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

   1 /*******************************************************************************
   2  * Copyright (c) 2011-2012 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
  13 package org.eclipse.linuxtools.ctf.core.trace;
  14
  15 import java.io.File;
  16 import java.io.FileInputStream;
  17 import java.io.FileNotFoundException;
  18 import java.io.FileReader;
  19 import java.io.IOException;
  20 import java.io.Reader;
  21 import java.io.StringReader;
  22 import java.nio.ByteBuffer;
  23 import java.nio.ByteOrder;
  24 import java.nio.channels.FileChannel;
  25 import java.util.Arrays;
  26 import java.util.UUID;
  27
  28 import org.antlr.runtime.ANTLRReaderStream;
  29 import org.antlr.runtime.CommonTokenStream;
  30 import org.antlr.runtime.RecognitionException;
  31 import org.antlr.runtime.tree.CommonTree;
  32 import org.eclipse.linuxtools.ctf.parser.CTFLexer;
  33 import org.eclipse.linuxtools.ctf.parser.CTFParser;
  34 import org.eclipse.linuxtools.ctf.parser.CTFParser.parse_return;
  35 import org.eclipse.linuxtools.internal.ctf.core.event.metadata.IOStructGen;
  36 import org.eclipse.linuxtools.internal.ctf.core.event.metadata.exceptions.ParseException;
  37
  38 /**
  39  * <b><u>Metadata</u></b>
  40  * <p>
  41  * Represents a metadata file
  42  */
  43 public class Metadata {
  44
  45     // ------------------------------------------------------------------------
  46     // Constants
  47     // ------------------------------------------------------------------------
  48
  49     /**
  50      * Name of the metadata file in the trace directory
  51      */
  52     final String METADATA_FILENAME = "metadata"; //$NON-NLS-1$
  53
  54     /**
  55      * Size of the metadata packet header, in bytes, computed by hand.
  56      */
  57     final int METADATA_PACKET_HEADER_SIZE = 37;
  58
  59     // ------------------------------------------------------------------------
  60     // Attributes
  61     // ------------------------------------------------------------------------
  62
  63     /**
  64      * Reference to the metadata file
  65      */
  66     private File metadataFile = null;
  67
  68     /**
  69      * Byte order as detected when reading the TSDL magic number.
  70      */
  71     private ByteOrder detectedByteOrder = null;
  72
  73     /**
  74      * The trace file to which belongs this metadata file.
  75      */
  76     private CTFTrace trace = null;
  77
  78     // ------------------------------------------------------------------------
  79     // Constructors
  80     // ------------------------------------------------------------------------
  81
  82     /**
  83      * Constructs a Metadata object.
  84      *
  85      * @param trace
  86      *            The trace to which belongs this metadata file.
  87      */
  88     public Metadata(CTFTrace trace) {
  89         this.trace = trace;
  90
  91         /* Path of metadata file = trace directory path + metadata filename */
  92         String metadataPath = trace.getTraceDirectory().getPath()
  93                 + Utils.SEPARATOR + METADATA_FILENAME;
  94
  95         /* Create a file reference to the metadata file */
  96         metadataFile = new File(metadataPath);
  97     }
  98
  99     // ------------------------------------------------------------------------
 100     // Getters/Setters/Predicates
 101     // ------------------------------------------------------------------------
 102
 103     /**
 104      * Returns the ByteOrder that was detected while parsing the metadata.
 105      *
 106      * @return The byte order.
 107      */
 108     public ByteOrder getDetectedByteOrder() {
 109         return detectedByteOrder;
 110     }
 111
 112     // ------------------------------------------------------------------------
 113     // Operations
 114     // ------------------------------------------------------------------------
 115
 116     /**
 117      * Parse the metadata file.
 118      *
 119      * @throws CTFReaderException
 120      */
 121     public void parse() throws CTFReaderException {
 122         CTFReaderException tempException = null;
 123
 124         FileInputStream fis = null;
 125         FileChannel metadataFileChannel = null;
 126
 127         /*
 128          * Reader. It will contain a StringReader if we are using packet-based
 129          * metadata and it will contain a FileReader if we have text-based
 130          * metadata.
