1 /*
2 * Copyright (c) 2005, 2014, 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
26 package sun.tools.attach;
27
28 import com.sun.tools.attach.VirtualMachine;
29 import com.sun.tools.attach.AgentLoadException;
30 import com.sun.tools.attach.AgentInitializationException;
31 import com.sun.tools.attach.spi.AttachProvider;
32
33 import java.io.BufferedReader;
34 import java.io.InputStream;
35 import java.io.IOException;
36 import java.io.InputStreamReader;
37 import java.util.Properties;
38 import java.util.stream.Collectors;
39
40 /*
41 * The HotSpot implementation of com.sun.tools.attach.VirtualMachine.
42 */
43
44 public abstract class HotSpotVirtualMachine extends VirtualMachine {
45
46 HotSpotVirtualMachine(AttachProvider provider, String id) {
47 super(provider, id);
48 }
49
50 /*
51 * Load agent library
52 * If isAbsolute is true then the agent library is the absolute path
53 * to the library and thus will not be expanded in the target VM.
54 * if isAbsolute is false then the agent library is just a library
55 * name and it will be expended in the target VM.
56 */
57 private void loadAgentLibrary(String agentLibrary, boolean isAbsolute, String options)
58 throws AgentLoadException, AgentInitializationException, IOException
59 {
60 InputStream in = execute("load",
61 agentLibrary,
62 isAbsolute ? "true" : "false",
63 options);
64 try {
65 int result = readInt(in);
66 if (result != 0) {
67 throw new AgentInitializationException("Agent_OnAttach failed", result);
68 }
69 } finally {
70 in.close();
71
72 }
73 }
74
75 /*
76 * Load agent library - library name will be expanded in target VM
77 */
78 public void loadAgentLibrary(String agentLibrary, String options)
79 throws AgentLoadException, AgentInitializationException, IOException
80 {
81 loadAgentLibrary(agentLibrary, false, options);
82 }
83
84 /*
85 * Load agent - absolute path of library provided to target VM
86 */
87 public void loadAgentPath(String agentLibrary, String options)
88 throws AgentLoadException, AgentInitializationException, IOException
89 {
90 loadAgentLibrary(agentLibrary, true, options);
91 }
92
93 /*
94 * Load JPLIS agent which will load the agent JAR file and invoke
95 * the agentmain method.
96 */
97 public void loadAgent(String agent, String options)
98 throws AgentLoadException, AgentInitializationException, IOException
99 {
100 String args = agent;
101 if (options != null) {
102 args = args + "=" + options;
103 }
104 try {
105 loadAgentLibrary("instrument", args);
106 } catch (AgentLoadException x) {
107 throw new InternalError("instrument library is missing in target VM", x);
108 } catch (AgentInitializationException x) {
109 /*
110 * Translate interesting errors into the right exception and
111 * message (FIXME: create a better interface to the instrument
112 * implementation so this isn't necessary)
113 */
114 int rc = x.returnValue();
115 switch (rc) {
116 case JNI_ENOMEM:
117 throw new AgentLoadException("Insuffient memory");
118 case ATTACH_ERROR_BADJAR:
119 throw new AgentLoadException("Agent JAR not found or no Agent-Class attribute");
120 case ATTACH_ERROR_NOTONCP:
121 throw new AgentLoadException("Unable to add JAR file to system class path");
122 case ATTACH_ERROR_STARTFAIL:
123 throw new AgentInitializationException("Agent JAR loaded but agent failed to initialize");
124 default :
125 throw new AgentLoadException("Failed to load agent - unknown reason: " + rc);
126 }
127 }
128 }
129
130 /*
131 * The possible errors returned by JPLIS's agentmain
132 */
133 private static final int JNI_ENOMEM = -4;
134 private static final int ATTACH_ERROR_BADJAR = 100;
135 private static final int ATTACH_ERROR_NOTONCP = 101;
136 private static final int ATTACH_ERROR_STARTFAIL = 102;
137
138
139 /*
140 * Send "properties" command to target VM
141 */
142 public Properties getSystemProperties() throws IOException {
143 InputStream in = null;
144 Properties props = new Properties();
145 try {
146 in = executeCommand("properties");
147 props.load(in);
148 } finally {
149 if (in != null) in.close();
150 }
151 return props;
152 }
153
154 public Properties getAgentProperties() throws IOException {
155 InputStream in = null;
156 Properties props = new Properties();
157 try {
158 in = executeCommand("agentProperties");
159 props.load(in);
160 } finally {
161 if (in != null) in.close();
162 }
163 return props;
164 }
165
166 private static final String MANAGMENT_PREFIX = "com.sun.management.";
167
168 private static boolean checkedKeyName(Object key) {
169 if (!(key instanceof String)) {
170 throw new IllegalArgumentException("Invalid option (not a String): "+key);
171 }
172 if (!((String)key).startsWith(MANAGMENT_PREFIX)) {
173 throw new IllegalArgumentException("Invalid option: "+key);
174 }
175 return true;
176 }
177
178 private static String stripKeyName(Object key) {
179 return ((String)key).substring(MANAGMENT_PREFIX.length());
180 }
181
182 @Override
183 public void startManagementAgent(Properties agentProperties) throws IOException {
184 if (agentProperties == null) {
185 throw new NullPointerException("agentProperties cannot be null");
186 }
187 // Convert the arguments into arguments suitable for the Diagnostic Command:
188 // "ManagementAgent.start jmxremote.port=5555 jmxremote.authenticate=false"
189 String args = agentProperties.entrySet().stream()
190 .filter(entry -> checkedKeyName(entry.getKey()))
191 .map(entry -> stripKeyName(entry.getKey()) + "=" + escape(entry.getValue()))
192 .collect(Collectors.joining(" "));
193 executeJCmd("ManagementAgent.start " + args).close();
194 }
195
196 private String escape(Object arg) {
197 String value = arg.toString();
198 if (value.contains(" ")) {
199 return "'" + value + "'";
200 }
201 return value;
202 }
203
204 @Override
205 public String startLocalManagementAgent() throws IOException {
206 executeJCmd("ManagementAgent.start_local").close();
207 return getAgentProperties().getProperty("com.sun.management.jmxremote.localConnectorAddress");
208 }
209
210 // --- HotSpot specific methods ---
211
212 // same as SIGQUIT
213 public void localDataDump() throws IOException {
214 executeCommand("datadump").close();
215 }
216
217 // Remote ctrl-break. The output of the ctrl-break actions can
218 // be read from the input stream.
