Commit | Line | Data |
---|---|---|
43e5396b | 1 | /* |
c0c0989a | 2 | * SPDX-License-Identifier: LGPL-2.1-only |
43e5396b | 3 | * |
c0c0989a MJ |
4 | * Copyright (C) 2015-2016 EfficiOS Inc. |
5 | * Copyright (C) 2015-2016 Alexandre Montplaisir <alexmonthy@efficios.com> | |
6 | * Copyright (C) 2013 David Goulet <dgoulet@efficios.com> | |
43e5396b DG |
7 | */ |
8 | ||
d60dfbe4 | 9 | package org.lttng.ust.agent.client; |
43e5396b | 10 | |
f1fa0535 | 11 | import java.io.BufferedReader; |
43e5396b | 12 | import java.io.DataInputStream; |
bc7de6d9 | 13 | import java.io.DataOutputStream; |
9f84d546 | 14 | import java.io.FileInputStream; |
f1fa0535 | 15 | import java.io.FileNotFoundException; |
bc7de6d9 | 16 | import java.io.IOException; |
9f84d546 | 17 | import java.io.InputStreamReader; |
43e5396b | 18 | import java.lang.management.ManagementFactory; |
bc7de6d9 AM |
19 | import java.net.Socket; |
20 | import java.net.UnknownHostException; | |
21 | import java.nio.ByteBuffer; | |
22 | import java.nio.ByteOrder; | |
9f84d546 | 23 | import java.nio.charset.Charset; |
d60dfbe4 AM |
24 | import java.util.concurrent.CountDownLatch; |
25 | import java.util.concurrent.TimeUnit; | |
43e5396b | 26 | |
cbe2ebd6 AM |
27 | import org.lttng.ust.agent.utils.LttngUstAgentLogger; |
28 | ||
d60dfbe4 AM |
29 | /** |
30 | * Client for agents to connect to a local session daemon, using a TCP socket. | |
31 | * | |
32 | * @author David Goulet | |
33 | */ | |
34 | public class LttngTcpSessiondClient implements Runnable { | |
43e5396b | 35 | |
08284556 AM |
36 | private static final String SESSION_HOST = "127.0.0.1"; |
37 | private static final String ROOT_PORT_FILE = "/var/run/lttng/agent.port"; | |
38 | private static final String USER_PORT_FILE = "/.lttng/agent.port"; | |
47fa3e4e | 39 | private static final String APP_PATH_PORT_FILE = "/agent.port"; |
9f84d546 | 40 | private static final Charset PORT_FILE_ENCODING = Charset.forName("UTF-8"); |
08284556 | 41 | |
191f4058 AM |
42 | private static final int PROTOCOL_MAJOR_VERSION = 2; |
43 | private static final int PROTOCOL_MINOR_VERSION = 0; | |
08284556 | 44 | |
2fbda51c | 45 | /** Command header from the session daemon. */ |
d60dfbe4 | 46 | private final CountDownLatch registrationLatch = new CountDownLatch(1); |
43e5396b | 47 | |
43e5396b | 48 | private Socket sessiondSock; |
501f6777 | 49 | private volatile boolean quit = false; |
43e5396b DG |
50 | |
51 | private DataInputStream inFromSessiond; | |
52 | private DataOutputStream outToSessiond; | |
53 | ||
3165c2f5 AM |
54 | private final ILttngTcpClientListener logAgent; |
55 | private final int domainValue; | |
d60dfbe4 | 56 | private final boolean isRoot; |
501f6777 | 57 | |
d60dfbe4 AM |
58 | /** |
59 | * Constructor | |
60 | * | |
61 | * @param logAgent | |
3165c2f5 AM |
62 | * The listener this client will operate on, typically an LTTng |
63 | * agent. | |
64 | * @param domainValue | |
65 | * The integer to send to the session daemon representing the | |
66 | * tracing domain to handle. | |
d60dfbe4 AM |
67 | * @param isRoot |
68 | * True if this client should connect to the root session daemon, | |
69 | * false if it should connect to the user one. | |
70 | */ | |
3165c2f5 | 71 | public LttngTcpSessiondClient(ILttngTcpClientListener logAgent, int domainValue, boolean isRoot) { |
d60dfbe4 | 72 | this.logAgent = logAgent; |
3165c2f5 | 73 | this.domainValue = domainValue; |
d60dfbe4 | 74 | this.isRoot = isRoot; |
43e5396b DG |
75 | } |
76 | ||
d60dfbe4 AM |
77 | /** |
