    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.compress.archivers.zip;
    018
    019import java.io.BufferedInputStream;
    020import java.io.ByteArrayInputStream;
    021import java.io.Closeable;
    022import java.io.EOFException;
    023import java.io.File;
    024import java.io.IOException;
    025import java.io.InputStream;
    026import java.io.SequenceInputStream;
    027import java.nio.ByteBuffer;
    028import java.nio.ByteOrder;
    029import java.nio.channels.FileChannel;
    030import java.nio.channels.SeekableByteChannel;
    031import java.nio.charset.Charset;
    032import java.nio.charset.StandardCharsets;
    033import java.nio.file.Files;
    034import java.nio.file.OpenOption;
    035import java.nio.file.Path;
    036import java.nio.file.StandardOpenOption;
    037import java.util.ArrayList;
    038import java.util.Arrays;
    039import java.util.Collections;
    040import java.util.Comparator;
    041import java.util.EnumSet;
    042import java.util.Enumeration;
    043import java.util.HashMap;
    044import java.util.LinkedList;
    045import java.util.List;
    046import java.util.Map;
    047import java.util.Objects;
    048import java.util.stream.Collectors;
    049import java.util.stream.IntStream;
    050import java.util.zip.Inflater;
    051import java.util.zip.ZipException;
    052
    053import org.apache.commons.compress.archivers.EntryStreamOffsets;
    054import org.apache.commons.compress.compressors.bzip2.BZip2CompressorInputStream;
    055import org.apache.commons.compress.compressors.deflate64.Deflate64CompressorInputStream;
    056import org.apache.commons.compress.utils.BoundedArchiveInputStream;
    057import org.apache.commons.compress.utils.BoundedSeekableByteChannelInputStream;
    058import org.apache.commons.compress.utils.IOUtils;
    059import org.apache.commons.compress.utils.InputStreamStatistics;
    060import org.apache.commons.compress.utils.SeekableInMemoryByteChannel;
    061import org.apache.commons.io.Charsets;
    062import org.apache.commons.io.FilenameUtils;
    063import org.apache.commons.io.build.AbstractOrigin.ByteArrayOrigin;
    064import org.apache.commons.io.build.AbstractStreamBuilder;
    065import org.apache.commons.io.input.BoundedInputStream;
    066
    067/**
    068 * Replacement for {@link java.util.zip.ZipFile}.
    069 * <p>
    070 * This class adds support for file name encodings other than UTF-8 (which is required to work on ZIP files created by native ZIP tools and is able to skip a
    071 * preamble like the one found in self extracting archives. Furthermore it returns instances of
    072 * {@code org.apache.commons.compress.archivers.zip.ZipArchiveEntry} instead of {@link java.util.zip.ZipEntry}.
    073 * </p>
    074 * <p>
    075 * It doesn't extend {@link java.util.zip.ZipFile} as it would have to reimplement all methods anyway. Like {@link java.util.zip.ZipFile}, it uses
    076 * SeekableByteChannel under the covers and supports compressed and uncompressed entries. As of Apache Commons Compress 1.3 it also transparently supports Zip64
    077 * extensions and thus individual entries and archives larger than 4 GB or with more than 65,536 entries.
    078 * </p>
    079 * <p>
    080 * The method signatures mimic the ones of {@link java.util.zip.ZipFile}, with a couple of exceptions:
    081 * </p>
    082 * <ul>
    083 * <li>There is no getName method.</li>
    084 * <li>entries has been renamed to getEntries.</li>
    085 * <li>getEntries and getEntry return {@code org.apache.commons.compress.archivers.zip.ZipArchiveEntry} instances.</li>
    086 * <li>close is allowed to throw IOException.</li>
    087 * </ul>
    088 */
    089public class ZipFile implements Closeable {
    090
    091    /**
    092     * Lock-free implementation of BoundedInputStream. The implementation uses positioned reads on the underlying archive file channel and therefore performs
    093     * significantly faster in concurrent environment.
    094     */
    095    private static class BoundedFileChannelInputStream extends BoundedArchiveInputStream {
    096        private final FileChannel archive;
    097
    098        BoundedFileChannelInputStream(final long start, final long remaining, final FileChannel archive) {
    099            super(start, remaining);
    100            this.archive = archive;
    101        }
    102
    103        @Override
    104        protected int read(final long pos, final ByteBuffer buf) throws IOException {
    105            final int read = archive.read(buf, pos);
    106            buf.flip();
    107            return read;
    108        }
    109    }
    110
    111    /**
    112     * Builds new {@link ZipFile} instances.
    113     * <p>
    114     * The channel will be opened for reading, assuming the specified encoding for file names.
    115     * </p>
    116     * <p>
    117     * See {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} to read from an in-memory archive.
    118     * </p>
    119     * <p>
    120     * By default the central directory record and all local file headers of the archive will be read immediately which may take a considerable amount of time
    121     * when the archive is big. The {@code ignoreLocalFileHeader} parameter can be set to {@code true} which restricts parsing to the central directory.
    122     * Unfortunately the local file header may contain information not present inside of the central directory which will not be available when the argument is
    123     * set to {@code true}. This includes the content of the Unicode extra field, so setting {@code
    124     * ignoreLocalFileHeader} to {@code true} means {@code useUnicodeExtraFields} will be ignored effectively.
    125     * </p>
    126     *
    127     * @since 1.26.0
    128     */
    129    public static class Builder extends AbstractStreamBuilder<ZipFile, Builder> {
    130
    131        static final Charset DEFAULT_CHARSET = StandardCharsets.UTF_8;
    132
    133        private SeekableByteChannel seekableByteChannel;
    134        private boolean useUnicodeExtraFields = true;
    135        private boolean ignoreLocalFileHeader;
    136        private long maxNumberOfDisks = 1;
    137
    138        public Builder() {
    139            setCharset(DEFAULT_CHARSET);
    140            setCharsetDefault(DEFAULT_CHARSET);
    141        }
    142
    143        @Override
    144        public ZipFile get() throws IOException {
    145            final SeekableByteChannel actualChannel;
    146            final String actualDescription;
    147            if (seekableByteChannel != null) {
    148                actualChannel = seekableByteChannel;
    149                actualDescription = actualChannel.getClass().getSimpleName();
    150            } else if (checkOrigin() instanceof ByteArrayOrigin) {
    151                actualChannel = new SeekableInMemoryByteChannel(checkOrigin().getByteArray());
    152                actualDescription = actualChannel.getClass().getSimpleName();
    153            } else {
    154                OpenOption[] openOptions = getOpenOptions();
    155                if (openOptions.length == 0) {
    156                    openOptions = new OpenOption[] { StandardOpenOption.READ };
    157                }
    158                final Path path = getPath();
    159                actualChannel = openZipChannel(path, maxNumberOfDisks, openOptions);
    160                actualDescription = path.toString();
    161            }
    162            final boolean closeOnError = seekableByteChannel != null;
    163            return new ZipFile(actualChannel, actualDescription, getCharset(), useUnicodeExtraFields, closeOnError, ignoreLocalFileHeader);
    164        }
    165
    166        /**
    167         * Sets whether to ignore information stored inside the local file header.
    168         *
    169         * @param ignoreLocalFileHeader whether to ignore information stored inside.
    170         * @return {@code this} instance.
    171         */
    172        public Builder setIgnoreLocalFileHeader(final boolean ignoreLocalFileHeader) {
    173            this.ignoreLocalFileHeader = ignoreLocalFileHeader;
    174            return this;
    175        }
    176
    177        /**
    178         * Sets max number of multi archive disks, default is 1 (no multi archive).
    179         *
    180         * @param maxNumberOfDisks max number of multi archive disks.
    181         *
    182         * @return {@code this} instance.
    183         */
    184        public Builder setMaxNumberOfDisks(final long maxNumberOfDisks) {
    185            this.maxNumberOfDisks = maxNumberOfDisks;
    186            return this;
    187        }
    188
    189        /**
    190         * The actual channel, overrides any other input aspects like a File, Path, and so on.
    191         *
    192         * @param seekableByteChannel The actual channel.
    193         * @return {@code this} instance.
    194         */
    195        public Builder setSeekableByteChannel(final SeekableByteChannel seekableByteChannel) {
    196            this.seekableByteChannel = seekableByteChannel;
    197            return this;
    198        }
    199
    200        /**
    201         * Sets whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    202         *
    203         * @param useUnicodeExtraFields whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    204         * @return {@code this} instance.
    205         */
    206        public Builder setUseUnicodeExtraFields(final boolean useUnicodeExtraFields) {
    207            this.useUnicodeExtraFields = useUnicodeExtraFields;
    208            return this;
    209        }
    210
    211    }
    212
    213    /**
    214     * Extends ZipArchiveEntry to store the offset within the archive.
