[bug-classpath] [Bug classpath/23236] New: bug in ObjectInputStream

[jonathan dot shore at us dot hsbc dot com]

Bug caused garbled data to return when buffer is refreshed in certain 
circumstances:

- data item to be read spans two buffers (not enough bytes in current)

Bug is caused by:

- return value "length" is not the amount of bytes read, rather the length minus
amount read in previous buffer, should be total amount read

Fixed function as follows:

  public int read(byte[] data, int offset, int length) throws IOException
  {
    int read = 0;
    if (this.readDataFromBlock)
      {
        if (this.blockDataPosition + length > this.blockDataBytes)
          {
            int remain = this.blockDataBytes - this.blockDataPosition;
            if (remain != 0)
              {
                System.arraycopy(this.blockData, this.blockDataPosition,
                                 data, offset, remain);
                offset += remain;
                length -= remain;
                read += remain;
              }
            readNextBlock ();
          }

        // technically should check to see whether length bytes are available 
(possible
bug)
        System.arraycopy(this.blockData, this.blockDataPosition,
                         data, offset, length);
        this.blockDataPosition += length;
        read += length;
        return read;
      }
    else
      return this.realInputStream.read(data, offset, length);
  }

-- 
           Summary: bug in ObjectInputStream
           Product: classpath
           Version: unspecified
            Status: UNCONFIRMED
          Severity: critical
          Priority: P1
         Component: classpath
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jonathan dot shore at us dot hsbc dot com
                CC: bug-classpath at gnu dot org
 GCC build triplet: HEAD


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23236