org.eclipse.tracecompass.tmf.ctf.core/src/org/eclipse/tracecompass/internal/tmf/ctf/core/trace/iterator/CtfIterator.java

   1 /*******************************************************************************
   2  * Copyright (c) 2012, 2014 Ericsson, École Polytechnique de Montréal
   3  *
   4  * All rights reserved. This program and the accompanying materials are made
   5  * 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  *   Matthew Khouzam - Initial API and implementation
  11  *   Florian Wininger - Performance improvements
  12  *******************************************************************************/
  13
  14 package org.eclipse.tracecompass.internal.tmf.ctf.core.trace.iterator;
  15
  16 import static org.eclipse.tracecompass.common.core.NonNullUtils.equalsNullable;
  17
  18 import org.eclipse.tracecompass.ctf.core.CTFReaderException;
  19 import org.eclipse.tracecompass.ctf.core.trace.CTFStreamInputReader;
  20 import org.eclipse.tracecompass.ctf.core.trace.CTFTrace;
  21 import org.eclipse.tracecompass.ctf.core.trace.CTFTraceReader;
  22 import org.eclipse.tracecompass.internal.tmf.ctf.core.Activator;
  23 import org.eclipse.tracecompass.tmf.core.trace.ITmfContext;
  24 import org.eclipse.tracecompass.tmf.core.trace.location.ITmfLocation;
  25 import org.eclipse.tracecompass.tmf.ctf.core.context.CtfLocation;
  26 import org.eclipse.tracecompass.tmf.ctf.core.context.CtfLocationInfo;
  27 import org.eclipse.tracecompass.tmf.ctf.core.event.CtfTmfEvent;
  28 import org.eclipse.tracecompass.tmf.ctf.core.event.CtfTmfEventFactory;
  29 import org.eclipse.tracecompass.tmf.ctf.core.trace.CtfTmfTrace;
  30
  31 /**
  32  * The CTF trace reader iterator.
  33  *
  34  * It doesn't reserve a file handle, so many iterators can be used without
  35  * worries of I/O errors or resource exhaustion.
  36  *
  37  * @author Matthew Khouzam
  38  */
  39 public class CtfIterator extends CTFTraceReader
  40         implements ITmfContext, Comparable<CtfIterator> {
  41
  42     /** An invalid location */
  43     public static final CtfLocation NULL_LOCATION = new CtfLocation(CtfLocation.INVALID_LOCATION);
  44
  45     private final CtfTmfTrace fTrace;
  46
  47     private CtfLocation fCurLocation;
  48     private long fCurRank;
  49
  50     private CtfLocation fPreviousLocation;
  51     private CtfTmfEvent fPreviousEvent;
  52
  53     // ------------------------------------------------------------------------
  54     // Constructors
  55     // ------------------------------------------------------------------------
  56
  57     /**
  58      * Create a new CTF trace iterator, which initially points at the first
  59      * event in the trace.
  60      *
  61      * @param ctfTrace
  62      *            The {@link CTFTrace} linked to the trace. It should be
  63      *            provided by the corresponding 'ctfTmfTrace'.
  64      *
  65      * @param ctfTmfTrace
  66      *            The {@link CtfTmfTrace} to iterate over
  67      * @throws CTFReaderException
  68      *             If the iterator couldn't not be instantiated, probably due to
  69      *             a read error.
  70      */
  71     public CtfIterator(CTFTrace ctfTrace, CtfTmfTrace ctfTmfTrace) throws CTFReaderException {
  72         super(ctfTrace);
  73         fTrace = ctfTmfTrace;
  74         if (hasMoreEvents()) {
  75             fCurLocation = new CtfLocation(ctfTmfTrace.getStartTime());
  76             fCurRank = 0;
  77         } else {
  78             setUnknownLocation();
  79         }
  80     }
  81
  82     /**
  83      * Create a new CTF trace iterator, which will initially point to the given
  84      * location/rank.
  85      *
  86      * @param ctfTrace
  87      *            The {@link CTFTrace} linked to the trace. It should be
  88      *            provided by the corresponding 'ctfTmfTrace'.
  89      * @param ctfTmfTrace
  90      *            The {@link CtfTmfTrace} to iterate over
  91      * @param ctfLocationData
  92      *            The initial timestamp the iterator will be pointing to
  93      * @param rank
  94      *            The initial rank
  95      * @throws CTFReaderException
  96      *             If the iterator couldn't not be instantiated, probably due to
  97      *             a read error.
