media/codec2/hidl/1.0/utils/InputBufferManager.cpp - LeafOS-Project/android_frameworks_av - Gitiles

 /*
  * Copyright 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_NDEBUG 0
 #define LOG_TAG "Codec2-InputBufferManager"
 #include <android-base/logging.h>

 #include <codec2/hidl/1.0/InputBufferManager.h>
 #include <codec2/hidl/1.0/types.h>

 #include <android/hardware/media/c2/1.0/IComponentListener.h>
 #include <android-base/logging.h>

 #include <C2Buffer.h>
 #include <C2Work.h>

 #include <chrono>

 namespace android {
 namespace hardware {
 namespace media {
 namespace c2 {
 namespace V1_0 {
 namespace utils {

 using namespace ::android;

 void InputBufferManager::registerFrameData(
         const sp<IComponentListener>& listener,
         const C2FrameData& input) {
     getInstance()._registerFrameData(listener, input);
 }

 void InputBufferManager::unregisterFrameData(
         const wp<IComponentListener>& listener,
         const C2FrameData& input) {
     getInstance()._unregisterFrameData(listener, input);
 }

 void InputBufferManager::unregisterFrameData(
         const wp<IComponentListener>& listener) {
     getInstance()._unregisterFrameData(listener);
 }

 void InputBufferManager::setNotificationInterval(
         nsecs_t notificationIntervalNs) {
     getInstance()._setNotificationInterval(notificationIntervalNs);
 }

 void InputBufferManager::_registerFrameData(
         const sp<IComponentListener>& listener,
         const C2FrameData& input) {
     uint64_t frameIndex = input.ordinal.frameIndex.peeku();
     LOG(VERBOSE) << "InputBufferManager::_registerFrameData -- called with "
                  << "listener @ 0x" << std::hex << listener.get()
                  << ", frameIndex = " << std::dec << frameIndex
                  << ".";
     std::lock_guard<std::mutex> lock(mMutex);

     std::set<TrackedBuffer> &bufferIds =
             mTrackedBuffersMap[listener][frameIndex];

     for (size_t i = 0; i < input.buffers.size(); ++i) {
         if (!input.buffers[i]) {
             LOG(VERBOSE) << "InputBufferManager::_registerFrameData -- "
                          << "Input buffer at index " << i << " is null.";
             continue;
         }
         const TrackedBuffer &bufferId =
                 *bufferIds.emplace(listener, frameIndex, i, input.buffers[i]).
                 first;

         c2_status_t status = input.buffers[i]->registerOnDestroyNotify(
                 onBufferDestroyed,
                 const_cast<void*>(reinterpret_cast<const void*>(&bufferId)));
         if (status != C2_OK) {
             LOG(DEBUG) << "InputBufferManager::_registerFrameData -- "
                        << "registerOnDestroyNotify() failed "
                        << "(listener @ 0x" << std::hex << listener.get()
                        << ", frameIndex = " << std::dec << frameIndex
                        << ", bufferIndex = " << i
                        << ") => status = " << status
                        << ".";
         }
     }

     mDeathNotifications.emplace(
             listener,
             DeathNotifications(
                 mNotificationIntervalNs.load(std::memory_order_relaxed)));
 }

 // Remove a pair (listener, frameIndex) from mTrackedBuffersMap and
 // mDeathNotifications. This implies all bufferIndices are removed.
 //
 // This is called from onWorkDone() and flush().
 void InputBufferManager::_unregisterFrameData(
         const wp<IComponentListener>& listener,
         const C2FrameData& input) {
     uint64_t frameIndex = input.ordinal.frameIndex.peeku();
     LOG(VERBOSE) << "InputBufferManager::_unregisterFrameData -- called with "
                  << "listener @ 0x" << std::hex << listener.unsafe_get()
                  << ", frameIndex = " << std::dec << frameIndex
                  << ".";
     std::lock_guard<std::mutex> lock(mMutex);