219 public InputStream remoteDataDump(Object ... args) throws IOException {
220 return executeCommand("threaddump", args);
221 }
222
223 // Remote heap dump. The output (error message) can be read from the
224 // returned input stream.
225 public InputStream dumpHeap(Object ... args) throws IOException {
226 return executeCommand("dumpheap", args);
227 }
228
229 // Heap histogram (heap inspection in HotSpot)
230 public InputStream heapHisto(Object ... args) throws IOException {
231 return executeCommand("inspectheap", args);
232 }
233
234 // set JVM command line flag
235 public InputStream setFlag(String name, String value) throws IOException {
236 return executeCommand("setflag", name, value);
237 }
238
239 // print command line flag
240 public InputStream printFlag(String name) throws IOException {
241 return executeCommand("printflag", name);
242 }
243
244 public InputStream executeJCmd(String command) throws IOException {
245 return executeCommand("jcmd", command);
246 }
247
248 // -- Supporting methods
249
250
251 /*
252 * Execute the given command in the target VM - specific platform
253 * implementation must implement this.
254 */
255 abstract InputStream execute(String cmd, Object ... args)
256 throws AgentLoadException, IOException;
257
258 /*
259 * Convenience method for simple commands
260 */
261 public InputStream executeCommand(String cmd, Object ... args) throws IOException {
262 try {
263 return execute(cmd, args);
264 } catch (AgentLoadException x) {
265 throw new InternalError("Should not get here", x);
266 }
267 }
268
269
270 /*
271 * Utility method to read an 'int' from the input stream. Ideally
272 * we should be using java.util.Scanner here but this implementation
273 * guarantees not to read ahead.
274 */
275 int readInt(InputStream in) throws IOException {
276 StringBuilder sb = new StringBuilder();
277
278 // read to \n or EOF
279 int n;
280 byte buf[] = new byte[1];
281 do {
282 n = in.read(buf, 0, 1);
283 if (n > 0) {
284 char c = (char)buf[0];
285 if (c == '\n') {
286 break; // EOL found
287 } else {
288 sb.append(c);
289 }
290 }
291 } while (n > 0);
292
293 if (sb.length() == 0) {
294 throw new IOException("Premature EOF");
295 }
296
297 int value;
298 try {
299 value = Integer.parseInt(sb.toString());
300 } catch (NumberFormatException x) {
301 throw new IOException("Non-numeric value found - int expected");
302 }
303 return value;
304 }
305
306 /*
307 * Utility method to read data into a String.
308 */
309 String readErrorMessage(InputStream sis) throws IOException {
310 String s;
311 StringBuilder message = new StringBuilder();
312 BufferedReader br = new BufferedReader(new InputStreamReader(sis));
313 while ((s = br.readLine()) != null) {
314 message.append(s);
315 }
316 return message.toString();
317 }
318
319
320 // -- attach timeout support
321
322 private static long defaultAttachTimeout = 5000;
323 private volatile long attachTimeout;
324
325 /*
326 * Return attach timeout based on the value of the sun.tools.attach.attachTimeout
327 * property, or the default timeout if the property is not set to a positive
328 * value.
329 */
330 long attachTimeout() {
331 if (attachTimeout == 0) {
332 synchronized(this) {
333 if (attachTimeout == 0) {
334 try {
335 String s =
336 System.getProperty("sun.tools.attach.attachTimeout");
337 attachTimeout = Long.parseLong(s);
338 } catch (SecurityException se) {
339 } catch (NumberFormatException ne) {
340 }
341 if (attachTimeout <= 0) {
342 attachTimeout = defaultAttachTimeout;
343 }
344 }
345 }
346 }
347 return attachTimeout;
348 }
349 }