/*

 * Copyright (c) 1995, 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package java.util.zip;

import java.io.Closeable;

import java.io.InputStream;

import java.io.IOException;

import java.io.EOFException;

import java.io.File;

import java.io.RandomAccessFile;

import java.nio.charset.Charset;

import java.nio.charset.StandardCharsets;

import java.nio.file.attribute.BasicFileAttributes;

import java.nio.file.Path;

import java.nio.file.Files;

import java.util.ArrayDeque;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Deque;

import java.util.Enumeration;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import java.util.Objects;

import java.util.NoSuchElementException;

import java.util.Spliterator;

import java.util.Spliterators;

import java.util.WeakHashMap;

import java.util.stream.Stream;

import java.util.stream.StreamSupport;

import jdk.internal.misc.JavaUtilZipFileAccess;

import jdk.internal.misc.SharedSecrets;

import jdk.internal.misc.JavaIORandomAccessFileAccess;

import jdk.internal.misc.VM;

import jdk.internal.perf.PerfCounter;

import static java.util.zip.ZipConstants.*;

import static java.util.zip.ZipConstants64.*;

import static java.util.zip.ZipUtils.*;

/**

 * This class is used to read entries from a zip file.

 *

 * <p> Unless otherwise noted, passing a {@code null} argument to a constructor

 * or method in this class will cause a {@link NullPointerException} to be

 * thrown.

 *

 * @author      David Connelly

 */

public

class ZipFile implements ZipConstants, Closeable {

    private final String name;     // zip file name

    private volatile boolean closeRequested;

    private Source zsrc;

    private ZipCoder zc;

    private static final int STORED = ZipEntry.STORED;

    private static final int DEFLATED = ZipEntry.DEFLATED;

    /**

     * Mode flag to open a zip file for reading.

     */

    public static final int OPEN_READ = 0x1;

    /**

     * Mode flag to open a zip file and mark it for deletion.  The file will be

     * deleted some time between the moment that it is opened and the moment

     * that it is closed, but its contents will remain accessible via the

     * {@code ZipFile} object until either the close method is invoked or the

     * virtual machine exits.

     */

    public static final int OPEN_DELETE = 0x4;

    /**

     * Opens a zip file for reading.

     *

     * <p>First, if there is a security manager, its {@code checkRead}

     * method is called with the {@code name} argument as its argument

     * to ensure the read is allowed.

     *

     * <p>The UTF-8 {@link java.nio.charset.Charset charset} is used to

     * decode the entry names and comments.

     *

     * @param name the name of the zip file

     * @throws ZipException if a ZIP format error has occurred

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException if a security manager exists and its

     *         {@code checkRead} method doesn't allow read access to the file.

     *

     * @see SecurityManager#checkRead(java.lang.String)

     */

    public ZipFile(String name) throws IOException {

        this(new File(name), OPEN_READ);

    }

    /**

     * Opens a new {@code ZipFile} to read from the specified

     * {@code File} object in the specified mode.  The mode argument

     * must be either {@code OPEN_READ} or {@code OPEN_READ | OPEN_DELETE}.

     *

     * <p>First, if there is a security manager, its {@code checkRead}

     * method is called with the {@code name} argument as its argument to

     * ensure the read is allowed.

     *

     * <p>The UTF-8 {@link java.nio.charset.Charset charset} is used to

     * decode the entry names and comments

     *

     * @param file the ZIP file to be opened for reading

     * @param mode the mode in which the file is to be opened

     * @throws ZipException if a ZIP format error has occurred

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException if a security manager exists and

     *         its {@code checkRead} method

     *         doesn't allow read access to the file,

     *         or its {@code checkDelete} method doesn't allow deleting

     *         the file when the {@code OPEN_DELETE} flag is set.

     * @throws IllegalArgumentException if the {@code mode} argument is invalid

     * @see SecurityManager#checkRead(java.lang.String)

     * @since 1.3

     */

    public ZipFile(File file, int mode) throws IOException {

        this(file, mode, StandardCharsets.UTF_8);

    }

    /**

     * Opens a ZIP file for reading given the specified File object.

     *

     * <p>The UTF-8 {@link java.nio.charset.Charset charset} is used to

     * decode the entry names and comments.

     *

     * @param file the ZIP file to be opened for reading

     * @throws ZipException if a ZIP format error has occurred

     * @throws IOException if an I/O error has occurred

     */

    public ZipFile(File file) throws ZipException, IOException {

        this(file, OPEN_READ);

    }

    /**

     * Opens a new {@code ZipFile} to read from the specified

     * {@code File} object in the specified mode.  The mode argument

     * must be either {@code OPEN_READ} or {@code OPEN_READ | OPEN_DELETE}.