    215     */
    216    private static final class Entry extends ZipArchiveEntry {
    217
    218        @Override
    219        public boolean equals(final Object other) {
    220            if (super.equals(other)) {
    221                // super.equals would return false if other were not an Entry
    222                final Entry otherEntry = (Entry) other;
    223                return getLocalHeaderOffset() == otherEntry.getLocalHeaderOffset() && super.getDataOffset() == otherEntry.getDataOffset()
    224                        && super.getDiskNumberStart() == otherEntry.getDiskNumberStart();
    225            }
    226            return false;
    227        }
    228
    229        @Override
    230        public int hashCode() {
    231            return 3 * super.hashCode() + (int) getLocalHeaderOffset() + (int) (getLocalHeaderOffset() >> 32);
    232        }
    233    }
    234
    235    private static final class NameAndComment {
    236        private final byte[] name;
    237        private final byte[] comment;
    238
    239        private NameAndComment(final byte[] name, final byte[] comment) {
    240            this.name = name;
    241            this.comment = comment;
    242        }
    243    }
    244
    245    private static final class StoredStatisticsStream extends BoundedInputStream implements InputStreamStatistics {
    246        StoredStatisticsStream(final InputStream in) {
    247            super(in);
    248        }
    249
    250        @Override
    251        public long getCompressedCount() {
    252            return super.getCount();
    253        }
    254
    255        @Override
    256        public long getUncompressedCount() {
    257            return getCompressedCount();
    258        }
    259    }
    260
    261    private static final String DEFAULT_CHARSET_NAME = StandardCharsets.UTF_8.name();
    262
    263    private static final EnumSet<StandardOpenOption> READ = EnumSet.of(StandardOpenOption.READ);
    264
    265    private static final int HASH_SIZE = 509;
    266    static final int NIBLET_MASK = 0x0f;
    267    static final int BYTE_SHIFT = 8;
    268    private static final int POS_0 = 0;
    269    private static final int POS_1 = 1;
    270    private static final int POS_2 = 2;
    271    private static final int POS_3 = 3;
    272    private static final byte[] ONE_ZERO_BYTE = new byte[1];
    273
    274    /**
    275     * Length of a "central directory" entry structure without file name, extra fields or comment.
    276     */
    277    private static final int CFH_LEN =
    278    // @formatter:off
    279        /* version made by                 */ ZipConstants.SHORT
    280        /* version needed to extract       */ + ZipConstants.SHORT
    281        /* general purpose bit flag        */ + ZipConstants.SHORT
    282        /* compression method              */ + ZipConstants.SHORT
    283        /* last mod file time              */ + ZipConstants.SHORT
    284        /* last mod file date              */ + ZipConstants.SHORT
    285        /* crc-32                          */ + ZipConstants.WORD
    286        /* compressed size                 */ + ZipConstants.WORD
    287        /* uncompressed size               */ + ZipConstants.WORD
    288        /* file name length                */ + ZipConstants. SHORT
    289        /* extra field length              */ + ZipConstants.SHORT
    290        /* file comment length             */ + ZipConstants.SHORT
    291        /* disk number start               */ + ZipConstants.SHORT
    292        /* internal file attributes        */ + ZipConstants.SHORT
    293        /* external file attributes        */ + ZipConstants.WORD
    294        /* relative offset of local header */ + ZipConstants.WORD;
    295    // @formatter:on
    296
    297    private static final long CFH_SIG = ZipLong.getValue(ZipArchiveOutputStream.CFH_SIG);
    298
    299    /**
    300     * Length of the "End of central directory record" - which is supposed to be the last structure of the archive - without file comment.
    301     */
    302    static final int MIN_EOCD_SIZE =
    303    // @formatter:off
    304        /* end of central dir signature    */ ZipConstants.WORD
    305        /* number of this disk             */ + ZipConstants.SHORT
    306        /* number of the disk with the     */
    307        /* start of the central directory  */ + ZipConstants.SHORT
    308        /* total number of entries in      */
    309        /* the central dir on this disk    */ + ZipConstants.SHORT
    310        /* total number of entries in      */
    311        /* the central dir                 */ + ZipConstants.SHORT
    312        /* size of the central directory   */ + ZipConstants.WORD
    313        /* offset of start of central      */
    314        /* directory with respect to       */
    315        /* the starting disk number        */ + ZipConstants.WORD
    316        /* ZIP file comment length         */ + ZipConstants.SHORT;
    317    // @formatter:on
    318
    319    /**
    320     * Maximum length of the "End of central directory record" with a file comment.
    321     */
    322    private static final int MAX_EOCD_SIZE = MIN_EOCD_SIZE
    323    // @formatter:off
    324        /* maximum length of ZIP file comment */ + ZipConstants.ZIP64_MAGIC_SHORT;
    325    // @formatter:on
    326
    327    /**
    328     * Offset of the field that holds the location of the length of the central directory inside the "End of central directory record" relative to the start of
    329     * the "End of central directory record".
    330     */
    331    private static final int CFD_LENGTH_OFFSET =
    332    // @formatter:off
    333        /* end of central dir signature    */ ZipConstants.WORD
    334        /* number of this disk             */ + ZipConstants.SHORT
    335        /* number of the disk with the     */
    336        /* start of the central directory  */ + ZipConstants.SHORT
    337        /* total number of entries in      */
    338        /* the central dir on this disk    */ + ZipConstants.SHORT
    339        /* total number of entries in      */
    340        /* the central dir                 */ + ZipConstants.SHORT;
    341    // @formatter:on
    342
    343    /**
    344     * Offset of the field that holds the disk number of the first central directory entry inside the "End of central directory record" relative to the start of
    345     * the "End of central directory record".
    346     */
    347    private static final int CFD_DISK_OFFSET =
    348    // @formatter:off
    349            /* end of central dir signature    */ ZipConstants.WORD
    350            /* number of this disk             */ + ZipConstants.SHORT;
    351    // @formatter:on
    352
    353    /**
    354     * Offset of the field that holds the location of the first central directory entry inside the "End of central directory record" relative to the "number of
    355     * the disk with the start of the central directory".
    356     */
    357    private static final int CFD_LOCATOR_RELATIVE_OFFSET =
    358    // @formatter:off
    359            /* total number of entries in      */
    360            /* the central dir on this disk    */ + ZipConstants.SHORT
    361            /* total number of entries in      */
    362            /* the central dir                 */ + ZipConstants.SHORT
    363            /* size of the central directory   */ + ZipConstants.WORD;
    364    // @formatter:on
    365
    366    /**
    367     * Length of the "Zip64 end of central directory locator" - which should be right in front of the "end of central directory record" if one is present at
    368     * all.
    369     */
    370    private static final int ZIP64_EOCDL_LENGTH =
    371    // @formatter:off
    372        /* zip64 end of central dir locator sig */ ZipConstants.WORD
    373        /* number of the disk with the start    */
    374        /* start of the zip64 end of            */
    375        /* central directory                    */ + ZipConstants.WORD
    376        /* relative offset of the zip64         */
    377        /* end of central directory record      */ + ZipConstants.DWORD
    378        /* total number of disks                */ + ZipConstants.WORD;
    379    // @formatter:on
    380
    381    /**
    382     * Offset of the field that holds the location of the "Zip64 end of central directory record" inside the "Zip64 end of central directory locator" relative
    383     * to the start of the "Zip64 end of central directory locator".
    384     */
    385    private static final int ZIP64_EOCDL_LOCATOR_OFFSET =
    386    // @formatter:off
    387        /* zip64 end of central dir locator sig */ ZipConstants.WORD
    388        /* number of the disk with the start    */
    389        /* start of the zip64 end of            */
    390        /* central directory                    */ + ZipConstants.WORD;
    391    // @formatter:on
    392
    393    /**
    394     * Offset of the field that holds the location of the first central directory entry inside the "Zip64 end of central directory record" relative to the start
    395     * of the "Zip64 end of central directory record".
    396     */
    397    private static final int ZIP64_EOCD_CFD_LOCATOR_OFFSET =
    398    // @formatter:off
    399        /* zip64 end of central dir        */
    400        /* signature                       */ ZipConstants.WORD
    401        /* size of zip64 end of central    */
    402        /* directory record                */ + ZipConstants.DWORD
    403        /* version made by                 */ + ZipConstants.SHORT
    404        /* version needed to extract       */ + ZipConstants.SHORT
    405        /* number of this disk             */ + ZipConstants.WORD
    406        /* number of the disk with the     */
    407        /* start of the central directory  */ + ZipConstants.WORD
    408        /* total number of entries in the  */
    409        /* central directory on this disk  */ + ZipConstants.DWORD
    410        /* total number of entries in the  */
    411        /* central directory               */ + ZipConstants.DWORD
    412        /* size of the central directory   */ + ZipConstants.DWORD;
    413    // @formatter:on
    414
    415    /**
    416     * Offset of the field that holds the disk number of the first central directory entry inside the "Zip64 end of central directory record" relative to the
    417     * start of the "Zip64 end of central directory record".
    418     */
    419    private static final int ZIP64_EOCD_CFD_DISK_OFFSET =
    420    // @formatter:off
    421            /* zip64 end of central dir        */
    422            /* signature                       */ ZipConstants.WORD
    423            /* size of zip64 end of central    */
    424            /* directory record                */ + ZipConstants.DWORD
    425            /* version made by                 */ + ZipConstants.SHORT
    426            /* version needed to extract       */ + ZipConstants.SHORT
    427            /* number of this disk             */ + ZipConstants.WORD;
    428    // @formatter:on
    429
    430    /**
    431     * Offset of the field that holds the location of the first central directory entry inside the "Zip64 end of central directory record" relative to the
    432     * "number of the disk with the start of the central directory".
    433     */
    434    private static final int ZIP64_EOCD_CFD_LOCATOR_RELATIVE_OFFSET =
    435    // @formatter:off
    436            /* total number of entries in the  */
    437            /* central directory on this disk  */ ZipConstants.DWORD
    438            /* total number of entries in the  */
    439            /* central directory               */ + ZipConstants.DWORD
    440            /* size of the central directory   */ + ZipConstants.DWORD;
    441    // @formatter:on
    442
    443    /**
    444     * Number of bytes in local file header up to the &quot;length of file name&quot; entry.