     auto findListener = mTrackedBuffersMap.find(listener);
     if (findListener != mTrackedBuffersMap.end()) {
         std::map<uint64_t, std::set<TrackedBuffer>> &frameIndex2BufferIds
                 = findListener->second;
         auto findFrameIndex = frameIndex2BufferIds.find(frameIndex);
         if (findFrameIndex != frameIndex2BufferIds.end()) {
             std::set<TrackedBuffer> &bufferIds = findFrameIndex->second;
             for (const TrackedBuffer& bufferId : bufferIds) {
                 std::shared_ptr<C2Buffer> buffer = bufferId.buffer.lock();
                 if (buffer) {
                     c2_status_t status = buffer->unregisterOnDestroyNotify(
                             onBufferDestroyed,
                             const_cast<void*>(
                             reinterpret_cast<const void*>(&bufferId)));
                     if (status != C2_OK) {
                         LOG(DEBUG) << "InputBufferManager::_unregisterFrameData "
                                    << "-- unregisterOnDestroyNotify() failed "
                                    << "(listener @ 0x"
                                         << std::hex
                                         << bufferId.listener.unsafe_get()
                                    << ", frameIndex = "
                                         << std::dec << bufferId.frameIndex
                                    << ", bufferIndex = " << bufferId.bufferIndex
                                    << ") => status = " << status
                                    << ".";
                     }
                 }
             }

             frameIndex2BufferIds.erase(findFrameIndex);
             if (frameIndex2BufferIds.empty()) {
                 mTrackedBuffersMap.erase(findListener);
             }
         }
     }

     auto findListenerD = mDeathNotifications.find(listener);
     if (findListenerD != mDeathNotifications.end()) {
         DeathNotifications &deathNotifications = findListenerD->second;
         auto findFrameIndex = deathNotifications.indices.find(frameIndex);
         if (findFrameIndex != deathNotifications.indices.end()) {
             std::vector<size_t> &bufferIndices = findFrameIndex->second;
             deathNotifications.count -= bufferIndices.size();
             deathNotifications.indices.erase(findFrameIndex);
         }
     }
 }

 // Remove listener from mTrackedBuffersMap and mDeathNotifications. This implies
 // all frameIndices and bufferIndices are removed.
 //
 // This is called when the component cleans up all input buffers, i.e., when
 // reset(), release(), stop() or ~Component() is called.
 void InputBufferManager::_unregisterFrameData(
         const wp<IComponentListener>& listener) {
     LOG(VERBOSE) << "InputBufferManager::_unregisterFrameData -- called with "
                  << "listener @ 0x" << std::hex << listener.unsafe_get()
                  << std::dec << ".";
     std::lock_guard<std::mutex> lock(mMutex);

     auto findListener = mTrackedBuffersMap.find(listener);
     if (findListener != mTrackedBuffersMap.end()) {
         std::map<uint64_t, std::set<TrackedBuffer>> &frameIndex2BufferIds =
                 findListener->second;
         for (auto findFrameIndex = frameIndex2BufferIds.begin();
                 findFrameIndex != frameIndex2BufferIds.end();
                 ++findFrameIndex) {
             std::set<TrackedBuffer> &bufferIds = findFrameIndex->second;
             for (const TrackedBuffer& bufferId : bufferIds) {
                 std::shared_ptr<C2Buffer> buffer = bufferId.buffer.lock();
                 if (buffer) {
                     c2_status_t status = buffer->unregisterOnDestroyNotify(
                             onBufferDestroyed,
                             const_cast<void*>(
                             reinterpret_cast<const void*>(&bufferId)));
                     if (status != C2_OK) {
                         LOG(DEBUG) << "InputBufferManager::_unregisterFrameData "
                                    << "-- unregisterOnDestroyNotify() failed "
                                    << "(listener @ 0x"
                                         << std::hex
                                         << bufferId.listener.unsafe_get()
                                    << ", frameIndex = "
                                         << std::dec << bufferId.frameIndex
                                    << ", bufferIndex = " << bufferId.bufferIndex
                                    << ") => status = " << status
                                    << ".";
                     }
                 }
             }
         }
         mTrackedBuffersMap.erase(findListener);
     }

     mDeathNotifications.erase(listener);
 }

 // Set mNotificationIntervalNs.
 void InputBufferManager::_setNotificationInterval(
         nsecs_t notificationIntervalNs) {
     mNotificationIntervalNs.store(
             notificationIntervalNs,
             std::memory_order_relaxed);
 }

