/#endif/d' \
        -e '/^#.*def.*AUDIO_HAL_VERSION\b/d' \
        -e's/V[42]_0/CPP_VERSION/' \
        -e 's/(#include ).(android.*)[24].0(.*).$/\1PATH(\2FILE_VERSION\3)/' \
        -e 's|(#include) .(.*)[24].0/(default/.*).$|\1 "\2\3"|' \
        -e 's/\bAUDIO_HAL_VERSION\b/CPP_VERSION/' \
        -e '/IncludeGuard.h/d' \
        -e 's/(Copyright .C. 201)./\18/'

# set MAJOR_VERSION instead of having a different macro for each version
# this allow to do preprocessor arithmetic (eg: MAJOR_VERSION >= 4)
for v in 2 4; do
    find -ipath '*/'$v'.0/*/Android.bp' |
        xargs sed -i -e '/cflags:/,/^$/d' -e '/vndk/{:a;/}/!{N;ba};d}' -e '$i\
    cflags: [\
        "-DMAJOR_VERSION='$v'",\
        "-DMINOR_VERSION=0",\
        "-include common/all-versions/VersionMacro.h",\
    ]'; done

# replace# ifdef VERSION_X by #if MAJOR_VERSION == X
find -path *all-versions/*.h |
    xargs sed -Ei -e 's/def.*AUDIO_HAL_VERSION_([24])_0.*/ MAJOR_VERSION == \1/' \
                  -e 'T;s/ +/ /'

# copy all-versions impl in each version impl
find -path '*/[24].0/*.[hc]*' |
    grep -ve all-versions -e test |
    xargs -P99 -n4 sed -i -Ee '/include <.*all-versions.default/!b' \
        -e 's#.*<#find -path */#' -e 's/>$/|xargs tail -n +16/' -e e

# remove all-versions impl
rm -r {core,effect}/all-versions/

# merge version impl into a single all-version
for dir in core/*.0/vts/functional/*.0/ ;do
    dest=$(echo $dir | sed 's#/..0/#/all-versions/#')
    mkdir -p $dest
    mv -T $dir $dest
done

find -mindepth 3 -path '*/2.0/*' -a \( -name '*cpp' -o -name '*h' \) |
    grep -v 'all-versions' |
    sed -E 'h;s/2/4/g;H;s/4.0/all-versions/;s/4.0//;H;g;s/\n/ /g;'|
    xargs -P99 -L1 sh -c '
        set -euo pipefail
        mkdir -p $(dirname $2);
        diff --old-group-format="#if MAJOR_VERSION == 2
%<#endif
" \
             --new-group-format="#if MAJOR_VERSION == 4
%>#endif
"       $0 $1 > $2 || true;
        rm $0 $1'

# merge the X.0 Android.bp & OWNERS in the all-versions
for dir in common effect core; do
    for sub in default vts/functional; do
        test -f $dir/2.0/$sub/Android.bp || continue
        awk 1 $dir/*.0/$sub/Android.bp >> $dir/all-versions/$sub/Android.bp
        # delete licenses except for the first one and add whitelines
        sed -i -e '/^}$/{N;/^}\n$/!s/\n/&\n/}' $dir/all-versions/$sub/Android.bp
        sed -i -e '1,17b;/^\/\//,/^$/{d}' $dir/all-versions/$sub/Android.bp
    done
    for sub in default vts; do
        test -d $dir/2.0/$sub || continue
        test -f $dir/2.0/$sub/OWNERS &&
            awk 1 $dir/*.0/$sub/OWNERS | sort -u > $dir/all-versions/$sub/OWNERS ||
            true
        rm -r $dir/*.0/$sub
    done
done

# delete all-versions-impl dependencies
find -name 'Android.bp' | xargs sed -i -e '/all-versions-impl/d'

# cleanup unused files
rm common/all-versions/default/include/common/all-versions/default/HidlUtils*
rm common/all-versions/util/include/common/all-versions/IncludeGuard.h
find -depth -type d -empty -delete

# Clamp consecutive number of empty lines to 2
find -name *.cpp -o -name *h | xargs sed -Ei ':a;/^\n*$/{N;ba};s/\n\n+/\n\n/'

