Commit | Line | Data |
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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 | ||
3287f48b KS |
211 | private String getUstAppPath() { |
212 | String ustAppPath = System.getenv("LTTNG_UST_APP_PATH"); | |
213 | if (ustAppPath != null) { | |
214 | String[] paths = ustAppPath.split(":"); | |
215 | if (paths.length > 1) { | |
216 | log("':' separator in LTTNG_UST_APP_PATH, only the first path will be used"); | |
217 | } | |
218 | return paths[0]; | |
219 | } | |
220 | return ustAppPath; | |
c0f6fb05 MD |
221 | } |
222 | ||
301a3ddb | 223 | private static String getHomePath() { |
59e3be47 MD |
224 | /* |
225 | * The environment variable LTTNG_HOME overrides HOME if | |
c0f6fb05 | 226 | * set. |
59e3be47 | 227 | */ |
c0f6fb05 MD |
228 | String lttngHomePath = System.getenv("LTTNG_HOME"); |
229 | if (lttngHomePath != null) { | |
230 | return lttngHomePath; | |
59e3be47 | 231 | } |
c0f6fb05 | 232 | return System.getProperty("user.home"); |
43e5396b DG |
233 | } |
234 | ||
d60dfbe4 | 235 | /** |
301a3ddb | 236 | * Read port number from file created by the session daemon. |
43e5396b | 237 | * |
301a3ddb | 238 | * @return port value if found else 0. |
43e5396b | 239 | */ |
301a3ddb | 240 | private static int getPortFromFile(String path) throws IOException { |
301a3ddb | 241 | BufferedReader br = null; |
43e5396b | 242 | |
301a3ddb | 243 | try { |
9f84d546 | 244 | br = new BufferedReader(new InputStreamReader(new FileInputStream(path), PORT_FILE_ENCODING)); |
301a3ddb | 245 | String line = br.readLine(); |
8d8c99c9 AM |
246 | if (line == null) { |
247 | /* File exists but is empty. */ | |
248 | return 0; | |
249 | } | |
250 | ||
251 | int port = Integer.parseInt(line, 10); | |
301a3ddb AM |
252 | if (port < 0 || port > 65535) { |
253 | /* Invalid value. Ignore. */ | |
254 | port = 0; | |
255 | } | |
8d8c99c9 AM |
256 | return port; |
257 | ||
258 | } catch (NumberFormatException e) { | |
259 | /* File contained something that was not a number. */ | |
260 | return 0; | |
301a3ddb AM |
261 | } catch (FileNotFoundException e) { |
262 | /* No port available. */ | |
8d8c99c9 | 263 | return 0; |
301a3ddb AM |
264 | } finally { |
265 | if (br != null) { | |
266 | br.close(); | |
267 | } | |
43e5396b | 268 | } |
301a3ddb AM |
269 | } |
270 | ||
271 | private void registerToSessiond() throws IOException { | |
272 | byte data[] = new byte[16]; | |
273 | ByteBuffer buf = ByteBuffer.wrap(data); | |
274 | String pid = ManagementFactory.getRuntimeMXBean().getName().split("@")[0]; | |
275 | ||
3165c2f5 | 276 | buf.putInt(domainValue); |
301a3ddb | 277 | buf.putInt(Integer.parseInt(pid)); |
191f4058 AM |
278 | buf.putInt(PROTOCOL_MAJOR_VERSION); |
279 | buf.putInt(PROTOCOL_MINOR_VERSION); | |
301a3ddb AM |
280 | this.outToSessiond.write(data, 0, data.length); |
281 | this.outToSessiond.flush(); | |
43e5396b DG |
282 | } |
283 | ||
d60dfbe4 | 284 | /** |
43e5396b DG |
285 | * Handle session command from the session daemon. |
286 | */ | |
d60dfbe4 | 287 | private void handleSessiondCmd() throws IOException { |
301a3ddb AM |
288 | /* Data read from the socket */ |
289 | byte inputData[] = null; | |
290 | /* Reply data written to the socket, sent to the sessiond */ | |
