liblttng-ust-java-agent/java/lttng-ust-agent-common/org/lttng/ust/agent/client/SessiondEnableEventCommand.java

   1 /*
   2  * Copyright (C) 2015 - EfficiOS Inc., Alexandre Montplaisir <alexmonthy@efficios.com>
   3  * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com>
   4  *
   5  * This library is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU Lesser General Public License, version 2.1 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This library is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
  12  * for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public License
  15  * along with this library; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 package org.lttng.ust.agent.client;
  20
  21 import java.nio.ByteBuffer;
  22 import java.nio.ByteOrder;
  23
  24 import org.lttng.ust.agent.session.EventRule;
  25 import org.lttng.ust.agent.session.LogLevelSelector;
  26
  27 /**
  28  * Session daemon command indicating to the Java agent that some events were
  29  * enabled in the tracing session.
  30  *
  31  * @author Alexandre Montplaisir
  32  * @author David Goulet
  33  */
  34 class SessiondEnableEventCommand implements ISessiondCommand {
  35
  36         private static final int INT_SIZE = 4;
  37
  38         /* Parameters of the event rule being enabled */
  39         private final String eventName;
  40         private final LogLevelSelector logLevelFilter;
  41         private final String filterString;
  42
  43         public SessiondEnableEventCommand(byte[] data) {
  44                 if (data == null) {
  45                         throw new IllegalArgumentException();
  46                 }
  47                 int dataOffset = INT_SIZE * 2;
  48
  49                 ByteBuffer buf = ByteBuffer.wrap(data);
  50                 buf.order(ByteOrder.LITTLE_ENDIAN);
  51                 int logLevel = buf.getInt();
  52                 int logLevelType = buf.getInt();
  53                 logLevelFilter = new LogLevelSelector(logLevel, logLevelType);
  54
  55                 eventName = new String(data, dataOffset, data.length - dataOffset).trim();
  56                 filterString = null; /* Not yet sent by the sessiond */
  57         }
  58
  59         @Override
  60         public LttngAgentResponse execute(ILttngTcpClientListener agent) {
  61                 EventRule rule = new EventRule(eventName, logLevelFilter, filterString);
  62                 boolean success = agent.eventEnabled(rule);
  63                 return (success ? LttngAgentResponse.SUCESS_RESPONSE : LttngAgentResponse.FAILURE_RESPONSE);
  64         }
  65 }