| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.maven.plugins.clean; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.lang.reflect.InvocationHandler; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Proxy; |
| import java.nio.file.Files; |
| import java.nio.file.LinkOption; |
| import java.nio.file.Path; |
| import java.nio.file.StandardCopyOption; |
| import java.nio.file.attribute.BasicFileAttributes; |
| import java.util.ArrayDeque; |
| import java.util.Deque; |
| |
| import org.apache.maven.execution.ExecutionListener; |
| import org.apache.maven.execution.MavenSession; |
| import org.apache.maven.plugin.logging.Log; |
| import org.apache.maven.shared.utils.Os; |
| import org.eclipse.aether.SessionData; |
| |
| import static org.apache.maven.plugins.clean.CleanMojo.FAST_MODE_BACKGROUND; |
| import static org.apache.maven.plugins.clean.CleanMojo.FAST_MODE_DEFER; |
| |
| /** |
| * Cleans directories. |
| * |
| * @author Benjamin Bentmann |
| */ |
| class Cleaner { |
| |
| private static final boolean ON_WINDOWS = Os.isFamily(Os.FAMILY_WINDOWS); |
| |
| private static final String LAST_DIRECTORY_TO_DELETE = Cleaner.class.getName() + ".lastDirectoryToDelete"; |
| |
| /** |
| * The maven session. This is typically non-null in a real run, but it can be during unit tests. |
| */ |
| private final MavenSession session; |
| |
| private final Logger logDebug; |
| |
| private final Logger logInfo; |
| |
| private final Logger logVerbose; |
| |
| private final Logger logWarn; |
| |
| private final File fastDir; |
| |
| private final String fastMode; |
| |
| /** |
| * Creates a new cleaner. |
| * @param log The logger to use, may be <code>null</code> to disable logging. |
| * @param verbose Whether to perform verbose logging. |
| * @param fastMode The fast deletion mode |
| */ |
| Cleaner(MavenSession session, final Log log, boolean verbose, File fastDir, String fastMode) { |
| logDebug = (log == null || !log.isDebugEnabled()) ? null : log::debug; |
| |
| logInfo = (log == null || !log.isInfoEnabled()) ? null : log::info; |
| |
| logWarn = (log == null || !log.isWarnEnabled()) ? null : log::warn; |
| |
| logVerbose = verbose ? logInfo : logDebug; |
| |
| this.session = session; |
| this.fastDir = fastDir; |
| this.fastMode = fastMode; |
| } |
| |
| /** |
| * Deletes the specified directories and its contents. |
| * |
| * @param basedir The directory to delete, must not be <code>null</code>. Non-existing directories will be silently |
| * ignored. |
| * @param selector The selector used to determine what contents to delete, may be <code>null</code> to delete |
| * everything. |
| * @param followSymlinks Whether to follow symlinks. |
| * @param failOnError Whether to abort with an exception in case a selected file/directory could not be deleted. |
| * @param retryOnError Whether to undertake additional delete attempts in case the first attempt failed. |
| * @throws IOException If a file/directory could not be deleted and <code>failOnError</code> is <code>true</code>. |
| */ |
| public void delete( |
| File basedir, Selector selector, boolean followSymlinks, boolean failOnError, boolean retryOnError) |
| throws IOException { |
| if (!basedir.isDirectory()) { |
| if (!basedir.exists()) { |
| if (logDebug != null) { |
| logDebug.log("Skipping non-existing directory " + basedir); |
| } |
| return; |
| } |
| throw new IOException("Invalid base directory " + basedir); |
| } |
| |
| if (logInfo != null) { |
| logInfo.log("Deleting " + basedir + (selector != null ? " (" + selector + ")" : "")); |
| } |
| |
| File file = followSymlinks ? basedir : basedir.getCanonicalFile(); |
| |
| if (selector == null && !followSymlinks && fastDir != null && session != null) { |
| // If anything wrong happens, we'll just use the usual deletion mechanism |
