Utilities for managing event listeners from AudioService (91f0baa8) · Commits · e / os / android_frameworks_base

media/java/android/media/AudioManager.java

+59 −200

Original line number	Diff line number	Diff line
		@@ -40,6 +40,7 @@ import android.content.ComponentName;
		import android.content.Context;
		import android.content.Intent;
		import android.media.AudioAttributes.AttributeSystemUsage;
		import android.media.CallbackUtil.ListenerInfo;
		import android.media.audiopolicy.AudioPolicy;
		import android.media.audiopolicy.AudioPolicy.AudioPolicyFocusListener;
		import android.media.audiopolicy.AudioProductStrategy;
		@@ -2900,77 +2901,31 @@ public class AudioManager {
		* List is lazy-initialized on first registration
		*/
		@GuardedBy("mModeListenerLock")
		private @Nullable ArrayList<ModeListenerInfo> mModeListeners;
		private @Nullable ArrayList<ListenerInfo<OnModeChangedListener>> mModeListeners;

		@GuardedBy("mModeListenerLock")
		private ModeDispatcherStub mModeDispatcherStub;

		private final class ModeDispatcherStub
		extends IAudioModeDispatcher.Stub {
		private final class ModeDispatcherStub extends IAudioModeDispatcher.Stub {

		@Override
		public void dispatchAudioModeChanged(int mode) {
		// make a shallow copy of listeners so callback is not executed under lock
		final ArrayList<ModeListenerInfo> modeListeners;
		synchronized (mModeListenerLock) {
		if (mModeListeners == null \|\| mModeListeners.size() == 0) {
		return;
		}
		modeListeners = (ArrayList<ModeListenerInfo>) mModeListeners.clone();
		}
		final long ident = Binder.clearCallingIdentity();
		public void register(boolean register) {
		try {
		for (ModeListenerInfo info : modeListeners) {
		info.mExecutor.execute(() ->
		info.mListener.onModeChanged(mode));
		}
		} finally {
		Binder.restoreCallingIdentity(ident);
		}
		}
		}

		private static class ModeListenerInfo {
		final @NonNull OnModeChangedListener mListener;
		final @NonNull Executor mExecutor;

		ModeListenerInfo(OnModeChangedListener listener, Executor exe) {
		mListener = listener;
		mExecutor = exe;
		}
		}

		@GuardedBy("mModeListenerLock")
		private boolean hasModeListener(OnModeChangedListener listener) {
		return getModeListenerInfo(listener) != null;
		}

		@GuardedBy("mModeListenerLock")
		private @Nullable ModeListenerInfo getModeListenerInfo(
		OnModeChangedListener listener) {
		if (mModeListeners == null) {
		return null;
		}
		for (ModeListenerInfo info : mModeListeners) {
		if (info.mListener == listener) {
		return info;
		if (register) {
		getService().registerModeDispatcher(this);
		} else {
		getService().unregisterModeDispatcher(this);
		}
		} catch (RemoteException e) {
		e.rethrowFromSystemServer();
		}
		return null;
		}


		@GuardedBy("mModeListenerLock")
		/**
		* @return true if the listener was removed from the list
		*/
		private boolean removeModeListener(OnModeChangedListener listener) {
		final ModeListenerInfo infoToRemove = getModeListenerInfo(listener);
		if (infoToRemove != null) {
		mModeListeners.remove(infoToRemove);
		return true;
		@Override
		@SuppressLint("GuardedBy") // lock applied inside callListeners method
		public void dispatchAudioModeChanged(int mode) {
		CallbackUtil.callListeners(mModeListeners, mModeListenerLock,
		(listener) -> listener.onModeChanged(mode));
		}
		return false;
		}