78 | * Wait until this client has successfully established a connection to its | |
79 | * target session daemon. | |
80 | * | |
81 | * @param seconds | |
82 | * A timeout in seconds after which this method will return | |
83 | * anyway. | |
84 | * @return True if the the client actually established the connection, false | |
85 | * if we returned because the timeout has elapsed or the thread was | |
86 | * interrupted. | |
f1fa0535 | 87 | */ |
d60dfbe4 AM |
88 | public boolean waitForConnection(int seconds) { |
89 | try { | |
90 | return registrationLatch.await(seconds, TimeUnit.SECONDS); | |
91 | } catch (InterruptedException e) { | |
92 | return false; | |
f1fa0535 DG |
93 | } |
94 | } | |
95 | ||
501f6777 CB |
96 | @Override |
97 | public void run() { | |
43e5396b DG |
98 | for (;;) { |
99 | if (this.quit) { | |
100 | break; | |
101 | } | |
102 | ||
103 | try { | |
104 | ||
105 | /* | |
106 | * Connect to the session daemon before anything else. | |
107 | */ | |
6e1fdc3a | 108 | log("Connecting to sessiond"); |
43e5396b DG |
109 | connectToSessiond(); |
110 | ||
111 | /* | |
112 | * Register to the session daemon as the Java component of the | |
113 | * UST application. | |
114 | */ | |
6e1fdc3a | 115 | log("Registering to sessiond"); |
43e5396b | 116 | registerToSessiond(); |
43e5396b | 117 | |
43e5396b DG |
118 | /* |
119 | * Block on socket receive and wait for command from the | |
120 | * session daemon. This will return if and only if there is a | |
121 | * fatal error or the socket closes. | |
122 | */ | |
6e1fdc3a | 123 | log("Waiting on sessiond commands..."); |
43e5396b DG |
124 | handleSessiondCmd(); |
125 | } catch (UnknownHostException uhe) { | |
d60dfbe4 | 126 | uhe.printStackTrace(); |
35cbacdb MD |
127 | /* |
128 | * Terminate agent thread. | |
129 | */ | |
130 | close(); | |
43e5396b | 131 | } catch (IOException ioe) { |
35cbacdb MD |
132 | /* |
133 | * I/O exception may have been triggered by a session daemon | |
134 | * closing the socket. Close our own socket and | |
135 | * retry connecting after a delay. | |
136 | */ | |
501f6777 | 137 | try { |
35cbacdb MD |
138 | if (this.sessiondSock != null) { |
139 | this.sessiondSock.close(); | |
140 | } | |
501f6777 CB |
141 | Thread.sleep(3000); |
142 | } catch (InterruptedException e) { | |
35cbacdb MD |
143 | /* |
144 | * Retry immediately if sleep is interrupted. | |
145 | */ | |
146 | } catch (IOException closeioe) { | |
147 | closeioe.printStackTrace(); | |
148 | /* | |
149 | * Terminate agent thread. | |
150 | */ | |
151 | close(); | |
501f6777 | 152 | } |
43e5396b DG |
153 | } |
154 | } | |
155 | } | |
156 | ||
d60dfbe4 AM |
157 | /** |
158 | * Dispose this client and close any socket connection it may hold. | |
159 | */ | |
160 | public void close() { | |
6e1fdc3a | 161 | log("Closing client"); |
43e5396b | 162 | this.quit = true; |
43e5396b DG |
163 | |
164 | try { | |
165 | if (this.sessiondSock != null) { | |
166 | this.sessiondSock.close(); | |
167 | } | |
d60dfbe4 | 168 | } catch (IOException e) { |
43e5396b DG |
169 | e.printStackTrace(); |
170 | } | |
171 | } | |
172 | ||
301a3ddb | 173 | private void connectToSessiond() throws IOException { |
c0f6fb05 | 174 | int portToUse; |
e0c010a9 AM |
175 | |
176 | /* | |
c0f6fb05 MD |
177 | * The environment variable LTTNG_UST_APP_PATH disables |
178 | * connection to per-user and root session daemons. | |
e0c010a9 | 179 | */ |
c0f6fb05 MD |
180 | String lttngUstAppPath = getUstAppPath(); |
181 | ||
182 | if (lttngUstAppPath != null) { | |
