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Diffstat (limited to 'gcc-4.4.3/libjava/classpath/gnu/classpath/jdwp/transport/JdwpConnection.java')
| -rw-r--r-- | gcc-4.4.3/libjava/classpath/gnu/classpath/jdwp/transport/JdwpConnection.java | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/gnu/classpath/jdwp/transport/JdwpConnection.java b/gcc-4.4.3/libjava/classpath/gnu/classpath/jdwp/transport/JdwpConnection.java new file mode 100644 index 000000000..44158aa26 --- /dev/null +++ b/gcc-4.4.3/libjava/classpath/gnu/classpath/jdwp/transport/JdwpConnection.java @@ -0,0 +1,307 @@ +/* JdwpConnection.java -- A JDWP-speaking connection + Copyright (C) 2005, 2006, 2007 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 gnu.classpath.jdwp.Jdwp; +import gnu.classpath.jdwp.event.Event; +import gnu.classpath.jdwp.event.EventRequest; + +import java.io.ByteArrayOutputStream; +import java.io.DataInputStream; +import java.io.DataOutputStream; +import java.io.IOException; +import java.util.ArrayList; +import java.util.Arrays; + +/** + * A connection via some transport to some JDWP-speaking entity. + * This is also a thread which handles all communications to/from + * the debugger. While access to the transport layer may be accessed by + * several threads, start-up and initialization should not be allowed + * to occur more than once. + * + * <p>This class is also a thread that is responsible for pulling + * packets off the wire and sticking them in a queue for packet + * processing threads. + * + * @author Keith Seitz (keiths@redhat.com) + */ +public class JdwpConnection + extends Thread +{ + // The JDWP handshake + private static final byte[] _HANDSHAKE = {'J', 'D', 'W', 'P', '-', 'H', 'a', + 'n', 'd', 's', 'h', 'a', 'k', 'e'}; + + // Transport method + private ITransport _transport; + + // Command queue + private ArrayList _commandQueue; + + // Shutdown flag + private boolean _shutdown; + + // Input stream from transport + private DataInputStream _inStream; + + // Output stream from transprot + private DataOutputStream _outStream; + + // A buffer used to construct the packet data + private ByteArrayOutputStream _bytes; + + // A DataOutputStream for the byte buffer + private DataOutputStream _doStream; + + /** + * Creates a new <code>JdwpConnection</code> instance + * + * @param transport the transport to use for communications + */ + public JdwpConnection (ThreadGroup group, ITransport transport) + { + super (group, "JDWP connection thread"); + _transport = transport; + _commandQueue = new ArrayList (); + _shutdown = false; + _bytes = new ByteArrayOutputStream (); + _doStream = new DataOutputStream (_bytes); + } + + /** + * Initializes the connection, including connecting + * to socket or shared memory endpoint + * + * @throws TransportException if initialization fails + */ + public void initialize () + throws TransportException + { + // Initialize transport (connect socket, e.g.) + _transport.initialize (); + + // Do handshake + try + { + _inStream = new DataInputStream (_transport.getInputStream ()); + _outStream = new DataOutputStream (_transport.getOutputStream ()); + _doHandshake (); + } + catch (IOException ioe) + { + throw new TransportException (ioe); + } + } + + /* Does the JDWP handshake -- this should not need synchronization + because this is called by VM startup code, i.e., no packet + processing threads have started yet. */ + private void _doHandshake () + throws IOException + { + // According to the spec, the handshake is always initiated by + // the debugger, regardless of whether the JVM is in client mode or + // server mode. + + // Wait for handshake from debugger + byte[] hshake = new byte[_HANDSHAKE.length]; + _inStream.readFully (hshake, 0, _HANDSHAKE.length); + + if (Arrays.equals (hshake, _HANDSHAKE)) + { + // Send reply handshake + _outStream.write (_HANDSHAKE, 0, _HANDSHAKE.length); + return; + } + else + { + throw new IOException ("invalid JDWP handshake (\"" + hshake + "\")"); + } + } + + /** + * Main run method for the thread. This thread loops waiting for + * packets to be read via the connection. When a packet is complete + * and ready for processing, it places the packet in a queue that can + * be accessed via <code>getPacket</code> + */ + public void run () + { + // Notify initialization thread (gnu.classpath.jdwp.Jdwp) that + // the JdwpConnection thread is ready. + Jdwp.getDefault().subcomponentInitialized (); + + while (!_shutdown) + { + try + { + _readOnePacket (); + } + catch (IOException ioe) + { + /* IOException can occur for two reasons: + 1. Lost connection with the other side + 2. Transport was shutdown + In either case, we make sure that all of the + back-end gets shutdown. */ + Jdwp.getDefault().shutdown (); + } + catch (Throwable t) + { + System.out.println ("JdwpConnection.run: caught an exception: " + + t); + // Just keep going + } + } + } + + // Reads a single packet from the connection, adding it to the packet + // queue when a complete packet is ready. + private void _readOnePacket () + throws IOException + { + byte[] data = null; + + // Read in the packet + int length = _inStream.readInt (); + if (length < 11) + { + throw new IOException ("JDWP packet length < 11 (" + + length + ")"); + } + + data = new byte[length]; + data[0] = (byte) (length >>> 24); + data[1] = (byte) (length >>> 16); + data[2] = (byte) (length >>> 8); + data[3] = (byte) length; + _inStream.readFully (data, 4, length - 4); + + JdwpPacket packet = JdwpPacket.fromBytes (data); + if (packet != null) + { + synchronized (_commandQueue) + { + _commandQueue.add (packet); + _commandQueue.notifyAll (); + } + } + } + + /** + * Returns a packet from the queue of ready packets + * + * @returns a <code>JdwpPacket</code> ready for processing + * <code>null</code> when shutting down + */ + public JdwpPacket getPacket () + { + synchronized (_commandQueue) + { + while (_commandQueue.isEmpty ()) + { + try + { + _commandQueue.wait (); + } + catch (InterruptedException ie) + { + /* PacketProcessor is interrupted + when shutting down */ + return null; + } + } + + return (JdwpPacket) _commandQueue.remove (0); + } + } + + /** + * Send a packet to the debugger + * + * @param pkt a <code>JdwpPacket</code> to send + * @throws IOException + */ + public void sendPacket (JdwpPacket pkt) + throws IOException + { + pkt.write (_outStream); + } + + /** + * Send an event notification to the debugger. Note that this + * method will only send out one notification: all the events + * are passed in a single Event.COMPOSITE packet. + * + * @param requests debugger requests for events + * @param events the events to send + * @param suspendPolicy the suspend policy enforced by the VM + * @throws IOException + */ + public void sendEvents(EventRequest[] requests, Event[] events, + byte suspendPolicy) + throws IOException + { + JdwpPacket pkt; + + synchronized (_bytes) + { + _bytes.reset (); + pkt = Event.toPacket (_doStream, events, requests, suspendPolicy); + pkt.setData (_bytes.toByteArray ()); + } + + sendPacket (pkt); + } + + /** + * Shutdown the connection + */ + public void shutdown () + { + if (!_shutdown) + { + _transport.shutdown (); + _shutdown = true; + interrupt (); + } + } +} |