| 1 | /******************************************************************************* |
| 2 | * Copyright (c) 2012, 2013 Ericsson |
| 3 | * Copyright (c) 2010, 2011 École Polytechnique de Montréal |
| 4 | * Copyright (c) 2010, 2011 Alexandre Montplaisir <alexandre.montplaisir@gmail.com> |
| 5 | * |
| 6 | * All rights reserved. This program and the accompanying materials are |
| 7 | * made available under the terms of the Eclipse Public License v1.0 which |
| 8 | * accompanies this distribution, and is available at |
| 9 | * http://www.eclipse.org/legal/epl-v10.html |
| 10 | * |
| 11 | *******************************************************************************/ |
| 12 | |
| 13 | package org.eclipse.linuxtools.internal.tmf.core.statesystem.backends.historytree; |
| 14 | |
| 15 | import java.io.IOException; |
| 16 | import java.io.PrintWriter; |
| 17 | import java.nio.ByteBuffer; |
| 18 | import java.nio.ByteOrder; |
| 19 | import java.nio.channels.FileChannel; |
| 20 | import java.util.ArrayList; |
| 21 | import java.util.Collections; |
| 22 | import java.util.List; |
| 23 | |
| 24 | import org.eclipse.linuxtools.tmf.core.exceptions.TimeRangeException; |
| 25 | import org.eclipse.linuxtools.tmf.core.interval.ITmfStateInterval; |
| 26 | import org.eclipse.linuxtools.tmf.core.statevalue.TmfStateValue; |
| 27 | |
| 28 | /** |
| 29 | * The base class for all the types of nodes that go in the History Tree. |
| 30 | * |
| 31 | * @author alexmont |
| 32 | */ |
| 33 | abstract class HTNode { |
| 34 | |
| 35 | /** |
| 36 | * Size of an entry in the data section. |
| 37 | * |
| 38 | * 16 2 x Timevalue/long (interval start + end) |
| 39 | * + 4 int (key) |
| 40 | * + 1 byte (type) |
| 41 | * + 4 int (valueOffset) |
| 42 | */ |
| 43 | protected static final int DATA_ENTRY_SIZE = 25; |
| 44 | |
| 45 | /* Reference to the History Tree to whom this node belongs */ |
| 46 | private final HistoryTree ownerTree; |
| 47 | |
| 48 | /* Time range of this node */ |
| 49 | private final long nodeStart; |
| 50 | private long nodeEnd; |
| 51 | |
| 52 | /* Sequence number = position in the node section of the file */ |
| 53 | private final int sequenceNumber; |
| 54 | private int parentSequenceNumber; /* = -1 if this node is the root node */ |
| 55 | |
| 56 | /* Where the Strings section begins (from the start of the node */ |
| 57 | private int stringSectionOffset; |
| 58 | |
| 59 | /* True if this node is closed (and to be committed to disk) */ |
| 60 | private boolean isDone; |
| 61 | |
| 62 | /* Vector containing all the intervals contained in this node */ |
| 63 | private final List<HTInterval> intervals; |
| 64 | |
| 65 | HTNode(HistoryTree tree, int seqNumber, int parentSeqNumber, long start) { |
| 66 | this.ownerTree = tree; |
| 67 | this.nodeStart = start; |
| 68 | this.sequenceNumber = seqNumber; |
| 69 | this.parentSequenceNumber = parentSeqNumber; |
| 70 | |
| 71 | this.stringSectionOffset = ownerTree.getConfig().getBlockSize(); |
| 72 | this.isDone = false; |
| 73 | this.intervals = new ArrayList<HTInterval>(); |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * Reader factory constructor. Build a Node object (of the right type) by |
| 78 | * reading a block in the file. |
| 79 | * |
| 80 | * @param tree |
| 81 | * Reference to the HT which will own this node |
| 82 | * @param fc |
| 83 | * FileChannel to the history file, ALREADY SEEKED at the start |
| 84 | * of the node. |
| 85 | * @throws IOException |
| 86 | */ |
| 87 | static final HTNode readNode(HistoryTree tree, FileChannel fc) |
| 88 | throws IOException { |
| 89 | HTNode newNode = null; |
| 90 | int res, i; |
| 91 | |
| 92 | ByteBuffer buffer = ByteBuffer.allocate(tree.getConfig().getBlockSize()); |
| 93 | buffer.order(ByteOrder.LITTLE_ENDIAN); |