		/**
		@@ -2982,30 +2937,14 @@ public class AudioManager {
		public void addOnModeChangedListener(
		@NonNull @CallbackExecutor Executor executor,
		@NonNull OnModeChangedListener listener) {
		Objects.requireNonNull(executor);
		Objects.requireNonNull(listener);
		synchronized (mModeListenerLock) {
		if (hasModeListener(listener)) {
		throw new IllegalArgumentException("attempt to call addOnModeChangedListener() "
		+ "on a previously registered listener");
		}
		// lazy initialization of the list of strategy-preferred device listener
		if (mModeListeners == null) {
		mModeListeners = new ArrayList<>();
		}
		final int oldCbCount = mModeListeners.size();
		mModeListeners.add(new ModeListenerInfo(listener, executor));
		if (oldCbCount == 0) {
		// register binder for callbacks
		if (mModeDispatcherStub == null) {
		mModeDispatcherStub = new ModeDispatcherStub();
		}
		try {
		getService().registerModeDispatcher(mModeDispatcherStub);
		} catch (RemoteException e) {
		throw e.rethrowFromSystemServer();
		}
		}
		final Pair<ArrayList<ListenerInfo<OnModeChangedListener>>, ModeDispatcherStub> res =
		CallbackUtil.addListener("addOnModeChangedListener",
		executor, listener, mModeListeners, mModeDispatcherStub,
		() -> new ModeDispatcherStub(),
		stub -> stub.register(true));
		mModeListeners = res.first;
		mModeDispatcherStub = res.second;
		}
		}

		@@ -3015,23 +2954,13 @@ public class AudioManager {
		* @param listener
		*/
		public void removeOnModeChangedListener(@NonNull OnModeChangedListener listener) {
		Objects.requireNonNull(listener);
		synchronized (mModeListenerLock) {
		if (!removeModeListener(listener)) {
		throw new IllegalArgumentException("attempt to call removeOnModeChangedListener() "
		+ "on an unregistered listener");
		}
		if (mModeListeners.size() == 0) {
		// unregister binder for callbacks
		try {
		getService().unregisterModeDispatcher(mModeDispatcherStub);
		} catch (RemoteException e) {
		throw e.rethrowFromSystemServer();
		} finally {
		mModeDispatcherStub = null;
		mModeListeners = null;
		}
		}
		final Pair<ArrayList<ListenerInfo<OnModeChangedListener>>, ModeDispatcherStub> res =
		CallbackUtil.removeListener("removeOnModeChangedListener",
		listener, mModeListeners, mModeDispatcherStub,
		stub -> stub.register(false));
		mModeListeners = res.first;
		mModeDispatcherStub = res.second;
		}
		}

		@@ -7646,31 +7575,15 @@ public class AudioManager {
		public void addOnCommunicationDeviceChangedListener(
		@NonNull @CallbackExecutor Executor executor,
		@NonNull OnCommunicationDeviceChangedListener listener) {
		Objects.requireNonNull(executor);
		Objects.requireNonNull(listener);
		synchronized (mCommDevListenerLock) {
		if (hasCommDevListener(listener)) {
		throw new IllegalArgumentException(
		"attempt to call addOnCommunicationDeviceChangedListener() "
		+ "on a previously registered listener");
		}
		// lazy initialization of the list of strategy-preferred device listener
		if (mCommDevListeners == null) {
		mCommDevListeners = new ArrayList<>();
		}
		final int oldCbCount = mCommDevListeners.size();
		mCommDevListeners.add(new CommDevListenerInfo(listener, executor));
		if (oldCbCount == 0 && mCommDevListeners.size() > 0) {
		// register binder for callbacks
		if (mCommDevDispatcherStub == null) {
		mCommDevDispatcherStub = new CommunicationDeviceDispatcherStub();
		}
		try {
		getService().registerCommunicationDeviceDispatcher(mCommDevDispatcherStub);
		} catch (RemoteException e) {
		throw e.rethrowFromSystemServer();
		}
		}
		final Pair<ArrayList<ListenerInfo<OnCommunicationDeviceChangedListener>>,
		CommunicationDeviceDispatcherStub> res =
		CallbackUtil.addListener("addOnCommunicationDeviceChangedListener",
		executor, listener, mCommDevListeners, mCommDevDispatcherStub,
		() -> new CommunicationDeviceDispatcherStub(),
		stub -> stub.register(true));
		mCommDevListeners = res.first;
		mCommDevDispatcherStub = res.second;
		}
		}