47fa3e4e | 183 | portToUse = getPortFromFile(lttngUstAppPath + APP_PATH_PORT_FILE); |
c0f6fb05 MD |
184 | } else { |
185 | int rootPort = getPortFromFile(ROOT_PORT_FILE); | |
186 | int userPort = getPortFromFile(getHomePath() + USER_PORT_FILE); | |
187 | ||
188 | /* | |
189 | * Check for the edge case of both files existing but pointing to the | |
190 | * same port. In this case, let the root client handle it. | |
191 | */ | |
192 | if ((rootPort != 0) && (rootPort == userPort) && (!isRoot)) { | |
193 | log("User and root config files both point to port " + rootPort + | |
194 | ". Letting the root client handle it."); | |
195 | throw new IOException(); | |
196 | } | |
43e5396b | 197 | |
c0f6fb05 MD |
198 | portToUse = (isRoot ? rootPort : userPort); |
199 | } | |
e0c010a9 AM |
200 | |
201 | if (portToUse == 0) { | |
202 | /* No session daemon available. Stop and retry later. */ | |
203 | throw new IOException(); | |
43e5396b | 204 | } |
301a3ddb | 205 | |
e0c010a9 | 206 | this.sessiondSock = new Socket(SESSION_HOST, portToUse); |
301a3ddb AM |
207 | this.inFromSessiond = new DataInputStream(sessiondSock.getInputStream()); |
208 | this.outToSessiond = new DataOutputStream(sessiondSock.getOutputStream()); | |
209 | } | |
210 | ||
c0f6fb05 MD |
211 | private static String getUstAppPath() { |
212 | return System.getenv("LTTNG_UST_APP_PATH"); | |
213 | } | |
214 | ||
301a3ddb | 215 | private static String getHomePath() { |
59e3be47 MD |
216 | /* |
217 | * The environment variable LTTNG_HOME overrides HOME if | |
c0f6fb05 | 218 | * set. |
59e3be47 | 219 | */ |
c0f6fb05 MD |
220 | String lttngHomePath = System.getenv("LTTNG_HOME"); |
221 | if (lttngHomePath != null) { | |
222 | return lttngHomePath; | |
59e3be47 | 223 | } |
c0f6fb05 | 224 | return System.getProperty("user.home"); |
43e5396b DG |
225 | } |
226 | ||
d60dfbe4 | 227 | /** |
301a3ddb | 228 | * Read port number from file created by the session daemon. |
43e5396b | 229 | * |
301a3ddb | 230 | * @return port value if found else 0. |
43e5396b | 231 | */ |
301a3ddb | 232 | private static int getPortFromFile(String path) throws IOException { |
301a3ddb | 233 | BufferedReader br = null; |
43e5396b | 234 | |
301a3ddb | 235 | try { |
9f84d546 | 236 | br = new BufferedReader(new InputStreamReader(new FileInputStream(path), PORT_FILE_ENCODING)); |
301a3ddb | 237 | String line = br.readLine(); |
8d8c99c9 AM |
238 | if (line == null) { |
239 | /* File exists but is empty. */ | |
240 | return 0; | |
241 | } | |
242 | ||
243 | int port = Integer.parseInt(line, 10); | |
301a3ddb AM |
244 | if (port < 0 || port > 65535) { |
245 | /* Invalid value. Ignore. */ | |
246 | port = 0; | |
247 | } | |
8d8c99c9 AM |
248 | return port; |
249 | ||
250 | } catch (NumberFormatException e) { | |
251 | /* File contained something that was not a number. */ | |
252 | return 0; | |
301a3ddb AM |
253 | } catch (FileNotFoundException e) { |
254 | /* No port available. */ | |
8d8c99c9 | 255 | return 0; |
301a3ddb AM |
256 | } finally { |
257 | if (br != null) { | |
258 | br.close(); | |
259 | } | |
43e5396b | 260 | } |
301a3ddb AM |
261 | } |
262 | ||
263 | private void registerToSessiond() throws IOException { | |
264 | byte data[] = new byte[16]; | |
265 | ByteBuffer buf = ByteBuffer.wrap(data); | |
266 | String pid = ManagementFactory.getRuntimeMXBean().getName().split("@")[0]; | |
267 | ||
3165c2f5 | 268 | buf.putInt(domainValue); |
301a3ddb | 269 | buf.putInt(Integer.parseInt(pid)); |
191f4058 AM |
270 | buf.putInt(PROTOCOL_MAJOR_VERSION); |
