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 * @param useLocalhost explicitly use "localhost" rather than discovered
60 * hostname, applies to listening only (!isLaunch)
61 */
62 public JDIInitiator(int port, List<String> remoteVMOptions, String remoteAgent,
63 boolean isLaunch, boolean useLocalhost) {
64 this.remoteAgent = remoteAgent;
65 String connectorName
66 = isLaunch
67 ? "com.sun.jdi.CommandLineLaunch"
68 : "com.sun.jdi.SocketListen";
69 this.connector = findConnector(connectorName);
70 if (connector == null) {
71 throw new IllegalArgumentException("No connector named: " + connectorName);
72 }
73 Map<String, String> argumentName2Value
74 = isLaunch
75 ? launchArgs(port, String.join(" ", remoteVMOptions))
76 : new HashMap<>();
77 if (useLocalhost && !isLaunch) {
78 argumentName2Value.put("localAddress", "localhost");
79 }
80 this.connectorArgs = mergeConnectorArgs(connector, argumentName2Value);
81 this.vm = isLaunch
82 ? launchTarget()
83 : listenTarget(port, remoteVMOptions);
84
85 }
86
87 /**
88 * Returns the resulting {@code VirtualMachine} instance.
89 *
90 * @return the virtual machine
91 */
92 public VirtualMachine vm() {
93 return vm;
94 }
95
96 /**
97 * Returns the launched process.
98 *
99 * @return the remote agent process
100 */
101 public Process process() {
102 return process;
103 }
104
105 /* launch child target vm */
106 private VirtualMachine launchTarget() {
107 LaunchingConnector launcher = (LaunchingConnector) connector;
108 try {
109 VirtualMachine new_vm = launcher.launch(connectorArgs);
110 process = new_vm.process();
111 return new_vm;
112 } catch (Exception ex) {
113 reportLaunchFail(ex, "launch");
114 }
115 return null;
116 }
117
118 /**
119 * Directly launch the remote agent and connect JDI to it with a
120 * ListeningConnector.
121 */
122 private VirtualMachine listenTarget(int port, List<String> remoteVMOptions) {
123 ListeningConnector listener = (ListeningConnector) connector;
124 try {
125 // Start listening, get the JDI connection address
126 String addr = listener.startListening(connectorArgs);
127 debug("Listening at address: " + addr);
128
129 // Launch the RemoteAgent requesting a connection on that address
130 String javaHome = System.getProperty("java.home");
131 List<String> args = new ArrayList<>();
132 args.add(javaHome == null
133 ? "java"
134 : javaHome + File.separator + "bin" + File.separator + "java");
135 args.add("-agentlib:jdwp=transport=" + connector.transport().name() +
136 ",address=" + addr);
137 args.addAll(remoteVMOptions);
138 args.add(remoteAgent);
139 args.add("" + port);
140 ProcessBuilder pb = new ProcessBuilder(args);
141 process = pb.start();
142
143 // Forward out, err, and in
144 // Accept the connection from the remote agent
145 vm = listener.accept(connectorArgs);
146 listener.stopListening(connectorArgs);
147 return vm;
148 } catch (Exception ex) {
149 reportLaunchFail(ex, "listen");
150 }
151 return null;
152 }
153
154 private Connector findConnector(String name) {
155 for (Connector cntor
156 : Bootstrap.virtualMachineManager().allConnectors()) {
157 if (cntor.name().equals(name)) {
158 return cntor;
159 }
160 }
161 return null;
162 }
163
164 private Map<String, Connector.Argument> mergeConnectorArgs(Connector connector, Map<String, String> argumentName2Value) {
165 Map<String, Connector.Argument> arguments = connector.defaultArguments();
166
167 for (Entry<String, String> argumentEntry : argumentName2Value.entrySet()) {
168 String name = argumentEntry.getKey();
169 String value = argumentEntry.getValue();
170 Connector.Argument argument = arguments.get(name);
171
172 if (argument == null) {
173 throw new IllegalArgumentException("Argument is not defined for connector:" +
174 name + " -- " + connector.name());
175 }
176
177 argument.setValue(value);
178 }
179
180 return arguments;
181 }
182
183 /**
184 * The JShell specific Connector args for the LaunchingConnector.
185 *
186 * @param portthe socket port for (non-JDI) commands
187 * @param remoteVMOptions any user requested VM options
188 * @return the argument map
189 */
190 private Map<String, String> launchArgs(int port, String remoteVMOptions) {
191 Map<String, String> argumentName2Value = new HashMap<>();
192 argumentName2Value.put("main", remoteAgent + " " + port);
193 argumentName2Value.put("options", remoteVMOptions);
194 return argumentName2Value;
195 }
196
197 private void reportLaunchFail(Exception ex, String context) {
198 throw new InternalError("Failed remote " + context + ": " + connector +
199 " -- " + connectorArgs, ex);
200 }
201
202 /**
203 * Log debugging information. Arguments as for {@code printf}.
204 *
205 * @param format a format string as described in Format string syntax
206 * @param args arguments referenced by the format specifiers in the format
207 * string.
208 */
209 private void debug(String format, Object... args) {
210 // Reserved for future logging
211 }
212
213 /**
214 * Log a serious unexpected internal exception.
215 *
216 * @param ex the exception
217 * @param where a description of the context of the exception
218 */
219 private void debug(Throwable ex, String where) {
220 // Reserved for future logging
221 }
222
223 }