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

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2015 EfficiOS Inc.
   5  * Copyright (C) 2015 Alexandre Montplaisir <alexmonthy@efficios.com>
   6  * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
   7  */
   8
   9 package org.lttng.ust.agent.client;
  10
  11 import java.nio.ByteBuffer;
  12 import java.nio.ByteOrder;
  13
  14 import org.lttng.ust.agent.client.SessiondCommand.CommandType;
  15
  16 /**
  17  * Header of session daemon commands.
  18  *
  19  * @author Alexandre Montplaisir
  20  * @author David Goulet
  21  */
  22 class SessiondCommandHeader {
  23
  24         /** ABI size of command header. */
  25         public static final int HEADER_SIZE = 16;
  26
  27         /** Payload size in bytes following this header. */
  28         private final long dataSize;
  29
  30         /** Command type. */
  31         private final CommandType cmd;
  32
  33         public SessiondCommandHeader(byte[] data) {
  34                 ByteBuffer buf = ByteBuffer.wrap(data);
  35                 buf.order(ByteOrder.BIG_ENDIAN);
  36
  37                 dataSize = buf.getLong();
  38                 cmd = CommandType.values()[buf.getInt() - 1];
  39                 buf.getInt(); // command version, currently unused
  40         }
  41
  42         public long getDataSize() {
  43                 return dataSize;
  44         }
  45
  46         public CommandType getCommandType() {
  47                 return cmd;
  48         }
  49 }