| // Copyright 2014 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; |
| |
| import com.google.common.collect.Interner; |
| import com.google.devtools.build.lib.actions.FileValue; |
| import com.google.devtools.build.lib.concurrent.BlazeInterners; |
| import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable; |
| import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe; |
| import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec; |
| import com.google.devtools.build.lib.vfs.RootedPath; |
| import com.google.devtools.build.skyframe.AbstractSkyKey; |
| import com.google.devtools.build.skyframe.SkyFunctionName; |
| import com.google.devtools.build.skyframe.SkyValue; |
| import java.util.Objects; |
| |
| /** |
| * A value that represents the dirents (name and type of child entries) in a given directory under a |
| * given package path root, fully accounting for symlinks in the directory's path. Anything in |
| * Skyframe that cares about the contents of a directory should have a dependency on the |
| * corresponding {@link DirectoryListingValue}. |
| * |
| * <p>Note that dirents that are themselves symlinks are <b>not</b> resolved. Consumers of such a |
| * dirent are responsible for resolving the symlink entry via an appropriate {@link FileValue}. |
| * This is a little onerous, but correct: we do not need to reread the directory when a symlink |
| * inside it changes (or, more generally, when the *contents* of a dirent changes), therefore the |
| * {@link DirectoryListingValue} value should not be invalidated in that case. |
| */ |
| @Immutable |
| @ThreadSafe |
| public abstract class DirectoryListingValue implements SkyValue { |
| |
| /** |
| * Returns the directory entries for this directory, in a stable order. |
| * |
| * <p>Symlinks are not expanded. |
| */ |
| public Dirents getDirents() { |
| return getDirectoryListingStateValue().getDirents(); |
| } |
| |
| public abstract DirectoryListingStateValue getDirectoryListingStateValue(); |
| |
| /** |
| * Returns a {@link Key} for getting the directory entries of the given directory. The given path |
| * is assumed to be an existing directory (e.g. via {@link FileValue#isDirectory} or from a |
| * directory listing on its parent directory). |
| */ |
| @ThreadSafe |
| public static Key key(RootedPath directoryUnderRoot) { |
| return Key.create(directoryUnderRoot); |
| } |
| |
| @AutoCodec.VisibleForSerialization |
| @AutoCodec |
| static class Key extends AbstractSkyKey<RootedPath> { |
| private static final Interner<Key> interner = BlazeInterners.newWeakInterner(); |
| |
| private Key(RootedPath arg) { |
| super(arg); |
| } |
| |
| @AutoCodec.VisibleForSerialization |
| @AutoCodec.Instantiator |
| static Key create(RootedPath arg) { |
| return interner.intern(new Key(arg)); |
| } |
| |
| @Override |
| public SkyFunctionName functionName() { |
| return SkyFunctions.DIRECTORY_LISTING; |
| } |
| } |
| |
| static DirectoryListingValue value(RootedPath dirRootedPath, FileValue dirFileValue, |
| DirectoryListingStateValue realDirectoryListingStateValue) { |
| return dirFileValue.realRootedPath().equals(dirRootedPath) |
| ? new RegularDirectoryListingValue(realDirectoryListingStateValue) |
| : new DifferentRealPathDirectoryListingValue(dirFileValue.realRootedPath(), |
| realDirectoryListingStateValue); |
| } |
| |
| /** Normal {@link DirectoryListingValue}. */ |
| @ThreadSafe |
| public static final class RegularDirectoryListingValue extends DirectoryListingValue { |
| |
| private final DirectoryListingStateValue directoryListingStateValue; |
| |
| public RegularDirectoryListingValue(DirectoryListingStateValue directoryListingStateValue) { |
| this.directoryListingStateValue = directoryListingStateValue; |
| } |
| |
| @Override |
| public DirectoryListingStateValue getDirectoryListingStateValue() { |
| return directoryListingStateValue; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (this == obj) { |
| return true; |
| } |
| if (!(obj instanceof RegularDirectoryListingValue)) { |
| return false; |
| } |
| RegularDirectoryListingValue other = (RegularDirectoryListingValue) obj; |
| return directoryListingStateValue.equals(other.directoryListingStateValue); |
| } |
| |
| @Override |
| public int hashCode() { |
| return directoryListingStateValue.hashCode(); |
| } |
| } |
| |
| /** A {@link DirectoryListingValue} with a different root. */ |
| @ThreadSafe |
| public static final class DifferentRealPathDirectoryListingValue extends DirectoryListingValue { |
| |
| private final RootedPath realDirRootedPath; |
| private final DirectoryListingStateValue directoryListingStateValue; |
| |
| public DifferentRealPathDirectoryListingValue(RootedPath realDirRootedPath, |
| DirectoryListingStateValue directoryListingStateValue) { |
| this.realDirRootedPath = realDirRootedPath; |
| this.directoryListingStateValue = directoryListingStateValue; |
| } |
| |
| public RootedPath getRealDirRootedPath() { |
| return realDirRootedPath; |
| } |
| |
| @Override |
| public DirectoryListingStateValue getDirectoryListingStateValue() { |
| return directoryListingStateValue; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (this == obj) { |
| return true; |
| } |
| if (!(obj instanceof DifferentRealPathDirectoryListingValue)) { |
| return false; |
| } |
| DifferentRealPathDirectoryListingValue other = (DifferentRealPathDirectoryListingValue) obj; |
| return realDirRootedPath.equals(other.realDirRootedPath) |
| && directoryListingStateValue.equals(other.directoryListingStateValue); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(realDirRootedPath, directoryListingStateValue); |
| } |
| } |
| } |