// 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.cmdline;
import com.google.common.collect.ComparisonChain;
import com.google.common.collect.Interner;
import com.google.devtools.build.lib.concurrent.BlazeInterners;
import com.google.devtools.build.lib.util.Preconditions;
import com.google.devtools.build.lib.vfs.Canonicalizer;
import com.google.devtools.build.lib.vfs.PathFragment;
import java.io.Serializable;
import java.util.Objects;
import javax.annotation.concurrent.Immutable;
/**
* Uniquely identifies a package, given a repository name and a package's path fragment.
*
* <p>The repository the build is happening in is the <i>default workspace</i>, and is identified
* by the workspace name "". Other repositories can be named in the WORKSPACE file. These
* workspaces are prefixed by {@literal @}.</p>
*/
@Immutable
public final class PackageIdentifier implements Comparable<PackageIdentifier>, Serializable {
private static final Interner<PackageIdentifier> INTERNER = BlazeInterners.newWeakInterner();
public static PackageIdentifier create(String repository, PathFragment pkgName)
throws LabelSyntaxException {
return create(RepositoryName.create(repository), pkgName);
}
public static PackageIdentifier create(RepositoryName repository, PathFragment pkgName) {
return INTERNER.intern(new PackageIdentifier(repository, pkgName));
}
public static final PackageIdentifier EMPTY_PACKAGE_ID = createInMainRepo(
PathFragment.EMPTY_FRAGMENT);
public static PackageIdentifier createInMainRepo(String name) {
return createInMainRepo(PathFragment.create(name));
}
public static PackageIdentifier createInMainRepo(PathFragment name) {
return create(RepositoryName.MAIN, name);
}
/**
* Tries to infer the package identifier from the given exec path. This method does not perform
* any I/O, but looks solely at the structure of the exec path. The resulting identifier may
* actually be a subdirectory of a package rather than a package, e.g.:
* <pre><code>
* + WORKSPACE
* + foo/BUILD
* + foo/bar/bar.java
* </code></pre>
*
* In this case, this method returns a package identifier for foo/bar, even though that is not a
* package. Callers need to look up the actual package if needed.
*
* @throws LabelSyntaxException if the exec path seems to be for an external repository that doe
* not have a valid repository name (see {@link RepositoryName#create})
*/
public static PackageIdentifier discoverFromExecPath(PathFragment execPath, boolean forFiles)
throws LabelSyntaxException {
Preconditions.checkArgument(!execPath.isAbsolute(), execPath);
PathFragment tofind = forFiles
? Preconditions.checkNotNull(
execPath.getParentDirectory(), "Must pass in files, not root directory")
: execPath;
if (tofind.startsWith(Label.EXTERNAL_PATH_PREFIX)) {
// TODO(ulfjack): Remove this when kchodorow@'s exec root rearrangement has been rolled out.
RepositoryName repository = RepositoryName.create("@" + tofind.getSegment(1));
return PackageIdentifier.create(repository, tofind.subFragment(2, tofind.segmentCount()));
} else if (!tofind.normalize().isNormalized()) {
RepositoryName repository = RepositoryName.create("@" + tofind.getSegment(1));
return PackageIdentifier.create(repository, tofind.subFragment(2, tofind.segmentCount()));
} else {
return PackageIdentifier.createInMainRepo(tofind);
}
}
/**
* The identifier for this repository. This is either "" or prefixed with an "@",
* e.g., "@myrepo".
*/
private final RepositoryName repository;
/** The name of the package. */
private final PathFragment pkgName;
/**
* Precomputed hash code. Hash/equality is based on repository and pkgName. Note that due to
* interning, x.equals(y) <=> x==y.
**/
private final int hashCode;
private PackageIdentifier(RepositoryName repository, PathFragment pkgName) {
this.repository = Preconditions.checkNotNull(repository);
this.pkgName = Canonicalizer.fragments().intern(
Preconditions.checkNotNull(pkgName).normalize());
this.hashCode = Objects.hash(repository, pkgName);
}
public static PackageIdentifier parse(String input) throws LabelSyntaxException {
String repo;
String packageName;
int packageStartPos = input.indexOf("//");
if (input.startsWith("@") && packageStartPos > 0) {
repo = input.substring(0, packageStartPos);
packageName = input.substring(packageStartPos + 2);
} else if (input.startsWith("@")) {
throw new LabelSyntaxException("starts with a '@' but does not contain '//'");
} else if (packageStartPos == 0) {
repo = RepositoryName.DEFAULT_REPOSITORY;
packageName = input.substring(2);
} else {
repo = RepositoryName.DEFAULT_REPOSITORY;
packageName = input;
}
String error = RepositoryName.validate(repo);
if (error != null) {
throw new LabelSyntaxException(error);
}
error = LabelValidator.validatePackageName(packageName);
if (error != null) {
throw new LabelSyntaxException(error);
}
return create(repo, PathFragment.create(packageName));
}
public RepositoryName getRepository() {
return repository;
}
public PathFragment getPackageFragment() {
return pkgName;
}
/**
* Returns a relative path to the source code for this package. Returns pkgName if this is in the
* main repository or external/[repository name]/[pkgName] if not.
*/
public PathFragment getSourceRoot() {
return repository.getSourceRoot().getRelative(pkgName);
}
public PathFragment getPathUnderExecRoot() {
return repository.getPathUnderExecRoot().getRelative(pkgName);
}
/**
* Returns the runfiles/execRoot path for this repository (relative to the x.runfiles/main-repo/
* directory).
*/
public PathFragment getRunfilesPath() {
return repository.getRunfilesPath().getRelative(pkgName);
}
public PackageIdentifier makeAbsolute() {
if (!repository.isDefault()) {
return this;
}
return create(RepositoryName.MAIN, pkgName);
}
/**
* Returns the name of this package.
*
* <p>There are certain places that expect the path fragment as the package name ('foo/bar') as a
* package identifier. This isn't specific enough for packages in other repositories, so their
* stringified version is '@baz//foo/bar'.</p>
*/
@Override
public String toString() {
return (repository.isDefault() || repository.isMain() ? "" : repository + "//") + pkgName;
}
@Override
public boolean equals(Object object) {
if (this == object) {
return true;
}
if (!(object instanceof PackageIdentifier)) {
return false;
}
PackageIdentifier that = (PackageIdentifier) object;
return this.hashCode == that.hashCode && pkgName.equals(that.pkgName)
&& repository.equals(that.repository);
}
@Override
public int hashCode() {
return this.hashCode;
}
@Override
public int compareTo(PackageIdentifier that) {
return ComparisonChain.start()
.compare(repository.toString(), that.repository.toString())
.compare(pkgName, that.pkgName)
.result();
}
}