		@@ -7681,25 +7594,14 @@ public class AudioManager {
		*/
		public void removeOnCommunicationDeviceChangedListener(
		@NonNull OnCommunicationDeviceChangedListener listener) {
		Objects.requireNonNull(listener);
		synchronized (mCommDevListenerLock) {
		if (!removeCommDevListener(listener)) {
		throw new IllegalArgumentException(
		"attempt to call removeOnCommunicationDeviceChangedListener() "
		+ "on an unregistered listener");
		}
		if (mCommDevListeners.size() == 0) {
		// unregister binder for callbacks
		try {
		getService().unregisterCommunicationDeviceDispatcher(
		mCommDevDispatcherStub);
		} catch (RemoteException e) {
		throw e.rethrowFromSystemServer();
		} finally {
		mCommDevDispatcherStub = null;
		mCommDevListeners = null;
		}
		}
		final Pair<ArrayList<ListenerInfo<OnCommunicationDeviceChangedListener>>,
		CommunicationDeviceDispatcherStub> res =
		CallbackUtil.removeListener("removeOnCommunicationDeviceChangedListener",
		listener, mCommDevListeners, mCommDevDispatcherStub,
		stub -> stub.register(false));
		mCommDevListeners = res.first;
		mCommDevDispatcherStub = res.second;
		}
		}

		@@ -7709,17 +7611,8 @@ public class AudioManager {
		* List is lazy-initialized on first registration
		*/
		@GuardedBy("mCommDevListenerLock")
		private @Nullable ArrayList<CommDevListenerInfo> mCommDevListeners;

		private static class CommDevListenerInfo {
		final @NonNull OnCommunicationDeviceChangedListener mListener;
		final @NonNull Executor mExecutor;

		CommDevListenerInfo(OnCommunicationDeviceChangedListener listener, Executor exe) {
		mListener = listener;
		mExecutor = exe;
		}
		}
		private @Nullable
		ArrayList<ListenerInfo<OnCommunicationDeviceChangedListener>> mCommDevListeners;

		@GuardedBy("mCommDevListenerLock")
		private CommunicationDeviceDispatcherStub mCommDevDispatcherStub;
		@@ -7727,59 +7620,25 @@ public class AudioManager {
		private final class CommunicationDeviceDispatcherStub
		extends ICommunicationDeviceDispatcher.Stub {

		@Override
		public void dispatchCommunicationDeviceChanged(int portId) {
		// make a shallow copy of listeners so callback is not executed under lock
		final ArrayList<CommDevListenerInfo> commDevListeners;
		synchronized (mCommDevListenerLock) {
		if (mCommDevListeners == null \|\| mCommDevListeners.size() == 0) {
		return;
		}
		commDevListeners = (ArrayList<CommDevListenerInfo>) mCommDevListeners.clone();
		}
		AudioDeviceInfo device = getDeviceForPortId(portId, GET_DEVICES_OUTPUTS);
		final long ident = Binder.clearCallingIdentity();
		public void register(boolean register) {
		try {
		for (CommDevListenerInfo info : commDevListeners) {
		info.mExecutor.execute(() ->
		info.mListener.onCommunicationDeviceChanged(device));
		}
		} finally {
		Binder.restoreCallingIdentity(ident);
		}
		}
		}

		@GuardedBy("mCommDevListenerLock")
		private @Nullable CommDevListenerInfo getCommDevListenerInfo(
		OnCommunicationDeviceChangedListener listener) {
		if (mCommDevListeners == null) {
		return null;
		}
		for (CommDevListenerInfo info : mCommDevListeners) {
		if (info.mListener == listener) {
		return info;
		if (register) {
		getService().registerCommunicationDeviceDispatcher(this);
		} else {
		getService().unregisterCommunicationDeviceDispatcher(this);
		}
		} catch (RemoteException e) {
		e.rethrowFromSystemServer();
		}
		return null;
		}

		@GuardedBy("mCommDevListenerLock")
		private boolean hasCommDevListener(OnCommunicationDeviceChangedListener listener) {
		return getCommDevListenerInfo(listener) != null;
		}

