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diff --git a/libjava/classpath/java/util/zip/GZIPInputStream.java b/libjava/classpath/java/util/zip/GZIPInputStream.java
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+/* GZIPInputStream.java - Input filter for reading gzip file
+   Copyright (C) 1999, 2000, 2001, 2002, 2004 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+ 
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package java.util.zip;
+
+import java.io.EOFException;
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * This filter stream is used to decompress a "GZIP" format stream. 
+ * The "GZIP" format is described in RFC 1952.
+ *
+ * @author John Leuner
+ * @author Tom Tromey
+ * @since JDK 1.1
+ */
+public class GZIPInputStream
+  extends InflaterInputStream
+{
+  /**
+   * The magic number found at the start of a GZIP stream.
+   */
+  public static final int GZIP_MAGIC = 0x8b1f;
+
+  /**
+   * The mask for bit 0 of the flag byte.
+   */
+  static final int FTEXT = 0x1;
+
+  /**
+   * The mask for bit 1 of the flag byte.
+   */
+  static final int FHCRC = 0x2;
+
+  /**
+   * The mask for bit 2 of the flag byte.
+   */
+  static final int FEXTRA = 0x4;
+
+  /**
+   * The mask for bit 3 of the flag byte.
+   */
+  static final int FNAME = 0x8;
+
+  /**
+   * The mask for bit 4 of the flag byte.
+   */
+  static final int FCOMMENT = 0x10;
+
+  /**
+   * The CRC-32 checksum value for uncompressed data.
+   */
+  protected CRC32 crc; 
+
+  /**
+   * Indicates whether or not the end of the stream has been reached.
+   */  
+  protected boolean eos;
+
+  /**
+   * Indicates whether or not the GZIP header has been read in.
+   */
+  private boolean readGZIPHeader;
+
+  /**
+   * Creates a GZIPInputStream with the default buffer size.
+   *
+   * @param in The stream to read compressed data from 
+   *           (in GZIP format).
+   *
+   * @throws IOException if an error occurs during an I/O operation.
+   */
+  public GZIPInputStream(InputStream in)
+    throws IOException
+  {
+    this(in, 4096);
+  }
+
+  /**
+   * Creates a GZIPInputStream with the specified buffer size.
+   *
+   * @param in The stream to read compressed data from 
+   *           (in GZIP format).
+   * @param size The size of the buffer to use.
+   *
+   * @throws IOException if an error occurs during an I/O operation.
+   * @throws IllegalArgumentException if <code>size</code>
+   * is less than or equal to 0.
+   */
+  public GZIPInputStream(InputStream in, int size)
+    throws IOException
+  {
+    super(in, new Inflater(true), size);
+    crc = new CRC32();
+    readHeader();
+  }
+
+  /**
+   * Closes the input stream.
+   *
+   * @throws IOException if an error occurs during an I/O operation.
+   */
+  public void close()
+    throws IOException
+  {
+    // Nothing to do here.
+    super.close();
+  }
+
+  /**
+   * Reads in GZIP-compressed data and stores it in uncompressed form
+   * into an array of bytes.  The method will block until either
+   * enough input data becomes available or the compressed stream
+   * reaches its end.
+   *
+   * @param buf the buffer into which the uncompressed data will
+   *            be stored.
+   * @param offset the offset indicating where in <code>buf</code>
+   *               the uncompressed data should be placed.
+   * @param len the number of uncompressed bytes to be read.
+   */
+  public int read(byte[] buf, int offset, int len) throws IOException
+  {
+    // We first have to slurp in the GZIP header, then we feed all the
+    // rest of the data to the superclass.
+    //
+    // As we do that we continually update the CRC32. Once the data is
+    // finished, we check the CRC32.
+    //
+    // This means we don't need our own buffer, as everything is done
+    // in the superclass.
+    if (!readGZIPHeader)
+      readHeader();
+
+    if (eos)
+      return -1;
+
+    //  System.err.println("GZIPIS.read(byte[], off, len ... " + offset + " and len " + len);
+
+    /* We don't have to read the header,
+     * so we just grab data from the superclass.
+     */
+    int numRead = super.read(buf, offset, len);
+    if (numRead > 0)
+      crc.update(buf, offset, numRead);
+
+    if (inf.finished())
+      readFooter();
+    return numRead;
+  }
+
+
+  /**
+   * Reads in the GZIP header.