# transform #endif\n#if to #elif
find -name *.cpp -o -name *h | xargs sed -i '/^#endif/{N;s/.*\n#if/#elif/}'

# remove leftover include guard in cpp
find -name *.cpp |xargs sed -Ei '/^#.*_H_?$/d'

# apply clang-format
find -name *cpp -o -name *h |
    xargs ../../../prebuilts/clang/host/linux-x86/clang-stable/bin/clang-format --style file -i
# clang format breaks PATH(a/b) to PATH(a / b), remove the space surrounding /
find -name *cpp -o -name *h | xargs sed -i "/#include PATH/s# / #/#g"

Test: compile
Bug: 118203066
Change-Id: I3692a444307afc5f71064fe0b9e6b8af3c9ff1dd
Signed-off-by: Kevin Rocard <krocard@google.com>

1 files changed, 580 insertions, 0 deletions

diff --git a/audio/core/all-versions/default/StreamOut.cpp b/audio/core/all-versions/default/StreamOut.cpp
new file mode 100644
index 0000000000..4ae0fb19c1
--- /dev/null
+++ b/audio/core/all-versions/default/StreamOut.cpp
@@ -0,0 +1,580 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "StreamOutHAL"
+
+#include "core/default/StreamOut.h"
+#include "core/default/Util.h"
+
+//#define LOG_NDEBUG 0
+#define ATRACE_TAG ATRACE_TAG_AUDIO
+
+#include <memory>
+
+#include <android/log.h>
+#include <hardware/audio.h>
+#include <utils/Trace.h>
+
+namespace android {
+namespace hardware {
+namespace audio {
+namespace CPP_VERSION {
+namespace implementation {
+
+using ::android::hardware::audio::common::CPP_VERSION::ThreadInfo;
+
+namespace {
+
+class WriteThread : public Thread {
+   public:
+    // WriteThread's lifespan never exceeds StreamOut's lifespan.
+    WriteThread(std::atomic<bool>* stop, audio_stream_out_t* stream,
+                StreamOut::CommandMQ* commandMQ, StreamOut::DataMQ* dataMQ,
+                StreamOut::StatusMQ* statusMQ, EventFlag* efGroup)
+        : Thread(false /*canCallJava*/),
+          mStop(stop),
+          mStream(stream),
+          mCommandMQ(commandMQ),
+          mDataMQ(dataMQ),
+          mStatusMQ(statusMQ),
+          mEfGroup(efGroup),
+          mBuffer(nullptr) {}
+    bool init() {
+        mBuffer.reset(new (std::nothrow) uint8_t[mDataMQ->getQuantumCount()]);
+        return mBuffer != nullptr;
+    }
+    virtual ~WriteThread() {}
+
+   private:
+    std::atomic<bool>* mStop;
+    audio_stream_out_t* mStream;
+    StreamOut::CommandMQ* mCommandMQ;
+    StreamOut::DataMQ* mDataMQ;
+    StreamOut::StatusMQ* mStatusMQ;
+    EventFlag* mEfGroup;
+    std::unique_ptr<uint8_t[]> mBuffer;
+    IStreamOut::WriteStatus mStatus;
+
+    bool threadLoop() override;
+
+    void doGetLatency();
+    void doGetPresentationPosition();
+    void doWrite();
+};
+
+void WriteThread::doWrite() {
+    const size_t availToRead = mDataMQ->availableToRead();
+    mStatus.retval = Result::OK;
+    mStatus.reply.written = 0;
+    if (mDataMQ->read(&mBuffer[0], availToRead)) {
+        ssize_t writeResult = mStream->write(mStream, &mBuffer[0], availToRead);
+        if (writeResult >= 0) {
+            mStatus.reply.written = writeResult;
+        } else {
+            mStatus.retval = Stream::analyzeStatus("write", writeResult);
+        }
+    }
+}
+
+void WriteThread::doGetPresentationPosition() {
+    mStatus.retval =
+        StreamOut::getPresentationPositionImpl(mStream, &mStatus.reply.presentationPosition.frames,
+                                               &mStatus.reply.presentationPosition.timeStamp);
+}
+
+void WriteThread::doGetLatency() {
+    mStatus.retval = Result::OK;
+    mStatus.reply.latencyMs = mStream->get_latency(mStream);
+}
+
+bool WriteThread::threadLoop() {
+    // This implementation doesn't return control back to the Thread until it
