| // 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.ImmutableList; |
| import com.google.common.collect.Interner; |
| import com.google.devtools.build.lib.concurrent.BlazeInterners; |
| 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.SkyFunction; |
| import com.google.devtools.build.skyframe.SkyFunctionName; |
| import com.google.devtools.build.skyframe.SkyKey; |
| |
| /** |
| * A {@link SkyFunction} that has the side effect of reporting a file symlink cycle. This is |
| * achieved by forcing the same key for two logically equivalent cycles |
| * (e.g. ['a' -> 'b' -> 'c' -> 'a'] and ['b' -> 'c' -> 'a' -> 'b']), and letting Skyframe do its |
| * magic. |
| */ |
| public class FileSymlinkCycleUniquenessFunction |
| extends AbstractChainUniquenessFunction<RootedPath> { |
| |
| static SkyKey key(ImmutableList<RootedPath> cycle) { |
| return Key.create(ChainUniquenessUtils.canonicalize(cycle)); |
| } |
| |
| @AutoCodec.VisibleForSerialization |
| @AutoCodec |
| static class Key extends AbstractSkyKey<ImmutableList<RootedPath>> { |
| private static final Interner<Key> interner = BlazeInterners.newWeakInterner(); |
| |
| private Key(ImmutableList<RootedPath> arg) { |
| super(arg); |
| } |
| |
| @AutoCodec.VisibleForSerialization |
| @AutoCodec.Instantiator |
| static Key create(ImmutableList<RootedPath> arg) { |
| return interner.intern(new Key(arg)); |
| } |
| |
| @Override |
| public SkyFunctionName functionName() { |
| return SkyFunctions.FILE_SYMLINK_CYCLE_UNIQUENESS; |
| } |
| } |
| |
| @Override |
| protected String elementToString(RootedPath elt) { |
| return elt.asPath().toString(); |
| } |
| |
| @Override |
| protected String getConciseDescription() { |
| return "circular symlinks"; |
| } |
| |
| @Override |
| protected String getHeaderMessage() { |
| return "[start of symlink cycle]"; |
| } |
| |
| @Override |
| protected String getFooterMessage() { |
| return "[end of symlink cycle]"; |
| } |
| } |