Merge "Synchronize in LazyValue.get()" (92b71e56) · Commits · e / os / android_frameworks_base

core/java/android/os/BaseBundle.java

+7 −4

Original line number	Diff line number	Diff line
		@@ -260,6 +260,9 @@ public class BaseBundle {
		/**
		* Returns the value for key {@code key}.
		*
		* This call should always be made after {@link #unparcel()} or inside a lock after making sure
		* {@code mMap} is not null.
		*
		* @hide
		*/
		final Object getValue(String key) {
		@@ -270,15 +273,15 @@ public class BaseBundle {
		/**
		* Returns the value for a certain position in the array map.
		*
		* This call should always be made after {@link #unparcel()} or inside a lock after making sure
		* {@code mMap} is not null.
		*
		* @hide
		*/
		final Object getValueAt(int i) {
		Object object = mMap.valueAt(i);
		if (object instanceof Supplier<?>) {
		Supplier<?> supplier = (Supplier<?>) object;
		synchronized (this) {
		object = supplier.get();
		}
		object = ((Supplier<?>) object).get();
		mMap.setValueAt(i, object);
		}
		return object;

core/java/android/os/Parcel.java

+54 −34

Original line number	Diff line number	Diff line
		@@ -16,6 +16,8 @@

		package android.os;

		import static java.util.Objects.requireNonNull;

		import android.annotation.NonNull;
		import android.annotation.Nullable;
		import android.annotation.TestApi;
		@@ -3412,12 +3414,19 @@ public final class Parcel {
		private final int mLength;
		private final int mType;
		@Nullable private final ClassLoader mLoader;
		@Nullable private Parcel mSource;
		@Nullable private Object mObject;
		@Nullable private Parcel mValueParcel;
		@Nullable private volatile Parcel mValueParcel;

		/**
		* This goes from non-null to null once. Always check the nullability of this object before
		* performing any operations, either involving itself or mObject since the happens-before
		* established by this volatile will guarantee visibility of either. We can assume this
		* parcel won't change anymore.
		*/
		@Nullable private volatile Parcel mSource;

		LazyValue(Parcel source, int position, int length, int type, @Nullable ClassLoader loader) {
		mSource = source;
		mSource = requireNonNull(source);
		mPosition = position;
		mLength = length;
		mType = type;
		@@ -3426,38 +3435,41 @@ public final class Parcel {

		@Override
		public Object get() {
		if (mObject == null) {
		int restore = mSource.dataPosition();
		Parcel source = mSource;
		if (source != null) {
		synchronized (source) {
		int restore = source.dataPosition();
		try {
		mSource.setDataPosition(mPosition);
		mObject = mSource.readValue(mLoader);
		source.setDataPosition(mPosition);
		mObject = source.readValue(mLoader);
		} finally {
		mSource.setDataPosition(restore);
		source.setDataPosition(restore);
		}
		mSource = null;
		if (mValueParcel != null) {
		mValueParcel.recycle();
		mValueParcel = null;
		}
		}
		return mObject;
		}

		public void writeToParcel(Parcel out) {
		if (mObject == null) {
		out.appendFrom(mSource, mPosition, mLength + 8);
		Parcel source = mSource;
		if (source != null) {
		out.appendFrom(source, mPosition, mLength + 8);
		} else {
		out.writeValue(mObject);
		}
		}

		public boolean hasFileDescriptors() {
		return getValueParcel().hasFileDescriptors();
		Parcel source = mSource;
		return (source != null)
		? getValueParcel(source).hasFileDescriptors()
		: Parcel.hasFileDescriptors(mObject);
		}

		@Override
		public String toString() {
		return mObject == null
		return (mSource != null)
		? "Supplier{" + valueTypeToString(mType) + "@" + mPosition + "+" + mLength + '}'
		: "Supplier{" + mObject + "}";
		}
		@@ -3476,41 +3488,49 @@ public final class Parcel {
		return false;
		}
		LazyValue value = (LazyValue) other;
		// Check if they are either both serialized or both deserialized
		if ((mObject == null) != (value.mObject == null)) {
		// Check if they are either both serialized or both deserialized.
		Parcel source = mSource;
		Parcel otherSource = value.mSource;
		if ((source == null) != (otherSource == null)) {
		return false;
		}
		// If both are deserialized, compare the live objects
		if (mObject != null) {
		return mObject.equals(value.mObject);
		// If both are deserialized, compare the live objects.
		if (source == null) {
		// Note that here it's guaranteed that both mObject references contain valid values
		// (possibly null) since mSource will have provided the memory barrier for those and
		// once deserialized we never go back to serialized state.
		return Objects.equals(mObject, value.mObject);
		}
		// Better safely fail here since this could mean we get different objects
		// Better safely fail here since this could mean we get different objects.
		if (!Objects.equals(mLoader, value.mLoader)) {
		return false;
		}
		// Otherwise compare metadata prior to comparing payload
		// Otherwise compare metadata prior to comparing payload.
		if (mType != value.mType \|\| mLength != value.mLength) {
		return false;
		}
		// Finally we compare the payload
		return getValueParcel().compareData(value.getValueParcel()) == 0;
		// Finally we compare the payload.
		return getValueParcel(source).compareData(value.getValueParcel(otherSource)) == 0;
		}

		@Override
		public int hashCode() {
		return Objects.hash(mObject, mLoader, mType, mLength);
		// Accessing mSource first to provide memory barrier for mObject
		return Objects.hash(mSource == null, mObject, mLoader, mType, mLength);
		}

		/** This extracts the parcel section responsible for the object and returns it. */
		private Parcel getValueParcel() {
		if (mValueParcel == null) {
		mValueParcel = Parcel.obtain();
		private Parcel getValueParcel(Parcel source) {
		Parcel parcel = mValueParcel;
		if (parcel == null) {
		parcel = Parcel.obtain();
		// mLength is the length of object representation, excluding the type and length.
		// mPosition is the position of the entire value container, right before the type.
		// So, we add 4 bytes for the type + 4 bytes for the length written.
		mValueParcel.appendFrom(mSource, mPosition, mLength + 8);
		parcel.appendFrom(source, mPosition, mLength + 8);
		mValueParcel = parcel;
		}
		return mValueParcel;
		return parcel;
		}
		}