    445     */
    446    private static final long LFH_OFFSET_FOR_FILENAME_LENGTH =
    447    // @formatter:off
    448        /* local file header signature     */ ZipConstants.WORD
    449        /* version needed to extract       */ + ZipConstants.SHORT
    450        /* general purpose bit flag        */ + ZipConstants.SHORT
    451        /* compression method              */ + ZipConstants.SHORT
    452        /* last mod file time              */ + ZipConstants.SHORT
    453        /* last mod file date              */ + ZipConstants.SHORT
    454        /* crc-32                          */ + ZipConstants.WORD
    455        /* compressed size                 */ + ZipConstants.WORD
    456        /* uncompressed size               */ + (long) ZipConstants.WORD;
    457    // @formatter:on
    458
    459    /**
    460     * Compares two ZipArchiveEntries based on their offset within the archive.
    461     * <p>
    462     * Won't return any meaningful results if one of the entries isn't part of the archive at all.
    463     * </p>
    464     *
    465     * @since 1.1
    466     */
    467    private static final Comparator<ZipArchiveEntry> offsetComparator = Comparator.comparingLong(ZipArchiveEntry::getDiskNumberStart)
    468            .thenComparingLong(ZipArchiveEntry::getLocalHeaderOffset);
    469
    470    /**
    471     * Creates a new Builder.
    472     *
    473     * @return a new Builder.
    474     * @since 1.26.0
    475     */
    476    public static Builder builder() {
    477        return new Builder();
    478    }
    479
    480    /**
    481     * Closes a ZIP file quietly; throwing no IOException, does nothing on null input.
    482     *
    483     * @param zipFile file to close, can be null
    484     */
    485    public static void closeQuietly(final ZipFile zipFile) {
    486        org.apache.commons.io.IOUtils.closeQuietly(zipFile);
    487    }
    488
    489    /**
    490     * Creates a new SeekableByteChannel for reading.
    491     *
    492     * @param path the path to the file to open or create
    493     * @return a new seekable byte channel
    494     * @throws IOException if an I/O error occurs
    495     */
    496    private static SeekableByteChannel newReadByteChannel(final Path path) throws IOException {
    497        return Files.newByteChannel(path, READ);
    498    }
    499
    500    private static SeekableByteChannel openZipChannel(final Path path, final long maxNumberOfDisks, final OpenOption[] openOptions) throws IOException {
    501        final FileChannel channel = FileChannel.open(path, StandardOpenOption.READ);
    502        final List<FileChannel> channels = new ArrayList<>();
    503        try {
    504            final boolean is64 = positionAtEndOfCentralDirectoryRecord(channel);
    505            long numberOfDisks;
    506            if (is64) {
    507                channel.position(channel.position() + ZipConstants.WORD + ZipConstants.WORD + ZipConstants.DWORD);
    508                final ByteBuffer buf = ByteBuffer.allocate(ZipConstants.WORD);
    509                buf.order(ByteOrder.LITTLE_ENDIAN);
    510                IOUtils.readFully(channel, buf);
    511                buf.flip();
    512                numberOfDisks = buf.getInt() & 0xffffffffL;
    513            } else {
    514                channel.position(channel.position() + ZipConstants.WORD);
    515                final ByteBuffer buf = ByteBuffer.allocate(ZipConstants.SHORT);
    516                buf.order(ByteOrder.LITTLE_ENDIAN);
    517                IOUtils.readFully(channel, buf);
    518                buf.flip();
    519                numberOfDisks = (buf.getShort() & 0xffff) + 1;
    520            }
    521            if (numberOfDisks > Math.min(maxNumberOfDisks, Integer.MAX_VALUE)) {
    522                throw new IOException("Too many disks for zip archive, max=" + Math.min(maxNumberOfDisks, Integer.MAX_VALUE) + " actual=" + numberOfDisks);
    523            }
    524
    525            if (numberOfDisks <= 1) {
    526                return channel;
    527            }
    528            channel.close();
    529
    530            final Path parent = path.getParent();
    531            final String basename = FilenameUtils.removeExtension(Objects.toString(path.getFileName(), null));
    532
    533            return ZipSplitReadOnlySeekableByteChannel.forPaths(IntStream.range(0, (int) numberOfDisks).mapToObj(i -> {
    534                if (i == numberOfDisks - 1) {
    535                    return path;
    536                }
    537                final Path lowercase = parent.resolve(String.format("%s.z%02d", basename, i + 1));
    538                if (Files.exists(lowercase)) {
    539                    return lowercase;
    540                }
    541                final Path uppercase = parent.resolve(String.format("%s.Z%02d", basename, i + 1));
    542                if (Files.exists(uppercase)) {
    543                    return uppercase;
    544                }
    545                return lowercase;
    546            }).collect(Collectors.toList()), openOptions);
    547        } catch (final Throwable ex) {
    548            org.apache.commons.io.IOUtils.closeQuietly(channel);
    549            channels.forEach(org.apache.commons.io.IOUtils::closeQuietly);
    550            throw ex;
    551        }
    552    }
    553
    554    /**
    555     * Searches for the and positions the stream at the start of the &quot;End of central dir record&quot;.
    556     *
    557     * @return true if it's Zip64 end of central directory or false if it's Zip32
    558     */
    559    private static boolean positionAtEndOfCentralDirectoryRecord(final SeekableByteChannel channel) throws IOException {
    560        final boolean found = tryToLocateSignature(channel, MIN_EOCD_SIZE, MAX_EOCD_SIZE, ZipArchiveOutputStream.EOCD_SIG);
    561        if (!found) {
    562            throw new ZipException("Archive is not a ZIP archive");
    563        }
    564        boolean found64 = false;
    565        final long position = channel.position();
    566        if (position > ZIP64_EOCDL_LENGTH) {
    567            final ByteBuffer wordBuf = ByteBuffer.allocate(4);
    568            channel.position(channel.position() - ZIP64_EOCDL_LENGTH);
    569            wordBuf.rewind();
    570            IOUtils.readFully(channel, wordBuf);
    571            wordBuf.flip();
    572            found64 = wordBuf.equals(ByteBuffer.wrap(ZipArchiveOutputStream.ZIP64_EOCD_LOC_SIG));
    573            if (!found64) {
    574                channel.position(position);
    575            } else {
    576                channel.position(channel.position() - ZipConstants.WORD);
    577            }
    578        }
    579
    580        return found64;
    581    }
    582
    583    /**
    584     * Searches the archive backwards from minDistance to maxDistance for the given signature, positions the RandomaccessFile right at the signature if it has
    585     * been found.
    586     */
    587    private static boolean tryToLocateSignature(final SeekableByteChannel channel, final long minDistanceFromEnd, final long maxDistanceFromEnd,
    588            final byte[] sig) throws IOException {
    589        final ByteBuffer wordBuf = ByteBuffer.allocate(ZipConstants.WORD);
    590        boolean found = false;
    591        long off = channel.size() - minDistanceFromEnd;
    592        final long stopSearching = Math.max(0L, channel.size() - maxDistanceFromEnd);
    593        if (off >= 0) {
    594            for (; off >= stopSearching; off--) {
    595                channel.position(off);
    596                try {
    597                    wordBuf.rewind();
    598                    IOUtils.readFully(channel, wordBuf);
    599                    wordBuf.flip();
    600                } catch (final EOFException ex) { // NOSONAR
    601                    break;
    602                }
    603                int curr = wordBuf.get();
    604                if (curr == sig[POS_0]) {
    605                    curr = wordBuf.get();
    606                    if (curr == sig[POS_1]) {
    607                        curr = wordBuf.get();
    608                        if (curr == sig[POS_2]) {
    609                            curr = wordBuf.get();
    610                            if (curr == sig[POS_3]) {
    611                                found = true;
    612                                break;
    613                            }
    614                        }
    615                    }
    616                }
    617            }
    618        }
    619        if (found) {
    620            channel.position(off);
    621        }
    622        return found;
    623    }
    624
    625    /**
    626     * List of entries in the order they appear inside the central directory.
    627     */
    628    private final List<ZipArchiveEntry> entries = new LinkedList<>();
    629
    630    /**
    631     * Maps String to list of ZipArchiveEntrys, name -> actual entries.
    632     */
    633    private final Map<String, LinkedList<ZipArchiveEntry>> nameMap = new HashMap<>(HASH_SIZE);
    634
    635    /**
    636     * The encoding to use for file names and the file comment.
    637     * <p>
    638     * For a list of possible values see <a href="Supported Encodings">https://docs.oracle.com/javase/8/docs/technotes/guides/intl/encoding.doc.html</a>.
    639     * Defaults to UTF-8.
    640     * </p>
    641     */
    642    private final Charset encoding;
    643
    644    /**
    645     * The ZIP encoding to use for file names and the file comment.
    646     */
    647    private final ZipEncoding zipEncoding;
    648
    649    /**
    650     * The actual data source.
    651     */
    652    private final SeekableByteChannel archive;
    653
    654    /**
    655     * Whether to look for and use Unicode extra fields.
    656     */
    657    private final boolean useUnicodeExtraFields;
    658
    659    /**
    660     * Whether the file is closed.