 // Move a buffer from mTrackedBuffersMap to mDeathNotifications.
 // This is called when a registered C2Buffer object is destroyed.
 void InputBufferManager::onBufferDestroyed(const C2Buffer* buf, void* arg) {
     getInstance()._onBufferDestroyed(buf, arg);
 }

 void InputBufferManager::_onBufferDestroyed(const C2Buffer* buf, void* arg) {
     if (!buf || !arg) {
         LOG(WARNING) << "InputBufferManager::_onBufferDestroyed -- called with "
                      << "null argument (s): "
                      << "buf @ 0x" << std::hex << buf
                      << ", arg @ 0x" << std::hex << arg
                      << std::dec << ".";
         return;
     }
     TrackedBuffer id(*reinterpret_cast<TrackedBuffer*>(arg));
     LOG(VERBOSE) << "InputBufferManager::_onBufferDestroyed -- called with "
                  << "buf @ 0x" << std::hex << buf
                  << ", arg @ 0x" << std::hex << arg
                  << std::dec << " -- "
                  << "listener @ 0x" << std::hex << id.listener.unsafe_get()
                  << ", frameIndex = " << std::dec << id.frameIndex
                  << ", bufferIndex = " << id.bufferIndex
                  << ".";

     std::lock_guard<std::mutex> lock(mMutex);

     auto findListener = mTrackedBuffersMap.find(id.listener);
     if (findListener == mTrackedBuffersMap.end()) {
         LOG(DEBUG) << "InputBufferManager::_onBufferDestroyed -- "
                    << "received invalid listener: "
                    << "listener @ 0x" << std::hex << id.listener.unsafe_get()
                    << " (frameIndex = " << std::dec << id.frameIndex
                    << ", bufferIndex = " << id.bufferIndex
                    << ").";
         return;
     }

     std::map<uint64_t, std::set<TrackedBuffer>> &frameIndex2BufferIds
             = findListener->second;
     auto findFrameIndex = frameIndex2BufferIds.find(id.frameIndex);
     if (findFrameIndex == frameIndex2BufferIds.end()) {
         LOG(DEBUG) << "InputBufferManager::_onBufferDestroyed -- "
                    << "received invalid frame index: "
                    << "frameIndex = " << id.frameIndex
                    << " (listener @ 0x" << std::hex << id.listener.unsafe_get()
                    << ", bufferIndex = " << std::dec << id.bufferIndex
                    << ").";
         return;
     }

     std::set<TrackedBuffer> &bufferIds = findFrameIndex->second;
     auto findBufferId = bufferIds.find(id);
     if (findBufferId == bufferIds.end()) {
         LOG(DEBUG) << "InputBufferManager::_onBufferDestroyed -- "
                    << "received invalid buffer index: "
                    << "bufferIndex = " << id.bufferIndex
                    << " (frameIndex = " << id.frameIndex
                    << ", listener @ 0x" << std::hex << id.listener.unsafe_get()
                    << std::dec << ").";
         return;
     }

     bufferIds.erase(findBufferId);
     if (bufferIds.empty()) {
         frameIndex2BufferIds.erase(findFrameIndex);
         if (frameIndex2BufferIds.empty()) {
             mTrackedBuffersMap.erase(findListener);
         }
     }

     DeathNotifications &deathNotifications = mDeathNotifications[id.listener];
     deathNotifications.indices[id.frameIndex].emplace_back(id.bufferIndex);
     ++deathNotifications.count;
     mOnBufferDestroyed.notify_one();
 }

 // Notify the clients about buffer destructions.
 // Return false if all destructions have been notified.
 // Return true and set timeToRetry to the time point to wait for before
 // retrying if some destructions have not been notified.
 bool InputBufferManager::processNotifications(nsecs_t* timeToRetryNs) {

     struct Notification {
         sp<IComponentListener> listener;
         hidl_vec<IComponentListener::InputBuffer> inputBuffers;
         Notification(const sp<IComponentListener>& l, size_t s)
               : listener(l), inputBuffers(s) {}
     };
     std::list<Notification> notifications;
     nsecs_t notificationIntervalNs =
             mNotificationIntervalNs.load(std::memory_order_relaxed);

     bool retry = false;
     {
         std::lock_guard<std::mutex> lock(mMutex);
         *timeToRetryNs = notificationIntervalNs;
         nsecs_t timeNowNs = systemTime();
         for (auto it = mDeathNotifications.begin();
                 it != mDeathNotifications.end(); ) {
             sp<IComponentListener> listener = it->first.promote();
             if (!listener) {
                 ++it;
                 continue;
             }
             DeathNotifications &deathNotifications = it->second;

