obtained gcc-4.6.4.tar.bz2 from upstream website;upstream

verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
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if you have obtained the source via the command 'git clone',
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1 files changed, 283 insertions, 0 deletions

diff --git a/libjava/classpath/gnu/javax/imageio/png/PNGChunk.java b/libjava/classpath/gnu/javax/imageio/png/PNGChunk.java
new file mode 100644
index 000000000..ade0999fe
--- /dev/null
+++ b/libjava/classpath/gnu/javax/imageio/png/PNGChunk.java
@@ -0,0 +1,283 @@
+/* PNGChunk.java -- Generic PNG chunk
+   Copyright (C) 2006 Free Software Foundation
+
+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 gnu.javax.imageio.png;
+
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.IOException;
+
+/**
+ * Class to load and validate a generic PNG chunk.
+ */
+public class PNGChunk
+{
+
+  /**
+   * CRC table and initialization code.
+   */
+  private static long[] crcTable;
+
+  static
+   {
+     long c;
+     crcTable = new long[256];
+
+     for(int i = 0; i < 256; i++)
+       {
+         c = i;
+         for(int j = 0; j < 8; j++)
+           if( (c & 1) == 1 )
+             c = 0xEDB88320L ^ (c >> 1);
+           else
+             c = c >> 1;
+         crcTable[i] = c;
+       }
+   }
+
+  /**
+   * (recognized) PNG chunk types.
+   */
+  public static final int TYPE_HEADER = 0x49484452; // 'IHDR'
+  public static final int TYPE_PALETTE = 0x504c5445;// 'PLTE'
+  public static final int TYPE_DATA = 0x49444154;   // 'IDAT'
+  public static final int TYPE_TIME = 0x74494d45;   // 'tIME'
+  public static final int TYPE_END = 0x49454e44;    // 'IEND'
+  public static final int TYPE_PHYS = 0x70485973;   // 'pHYS'
+  public static final int TYPE_GAMMA = 0x67414d41;  // 'gAMA'
+  public static final int TYPE_PROFILE = 0x69434350;  // 'iCCP'
+
+  /**
+   * The chunk type - Represented in the file as 4 ASCII bytes,
+   */
+  private int type;
+
+  /**
+   * The chunk data
+   */
+  protected byte[] data;
+
+  /**
+   * The chunk's crc
+   */
+  private int crc;
+
+  /**
+   * Constructor for reading a generic chunk.
+   */
+  protected PNGChunk( int type, byte[] data, int crc )
+  {
+    this.type = type;
+    this.data = data;
+    this.crc = crc;
+  }
+
+  /**
+   * Constructor for creating new chunks.
+   * (only used by subclasses - creating a generic chunk is rather useless)
+   */
+  protected PNGChunk( int type )
+  {
+    this.type = type;
+  }
+
+  /**
+   * Loads a chunk from an InputStream. Does not perform validation,
+   * but will throw an IOException if the read fails.
+   * @param in - th einputstream to read from
+   * @param strict - if true, a PNGException is thrown on all invalid chunks,
+   * if false, only critical chunks will throw PNGExceptions.
+   */
+  public static PNGChunk readChunk(InputStream in, boolean strict)
+    throws IOException, PNGException
+  {
+    byte data[] = new byte[4];
+    if( in.read( data ) != 4 )
+      throw new IOException("Could not read chunk length.");
+    int length = ((data[0] & 0xFF) << 24) | ((data[1] & 0xFF) << 16 ) |
+      ((data[2] & 0xFF) << 8) | (data[3] & 0xFF);
+
+    if( in.read( data ) != 4 )
+      throw new IOException("Could not read chunk type.");
+    int type = ((data[0] & 0xFF) << 24) | ((data[1] & 0xFF) << 16 ) |
+      ((data[2] & 0xFF) << 8) | (data[3] & 0xFF);
+
+    byte[] chkdata = new byte[ length ];
+    if( in.read( chkdata ) != length )
+      throw new IOException("Could not read chunk data.");
+
+    if( in.read( data ) != 4 )
+      throw new IOException("Could not read chunk CRC.");
+
+    int crc = ((data[0] & 0xFF) << 24) | ( (data[1] & 0xFF) << 16 ) |
+      ((data[2] & 0xFF) << 8) | (data[3] & 0xFF);
+
+    if( strict )
+      return getChunk( type, chkdata, crc );
+    else
+      {
+        try
+          {
+            return getChunk( type, chkdata, crc );
+          }
+        catch(PNGException pnge)
+          {
+            if( isEssentialChunk( type ) )
+              throw pnge;
+            return null;
+          }
+      }
+  }
+
+  /**
+   * Returns a specialied object for a chunk, if we have one.
