liblttng-ust-jul/org/lttng/ust/jul/LTTngTCPSessiondClient.java

   1 /*
   2  * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com>
   3  *
   4  * This library is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU Lesser General Public License, version 2.1 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This library is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
  11  * for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this library; if not, write to the Free Software Foundation,
  15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  16  */
  17
  18 package org.lttng.ust.jul;
  19
  20 import java.util.concurrent.Semaphore;
  21 import java.nio.ByteBuffer;
  22 import java.nio.ByteOrder;
  23 import java.lang.Integer;
  24 import java.io.IOException;
  25 import java.io.BufferedOutputStream;
  26 import java.io.BufferedReader;
  27 import java.io.ByteArrayOutputStream;
  28 import java.io.DataOutputStream;
  29 import java.io.DataInputStream;
  30 import java.io.FileReader;
  31 import java.io.FileNotFoundException;
  32 import java.net.*;
  33 import java.lang.management.ManagementFactory;
  34 import java.util.ArrayList;
  35 import java.util.HashMap;
  36 import java.util.HashSet;
  37 import java.util.Iterator;
  38 import java.util.List;
  39 import java.util.Set;
  40 import java.util.Timer;
  41 import java.util.TimerTask;
  42 import java.util.logging.Logger;
  43 import java.util.Collections;
  44
  45 class USTRegisterMsg {
  46         public static int pid;
  47 }
  48
  49 public class LTTngTCPSessiondClient {
  50         /* Command header from the session deamon. */
  51         private LTTngSessiondCmd2_4.sessiond_hdr headerCmd =
  52                 new LTTngSessiondCmd2_4.sessiond_hdr();
  53
  54         private final String sessiondHost;
  55         private Socket sessiondSock;
  56         private boolean quit = false;
  57
  58         private DataInputStream inFromSessiond;
  59         private DataOutputStream outToSessiond;
  60
  61         private LTTngLogHandler handler;
  62
  63         private Semaphore registerSem;
  64
  65         private Timer eventTimer;
  66         private Set<LTTngEvent> enabledEventSet =
  67                 Collections.synchronizedSet(new HashSet<LTTngEvent>());
  68         /*
  69          * Map of Logger objects that have been enabled. They are indexed by name.
  70          */
  71         private HashMap<String, Logger> enabledLoggers = new HashMap<String, Logger>();
  72         /* Timer delay at each 5 seconds. */
  73         private final static long timerDelay = 5 * 1000;
  74         private static boolean timerInitialized;
  75
  76         private static final String rootPortFile = "/var/run/lttng/jul.port";
  77         private static final String userPortFile = "/.lttng/jul.port";
  78
  79         /* Indicate if we've already release the semaphore. */
  80         private boolean sem_posted = false;
  81
  82         public LTTngTCPSessiondClient(String host, Semaphore sem) {
  83                 this.sessiondHost = host;
  84                 this.registerSem = sem;
  85                 this.eventTimer = new Timer();
  86                 this.timerInitialized = false;
  87         }
  88
  89         private void setupEventTimer() {
  90                 if (this.timerInitialized) {
  91                         return;
  92                 }
  93
  94                 this.eventTimer.scheduleAtFixedRate(new TimerTask() {
  95                         @Override
  96                         public void run() {
  97                                 synchronized (enabledEventSet) {
  98                                         LTTngSessiondCmd2_4.sessiond_enable_handler enableCmd = new
  99                                                 LTTngSessiondCmd2_4.sessiond_enable_handler();
 100                                         /*
 101                                          * Modifying events in a Set will raise a
 102                                          * ConcurrentModificationException. Thus, we remove an event
 103                                          * and add its modified version to modifiedEvents when a
 104                                          * modification is necessary.
 105                                          */
 106                                         Set<LTTngEvent> modifiedEvents = new HashSet<LTTngEvent>();
 107                                         Iterator<LTTngEvent> it = enabledEventSet.iterator();
 108
 109                                         while (it.hasNext()) {
 110                                                 int ret;
 111                                                 Logger logger;
 112                                                 LTTngEvent event = it.next();
 113
 114                                                 /*
 115                                                  * Check if this Logger name has been enabled already. Note
 116                                                  * that in the case of "*", it's never added in that hash
 117                                                  * table thus the enable command does a lookup for each
 118                                                  * logger name in that hash table for the * case in order
 119                                                  * to make sure we don't enable twice the same logger
 120                                                  * because JUL apparently accepts that the *same*
 121                                                  * LogHandler can be added twice on a Logger object...
 122                                                  * don't ask...
 123                                                  */
 124                                                 logger = enabledLoggers.get(event.name);
 125                                                 if (logger != null) {
 126                                                         continue;
 127                                                 }
 128
 129                                                 /*
 130                                                  * Set to one means that the enable all event has been seen
 131                                                  * thus event from that point on must use loglevel for all
 132                                                  * events. Else the object has its own loglevel.
