    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one
    003 * or more contributor license agreements.  See the NOTICE file
    004 * distributed with this work for additional information
    005 * regarding copyright ownership.  The ASF licenses this file
    006 * to you under the Apache License, Version 2.0 (the
    007 * "License"); you may not use this file except in compliance
    008 * with the License.  You may obtain a copy of the License at
    009 *
    010 * http://www.apache.org/licenses/LICENSE-2.0
    011 *
    012 * Unless required by applicable law or agreed to in writing,
    013 * software distributed under the License is distributed on an
    014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    015 * KIND, either express or implied.  See the License for the
    016 * specific language governing permissions and limitations
    017 * under the License.
    018 */
    019package org.apache.commons.compress.archivers.ar;
    020
    021import java.io.File;
    022import java.io.IOException;
    023import java.nio.file.Files;
    024import java.nio.file.LinkOption;
    025import java.nio.file.Path;
    026import java.util.Date;
    027import java.util.Objects;
    028
    029import org.apache.commons.compress.archivers.ArchiveEntry;
    030
    031/**
    032 * Represents an archive entry in the "ar" format.
    033 *
    034 * Each AR archive starts with "!&lt;arch&gt;" followed by a LF. After these 8 bytes
    035 * the archive entries are listed. The format of an entry header is as it follows:
    036 *
    037 * <pre>
    038 * START BYTE   END BYTE    NAME                    FORMAT      LENGTH
    039 * 0            15          File name               ASCII       16
    040 * 16           27          Modification timestamp  Decimal     12
    041 * 28           33          Owner ID                Decimal     6
    042 * 34           39          Group ID                Decimal     6
    043 * 40           47          File mode               Octal       8
    044 * 48           57          File size (bytes)       Decimal     10
    045 * 58           59          File magic              \140\012    2
    046 * </pre>
    047 *
    048 * This specifies that an ar archive entry header contains 60 bytes.
    049 *
    050 * Due to the limitation of the file name length to 16 bytes GNU and
    051 * BSD has their own variants of this format. Currently Commons
    052 * Compress can read but not write the GNU variant.  It fully supports
    053 * the BSD variant.
    054 *
    055 * @see <a href="https://www.freebsd.org/cgi/man.cgi?query=ar&sektion=5">ar man page</a>
    056 *
    057 * @Immutable
    058 */
    059public class ArArchiveEntry implements ArchiveEntry {
    060
    061    /** The header for each entry */
    062    public static final String HEADER = "!<arch>\n";
    063
    064    /** The trailer for each entry */
    065    public static final String TRAILER = "`\012";
    066
    067    private static final int DEFAULT_MODE = 33188; // = (octal) 0100644
    068    /**
    069     * SVR4/GNU adds a trailing / to names; BSD does not.
    070     * They also vary in how names longer than 16 characters are represented.
    071     * (Not yet fully supported by this implementation)
    072     */
    073    private final String name;
    074    private final int userId;
    075    private final int groupId;
    076    private final int mode;
    077    private final long lastModified;
    078    private final long length;
    079
    080    /**
    081     * Creates a new instance using the attributes of the given file
    082     * @param inputFile the file to create an entry from
    083     * @param entryName the name of the entry
    084     */
    085    public ArArchiveEntry(final File inputFile, final String entryName) {
    086        // TODO sort out mode
    087        this(entryName, inputFile.isFile() ? inputFile.length() : 0,
    088             0, 0, DEFAULT_MODE, inputFile.lastModified() / 1000);
    089    }
    090
    091    /**
    092     * Creates a new instance using the attributes of the given file
    093     * @param inputPath the file to create an entry from
    094     * @param entryName the name of the entry
    095     * @param options options indicating how symbolic links are handled.
    096     * @throws IOException if an I/O error occurs.
    097     * @since 1.21
    098     */
    099    public ArArchiveEntry(final Path inputPath, final String entryName, final LinkOption... options) throws IOException {
    100        this(entryName, Files.isRegularFile(inputPath, options) ? Files.size(inputPath) : 0, 0, 0, DEFAULT_MODE,
    101            Files.getLastModifiedTime(inputPath, options).toMillis() / 1000);
    102    }
    103
    104    /**
    105     * Create a new instance using a couple of default values.
    106     *
    107     * <p>Sets userId and groupId to 0, the octal file mode to 644 and
    108     * the last modified time to the current time.</p>
    109     *
    110     * @param name name of the entry
    111     * @param length length of the entry in bytes
    112     */
    113    public ArArchiveEntry(final String name, final long length) {
    114        this(name, length, 0, 0, DEFAULT_MODE,
    115             System.currentTimeMillis() / 1000);
    116    }
    117
    118    /**
    119     * Create a new instance.
    120     *
    121     * @param name name of the entry
    122     * @param length length of the entry in bytes
    123     * @param userId numeric user id
    124     * @param groupId numeric group id
    125     * @param mode file mode
    126     * @param lastModified last modified time in seconds since the epoch
    127     */
    128    public ArArchiveEntry(final String name, final long length, final int userId, final int groupId,
    129                          final int mode, final long lastModified) {
    130        this.name = name;
    131        if (length < 0) {
    132            throw new IllegalArgumentException("length must not be negative");
    133        }
    134        this.length = length;
    135        this.userId = userId;
    136        this.groupId = groupId;
    137        this.mode = mode;
    138        this.lastModified = lastModified;
    139    }
    140
    141    @Override
    142    public boolean equals(final Object obj) {
    143        if (this == obj) {
    144            return true;
    145        }
    146        if (obj == null || getClass() != obj.getClass()) {
    147            return false;
    148        }
    149        final ArArchiveEntry other = (ArArchiveEntry) obj;
    150        if (name == null) {
    151            return other.name == null;
    152        }
    153        return name.equals(other.name);
    154    }
    155
    156    public int getGroupId() {
    157        return groupId;
    158    }
    159
    160    /**
    161     * Last modified time in seconds since the epoch.
    162     * @return the last modified date
    163     */
    164    public long getLastModified() {
    165        return lastModified;
    166    }
    167
    168    @Override
    169    public Date getLastModifiedDate() {
    170        return new Date(1000 * getLastModified());
    171    }
    172
    173    public long getLength() {
    174        return length;
    175    }
    176
    177    public int getMode() {
    178        return mode;
    179    }
    180
    181    @Override
    182    public String getName() {
    183        return name;
    184    }
    185
    186    @Override
    187    public long getSize() {
    188        return this.getLength();
    189    }
    190
    191    public int getUserId() {
    192        return userId;
    193    }
    194
    195    @Override
    196    public int hashCode() {
    197        return Objects.hash(name);
    198    }
    199
    200    @Override
    201    public boolean isDirectory() {
    202        return false;
    203    }
    204}