             nsecs_t timeSinceLastNotifiedNs =
                     timeNowNs - deathNotifications.lastSentNs;
             // If not enough time has passed since the last callback, leave the
             // notifications for this listener untouched for now and retry
             // later.
             if (timeSinceLastNotifiedNs < notificationIntervalNs) {
                 retry = true;
                 *timeToRetryNs = std::min(*timeToRetryNs,
                         notificationIntervalNs - timeSinceLastNotifiedNs);
                 LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
                              << "Notifications for listener @ "
                                  << std::hex << listener.get()
                              << " will be postponed.";
                 ++it;
                 continue;
             }

             // If enough time has passed since the last notification to this
             // listener but there are currently no pending notifications, the
             // listener can be removed from mDeathNotifications---there is no
             // need to keep track of the last notification time anymore.
             if (deathNotifications.count == 0) {
                 it = mDeathNotifications.erase(it);
                 continue;
             }

             // Create the argument for the callback.
             notifications.emplace_back(listener, deathNotifications.count);
             hidl_vec<IComponentListener::InputBuffer> &inputBuffers =
                     notifications.back().inputBuffers;
             size_t i = 0;
             for (std::pair<const uint64_t, std::vector<size_t>>& p :
                     deathNotifications.indices) {
                 uint64_t frameIndex = p.first;
                 const std::vector<size_t> &bufferIndices = p.second;
                 for (const size_t& bufferIndex : bufferIndices) {
                     IComponentListener::InputBuffer &inputBuffer
                             = inputBuffers[i++];
                     inputBuffer.arrayIndex = bufferIndex;
                     inputBuffer.frameIndex = frameIndex;
                 }
             }

             // Clear deathNotifications for this listener and set retry to true
             // so processNotifications will be called again. This will
             // guarantee that a listener with no pending notifications will
             // eventually be removed from mDeathNotifications after
             // mNotificationIntervalNs nanoseconds has passed.
             retry = true;
             deathNotifications.indices.clear();
             deathNotifications.count = 0;
             deathNotifications.lastSentNs = timeNowNs;
             ++it;
         }
     }

     // Call onInputBuffersReleased() outside the lock to avoid deadlock.
     for (const Notification& notification : notifications) {
         if (!notification.listener->onInputBuffersReleased(
                 notification.inputBuffers).isOk()) {
             // This may trigger if the client has died.
             LOG(DEBUG) << "InputBufferManager::processNotifications -- "
                        << "failed to send death notifications to "
                        << "listener @ 0x" << std::hex
                                           << notification.listener.get()
                        << std::dec << ".";
         } else {
 #if LOG_NDEBUG == 0
             std::stringstream inputBufferLog;
             for (const IComponentListener::InputBuffer& inputBuffer :
                     notification.inputBuffers) {
                 inputBufferLog << " (" << inputBuffer.frameIndex
                                << ", " << inputBuffer.arrayIndex
                                << ")";
             }
             LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
                          << "death notifications sent to "
                          << "listener @ 0x" << std::hex
                                             << notification.listener.get()
                                             << std::dec
                          << " with these (frameIndex, bufferIndex) pairs:"
                          << inputBufferLog.str();
 #endif
         }
     }
 #if LOG_NDEBUG == 0
     if (retry) {
         LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
                      << "will retry again in " << *timeToRetryNs << "ns.";
     } else {
         LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
                      << "no pending death notifications.";
     }
 #endif
     return retry;
 }

 void InputBufferManager::main() {
     LOG(VERBOSE) << "InputBufferManager main -- started.";
     nsecs_t timeToRetryNs;
     while (true) {
         std::unique_lock<std::mutex> lock(mMutex);
         while (mDeathNotifications.empty()) {
             mOnBufferDestroyed.wait(lock);
         }
         lock.unlock();
         while (processNotifications(&timeToRetryNs)) {
             std::this_thread::sleep_for(
                     std::chrono::nanoseconds(timeToRetryNs));
         }
     }
 }

 InputBufferManager::InputBufferManager()
       : mMainThread{&InputBufferManager::main, this} {
 }

 InputBufferManager& InputBufferManager::getInstance() {
     static InputBufferManager instance{};
     return instance;
 }