		@GuardedBy("mCommDevListenerLock")
		/**
		* @return true if the listener was removed from the list
		*/
		private boolean removeCommDevListener(OnCommunicationDeviceChangedListener listener) {
		final CommDevListenerInfo infoToRemove = getCommDevListenerInfo(listener);
		if (infoToRemove != null) {
		mCommDevListeners.remove(infoToRemove);
		return true;
		@Override
		@SuppressLint("GuardedBy") // lock applied inside callListeners method
		public void dispatchCommunicationDeviceChanged(int portId) {
		AudioDeviceInfo device = getDeviceForPortId(portId, GET_DEVICES_OUTPUTS);
		CallbackUtil.callListeners(mCommDevListeners, mCommDevListenerLock,
		(listener) -> listener.onCommunicationDeviceChanged(device));
		}
		return false;
		}

		//---------------------------------------------------------

media/java/android/media/CallbackUtil.java

0 → 100644

+224 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2021 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.
		*/

		package android.media;

		import android.annotation.NonNull;
		import android.annotation.Nullable;
		import android.media.permission.ClearCallingIdentityContext;
		import android.media.permission.SafeCloseable;
		import android.util.Log;
		import android.util.Pair;

		import java.util.ArrayList;
		import java.util.Objects;
		import java.util.concurrent.Executor;

		/**
		* @hide
		* A utility class to implement callback listeners and their management.
		* This is meant to be used for lazily-initialized listener lists and stubs for event reception,
		* typically received from server (e.g. AudioService).
		*/

		/package/ class CallbackUtil {

		private static final String TAG = "CallbackUtil";

		/**
		* Container class to store a listener and associated Executor
		* @param <T> the type of the listener
		*/
		static class ListenerInfo<T> {
		final @NonNull T mListener;
		final @NonNull Executor mExecutor;

		ListenerInfo(@NonNull T listener, @NonNull Executor exe) {
		mListener = listener;
		mExecutor = exe;
		}
		}

		/**
		* Finds the listener information (listener + Executor) in a given list of listeners
		* @param listener the listener to find
		* @param listeners the list of listener informations, can be null if not instantiated yet
		* @param <T> the type of the listeners
		* @return null if the listener is not in the given list of listener informations
		*/
		static <T> @Nullable ListenerInfo<T> getListenerInfo(
		@NonNull T listener, @Nullable ArrayList<ListenerInfo<T>> listeners) {
		if (listeners == null) {
		return null;
		}
		for (ListenerInfo<T> info : listeners) {
		if (info.mListener == listener) {
		return info;
		}
		}
		return null;
		}

		/**
		* Returns true if the given listener is present in the list of listener informations
		* @param listener the listener to find
		* @param listeners the list of listener informations, can be null if not instantiated yet
		* @param <T> the type of the listeners
		* @return true if the listener is in the list
		*/
		static <T> boolean hasListener(@NonNull T listener,
		@Nullable ArrayList<ListenerInfo<T>> listeners) {
		return getListenerInfo(listener, listeners) != null;
		}

		/**
		* Removes the given listener from the list of listener informations
		* @param listener the listener to remove
		* @param listeners the list of listener informations, can be null if not instantiated yet
		* @param <T> the type of the listeners
		* @return true if the listener was found and removed from the list, false otherwise
		*/
		static <T> boolean removeListener(@NonNull T listener,
		@Nullable ArrayList<ListenerInfo<T>> listeners) {
		final ListenerInfo<T> infoToRemove = getListenerInfo(listener, listeners);
		if (infoToRemove != null) {
		listeners.remove(infoToRemove);
		return true;
		}
		return false;
		}

		/**
		* Adds a listener and associated Executor in the list of listeners.
		* This method handles the lazy initialization of both the list of listeners and the stub
		* used to receive the events that will be forwarded to the listener, see the returned pair
		* for the updated references.
		* @param methodName the name of the method calling this, for inclusion in the
		* string in case of IllegalArgumentException
		* @param executor the Executor for the listener
		* @param listener the listener to add
		* @param listeners the list of listener informations, can be null if not instantiated yet
		* @param dispatchStub the stub that receives the events to be forwarded to the listeners,
		* can be null if not instantiated yet
		* @param newStub the function to create a new stub if needed
		* @param registerStub the function for the stub registration if needed
		* @param <T> the type of the listener interface
		* @param <S> the type of the event receiver stub
		* @return a pair of the listener list and the event receiver stub which may have been
		* initialized if needed (e.g. on the first ever addition of a listener)
		*/
		static <T, S> Pair<ArrayList<ListenerInfo<T>>, S> addListener(String methodName,
		@NonNull Executor executor,
		@NonNull T listener,
		@Nullable ArrayList<ListenerInfo<T>> listeners,
		@Nullable S dispatchStub,
		@NonNull java.util.function.Supplier<S> newStub,
		@NonNull java.util.function.Consumer<S> registerStub) {
		Objects.requireNonNull(executor);
		Objects.requireNonNull(listener);