 133                                                  */
 134                                                 if (handler.logLevelUseAll == 1) {
 135                                                         it.remove();
 136                                                         event.logLevels.addAll(handler.logLevelsAll);
 137                                                         modifiedEvents.add(event);
 138                                                 }
 139
 140                                                 /*
 141                                                  * The all event is a special case since we have to iterate
 142                                                  * over every Logger to see which one was not enabled.
 143                                                  */
 144                                                 if (event.name.equals("*")) {
 145                                                         enableCmd.name = event.name;
 146                                                         /* Tell the command NOT to add the loglevel. */
 147                                                         enableCmd.lttngLogLevel = -1;
 148                                                         /*
 149                                                          * The return value is irrelevant since the * event is
 150                                                          * always kept in the set.
 151                                                          */
 152                                                         enableCmd.execute(handler, enabledLoggers);
 153                                                         continue;
 154                                                 }
 155
 156                                                 ret = enableCmd.enableLogger(handler, event, enabledLoggers);
 157                                                 if (ret == 1) {
 158                                                         /* Enabled so remove the event from the set. */
 159                                                         if (!modifiedEvents.remove(event)) {
 160                                                                 /*
 161                                                                  * event can only be present in one of
 162                                                                  * the sets.
 163                                                                  */
 164                                                                 it.remove();
 165                                                         }
 166                                                 }
 167                                         }
 168                                         enabledEventSet.addAll(modifiedEvents);
 169                                 }
 170
 171                         }
 172                 }, this.timerDelay, this.timerDelay);
 173
 174                 this.timerInitialized = true;
 175         }
 176
 177         /*
 178          * Try to release the registerSem if it's not already done.
 179          */
 180         private void tryReleaseSem()
 181         {
 182                 /* Release semaphore so we unblock the agent. */
 183                 if (!this.sem_posted) {
 184                         this.registerSem.release();
 185                         this.sem_posted = true;
 186                 }
 187         }
 188
 189         public void init(LTTngLogHandler handler) throws InterruptedException {
 190                 this.handler = handler;
 191
 192                 for (;;) {
 193                         if (this.quit) {
 194                                 break;
 195                         }
 196
 197                         try {
 198
 199                                 /*
 200                                  * Connect to the session daemon before anything else.
 201                                  */
 202                                 connectToSessiond();
 203
 204                                 /*
 205                                  * Register to the session daemon as the Java component of the
 206                                  * UST application.
 207                                  */
 208                                 registerToSessiond();
 209
 210                                 setupEventTimer();
 211
 212                                 /*
 213                                  * Block on socket receive and wait for command from the
 214                                  * session daemon. This will return if and only if there is a
 215                                  * fatal error or the socket closes.
 216                                  */
 217                                 handleSessiondCmd();
 218                         } catch (UnknownHostException uhe) {
 219                                 tryReleaseSem();
 220                                 System.out.println(uhe);
 221                         } catch (IOException ioe) {
 222                                 tryReleaseSem();
 223                                 Thread.sleep(3000);
 224                         } catch (Exception e) {
 225                                 tryReleaseSem();
 226                                 e.printStackTrace();
 227                         }
 228                 }
 229         }
 230
 231         public void destroy() {
 232                 this.quit = true;
 233                 this.eventTimer.cancel();
 234
 235                 try {
 236                         if (this.sessiondSock != null) {
 237                                 this.sessiondSock.close();
 238                         }
 239                 } catch (Exception e) {
 240                         e.printStackTrace();
 241                 }
 242         }
 243
 244         /*
 245          * Receive header data from the session daemon using the LTTng command
 246          * static buffer of the right size.
 247          */
 248         private void recvHeader() throws Exception {
 249                 int read_len;
 250                 byte data[] = new byte[this.headerCmd.SIZE];
 251
 252                 read_len = this.inFromSessiond.read(data, 0, data.length);
 253                 if (read_len != data.length) {
 254                         throw new IOException();
 255                 }
 256                 this.headerCmd.populate(data);
 257         }
 258
 259         /*
 260          * Receive payload from the session daemon. This MUST be done after a
 261          * recvHeader() so the header value of a command are known.
 262          *
 263          * The caller SHOULD use isPayload() before which returns true if a payload
 264          * is expected after the header.
 265          */
 266         private byte[] recvPayload() throws Exception {
 267                 byte payload[] = new byte[(int) this.headerCmd.data_size];
 268
 269                 /* Failsafe check so we don't waste our time reading 0 bytes. */
 270                 if (payload.length == 0) {
 271                         return null;
 272                 }
 273
 274                 this.inFromSessiond.read(payload, 0, payload.length);
 275                 return payload;
 276         }
 277
 278         /*
 279          * Handle session command from the session daemon.
 280          */
 281         private void handleSessiondCmd() throws Exception {
 282                 int ret_code;
 283                 byte data[] = null;
 284
 285                 while (true) {
 286                         /* Get header from session daemon. */
 287                         recvHeader();
 288
 289                         if (headerCmd.data_size > 0) {
 290                                 data = recvPayload();
 291                         }
 292
 293                         switch (headerCmd.cmd) {
 294                                 case CMD_REG_DONE:
 295                                 {
 296                                         /*
 297                                          * Release semaphore so meaning registration is done and we
 298                                          * can proceed to continue tracing.
