Merge "SoundPool: Clean up JNI weak reference handling" into tm-dev am: 6a1b6bc9

import java.io.File;

import java.io.FileDescriptor;

import java.lang.ref.WeakReference;

import java.util.concurrent.atomic.AtomicReference;

        super(attributes, AudioPlaybackConfiguration.PLAYER_TYPE_JAM_SOUNDPOOL);

        // do native setup

        if (native_setup(new WeakReference<SoundPool>(this),

                maxStreams, attributes, getCurrentOpPackageName()) != 0) {

        if (native_setup(maxStreams, attributes, getCurrentOpPackageName()) != 0) {

            throw new RuntimeException("Native setup failed");

        }

        mAttributes = attributes;

    private native final int _load(FileDescriptor fd, long offset, long length, int priority);

    private native final int native_setup(Object weakRef, int maxStreams,

    private native int native_setup(int maxStreams,

            @NonNull Object/*AudioAttributes*/ attributes, @NonNull String opPackageName);

    private native final int _play(int soundID, float leftVolume, float rightVolume,

    // post event from native code to message handler

    @SuppressWarnings("unchecked")

    private static void postEventFromNative(Object ref, int msg, int arg1, int arg2, Object obj) {

        SoundPool soundPool = ((WeakReference<SoundPool>) ref).get();

        if (soundPool == null) {

            return;

        }

        Handler eventHandler = soundPool.mEventHandler.get();

    private void postEventFromNative(int msg, int arg1, int arg2, Object obj) {

        Handler eventHandler = mEventHandler.get();

        if (eventHandler == null) {

            return;

        }

        Message message = eventHandler.obtainMessage(msg, arg1, arg2, obj);

        eventHandler.sendMessage(message);

    }

// Note std::remove_ptr_t<NonPointerType> == NonPointerType.

static_assert(std::is_same_v<JObjectValue*, jobject>);

// *jweak is needed to fit the jweak into a std::shared_ptr.

// This is the Android type _jobject, but we derive this type as JWeakValue.

using JWeakValue = std::remove_pointer_t<jweak>; // this is just _jobject

// Check that jweak is really a pointer to JWeakValue.

static_assert(std::is_same_v<JWeakValue*, jweak>);

// We store the ancillary data associated with a SoundPool object in a concurrent

// hash map indexed on the SoundPool native object pointer.

auto& getSoundPoolJavaRefManager() {

    static ConcurrentHashMap<SoundPool *, std::shared_ptr<JObjectValue>> concurrentHashMap;

    // Note this can store shared_ptrs to either jweak and jobject,

    // as the underlying type is identical.

    static ConcurrentHashMap<SoundPool *, std::shared_ptr<JWeakValue>> concurrentHashMap;

    return concurrentHashMap;

}

// https://developer.android.com/training/articles/perf-jni

// https://android-developers.googleblog.com/2011/11/jni-local-reference-changes-in-ics.html

//

// Consider using a weak reference if this is self-referential.

[[maybe_unused]]

inline auto make_shared_globalref_from_localref(JNIEnv *env, jobject localRef) {

    return std::shared_ptr<JObjectValue>(

            env->NewGlobalRef(localRef),

            });

}

// Create a weak global reference from local ref.

inline auto make_shared_weakglobalref_from_localref(JNIEnv *env, jobject localRef) {

    return std::shared_ptr<JWeakValue>(

            env->NewWeakGlobalRef(localRef),

            [](JWeakValue* weak) { // cannot cache env as don't know which thread we're on.

                if (weak != nullptr) AndroidRuntime::getJNIEnv()->DeleteWeakGlobalRef(weak);

            });

}

// std::unique_ptr<> does not store a type-erased deleter like std::shared_ptr<>.

// Define a lambda here to use for the std::unique_ptr<> type definition.

auto LocalRefDeleter = [](JObjectValue* object) {

    if (object != nullptr) AndroidRuntime::getJNIEnv()->DeleteLocalRef(object);

};

// Create a local reference from another reference.

// This is a unique_ptr to avoid the temptation of sharing with other threads.

//

// This can be used to promote a WeakGlobalRef jweak into a stable LocalRef jobject.

//

inline auto make_unique_localref_from_ref(JNIEnv *env, jobject object) {

    return std::unique_ptr<JObjectValue, decltype(LocalRefDeleter)>(

            env->NewLocalRef(object),

            LocalRefDeleter);

}

} // namespace

static const char* const kAudioAttributesClassPathName = "android/media/AudioAttributes";

        return;

    }

    JNIEnv *env = AndroidRuntime::getJNIEnv();

    env->CallStaticVoidMethod(

            fields.mSoundPoolClass, fields.mPostEvent,

            weakRef.get(), event.mMsg, event.mArg1, event.mArg2,

            nullptr /* object */);

    // "promote" the WeakGlobalRef into a LocalRef.

    auto javaSoundPool = make_unique_localref_from_ref(env, weakRef.get());

    if (!javaSoundPool) {

        ALOGW("%s: weak reference promotes to null (release() not called?), "

                "ignoring callback", __func__);

        return;

    }

    env->CallVoidMethod(javaSoundPool.get(), fields.mPostEvent,

            event.mMsg, event.mArg1, event.mArg2, nullptr /* object */);

    if (env->ExceptionCheck() != JNI_FALSE) {

        ALOGE("%s: Uncaught exception returned from Java callback", __func__);

}

static jint

android_media_SoundPool_native_setup(JNIEnv *env, jobject thiz, jobject weakRef,

android_media_SoundPool_native_setup(JNIEnv *env, jobject thiz,

        jint maxChannels, jobject jaa, jstring opPackageName)

{

    ALOGV("android_media_SoundPool_native_setup");

    auto oldSoundPool = setSoundPool(env, thiz, soundPool);

    // register Java SoundPool WeakRef using native SoundPool * as the key, for the callback.

    auto oldSoundPoolJavaRef = getSoundPoolJavaRefManager().set(

            soundPool.get(), make_shared_globalref_from_localref(env, weakRef));

            soundPool.get(), make_shared_weakglobalref_from_localref(env, thiz));

    ALOGW_IF(oldSoundPool != nullptr, "%s: Aliased SoundPool object %p",

            __func__, oldSoundPool.get());

        (void *)android_media_SoundPool_setRate

    },

    {   "native_setup",

        "(Ljava/lang/Object;ILjava/lang/Object;Ljava/lang/String;)I",

        "(ILjava/lang/Object;Ljava/lang/String;)I",

        (void*)android_media_SoundPool_native_setup

    },

    {   "native_release",

        return result;

    }

    fields.mPostEvent = env->GetStaticMethodID(clazz, "postEventFromNative",

                                               "(Ljava/lang/Object;IIILjava/lang/Object;)V");

    fields.mPostEvent = env->GetMethodID(

            clazz, "postEventFromNative", "(IIILjava/lang/Object;)V");

    if (fields.mPostEvent == nullptr) {

        ALOGE("Can't find android/media/SoundPool.postEventFromNative");

        return result;