 }  // namespace utils
 }  // namespace V1_0
 }  // namespace c2
 }  // namespace media
 }  // namespace hardware
 }  // namespace android
	/*
	* Copyright 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_NDEBUG 0
	#define LOG_TAG "Codec2-InputBufferManager"
	#include <android-base/logging.h>

	#include <codec2/hidl/1.0/InputBufferManager.h>
	#include <codec2/hidl/1.0/types.h>

	#include <android/hardware/media/c2/1.0/IComponentListener.h>
	#include <android-base/logging.h>

	#include <C2Buffer.h>
	#include <C2Work.h>

	#include <chrono>

	namespace android {
	namespace hardware {
	namespace media {
	namespace c2 {
	namespace V1_0 {
	namespace utils {

	using namespace ::android;

	void InputBufferManager::registerFrameData(
	const sp<IComponentListener>& listener,
	const C2FrameData& input) {
	getInstance()._registerFrameData(listener, input);
	}

	void InputBufferManager::unregisterFrameData(
	const wp<IComponentListener>& listener,
	const C2FrameData& input) {
	getInstance()._unregisterFrameData(listener, input);
	}

	void InputBufferManager::unregisterFrameData(
	const wp<IComponentListener>& listener) {
	getInstance()._unregisterFrameData(listener);
	}

	void InputBufferManager::setNotificationInterval(
	nsecs_t notificationIntervalNs) {
	getInstance()._setNotificationInterval(notificationIntervalNs);
	}

	void InputBufferManager::_registerFrameData(
	const sp<IComponentListener>& listener,
	const C2FrameData& input) {
	uint64_t frameIndex = input.ordinal.frameIndex.peeku();
	LOG(VERBOSE) << "InputBufferManager::_registerFrameData -- called with "
	<< "listener @ 0x" << std::hex << listener.get()
	<< ", frameIndex = " << std::dec << frameIndex
	<< ".";
	std::lock_guard<std::mutex> lock(mMutex);

	std::set<TrackedBuffer> &bufferIds =
	mTrackedBuffersMap[listener][frameIndex];

	for (size_t i = 0; i < input.buffers.size(); ++i) {
	if (!input.buffers[i]) {
	LOG(VERBOSE) << "InputBufferManager::_registerFrameData -- "
	<< "Input buffer at index " << i << " is null.";
	continue;
	}
	const TrackedBuffer &bufferId =
	*bufferIds.emplace(listener, frameIndex, i, input.buffers[i]).
	first;

	c2_status_t status = input.buffers[i]->registerOnDestroyNotify(
	onBufferDestroyed,
	const_cast<void>(reinterpret_cast<const void>(&bufferId)));
	if (status != C2_OK) {
	LOG(DEBUG) << "InputBufferManager::_registerFrameData -- "
	<< "registerOnDestroyNotify() failed "
	<< "(listener @ 0x" << std::hex << listener.get()
	<< ", frameIndex = " << std::dec << frameIndex
	<< ", bufferIndex = " << i
	<< ") => status = " << status
	<< ".";
	}
	}

	mDeathNotifications.emplace(
	listener,
	DeathNotifications(
	mNotificationIntervalNs.load(std::memory_order_relaxed)));
	}

	// Remove a pair (listener, frameIndex) from mTrackedBuffersMap and
	// mDeathNotifications. This implies all bufferIndices are removed.
	//
	// This is called from onWorkDone() and flush().
	void InputBufferManager::_unregisterFrameData(
	const wp<IComponentListener>& listener,
	const C2FrameData& input) {
	uint64_t frameIndex = input.ordinal.frameIndex.peeku();
	LOG(VERBOSE) << "InputBufferManager::_unregisterFrameData -- called with "
	<< "listener @ 0x" << std::hex << listener.unsafe_get()
	<< ", frameIndex = " << std::dec << frameIndex
	<< ".";
	std::lock_guard<std::mutex> lock(mMutex);

