org.eclipse.linuxtools.ctf.core/src/org/eclipse/linuxtools/ctf/core/trace/StreamInputPacketReader.java

   1 /*******************************************************************************
   2  * Copyright (c) 2011-2013 Ericsson, Ecole Polytechnique de Montreal and others
   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: Matthew Khouzam - Initial API and implementation
  10  * Contributors: Simon Marchi - Initial API and implementation
  11  *******************************************************************************/
  12 package org.eclipse.linuxtools.ctf.core.trace;
  13
  14 import java.io.IOException;
  15 import java.nio.MappedByteBuffer;
  16 import java.nio.channels.FileChannel.MapMode;
  17 import java.util.Collection;
  18
  19 import org.eclipse.linuxtools.ctf.core.CTFStrings;
  20 import org.eclipse.linuxtools.ctf.core.event.EventDefinition;
  21 import org.eclipse.linuxtools.ctf.core.event.IEventDeclaration;
  22 import org.eclipse.linuxtools.ctf.core.event.io.BitBuffer;
  23 import org.eclipse.linuxtools.ctf.core.event.types.Definition;
  24 import org.eclipse.linuxtools.ctf.core.event.types.IDefinitionScope;
  25 import org.eclipse.linuxtools.ctf.core.event.types.IntegerDefinition;
  26 import org.eclipse.linuxtools.ctf.core.event.types.SimpleDatatypeDefinition;
  27 import org.eclipse.linuxtools.ctf.core.event.types.StructDeclaration;
  28 import org.eclipse.linuxtools.ctf.core.event.types.StructDefinition;
  29 import org.eclipse.linuxtools.ctf.core.event.types.VariantDefinition;
  30 import org.eclipse.linuxtools.internal.ctf.core.event.EventDeclaration;
  31 import org.eclipse.linuxtools.internal.ctf.core.trace.StreamInputPacketIndexEntry;
  32
  33 /**
  34  * CTF trace packet reader. Reads the events of a packet of a trace file.
  35  *
  36  * @version 1.0
  37  * @author Matthew Khouzam
  38  * @author Simon Marchi
  39  */
  40 public class StreamInputPacketReader implements IDefinitionScope {
  41
  42     // ------------------------------------------------------------------------
  43     // Attributes
  44     // ------------------------------------------------------------------------
  45
  46     /** BitBuffer used to read the trace file. */
  47     private final BitBuffer bitBuffer;
  48
  49     /** StreamInputReader that uses this StreamInputPacketReader. */
  50     private final StreamInputReader streamInputReader;
  51
  52     /** Trace packet header. */
  53     private final StructDefinition tracePacketHeaderDef;
  54
  55     /** Stream packet context definition. */
  56     private final StructDefinition streamPacketContextDef;
  57
  58     /** Stream event header definition. */
  59     private final StructDefinition streamEventHeaderDef;
  60
  61     /** Stream event context definition. */
  62     private final StructDefinition streamEventContextDef;
  63
  64     /** Reference to the index entry of the current packet. */
  65     private StreamInputPacketIndexEntry currentPacket = null;
  66
  67     /**
  68      * Last timestamp recorded.
  69      *
  70      * Needed to calculate the complete timestamp values for the events with
  71      * compact headers.
  72      */
  73     private long lastTimestamp = 0;
  74
  75     /** CPU id of current packet. */
  76     private int currentCpu = 0;
  77
  78     private int lostEventsInThisPacket;
  79
  80     private long lostEventsDuration;
  81
  82     private boolean hasLost = false;
  83
  84     // ------------------------------------------------------------------------
  85     // Constructors
  86     // ------------------------------------------------------------------------
  87
  88     /**
  89      * Constructs a StreamInputPacketReader.
  90      *
  91      * @param streamInputReader
  92      *            The StreamInputReader to which this packet reader belongs to.
