    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 *      https://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;
    025import java.util.Objects;
    026
    027import org.apache.commons.codec.binary.Hex;
    028import org.apache.commons.codec.digest.DigestUtils;
    029import org.apache.commons.codec.digest.MessageDigestAlgorithms;
    030
    031/**
    032 * A minimal command line to run digest over files, directories or a string.
    033 *
    034 * @see #main(String[])
    035 * @since 1.11
    036 */
    037public class Digest {
    038
    039    /**
    040     * Runs the digest algorithm in {@code args[0]} on the file in {@code args[1]}. If there is no {@code args[1]}, use
    041     * standard input.
    042     *
    043     * <p>
    044     * The algorithm can also be {@code ALL} or {@code *} to output one line for each known algorithm.
    045     * </p>
    046     *
    047     * @param args
    048     *            {@code args[0]} is one of {@link MessageDigestAlgorithms} name,
    049     *            {@link MessageDigest} name, {@code ALL}, or {@code *}.
    050     *            {@code args[1+]} is a FILE/DIRECTORY/String.
    051     * @throws IOException if an error occurs.
    052     */
    053    public static void main(final String[] args) throws IOException {
    054        new Digest(args).run();
    055    }
    056
    057    private final String algorithm;
    058    private final String[] args;
    059    private final String[] inputs;
    060
    061    private Digest(final String[] args) {
    062        Objects.requireNonNull(args);
    063        final int argsLength = args.length;
    064        if (argsLength == 0) {
    065            throw new IllegalArgumentException(
    066                    String.format("Usage: java %s [algorithm] [FILE|DIRECTORY|string] ...", Digest.class.getName()));
    067        }
    068        this.args = args;
    069        this.algorithm = args[0];
    070        if (argsLength <= 1) {
    071            this.inputs = null;
    072        } else {
    073            this.inputs = Arrays.copyOfRange(args, 1, argsLength);
    074        }
    075    }
    076
    077    private void println(final String prefix, final byte[] digest) {
    078        println(prefix, digest, null);
    079    }
    080
    081    private void println(final String prefix, final byte[] digest, final String fileName) {
    082        // The standard appears to be to print
    083        // hex, space, then either space or '*' followed by file name
    084        // where '*' is used for binary files
    085        // shasum(1) has a -b option which generates " *" separator
    086        // we don't distinguish binary files at present
    087        System.out.println(prefix + Hex.encodeHexString(digest) + (fileName != null ? "  " + fileName : ""));
    088    }
    089
    090    private void run() throws IOException {
    091        if (algorithm.equalsIgnoreCase("ALL") || algorithm.equals("*")) {
    092            run(MessageDigestAlgorithms.values());
    093            return;
    094        }
    095        final MessageDigest messageDigest = DigestUtils.getDigest(algorithm, null);
    096        if (messageDigest != null) {
    097            run("", messageDigest);
    098        } else {
    099            run("", DigestUtils.getDigest(algorithm.toUpperCase(Locale.ROOT)));
    100        }
    101    }
    102
    103    private void run(final String prefix, final MessageDigest messageDigest) throws IOException {
    104        if (inputs == null) {
    105            println(prefix, DigestUtils.digest(messageDigest, System.in));
    106            return;
    107        }
    108        for (final String source : inputs) {
    109            final File file = new File(source);
    110            if (file.isFile()) {
    111                println(prefix, DigestUtils.digest(messageDigest, file), source);
    112            } else if (file.isDirectory()) {
    113                final File[] listFiles = file.listFiles();
    114                if (listFiles != null) {
    115                    run(prefix, messageDigest, listFiles);
    116                }
    117            } else {
    118                // use the default charset for the command-line parameter
    119                final byte[] bytes = source.getBytes(Charset.defaultCharset());
    120                println(prefix, DigestUtils.digest(messageDigest, bytes));
    121            }
    122        }
    123    }
    124
    125    private void run(final String prefix, final MessageDigest messageDigest, final File[] files) throws IOException {
    126        for (final File file : files) {
    127            if (file.isFile()) {
    128                println(prefix, DigestUtils.digest(messageDigest, file), file.getName());
    129            }
    130        }
    131    }
    132
    133    private void run(final String prefix, final String messageDigestAlgorithm) throws IOException {
    134        run(prefix, DigestUtils.getDigest(messageDigestAlgorithm));
    135    }
    136
    137    private void run(final String[] digestAlgorithms) throws IOException {
    138        for (final String messageDigestAlgorithm : digestAlgorithms) {
    139            if (DigestUtils.isAvailable(messageDigestAlgorithm)) {
    140                run(messageDigestAlgorithm + " ", messageDigestAlgorithm);
    141            }
    142        }
    143    }
    144
    145    @Override
    146    public String toString() {
    147        return String.format("%s %s", super.toString(), Arrays.toString(args));
    148    }
    149}