 131          */
 132         Reader metadataTextInput = null;
 133
 134         try {
 135             fis = new FileInputStream(metadataFile);
 136             metadataFileChannel = fis.getChannel();
 137
 138             /* Check if metadata is packet-based */
 139             if (isPacketBased(metadataFileChannel)) {
 140                 /* Create StringBuffer to receive metadata text */
 141                 StringBuffer metadataText = new StringBuffer();
 142
 143                 /*
 144                  * Read metadata packet one by one, appending the text to the
 145                  * StringBuffer
 146                  */
 147                 MetadataPacketHeader packetHeader = readMetadataPacket(
 148                         metadataFileChannel, metadataText);
 149                 while (packetHeader != null) {
 150                     packetHeader = readMetadataPacket(metadataFileChannel,
 151                             metadataText);
 152                 }
 153
 154                 /* Wrap the metadata string with a StringReader */
 155                 metadataTextInput = new StringReader(metadataText.toString());
 156             } else {
 157                 /* Wrap the metadata file with a FileReader */
 158                 metadataTextInput = new FileReader(metadataFile);
 159             }
 160
 161             /* Create an ANTLR reader */
 162             ANTLRReaderStream antlrStream;
 163             antlrStream = new ANTLRReaderStream(metadataTextInput);
 164
 165             /* Parse the metadata text and get the AST */
 166             CTFLexer ctfLexer = new CTFLexer(antlrStream);
 167             CommonTokenStream tokens = new CommonTokenStream(ctfLexer);
 168             CTFParser ctfParser = new CTFParser(tokens, false);
 169             parse_return ret;
 170
 171             ret = ctfParser.parse();
 172
 173             CommonTree tree = (CommonTree) ret.getTree();
 174
 175             /* Generate IO structures (declarations) */
 176             IOStructGen gen = new IOStructGen(tree, trace);
 177             gen.generate();
 178
 179         } catch (FileNotFoundException e) {
 180             tempException = new CTFReaderException("Cannot find metadata file!"); //$NON-NLS-1$
 181         } catch (IOException e) {
 182             /* This would indicate a problem with the ANTLR library... */
 183             tempException = new CTFReaderException(e);
 184         } catch (ParseException e) {
 185             tempException = new CTFReaderException(e);
 186         } catch (RecognitionException e) {
 187             /*
 188              * We don't want to expose this ANTLR-specific exception type to the
 189              * outside..
 190              */
 191             tempException = new CTFReaderException(e);
 192         }
 193
 194         /* Ghetto resource management. Java 7 will deliver us from this... */
 195         if (metadataTextInput != null) {
 196             try {
 197                 metadataTextInput.close();
 198             } catch (IOException e) {
 199                 // Do nothing
 200             }
 201         }
 202         if (metadataFileChannel != null) {
 203             try {
 204                 metadataFileChannel.close();
 205             } catch (IOException e) {
 206                 // Do nothing
 207             }
 208         }
 209         if (fis != null) {
 210             try {
 211                 fis.close();
 212             } catch (IOException e) {
 213                 // Do nothing
 214             }
 215         }
 216
 217         if (tempException != null) {
 218             throw tempException;
 219         }
 220     }
 221
 222     /**
 223      * Determines whether the metadata file is packet-based by looking at the
 224      * TSDL magic number. If it is packet-based, it also gives information about
 225      * the endianness of the trace using the detectedByteOrder attribute.
 226      *
 227      * @param metadataFileChannel
 228      *            FileChannel of the metadata file.
 229      * @return True if the metadata is packet-based.
 230      * @throws CTFReaderException
 231      */
 232     private boolean isPacketBased(FileChannel metadataFileChannel)
 233             throws CTFReaderException {
 234         /*
 235          * Create a ByteBuffer to read the TSDL magic number (default is big
 236          * endian)
 237          */
 238         ByteBuffer magicByteBuffer = ByteBuffer.allocate(Utils.TSDL_MAGIC_LEN);
 239
 240         /* Read without changing file position */
 241         try {
 242             metadataFileChannel.read(magicByteBuffer, 0);
 243         } catch (IOException e) {
 244             throw new CTFReaderException(
 245                     "Unable to read metadata file channel."); //$NON-NLS-1$
 246         }
 247
 248         /* Get the first int from the file */
 249         int magic = magicByteBuffer.getInt(0);
 250
 251         /* Check if it matches */
 252         if (Utils.TSDL_MAGIC == magic) {
 253             detectedByteOrder = ByteOrder.BIG_ENDIAN;
 254             return true;
 255         }
 256
 257         /* Try the same thing, but with little endian */
 258         magicByteBuffer.order(ByteOrder.LITTLE_ENDIAN);
 259         magic = magicByteBuffer.getInt(0);
 260
 261         if (Utils.TSDL_MAGIC == magic) {
 262             detectedByteOrder = ByteOrder.LITTLE_ENDIAN;
 263             return true;
 264         }
 265
 266         return false;
 267     }
 268
 269     /**
 270      * Reads a metadata packet from the given metadata FileChannel, do some
 271      * basic validation and append the text to the StringBuffer.
 272      *
 273      * @param metadataFileChannel
 274      *            Metadata FileChannel
 275      * @param metadataText
 276      *            StringBuffer to which the metadata text will be appended.
 277      * @return A structure describing the header of the metadata packet, or null
 278      *         if the end of the file is reached.
