ZipFileUtil.java

/**
 * Copyright 2008 The University of North Carolina at Chapel Hill
 *
 * 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 edu.unc.lib.dl.util;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

import org.apache.commons.compress.archivers.ArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class ZipFileUtil {
	private static final Log log = LogFactory.getLog(ZipFileUtil.class);

	/**
	 * Create a temporary directory, unzip the contents of the given zip file to
	 * it, and return the directory.
	 * 
	 * If anything goes wrong during this process, clean up the temporary
	 * directory and throw an exception.
	 */
	public static File unzipToTemp(File zipFile) throws IOException {
		// get a temporary directory to work with
		File tempDir = File.createTempFile("ingest", null);
		tempDir.delete();
		tempDir.mkdir();
		tempDir.deleteOnExit();
		log.info("Unzipping to temporary directory: " + tempDir.getPath());
		try {
			unzip(new FileInputStream(zipFile), tempDir);
			return tempDir;
		} catch (IOException e) {
			// attempt cleanup, then re-throw
			org.apache.commons.io.FileUtils.deleteDirectory(tempDir);
			throw e;
		}
	}

	/**
	 * Create a temporary directory, unzip the contents of the given zip file to
	 * it, and return the directory.
	 * 
	 * If anything goes wrong during this process, clean up the temporary
	 * directory and throw an exception.
	 */
	public static File unzipToTemp(InputStream zipStream) throws IOException {
		// get a temporary directory to work with
		File tempDir = File.createTempFile("ingest", null);
		tempDir.delete();
		tempDir.mkdir();
		tempDir.deleteOnExit();
		log.debug("Unzipping to temporary directory: " + tempDir.getPath());
		try {
			unzip(zipStream, tempDir);
			return tempDir;
		} catch (IOException e) {
			// attempt cleanup, then re-throw
			org.apache.commons.io.FileUtils.deleteDirectory(tempDir);
			throw e;
		}
	}

	/**
	 * Unzips the contents of the zip file to the directory.
	 * 
	 * If anything goes wrong during this process, clean up the temporary
	 * directory and throw an exception.
	 */
	public static void unzipToDir(File zipFile, File destDir)
			throws IOException {
		log.debug("Unzipping to directory: " + destDir.getPath());
		unzip(new FileInputStream(zipFile), destDir);
	}

	/**
	 * Unzip to the given directory, creating subdirectories as needed, and
	 * ignoring empty directories. Uses apache zip tools until java utilies are
	 * updated to support utf-8.
	 */
	public static void unzip(InputStream is, File destDir) throws IOException {
		BufferedInputStream bis = new BufferedInputStream(is);
		try (ZipArchiveInputStream zis = new ZipArchiveInputStream(bis)) {
			ArchiveEntry entry = null;
			while ((entry = zis.getNextZipEntry()) != null) {
				if (!entry.isDirectory()) {
					File f = new File(destDir, entry.getName());

					if (!isFileInsideDirectory(f, destDir)) {
						throw new IOException(
								"Attempt to write to path outside of destination directory: "
										+ entry.getName());
					}

					f.getParentFile().mkdirs();
					int count;
					byte data[] = new byte[8192];
					// write the files to the disk
					try (FileOutputStream fos = new FileOutputStream(f);
							BufferedOutputStream dest = new BufferedOutputStream(
									fos, 8192)) {
						while ((count = zis.read(data, 0, 8192)) != -1) {
							dest.write(data, 0, count);
						}
					}
				}
			}
		}
	}

	private static boolean isFileInsideDirectory(File child, File parent)
			throws IOException {

		child = child.getCanonicalFile();
		parent = parent.getCanonicalFile();

		while (child != null) {
			child = child.getParentFile();

			if (parent.equals(child))
				return true;
		}

		return false;

	}

}