 299                                          */
 300                                         tryReleaseSem();
 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                                          */
 305                                         continue;
 306                                 }
 307                                 case CMD_LIST:
 308                                 {
 309                                         LTTngSessiondCmd2_4.sessiond_list_logger listLoggerCmd =
 310                                                 new LTTngSessiondCmd2_4.sessiond_list_logger();
 311                                         listLoggerCmd.execute(this.handler);
 312                                         data = listLoggerCmd.getBytes();
 313                                         break;
 314                                 }
 315                                 case CMD_ENABLE:
 316                                 {
 317                                         LTTngEvent event;
 318                                         LTTngSessiondCmd2_4.sessiond_enable_handler enableCmd =
 319                                                 new LTTngSessiondCmd2_4.sessiond_enable_handler();
 320                                         if (data == null) {
 321                                                 enableCmd.code = LTTngSessiondCmd2_4.lttng_jul_ret_code.CODE_INVALID_CMD;
 322                                                 break;
 323                                         }
 324                                         enableCmd.populate(data);
 325                                         event = enableCmd.execute(this.handler, this.enabledLoggers);
 326                                         if (event != null) {
 327                                                 /*
 328                                                  * Add the event to the set so it can be enabled if
 329                                                  * the logger appears at some point in time.
 330                                                  */
 331                                                 enabledEventSet.add(event);
 332                                         }
 333                                         data = enableCmd.getBytes();
 334                                         break;
 335                                 }
 336                                 case CMD_DISABLE:
 337                                 {
 338                                         LTTngSessiondCmd2_4.sessiond_disable_handler disableCmd =
 339                                                 new LTTngSessiondCmd2_4.sessiond_disable_handler();
 340                                         if (data == null) {
 341                                                 disableCmd.code = LTTngSessiondCmd2_4.lttng_jul_ret_code.CODE_INVALID_CMD;
 342                                                 break;
 343                                         }
 344                                         disableCmd.populate(data);
 345                                         disableCmd.execute(this.handler);
 346                                         data = disableCmd.getBytes();
 347                                         break;
 348                                 }
 349                                 default:
 350                                 {
 351                                         data = new byte[4];
 352                                         ByteBuffer buf = ByteBuffer.wrap(data);
 353                                         buf.order(ByteOrder.BIG_ENDIAN);
 354                                         LTTngSessiondCmd2_4.lttng_jul_ret_code code =
 355                                                 LTTngSessiondCmd2_4.lttng_jul_ret_code.CODE_INVALID_CMD;
 356                                         buf.putInt(code.getCode());
 357                                         break;
 358                                 }
 359                         }
 360
 361                         /* Send payload to session daemon. */
 362                         this.outToSessiond.write(data, 0, data.length);
 363                         this.outToSessiond.flush();
 364                 }
 365         }
 366
 367         private String getHomePath() {
 368                 return System.getProperty("user.home");
 369         }
 370
 371         /**
 372          * Read port number from file created by the session daemon.
 373          *
 374          * @return port value if found else 0.
 375          */
 376         private int getPortFromFile(String path) throws IOException {
 377                 int port;
 378                 BufferedReader br;
 379
 380                 try {
 381                         br = new BufferedReader(new FileReader(path));
 382                         String line = br.readLine();
 383                         port = Integer.parseInt(line, 10);
 384                         if (port < 0 || port > 65535) {
 385                                 /* Invalid value. Ignore. */
 386                                 port = 0;
 387                         }
 388                         br.close();
 389                 } catch (FileNotFoundException e) {
 390                         /* No port available. */
 391                         port = 0;
 392                 }
 393
 394                 return port;
 395         }
 396
 397         private void connectToSessiond() throws Exception {
 398                 int port;
 399
 400                 if (this.handler.is_root == 1) {
 401                         port = getPortFromFile(rootPortFile);
 402                         if (port == 0) {
 403                                 /* No session daemon available. Stop and retry later. */
 404                                 throw new IOException();
 405                         }
 406                 } else {
 407                         port = getPortFromFile(getHomePath() + userPortFile);
 408                         if (port == 0) {
 409                                 /* No session daemon available. Stop and retry later. */
 410                                 throw new IOException();
 411                         }
 412                 }
 413
 414                 this.sessiondSock = new Socket(this.sessiondHost, port);
 415                 this.inFromSessiond = new DataInputStream(
 416                                 sessiondSock.getInputStream());
 417                 this.outToSessiond = new DataOutputStream(
 418                                 sessiondSock.getOutputStream());
 419         }
 420
 421         private void registerToSessiond() throws Exception {
 422                 byte data[] = new byte[4];
 423                 ByteBuffer buf = ByteBuffer.wrap(data);
 424                 String pid = ManagementFactory.getRuntimeMXBean().getName().split("@")[0];
 425
 426                 buf.putInt(Integer.parseInt(pid));
 427                 this.outToSessiond.write(data, 0, data.length);
 428                 this.outToSessiond.flush();
 429         }
 430 }