    661     */
    662    private volatile boolean closed = true;
    663
    664    /**
    665     * Whether the ZIP archive is a split ZIP archive
    666     */
    667    private final boolean isSplitZipArchive;
    668
    669    // cached buffers - must only be used locally in the class (COMPRESS-172 - reduce garbage collection)
    670    private final byte[] dwordBuf = new byte[ZipConstants.DWORD];
    671
    672    private final byte[] wordBuf = new byte[ZipConstants.WORD];
    673
    674    private final byte[] cfhBuf = new byte[CFH_LEN];
    675
    676    private final byte[] shortBuf = new byte[ZipConstants.SHORT];
    677
    678    private final ByteBuffer dwordBbuf = ByteBuffer.wrap(dwordBuf);
    679
    680    private final ByteBuffer wordBbuf = ByteBuffer.wrap(wordBuf);
    681
    682    private final ByteBuffer cfhBbuf = ByteBuffer.wrap(cfhBuf);
    683
    684    private final ByteBuffer shortBbuf = ByteBuffer.wrap(shortBuf);
    685
    686    private long centralDirectoryStartDiskNumber, centralDirectoryStartRelativeOffset;
    687
    688    private long centralDirectoryStartOffset;
    689
    690    private long firstLocalFileHeaderOffset;
    691
    692    /**
    693     * Opens the given file for reading, assuming "UTF8" for file names.
    694     *
    695     * @param file the archive.
    696     *
    697     * @throws IOException if an error occurs while reading the file.
    698     * @deprecated Use {@link Builder#get()}.
    699     */
    700    @Deprecated
    701    public ZipFile(final File file) throws IOException {
    702        this(file, DEFAULT_CHARSET_NAME);
    703    }
    704
    705    /**
    706     * Opens the given file for reading, assuming the specified encoding for file names and scanning for Unicode extra fields.
    707     *
    708     * @param file     the archive.
    709     * @param encoding the encoding to use for file names, use null for the platform's default encoding
    710     * @throws IOException if an error occurs while reading the file.
    711     * @deprecated Use {@link Builder#get()}.
    712     */
    713    @Deprecated
    714    public ZipFile(final File file, final String encoding) throws IOException {
    715        this(file.toPath(), encoding, true);
    716    }
    717
    718    /**
    719     * Opens the given file for reading, assuming the specified encoding for file names.
    720     *
    721     * @param file                  the archive.
    722     * @param encoding              the encoding to use for file names, use null for the platform's default encoding
    723     * @param useUnicodeExtraFields whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    724     * @throws IOException if an error occurs while reading the file.
    725     * @deprecated Use {@link Builder#get()}.
    726     */
    727    @Deprecated
    728    public ZipFile(final File file, final String encoding, final boolean useUnicodeExtraFields) throws IOException {
    729        this(file.toPath(), encoding, useUnicodeExtraFields, false);
    730    }
    731
    732    /**
    733     * Opens the given file for reading, assuming the specified encoding for file names.
    734     * <p>
    735     * By default the central directory record and all local file headers of the archive will be read immediately which may take a considerable amount of time
    736     * when the archive is big. The {@code ignoreLocalFileHeader} parameter can be set to {@code true} which restricts parsing to the central directory.
    737     * Unfortunately the local file header may contain information not present inside of the central directory which will not be available when the argument is
    738     * set to {@code true}. This includes the content of the Unicode extra field, so setting {@code
    739     * ignoreLocalFileHeader} to {@code true} means {@code useUnicodeExtraFields} will be ignored effectively.
    740     * </p>
    741     *
    742     * @param file                  the archive.
    743     * @param encoding              the encoding to use for file names, use null for the platform's default encoding
    744     * @param useUnicodeExtraFields whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    745     * @param ignoreLocalFileHeader whether to ignore information stored inside the local file header (see the notes in this method's Javadoc)
    746     * @throws IOException if an error occurs while reading the file.
    747     * @since 1.19
    748     * @deprecated Use {@link Builder#get()}.
    749     */
    750    @Deprecated
    751    @SuppressWarnings("resource") // Caller closes
    752    public ZipFile(final File file, final String encoding, final boolean useUnicodeExtraFields, final boolean ignoreLocalFileHeader) throws IOException {
    753        this(newReadByteChannel(file.toPath()), file.getAbsolutePath(), encoding, useUnicodeExtraFields, true, ignoreLocalFileHeader);
    754    }
    755
    756    /**
    757     * Opens the given path for reading, assuming "UTF-8" for file names.
    758     *
    759     * @param path path to the archive.
    760     * @throws IOException if an error occurs while reading the file.
    761     * @since 1.22
    762     * @deprecated Use {@link Builder#get()}.
    763     */
    764    @Deprecated
    765    public ZipFile(final Path path) throws IOException {
    766        this(path, DEFAULT_CHARSET_NAME);
    767    }
    768
    769    /**
    770     * Opens the given path for reading, assuming the specified encoding for file names and scanning for Unicode extra fields.
    771     *
    772     * @param path     path to the archive.
    773     * @param encoding the encoding to use for file names, use null for the platform's default encoding
    774     * @throws IOException if an error occurs while reading the file.
    775     * @since 1.22
    776     * @deprecated Use {@link Builder#get()}.
    777     */
    778    @Deprecated
    779    public ZipFile(final Path path, final String encoding) throws IOException {
    780        this(path, encoding, true);
    781    }
    782
    783    /**
    784     * Opens the given path for reading, assuming the specified encoding for file names.
    785     *
    786     * @param path                  path to the archive.
    787     * @param encoding              the encoding to use for file names, use null for the platform's default encoding
    788     * @param useUnicodeExtraFields whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    789     * @throws IOException if an error occurs while reading the file.
    790     * @since 1.22
    791     * @deprecated Use {@link Builder#get()}.
    792     */
    793    @Deprecated
    794    public ZipFile(final Path path, final String encoding, final boolean useUnicodeExtraFields) throws IOException {
    795        this(path, encoding, useUnicodeExtraFields, false);
    796    }
    797
    798    /**
    799     * Opens the given path for reading, assuming the specified encoding for file names.
    800     * <p>
    801     * By default the central directory record and all local file headers of the archive will be read immediately which may take a considerable amount of time
    802     * when the archive is big. The {@code ignoreLocalFileHeader} parameter can be set to {@code true} which restricts parsing to the central directory.
    803     * Unfortunately the local file header may contain information not present inside of the central directory which will not be available when the argument is
    804     * set to {@code true}. This includes the content of the Unicode extra field, so setting {@code
    805     * ignoreLocalFileHeader} to {@code true} means {@code useUnicodeExtraFields} will be ignored effectively.
    806     * </p>
    807     *
    808     * @param path                  path to the archive.
    809     * @param encoding              the encoding to use for file names, use null for the platform's default encoding
    810     * @param useUnicodeExtraFields whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    811     * @param ignoreLocalFileHeader whether to ignore information stored inside the local file header (see the notes in this method's Javadoc)
    812     * @throws IOException if an error occurs while reading the file.
    813     * @since 1.22
    814     * @deprecated Use {@link Builder#get()}.
    815     */
    816    @SuppressWarnings("resource") // Caller closes
    817    @Deprecated
    818    public ZipFile(final Path path, final String encoding, final boolean useUnicodeExtraFields, final boolean ignoreLocalFileHeader) throws IOException {
    819        this(newReadByteChannel(path), path.toAbsolutePath().toString(), encoding, useUnicodeExtraFields, true, ignoreLocalFileHeader);
    820    }
    821
    822    /**
    823     * Opens the given channel for reading, assuming "UTF-8" for file names.
    824     * <p>
    825     * {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
    826     * </p>
    827     *
    828     * @param channel the archive.
    829     *
    830     * @throws IOException if an error occurs while reading the file.
    831     * @since 1.13
    832     * @deprecated Use {@link Builder#get()}.
    833     */
    834    @Deprecated
    835    public ZipFile(final SeekableByteChannel channel) throws IOException {
    836        this(channel, "a SeekableByteChannel", DEFAULT_CHARSET_NAME, true);
    837    }
    838
    839    /**
    840     * Opens the given channel for reading, assuming the specified encoding for file names.
    841     * <p>
    842     * {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
    843     * </p>
    844     *
    845     * @param channel  the archive.
    846     * @param encoding the encoding to use for file names, use null for the platform's default encoding
    847     * @throws IOException if an error occurs while reading the file.
    848     * @since 1.13
    849     * @deprecated Use {@link Builder#get()}.
    850     */
    851    @Deprecated
    852    public ZipFile(final SeekableByteChannel channel, final String encoding) throws IOException {
    853        this(channel, "a SeekableByteChannel", encoding, true);
    854    }
    855
    856    private ZipFile(final SeekableByteChannel channel, final String channelDescription, final Charset encoding, final boolean useUnicodeExtraFields,
    857            final boolean closeOnError, final boolean ignoreLocalFileHeader) throws IOException {
    858        this.isSplitZipArchive = channel instanceof ZipSplitReadOnlySeekableByteChannel;
    859        this.encoding = Charsets.toCharset(encoding, Builder.DEFAULT_CHARSET);
    860        this.zipEncoding = ZipEncodingHelper.getZipEncoding(encoding);
    861        this.useUnicodeExtraFields = useUnicodeExtraFields;
    862        this.archive = channel;
    863        boolean success = false;
    864        try {
    865            final Map<ZipArchiveEntry, NameAndComment> entriesWithoutUTF8Flag = populateFromCentralDirectory();
    866            if (!ignoreLocalFileHeader) {
    867                resolveLocalFileHeaderData(entriesWithoutUTF8Flag);
    868            }
    869            fillNameMap();
    870            success = true;
    871        } catch (final IOException e) {
    872            throw new IOException("Error reading Zip content from " + channelDescription, e);
    873        } finally {
    874            this.closed = !success;
    875            if (!success && closeOnError) {
    876                org.apache.commons.io.IOUtils.closeQuietly(archive);
    877            }
    878        }
    879    }
    880
    881    /**
    882     * Opens the given channel for reading, assuming the specified encoding for file names.