+   */
+  private void readHeader() throws IOException
+  {
+    /* 1. Check the two magic bytes */
+    CRC32 headCRC = new CRC32();
+    int magic = in.read();
+    if (magic < 0)
+    {
+      eos = true;
+      return;
+    }
+    int magic2 = in.read();
+    if ((magic + (magic2 << 8)) != GZIP_MAGIC)
+      throw new IOException("Error in GZIP header, bad magic code");
+    headCRC.update(magic);
+    headCRC.update(magic2);
+    
+    /* 2. Check the compression type (must be 8) */
+    int CM = in.read();
+    if (CM != 8)
+      throw new IOException("Error in GZIP header, data not in deflate format");
+    headCRC.update(CM);
+
+    /* 3. Check the flags */
+    int flags = in.read();
+    if (flags < 0)
+      throw new EOFException("Early EOF in GZIP header");
+    headCRC.update(flags);
+    
+    /*    This flag byte is divided into individual bits as follows:
+	  
+	  bit 0   FTEXT
+	  bit 1   FHCRC
+	  bit 2   FEXTRA
+	  bit 3   FNAME
+	  bit 4   FCOMMENT
+	  bit 5   reserved
+	  bit 6   reserved
+	  bit 7   reserved
+    */
+    
+    /* 3.1 Check the reserved bits are zero */    
+    if ((flags & 0xd0) != 0)
+      throw new IOException("Reserved flag bits in GZIP header != 0");
+    
+    /* 4.-6. Skip the modification time, extra flags, and OS type */
+    for (int i=0; i< 6; i++)
+    {
+      int readByte = in.read();
+      if (readByte < 0)
+	throw new EOFException("Early EOF in GZIP header");
+      headCRC.update(readByte);
+    }
+    
+    /* 7. Read extra field */
+    if ((flags & FEXTRA) != 0)
+    {
+      /* Skip subfield id */
+      for (int i=0; i< 2; i++)
+      {
+        int readByte = in.read();
+	if (readByte < 0)
+	  throw new EOFException("Early EOF in GZIP header");
+	headCRC.update(readByte);
+      }
+      if (in.read() < 0 || in.read() < 0)
+	throw new EOFException("Early EOF in GZIP header");
+	
+      int len1, len2, extraLen;
+      len1 = in.read();
+      len2 = in.read();
+      if ((len1 < 0) || (len2 < 0))
+	throw new EOFException("Early EOF in GZIP header");
+      headCRC.update(len1);
+      headCRC.update(len2);
+
+      extraLen = (len1 << 8) | len2;
+      for (int i = 0; i < extraLen;i++)
+      {
+	int readByte = in.read();
+	if (readByte < 0)
+	  throw new EOFException("Early EOF in GZIP header");
+	headCRC.update(readByte);
+      }
+    }
+    
+    /* 8. Read file name */
+    if ((flags & FNAME) != 0)
+    {
+      int readByte;
+      while ( (readByte = in.read()) > 0)
+	headCRC.update(readByte);
+      if (readByte < 0)
+	throw new EOFException("Early EOF in GZIP file name");
+      headCRC.update(readByte);
+    }
+
+    /* 9. Read comment */
+    if ((flags & FCOMMENT) != 0)
+    {
+      int readByte;
+      while ( (readByte = in.read()) > 0)
+        headCRC.update(readByte);
+
+      if (readByte < 0)
+        throw new EOFException("Early EOF in GZIP comment");
+      headCRC.update(readByte);
+    }
+    
+    /* 10. Read header CRC */
+    if ((flags & FHCRC) != 0)
+    {
+      int tempByte;
+      int crcval = in.read();
+      if (crcval < 0)
+        throw new EOFException("Early EOF in GZIP header");
+	
+      tempByte = in.read();
+      if (tempByte < 0)
+        throw new EOFException("Early EOF in GZIP header");
+	
+      crcval = (crcval << 8) | tempByte;
+      if (crcval != ((int) headCRC.getValue() & 0xffff))
+        throw new IOException("Header CRC value mismatch");
+    }
+    
+    readGZIPHeader = true;
+    //System.err.println("Read GZIP header");
+  }
+
+  private void readFooter() throws IOException
+  {
+    byte[] footer = new byte[8];
+    int avail = inf.getRemaining();
+    if (avail > 8)
+      avail = 8;
+    System.arraycopy(buf, len - inf.getRemaining(), footer, 0, avail);
+    int needed = 8 - avail;
+    while (needed > 0)
+    {
+      int count = in.read(footer, 8-needed, needed);
+      if (count <= 0)
+	throw new EOFException("Early EOF in GZIP footer");
+      needed -= count; //Jewel Jan 16
+    }
+
+    int crcval = (footer[0] & 0xff) | ((footer[1] & 0xff) << 8)
+      | ((footer[2] & 0xff) << 16) | (footer[3] << 24);
+    if (crcval != (int) crc.getValue())
+      throw new IOException("GZIP crc sum mismatch, theirs \""
+			    + Integer.toHexString(crcval)
+			    + "\" and ours \""
+			    + Integer.toHexString( (int) crc.getValue()));
+
+    int total = (footer[4] & 0xff) | ((footer[5] & 0xff) << 8)
+      | ((footer[6] & 0xff) << 16) | (footer[7] << 24);
+    if (total != inf.getTotalOut())
+      throw new IOException("Number of bytes mismatch");
+
+    /* FIXME" XXX Should we support multiple members.
+     * Difficult, since there may be some bytes still in buf
+     */
+    eos = true;
+  }
+}