f35c6aa0 | 291 | LttngAgentResponse response; |
43e5396b DG |
292 | |
293 | while (true) { | |
294 | /* Get header from session daemon. */ | |
301a3ddb | 295 | SessiondCommandHeader cmdHeader = recvHeader(); |
43e5396b | 296 | |
301a3ddb AM |
297 | if (cmdHeader.getDataSize() > 0) { |
298 | inputData = recvPayload(cmdHeader); | |
43e5396b DG |
299 | } |
300 | ||
301a3ddb | 301 | switch (cmdHeader.getCommandType()) { |
d60dfbe4 AM |
302 | case CMD_REG_DONE: |
303 | { | |
304 | /* | |
305 | * Countdown the registration latch, meaning registration is | |
306 | * done and we can proceed to continue tracing. | |
307 | */ | |
308 | registrationLatch.countDown(); | |
309 | /* | |
310 | * We don't send any reply to the registration done command. | |
311 | * This just marks the end of the initial session setup. | |
312 | */ | |
6e1fdc3a | 313 | log("Registration done"); |
d60dfbe4 AM |
314 | continue; |
315 | } | |
316 | case CMD_LIST: | |
317 | { | |
1d193914 | 318 | SessiondCommand listLoggerCmd = new SessiondListLoggersCommand(); |
f35c6aa0 | 319 | response = listLoggerCmd.execute(logAgent); |
6e1fdc3a | 320 | log("Received list loggers command"); |
d60dfbe4 AM |
321 | break; |
322 | } | |
8ab5c06b | 323 | case CMD_EVENT_ENABLE: |
d60dfbe4 | 324 | { |
301a3ddb AM |
325 | if (inputData == null) { |
326 | /* Invalid command */ | |
f35c6aa0 | 327 | response = LttngAgentResponse.FAILURE_RESPONSE; |
43e5396b DG |
328 | break; |
329 | } | |
8ab5c06b | 330 | SessiondCommand enableEventCmd = new SessiondEnableEventCommand(inputData); |
f35c6aa0 AM |
331 | response = enableEventCmd.execute(logAgent); |
332 | log("Received enable event command: " + enableEventCmd.toString()); | |
d60dfbe4 AM |
333 | break; |
334 | } | |
8ab5c06b | 335 | case CMD_EVENT_DISABLE: |
d60dfbe4 | 336 | { |
301a3ddb AM |
337 | if (inputData == null) { |
338 | /* Invalid command */ | |
f35c6aa0 | 339 | response = LttngAgentResponse.FAILURE_RESPONSE; |
43e5396b DG |
340 | break; |
341 | } | |
8ab5c06b | 342 | SessiondCommand disableEventCmd = new SessiondDisableEventCommand(inputData); |
f35c6aa0 AM |
343 | response = disableEventCmd.execute(logAgent); |
344 | log("Received disable event command: " + disableEventCmd.toString()); | |
8ab5c06b AM |
345 | break; |
346 | } | |
347 | case CMD_APP_CTX_ENABLE: | |
348 | { | |
349 | if (inputData == null) { | |
350 | /* This commands expects a payload, invalid command */ | |
f35c6aa0 | 351 | response = LttngAgentResponse.FAILURE_RESPONSE; |
8ab5c06b AM |
352 | break; |
353 | } | |
354 | SessiondCommand enableAppCtxCmd = new SessiondEnableAppContextCommand(inputData); | |
f35c6aa0 | 355 | response = enableAppCtxCmd.execute(logAgent); |
6e1fdc3a | 356 | log("Received enable app-context command"); |
8ab5c06b AM |
357 | break; |
358 | } | |
359 | case CMD_APP_CTX_DISABLE: | |
360 | { | |
361 | if (inputData == null) { | |
362 | /* This commands expects a payload, invalid command */ | |
f35c6aa0 | 363 | response = LttngAgentResponse.FAILURE_RESPONSE; |
8ab5c06b AM |
364 | break; |
365 | } | |
366 | SessiondCommand disableAppCtxCmd = new SessiondDisableAppContextCommand(inputData); | |
f35c6aa0 | 367 | response = disableAppCtxCmd.execute(logAgent); |
6e1fdc3a | 368 | log("Received disable app-context command"); |
d60dfbe4 AM |