	auto findListener = mTrackedBuffersMap.find(listener);
	if (findListener != mTrackedBuffersMap.end()) {
	std::map<uint64_t, std::set<TrackedBuffer>> &frameIndex2BufferIds
	= findListener->second;
	auto findFrameIndex = frameIndex2BufferIds.find(frameIndex);
	if (findFrameIndex != frameIndex2BufferIds.end()) {
	std::set<TrackedBuffer> &bufferIds = findFrameIndex->second;
	for (const TrackedBuffer& bufferId : bufferIds) {
	std::shared_ptr<C2Buffer> buffer = bufferId.buffer.lock();
	if (buffer) {
	c2_status_t status = buffer->unregisterOnDestroyNotify(
	onBufferDestroyed,
	const_cast<void*>(
	reinterpret_cast<const void*>(&bufferId)));
	if (status != C2_OK) {
	LOG(DEBUG) << "InputBufferManager::_unregisterFrameData "
	<< "-- unregisterOnDestroyNotify() failed "
	<< "(listener @ 0x"
	<< std::hex
	<< bufferId.listener.unsafe_get()
	<< ", frameIndex = "
	<< std::dec << bufferId.frameIndex
	<< ", bufferIndex = " << bufferId.bufferIndex
	<< ") => status = " << status
	<< ".";
	}
	}
	}

	frameIndex2BufferIds.erase(findFrameIndex);
	if (frameIndex2BufferIds.empty()) {
	mTrackedBuffersMap.erase(findListener);
	}
	}
	}

	auto findListenerD = mDeathNotifications.find(listener);
	if (findListenerD != mDeathNotifications.end()) {
	DeathNotifications &deathNotifications = findListenerD->second;
	auto findFrameIndex = deathNotifications.indices.find(frameIndex);
	if (findFrameIndex != deathNotifications.indices.end()) {
	std::vector<size_t> &bufferIndices = findFrameIndex->second;
	deathNotifications.count -= bufferIndices.size();
	deathNotifications.indices.erase(findFrameIndex);
	}
	}
	}

	// Remove listener from mTrackedBuffersMap and mDeathNotifications. This implies
	// all frameIndices and bufferIndices are removed.
	//
	// This is called when the component cleans up all input buffers, i.e., when
	// reset(), release(), stop() or ~Component() is called.
	void InputBufferManager::_unregisterFrameData(
	const wp<IComponentListener>& listener) {
	LOG(VERBOSE) << "InputBufferManager::_unregisterFrameData -- called with "
	<< "listener @ 0x" << std::hex << listener.unsafe_get()
	<< std::dec << ".";
	std::lock_guard<std::mutex> lock(mMutex);

	auto findListener = mTrackedBuffersMap.find(listener);
	if (findListener != mTrackedBuffersMap.end()) {
	std::map<uint64_t, std::set<TrackedBuffer>> &frameIndex2BufferIds =
	findListener->second;
	for (auto findFrameIndex = frameIndex2BufferIds.begin();
	findFrameIndex != frameIndex2BufferIds.end();
	++findFrameIndex) {
	std::set<TrackedBuffer> &bufferIds = findFrameIndex->second;
	for (const TrackedBuffer& bufferId : bufferIds) {
	std::shared_ptr<C2Buffer> buffer = bufferId.buffer.lock();
	if (buffer) {
	c2_status_t status = buffer->unregisterOnDestroyNotify(
	onBufferDestroyed,
	const_cast<void*>(
	reinterpret_cast<const void*>(&bufferId)));
	if (status != C2_OK) {
	LOG(DEBUG) << "InputBufferManager::_unregisterFrameData "
	<< "-- unregisterOnDestroyNotify() failed "
	<< "(listener @ 0x"
	<< std::hex
	<< bufferId.listener.unsafe_get()
	<< ", frameIndex = "
	<< std::dec << bufferId.frameIndex
	<< ", bufferIndex = " << bufferId.bufferIndex
	<< ") => status = " << status
	<< ".";
	}
	}
	}
	}
	mTrackedBuffersMap.erase(findListener);
	}

	mDeathNotifications.erase(listener);
	}

	// Set mNotificationIntervalNs.
	void InputBufferManager::_setNotificationInterval(
	nsecs_t notificationIntervalNs) {
	mNotificationIntervalNs.store(
	notificationIntervalNs,
	std::memory_order_relaxed);
	}

