| /* |
| * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package jdk.jshell.execution; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.ObjectInput; |
| import java.io.ObjectOutput; |
| import java.io.OutputStream; |
| import java.net.InetAddress; |
| import java.net.ServerSocket; |
| import java.net.Socket; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.function.Consumer; |
| import com.sun.jdi.BooleanValue; |
| import com.sun.jdi.ClassNotLoadedException; |
| import com.sun.jdi.Field; |
| import com.sun.jdi.IncompatibleThreadStateException; |
| import com.sun.jdi.InvalidTypeException; |
| import com.sun.jdi.ObjectReference; |
| import com.sun.jdi.StackFrame; |
| import com.sun.jdi.ThreadReference; |
| import com.sun.jdi.VMDisconnectedException; |
| import com.sun.jdi.VirtualMachine; |
| import jdk.jshell.spi.ExecutionControl; |
| import jdk.jshell.spi.ExecutionEnv; |
| import static jdk.jshell.execution.Util.remoteInputOutput; |
| |
| /** |
| * The implementation of {@link jdk.jshell.spi.ExecutionControl} that the |
| * JShell-core uses by default. |
| * Launches a remote process -- the "remote agent". |
| * Interfaces to the remote agent over a socket and via JDI. |
| * Designed to work with {@link RemoteExecutionControl}. |
| * |
| * @author Robert Field |
| * @author Jan Lahoda |
| * @since 9 |
| */ |
| public class JdiDefaultExecutionControl extends JdiExecutionControl { |
| |
| private VirtualMachine vm; |
| private Process process; |
| private final String remoteAgent; |
| |
| private final Object STOP_LOCK = new Object(); |
| private boolean userCodeRunning = false; |
| |
| /** |
| * Creates an ExecutionControl instance based on a JDI |
| * {@code ListeningConnector} or {@code LaunchingConnector}. |
| * |
| * Initialize JDI and use it to launch the remote JVM. Set-up a socket for |
| * commands and results. This socket also transports the user |
| * input/output/error. |
| * |
| * @param env the context passed by |
| * {@link jdk.jshell.spi.ExecutionControl#start(jdk.jshell.spi.ExecutionEnv) } |
| * @param remoteAgent the remote agent to launch |
| * @param isLaunch does JDI do the launch? That is, LaunchingConnector, |
| * otherwise we start explicitly and use ListeningConnector |
| * @param host explicit hostname to use, if null use discovered |
| * hostname, applies to listening only (!isLaunch) |
| * @return the channel |
| * @throws IOException if there are errors in set-up |
| */ |
| static ExecutionControl create(ExecutionEnv env, String remoteAgent, |
| boolean isLaunch, String host, int timeout) throws IOException { |
| try (final ServerSocket listener = new ServerSocket(0, 1, InetAddress.getLoopbackAddress())) { |
| // timeout on I/O-socket |
| listener.setSoTimeout(timeout); |
| int port = listener.getLocalPort(); |
| |
| // Set-up the JDI connection |
| JdiInitiator jdii = new JdiInitiator(port, |
| env.extraRemoteVMOptions(), remoteAgent, isLaunch, host, |
| timeout, Collections.emptyMap()); |
| VirtualMachine vm = jdii.vm(); |
| Process process = jdii.process(); |
| |
| List<Consumer<String>> deathListeners = new ArrayList<>(); |
| Util.detectJdiExitEvent(vm, s -> { |
| for (Consumer<String> h : deathListeners) { |
| h.accept(s); |
| } |
| }); |
| |
| // Set-up the commands/reslts on the socket. Piggy-back snippet |
| // output. |
| Socket socket = listener.accept(); |
| // out before in -- match remote creation so we don't hang |
| OutputStream out = socket.getOutputStream(); |
| Map<String, OutputStream> outputs = new HashMap<>(); |
| outputs.put("out", env.userOut()); |
| outputs.put("err", env.userErr()); |
| Map<String, InputStream> input = new HashMap<>(); |
| input.put("in", env.userIn()); |
| return remoteInputOutput(socket.getInputStream(), out, outputs, input, |
| (objIn, objOut) -> new JdiDefaultExecutionControl(env, |
| objOut, objIn, vm, process, remoteAgent, deathListeners)); |
| } |
| } |
| |
| /** |
| * Create an instance. |
| * |
| * @param cmdout the output for commands |
| * @param cmdin the input for responses |
| */ |