369 | break; |
370 | } | |
371 | default: | |
372 | { | |
301a3ddb | 373 | /* Unknown command, send empty reply */ |
f35c6aa0 | 374 | response = null; |
6e1fdc3a | 375 | log("Received unknown command, ignoring"); |
d60dfbe4 AM |
376 | break; |
377 | } | |
43e5396b DG |
378 | } |
379 | ||
301a3ddb | 380 | /* Send response to the session daemon. */ |
f35c6aa0 AM |
381 | byte[] responseData; |
382 | if (response == null) { | |
383 | responseData = new byte[4]; | |
384 | ByteBuffer buf = ByteBuffer.wrap(responseData); | |
385 | buf.order(ByteOrder.BIG_ENDIAN); | |
386 | } else { | |
387 | log("Sending response: " + response.toString()); | |
388 | responseData = response.getBytes(); | |
389 | } | |
301a3ddb | 390 | this.outToSessiond.write(responseData, 0, responseData.length); |
43e5396b DG |
391 | this.outToSessiond.flush(); |
392 | } | |
393 | } | |
394 | ||
f1fa0535 | 395 | /** |
301a3ddb AM |
396 | * Receive header data from the session daemon using the LTTng command |
397 | * static buffer of the right size. | |
f1fa0535 | 398 | */ |
301a3ddb AM |
399 | private SessiondCommandHeader recvHeader() throws IOException { |
400 | byte data[] = new byte[SessiondCommandHeader.HEADER_SIZE]; | |
32974710 MD |
401 | int bytesLeft = data.length; |
402 | int bytesOffset = 0; | |
f1fa0535 | 403 | |
dcd9a9d7 | 404 | while (bytesLeft > 0) { |
32974710 MD |
405 | int bytesRead = this.inFromSessiond.read(data, bytesOffset, bytesLeft); |
406 | ||
407 | if (bytesRead < 0) { | |
408 | throw new IOException(); | |
409 | } | |
410 | bytesLeft -= bytesRead; | |
411 | bytesOffset += bytesRead; | |
f1fa0535 | 412 | } |
301a3ddb | 413 | return new SessiondCommandHeader(data); |
f1fa0535 DG |
414 | } |
415 | ||
301a3ddb AM |
416 | /** |
417 | * Receive payload from the session daemon. This MUST be done after a | |
418 | * recvHeader() so the header value of a command are known. | |
419 | * | |
420 | * The caller SHOULD use isPayload() before which returns true if a payload | |
421 | * is expected after the header. | |
422 | */ | |
423 | private byte[] recvPayload(SessiondCommandHeader headerCmd) throws IOException { | |
424 | byte payload[] = new byte[(int) headerCmd.getDataSize()]; | |
32974710 MD |
425 | int bytesLeft = payload.length; |
426 | int bytesOffset = 0; | |
f1fa0535 | 427 | |
301a3ddb | 428 | /* Failsafe check so we don't waste our time reading 0 bytes. */ |
32974710 | 429 | if (bytesLeft == 0) { |
301a3ddb | 430 | return null; |
f1fa0535 DG |
431 | } |
432 | ||
dcd9a9d7 | 433 | while (bytesLeft > 0) { |
32974710 MD |
434 | int bytesRead = inFromSessiond.read(payload, bytesOffset, bytesLeft); |
435 | ||
436 | if (bytesRead < 0) { | |
437 | throw new IOException(); | |
438 | } | |
439 | bytesLeft -= bytesRead; | |
440 | bytesOffset += bytesRead; | |
1e111005 | 441 | } |
301a3ddb | 442 | return payload; |
43e5396b DG |
443 | } |
444 | ||
6e1fdc3a AM |
445 | /** |
446 | * Wrapper for this class's logging, adds the connection's characteristics | |
447 | * to help differentiate between multiple TCP clients. | |
448 | */ | |
449 | private void log(String message) { | |
450 | LttngUstAgentLogger.log(getClass(), | |
451 | "(root=" + isRoot + ", domain=" + domainValue + ") " + message); | |
452 | } | |
43e5396b | 453 | } |