+   */
+  private static PNGChunk getChunk( int type, byte[] data, int crc )
+    throws PNGException
+  {
+    switch( type )
+      {
+      case TYPE_HEADER:
+        return new PNGHeader( type, data, crc );
+      case TYPE_DATA:
+        return new PNGData( type, data, crc );
+      case TYPE_PALETTE:
+        return new PNGPalette( type, data, crc );
+      case TYPE_TIME:
+        return new PNGTime( type, data, crc );
+      case TYPE_PHYS:
+        return new PNGPhys( type, data, crc );
+      case TYPE_GAMMA:
+        return new PNGGamma( type, data, crc );
+      case TYPE_PROFILE:
+        return new PNGICCProfile( type, data, crc );
+      default:
+        return new PNGChunk( type, data, crc );
+      }
+  }
+
+  /**
+   * Returns whether the chunk is essential or not
+   */
+  private static boolean isEssentialChunk( int type )
+  {
+    switch( type )
+      {
+      case TYPE_HEADER:
+      case TYPE_DATA:
+      case TYPE_PALETTE:
+      case TYPE_END:
+        return true;
+      default:
+        return false;
+      }
+  }
+
+  /**
+   * Validates the chunk
+   */
+  public boolean isValidChunk()
+  {
+    return (crc == calcCRC());
+  }
+
+  /**
+   * Returns the chunk type.
+   */
+  public int getType()
+  {
+    return type;
+  }
+
+  /**
+   * Writes a PNG chunk to an output stream,
+   * performing the CRC calculation as well.
+   */
+  public void writeChunk(OutputStream out) throws IOException
+  {
+    out.write( getInt(data.length) );
+    out.write( getInt(type) );
+    out.write( data );
+    out.write( getInt(calcCRC()) );
+  }
+
+  /**
+   * Return whether the chunk contains any data.
+   */
+  public boolean isEmpty()
+  {
+    return ( data.length == 0 );
+  }
+
+  /**
+   * Convenience method. Cast an int to four bytes (big endian).
+   * (Now why doesn't java have a simple way of doing this?)
+   */
+  public static byte[] getInt(int intValue)
+  {
+    long i = (intValue & 0xFFFFFFFFL);
+    byte[] b = new byte[4];
+    b[0] = (byte)((i & 0xFF000000L) >> 24);
+    b[1] = (byte)((i & 0x00FF0000L) >> 16);
+    b[2] = (byte)((i & 0x0000FF00L) >> 8);
+    b[3] = (byte)(i & 0x000000FFL);
+    return b;
+  }
+
+  /**
+   * Calculates this chunk's CRC value.
+   */
+  private int calcCRC()
+  {
+    long c = 0xFFFFFFFFL;
+    byte[] t = getInt( type );
+    for(int i = 0; i < 4; i++)
+      c = crcTable[ (int)((c ^ t[i]) & 0xFF) ] ^ (c >> 8);
+
+    for(int i = 0; i < data.length; i++)
+      c = crcTable[ (int)((c ^ data[i]) & 0xFF) ] ^ (c >> 8);
+
+    return (int)(c ^ 0xFFFFFFFFL);
+  }
+
+  public String toString()
+  {
+    return "PNG Chunk. Type: " + new String( getInt(type) ) + " , CRC: " +
+      crc + " , calculated CRC: "+calcCRC();
+  }
+
+}