  98      */
  99     public CtfIterator(CTFTrace ctfTrace, CtfTmfTrace ctfTmfTrace, CtfLocationInfo ctfLocationData, long rank)
 100             throws CTFReaderException {
 101         super(ctfTrace);
 102
 103         this.fTrace = ctfTmfTrace;
 104         if (this.hasMoreEvents()) {
 105             this.fCurLocation = new CtfLocation(ctfLocationData);
 106             if (this.getCurrentEvent().getTimestamp().getValue() != ctfLocationData.getTimestamp()) {
 107                 this.seek(ctfLocationData);
 108                 this.fCurRank = rank;
 109             }
 110         } else {
 111             setUnknownLocation();
 112         }
 113     }
 114
 115     @Override
 116     public void dispose() {
 117         close();
 118     }
 119
 120     private void setUnknownLocation() {
 121         fCurLocation = NULL_LOCATION;
 122         fCurRank = UNKNOWN_RANK;
 123     }
 124
 125     // ------------------------------------------------------------------------
 126     // Accessors
 127     // ------------------------------------------------------------------------
 128
 129     /**
 130      * Return this iterator's trace.
 131      *
 132      * @return CtfTmfTrace The iterator's trace
 133      */
 134     public CtfTmfTrace getCtfTmfTrace() {
 135         return fTrace;
 136     }
 137
 138     /**
 139      * Return the current event pointed to by the iterator.
 140      *
 141      * @return CtfTmfEvent The current event
 142      */
 143     public synchronized CtfTmfEvent getCurrentEvent() {
 144         final CTFStreamInputReader top = super.getPrio().peek();
 145         if (top != null) {
 146             if (!fCurLocation.equals(fPreviousLocation)) {
 147                 fPreviousLocation = fCurLocation;
 148                 fPreviousEvent = CtfTmfEventFactory.createEvent(top.getCurrentEvent(),
 149                         top.getFilename(), fTrace);
 150             }
 151             return fPreviousEvent;
 152         }
 153         return null;
 154     }
 155
 156     /**
 157      * Return the current timestamp location pointed to by the iterator. This is
 158      * the timestamp for use in CtfLocation, not the event timestamp.
 159      *
 160      * @return long The current timestamp location
 161      */
 162     public synchronized long getCurrentTimestamp() {
 163         final CTFStreamInputReader top = super.getPrio().peek();
 164         if (top != null) {
 165             long ts = top.getCurrentEvent().getTimestamp();
 166             return fTrace.timestampCyclesToNanos(ts);
 167         }
 168         return 0;
 169     }
 170
 171     /**
 172      * Seek this iterator to a given location.
 173      *
 174      * @param ctfLocationData
 175      *            The LocationData representing the position to seek to
 176      * @return boolean True if the seek was successful, false if there was an
 177      *         error seeking.
 178      */
 179     public synchronized boolean seek(CtfLocationInfo ctfLocationData) {
 180         boolean ret = false;
 181
 182         /* Avoid the cost of seeking at the current location. */
 183         if (fCurLocation.getLocationInfo().equals(ctfLocationData)) {
 184             return super.hasMoreEvents();
 185         }
 186
 187         /* Adjust the timestamp depending on the trace's offset */
 188         long currTimestamp = ctfLocationData.getTimestamp();
 189         final long offsetTimestamp = this.getCtfTmfTrace().timestampNanoToCycles(currTimestamp);
 190         try {
 191             if (offsetTimestamp < 0) {
 192                 ret = super.seek(0L);
 193             } else {
 194                 ret = super.seek(offsetTimestamp);
 195             }
 196         } catch (CTFReaderException e) {
 197             Activator.getDefault().logError(e.getMessage(), e);
 198             return false;
 199         }
 200         /*
 201          * Check if there is already one or more events for that timestamp, and
 202          * assign the location index correctly
 203          */
 204         long index = 0;
 205         final CtfTmfEvent currentEvent = this.getCurrentEvent();
 206         if (currentEvent != null) {
 207             currTimestamp = currentEvent.getTimestamp().getValue();
 208
 209             for (long i = 0; i < ctfLocationData.getIndex(); i++) {
 210                 if (currTimestamp == currentEvent.getTimestamp().getValue()) {
 211                     index++;
 212                 } else {
 213                     index = 0;
 214                 }
 215                 this.advance();
 216             }
 217         } else {