| if (fastDelete(file)) { |
| return; |
| } |
| } |
| |
| delete(file, "", selector, followSymlinks, failOnError, retryOnError); |
| } |
| |
| private boolean fastDelete(File baseDirFile) { |
| Path baseDir = baseDirFile.toPath(); |
| Path fastDir = this.fastDir.toPath(); |
| // Handle the case where we use ${maven.multiModuleProjectDirectory}/target/.clean for example |
| if (fastDir.toAbsolutePath().startsWith(baseDir.toAbsolutePath())) { |
| try { |
| String prefix = baseDir.getFileName().toString() + "."; |
| Path tmpDir = Files.createTempDirectory(baseDir.getParent(), prefix); |
| try { |
| Files.move(baseDir, tmpDir, StandardCopyOption.REPLACE_EXISTING); |
| if (session != null) { |
| session.getRepositorySession().getData().set(LAST_DIRECTORY_TO_DELETE, baseDir.toFile()); |
| } |
| baseDir = tmpDir; |
| } catch (IOException e) { |
| Files.delete(tmpDir); |
| throw e; |
| } |
| } catch (IOException e) { |
| if (logDebug != null) { |
| // TODO: this Logger interface cannot log exceptions and needs refactoring |
| logDebug.log("Unable to fast delete directory: " + e); |
| } |
| return false; |
| } |
| } |
| // Create fastDir and the needed parents if needed |
| try { |
| if (!Files.isDirectory(fastDir)) { |
| Files.createDirectories(fastDir); |
| } |
| } catch (IOException e) { |
| if (logDebug != null) { |
| // TODO: this Logger interface cannot log exceptions and needs refactoring |
| logDebug.log("Unable to fast delete directory as the path " + fastDir |
| + " does not point to a directory or cannot be created: " + e); |
| } |
| return false; |
| } |
| |
| try { |
| Path tmpDir = Files.createTempDirectory(fastDir, ""); |
| Path dstDir = tmpDir.resolve(baseDir.getFileName()); |
| // Note that by specifying the ATOMIC_MOVE, we expect an exception to be thrown |
| // if the path leads to a directory on another mountpoint. If this is the case |
| // or any other exception occurs, an exception will be thrown in which case |
| // the method will return false and the usual deletion will be performed. |
| Files.move(baseDir, dstDir, StandardCopyOption.ATOMIC_MOVE); |
| BackgroundCleaner.delete(this, tmpDir.toFile(), fastMode); |
| return true; |
| } catch (IOException e) { |
| if (logDebug != null) { |
| // TODO: this Logger interface cannot log exceptions and needs refactoring |
| logDebug.log("Unable to fast delete directory: " + e); |
| } |
| return false; |
| } |
| } |
| |
| /** |
| * Deletes the specified file or directory. |
| * |
| * @param file The file/directory to delete, must not be <code>null</code>. If <code>followSymlinks</code> is |
| * <code>false</code>, it is assumed that the parent file is canonical. |
| * @param pathname The relative pathname of the file, using {@link File#separatorChar}, must not be |
| * <code>null</code>. |
| * @param selector The selector used to determine what contents to delete, may be <code>null</code> to delete |
| * everything. |
| * @param followSymlinks Whether to follow symlinks. |
| * @param failOnError Whether to abort with an exception in case a selected file/directory could not be deleted. |
| * @param retryOnError Whether to undertake additional delete attempts in case the first attempt failed. |
| * @return The result of the cleaning, never <code>null</code>. |
| * @throws IOException If a file/directory could not be deleted and <code>failOnError</code> is <code>true</code>. |
| */ |
| private Result delete( |
| File file, |
| String pathname, |
| Selector selector, |
| boolean followSymlinks, |
| boolean failOnError, |
| boolean retryOnError) |
| throws IOException { |
| Result result = new Result(); |
| |
| boolean isDirectory = file.isDirectory(); |
| |
| if (isDirectory) { |
| if (selector == null || selector.couldHoldSelected(pathname)) { |
| if (followSymlinks || !isSymbolicLink(file.toPath())) { |