 279      * @throws CTFReaderException
 280      */
 281     private MetadataPacketHeader readMetadataPacket(
 282             FileChannel metadataFileChannel, StringBuffer metadataText)
 283             throws CTFReaderException {
 284         /* Allocate a ByteBuffer for the header */
 285         ByteBuffer headerByteBuffer = ByteBuffer.allocate(METADATA_PACKET_HEADER_SIZE);
 286
 287         /* Read the header */
 288         int nbBytesRead;
 289         try {
 290             nbBytesRead = metadataFileChannel.read(headerByteBuffer);
 291         } catch (IOException e) {
 292             throw new CTFReaderException("Error reading the metadata header."); //$NON-NLS-1$
 293         }
 294
 295         /* Return null if EOF */
 296         if (nbBytesRead < 0) {
 297             return null;
 298         }
 299
 300         /* Set ByteBuffer's position to 0 */
 301         headerByteBuffer.position(0);
 302
 303         /* Use byte order that was detected with the magic number */
 304         headerByteBuffer.order(detectedByteOrder);
 305
 306         assert (nbBytesRead == METADATA_PACKET_HEADER_SIZE);
 307
 308         MetadataPacketHeader header = new MetadataPacketHeader();
 309
 310         /* Read from the ByteBuffer */
 311         header.magic = headerByteBuffer.getInt();
 312         headerByteBuffer.get(header.uuid);
 313         header.checksum = headerByteBuffer.getInt();
 314         header.contentSize = headerByteBuffer.getInt();
 315         header.packetSize = headerByteBuffer.getInt();
 316         header.compressionScheme = headerByteBuffer.get();
 317         header.encryptionScheme = headerByteBuffer.get();
 318         header.checksumScheme = headerByteBuffer.get();
 319         header.ctfMajorVersion = headerByteBuffer.get();
 320         header.ctfMinorVersion = headerByteBuffer.get();
 321
 322         /* Check TSDL magic number */
 323         if (header.magic != Utils.TSDL_MAGIC) {
 324             throw new CTFReaderException("TSDL magic number does not match"); //$NON-NLS-1$
 325         }
 326
 327         /* Check UUID */
 328         UUID uuid = Utils.makeUUID(header.uuid);
 329         if (!trace.UUIDIsSet()) {
 330             trace.setUUID(uuid);
 331         } else {
 332             if (!trace.getUUID().equals(uuid)) {
 333                 throw new CTFReaderException("UUID mismatch"); //$NON-NLS-1$
 334             }
 335         }
 336
 337         /* Extract the text from the packet */
 338         int payloadSize = ((header.contentSize / 8) - METADATA_PACKET_HEADER_SIZE);
 339         int skipSize = (header.packetSize - header.contentSize) / 8;
 340
 341         /* Read the payload + the padding in a ByteBuffer */
 342         ByteBuffer payloadByteBuffer = ByteBuffer.allocateDirect(payloadSize
 343                 + skipSize);
 344         try {
 345             metadataFileChannel.read(payloadByteBuffer);
 346         } catch (IOException e) {
 347             throw new CTFReaderException(
 348                     "Error reading metadata packet payload."); //$NON-NLS-1$
 349         }
 350         payloadByteBuffer.rewind();
 351
 352         /* Read only the payload from the ByteBuffer into a byte array */
 353         byte payloadByteArray[] = new byte[payloadByteBuffer.remaining()];
 354         payloadByteBuffer.get(payloadByteArray, 0, payloadSize);
 355
 356         /* Convert the byte array to a String */
 357         String str = new String(payloadByteArray, 0, payloadSize);
 358
 359         /* Append it to the existing metadata */
 360         metadataText.append(str);
 361
 362         return header;
 363     }
 364
 365     static class MetadataPacketHeader {
 366
 367         public int magic;
 368         public byte uuid[] = new byte[16];
 369         public int checksum;
 370         public int contentSize;
 371         public int packetSize;
 372         public byte compressionScheme;
 373         public byte encryptionScheme;
 374         public byte checksumScheme;
 375         public byte ctfMajorVersion;
 376         public byte ctfMinorVersion;
 377
 378         @Override
 379         public String toString() {
 380             /* Only for debugging, shouldn't be externalized */
 381             /* Therefore it cannot be covered by test cases */
 382             return "MetadataPacketHeader [magic=0x" //$NON-NLS-1$
 383                     + Integer.toHexString(magic) + ", uuid=" //$NON-NLS-1$
 384                     + Arrays.toString(uuid) + ", checksum=" + checksum //$NON-NLS-1$
 385                     + ", contentSize=" + contentSize + ", packetSize=" //$NON-NLS-1$ //$NON-NLS-2$
 386                     + packetSize + ", compressionScheme=" + compressionScheme //$NON-NLS-1$
 387                     + ", encryptionScheme=" + encryptionScheme //$NON-NLS-1$
 388                     + ", checksumScheme=" + checksumScheme //$NON-NLS-1$
 389                     + ", ctfMajorVersion=" + ctfMajorVersion //$NON-NLS-1$
 390                     + ", ctfMinorVersion=" + ctfMinorVersion + ']'; //$NON-NLS-1$
 391         }
 392
 393     }
 394 }