+    // decides to stop,
+    // as the Thread uses mutexes, and this can lead to priority inversion.
+    while (!std::atomic_load_explicit(mStop, std::memory_order_acquire)) {
+        uint32_t efState = 0;
+        mEfGroup->wait(static_cast<uint32_t>(MessageQueueFlagBits::NOT_EMPTY), &efState);
+        if (!(efState & static_cast<uint32_t>(MessageQueueFlagBits::NOT_EMPTY))) {
+            continue;  // Nothing to do.
+        }
+        if (!mCommandMQ->read(&mStatus.replyTo)) {
+            continue;  // Nothing to do.
+        }
+        switch (mStatus.replyTo) {
+            case IStreamOut::WriteCommand::WRITE:
+                doWrite();
+                break;
+            case IStreamOut::WriteCommand::GET_PRESENTATION_POSITION:
+                doGetPresentationPosition();
+                break;
+            case IStreamOut::WriteCommand::GET_LATENCY:
+                doGetLatency();
+                break;
+            default:
+                ALOGE("Unknown write thread command code %d", mStatus.replyTo);
+                mStatus.retval = Result::NOT_SUPPORTED;
+                break;
+        }
+        if (!mStatusMQ->write(&mStatus)) {
+            ALOGE("status message queue write failed");
+        }
+        mEfGroup->wake(static_cast<uint32_t>(MessageQueueFlagBits::NOT_FULL));
+    }
+
+    return false;
+}
+
+}  // namespace
+
+StreamOut::StreamOut(const sp<Device>& device, audio_stream_out_t* stream)
+    : mIsClosed(false),
+      mDevice(device),
+      mStream(stream),
+      mStreamCommon(new Stream(&stream->common)),
+      mStreamMmap(new StreamMmap<audio_stream_out_t>(stream)),
+      mEfGroup(nullptr),
+      mStopWriteThread(false) {}
+
+StreamOut::~StreamOut() {
+    ATRACE_CALL();
+    close();
+    if (mWriteThread.get()) {
+        ATRACE_NAME("mWriteThread->join");
+        status_t status = mWriteThread->join();
+        ALOGE_IF(status, "write thread exit error: %s", strerror(-status));
+    }
+    if (mEfGroup) {
+        status_t status = EventFlag::deleteEventFlag(&mEfGroup);
+        ALOGE_IF(status, "write MQ event flag deletion error: %s", strerror(-status));
+    }
+    mCallback.clear();
+    mDevice->closeOutputStream(mStream);
+    // Closing the output stream in the HAL waits for the callback to finish,
+    // and joins the callback thread. Thus is it guaranteed that the callback
+    // thread will not be accessing our object anymore.
+    mStream = nullptr;
+}
+
+// Methods from ::android::hardware::audio::CPP_VERSION::IStream follow.
+Return<uint64_t> StreamOut::getFrameSize() {
+    return audio_stream_out_frame_size(mStream);
+}
+
+Return<uint64_t> StreamOut::getFrameCount() {
+    return mStreamCommon->getFrameCount();
+}
+
+Return<uint64_t> StreamOut::getBufferSize() {
+    return mStreamCommon->getBufferSize();
+}
+
+Return<uint32_t> StreamOut::getSampleRate() {
+    return mStreamCommon->getSampleRate();
+}
+
+#if MAJOR_VERSION == 2
+Return<void> StreamOut::getSupportedChannelMasks(getSupportedChannelMasks_cb _hidl_cb) {
+    return mStreamCommon->getSupportedChannelMasks(_hidl_cb);
+}
+Return<void> StreamOut::getSupportedSampleRates(getSupportedSampleRates_cb _hidl_cb) {
+    return mStreamCommon->getSupportedSampleRates(_hidl_cb);
+}
+#endif
+
+Return<void> StreamOut::getSupportedChannelMasks(AudioFormat format,
+                                                 getSupportedChannelMasks_cb _hidl_cb) {
+    return mStreamCommon->getSupportedChannelMasks(format, _hidl_cb);
+}
+Return<void> StreamOut::getSupportedSampleRates(AudioFormat format,