| File canonical = followSymlinks ? file : file.getCanonicalFile(); |
| String[] filenames = canonical.list(); |
| if (filenames != null) { |
| String prefix = pathname.length() > 0 ? pathname + File.separatorChar : ""; |
| for (int i = filenames.length - 1; i >= 0; i--) { |
| String filename = filenames[i]; |
| File child = new File(canonical, filename); |
| result.update(delete( |
| child, prefix + filename, selector, followSymlinks, failOnError, retryOnError)); |
| } |
| } |
| } else if (logDebug != null) { |
| logDebug.log("Not recursing into symlink " + file); |
| } |
| } else if (logDebug != null) { |
| logDebug.log("Not recursing into directory without included files " + file); |
| } |
| } |
| |
| if (!result.excluded && (selector == null || selector.isSelected(pathname))) { |
| if (logVerbose != null) { |
| if (isDirectory) { |
| logVerbose.log("Deleting directory " + file); |
| } else if (file.exists()) { |
| logVerbose.log("Deleting file " + file); |
| } else { |
| logVerbose.log("Deleting dangling symlink " + file); |
| } |
| } |
| result.failures += delete(file, failOnError, retryOnError); |
| } else { |
| result.excluded = true; |
| } |
| |
| return result; |
| } |
| |
| private boolean isSymbolicLink(Path path) throws IOException { |
| BasicFileAttributes attrs = Files.readAttributes(path, BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS); |
| return attrs.isSymbolicLink() |
| // MCLEAN-93: NTFS junctions have isDirectory() and isOther() attributes set |
| || (attrs.isDirectory() && attrs.isOther()); |
| } |
| |
| /** |
| * Deletes the specified file, directory. If the path denotes a symlink, only the link is removed, its target is |
| * left untouched. |
| * |
| * @param file The file/directory to delete, must not be <code>null</code>. |
| * @param failOnError Whether to abort with an exception in case the file/directory could not be deleted. |
| * @param retryOnError Whether to undertake additional delete attempts in case the first attempt failed. |
| * @return <code>0</code> if the file was deleted, <code>1</code> otherwise. |
| * @throws IOException If a file/directory could not be deleted and <code>failOnError</code> is <code>true</code>. |
| */ |
| private int delete(File file, boolean failOnError, boolean retryOnError) throws IOException { |
| if (!file.delete()) { |
| boolean deleted = false; |
| |
| if (retryOnError) { |
| if (ON_WINDOWS) { |
| // try to release any locks held by non-closed files |
| System.gc(); |
| } |
| |
| final int[] delays = {50, 250, 750}; |
| for (int i = 0; !deleted && i < delays.length; i++) { |
| try { |
| Thread.sleep(delays[i]); |
| } catch (InterruptedException e) { |
| // ignore |
| } |
| deleted = file.delete() || !file.exists(); |
| } |
| } else { |
| deleted = !file.exists(); |
| } |
| |
| if (!deleted) { |
| if (failOnError) { |
| throw new IOException("Failed to delete " + file); |
| } else { |
| if (logWarn != null) { |
| logWarn.log("Failed to delete " + file); |
| } |
| return 1; |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| private static class Result { |
| |
| private int failures; |
| |
| private boolean excluded; |
| |
| public void update(Result result) { |
| failures += result.failures; |
| excluded |= result.excluded; |
| } |
| } |
| |
| private interface Logger { |
| |
| void log(CharSequence message); |
| } |
| |
| private static class BackgroundCleaner extends Thread { |
| |
| private static BackgroundCleaner instance; |
| |
| private final Deque<File> filesToDelete = new ArrayDeque<>(); |
| |
| private final Cleaner cleaner; |
| |
| private final String fastMode; |
| |
| private static final int NEW = 0; |
| private static final int RUNNING = 1; |
| private static final int STOPPED = 2; |
| |
| private int status = NEW; |
| |