    883     * <p>
    884     * {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
    885     * </p>
    886     *
    887     * @param channel               the archive.
    888     * @param channelDescription    description of the archive, used for error messages only.
    889     * @param encoding              the encoding to use for file names, use null for the platform's default encoding
    890     * @param useUnicodeExtraFields whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    891     * @throws IOException if an error occurs while reading the file.
    892     * @since 1.13
    893     * @deprecated Use {@link Builder#get()}.
    894     */
    895    @Deprecated
    896    public ZipFile(final SeekableByteChannel channel, final String channelDescription, final String encoding, final boolean useUnicodeExtraFields)
    897            throws IOException {
    898        this(channel, channelDescription, encoding, useUnicodeExtraFields, false, false);
    899    }
    900
    901    /**
    902     * Opens the given channel for reading, assuming the specified encoding for file names.
    903     * <p>
    904     * {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
    905     * </p>
    906     * <p>
    907     * By default the central directory record and all local file headers of the archive will be read immediately which may take a considerable amount of time
    908     * when the archive is big. The {@code ignoreLocalFileHeader} parameter can be set to {@code true} which restricts parsing to the central directory.
    909     * Unfortunately the local file header may contain information not present inside of the central directory which will not be available when the argument is
    910     * set to {@code true}. This includes the content of the Unicode extra field, so setting {@code
    911     * ignoreLocalFileHeader} to {@code true} means {@code useUnicodeExtraFields} will be ignored effectively.
    912     * </p>
    913     *
    914     * @param channel               the archive.
    915     * @param channelDescription    description of the archive, used for error messages only.
    916     * @param encoding              the encoding to use for file names, use null for the platform's default encoding
    917     * @param useUnicodeExtraFields whether to use InfoZIP Unicode Extra Fields (if present) to set the file names.
    918     * @param ignoreLocalFileHeader whether to ignore information stored inside the local file header (see the notes in this method's Javadoc)
    919     * @throws IOException if an error occurs while reading the file.
    920     * @since 1.19
    921     * @deprecated Use {@link Builder#get()}.
    922     */
    923    @Deprecated
    924    public ZipFile(final SeekableByteChannel channel, final String channelDescription, final String encoding, final boolean useUnicodeExtraFields,
    925            final boolean ignoreLocalFileHeader) throws IOException {
    926        this(channel, channelDescription, encoding, useUnicodeExtraFields, false, ignoreLocalFileHeader);
    927    }
    928
    929    private ZipFile(final SeekableByteChannel channel, final String channelDescription, final String encoding, final boolean useUnicodeExtraFields,
    930            final boolean closeOnError, final boolean ignoreLocalFileHeader) throws IOException {
    931        this(channel, channelDescription, Charsets.toCharset(encoding), useUnicodeExtraFields, closeOnError, ignoreLocalFileHeader);
    932    }
    933
    934    /**
    935     * Opens the given file for reading, assuming "UTF-8".
    936     *
    937     * @param name name of the archive.
    938     * @throws IOException if an error occurs while reading the file.
    939     * @deprecated Use {@link Builder#get()}.
    940     */
    941    @Deprecated
    942    public ZipFile(final String name) throws IOException {
    943        this(new File(name).toPath(), DEFAULT_CHARSET_NAME);
    944    }
    945
    946    /**
    947     * Opens the given file for reading, assuming the specified encoding for file names, scanning unicode extra fields.
    948     *
    949     * @param name     name of the archive.
    950     * @param encoding the encoding to use for file names, use null for the platform's default encoding
    951     * @throws IOException if an error occurs while reading the file.
    952     * @deprecated Use {@link Builder#get()}.
    953     */
    954    @Deprecated
    955    public ZipFile(final String name, final String encoding) throws IOException {
    956        this(new File(name).toPath(), encoding, true);
    957    }
    958
    959    /**
    960     * Whether this class is able to read the given entry.
    961     * <p>
    962     * May return false if it is set up to use encryption or a compression method that hasn't been implemented yet.
    963     * </p>
    964     *
    965     * @since 1.1
    966     * @param entry the entry
    967     * @return whether this class is able to read the given entry.
    968     */
    969    public boolean canReadEntryData(final ZipArchiveEntry entry) {
    970        return ZipUtil.canHandleEntryData(entry);
    971    }
    972
    973    /**
    974     * Closes the archive.
    975     *
    976     * @throws IOException if an error occurs closing the archive.
    977     */
    978    @Override
    979    public void close() throws IOException {
    980        // this flag is only written here and read in finalize() which
    981        // can never be run in parallel.
    982        // no synchronization needed.
    983        closed = true;
    984        archive.close();
    985    }
    986
    987    /**
    988     * Transfer selected entries from this ZIP file to a given #ZipArchiveOutputStream. Compression and all other attributes will be as in this file.
    989     * <p>
    990     * This method transfers entries based on the central directory of the ZIP file.
    991     * </p>
    992     *
    993     * @param target    The zipArchiveOutputStream to write the entries to
    994     * @param predicate A predicate that selects which entries to write
    995     * @throws IOException on error
    996     */
    997    public void copyRawEntries(final ZipArchiveOutputStream target, final ZipArchiveEntryPredicate predicate) throws IOException {
    998        final Enumeration<ZipArchiveEntry> src = getEntriesInPhysicalOrder();
    999        while (src.hasMoreElements()) {
    1000            final ZipArchiveEntry entry = src.nextElement();
    1001            if (predicate.test(entry)) {
    1002                target.addRawArchiveEntry(entry, getRawInputStream(entry));
    1003            }
    1004        }
    1005    }
    1006
    1007    /**
    1008     * Creates new BoundedInputStream, according to implementation of underlying archive channel.
    1009     */
    1010    private BoundedArchiveInputStream createBoundedInputStream(final long start, final long remaining) {
    1011        if (start < 0 || remaining < 0 || start + remaining < start) {
    1012            throw new IllegalArgumentException("Corrupted archive, stream boundaries" + " are out of range");
    1013        }
    1014        return archive instanceof FileChannel ? new BoundedFileChannelInputStream(start, remaining, (FileChannel) archive)
    1015                : new BoundedSeekableByteChannelInputStream(start, remaining, archive);
    1016    }
    1017
    1018    private void fillNameMap() {
    1019        entries.forEach(ze -> {
    1020            // entries are filled in populateFromCentralDirectory and
    1021            // never modified
    1022            final String name = ze.getName();
    1023            final LinkedList<ZipArchiveEntry> entriesOfThatName = nameMap.computeIfAbsent(name, k -> new LinkedList<>());
    1024            entriesOfThatName.addLast(ze);
    1025        });
    1026    }
    1027
    1028    /**
    1029     * Ensures that the close method of this ZIP file is called when there are no more references to it.
    1030     *
    1031     * @see #close()
    1032     */
    1033    @Override
    1034    protected void finalize() throws Throwable {
    1035        try {
    1036            if (!closed) {
    1037                close();
    1038            }
    1039        } finally {
    1040            super.finalize();
    1041        }
    1042    }
    1043
    1044    /**
    1045     * Gets an InputStream for reading the content before the first local file header.
    1046     *
    1047     * @return null if there is no content before the first local file header. Otherwise, returns a stream to read the content before the first local file
    1048     *         header.
    1049     * @since 1.23
    1050     */
    1051    public InputStream getContentBeforeFirstLocalFileHeader() {
    1052        return firstLocalFileHeaderOffset == 0 ? null : createBoundedInputStream(0, firstLocalFileHeaderOffset);
    1053    }
    1054
    1055    private long getDataOffset(final ZipArchiveEntry ze) throws IOException {
    1056        final long s = ze.getDataOffset();
    1057        if (s == EntryStreamOffsets.OFFSET_UNKNOWN) {
    1058            setDataOffset(ze);
    1059            return ze.getDataOffset();
    1060        }
    1061        return s;
    1062    }
    1063
    1064    /**
    1065     * Gets the encoding to use for file names and the file comment.
    1066     *
    1067     * @return null if using the platform's default character encoding.
    1068     */
    1069    public String getEncoding() {
    1070        return encoding.name();
    1071    }
    1072
    1073    /**
    1074     * Gets all entries.
    1075     * <p>
    1076     * Entries will be returned in the same order they appear within the archive's central directory.
    1077     * </p>
    1078     *
    1079     * @return all entries as {@link ZipArchiveEntry} instances
    1080     */
    1081    public Enumeration<ZipArchiveEntry> getEntries() {
    1082        return Collections.enumeration(entries);
    1083    }
    1084
    1085    /**
    1086     * Gets all named entries in the same order they appear within the archive's central directory.
    1087     *
    1088     * @param name name of the entry.
    1089     * @return the Iterable&lt;ZipArchiveEntry&gt; corresponding to the given name
    1090     * @since 1.6
    1091     */
    1092    public Iterable<ZipArchiveEntry> getEntries(final String name) {
    1093        return nameMap.getOrDefault(name, ZipArchiveEntry.EMPTY_LINKED_LIST);
    1094    }
    1095
    1096    /**
    1097     * Gets all entries in physical order.
    1098     * <p>
    1099     * Entries will be returned in the same order their contents appear within the archive.
    1100     * </p>
    1101     *
    1102     * @return all entries as {@link ZipArchiveEntry} instances
    1103     *
    1104     * @since 1.1
    1105     */
    1106    public Enumeration<ZipArchiveEntry> getEntriesInPhysicalOrder() {
    1107        final ZipArchiveEntry[] allEntries = entries.toArray(ZipArchiveEntry.EMPTY_ARRAY);
    1108        return Collections.enumeration(Arrays.asList(sortByOffset(allEntries)));
    1109    }
    1110
    1111    /**
    1112     * Gets all named entries in the same order their contents appear within the archive.