     *

     * <p>First, if there is a security manager, its {@code checkRead}

     * method is called with the {@code name} argument as its argument to

     * ensure the read is allowed.

     *

     * @param file the ZIP file to be opened for reading

     * @param mode the mode in which the file is to be opened

     * @param charset

     *        the {@linkplain java.nio.charset.Charset charset} to

     *        be used to decode the ZIP entry name and comment that are not

     *        encoded by using UTF-8 encoding (indicated by entry's general

     *        purpose flag).

     *

     * @throws ZipException if a ZIP format error has occurred

     * @throws IOException if an I/O error has occurred

     *

     * @throws SecurityException

     *         if a security manager exists and its {@code checkRead}

     *         method doesn't allow read access to the file,or its

     *         {@code checkDelete} method doesn't allow deleting the

     *         file when the {@code OPEN_DELETE} flag is set

     *

     * @throws IllegalArgumentException if the {@code mode} argument is invalid

     *

     * @see SecurityManager#checkRead(java.lang.String)

     *

     * @since 1.7

     */

    public ZipFile(File file, int mode, Charset charset) throws IOException

    {

        if (((mode & OPEN_READ) == 0) ||

            ((mode & ~(OPEN_READ | OPEN_DELETE)) != 0)) {

            throw new IllegalArgumentException("Illegal mode: 0x"+

                                               Integer.toHexString(mode));

        }

        String name = file.getPath();

        SecurityManager sm = System.getSecurityManager();

        if (sm != null) {

            sm.checkRead(name);

            if ((mode & OPEN_DELETE) != 0) {

                sm.checkDelete(name);

            }

        }

        Objects.requireNonNull(charset, "charset");

        this.zc = ZipCoder.get(charset);

        this.name = name;

        long t0 = System.nanoTime();

        this.zsrc = Source.get(file, (mode & OPEN_DELETE) != 0);

        PerfCounter.getZipFileOpenTime().addElapsedTimeFrom(t0);

        PerfCounter.getZipFileCount().increment();

    }

    /**

     * Opens a zip file for reading.

     *

     * <p>First, if there is a security manager, its {@code checkRead}

     * method is called with the {@code name} argument as its argument

     * to ensure the read is allowed.

     *

     * @param name the name of the zip file

     * @param charset

     *        the {@linkplain java.nio.charset.Charset charset} to

     *        be used to decode the ZIP entry name and comment that are not

     *        encoded by using UTF-8 encoding (indicated by entry's general

     *        purpose flag).

     *

     * @throws ZipException if a ZIP format error has occurred

     * @throws IOException if an I/O error has occurred

     * @throws SecurityException

     *         if a security manager exists and its {@code checkRead}

     *         method doesn't allow read access to the file

     *

     * @see SecurityManager#checkRead(java.lang.String)

     *

     * @since 1.7

     */

    public ZipFile(String name, Charset charset) throws IOException

    {

        this(new File(name), OPEN_READ, charset);

    }

    /**

     * Opens a ZIP file for reading given the specified File object.

     *

     * @param file the ZIP file to be opened for reading

     * @param charset

     *        The {@linkplain java.nio.charset.Charset charset} to be

     *        used to decode the ZIP entry name and comment (ignored if

     *        the <a href="package-summary.html#lang_encoding"> language

     *        encoding bit</a> of the ZIP entry's general purpose bit

     *        flag is set).

     *

     * @throws ZipException if a ZIP format error has occurred

     * @throws IOException if an I/O error has occurred

     *

     * @since 1.7

     */

    public ZipFile(File file, Charset charset) throws IOException

    {

        this(file, OPEN_READ, charset);

    }

    /**

     * Returns the zip file comment, or null if none.

     *

     * @return the comment string for the zip file, or null if none

     *

     * @throws IllegalStateException if the zip file has been closed

     *

     * Since 1.7

     */

    public String getComment() {

        synchronized (this) {

            ensureOpen();

            if (zsrc.comment == null) {

                return null;

            }

            return zc.toString(zsrc.comment);

        }

    }

    /**

     * Returns the zip file entry for the specified name, or null

     * if not found.

     *

     * @param name the name of the entry

     * @return the zip file entry, or null if not found

     * @throws IllegalStateException if the zip file has been closed

     */

    public ZipEntry getEntry(String name) {

        Objects.requireNonNull(name, "name");

        synchronized (this) {

            ensureOpen();

            int pos = zsrc.getEntryPos(zc.getBytes(name), true);

            if (pos != -1) {

                return getZipEntry(name, pos);

            }

        }

        return null;

    }

    // The outstanding inputstreams that need to be closed,

    // mapped to the inflater objects they use.

    private final Map<InputStream, Inflater> streams = new WeakHashMap<>();

    /**

     * Returns an input stream for reading the contents of the specified

     * zip file entry.