+                                                getSupportedSampleRates_cb _hidl_cb) {
+    return mStreamCommon->getSupportedSampleRates(format, _hidl_cb);
+}
+
+Return<Result> StreamOut::setSampleRate(uint32_t sampleRateHz) {
+    return mStreamCommon->setSampleRate(sampleRateHz);
+}
+
+Return<AudioChannelBitfield> StreamOut::getChannelMask() {
+    return mStreamCommon->getChannelMask();
+}
+
+Return<Result> StreamOut::setChannelMask(AudioChannelBitfield mask) {
+    return mStreamCommon->setChannelMask(mask);
+}
+
+Return<AudioFormat> StreamOut::getFormat() {
+    return mStreamCommon->getFormat();
+}
+
+Return<void> StreamOut::getSupportedFormats(getSupportedFormats_cb _hidl_cb) {
+    return mStreamCommon->getSupportedFormats(_hidl_cb);
+}
+
+Return<Result> StreamOut::setFormat(AudioFormat format) {
+    return mStreamCommon->setFormat(format);
+}
+
+Return<void> StreamOut::getAudioProperties(getAudioProperties_cb _hidl_cb) {
+    return mStreamCommon->getAudioProperties(_hidl_cb);
+}
+
+Return<Result> StreamOut::addEffect(uint64_t effectId) {
+    return mStreamCommon->addEffect(effectId);
+}
+
+Return<Result> StreamOut::removeEffect(uint64_t effectId) {
+    return mStreamCommon->removeEffect(effectId);
+}
+
+Return<Result> StreamOut::standby() {
+    return mStreamCommon->standby();
+}
+
+Return<Result> StreamOut::setHwAvSync(uint32_t hwAvSync) {
+    return mStreamCommon->setHwAvSync(hwAvSync);
+}
+
+#if MAJOR_VERSION == 2
+Return<Result> StreamOut::setConnectedState(const DeviceAddress& address, bool connected) {
+    return mStreamCommon->setConnectedState(address, connected);
+}
+
+Return<AudioDevice> StreamOut::getDevice() {
+    return mStreamCommon->getDevice();
+}
+
+Return<Result> StreamOut::setDevice(const DeviceAddress& address) {
+    return mStreamCommon->setDevice(address);
+}
+
+Return<void> StreamOut::getParameters(const hidl_vec<hidl_string>& keys,
+                                      getParameters_cb _hidl_cb) {
+    return mStreamCommon->getParameters(keys, _hidl_cb);
+}
+
+Return<Result> StreamOut::setParameters(const hidl_vec<ParameterValue>& parameters) {
+    return mStreamCommon->setParameters(parameters);
+}
+
+Return<void> StreamOut::debugDump(const hidl_handle& fd) {
+    return mStreamCommon->debugDump(fd);
+}
+#elif MAJOR_VERSION == 4
+Return<void> StreamOut::getDevices(getDevices_cb _hidl_cb) {
+    return mStreamCommon->getDevices(_hidl_cb);
+}
+
+Return<Result> StreamOut::setDevices(const hidl_vec<DeviceAddress>& devices) {
+    return mStreamCommon->setDevices(devices);
+}
+Return<void> StreamOut::getParameters(const hidl_vec<ParameterValue>& context,
+                                      const hidl_vec<hidl_string>& keys,
+                                      getParameters_cb _hidl_cb) {
+    return mStreamCommon->getParameters(context, keys, _hidl_cb);
+}
+
+Return<Result> StreamOut::setParameters(const hidl_vec<ParameterValue>& context,
+                                        const hidl_vec<ParameterValue>& parameters) {
+    return mStreamCommon->setParameters(context, parameters);
+}
+#endif
+
+Return<Result> StreamOut::close() {
+    if (mIsClosed) return Result::INVALID_STATE;
+    mIsClosed = true;
+    if (mWriteThread.get()) {
+        mStopWriteThread.store(true, std::memory_order_release);
+    }
+    if (mEfGroup) {
+        mEfGroup->wake(static_cast<uint32_t>(MessageQueueFlagBits::NOT_EMPTY));
+    }
+    return Result::OK;
+}
+
+// Methods from ::android::hardware::audio::CPP_VERSION::IStreamOut follow.
+Return<uint32_t> StreamOut::getLatency() {
+    return mStream->get_latency(mStream);
+}
+
+Return<Result> StreamOut::setVolume(float left, float right) {