 218             ret = false;
 219         }
 220         /* Seek the current location accordingly */
 221         if (ret) {
 222             fCurLocation = new CtfLocation(new CtfLocationInfo(getCurrentEvent().getTimestamp().getValue(), index));
 223         } else {
 224             fCurLocation = NULL_LOCATION;
 225         }
 226
 227         return ret;
 228     }
 229
 230     // ------------------------------------------------------------------------
 231     // CTFTraceReader
 232     // ------------------------------------------------------------------------
 233
 234     @Override
 235     public boolean seek(long timestamp) {
 236         return seek(new CtfLocationInfo(timestamp, 0));
 237     }
 238
 239     @Override
 240     public synchronized boolean advance() {
 241         boolean ret = false;
 242         try {
 243             ret = super.advance();
 244         } catch (CTFReaderException e) {
 245             Activator.getDefault().logError(e.getMessage(), e);
 246         }
 247
 248         if (ret) {
 249             long timestamp = fCurLocation.getLocationInfo().getTimestamp();
 250             final long timestampValue = getCurrentTimestamp();
 251             if (timestamp == timestampValue) {
 252                 long index = fCurLocation.getLocationInfo().getIndex();
 253                 fCurLocation = new CtfLocation(timestampValue, index + 1);
 254             } else {
 255                 fCurLocation = new CtfLocation(timestampValue, 0L);
 256             }
 257         } else {
 258             fCurLocation = NULL_LOCATION;
 259         }
 260         return ret;
 261     }
 262
 263     // ------------------------------------------------------------------------
 264     // ITmfContext
 265     // ------------------------------------------------------------------------
 266
 267     @Override
 268     public long getRank() {
 269         return fCurRank;
 270     }
 271
 272     @Override
 273     public void setRank(long rank) {
 274         fCurRank = rank;
 275     }
 276
 277     @Override
 278     public void increaseRank() {
 279         /* Only increase the rank if it's valid */
 280         if (hasValidRank()) {
 281             fCurRank++;
 282         }
 283     }
 284
 285     @Override
 286     public boolean hasValidRank() {
 287         return (getRank() >= 0);
 288     }
 289
 290     @Override
 291     public void setLocation(ITmfLocation location) {
 292         // FIXME alex: isn't there a cleaner way than a cast here?
 293         fCurLocation = (CtfLocation) location;
 294         seek(((CtfLocation) location).getLocationInfo());
 295     }
 296
 297     @Override
 298     public CtfLocation getLocation() {
 299         return fCurLocation;
 300     }
 301
 302     // ------------------------------------------------------------------------
 303     // Comparable
 304     // ------------------------------------------------------------------------
 305
 306     @Override
 307     public int compareTo(final CtfIterator o) {
 308         if (getRank() < o.getRank()) {
 309             return -1;
 310         } else if (getRank() > o.getRank()) {
 311             return 1;
 312         }
 313         return 0;
 314     }
 315
 316     // ------------------------------------------------------------------------
 317     // Object
 318     // ------------------------------------------------------------------------
 319
 320     @Override
 321     public int hashCode() {
 322         final int prime = 31;
 323         int result = super.hashCode();
 324         result = (prime * result)
 325                 + ((fTrace == null) ? 0 : fTrace.hashCode());
 326         result = (prime * result)
 327                 + ((fCurLocation == null) ? 0 : fCurLocation.hashCode());
 328         result = (prime * result) + (int) (fCurRank ^ (fCurRank >>> 32));
 329         return result;
 330     }
 331
 332     @Override
 333     public boolean equals(Object obj) {
 334         if (this == obj) {
 335             return true;
 336         }
 337         if (!super.equals(obj)) {
 338             return false;
 339         }
 340         if (!(obj instanceof CtfIterator)) {
 341             return false;
 342         }
 343         CtfIterator other = (CtfIterator) obj;
 344         if (!equalsNullable(fTrace, other.fTrace)) {
 345             return false;
 346         }
 347         if (!equalsNullable(fCurLocation, other.fCurLocation)) {
 348             return false;
 349         }
 350         if (fCurRank != other.fCurRank) {
 351             return false;
 352         }
 353         return true;
 354     }
 355 }