| private JdiDefaultExecutionControl(ExecutionEnv env, |
| ObjectOutput cmdout, ObjectInput cmdin, |
| VirtualMachine vm, Process process, String remoteAgent, |
| List<Consumer<String>> deathListeners) { |
| super(cmdout, cmdin); |
| this.vm = vm; |
| this.process = process; |
| this.remoteAgent = remoteAgent; |
| // We have now succeeded in establishing the connection. |
| // If there is an exit now it propagates all the way up |
| // and the VM should be disposed of. |
| deathListeners.add(s -> env.closeDown()); |
| deathListeners.add(s -> disposeVM()); |
| } |
| |
| @Override |
| public String invoke(String classname, String methodname) |
| throws RunException, |
| EngineTerminationException, InternalException { |
| String res; |
| synchronized (STOP_LOCK) { |
| userCodeRunning = true; |
| } |
| try { |
| res = super.invoke(classname, methodname); |
| } finally { |
| synchronized (STOP_LOCK) { |
| userCodeRunning = false; |
| } |
| } |
| return res; |
| } |
| |
| /** |
| * Interrupts a running remote invoke by manipulating remote variables |
| * and sending a stop via JDI. |
| * |
| * @throws EngineTerminationException the execution engine has terminated |
| * @throws InternalException an internal problem occurred |
| */ |
| @Override |
| public void stop() throws EngineTerminationException, InternalException { |
| synchronized (STOP_LOCK) { |
| if (!userCodeRunning) { |
| return; |
| } |
| |
| vm().suspend(); |
| try { |
| OUTER: |
| for (ThreadReference thread : vm().allThreads()) { |
| // could also tag the thread (e.g. using name), to find it easier |
| for (StackFrame frame : thread.frames()) { |
| if (remoteAgent.equals(frame.location().declaringType().name()) && |
| ( "invoke".equals(frame.location().method().name()) |
| || "varValue".equals(frame.location().method().name()))) { |
| ObjectReference thiz = frame.thisObject(); |
| Field inClientCode = thiz.referenceType().fieldByName("inClientCode"); |
| Field expectingStop = thiz.referenceType().fieldByName("expectingStop"); |
| Field stopException = thiz.referenceType().fieldByName("stopException"); |
| if (((BooleanValue) thiz.getValue(inClientCode)).value()) { |
| thiz.setValue(expectingStop, vm().mirrorOf(true)); |
| ObjectReference stopInstance = (ObjectReference) thiz.getValue(stopException); |
| |
| vm().resume(); |
| debug("Attempting to stop the client code...\n"); |
| thread.stop(stopInstance); |
| thiz.setValue(expectingStop, vm().mirrorOf(false)); |
| } |
| |
| break OUTER; |
| } |
| } |
| } |
| } catch (ClassNotLoadedException | IncompatibleThreadStateException | InvalidTypeException ex) { |
| throw new InternalException("Exception on remote stop: " + ex); |
| } finally { |
| vm().resume(); |
| } |
| } |
| } |
| |
| @Override |
| public void close() { |
| super.close(); |
| disposeVM(); |
| } |
| |
| private synchronized void disposeVM() { |
| try { |
| if (vm != null) { |
| vm.dispose(); // This could NPE, so it is caught below |
| vm = null; |
| } |
| } catch (VMDisconnectedException ex) { |
| // Ignore if already closed |
| } catch (Throwable ex) { |
| debug(ex, "disposeVM"); |
| } finally { |
| if (process != null) { |
| process.destroy(); |
| process = null; |
| } |
| } |
| } |
| |
| @Override |
| protected synchronized VirtualMachine vm() throws EngineTerminationException { |
| if (vm == null) { |
| throw new EngineTerminationException("VM closed"); |
| } else { |
| return vm; |
| } |
| } |
| |
| /** |
| * Log debugging information. Arguments as for {@code printf}. |
| * |
| * @param format a format string as described in Format string syntax |
| * @param args arguments referenced by the format specifiers in the format |
| * string. |
| */ |
| private static void debug(String format, Object... args) { |
| // Reserved for future logging |
| } |
| |
| /** |
| * Log a serious unexpected internal exception. |
| * |
| * @param ex the exception |
| * @param where a description of the context of the exception |
| */ |
| private static void debug(Throwable ex, String where) { |
| // Reserved for future logging |
| } |
| |
| } |