+    if (mStream->set_volume == NULL) {
+        return Result::NOT_SUPPORTED;
+    }
+    if (!isGainNormalized(left)) {
+        ALOGW("Can not set a stream output volume {%f, %f} outside [0,1]", left, right);
+        return Result::INVALID_ARGUMENTS;
+    }
+    return Stream::analyzeStatus("set_volume", mStream->set_volume(mStream, left, right));
+}
+
+Return<void> StreamOut::prepareForWriting(uint32_t frameSize, uint32_t framesCount,
+                                          prepareForWriting_cb _hidl_cb) {
+    status_t status;
+    ThreadInfo threadInfo = {0, 0};
+
+    // Wrap the _hidl_cb to return an error
+    auto sendError = [&threadInfo, &_hidl_cb](Result result) {
+        _hidl_cb(result, CommandMQ::Descriptor(), DataMQ::Descriptor(), StatusMQ::Descriptor(),
+                 threadInfo);
+    };
+
+    // Create message queues.
+    if (mDataMQ) {
+        ALOGE("the client attempts to call prepareForWriting twice");
+        sendError(Result::INVALID_STATE);
+        return Void();
+    }
+    std::unique_ptr<CommandMQ> tempCommandMQ(new CommandMQ(1));
+
+    // Check frameSize and framesCount
+    if (frameSize == 0 || framesCount == 0) {
+        ALOGE("Null frameSize (%u) or framesCount (%u)", frameSize, framesCount);
+        sendError(Result::INVALID_ARGUMENTS);
+        return Void();
+    }
+    if (frameSize > Stream::MAX_BUFFER_SIZE / framesCount) {
+        ALOGE("Buffer too big: %u*%u bytes > MAX_BUFFER_SIZE (%u)", frameSize, framesCount,
+              Stream::MAX_BUFFER_SIZE);
+        sendError(Result::INVALID_ARGUMENTS);
+        return Void();
+    }
+    std::unique_ptr<DataMQ> tempDataMQ(new DataMQ(frameSize * framesCount, true /* EventFlag */));
+
+    std::unique_ptr<StatusMQ> tempStatusMQ(new StatusMQ(1));
+    if (!tempCommandMQ->isValid() || !tempDataMQ->isValid() || !tempStatusMQ->isValid()) {
+        ALOGE_IF(!tempCommandMQ->isValid(), "command MQ is invalid");
+        ALOGE_IF(!tempDataMQ->isValid(), "data MQ is invalid");
+        ALOGE_IF(!tempStatusMQ->isValid(), "status MQ is invalid");
+        sendError(Result::INVALID_ARGUMENTS);
+        return Void();
+    }
+    EventFlag* tempRawEfGroup{};
+    status = EventFlag::createEventFlag(tempDataMQ->getEventFlagWord(), &tempRawEfGroup);
+    std::unique_ptr<EventFlag, void (*)(EventFlag*)> tempElfGroup(
+        tempRawEfGroup, [](auto* ef) { EventFlag::deleteEventFlag(&ef); });
+    if (status != OK || !tempElfGroup) {
+        ALOGE("failed creating event flag for data MQ: %s", strerror(-status));
+        sendError(Result::INVALID_ARGUMENTS);
+        return Void();
+    }
+
+    // Create and launch the thread.
+    auto tempWriteThread =
+        std::make_unique<WriteThread>(&mStopWriteThread, mStream, tempCommandMQ.get(),
+                                      tempDataMQ.get(), tempStatusMQ.get(), tempElfGroup.get());
+    if (!tempWriteThread->init()) {
+        ALOGW("failed to start writer thread: %s", strerror(-status));
+        sendError(Result::INVALID_ARGUMENTS);
+        return Void();
+    }
+    status = tempWriteThread->run("writer", PRIORITY_URGENT_AUDIO);
+    if (status != OK) {
+        ALOGW("failed to start writer thread: %s", strerror(-status));
+        sendError(Result::INVALID_ARGUMENTS);
+        return Void();
+    }
+
+    mCommandMQ = std::move(tempCommandMQ);
+    mDataMQ = std::move(tempDataMQ);
+    mStatusMQ = std::move(tempStatusMQ);
+    mWriteThread = tempWriteThread.release();
+    mEfGroup = tempElfGroup.release();
+    threadInfo.pid = getpid();
+    threadInfo.tid = mWriteThread->getTid();