     * <p>

     * Closing this ZIP file will, in turn, close all input streams that

     * have been returned by invocations of this method.

     *

     * @param entry the zip file entry

     * @return the input stream for reading the contents of the specified

     * zip file entry.

     * @throws ZipException if a ZIP format error has occurred

     * @throws IOException if an I/O error has occurred

     * @throws IllegalStateException if the zip file has been closed

     */

    public InputStream getInputStream(ZipEntry entry) throws IOException {

        Objects.requireNonNull(entry, "entry");

        int pos = -1;

        ZipFileInputStream in = null;

        synchronized (this) {

            ensureOpen();

            if (!zc.isUTF8() && (entry.flag & EFS) != 0) {

                pos = zsrc.getEntryPos(zc.getBytesUTF8(entry.name), false);

            } else {

                pos = zsrc.getEntryPos(zc.getBytes(entry.name), false);

            }

            if (pos == -1) {

                return null;

            }

            in = new ZipFileInputStream(zsrc.cen, pos);

            switch (CENHOW(zsrc.cen, pos)) {

            case STORED:

                synchronized (streams) {

                    streams.put(in, null);

                }

                return in;

            case DEFLATED:

                // Inflater likes a bit of slack

                // MORE: Compute good size for inflater stream:

                long size = CENLEN(zsrc.cen, pos) + 2;

                if (size > 65536) {

                    size = 8192;

                }

                if (size <= 0) {

                    size = 4096;

                }

                Inflater inf = getInflater();

                InputStream is = new ZipFileInflaterInputStream(in, inf, (int)size);

                synchronized (streams) {

                    streams.put(is, inf);

                }

                return is;

            default:

                throw new ZipException("invalid compression method");

            }

        }

    }

    private class ZipFileInflaterInputStream extends InflaterInputStream {

        private volatile boolean closeRequested;

        private boolean eof = false;

        private final ZipFileInputStream zfin;

        ZipFileInflaterInputStream(ZipFileInputStream zfin, Inflater inf,

                int size) {

            super(zfin, inf, size);

            this.zfin = zfin;

        }

        public void close() throws IOException {

            if (closeRequested)

                return;

            closeRequested = true;

            super.close();

            Inflater inf;

            synchronized (streams) {

                inf = streams.remove(this);

            }

            if (inf != null) {

                releaseInflater(inf);

            }

        }

        // Override fill() method to provide an extra "dummy" byte

        // at the end of the input stream. This is required when

        // using the "nowrap" Inflater option.

        protected void fill() throws IOException {

            if (eof) {

                throw new EOFException("Unexpected end of ZLIB input stream");

            }

            len = in.read(buf, 0, buf.length);

            if (len == -1) {

                buf[0] = 0;

                len = 1;

                eof = true;

            }

            inf.setInput(buf, 0, len);

        }

        public int available() throws IOException {

            if (closeRequested)

                return 0;

            long avail = zfin.size() - inf.getBytesWritten();

            return (avail > (long) Integer.MAX_VALUE ?

                    Integer.MAX_VALUE : (int) avail);

        }

        protected void finalize() throws Throwable {

            close();

        }

    }

    /*

     * Gets an inflater from the list of available inflaters or allocates

     * a new one.

     */

    private Inflater getInflater() {

        Inflater inf;

        synchronized (inflaterCache) {

            while ((inf = inflaterCache.poll()) != null) {

                if (!inf.ended()) {

                    return inf;

                }

            }

        }

        return new Inflater(true);

    }

    /*

     * Releases the specified inflater to the list of available inflaters.

     */

    private void releaseInflater(Inflater inf) {

        if (!inf.ended()) {

            inf.reset();

            synchronized (inflaterCache) {

                inflaterCache.add(inf);

            }

        }

    }

    // List of available Inflater objects for decompression

    private final Deque<Inflater> inflaterCache = new ArrayDeque<>();

    /**

     * Returns the path name of the ZIP file.

     * @return the path name of the ZIP file

     */

    public String getName() {

        return name;

    }

    private class ZipEntryIterator implements Enumeration<ZipEntry>, Iterator<ZipEntry> {

        private int i = 0;

        private final int entryCount;

        public ZipEntryIterator() {

            synchronized (ZipFile.this) {

                ensureOpen();

                this.entryCount = zsrc.total;

            }

        }

        public boolean hasMoreElements() {

            return hasNext();

        }

        public boolean hasNext() {

            return i < entryCount;

        }

        public ZipEntry nextElement() {

            return next();

        }

        public ZipEntry next() {

            synchronized (ZipFile.this) {

                ensureOpen();

                if (!hasNext()) {

                    throw new NoSuchElementException();

                }

                // each "entry" has 3 ints in table entries

                return getZipEntry(null, zsrc.getEntryPos(i++ * 3));

            }