| public static void delete(Cleaner cleaner, File dir, String fastMode) { |
| synchronized (BackgroundCleaner.class) { |
| if (instance == null || !instance.doDelete(dir)) { |
| instance = new BackgroundCleaner(cleaner, dir, fastMode); |
| } |
| } |
| } |
| |
| static void sessionEnd() { |
| synchronized (BackgroundCleaner.class) { |
| if (instance != null) { |
| instance.doSessionEnd(); |
| } |
| } |
| } |
| |
| private BackgroundCleaner(Cleaner cleaner, File dir, String fastMode) { |
| super("mvn-background-cleaner"); |
| this.cleaner = cleaner; |
| this.fastMode = fastMode; |
| init(cleaner.fastDir, dir); |
| } |
| |
| public void run() { |
| while (true) { |
| File basedir = pollNext(); |
| if (basedir == null) { |
| break; |
| } |
| try { |
| cleaner.delete(basedir, "", null, false, false, true); |
| } catch (IOException e) { |
| // do not display errors |
| } |
| } |
| } |
| |
| synchronized void init(File fastDir, File dir) { |
| if (fastDir.isDirectory()) { |
| File[] children = fastDir.listFiles(); |
| if (children != null && children.length > 0) { |
| for (File child : children) { |
| doDelete(child); |
| } |
| } |
| } |
| doDelete(dir); |
| } |
| |
| synchronized File pollNext() { |
| File basedir = filesToDelete.poll(); |
| if (basedir == null) { |
| if (cleaner.session != null) { |
| SessionData data = cleaner.session.getRepositorySession().getData(); |
| File lastDir = (File) data.get(LAST_DIRECTORY_TO_DELETE); |
| if (lastDir != null) { |
| data.set(LAST_DIRECTORY_TO_DELETE, null); |
| return lastDir; |
| } |
| } |
| status = STOPPED; |
| notifyAll(); |
| } |
| return basedir; |
| } |
| |
| synchronized boolean doDelete(File dir) { |
| if (status == STOPPED) { |
| return false; |
| } |
| filesToDelete.add(dir); |
| if (status == NEW && FAST_MODE_BACKGROUND.equals(fastMode)) { |
| status = RUNNING; |
| notifyAll(); |
| start(); |
| } |
| wrapExecutionListener(); |
| return true; |
| } |
| |
| /** |
| * If this has not been done already, we wrap the ExecutionListener inside a proxy |
| * which simply delegates call to the previous listener. When the session ends, it will |
| * also call {@link BackgroundCleaner#sessionEnd()}. |
| * There's no clean API to do that properly as this is a very unusual use case for a plugin |
| * to outlive its main execution. |
| */ |
| private void wrapExecutionListener() { |
| ExecutionListener executionListener = cleaner.session.getRequest().getExecutionListener(); |
| if (executionListener == null |
| || !Proxy.isProxyClass(executionListener.getClass()) |
| || !(Proxy.getInvocationHandler(executionListener) instanceof SpyInvocationHandler)) { |
| ExecutionListener listener = (ExecutionListener) Proxy.newProxyInstance( |
| ExecutionListener.class.getClassLoader(), |
| new Class[] {ExecutionListener.class}, |
| new SpyInvocationHandler(executionListener)); |
| cleaner.session.getRequest().setExecutionListener(listener); |
| } |
| } |
| |
| synchronized void doSessionEnd() { |
| if (status != STOPPED) { |
| if (status == NEW) { |
| start(); |
| } |
| if (!FAST_MODE_DEFER.equals(fastMode)) { |
| try { |
| if (cleaner.logInfo != null) { |
| cleaner.logInfo.log("Waiting for background file deletion"); |
| } |
| while (status != STOPPED) { |
| wait(); |
| } |
| } catch (InterruptedException e) { |
| // ignore |
| } |
| } |
| } |
| } |
| } |
| |
| static class SpyInvocationHandler implements InvocationHandler { |
| private final ExecutionListener delegate; |
| |
| SpyInvocationHandler(ExecutionListener delegate) { |
| this.delegate = delegate; |
| } |
| |
| @Override |
| public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { |
| if ("sessionEnded".equals(method.getName())) { |
| BackgroundCleaner.sessionEnd(); |
| } |
| if (delegate != null) { |
| return method.invoke(delegate, args); |
| } |
| return null; |
| } |
| } |
| } |