+    _hidl_cb(Result::OK, *mCommandMQ->getDesc(), *mDataMQ->getDesc(), *mStatusMQ->getDesc(),
+             threadInfo);
+    return Void();
+}
+
+Return<void> StreamOut::getRenderPosition(getRenderPosition_cb _hidl_cb) {
+    uint32_t halDspFrames;
+    Result retval = Stream::analyzeStatus("get_render_position",
+                                          mStream->get_render_position(mStream, &halDspFrames));
+    _hidl_cb(retval, halDspFrames);
+    return Void();
+}
+
+Return<void> StreamOut::getNextWriteTimestamp(getNextWriteTimestamp_cb _hidl_cb) {
+    Result retval(Result::NOT_SUPPORTED);
+    int64_t timestampUs = 0;
+    if (mStream->get_next_write_timestamp != NULL) {
+        retval = Stream::analyzeStatus("get_next_write_timestamp",
+                                       mStream->get_next_write_timestamp(mStream, &timestampUs));
+    }
+    _hidl_cb(retval, timestampUs);
+    return Void();
+}
+
+Return<Result> StreamOut::setCallback(const sp<IStreamOutCallback>& callback) {
+    if (mStream->set_callback == NULL) return Result::NOT_SUPPORTED;
+    // Safe to pass 'this' because it is guaranteed that the callback thread
+    // is joined prior to exit from StreamOut's destructor.
+    int result = mStream->set_callback(mStream, StreamOut::asyncCallback, this);
+    if (result == 0) {
+        mCallback = callback;
+    }
+    return Stream::analyzeStatus("set_callback", result);
+}
+
+Return<Result> StreamOut::clearCallback() {
+    if (mStream->set_callback == NULL) return Result::NOT_SUPPORTED;
+    mCallback.clear();
+    return Result::OK;
+}
+
+// static
+int StreamOut::asyncCallback(stream_callback_event_t event, void*, void* cookie) {
+    // It is guaranteed that the callback thread is joined prior
+    // to exiting from StreamOut's destructor. Must *not* use sp<StreamOut>
+    // here because it can make this code the last owner of StreamOut,
+    // and an attempt to run the destructor on the callback thread
+    // will cause a deadlock in the legacy HAL code.
+    StreamOut* self = reinterpret_cast<StreamOut*>(cookie);
+    // It's correct to hold an sp<> to callback because the reference
+    // in the StreamOut instance can be cleared in the meantime. There is
+    // no difference on which thread to run IStreamOutCallback's destructor.
+    sp<IStreamOutCallback> callback = self->mCallback;
+    if (callback.get() == nullptr) return 0;
+    ALOGV("asyncCallback() event %d", event);
+    switch (event) {
+        case STREAM_CBK_EVENT_WRITE_READY:
+            callback->onWriteReady();
+            break;
+        case STREAM_CBK_EVENT_DRAIN_READY:
+            callback->onDrainReady();
+            break;
+        case STREAM_CBK_EVENT_ERROR:
+            callback->onError();
+            break;
+        default:
+            ALOGW("asyncCallback() unknown event %d", event);
+            break;
+    }
+    return 0;
+}
+
+Return<void> StreamOut::supportsPauseAndResume(supportsPauseAndResume_cb _hidl_cb) {
+    _hidl_cb(mStream->pause != NULL, mStream->resume != NULL);
+    return Void();
+}
+
+Return<Result> StreamOut::pause() {
+    return mStream->pause != NULL ? Stream::analyzeStatus("pause", mStream->pause(mStream))
+                                  : Result::NOT_SUPPORTED;
+}
+
+Return<Result> StreamOut::resume() {
+    return mStream->resume != NULL ? Stream::analyzeStatus("resume", mStream->resume(mStream))
+                                   : Result::NOT_SUPPORTED;
+}
+
+Return<bool> StreamOut::supportsDrain() {
+    return mStream->drain != NULL;
+}
+
+Return<Result> StreamOut::drain(AudioDrain type) {