271 | buf.putInt(PROTOCOL_MINOR_VERSION); | |
301a3ddb AM |
272 | this.outToSessiond.write(data, 0, data.length); |
273 | this.outToSessiond.flush(); | |
43e5396b DG |
274 | } |
275 | ||
d60dfbe4 | 276 | /** |
43e5396b DG |
277 | * Handle session command from the session daemon. |
278 | */ | |
d60dfbe4 | 279 | private void handleSessiondCmd() throws IOException { |
301a3ddb AM |
280 | /* Data read from the socket */ |
281 | byte inputData[] = null; | |
282 | /* Reply data written to the socket, sent to the sessiond */ | |
f35c6aa0 | 283 | LttngAgentResponse response; |
43e5396b DG |
284 | |
285 | while (true) { | |
286 | /* Get header from session daemon. */ | |
301a3ddb | 287 | SessiondCommandHeader cmdHeader = recvHeader(); |
43e5396b | 288 | |
301a3ddb AM |
289 | if (cmdHeader.getDataSize() > 0) { |
290 | inputData = recvPayload(cmdHeader); | |
43e5396b DG |
291 | } |
292 | ||
301a3ddb | 293 | switch (cmdHeader.getCommandType()) { |
d60dfbe4 AM |
294 | case CMD_REG_DONE: |
295 | { | |
296 | /* | |
297 | * Countdown the registration latch, meaning registration is | |
298 | * done and we can proceed to continue tracing. | |
299 | */ | |
300 | registrationLatch.countDown(); | |
301 | /* | |
302 | * We don't send any reply to the registration done command. | |
303 | * This just marks the end of the initial session setup. | |
304 | */ | |
6e1fdc3a | 305 | log("Registration done"); |
d60dfbe4 AM |
306 | continue; |
307 | } | |
308 | case CMD_LIST: | |
309 | { | |
1d193914 | 310 | SessiondCommand listLoggerCmd = new SessiondListLoggersCommand(); |
f35c6aa0 | 311 | response = listLoggerCmd.execute(logAgent); |
6e1fdc3a | 312 | log("Received list loggers command"); |
d60dfbe4 AM |
313 | break; |
314 | } | |
8ab5c06b | 315 | case CMD_EVENT_ENABLE: |
d60dfbe4 | 316 | { |
301a3ddb AM |
317 | if (inputData == null) { |
318 | /* Invalid command */ | |
f35c6aa0 | 319 | response = LttngAgentResponse.FAILURE_RESPONSE; |
43e5396b DG |
320 | break; |
321 | } | |
8ab5c06b | 322 | SessiondCommand enableEventCmd = new SessiondEnableEventCommand(inputData); |
f35c6aa0 AM |
323 | response = enableEventCmd.execute(logAgent); |
324 | log("Received enable event command: " + enableEventCmd.toString()); | |
d60dfbe4 AM |
325 | break; |
326 | } | |
8ab5c06b | 327 | case CMD_EVENT_DISABLE: |
d60dfbe4 | 328 | { |
301a3ddb AM |
329 | if (inputData == null) { |
330 | /* Invalid command */ | |
f35c6aa0 | 331 | response = LttngAgentResponse.FAILURE_RESPONSE; |
43e5396b DG |
332 | break; |
333 | } | |
8ab5c06b | 334 | SessiondCommand disableEventCmd = new SessiondDisableEventCommand(inputData); |
f35c6aa0 AM |
335 | response = disableEventCmd.execute(logAgent); |
336 | log("Received disable event command: " + disableEventCmd.toString()); | |
8ab5c06b AM |
337 | break; |
338 | } | |
339 | case CMD_APP_CTX_ENABLE: | |
340 | { | |
341 | if (inputData == null) { | |
342 | /* This commands expects a payload, invalid command */ | |
f35c6aa0 | 343 | response = LttngAgentResponse.FAILURE_RESPONSE; |
8ab5c06b AM |
344 | break; |
345 | } | |
346 | SessiondCommand enableAppCtxCmd = new SessiondEnableAppContextCommand(inputData); | |
f35c6aa0 | 347 | response = enableAppCtxCmd.execute(logAgent); |
6e1fdc3a | 348 | log("Received enable app-context command"); |
8ab5c06b AM |
349 | break; |
350 | } | |
351 | case CMD_APP_CTX_DISABLE: | |
352 | { | |
353 | if (inputData == null) { | |
354 | /* This commands expects a payload, invalid command */ | |
f35c6aa0 | 355 | response = LttngAgentResponse.FAILURE_RESPONSE; |
8ab5c06b AM |
