trunk/libjava/classpath/gnu/classpath/jdwp/processor/StackFrameCommandSet.java

   1 /* StackFrameCommandSet.java -- class to implement the StackFrame Command Set
   2    Copyright (C) 2005, 2007 Free Software Foundation
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 terms of your choice, provided that you also meet, for each linked
  32 independent module, the terms and conditions of the license of that
  33 module.  An independent module is a module which is not derived from
  34 or based on this library.  If you modify this library, you may extend
  35 this exception to your version of the library, but you are not
  36 obligated to do so.  If you do not wish to do so, delete this
  37 exception statement from your version. */
  38
  39
  40 package gnu.classpath.jdwp.processor;
  41
  42 import gnu.classpath.jdwp.JdwpConstants;
  43 import gnu.classpath.jdwp.VMFrame;
  44 import gnu.classpath.jdwp.VMVirtualMachine;
  45 import gnu.classpath.jdwp.exception.JdwpException;
  46 import gnu.classpath.jdwp.exception.JdwpInternalErrorException;
  47 import gnu.classpath.jdwp.exception.NotImplementedException;
  48 import gnu.classpath.jdwp.id.ThreadId;
  49 import gnu.classpath.jdwp.value.ObjectValue;
  50 import gnu.classpath.jdwp.value.Value;
  51 import gnu.classpath.jdwp.value.ValueFactory;
  52
  53 import java.io.DataOutputStream;
  54 import java.io.IOException;
  55 import java.nio.ByteBuffer;
  56
  57 /**
  58  * A class representing the StackFrame Command Set.
  59  *
  60  * @author Aaron Luchko <aluchko@redhat.com>
  61  */
  62 public class StackFrameCommandSet
  63   extends CommandSet
  64 {
  65   public boolean runCommand(ByteBuffer bb, DataOutputStream os, byte command)
  66       throws JdwpException
  67   {
  68     boolean keepRunning = true;
  69     try
  70       {
  71         switch (command)
  72           {
  73           case JdwpConstants.CommandSet.StackFrame.GET_VALUES:
  74             executeGetValues(bb, os);
  75             break;
  76           case JdwpConstants.CommandSet.StackFrame.SET_VALUES:
  77             executeSetValues(bb, os);
  78             break;
  79           case JdwpConstants.CommandSet.StackFrame.THIS_OBJECT:
  80             executeThisObject(bb, os);
  81             break;
  82           case JdwpConstants.CommandSet.StackFrame.POP_FRAMES:
  83             executePopFrames(bb, os);
  84             break;
  85           default:
  86             throw new NotImplementedException("Command " + command +
  87             " not found in Stack Frame Command Set.");
  88           }
  89       }
  90     catch (IOException ex)
  91       {
  92         // The DataOutputStream we're using isn't talking to a socket at all
  93         // So if we throw an IOException we're in serious trouble
  94         throw new JdwpInternalErrorException(ex);
  95       }
  96
  97     return false;
  98   }
  99
 100   private void executeGetValues(ByteBuffer bb, DataOutputStream os)
 101       throws JdwpException, IOException
 102   {
 103     ThreadId tId = (ThreadId) idMan.readObjectId(bb);
 104     Thread thread = tId.getThread();
 105
 106     // Although Frames look like other ids they are not. First they are not
 107     // ObjectIds since they don't exist in the users code. Storing them as an
 108     // ObjectId would mean they could be garbage collected since no one else
 109     // has a reference to them. Furthermore they are not ReferenceTypeIds since
 110     // these are held permanently and we want these to be held only as long as
 111     // the Thread is suspended.
 112     long frameID = bb.getLong();
 113     VMFrame frame = VMVirtualMachine.getFrame(thread, frameID);
 114     int slots = bb.getInt();
 115     os.writeInt(slots); // Looks pointless but this is the protocol
 116     for (int i = 0; i < slots; i++)
 117       {
 118         int slot = bb.getInt();
 119         byte sig = bb.get();
 120         Value val = frame.getValue(slot, sig);
 121         val.writeTagged(os);
 122       }
 123   }
 124
 125   private void executeSetValues(ByteBuffer bb, DataOutputStream os)
 126       throws JdwpException, IOException
 127   {
 128     ThreadId tId = (ThreadId) idMan.readObjectId(bb);
 129     Thread thread = tId.getThread();
 130
 131     long frameID = bb.getLong();
 132     VMFrame frame = VMVirtualMachine.getFrame(thread, frameID);
 133
 134     int slots = bb.getInt();
 135     for (int i = 0; i < slots; i++)
 136       {
 137         int slot = bb.getInt();
 138         Value value = ValueFactory.createFromTagged(bb);
 139         frame.setValue(slot, value);
 140       }
 141   }
 142
 143   private void executeThisObject(ByteBuffer bb, DataOutputStream os)
 144       throws JdwpException, IOException
 145   {
 146     ThreadId tId = (ThreadId) idMan.readObjectId(bb);
 147     Thread thread = tId.getThread();
 148
 149     long frameID = bb.getLong();
 150     VMFrame frame = VMVirtualMachine.getFrame(thread, frameID);
 151
 152     ObjectValue objVal = new ObjectValue(frame.getObject());
 153     objVal.writeTagged(os);
 154   }
 155
 156   private void executePopFrames(ByteBuffer bb, DataOutputStream os)
 157     throws JdwpException, IOException
 158   {
 159     if (!VMVirtualMachine.canPopFrames)
 160       {
 161         String msg = "popping frames is unsupported";
 162         throw new NotImplementedException(msg);
 163       }
 164
 165     ThreadId tid = (ThreadId) idMan.readObjectId(bb);
 166     Thread thread = tid.getThread();
 167     long fid = bb.getLong();
 168     VMVirtualMachine.popFrames(thread, fid);
 169   }
 170 }