org.eclipse.linuxtools.lttng2.kernel.core/src/org/eclipse/linuxtools/lttng2/kernel/core/trace/CtfKernelTrace.java

   1 /*******************************************************************************
   2  * Copyright (c) 2012 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Alexandre Montplaisir - Initial API and implementation
  11  ******************************************************************************/
  12
  13 package org.eclipse.linuxtools.lttng2.kernel.core.trace;
  14
  15 import java.io.File;
  16 import java.io.IOException;
  17
  18 import org.eclipse.core.resources.IProject;
  19 import org.eclipse.core.resources.IResource;
  20 import org.eclipse.core.runtime.CoreException;
  21 import org.eclipse.linuxtools.internal.lttng2.kernel.core.stateprovider.CtfKernelStateInput;
  22 import org.eclipse.linuxtools.tmf.core.TmfCommonConstants;
  23 import org.eclipse.linuxtools.tmf.core.ctfadaptor.CtfTmfTrace;
  24 import org.eclipse.linuxtools.tmf.core.exceptions.TmfTraceException;
  25 import org.eclipse.linuxtools.tmf.core.statesystem.HistoryBuilder;
  26 import org.eclipse.linuxtools.tmf.core.statesystem.IStateChangeInput;
  27 import org.eclipse.linuxtools.tmf.core.statesystem.IStateHistoryBackend;
  28 import org.eclipse.linuxtools.tmf.core.statesystem.backend.historytree.HistoryTreeBackend;
  29 import org.eclipse.linuxtools.tmf.core.statesystem.backend.historytree.ThreadedHistoryTreeBackend;
  30
  31 /**
  32  * This is the specification of CtfTmfTrace for use with LTTng 2.x kernel
  33  * traces. It uses the CtfKernelStateInput to generate the state history.
  34  *
  35  * @author alexmont
  36  *
  37  */
  38 public class CtfKernelTrace extends CtfTmfTrace {
  39
  40     /**
  41      * The file name of the History Tree
  42      */
  43     public final static String HISTORY_TREE_FILE_NAME = "stateHistory.ht"; //$NON-NLS-1$
  44
  45     /** Size of the blocking queue to use when building a state history */
  46     private final static int QUEUE_SIZE = 10000;
  47
  48     public CtfKernelTrace() {
  49         super();
  50     }
  51
  52     @Override
  53     public boolean validate(final IProject project, final String path) {
  54         if (!super.validate(project, path)) {
  55             return false;
  56         }
  57         /* Add extra checks specific to kernel traces here */
  58         return true;
  59     }
  60
  61     @Override
  62     protected void buildStateSystem() throws TmfTraceException {
  63         /* Set up the path to the history tree file we'll use */
  64         IResource resource = getResource();
  65         String supplDirectory = null;
  66
  67         try {
  68             // get the directory where the history file will be stored.
  69             supplDirectory = resource.getPersistentProperty(TmfCommonConstants.TRACE_SUPPLEMENTARY_FOLDER);
  70         } catch (CoreException e) {
  71             throw new TmfTraceException(e.toString(), e);
  72         }
  73
  74         final File htFile = new File(supplDirectory + File.separator + HISTORY_TREE_FILE_NAME);
  75
  76         IStateHistoryBackend htBackend;
  77         IStateChangeInput htInput;
  78         HistoryBuilder builder;
  79
  80         /* If the target file already exists, do not rebuild it uselessly */
  81         // TODO for now we assume it's complete. Might be a good idea to check
  82         // at least if its range matches the trace's range.
  83         if (htFile.exists()) {
  84             /* Load an existing history */
  85             try {
  86                 htBackend = new HistoryTreeBackend(htFile);
  87                 this.ss = HistoryBuilder.openExistingHistory(htBackend);
  88                 return;
  89             } catch (IOException e) {
  90                 /*
  91                  * There was an error opening the existing file. Perhaps it was
  92                  * corrupted, perhaps it's an old version? We'll just
  93                  * fall-through and try to build a new one from scratch instead.
  94                  */
  95             }
  96         }
  97
  98         /* Create a new state history from scratch */
  99         htInput = new CtfKernelStateInput(this);
 100
 101         try {
 102             htBackend = new ThreadedHistoryTreeBackend(htFile,
 103                     htInput.getStartTime(), QUEUE_SIZE);
 104             builder = new HistoryBuilder(htInput, htBackend);
 105         } catch (IOException e) {
 106             /*
 107              * If it fails here however, it means there was a problem writing
 108              * to the disk, so throw a real exception this time.
 109              */
 110             throw new TmfTraceException(e.toString(), e);
 111         }
 112
 113         this.ss = builder.getStateSystemQuerier();
 114     }
 115 }