		if (hasListener(listener, listeners)) {
		throw new IllegalArgumentException("attempt to call " + methodName
		+ "on a previously registered listener");
		}
		// lazy initialization of the list of strategy-preferred device listener
		if (listeners == null) {
		listeners = new ArrayList<>();
		}
		if (listeners.size() == 0) {
		// register binder for callbacks
		if (dispatchStub == null) {
		try {
		dispatchStub = newStub.get();
		} catch (Exception e) {
		Log.e(TAG, "Exception while creating stub in " + methodName, e);
		return new Pair<>(null, null);
		}
		}
		registerStub.accept(dispatchStub);
		}
		listeners.add(new ListenerInfo<T>(listener, executor));
		return new Pair(listeners, dispatchStub);
		}

		/**
		* Removes a listener from the list of listeners.
		* This method handles the freeing of both the list of listeners and the stub
		* used to receive the events that will be forwarded to the listener,see the returned pair
		* for the updated references.
		* @param methodName the name of the method calling this, for inclusion in the
		* string in case of IllegalArgumentException
		* @param listener the listener to remove
		* @param listeners the list of listener informations, can be null if not instantiated yet
		* @param dispatchStub the stub that receives the events to be forwarded to the listeners,
		* can be null if not instantiated yet
		* @param unregisterStub the function to unregister the stub if needed
		* @param <T> the type of the listener interface
		* @param <S> the type of the event receiver stub
		* @return a pair of the listener list and the event receiver stub which may have been
		* changed if needed (e.g. on the removal of the last listener)
		*/
		static <T, S> Pair<ArrayList<ListenerInfo<T>>, S> removeListener(String methodName,
		@NonNull T listener,
		@Nullable ArrayList<ListenerInfo<T>> listeners,
		@Nullable S dispatchStub,
		@NonNull java.util.function.Consumer<S> unregisterStub) {
		Objects.requireNonNull(listener);

		if (!removeListener(listener, listeners)) {
		throw new IllegalArgumentException("attempt to call " + methodName
		+ "on an unregistered listener");
		}
		if (listeners.size() == 0) {
		unregisterStub.accept(dispatchStub);
		return new Pair<>(null, null);
		} else {
		return new Pair<>(listeners, dispatchStub);
		}
		}

		interface CallbackMethod<T> {
		void callbackMethod(T listener);
		}

		/**
		* Exercise the callback of the listeners
		* @param listeners the list of listeners
		* @param listenerLock the lock guarding the list of listeners
		* @param callback the function to call for each listener
		* @param <T> the type of the listener interface
		*/
		static <T> void callListeners(
		@Nullable ArrayList<ListenerInfo<T>> listeners,
		@NonNull Object listenerLock,
		@NonNull CallbackMethod<T> callback) {
		Objects.requireNonNull(listenerLock);
		// make a shallow copy of listeners so callback is not executed under lock
		final ArrayList<ListenerInfo<T>> listenersShallowCopy;
		synchronized (listenerLock) {
		if (listeners == null \|\| listeners.size() == 0) {
		return;
		}
		listenersShallowCopy = (ArrayList<ListenerInfo<T>>) listeners.clone();
		}
		try (SafeCloseable ignored = ClearCallingIdentityContext.create()) {
		for (ListenerInfo<T> info : listenersShallowCopy) {
		info.mExecutor.execute(() -> callback.callbackMethod(info.mListener));
		}
		}

		}
		}

media/java/android/media/Spatializer.java

+72 −227

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