+    return mStream->drain != NULL
+               ? Stream::analyzeStatus(
+                     "drain", mStream->drain(mStream, static_cast<audio_drain_type_t>(type)))
+               : Result::NOT_SUPPORTED;
+}
+
+Return<Result> StreamOut::flush() {
+    return mStream->flush != NULL ? Stream::analyzeStatus("flush", mStream->flush(mStream))
+                                  : Result::NOT_SUPPORTED;
+}
+
+// static
+Result StreamOut::getPresentationPositionImpl(audio_stream_out_t* stream, uint64_t* frames,
+                                              TimeSpec* timeStamp) {
+    // Don't logspam on EINVAL--it's normal for get_presentation_position
+    // to return it sometimes. EAGAIN may be returned by A2DP audio HAL
+    // implementation. ENODATA can also be reported while the writer is
+    // continuously querying it, but the stream has been stopped.
+    static const std::vector<int> ignoredErrors{EINVAL, EAGAIN, ENODATA};
+    Result retval(Result::NOT_SUPPORTED);
+    if (stream->get_presentation_position == NULL) return retval;
+    struct timespec halTimeStamp;
+    retval = Stream::analyzeStatus("get_presentation_position",
+                                   stream->get_presentation_position(stream, frames, &halTimeStamp),
+                                   ignoredErrors);
+    if (retval == Result::OK) {
+        timeStamp->tvSec = halTimeStamp.tv_sec;
+        timeStamp->tvNSec = halTimeStamp.tv_nsec;
+    }
+    return retval;
+}
+
+Return<void> StreamOut::getPresentationPosition(getPresentationPosition_cb _hidl_cb) {
+    uint64_t frames = 0;
+    TimeSpec timeStamp = {0, 0};
+    Result retval = getPresentationPositionImpl(mStream, &frames, &timeStamp);
+    _hidl_cb(retval, frames, timeStamp);
+    return Void();
+}
+
+Return<Result> StreamOut::start() {
+    return mStreamMmap->start();
+}
+
+Return<Result> StreamOut::stop() {
+    return mStreamMmap->stop();
+}
+
+Return<void> StreamOut::createMmapBuffer(int32_t minSizeFrames, createMmapBuffer_cb _hidl_cb) {
+    return mStreamMmap->createMmapBuffer(minSizeFrames, audio_stream_out_frame_size(mStream),
+                                         _hidl_cb);
+}
+
+Return<void> StreamOut::getMmapPosition(getMmapPosition_cb _hidl_cb) {
+    return mStreamMmap->getMmapPosition(_hidl_cb);
+}
+
+Return<void> StreamOut::debug(const hidl_handle& fd, const hidl_vec<hidl_string>& options) {
+    return mStreamCommon->debug(fd, options);
+}
+
+#if MAJOR_VERSION == 4
+Return<void> StreamOut::updateSourceMetadata(const SourceMetadata& sourceMetadata) {
+    if (mStream->update_source_metadata == nullptr) {
+        return Void();  // not supported by the HAL
+    }
+    std::vector<playback_track_metadata> halTracks;
+    halTracks.reserve(sourceMetadata.tracks.size());
+    for (auto& metadata : sourceMetadata.tracks) {
+        halTracks.push_back({
+            .usage = static_cast<audio_usage_t>(metadata.usage),
+            .content_type = static_cast<audio_content_type_t>(metadata.contentType),
+            .gain = metadata.gain,
+        });
+    }
+    const source_metadata_t halMetadata = {
+        .track_count = halTracks.size(),
+        .tracks = halTracks.data(),
+    };
+    mStream->update_source_metadata(mStream, &halMetadata);
+    return Void();
+}
+Return<Result> StreamOut::selectPresentation(int32_t /*presentationId*/, int32_t /*programId*/) {
+    return Result::NOT_SUPPORTED;  // TODO: propagate to legacy
+}
+#endif
+
+}  // namespace implementation
+}  // namespace CPP_VERSION
+}  // namespace audio
+}  // namespace hardware
+}  // namespace android