	// Move a buffer from mTrackedBuffersMap to mDeathNotifications.
	// This is called when a registered C2Buffer object is destroyed.
	void InputBufferManager::onBufferDestroyed(const C2Buffer* buf, void* arg) {
	getInstance()._onBufferDestroyed(buf, arg);
	}

	void InputBufferManager::_onBufferDestroyed(const C2Buffer* buf, void* arg) {
	if (!buf \|\| !arg) {
	LOG(WARNING) << "InputBufferManager::_onBufferDestroyed -- called with "
	<< "null argument (s): "
	<< "buf @ 0x" << std::hex << buf
	<< ", arg @ 0x" << std::hex << arg
	<< std::dec << ".";
	return;
	}
	TrackedBuffer id(reinterpret_cast<TrackedBuffer>(arg));
	LOG(VERBOSE) << "InputBufferManager::_onBufferDestroyed -- called with "
	<< "buf @ 0x" << std::hex << buf
	<< ", arg @ 0x" << std::hex << arg
	<< std::dec << " -- "
	<< "listener @ 0x" << std::hex << id.listener.unsafe_get()
	<< ", frameIndex = " << std::dec << id.frameIndex
	<< ", bufferIndex = " << id.bufferIndex
	<< ".";

	std::lock_guard<std::mutex> lock(mMutex);

	auto findListener = mTrackedBuffersMap.find(id.listener);
	if (findListener == mTrackedBuffersMap.end()) {
	LOG(DEBUG) << "InputBufferManager::_onBufferDestroyed -- "
	<< "received invalid listener: "
	<< "listener @ 0x" << std::hex << id.listener.unsafe_get()
	<< " (frameIndex = " << std::dec << id.frameIndex
	<< ", bufferIndex = " << id.bufferIndex
	<< ").";
	return;
	}

	std::map<uint64_t, std::set<TrackedBuffer>> &frameIndex2BufferIds
	= findListener->second;
	auto findFrameIndex = frameIndex2BufferIds.find(id.frameIndex);
	if (findFrameIndex == frameIndex2BufferIds.end()) {
	LOG(DEBUG) << "InputBufferManager::_onBufferDestroyed -- "
	<< "received invalid frame index: "
	<< "frameIndex = " << id.frameIndex
	<< " (listener @ 0x" << std::hex << id.listener.unsafe_get()
	<< ", bufferIndex = " << std::dec << id.bufferIndex
	<< ").";
	return;
	}

	std::set<TrackedBuffer> &bufferIds = findFrameIndex->second;
	auto findBufferId = bufferIds.find(id);
	if (findBufferId == bufferIds.end()) {
	LOG(DEBUG) << "InputBufferManager::_onBufferDestroyed -- "
	<< "received invalid buffer index: "
	<< "bufferIndex = " << id.bufferIndex
	<< " (frameIndex = " << id.frameIndex
	<< ", listener @ 0x" << std::hex << id.listener.unsafe_get()
	<< std::dec << ").";
	return;
	}

	bufferIds.erase(findBufferId);
	if (bufferIds.empty()) {
	frameIndex2BufferIds.erase(findFrameIndex);
	if (frameIndex2BufferIds.empty()) {
	mTrackedBuffersMap.erase(findListener);
	}
	}

	DeathNotifications &deathNotifications = mDeathNotifications[id.listener];
	deathNotifications.indices[id.frameIndex].emplace_back(id.bufferIndex);
	++deathNotifications.count;
	mOnBufferDestroyed.notify_one();
	}

	// Notify the clients about buffer destructions.
	// Return false if all destructions have been notified.
	// Return true and set timeToRetry to the time point to wait for before
	// retrying if some destructions have not been notified.
	bool InputBufferManager::processNotifications(nsecs_t* timeToRetryNs) {

	struct Notification {
	sp<IComponentListener> listener;
	hidl_vec<IComponentListener::InputBuffer> inputBuffers;
	Notification(const sp<IComponentListener>& l, size_t s)
	: listener(l), inputBuffers(s) {}
	};
	std::list<Notification> notifications;
	nsecs_t notificationIntervalNs =
	mNotificationIntervalNs.load(std::memory_order_relaxed);

	bool retry = false;
	{
	std::lock_guard<std::mutex> lock(mMutex);
	*timeToRetryNs = notificationIntervalNs;
	nsecs_t timeNowNs = systemTime();
	for (auto it = mDeathNotifications.begin();
	it != mDeathNotifications.end(); ) {
	sp<IComponentListener> listener = it->first.promote();
	if (!listener) {
	++it;
	continue;
	}
	DeathNotifications &deathNotifications = it->second;

	nsecs_t timeSinceLastNotifiedNs =
	timeNowNs - deathNotifications.lastSentNs;
	// If not enough time has passed since the last callback, leave the
	// notifications for this listener untouched for now and retry
	// later.
	if (timeSinceLastNotifiedNs < notificationIntervalNs) {
	retry = true;
	timeToRetryNs = std::min(timeToRetryNs,
	notificationIntervalNs - timeSinceLastNotifiedNs);
	LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
	<< "Notifications for listener @ "
	<< std::hex << listener.get()
	<< " will be postponed.";
	++it;
	continue;
	}