    1113     *
    1114     * @param name name of the entry.
    1115     * @return the Iterable&lt;ZipArchiveEntry&gt; corresponding to the given name
    1116     * @since 1.6
    1117     */
    1118    public Iterable<ZipArchiveEntry> getEntriesInPhysicalOrder(final String name) {
    1119        final LinkedList<ZipArchiveEntry> linkedList = nameMap.getOrDefault(name, ZipArchiveEntry.EMPTY_LINKED_LIST);
    1120        return Arrays.asList(sortByOffset(linkedList.toArray(ZipArchiveEntry.EMPTY_ARRAY)));
    1121    }
    1122
    1123    /**
    1124     * Gets a named entry or {@code null} if no entry by that name exists.
    1125     * <p>
    1126     * If multiple entries with the same name exist the first entry in the archive's central directory by that name is returned.
    1127     * </p>
    1128     *
    1129     * @param name name of the entry.
    1130     * @return the ZipArchiveEntry corresponding to the given name - or {@code null} if not present.
    1131     */
    1132    public ZipArchiveEntry getEntry(final String name) {
    1133        final LinkedList<ZipArchiveEntry> entries = nameMap.get(name);
    1134        return entries != null ? entries.getFirst() : null;
    1135    }
    1136
    1137    /**
    1138     * Gets the offset of the first local file header in the file.
    1139     *
    1140     * @return the length of the content before the first local file header
    1141     * @since 1.23
    1142     */
    1143    public long getFirstLocalFileHeaderOffset() {
    1144        return firstLocalFileHeaderOffset;
    1145    }
    1146
    1147    /**
    1148     * Gets an InputStream for reading the contents of the given entry.
    1149     *
    1150     * @param entry the entry to get the stream for.
    1151     * @return a stream to read the entry from. The returned stream implements {@link InputStreamStatistics}.
    1152     * @throws IOException if unable to create an input stream from the zipEntry.
    1153     */
    1154    public InputStream getInputStream(final ZipArchiveEntry entry) throws IOException {
    1155        if (!(entry instanceof Entry)) {
    1156            return null;
    1157        }
    1158        // cast validity is checked just above
    1159        ZipUtil.checkRequestedFeatures(entry);
    1160
    1161        // doesn't get closed if the method is not supported - which
    1162        // should never happen because of the checkRequestedFeatures
    1163        // call above
    1164        final InputStream is = new BufferedInputStream(getRawInputStream(entry)); // NOSONAR
    1165        switch (ZipMethod.getMethodByCode(entry.getMethod())) {
    1166        case STORED:
    1167            return new StoredStatisticsStream(is);
    1168        case UNSHRINKING:
    1169            return new UnshrinkingInputStream(is);
    1170        case IMPLODING:
    1171            try {
    1172                return new ExplodingInputStream(entry.getGeneralPurposeBit().getSlidingDictionarySize(),
    1173                        entry.getGeneralPurposeBit().getNumberOfShannonFanoTrees(), is);
    1174            } catch (final IllegalArgumentException ex) {
    1175                throw new IOException("bad IMPLODE data", ex);
    1176            }
    1177        case DEFLATED:
    1178            final Inflater inflater = new Inflater(true);
    1179            // Inflater with nowrap=true has this odd contract for a zero padding
    1180            // byte following the data stream; this used to be zlib's requirement
    1181            // and has been fixed a long time ago, but the contract persists so
    1182            // we comply.
    1183            // https://docs.oracle.com/javase/8/docs/api/java/util/zip/Inflater.html#Inflater(boolean)
    1184            return new InflaterInputStreamWithStatistics(new SequenceInputStream(is, new ByteArrayInputStream(ONE_ZERO_BYTE)), inflater) {
    1185                @Override
    1186                public void close() throws IOException {
    1187                    try {
    1188                        super.close();
    1189                    } finally {
    1190                        inflater.end();
    1191                    }
    1192                }
    1193            };
    1194        case BZIP2:
    1195            return new BZip2CompressorInputStream(is);
    1196        case ENHANCED_DEFLATED:
    1197            return new Deflate64CompressorInputStream(is);
    1198        case AES_ENCRYPTED:
    1199        case EXPANDING_LEVEL_1:
    1200        case EXPANDING_LEVEL_2:
    1201        case EXPANDING_LEVEL_3:
    1202        case EXPANDING_LEVEL_4:
    1203        case JPEG:
    1204        case LZMA:
    1205        case PKWARE_IMPLODING:
    1206        case PPMD:
    1207        case TOKENIZATION:
    1208        case UNKNOWN:
    1209        case WAVPACK:
    1210        case XZ:
    1211        default:
    1212            throw new UnsupportedZipFeatureException(ZipMethod.getMethodByCode(entry.getMethod()), entry);
    1213        }
    1214    }
    1215
    1216    /**
    1217     * Gets the raw stream of the archive entry (compressed form).
    1218     * <p>
    1219     * This method does not relate to how/if we understand the payload in the stream, since we really only intend to move it on to somewhere else.
    1220     * </p>
    1221     * <p>
    1222     * Since version 1.22, this method will make an attempt to read the entry's data stream offset, even if the {@code ignoreLocalFileHeader} parameter was
    1223     * {@code true} in the constructor. An IOException can also be thrown from the body of the method if this lookup fails for some reason.
    1224     * </p>
    1225     *
    1226     * @param entry The entry to get the stream for
    1227     * @return The raw input stream containing (possibly) compressed data.
    1228     * @since 1.11
    1229     * @throws IOException if there is a problem reading data offset (added in version 1.22).
    1230     */
    1231    public InputStream getRawInputStream(final ZipArchiveEntry entry) throws IOException {
    1232        if (!(entry instanceof Entry)) {
    1233            return null;
    1234        }
    1235        final long start = getDataOffset(entry);
    1236        if (start == EntryStreamOffsets.OFFSET_UNKNOWN) {
    1237            return null;
    1238        }
    1239        return createBoundedInputStream(start, entry.getCompressedSize());
    1240    }
    1241
    1242    /**
    1243     * Gets the entry's content as a String if isUnixSymlink() returns true for it, otherwise returns null.
    1244     * <p>
    1245     * This method assumes the symbolic link's file name uses the same encoding that as been specified for this ZipFile.
    1246     * </p>
    1247     *
    1248     * @param entry ZipArchiveEntry object that represents the symbolic link
    1249     * @return entry's content as a String
    1250     * @throws IOException problem with content's input stream
    1251     * @since 1.5
    1252     */
    1253    public String getUnixSymlink(final ZipArchiveEntry entry) throws IOException {
    1254        if (entry != null && entry.isUnixSymlink()) {
    1255            try (InputStream in = getInputStream(entry)) {
    1256                return zipEncoding.decode(org.apache.commons.io.IOUtils.toByteArray(in));
    1257            }
    1258        }
    1259        return null;
    1260    }
    1261
    1262    /**
    1263     * Reads the central directory of the given archive and populates the internal tables with ZipArchiveEntry instances.
    1264     * <p>
    1265     * The ZipArchiveEntrys will know all data that can be obtained from the central directory alone, but not the data that requires the local file header or
    1266     * additional data to be read.
    1267     * </p>
    1268     *
    1269     * @return a map of zip entries that didn't have the language encoding flag set when read.
    1270     */
    1271    private Map<ZipArchiveEntry, NameAndComment> populateFromCentralDirectory() throws IOException {
    1272        final HashMap<ZipArchiveEntry, NameAndComment> noUTF8Flag = new HashMap<>();
    1273
    1274        positionAtCentralDirectory();
    1275        centralDirectoryStartOffset = archive.position();
    1276
    1277        wordBbuf.rewind();
    1278        IOUtils.readFully(archive, wordBbuf);
    1279        long sig = ZipLong.getValue(wordBuf);
    1280
    1281        if (sig != CFH_SIG && startsWithLocalFileHeader()) {
    1282            throw new IOException("Central directory is empty, can't expand" + " corrupt archive.");
    1283        }
    1284
    1285        while (sig == CFH_SIG) {
    1286            readCentralDirectoryEntry(noUTF8Flag);
    1287            wordBbuf.rewind();
    1288            IOUtils.readFully(archive, wordBbuf);
    1289            sig = ZipLong.getValue(wordBuf);
    1290        }
    1291        return noUTF8Flag;
    1292    }
    1293
    1294    /**
    1295     * Searches for either the &quot;Zip64 end of central directory locator&quot; or the &quot;End of central dir record&quot;, parses it and positions the
    1296     * stream at the first central directory record.
    1297     */
    1298    private void positionAtCentralDirectory() throws IOException {
    1299        final boolean is64 = positionAtEndOfCentralDirectoryRecord(archive);
    1300        if (!is64) {
    1301            positionAtCentralDirectory32();
    1302        } else {
    1303            positionAtCentralDirectory64();
    1304        }
    1305    }
    1306
    1307    /**
    1308     * Parses the &quot;End of central dir record&quot; and positions the stream at the first central directory record.
    1309     *
    1310     * Expects stream to be positioned at the beginning of the &quot;End of central dir record&quot;.
