1 /*
2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package jdk.jshell.execution;
26
27 import java.io.File;
28 import java.util.ArrayList;
29 import java.util.HashMap;
30 import java.util.List;
31 import java.util.Map;
32 import java.util.Map.Entry;
33 import com.sun.jdi.Bootstrap;
34 import com.sun.jdi.VirtualMachine;
35 import com.sun.jdi.connect.Connector;
36 import com.sun.jdi.connect.LaunchingConnector;
37 import com.sun.jdi.connect.ListeningConnector;
38
39 /**
40 * Sets up a JDI connection, providing the resulting JDI {@link VirtualMachine}
41 * and the {@link Process} the remote agent is running in.
42 */
43 public class JDIInitiator {
44
45 private VirtualMachine vm;
46 private Process process = null;
47 private final Connector connector;
48 private final String remoteAgent;
49 private final Map<String, com.sun.jdi.connect.Connector.Argument> connectorArgs;
50
51 /**
52 * Start the remote agent and establish a JDI connection to it.
53 *
54 * @param port the socket port for (non-JDI) commands
55 * @param remoteVMOptions any user requested VM options
56 * @param remoteAgent full class name of remote agent to launch
57 * @param isLaunch does JDI do the launch? That is, LaunchingConnector,
58 * otherwise we start explicitly and use ListeningConnector
59 */
60 public JDIInitiator(int port, List<String> remoteVMOptions,
61 String remoteAgent, boolean isLaunch) {
62 this.remoteAgent = remoteAgent;
63 String connectorName
64 = isLaunch
65 ? "com.sun.jdi.CommandLineLaunch"
66 : "com.sun.jdi.SocketListen";
67 this.connector = findConnector(connectorName);
68 if (connector == null) {
69 throw new IllegalArgumentException("No connector named: " + connectorName);
70 }
71 Map<String, String> argumentName2Value
72 = isLaunch
73 ? launchArgs(port, String.join(" ", remoteVMOptions))
74 : new HashMap<>();
75 this.connectorArgs = mergeConnectorArgs(connector, argumentName2Value);
76 this.vm = isLaunch
77 ? launchTarget()
78 : listenTarget(port, remoteVMOptions);
79
80 }
81
82 /**
83 * Returns the resulting {@code VirtualMachine} instance.
84 *
85 * @return the virtual machine
86 */
87 public VirtualMachine vm() {
88 return vm;
89 }
90
91 /**
92 * Returns the launched process.
93 *
94 * @return the remote agent process
95 */
96 public Process process() {
97 return process;
98 }
99
100 /* launch child target vm */
101 private VirtualMachine launchTarget() {
102 LaunchingConnector launcher = (LaunchingConnector) connector;
103 try {
104 VirtualMachine new_vm = launcher.launch(connectorArgs);
105 process = new_vm.process();
106 return new_vm;
107 } catch (Exception ex) {
108 reportLaunchFail(ex, "launch");
109 }
110 return null;
111 }
112
113 /**
114 * Directly launch the remote agent and connect JDI to it with a
115 * ListeningConnector.
116 */
117 private VirtualMachine listenTarget(int port, List<String> remoteVMOptions) {
118 ListeningConnector listener = (ListeningConnector) connector;
119 try {
120 // Start listening, get the JDI connection address
121 String addr = listener.startListening(connectorArgs);
122 debug("Listening at address: " + addr);
123
124 // Launch the RemoteAgent requesting a connection on that address
125 String javaHome = System.getProperty("java.home");
126 List<String> args = new ArrayList<>();
127 args.add(javaHome == null
128 ? "java"
129 : javaHome + File.separator + "bin" + File.separator + "java");
130 args.add("-agentlib:jdwp=transport=" + connector.transport().name() +
131 ",address=" + addr);
132 args.addAll(remoteVMOptions);
133 args.add(remoteAgent);
134 args.add("" + port);
135 ProcessBuilder pb = new ProcessBuilder(args);
136 process = pb.start();
137
138 // Forward out, err, and in
139 // Accept the connection from the remote agent
140 vm = listener.accept(connectorArgs);
141 listener.stopListening(connectorArgs);
142 return vm;
143 } catch (Exception ex) {
144 reportLaunchFail(ex, "listen");
145 }
146 return null;
147 }
148
149 private Connector findConnector(String name) {
150 for (Connector cntor
151 : Bootstrap.virtualMachineManager().allConnectors()) {
152 if (cntor.name().equals(name)) {
153 return cntor;
154 }
155 }
156 return null;
157 }
158
159 private Map<String, Connector.Argument> mergeConnectorArgs(Connector connector, Map<String, String> argumentName2Value) {
160 Map<String, Connector.Argument> arguments = connector.defaultArguments();
161
162 for (Entry<String, String> argumentEntry : argumentName2Value.entrySet()) {
163 String name = argumentEntry.getKey();
164 String value = argumentEntry.getValue();
165 Connector.Argument argument = arguments.get(name);
166
167 if (argument == null) {
168 throw new IllegalArgumentException("Argument is not defined for connector:" +
169 name + " -- " + connector.name());
170 }
171
172 argument.setValue(value);
173 }
174
175 return arguments;
176 }
177
178 /**
179 * The JShell specific Connector args for the LaunchingConnector.
180 *
181 * @param portthe socket port for (non-JDI) commands
182 * @param remoteVMOptions any user requested VM options
183 * @return the argument map
184 */
185 private Map<String, String> launchArgs(int port, String remoteVMOptions) {
186 Map<String, String> argumentName2Value = new HashMap<>();
187 argumentName2Value.put("main", remoteAgent + " " + port);
188 argumentName2Value.put("options", remoteVMOptions);
189 return argumentName2Value;
190 }
191
192 private void reportLaunchFail(Exception ex, String context) {
193 throw new InternalError("Failed remote " + context + ": " + connector +
194 " -- " + connectorArgs, ex);
195 }
196
197 /**
198 * Log debugging information. Arguments as for {@code printf}.
199 *
200 * @param format a format string as described in Format string syntax
201 * @param args arguments referenced by the format specifiers in the format
202 * string.
203 */
204 private void debug(String format, Object... args) {
205 // Reserved for future logging
206 }
207
208 /**
209 * Log a serious unexpected internal exception.
210 *
211 * @param ex the exception
212 * @param where a description of the context of the exception
213 */
214 private void debug(Throwable ex, String where) {
215 // Reserved for future logging
216 }
217
218 }