| // Copyright 2024 The Bazel Authors. All rights reserved. |
| // |
| // 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 com.google.devtools.build.lib.skyframe.serialization; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.collect.ImmutableClassToInstanceMap; |
| import com.google.protobuf.ByteString; |
| import com.google.protobuf.CodedOutputStream; |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.io.OutputStream; |
| import java.util.HashSet; |
| import java.util.Set; |
| import javax.annotation.Nullable; |
| |
| /** A stateful serializer that emits backreferences instead of reserializing duplicate objects. */ |
| abstract class MemoizingSerializationContext extends SerializationContext { |
| private final Memoizer.Serializer serializer = new Memoizer.Serializer(); |
| private final Set<Class<?>> explicitlyAllowedClasses = new HashSet<>(); |
| |
| @VisibleForTesting // private |
| static MemoizingSerializationContext createForTesting( |
| ObjectCodecRegistry codecRegistry, ImmutableClassToInstanceMap<Object> dependencies) { |
| return new MemoizingSerializationContextImpl(codecRegistry, dependencies); |
| } |
| |
| MemoizingSerializationContext( |
| ObjectCodecRegistry codecRegistry, ImmutableClassToInstanceMap<Object> dependencies) { |
| super(codecRegistry, dependencies); |
| } |
| |
| static byte[] serializeToBytes( |
| ObjectCodecRegistry codecRegistry, |
| ImmutableClassToInstanceMap<Object> dependencies, |
| @Nullable Object subject, |
| int outputCapacity, |
| int bufferCapacity) |
| throws SerializationException { |
| ByteArrayOutputStream bytesOut = new ByteArrayOutputStream(outputCapacity); |
| serializeToStream(codecRegistry, dependencies, subject, bytesOut, bufferCapacity); |
| return bytesOut.toByteArray(); |
| } |
| |
| static ByteString serializeToByteString( |
| ObjectCodecRegistry codecRegistry, |
| ImmutableClassToInstanceMap<Object> dependencies, |
| @Nullable Object subject, |
| int outputCapacity, |
| int bufferCapacity) |
| throws SerializationException { |
| ByteString.Output bytesOut = ByteString.newOutput(outputCapacity); |
| serializeToStream(codecRegistry, dependencies, subject, bytesOut, bufferCapacity); |
| return bytesOut.toByteString(); |
| } |
| |
| @Override |
| public final void addExplicitlyAllowedClass(Class<?> allowedClass) { |
| explicitlyAllowedClasses.add(allowedClass); |
| } |
| |
| @Override |
| public final <T> void checkClassExplicitlyAllowed(Class<T> allowedClass, T objectForDebugging) |
| throws SerializationException { |
| if (!explicitlyAllowedClasses.contains(allowedClass)) { |
| throw new SerializationException( |
| allowedClass |
| + " not explicitly allowed (allowed classes were: " |
| + explicitlyAllowedClasses |
| + ") and object is " |
| + objectForDebugging); |
| } |
| } |
| |
| @Override |
| final void serializeWithCodec(ObjectCodec<Object> codec, Object obj, CodedOutputStream codedOut) |
| throws SerializationException, IOException { |
| serializer.serialize(this, obj, codec, codedOut); |
| } |
| |
| @Override |
| final boolean writeBackReferenceIfMemoized(Object obj, CodedOutputStream codedOut) |
| throws IOException { |
| int memoizedIndex = serializer.getMemoizedIndex(obj); |
| if (memoizedIndex == -1) { |
| return false; |
| } |
| // Subtracts 1 so it will be negative and not collide with null. |
| codedOut.writeSInt32NoTag(-memoizedIndex - 1); |
| return true; |
| } |
| |
| @Override |
| public final boolean isMemoizing() { |
| return true; |
| } |
| |
| private static void serializeToStream( |
| ObjectCodecRegistry codecRegistry, |
| ImmutableClassToInstanceMap<Object> dependencies, |
| @Nullable Object subject, |
| OutputStream output, |
| int bufferCapacity) |
| throws SerializationException { |
| CodedOutputStream codedOut = CodedOutputStream.newInstance(output, bufferCapacity); |
| try { |
| new MemoizingSerializationContextImpl(codecRegistry, dependencies) |
| .serialize(subject, codedOut); |
| codedOut.flush(); |
| } catch (IOException e) { |
| throw new SerializationException("Failed to serialize " + subject, e); |
| } |
| } |
| |
| /** |
| * This mainly exists to restrict use of {@link MemoizingSerializationContext}'s constructor. |
| * |
| * <p>It's also slightly cleaner for {@link SharedValueSerializationContext} to not inherit the |
| * implementation of {@link #getFreshContext}. |
| */ |
| private static final class MemoizingSerializationContextImpl |
| extends MemoizingSerializationContext { |
| private MemoizingSerializationContextImpl( |
| ObjectCodecRegistry codecRegistry, ImmutableClassToInstanceMap<Object> dependencies) { |
| super(codecRegistry, dependencies); |
| } |
| |
| @Override |
| public MemoizingSerializationContext getFreshContext() { |
| return new MemoizingSerializationContextImpl(getCodecRegistry(), getDependencies()); |
| } |
| } |
| } |