  93      */
  94     public StreamInputPacketReader(StreamInputReader streamInputReader) {
  95         this.streamInputReader = streamInputReader;
  96
  97         /* Set the BitBuffer's byte order. */
  98         bitBuffer = new BitBuffer();
  99         bitBuffer.setByteOrder(streamInputReader.getByteOrder());
 100
 101         /* Create trace packet header definition. */
 102         final Stream currentStream = streamInputReader.getStreamInput().getStream();
 103         StructDeclaration tracePacketHeaderDecl = currentStream.getTrace().getPacketHeader();
 104         if (tracePacketHeaderDecl != null) {
 105             tracePacketHeaderDef = tracePacketHeaderDecl.createDefinition(this, "trace.packet.header"); //$NON-NLS-1$
 106         } else {
 107             tracePacketHeaderDef = null;
 108         }
 109
 110         /* Create stream packet context definition. */
 111         StructDeclaration streamPacketContextDecl = currentStream.getPacketContextDecl();
 112         if (streamPacketContextDecl != null) {
 113             streamPacketContextDef = streamPacketContextDecl.createDefinition(this, "stream.packet.context"); //$NON-NLS-1$
 114         } else {
 115             streamPacketContextDef = null;
 116         }
 117
 118         /* Create stream event header definition. */
 119         StructDeclaration streamEventHeaderDecl = currentStream.getEventHeaderDecl();
 120         if (streamEventHeaderDecl != null) {
 121             streamEventHeaderDef = streamEventHeaderDecl.createDefinition(this, "stream.event.header"); //$NON-NLS-1$
 122         } else {
 123             streamEventHeaderDef = null;
 124         }
 125
 126         /* Create stream event context definition. */
 127         StructDeclaration streamEventContextDecl = currentStream.getEventContextDecl();
 128         if (streamEventContextDecl != null) {
 129             streamEventContextDef = streamEventContextDecl.createDefinition(this, "stream.event.context"); //$NON-NLS-1$
 130         } else {
 131             streamEventContextDef = null;
 132         }
 133
 134         /* Create event definitions */
 135         Collection<IEventDeclaration> eventDecls = streamInputReader.getStreamInput().getStream().getEvents().values();
 136
 137         for (IEventDeclaration event : eventDecls) {
 138             if (!streamInputReader.getEventDefinitions().containsKey(event.getId())) {
 139                 EventDefinition eventDef = event.createDefinition(streamInputReader);
 140                 streamInputReader.addEventDefinition(event.getId(), eventDef);
 141             }
 142         }
 143     }
 144
 145     /**
 146      * Dispose the StreamInputPacketReader
 147      *
 148      * @since 2.0
 149      */
 150     public void dispose() {
 151         bitBuffer.setByteBuffer(null);
 152     }
 153
 154     // ------------------------------------------------------------------------
 155     // Getters/Setters/Predicates
 156     // ------------------------------------------------------------------------
 157
 158     /**
 159      * Gets the current packet
 160      *
 161      * @return the current packet
 162      */
 163     StreamInputPacketIndexEntry getCurrentPacket() {
 164         return this.currentPacket;
 165     }
 166
 167     /**
 168      * Gets the steamPacketContext Definition
 169      *
 170      * @return steamPacketContext Definition
 171      */
 172     public StructDefinition getStreamPacketContextDef() {
 173         return this.streamPacketContextDef;
 174     }
 175
 176     /**
 177      * Gets the stream's event context definition.
 178      *
 179      * @return The streamEventContext definition
 180      */
 181     public StructDefinition getStreamEventContextDef() {
 182         return streamEventContextDef;
 183     }
 184
 185     /**
 186      * Gets the CPU (core) number
 187      *
 188      * @return the CPU (core) number
 189      */
 190     public int getCPU() {
 191         return this.currentCpu;
 192     }
 193
 194     @Override
 195     public String getPath() {
 196         return ""; //$NON-NLS-1$
 197     }
 198
 199     // ------------------------------------------------------------------------
 200     // Operations
 201     // ------------------------------------------------------------------------
 202
 203     /**
 204      * Changes the current packet to the given one.
 205      *
 206      * @param currentPacket
 207      *            The index entry of the packet to switch to.
 208      * @throws CTFReaderException
 209      *             If we get an error reading the packet
 210      */
 211     void setCurrentPacket(StreamInputPacketIndexEntry currentPacket) throws CTFReaderException {
 212         StreamInputPacketIndexEntry prevPacket = null;
 213         this.currentPacket = currentPacket;
 214
 215         if (this.currentPacket != null) {
 216             /*
 217              * Change the map of the BitBuffer.
