    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.codec.cli;
    018
    019import java.io.File;
    020import java.io.IOException;
    021import java.nio.charset.Charset;
    022import java.security.MessageDigest;
    023import java.util.Arrays;
    024import java.util.Locale;
    025
    026import org.apache.commons.codec.binary.Hex;
    027import org.apache.commons.codec.digest.DigestUtils;
    028import org.apache.commons.codec.digest.MessageDigestAlgorithms;
    029
    030/**
    031 * A minimal command line to run digest over files, directories or a string
    032 *
    033 * @see #main(String[])
    034 * @since 1.11
    035 */
    036public class Digest {
    037
    038    /**
    039     * Runs the digest algorithm in {@code args[0]} on the file in {@code args[1]}. If there is no {@code args[1]}, use
    040     * standard input.
    041     *
    042     * <p>
    043     * The algorithm can also be {@code ALL} or {@code *} to output one line for each known algorithm.
    044     * </p>
    045     *
    046     * @param args
    047     *            {@code args[0]} is one of {@link MessageDigestAlgorithms} name,
    048     *            {@link MessageDigest} name, {@code ALL}, or {@code *}.
    049     *            {@code args[1+]} is a FILE/DIRECTORY/String.
    050     * @throws IOException if an error occurs
    051     */
    052    public static void main(final String[] args) throws IOException {
    053        new Digest(args).run();
    054    }
    055
    056    private final String algorithm;
    057    private final String[] args;
    058    private final String[] inputs;
    059
    060    private Digest(final String[] args) {
    061        if (args == null) {
    062            throw new IllegalArgumentException("args");
    063        }
    064        if (args.length == 0) {
    065            throw new IllegalArgumentException(
    066                    String.format("Usage: java %s [algorithm] [FILE|DIRECTORY|string] ...", Digest.class.getName()));
    067        }
    068        this.args = args;
    069        algorithm = args[0];
    070        if (args.length <= 1) {
    071            inputs = null;
    072        } else {
    073            inputs = new String[args.length -1];
    074            System.arraycopy(args, 1, inputs, 0, inputs.length);
    075        }
    076    }
    077
    078    private void println(final String prefix, final byte[] digest) {
    079        println(prefix, digest, null);
    080    }
    081
    082    private void println(final String prefix, final byte[] digest, final String fileName) {
    083        // The standard appears to be to print
    084        // hex, space, then either space or '*' followed by file name
    085        // where '*' is used for binary files
    086        // shasum(1) has a -b option which generates " *" separator
    087        // we don't distinguish binary files at present
    088        System.out.println(prefix + Hex.encodeHexString(digest) + (fileName != null ? "  " + fileName : ""));
    089    }
    090
    091    private void run() throws IOException {
    092        if (algorithm.equalsIgnoreCase("ALL") || algorithm.equals("*")) {
    093            run(MessageDigestAlgorithms.values());
    094            return;
    095        }
    096        final MessageDigest messageDigest = DigestUtils.getDigest(algorithm, null);
    097        if (messageDigest != null) {
    098            run("", messageDigest);
    099        } else {
    100            run("", DigestUtils.getDigest(algorithm.toUpperCase(Locale.ROOT)));
    101        }
    102    }
    103
    104    private void run(final String[] digestAlgorithms) throws IOException {
    105        for (final String messageDigestAlgorithm : digestAlgorithms) {
    106            if (DigestUtils.isAvailable(messageDigestAlgorithm)) {
    107                run(messageDigestAlgorithm + " ", messageDigestAlgorithm);
    108            }
    109        }
    110    }
    111
    112    private void run(final String prefix, final MessageDigest messageDigest) throws IOException {
    113        if (inputs == null) {
    114            println(prefix, DigestUtils.digest(messageDigest, System.in));
    115            return;
    116        }
    117        for(final String source : inputs) {
    118            final File file = new File(source);
    119            if (file.isFile()) {
    120                println(prefix, DigestUtils.digest(messageDigest, file), source);
    121            } else if (file.isDirectory()) {
    122                final File[] listFiles = file.listFiles();
    123                if (listFiles != null) {
    124                    run(prefix, messageDigest, listFiles);
    125                }
    126            } else {
    127                // use the default charset for the command-line parameter
    128                final byte[] bytes = source.getBytes(Charset.defaultCharset());
    129                println(prefix, DigestUtils.digest(messageDigest, bytes));
    130            }
    131        }
    132    }
    133
    134    private void run(final String prefix, final MessageDigest messageDigest, final File[] files) throws IOException {
    135        for (final File file : files) {
    136            if (file.isFile()) {
    137                println(prefix, DigestUtils.digest(messageDigest, file), file.getName());
    138            }
    139        }
    140    }
    141
    142    private void run(final String prefix, final String messageDigestAlgorithm) throws IOException {
    143        run(prefix, DigestUtils.getDigest(messageDigestAlgorithm));
    144    }
    145
    146    @Override
    147    public String toString() {
    148        return String.format("%s %s", super.toString(), Arrays.toString(args));
    149    }
    150}