	// If enough time has passed since the last notification to this
	// listener but there are currently no pending notifications, the
	// listener can be removed from mDeathNotifications---there is no
	// need to keep track of the last notification time anymore.
	if (deathNotifications.count == 0) {
	it = mDeathNotifications.erase(it);
	continue;
	}

	// Create the argument for the callback.
	notifications.emplace_back(listener, deathNotifications.count);
	hidl_vec<IComponentListener::InputBuffer> &inputBuffers =
	notifications.back().inputBuffers;
	size_t i = 0;
	for (std::pair<const uint64_t, std::vector<size_t>>& p :
	deathNotifications.indices) {
	uint64_t frameIndex = p.first;
	const std::vector<size_t> &bufferIndices = p.second;
	for (const size_t& bufferIndex : bufferIndices) {
	IComponentListener::InputBuffer &inputBuffer
	= inputBuffers[i++];
	inputBuffer.arrayIndex = bufferIndex;
	inputBuffer.frameIndex = frameIndex;
	}
	}

	// Clear deathNotifications for this listener and set retry to true
	// so processNotifications will be called again. This will
	// guarantee that a listener with no pending notifications will
	// eventually be removed from mDeathNotifications after
	// mNotificationIntervalNs nanoseconds has passed.
	retry = true;
	deathNotifications.indices.clear();
	deathNotifications.count = 0;
	deathNotifications.lastSentNs = timeNowNs;
	++it;
	}
	}

	// Call onInputBuffersReleased() outside the lock to avoid deadlock.
	for (const Notification& notification : notifications) {
	if (!notification.listener->onInputBuffersReleased(
	notification.inputBuffers).isOk()) {
	// This may trigger if the client has died.
	LOG(DEBUG) << "InputBufferManager::processNotifications -- "
	<< "failed to send death notifications to "
	<< "listener @ 0x" << std::hex
	<< notification.listener.get()
	<< std::dec << ".";
	} else {
	#if LOG_NDEBUG == 0
	std::stringstream inputBufferLog;
	for (const IComponentListener::InputBuffer& inputBuffer :
	notification.inputBuffers) {
	inputBufferLog << " (" << inputBuffer.frameIndex
	<< ", " << inputBuffer.arrayIndex
	<< ")";
	}
	LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
	<< "death notifications sent to "
	<< "listener @ 0x" << std::hex
	<< notification.listener.get()
	<< std::dec
	<< " with these (frameIndex, bufferIndex) pairs:"
	<< inputBufferLog.str();
	#endif
	}
	}
	#if LOG_NDEBUG == 0
	if (retry) {
	LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
	<< "will retry again in " << *timeToRetryNs << "ns.";
	} else {
	LOG(VERBOSE) << "InputBufferManager::processNotifications -- "
	<< "no pending death notifications.";
	}
	#endif
	return retry;
	}

	void InputBufferManager::main() {
	LOG(VERBOSE) << "InputBufferManager main -- started.";
	nsecs_t timeToRetryNs;
	while (true) {
	std::unique_lock<std::mutex> lock(mMutex);
	while (mDeathNotifications.empty()) {
	mOnBufferDestroyed.wait(lock);
	}
	lock.unlock();
	while (processNotifications(&timeToRetryNs)) {
	std::this_thread::sleep_for(
	std::chrono::nanoseconds(timeToRetryNs));
	}
	}
	}

	InputBufferManager::InputBufferManager()
	: mMainThread{&InputBufferManager::main, this} {
	}

	InputBufferManager& InputBufferManager::getInstance() {
	static InputBufferManager instance{};
	return instance;
	}

	} // namespace utils
	} // namespace V1_0
	} // namespace c2
	} // namespace media
	} // namespace hardware
	} // namespace android