356 | break; |
357 | } | |
358 | SessiondCommand disableAppCtxCmd = new SessiondDisableAppContextCommand(inputData); | |
f35c6aa0 | 359 | response = disableAppCtxCmd.execute(logAgent); |
6e1fdc3a | 360 | log("Received disable app-context command"); |
d60dfbe4 AM |
361 | break; |
362 | } | |
363 | default: | |
364 | { | |
301a3ddb | 365 | /* Unknown command, send empty reply */ |
f35c6aa0 | 366 | response = null; |
6e1fdc3a | 367 | log("Received unknown command, ignoring"); |
d60dfbe4 AM |
368 | break; |
369 | } | |
43e5396b DG |
370 | } |
371 | ||
301a3ddb | 372 | /* Send response to the session daemon. */ |
f35c6aa0 AM |
373 | byte[] responseData; |
374 | if (response == null) { | |
375 | responseData = new byte[4]; | |
376 | ByteBuffer buf = ByteBuffer.wrap(responseData); | |
377 | buf.order(ByteOrder.BIG_ENDIAN); | |
378 | } else { | |
379 | log("Sending response: " + response.toString()); | |
380 | responseData = response.getBytes(); | |
381 | } | |
301a3ddb | 382 | this.outToSessiond.write(responseData, 0, responseData.length); |
43e5396b DG |
383 | this.outToSessiond.flush(); |
384 | } | |
385 | } | |
386 | ||
f1fa0535 | 387 | /** |
301a3ddb AM |
388 | * Receive header data from the session daemon using the LTTng command |
389 | * static buffer of the right size. | |
f1fa0535 | 390 | */ |
301a3ddb AM |
391 | private SessiondCommandHeader recvHeader() throws IOException { |
392 | byte data[] = new byte[SessiondCommandHeader.HEADER_SIZE]; | |
32974710 MD |
393 | int bytesLeft = data.length; |
394 | int bytesOffset = 0; | |
f1fa0535 | 395 | |
dcd9a9d7 | 396 | while (bytesLeft > 0) { |
32974710 MD |
397 | int bytesRead = this.inFromSessiond.read(data, bytesOffset, bytesLeft); |
398 | ||
399 | if (bytesRead < 0) { | |
400 | throw new IOException(); | |
401 | } | |
402 | bytesLeft -= bytesRead; | |
403 | bytesOffset += bytesRead; | |
f1fa0535 | 404 | } |
301a3ddb | 405 | return new SessiondCommandHeader(data); |
f1fa0535 DG |
406 | } |
407 | ||
301a3ddb AM |
408 | /** |
409 | * Receive payload from the session daemon. This MUST be done after a | |
410 | * recvHeader() so the header value of a command are known. | |
411 | * | |
412 | * The caller SHOULD use isPayload() before which returns true if a payload | |
413 | * is expected after the header. | |
414 | */ | |
415 | private byte[] recvPayload(SessiondCommandHeader headerCmd) throws IOException { | |
416 | byte payload[] = new byte[(int) headerCmd.getDataSize()]; | |
32974710 MD |
417 | int bytesLeft = payload.length; |
418 | int bytesOffset = 0; | |
f1fa0535 | 419 | |
301a3ddb | 420 | /* Failsafe check so we don't waste our time reading 0 bytes. */ |
32974710 | 421 | if (bytesLeft == 0) { |
301a3ddb | 422 | return null; |
f1fa0535 DG |
423 | } |
424 | ||
dcd9a9d7 | 425 | while (bytesLeft > 0) { |
32974710 MD |
426 | int bytesRead = inFromSessiond.read(payload, bytesOffset, bytesLeft); |
427 | ||
428 | if (bytesRead < 0) { | |
429 | throw new IOException(); | |
430 | } | |
431 | bytesLeft -= bytesRead; | |
432 | bytesOffset += bytesRead; | |
1e111005 | 433 | } |
301a3ddb | 434 | return payload; |
43e5396b DG |
435 | } |
436 | ||
6e1fdc3a AM |
437 | /** |
438 | * Wrapper for this class's logging, adds the connection's characteristics | |
439 | * to help differentiate between multiple TCP clients. | |
440 | */ | |
441 | private void log(String message) { | |
442 | LttngUstAgentLogger.log(getClass(), | |
443 | "(root=" + isRoot + ", domain=" + domainValue + ") " + message); | |
444 | } | |
43e5396b | 445 | } |