// 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.analysis.config;
import com.google.devtools.build.lib.analysis.BlazeDirectories;
import com.google.devtools.build.lib.analysis.config.BuildConfiguration.Fragment;
import com.google.devtools.build.lib.cmdline.Label;
import com.google.devtools.build.lib.events.EventHandler;
import com.google.devtools.build.lib.packages.NoSuchPackageException;
import com.google.devtools.build.lib.packages.NoSuchTargetException;
import com.google.devtools.build.lib.packages.Package;
import com.google.devtools.build.lib.packages.Target;
import com.google.devtools.build.lib.pkgcache.LoadedPackageProvider;
import com.google.devtools.build.lib.pkgcache.PackageProvider;
import com.google.devtools.build.lib.pkgcache.TargetProvider;
import com.google.devtools.build.lib.vfs.Path;
import javax.annotation.Nullable;
/**
* An environment to support creating BuildConfiguration instances in a hermetic fashion; all
* accesses to packages or the file system must go through this interface, so that they can
* be recorded for correct caching.
*/
public interface ConfigurationEnvironment {
/**
* Returns an event handler to report errors to. Note that reporting an error does not cause the
* computation to abort - you also need to throw an exception.
*/
EventHandler getEventHandler();
/**
* Returns a target for the given label, loading it if necessary, and throwing an exception if it
* does not exist.
*
* @see TargetProvider#getTarget
*/
Target getTarget(Label label) throws NoSuchPackageException, NoSuchTargetException;
/** Returns a path for the given file within the given package. */
Path getPath(Package pkg, String fileName);
/** Returns fragment based on fragment class and build options. */
T getFragment(BuildOptions buildOptions, Class fragmentType)
throws InvalidConfigurationException;
/** Returns global value of BlazeDirectories. */
@Nullable
BlazeDirectories getBlazeDirectories();
/**
* An implementation backed by a {@link PackageProvider} instance.
*/
public static final class TargetProviderEnvironment implements ConfigurationEnvironment {
private final LoadedPackageProvider packageProvider;
private final BlazeDirectories blazeDirectories;
public TargetProviderEnvironment(PackageProvider packageProvider,
EventHandler eventHandler, BlazeDirectories blazeDirectories) {
this.packageProvider = new LoadedPackageProvider(packageProvider, eventHandler);
this.blazeDirectories = blazeDirectories;
}
public TargetProviderEnvironment(PackageProvider packageProvider,
EventHandler eventHandler) {
this(packageProvider, eventHandler, null);
}
@Override
public EventHandler getEventHandler() {
return packageProvider.getEventHandler();
}
@Override
public Target getTarget(final Label label)
throws NoSuchPackageException, NoSuchTargetException {
return packageProvider.getLoadedTarget(label);
}
@Override
public Path getPath(Package pkg, String fileName) {
return pkg.getPackageDirectory().getRelative(fileName);
}
@Override
public T getFragment(BuildOptions buildOptions, Class fragmentType) {
throw new UnsupportedOperationException();
}
@Override
public BlazeDirectories getBlazeDirectories() {
return blazeDirectories;
}
}
}