1 files changed, 277 insertions, 0 deletions
diff --git a/libjava/classpath/gnu/classpath/jdwp/transport/JdwpPacket.java b/libjava/classpath/gnu/classpath/jdwp/transport/JdwpPacket.java
new file mode 100644
index 000000000..b967d9bc5
--- /dev/null
+++ b/libjava/classpath/gnu/classpath/jdwp/transport/JdwpPacket.java
@@ -0,0 +1,277 @@
+/* JdwpPacket.java -- Base class for JDWP command and reply packets
+   Copyright (C) 2005 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
+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.classpath.jdwp.transport;
+
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+/**
+ * All command and reply packets in JDWP share
+ * common header type information:
+ *
+ *    length (4 bytes) : size of entire packet, including length
+ *    id     (4 bytes) : unique packet id
+ *    flags  (1 byte)  : flag byte
+ *    [command packet stuff | reply packet stuff]
+ *    data   (variable) : unique command-/reply-specific data
+ *
+ * This class deal with everything except the command- and reply-specific
+ * data, which get handled in {@link
+ * gnu.classpath.jdwp.transport.JdwpCommandPacket} and {@link
+ * gnu.classpath.jdwp.transport.JdwpReplyPacket}.
+ *
+ * @author Keith Seitz  <keiths@redhat.com>
+ */
+public abstract class JdwpPacket
+{
+  // Last id of packet constructed
+  protected static int _last_id = 0;
+
+  // JDWP reply packet flag
+  protected static final int JDWP_FLAG_REPLY = 0x80;
+
+  /**
+   * Minimum packet size excluding sub-class data
+   * ( length (4) + id (4) + flags (1) )
+   */
+  protected static final int MINIMUM_SIZE = 9;
+
+  /**
+   * Id of command/reply
+   */
+  protected int _id;
+
+  /**
+   * Packet flags
+   */
+  protected byte _flags;
+
+  /**
+   * Packet-specific data
+   */
+  protected byte[] _data;
+
+  /**
+   * Constructor
+   */
+  public JdwpPacket ()
+  {
+    // By default, DON'T assign an id. This way when a packet
+    // is constructed from fromBytes, _last_id won't increment (i.e.,
+    // it won't leave holes in the outgoing packet ids).
+  }
+
+  /**
+   * Constructs a <code>JdwpPacket</code> with the id
+   * from the given packet.
+   *
+   * @param pkt  a packet whose id will be used in this new packet
+   */
+  public JdwpPacket (JdwpPacket pkt)
+  {
+    _id = pkt.getId ();
+  }
+
+  /**
+   * Returns the packet id
+   */
+  public int getId ()
+  {
+    return _id;
+  }
+
+  /**
+   * Sets the packet id
+   */
+  public void setId (int id)
+  {
+    _id = id;
+  }
+
+  /**
+   * Returns the packet flags
+   */
+  public byte getFlags ()
+  {
+    return _flags;
+  }
+
+  /**
+   * Sets the packet flags
+   */
+  public void setFlags (byte flags)
+  {
+    _flags = flags;
+  }
+
+  /**
+   * Gets the command/reply-specific data in this packet
+   */
+  public byte[] getData ()
+  {
+    return _data;
+  }
+
+  /**
+   * Sets the command/reply-specific data in this packet
+   */
+  public void setData (byte[] data)
+  {
+    _data = data;
+  }
+
+  /**
+   * Returns the length of this entire packet
+   */
+  public int getLength ()
+  {
+    return MINIMUM_SIZE + (_data == null ? 0 : _data.length);
+  }
+
+  /**
+   * Allow subclasses to initialize from data
+   *
+   * @param   bytes  packet data from the wire
+   * @param   index  index into <code>bytes</code> to start processing
+   * @return         number of bytes in <code>bytes</code> processed
+   */
+  protected abstract int myFromBytes (byte[] bytes, int index);
+
+  /**
+   * Convert the given bytes into a <code>JdwpPacket</code>. Uses the
+   * abstract method <code>myFromBytes</code> to allow subclasses to
+   * process data.
+   *
+   * If the given data does not represent a valid JDWP packet, it returns
+   * <code>null</code>.
+   *
+   * @param   bytes  packet data from the wire
+   * @return         number of bytes in <code>bytes</code> processed
+   */
+  public static JdwpPacket fromBytes (byte[] bytes)
+  {
+    int i = 0;
+    int length = ((bytes[i++] & 0xff) << 24 | (bytes[i++] & 0xff) << 16
+                  | (bytes[i++] & 0xff) << 8 | (bytes[i++] & 0xff));
+    int id = 0;
+    byte flags = 0;
+
+    if (bytes.length == length)
+      {
+        id = ((bytes[i++] & 0xff) << 24 | (bytes[i++] & 0xff) << 16
+              | (bytes[i++] & 0xff) << 8 | (bytes[i++] & 0xff));
+        flags = bytes[i++];
+
+        Class clazz = null;
+        if (flags == 0)
+          clazz = JdwpCommandPacket.class;
+        else if ((flags & JDWP_FLAG_REPLY) != 0)
+          clazz = JdwpReplyPacket.class;
+        else
+          {
+            // Malformed packet. Discard it.
+            return null;
+          }
+
+        JdwpPacket pkt = null;
+        try
+          {
+            pkt = (JdwpPacket) clazz.newInstance ();
+          }
+        catch (InstantiationException ie)
+          {
+            // Discard packet
+            return null;
+          }
+        catch (IllegalAccessException iae)
+          {
+            // Discard packet
+            return null;
+          }
+
+        pkt.setId (id);
+        pkt.setFlags (flags);
+
+        i += pkt.myFromBytes (bytes, i);
+        byte[] data = new byte[length - i];
+        System.arraycopy (bytes, i, data, 0, data.length);
+        pkt.setData (data);
+
+        return pkt;
+      }
+
+    return null;
+  }
+
+  /**
+   * Put subclass information onto the stream
+   *
+   * @param dos the output stream to which to write
+   */
+  protected abstract void myWrite (DataOutputStream dos)
+    throws IOException;
+
+  /**
+   * Writes the packet to the output stream
+   *
+   * @param dos  the output stream to which to write the packet
+   */
+  public void write (DataOutputStream dos)
+    throws IOException
+  {
+    // length
+    int length = getLength ();
+    dos.writeInt (length);
+
+    // ID
+    dos.writeInt (getId ());
+
+    // flag
+    dos.writeByte (getFlags ());
+
+    // packet-specific stuff
+    myWrite (dos);
+
+    // data (if any)
+    byte[] data = getData ();
+    if (data != null && data.length > 0)
+      dos.write (data, 0, data.length);
+  }
+}