1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
// 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.query2.engine;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
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.QueryFunction;
import com.google.devtools.build.lib.query2.engine.QueryEnvironment.QueryTaskFuture;
import com.google.devtools.build.lib.query2.engine.QueryEnvironment.ThreadSafeMutableSet;
import java.util.List;
/**
* A "deps" query expression, which computes the dependencies of the argument. An optional
* integer-literal second argument may be specified; its value bounds the search from the arguments.
*
* <pre>expr ::= DEPS '(' expr ')'</pre>
* <pre> | DEPS '(' expr ',' WORD ')'</pre>
*/
final class DepsFunction implements QueryFunction {
DepsFunction() {
}
@Override
public String getName() {
return "deps";
}
@Override
public int getMandatoryArguments() {
return 1; // last argument is optional
}
@Override
public List<ArgumentType> getArgumentTypes() {
return ImmutableList.of(ArgumentType.EXPRESSION, ArgumentType.INTEGER);
}
/** Breadth-first search from the arguments. */
@Override
public <T> QueryTaskFuture<Void> eval(
final QueryEnvironment<T> env,
QueryExpressionContext<T> context,
final QueryExpression expression,
List<Argument> args,
final Callback<T> callback) {
QueryExpression queryExpression = args.get(0).getExpression();
if (env instanceof StreamableQueryEnvironment && args.size() == 1) {
StreamableQueryEnvironment<T> streamableEnv = (StreamableQueryEnvironment<T>) env;
return streamableEnv.getDepsUnboundedParallel(
queryExpression,
context,
/*callback=*/ partialResult -> {
callback.process(partialResult);
ThreadSafeMutableSet<T> set = env.createThreadSafeMutableSet();
Iterables.addAll(set, partialResult);
// Ensure the proper error messages are reported.
env.buildTransitiveClosure(expression, set, /*maxDepth=*/ 1);
});
}
final int depthBound = args.size() > 1 ? args.get(1).getInteger() : Integer.MAX_VALUE;
final MinDepthUniquifier<T> minDepthUniquifier = env.createMinDepthUniquifier();
return env.eval(
queryExpression,
context,
partialResult -> {
ThreadSafeMutableSet<T> current = env.createThreadSafeMutableSet();
Iterables.addAll(current, partialResult);
env.buildTransitiveClosure(expression, current, depthBound);
// We need to iterate depthBound + 1 times.
for (int i = 0; i <= depthBound; i++) {
// Filter already visited nodes: if we see a node in a later round, then we don't need
// to
// visit it again, because the depth at which we see it at must be greater than or equal
// to the last visit.
ImmutableList<T> toProcess =
minDepthUniquifier.uniqueAtDepthLessThanOrEqualTo(current, i);
callback.process(toProcess);
current = env.createThreadSafeMutableSet();
Iterables.addAll(current, env.getFwdDeps(toProcess, context));
if (current.isEmpty()) {
// Exit when there are no more nodes to visit.
break;
}
}
});
}
}
|