    1311     */
    1312    private void positionAtCentralDirectory32() throws IOException {
    1313        final long endOfCentralDirectoryRecordOffset = archive.position();
    1314        if (isSplitZipArchive) {
    1315            skipBytes(CFD_DISK_OFFSET);
    1316            shortBbuf.rewind();
    1317            IOUtils.readFully(archive, shortBbuf);
    1318            centralDirectoryStartDiskNumber = ZipShort.getValue(shortBuf);
    1319
    1320            skipBytes(CFD_LOCATOR_RELATIVE_OFFSET);
    1321
    1322            wordBbuf.rewind();
    1323            IOUtils.readFully(archive, wordBbuf);
    1324            centralDirectoryStartRelativeOffset = ZipLong.getValue(wordBuf);
    1325            ((ZipSplitReadOnlySeekableByteChannel) archive).position(centralDirectoryStartDiskNumber, centralDirectoryStartRelativeOffset);
    1326        } else {
    1327            skipBytes(CFD_LENGTH_OFFSET);
    1328            wordBbuf.rewind();
    1329            IOUtils.readFully(archive, wordBbuf);
    1330            final long centralDirectoryLength = ZipLong.getValue(wordBuf);
    1331
    1332            wordBbuf.rewind();
    1333            IOUtils.readFully(archive, wordBbuf);
    1334            centralDirectoryStartDiskNumber = 0;
    1335            centralDirectoryStartRelativeOffset = ZipLong.getValue(wordBuf);
    1336
    1337            firstLocalFileHeaderOffset = Long.max(endOfCentralDirectoryRecordOffset - centralDirectoryLength - centralDirectoryStartRelativeOffset, 0L);
    1338            archive.position(centralDirectoryStartRelativeOffset + firstLocalFileHeaderOffset);
    1339        }
    1340    }
    1341
    1342    /**
    1343     * Parses the &quot;Zip64 end of central directory locator&quot;, finds the &quot;Zip64 end of central directory record&quot; using the parsed information,
    1344     * parses that and positions the stream at the first central directory record.
    1345     *
    1346     * Expects stream to be positioned right behind the &quot;Zip64 end of central directory locator&quot;'s signature.
    1347     */
    1348    private void positionAtCentralDirectory64() throws IOException {
    1349        skipBytes(ZipConstants.WORD);
    1350        if (isSplitZipArchive) {
    1351            wordBbuf.rewind();
    1352            IOUtils.readFully(archive, wordBbuf);
    1353            final long diskNumberOfEOCD = ZipLong.getValue(wordBuf);
    1354
    1355            dwordBbuf.rewind();
    1356            IOUtils.readFully(archive, dwordBbuf);
    1357            final long relativeOffsetOfEOCD = ZipEightByteInteger.getLongValue(dwordBuf);
    1358            ((ZipSplitReadOnlySeekableByteChannel) archive).position(diskNumberOfEOCD, relativeOffsetOfEOCD);
    1359        } else {
    1360            skipBytes(ZIP64_EOCDL_LOCATOR_OFFSET - ZipConstants.WORD /* signature has already been read */);
    1361            dwordBbuf.rewind();
    1362            IOUtils.readFully(archive, dwordBbuf);
    1363            archive.position(ZipEightByteInteger.getLongValue(dwordBuf));
    1364        }
    1365
    1366        wordBbuf.rewind();
    1367        IOUtils.readFully(archive, wordBbuf);
    1368        if (!Arrays.equals(wordBuf, ZipArchiveOutputStream.ZIP64_EOCD_SIG)) {
    1369            throw new ZipException("Archive's ZIP64 end of central directory locator is corrupt.");
    1370        }
    1371
    1372        if (isSplitZipArchive) {
    1373            skipBytes(ZIP64_EOCD_CFD_DISK_OFFSET - ZipConstants.WORD /* signature has already been read */);
    1374            wordBbuf.rewind();
    1375            IOUtils.readFully(archive, wordBbuf);
    1376            centralDirectoryStartDiskNumber = ZipLong.getValue(wordBuf);
    1377
    1378            skipBytes(ZIP64_EOCD_CFD_LOCATOR_RELATIVE_OFFSET);
    1379
    1380            dwordBbuf.rewind();
    1381            IOUtils.readFully(archive, dwordBbuf);
    1382            centralDirectoryStartRelativeOffset = ZipEightByteInteger.getLongValue(dwordBuf);
    1383            ((ZipSplitReadOnlySeekableByteChannel) archive).position(centralDirectoryStartDiskNumber, centralDirectoryStartRelativeOffset);
    1384        } else {
    1385            skipBytes(ZIP64_EOCD_CFD_LOCATOR_OFFSET - ZipConstants.WORD /* signature has already been read */);
    1386            dwordBbuf.rewind();
    1387            IOUtils.readFully(archive, dwordBbuf);
    1388            centralDirectoryStartDiskNumber = 0;
    1389            centralDirectoryStartRelativeOffset = ZipEightByteInteger.getLongValue(dwordBuf);
    1390            archive.position(centralDirectoryStartRelativeOffset);
    1391        }
    1392    }
    1393
    1394    /**
    1395     * Reads an individual entry of the central directory, creates an ZipArchiveEntry from it and adds it to the global maps.
    1396     *
    1397     * @param noUTF8Flag map used to collect entries that don't have their UTF-8 flag set and whose name will be set by data read from the local file header
    1398     *                   later. The current entry may be added to this map.
    1399     */
    1400    private void readCentralDirectoryEntry(final Map<ZipArchiveEntry, NameAndComment> noUTF8Flag) throws IOException {
    1401        cfhBbuf.rewind();
    1402        IOUtils.readFully(archive, cfhBbuf);
    1403        int off = 0;
    1404        final Entry ze = new Entry();
    1405
    1406        final int versionMadeBy = ZipShort.getValue(cfhBuf, off);
    1407        off += ZipConstants.SHORT;
    1408        ze.setVersionMadeBy(versionMadeBy);
    1409        ze.setPlatform(versionMadeBy >> BYTE_SHIFT & NIBLET_MASK);
    1410
    1411        ze.setVersionRequired(ZipShort.getValue(cfhBuf, off));
    1412        off += ZipConstants.SHORT; // version required
    1413
    1414        final GeneralPurposeBit gpFlag = GeneralPurposeBit.parse(cfhBuf, off);
    1415        final boolean hasUTF8Flag = gpFlag.usesUTF8ForNames();
    1416        final ZipEncoding entryEncoding = hasUTF8Flag ? ZipEncodingHelper.ZIP_ENCODING_UTF_8 : zipEncoding;
    1417        if (hasUTF8Flag) {
    1418            ze.setNameSource(ZipArchiveEntry.NameSource.NAME_WITH_EFS_FLAG);
    1419        }
    1420        ze.setGeneralPurposeBit(gpFlag);
    1421        ze.setRawFlag(ZipShort.getValue(cfhBuf, off));
    1422
    1423        off += ZipConstants.SHORT;
    1424
    1425        // noinspection MagicConstant
    1426        ze.setMethod(ZipShort.getValue(cfhBuf, off));
    1427        off += ZipConstants.SHORT;
    1428
    1429        final long time = ZipUtil.dosToJavaTime(ZipLong.getValue(cfhBuf, off));
    1430        ze.setTime(time);
    1431        off += ZipConstants.WORD;
    1432
    1433        ze.setCrc(ZipLong.getValue(cfhBuf, off));
    1434        off += ZipConstants.WORD;
    1435
    1436        long size = ZipLong.getValue(cfhBuf, off);
    1437        if (size < 0) {
    1438            throw new IOException("broken archive, entry with negative compressed size");
    1439        }
    1440        ze.setCompressedSize(size);
    1441        off += ZipConstants.WORD;
    1442
    1443        size = ZipLong.getValue(cfhBuf, off);
    1444        if (size < 0) {
    1445            throw new IOException("broken archive, entry with negative size");
    1446        }
    1447        ze.setSize(size);
    1448        off += ZipConstants.WORD;
    1449
    1450        final int fileNameLen = ZipShort.getValue(cfhBuf, off);
    1451        off += ZipConstants.SHORT;
    1452        if (fileNameLen < 0) {
    1453            throw new IOException("broken archive, entry with negative fileNameLen");
    1454        }
    1455
    1456        final int extraLen = ZipShort.getValue(cfhBuf, off);
    1457        off += ZipConstants.SHORT;
    1458        if (extraLen < 0) {
    1459            throw new IOException("broken archive, entry with negative extraLen");
    1460        }
    1461
    1462        final int commentLen = ZipShort.getValue(cfhBuf, off);
    1463        off += ZipConstants.SHORT;
    1464        if (commentLen < 0) {
    1465            throw new IOException("broken archive, entry with negative commentLen");
    1466        }
    1467
    1468        ze.setDiskNumberStart(ZipShort.getValue(cfhBuf, off));
    1469        off += ZipConstants.SHORT;
    1470
    1471        ze.setInternalAttributes(ZipShort.getValue(cfhBuf, off));
    1472        off += ZipConstants.SHORT;
    1473
    1474        ze.setExternalAttributes(ZipLong.getValue(cfhBuf, off));
    1475        off += ZipConstants.WORD;
    1476
    1477        final byte[] fileName = IOUtils.readRange(archive, fileNameLen);
    1478        if (fileName.length < fileNameLen) {
    1479            throw new EOFException();
    1480        }
    1481        ze.setName(entryEncoding.decode(fileName), fileName);
    1482
    1483        // LFH offset,
    1484        ze.setLocalHeaderOffset(ZipLong.getValue(cfhBuf, off) + firstLocalFileHeaderOffset);
    1485        // data offset will be filled later
    1486        entries.add(ze);
    1487
    1488        final byte[] cdExtraData = IOUtils.readRange(archive, extraLen);
    1489        if (cdExtraData.length < extraLen) {
    1490            throw new EOFException();
    1491        }
    1492        try {
    1493            ze.setCentralDirectoryExtra(cdExtraData);
    1494        } catch (final RuntimeException e) {
    1495            final ZipException z = new ZipException("Invalid extra data in entry " + ze.getName());
    1496            z.initCause(e);
    1497            throw z;
    1498        }
    1499
    1500        setSizesAndOffsetFromZip64Extra(ze);
    1501        sanityCheckLFHOffset(ze);
    1502
    1503        final byte[] comment = IOUtils.readRange(archive, commentLen);
    1504        if (comment.length < commentLen) {
    1505            throw new EOFException();
    1506        }
    1507        ze.setComment(entryEncoding.decode(comment));
    1508
    1509        if (!hasUTF8Flag && useUnicodeExtraFields) {
    1510            noUTF8Flag.put(ze, new NameAndComment(fileName, comment));
    1511        }
    1512
    1513        ze.setStreamContiguous(true);
    1514    }
    1515
    1516    /**
    1517     * Walks through all recorded entries and adds the data available from the local file header.