 218              */
 219             MappedByteBuffer bb = null;
 220             try {
 221                 bb = streamInputReader.getStreamInput().getFileChannel()
 222                         .map(MapMode.READ_ONLY,
 223                                 this.currentPacket.getOffsetBytes(),
 224                                 (this.currentPacket.getPacketSizeBits() + 7) / 8);
 225             } catch (IOException e) {
 226                 /*
 227                  * The streamInputReader object is already allocated, so this
 228                  * shouldn't fail bar some very bad kernel or RAM errors...
 229                  */
 230                 e.printStackTrace();
 231             }
 232
 233             bitBuffer.setByteBuffer(bb);
 234
 235             /*
 236              * Read trace packet header.
 237              */
 238             if (tracePacketHeaderDef != null) {
 239                 tracePacketHeaderDef.read(bitBuffer);
 240             }
 241
 242             /*
 243              * Read stream packet context.
 244              */
 245             if (getStreamPacketContextDef() != null) {
 246                 getStreamPacketContextDef().read(bitBuffer);
 247
 248                 /* Read CPU ID */
 249                 if (this.getCurrentPacket().getTarget() != null) {
 250                     this.currentCpu = (int) this.getCurrentPacket().getTargetId();
 251                 }
 252
 253                 /* Read number of lost events */
 254                 lostEventsInThisPacket = (int) this.getCurrentPacket().getLostEvents();
 255                 if (lostEventsInThisPacket != 0) {
 256                     hasLost = true;
 257                     /*
 258                      * Compute the duration of the lost event time range. If the
 259                      * current packet is the first packet, duration will be set
 260                      * to 1.
 261                      */
 262                     long lostEventsStartTime;
 263                     int index = this.streamInputReader.getStreamInput().getIndex().getEntries().indexOf(currentPacket);
 264                     if (index == 0) {
 265                         lostEventsStartTime = currentPacket.getTimestampBegin() + 1;
 266                     } else {
 267                         prevPacket = this.streamInputReader.getStreamInput().getIndex().getEntries().get(index - 1);
 268                         lostEventsStartTime = prevPacket.getTimestampEnd();
 269                     }
 270                     lostEventsDuration = Math.abs(lostEventsStartTime - currentPacket.getTimestampBegin());
 271                 }
 272             }
 273
 274             /*
 275              * Use the timestamp begin of the packet as the reference for the
 276              * timestamp reconstitution.
 277              */
 278             lastTimestamp = currentPacket.getTimestampBegin();
 279         } else {
 280             bitBuffer.setByteBuffer(null);
 281
 282             lastTimestamp = 0;
 283         }
 284     }
 285
 286     /**
 287      * Returns whether it is possible to read any more events from this packet.
 288      *
 289      * @return True if it is possible to read any more events from this packet.
 290      */
 291     public boolean hasMoreEvents() {
 292         if (currentPacket != null) {
 293             return hasLost || (bitBuffer.position() < currentPacket.getContentSizeBits());
 294         }
 295         return false;
 296     }
 297
 298     /**
 299      * Reads the next event of the packet into the right event definition.
 300      *
 301      * @return The event definition containing the event data that was just
 302      *         read.
 303      * @throws CTFReaderException
 304      *             If there was a problem reading the trace
 305      */
 306     public EventDefinition readNextEvent() throws CTFReaderException {
 307         /* Default values for those fields */
 308         long eventID = EventDeclaration.UNSET_EVENT_ID;
 309         long timestamp = 0;
 310         if (hasLost) {
 311             hasLost = false;
 312             EventDefinition eventDef = EventDeclaration.getLostEventDeclaration().createDefinition(streamInputReader);
 313             ((IntegerDefinition) eventDef.getFields().getDefinitions().get(CTFStrings.LOST_EVENTS_FIELD)).setValue(lostEventsInThisPacket);
 314             ((IntegerDefinition) eventDef.getFields().getDefinitions().get(CTFStrings.LOST_EVENTS_DURATION)).setValue(lostEventsDuration);
 315             eventDef.setTimestamp(this.lastTimestamp);
 316             return eventDef;
 317         }
 318
 319         final StructDefinition sehd = streamEventHeaderDef;
 320         final BitBuffer currentBitBuffer = bitBuffer;
 321
 322         /* Read the stream event header. */
 323         if (sehd != null) {
 324             sehd.read(currentBitBuffer);
 325
 326             /* Check for the event id. */
 327             Definition idDef = sehd.lookupDefinition("id"); //$NON-NLS-1$
 328             if (idDef instanceof SimpleDatatypeDefinition) {
 329                 eventID = ((SimpleDatatypeDefinition) idDef).getIntegerValue();
 330             } // else, eventID remains 0
 331
 332             /*
 333              * Get the timestamp from the event header (may be overridden later
 334              * on)
 335              */
 336             IntegerDefinition timestampDef = sehd.lookupInteger("timestamp"); //$NON-NLS-1$
 337             if (timestampDef != null) {
 338                 timestamp = calculateTimestamp(timestampDef);
 339             } // else timestamp remains 0
 340
 341             /* Check for the variant v. */
 342             Definition variantDef = sehd.lookupDefinition("v"); //$NON-NLS-1$
 343             if (variantDef instanceof VariantDefinition) {
 344
 345                 /* Get the variant current field */
 346                 StructDefinition variantCurrentField = (StructDefinition) ((VariantDefinition) variantDef).getCurrentField();
 347
 348                 /*
 349                  * Try to get the id field in the current field of the variant.
