// Copyright 2017 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.rules.platform;
import com.google.common.base.Function;
import com.google.common.collect.Iterables;
import com.google.devtools.build.lib.analysis.ConfiguredTarget;
import com.google.devtools.build.lib.analysis.FileProvider;
import com.google.devtools.build.lib.analysis.FilesToRunProvider;
import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
import com.google.devtools.build.lib.analysis.RuleContext;
import com.google.devtools.build.lib.analysis.RunfilesProvider;
import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
import com.google.devtools.build.lib.analysis.platform.ConstraintValueInfo;
import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
import com.google.devtools.build.lib.syntax.Type;
import com.google.devtools.build.lib.util.CPU;
import com.google.devtools.build.lib.util.OS;
import com.google.devtools.build.lib.util.Preconditions;
import java.util.Map;
/** Defines a platform for execution contexts. */
public class Platform implements RuleConfiguredTargetFactory {
@Override
public ConfiguredTarget create(RuleContext ruleContext)
throws InterruptedException, RuleErrorException {
PlatformInfo.Builder platformBuilder = PlatformInfo.builder();
if (ruleContext.attributes().get(PlatformRule.HOST_PLATFORM_ATTR, Type.BOOLEAN)) {
// Create default constraints based on the current OS and CPU values.
autodetectHostConstraints(ruleContext, platformBuilder);
} else {
platformBuilder.addConstraints(
ConstraintValue.constraintValues(
ruleContext.getPrerequisites(PlatformRule.CONSTRAINT_VALUES_ATTR, Mode.DONT_CHECK)));
}
Map<String, String> remoteExecutionProperties =
ruleContext.attributes().get(PlatformRule.REMOTE_EXECUTION_PROPS_ATTR, Type.STRING_DICT);
platformBuilder.addRemoteExecutionProperties(remoteExecutionProperties);
PlatformInfo platformInfo;
try {
platformInfo = platformBuilder.build();
} catch (PlatformInfo.DuplicateConstraintException e) {
// Report the error and return null.
ruleContext.attributeError(PlatformRule.CONSTRAINT_VALUES_ATTR, e.getMessage());
return null;
}
return new RuleConfiguredTargetBuilder(ruleContext)
.addProvider(RunfilesProvider.class, RunfilesProvider.EMPTY)
.addProvider(FileProvider.class, FileProvider.EMPTY)
.addProvider(FilesToRunProvider.class, FilesToRunProvider.EMPTY)
.addNativeDeclaredProvider(platformInfo)
.build();
}
private void autodetectHostConstraints(
RuleContext ruleContext, PlatformInfo.Builder platformBuilder) {
// Add the CPU.
CPU cpu = CPU.getCurrent();
Iterable<ConstraintValueInfo> cpuConstraintValues =
ConstraintValue.constraintValues(
ruleContext.getPrerequisites(PlatformRule.HOST_CPU_CONSTRAINTS_ATTR, Mode.DONT_CHECK));
for (ConstraintValueInfo constraint : cpuConstraintValues) {
if (cpu.getCanonicalName().equals(constraint.label().getName())) {
platformBuilder.addConstraint(constraint);
break;
}
}
// Add the OS.
OS os = OS.getCurrent();
Iterable<ConstraintValueInfo> osConstraintValues =
ConstraintValue.constraintValues(
ruleContext.getPrerequisites(PlatformRule.HOST_OS_CONSTRAINTS_ATTR, Mode.DONT_CHECK));
for (ConstraintValueInfo constraint : osConstraintValues) {
if (os.getCanonicalName().equals(constraint.label().getName())) {
platformBuilder.addConstraint(constraint);
break;
}
}
}
/** Retrieves and casts the provider from the given target. */
public static PlatformInfo platform(TransitiveInfoCollection target) {
Object provider = target.get(PlatformInfo.SKYLARK_IDENTIFIER);
if (provider == null) {
return null;
}
Preconditions.checkState(provider instanceof PlatformInfo);
return (PlatformInfo) provider;
}
/** Retrieves and casts the providers from the given targets. */
public static Iterable<PlatformInfo> platforms(
Iterable<? extends TransitiveInfoCollection> targets) {
return Iterables.transform(
targets,
new Function<TransitiveInfoCollection, PlatformInfo>() {
@Override
public PlatformInfo apply(TransitiveInfoCollection target) {
return platform(target);
}
});
}
}