    1518     * <p>
    1519     * Also records the offsets for the data to read from the entries.
    1520     * </p>
    1521     */
    1522    private void resolveLocalFileHeaderData(final Map<ZipArchiveEntry, NameAndComment> entriesWithoutUTF8Flag) throws IOException {
    1523        for (final ZipArchiveEntry zipArchiveEntry : entries) {
    1524            // entries are filled in populateFromCentralDirectory and never modified
    1525            final Entry ze = (Entry) zipArchiveEntry;
    1526            final int[] lens = setDataOffset(ze);
    1527            final int fileNameLen = lens[0];
    1528            final int extraFieldLen = lens[1];
    1529            skipBytes(fileNameLen);
    1530            final byte[] localExtraData = IOUtils.readRange(archive, extraFieldLen);
    1531            if (localExtraData.length < extraFieldLen) {
    1532                throw new EOFException();
    1533            }
    1534            try {
    1535                ze.setExtra(localExtraData);
    1536            } catch (final RuntimeException e) {
    1537                final ZipException z = new ZipException("Invalid extra data in entry " + ze.getName());
    1538                z.initCause(e);
    1539                throw z;
    1540            }
    1541
    1542            if (entriesWithoutUTF8Flag.containsKey(ze)) {
    1543                final NameAndComment nc = entriesWithoutUTF8Flag.get(ze);
    1544                ZipUtil.setNameAndCommentFromExtraFields(ze, nc.name, nc.comment);
    1545            }
    1546        }
    1547    }
    1548
    1549    private void sanityCheckLFHOffset(final ZipArchiveEntry entry) throws IOException {
    1550        if (entry.getDiskNumberStart() < 0) {
    1551            throw new IOException("broken archive, entry with negative disk number");
    1552        }
    1553        if (entry.getLocalHeaderOffset() < 0) {
    1554            throw new IOException("broken archive, entry with negative local file header offset");
    1555        }
    1556        if (isSplitZipArchive) {
    1557            if (entry.getDiskNumberStart() > centralDirectoryStartDiskNumber) {
    1558                throw new IOException("local file header for " + entry.getName() + " starts on a later disk than central directory");
    1559            }
    1560            if (entry.getDiskNumberStart() == centralDirectoryStartDiskNumber && entry.getLocalHeaderOffset() > centralDirectoryStartRelativeOffset) {
    1561                throw new IOException("local file header for " + entry.getName() + " starts after central directory");
    1562            }
    1563        } else if (entry.getLocalHeaderOffset() > centralDirectoryStartOffset) {
    1564            throw new IOException("local file header for " + entry.getName() + " starts after central directory");
    1565        }
    1566    }
    1567
    1568    private int[] setDataOffset(final ZipArchiveEntry entry) throws IOException {
    1569        long offset = entry.getLocalHeaderOffset();
    1570        if (isSplitZipArchive) {
    1571            ((ZipSplitReadOnlySeekableByteChannel) archive).position(entry.getDiskNumberStart(), offset + LFH_OFFSET_FOR_FILENAME_LENGTH);
    1572            // the offset should be updated to the global offset
    1573            offset = archive.position() - LFH_OFFSET_FOR_FILENAME_LENGTH;
    1574        } else {
    1575            archive.position(offset + LFH_OFFSET_FOR_FILENAME_LENGTH);
    1576        }
    1577        wordBbuf.rewind();
    1578        IOUtils.readFully(archive, wordBbuf);
    1579        wordBbuf.flip();
    1580        wordBbuf.get(shortBuf);
    1581        final int fileNameLen = ZipShort.getValue(shortBuf);
    1582        wordBbuf.get(shortBuf);
    1583        final int extraFieldLen = ZipShort.getValue(shortBuf);
    1584        entry.setDataOffset(offset + LFH_OFFSET_FOR_FILENAME_LENGTH + ZipConstants.SHORT + ZipConstants.SHORT + fileNameLen + extraFieldLen);
    1585        if (entry.getDataOffset() + entry.getCompressedSize() > centralDirectoryStartOffset) {
    1586            throw new IOException("data for " + entry.getName() + " overlaps with central directory.");
    1587        }
    1588        return new int[] { fileNameLen, extraFieldLen };
    1589    }
    1590
    1591    /**
    1592     * If the entry holds a Zip64 extended information extra field, read sizes from there if the entry's sizes are set to 0xFFFFFFFFF, do the same for the
    1593     * offset of the local file header.
    1594     * <p>
    1595     * Ensures the Zip64 extra either knows both compressed and uncompressed size or neither of both as the internal logic in ExtraFieldUtils forces the field
    1596     * to create local header data even if they are never used - and here a field with only one size would be invalid.
    1597     * </p>
    1598     */
    1599    private void setSizesAndOffsetFromZip64Extra(final ZipArchiveEntry entry) throws IOException {
    1600        final ZipExtraField extra = entry.getExtraField(Zip64ExtendedInformationExtraField.HEADER_ID);
    1601        if (extra != null && !(extra instanceof Zip64ExtendedInformationExtraField)) {
    1602            throw new ZipException("archive contains unparseable zip64 extra field");
    1603        }
    1604        final Zip64ExtendedInformationExtraField z64 = (Zip64ExtendedInformationExtraField) extra;
    1605        if (z64 != null) {
    1606            final boolean hasUncompressedSize = entry.getSize() == ZipConstants.ZIP64_MAGIC;
    1607            final boolean hasCompressedSize = entry.getCompressedSize() == ZipConstants.ZIP64_MAGIC;
    1608            final boolean hasRelativeHeaderOffset = entry.getLocalHeaderOffset() == ZipConstants.ZIP64_MAGIC;
    1609            final boolean hasDiskStart = entry.getDiskNumberStart() == ZipConstants.ZIP64_MAGIC_SHORT;
    1610            z64.reparseCentralDirectoryData(hasUncompressedSize, hasCompressedSize, hasRelativeHeaderOffset, hasDiskStart);
    1611
    1612            if (hasUncompressedSize) {
    1613                final long size = z64.getSize().getLongValue();
    1614                if (size < 0) {
    1615                    throw new IOException("broken archive, entry with negative size");
    1616                }
    1617                entry.setSize(size);
    1618            } else if (hasCompressedSize) {
    1619                z64.setSize(new ZipEightByteInteger(entry.getSize()));
    1620            }
    1621
    1622            if (hasCompressedSize) {
    1623                final long size = z64.getCompressedSize().getLongValue();
    1624                if (size < 0) {
    1625                    throw new IOException("broken archive, entry with negative compressed size");
    1626                }
    1627                entry.setCompressedSize(size);
    1628            } else if (hasUncompressedSize) {
    1629                z64.setCompressedSize(new ZipEightByteInteger(entry.getCompressedSize()));
    1630            }
    1631
    1632            if (hasRelativeHeaderOffset) {
    1633                entry.setLocalHeaderOffset(z64.getRelativeHeaderOffset().getLongValue());
    1634            }
    1635
    1636            if (hasDiskStart) {
    1637                entry.setDiskNumberStart(z64.getDiskStartNumber().getValue());
    1638            }
    1639        }
    1640    }
    1641
    1642    /**
    1643     * Skips the given number of bytes or throws an EOFException if skipping failed.
    1644     */
    1645    private void skipBytes(final int count) throws IOException {
    1646        final long currentPosition = archive.position();
    1647        final long newPosition = currentPosition + count;
    1648        if (newPosition > archive.size()) {
    1649            throw new EOFException();
    1650        }
    1651        archive.position(newPosition);
    1652    }
    1653
    1654    /**
    1655     * Sorts entries in place by offset.
    1656     *
    1657     * @param allEntries entries to sort
    1658     * @return the given entries, sorted.
    1659     */
    1660    private ZipArchiveEntry[] sortByOffset(final ZipArchiveEntry[] allEntries) {
    1661        Arrays.sort(allEntries, offsetComparator);
    1662        return allEntries;
    1663    }
    1664
    1665    /**
    1666     * Checks whether the archive starts with an LFH. If it doesn't, it may be an empty archive.
    1667     */
    1668    private boolean startsWithLocalFileHeader() throws IOException {
    1669        archive.position(firstLocalFileHeaderOffset);
    1670        wordBbuf.rewind();
    1671        IOUtils.readFully(archive, wordBbuf);
    1672        return Arrays.equals(wordBuf, ZipArchiveOutputStream.LFH_SIG);
    1673    }
    1674}