 350                  * If it is present, it overrides the previously read event id.
 351                  */
 352                 Definition idIntegerDef = variantCurrentField.lookupDefinition("id"); //$NON-NLS-1$
 353                 if (idIntegerDef instanceof IntegerDefinition) {
 354                     eventID = ((IntegerDefinition) idIntegerDef).getValue();
 355                 }
 356
 357                 /*
 358                  * Get the timestamp. This would overwrite any previous
 359                  * timestamp definition
 360                  */
 361                 Definition def = variantCurrentField.lookupDefinition("timestamp"); //$NON-NLS-1$
 362                 if (def instanceof IntegerDefinition) {
 363                     timestamp = calculateTimestamp((IntegerDefinition) def);
 364                 }
 365             }
 366         }
 367
 368         /* Read the stream event context. */
 369         if (streamEventContextDef != null) {
 370             streamEventContextDef.read(currentBitBuffer);
 371         }
 372
 373         /* Get the right event definition using the event id. */
 374         EventDefinition eventDef = streamInputReader.getEventDefinitions().get(eventID);
 375         if (eventDef == null) {
 376             throw new CTFReaderException("Incorrect event id : " + eventID); //$NON-NLS-1$
 377         }
 378
 379         /* Read the event context. */
 380         if (eventDef.getEventContext() != null) {
 381             eventDef.getEventContext().read(currentBitBuffer);
 382         }
 383
 384         /* Read the event fields. */
 385         if (eventDef.getFields() != null) {
 386             eventDef.getFields().read(currentBitBuffer);
 387         }
 388
 389         /*
 390          * Set the event timestamp using the timestamp calculated by
 391          * updateTimestamp.
 392          */
 393         eventDef.setTimestamp(timestamp);
 394
 395         return eventDef;
 396     }
 397
 398     /**
 399      * Calculates the timestamp value of the event, possibly using the timestamp
 400      * from the last event.
 401      *
 402      * @param timestampDef
 403      *            Integer definition of the timestamp.
 404      * @return The calculated timestamp value.
 405      */
 406     private long calculateTimestamp(IntegerDefinition timestampDef) {
 407         long newval;
 408         long majorasbitmask;
 409         int len = timestampDef.getDeclaration().getLength();
 410
 411         /*
 412          * If the timestamp length is 64 bits, it is a full timestamp.
 413          */
 414         if (timestampDef.getDeclaration().getLength() == 64) {
 415             lastTimestamp = timestampDef.getValue();
 416             return lastTimestamp;
 417         }
 418
 419         /*
 420          * Bit mask to keep / remove all old / new bits.
 421          */
 422         majorasbitmask = (1L << len) - 1;
 423
 424         /*
 425          * If the new value is smaller than the corresponding bits of the last
 426          * timestamp, we assume an overflow of the compact representation.
 427          */
 428         newval = timestampDef.getValue();
 429         if (newval < (lastTimestamp & majorasbitmask)) {
 430             newval = newval + (1L << len);
 431         }
 432
 433         /* Keep only the high bits of the old value */
 434         lastTimestamp = lastTimestamp & ~majorasbitmask;
 435
 436         /* Then add the low bits of the new value */
 437         lastTimestamp = lastTimestamp + newval;
 438
 439         return lastTimestamp;
 440     }
 441
 442     @Override
 443     public Definition lookupDefinition(String lookupPath) {
 444         return null;
 445     }
 446 }