/*

 * Copyright 2005 Sun Microsystems, Inc.  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.

 *

 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

/* @test

 * @bug 6334171

 * @summary Test that zip file's data descriptor is written correctly.

 */

import java.io.*;

import java.util.*;

import java.util.zip.*;

/**

 * Bug 6252735 ZipEntry contains wasteful "temporary storage" fields introduced

 * a regression.  The value of the general purpose flag bit in a LOC header is

 * written incorrectly, because it is computed on stale data.

 * <p>

 * With the bug present, zipbytes2 is written incorrectly: when the LOC

 * header is written, (flag(e) & 8) == 8.  This is correct: the data will be

 * compressed, so we don't have data length, etc. yet; that should be written

 * in the DataDescriptor after the data itself is written.  However, when the

 * ZipOutputStream that wraps zipbytes2 is closed, the data length _is_

 * available, therefore (flag(e) & 8) = 0), therefore the DataDescriptor is

 * not written.  This is why, with the bug, zipbytes1.length == sizeof(ext

 * header) + zipbytes2.length.

 * <p>

 * The result is an invalid LOC header in zipbytes2.  So when we again use

 * copyZip, we attempt to read a data length not from the LOC header but from

 * the non-existent EXT header, and at that position in the file is some

 * arbitrary and incorrect value.

 */

public class DataDescriptor {

    static void copyZip(ZipInputStream in, ZipOutputStream out) throws IOException {

        byte[] buffer = new byte[1 << 14];

        for (ZipEntry ze; (ze = in.getNextEntry()) != null; ) {

            out.putNextEntry(ze);

            // When the bug is present, it shows up here.  The second call to

            // copyZip will throw an exception while reading data.

            for (int nr; 0 < (nr = in.read(buffer)); ) {

                out.write(buffer, 0, nr);

            }

        }

        in.close();

    }

    private static void realMain(String[] args) throws Throwable {

        // Create zip output in byte array zipbytes

        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        ZipOutputStream zos = new ZipOutputStream(baos);

        ZipEntry e = new ZipEntry("testdir/foo");

        byte[] data = "entry data".getBytes("ASCII");

        zos.putNextEntry(e);

        zos.write(data);

        zos.close();

        byte[] zipbytes1 = baos.toByteArray();

        int length1 = zipbytes1.length;

        System.out.println("zip bytes pre-copy length=" + length1);

        // Make a ZipInputStream around zipbytes, and use

        // copyZip to get a new byte array.

        ZipInputStream zis =

            new ZipInputStream(

                new ByteArrayInputStream(zipbytes1));

        baos.reset();

        zos = new ZipOutputStream(baos);

        copyZip(zis, zos);

        zos.close();

        byte[] zipbytes2 = baos.toByteArray();

        int length2 = zipbytes2.length;

        // When the bug is present, pre- and post-copy lengths are different!

        System.out.println("zip bytes post-copy length=" + length2);

        equal(length1, length2);

        check(Arrays.equals(zipbytes1, zipbytes2));

        // Now use copyZip again on the bytes resulting from the previous

        // copy.  When the bug is present, copyZip will get an exception this

        // time.

        baos.reset();

        zos = new ZipOutputStream(baos);

        copyZip(new ZipInputStream(new ByteArrayInputStream(zipbytes2)), zos);

        zos.close();

        byte[] zipbytes3 = baos.toByteArray();

        int length3 = zipbytes3.length;

        System.out.println("zip bytes post-copy length=" + length3);

        equal(length1, length3);

        check(Arrays.equals(zipbytes1, zipbytes3));

    }

    //--------------------- Infrastructure ---------------------------

    static volatile int passed = 0, failed = 0;

    static void pass() {passed++;}

    static void fail() {failed++; Thread.dumpStack();}

    static void fail(String msg) {System.out.println(msg); fail();}

    static void unexpected(Throwable t) {failed++; t.printStackTrace();}

    static void check(boolean cond) {if (cond) pass(); else fail();}

    static void equal(Object x, Object y) {

        if (x == null ? y == null : x.equals(y)) pass();

        else fail(x + " not equal to " + y);}

    public static void main(String[] args) throws Throwable {

        try {realMain(args);} catch (Throwable t) {unexpected(t);}

        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);

        if (failed > 0) throw new AssertionError("Some tests failed");}

}