| // Copyright 2015 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.query2.engine; |
| |
| import com.google.common.base.Function; |
| import com.google.common.collect.ImmutableList; |
| import com.google.devtools.build.lib.query2.engine.QueryEnvironment.Argument; |
| import com.google.devtools.build.lib.query2.engine.QueryEnvironment.ArgumentType; |
| import com.google.devtools.build.lib.query2.engine.QueryEnvironment.FilteringQueryFunction; |
| import com.google.devtools.build.lib.query2.engine.QueryEnvironment.QueryTaskFuture; |
| import com.google.devtools.build.lib.query2.engine.QueryEnvironment.ThreadSafeMutableSet; |
| import java.util.List; |
| import java.util.Set; |
| |
| /** |
| * A visible(x, y) query expression, which computes the subset of nodes in y that are visible from |
| * all nodes in x. |
| * |
| * <pre>expr ::= VISIBILE '(' expr ',' expr ')'</pre> |
| * |
| * <p>Example: return targets from the package //bar/baz that are visible to //foo. |
| * |
| * <pre> |
| * visible(//foo, //bar/baz:*) |
| * </pre> |
| */ |
| public class VisibleFunction extends FilteringQueryFunction { |
| |
| private final boolean invert; |
| |
| VisibleFunction() { |
| this(/*invert=*/ false); |
| } |
| |
| private VisibleFunction(boolean invert) { |
| this.invert = invert; |
| } |
| |
| @Override |
| public FilteringQueryFunction invert() { |
| return new VisibleFunction(!invert); |
| } |
| |
| @Override |
| public String getName() { |
| return (invert ? "no" : "") + "visible"; |
| } |
| |
| @Override |
| public int getMandatoryArguments() { |
| return 2; |
| } |
| |
| @Override |
| public int getExpressionToFilterIndex() { |
| return 1; |
| } |
| |
| @Override |
| public List<ArgumentType> getArgumentTypes() { |
| return ImmutableList.of(ArgumentType.EXPRESSION, ArgumentType.EXPRESSION); |
| } |
| |
| @Override |
| public <T> QueryTaskFuture<Void> eval( |
| final QueryEnvironment<T> env, |
| final QueryExpressionContext<T> context, |
| QueryExpression expression, |
| final List<Argument> args, |
| final Callback<T> callback) { |
| final QueryTaskFuture<ThreadSafeMutableSet<T>> toSetFuture = |
| QueryUtil.evalAll(env, context, args.get(0).getExpression()); |
| Function<ThreadSafeMutableSet<T>, QueryTaskFuture<Void>> computeVisibleNodesAsyncFunction = |
| toSet -> |
| env.eval( |
| args.get(1).getExpression(), |
| context, |
| partialResult -> { |
| for (T t : partialResult) { |
| if (invert ^ visibleToAll(env, toSet, t)) { |
| callback.process(ImmutableList.of(t)); |
| } |
| } |
| }); |
| return env.transformAsync(toSetFuture, computeVisibleNodesAsyncFunction); |
| } |
| |
| /** Returns true if {@code target} is visible to all targets in {@code toSet}. */ |
| private static <T> boolean visibleToAll(QueryEnvironment<T> env, Set<T> toSet, T target) |
| throws QueryException, InterruptedException { |
| for (T to : toSet) { |
| if (!visible(env, to, target)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** Returns true if the target {@code from} is visible to the target {@code to}. */ |
| public static <T> boolean visible(QueryEnvironment<T> env, T to, T from) |
| throws QueryException, InterruptedException { |
| Set<QueryVisibility<T>> visiblePackages = env.getAccessor().getVisibility(from); |
| for (QueryVisibility<T> spec : visiblePackages) { |
| if (spec.contains(to)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| } |