| 94 | buffer.clear(); |
| 95 | res = fc.read(buffer); |
| 96 | assert (res == tree.getConfig().getBlockSize()); |
| 97 | buffer.flip(); |
| 98 | |
| 99 | /* Read the common header part */ |
| 100 | byte type = buffer.get(); |
| 101 | long start = buffer.getLong(); |
| 102 | long end = buffer.getLong(); |
| 103 | int seqNb = buffer.getInt(); |
| 104 | int parentSeqNb = buffer.getInt(); |
| 105 | int intervalCount = buffer.getInt(); |
| 106 | int stringSectionOffset = buffer.getInt(); |
| 107 | boolean done = byteToBool(buffer.get()); |
| 108 | |
| 109 | /* Now the rest of the header depends on the node type */ |
| 110 | switch (type) { |
| 111 | case 1: |
| 112 | /* Core nodes */ |
| 113 | newNode = new CoreNode(tree, seqNb, parentSeqNb, start); |
| 114 | newNode.readSpecificHeader(buffer); |
| 115 | break; |
| 116 | |
| 117 | // TODO implement other node types |
| 118 | // case 2: |
| 119 | // /* Leaf nodes */ |
| 120 | // |
| 121 | // |
| 122 | // |
| 123 | // case 3: |
| 124 | // /* "Claudette" (extended) nodes */ |
| 125 | // |
| 126 | |
| 127 | default: |
| 128 | /* Unrecognized node type */ |
| 129 | throw new IOException(); |
| 130 | } |
| 131 | |
| 132 | /* |
| 133 | * At this point, we should be done reading the header and 'buffer' |
| 134 | * should only have the intervals left |
| 135 | */ |
| 136 | for (i = 0; i < intervalCount; i++) { |
| 137 | newNode.intervals.add(HTInterval.readFrom(buffer)); |
| 138 | } |
| 139 | |
| 140 | /* Assign the node's other information we have read previously */ |
| 141 | newNode.nodeEnd = end; |
| 142 | newNode.stringSectionOffset = stringSectionOffset; |
| 143 | newNode.isDone = done; |
| 144 | |
| 145 | return newNode; |
| 146 | } |
| 147 | |
| 148 | final void writeSelf(FileChannel fc) throws IOException { |
| 149 | final int blockSize = ownerTree.getConfig().getBlockSize(); |
| 150 | int curStringsEntryEndPos = blockSize; |
| 151 | |
| 152 | ByteBuffer buffer = ByteBuffer.allocate(blockSize); |
| 153 | buffer.order(ByteOrder.LITTLE_ENDIAN); |
| 154 | buffer.clear(); |
| 155 | |
| 156 | /* Write the common header part */ |
| 157 | buffer.put(this.getNodeType()); |
| 158 | buffer.putLong(nodeStart); |
| 159 | buffer.putLong(nodeEnd); |
| 160 | buffer.putInt(sequenceNumber); |
| 161 | buffer.putInt(parentSequenceNumber); |
| 162 | buffer.putInt(intervals.size()); |
| 163 | buffer.putInt(stringSectionOffset); |
| 164 | buffer.put(boolToByte(isDone)); |
| 165 | |
| 166 | /* Now call the inner method to write the specific header part */ |
| 167 | this.writeSpecificHeader(buffer); |
| 168 | |
| 169 | /* Back to us, we write the intervals */ |
| 170 | for (HTInterval interval : intervals) { |
| 171 | int size = interval.writeInterval(buffer, curStringsEntryEndPos); |
| 172 | curStringsEntryEndPos -= size; |
| 173 | } |
| 174 | |
| 175 | /* |
| 176 | * Write padding between the end of the Data section and the start of |
| 177 | * the Strings section (needed to fill the node in case there is no |
| 178 | * Strings section) |
| 179 | */ |
| 180 | while (buffer.position() < stringSectionOffset) { |
| 181 | buffer.put((byte) 0); |
| 182 | } |
| 183 | |
| 184 | /* |
| 185 | * If the offsets were right, the size of the Strings section should be |
| 186 | * == to the expected size |
| 187 | */ |
| 188 | assert (curStringsEntryEndPos == stringSectionOffset); |
| 189 | |
| 190 | /* Finally, write everything in the Buffer to disk */ |
| 191 | |
| 192 | // if we don't do this, flip() will lose what's after. |
| 193 | buffer.position(blockSize); |
| 194 | |
| 195 | buffer.flip(); |
| 196 | int res = fc.write(buffer); |
| 197 | assert (res == blockSize); |
| 198 | } |
| 199 | |
| 200 | // ------------------------------------------------------------------------ |
| 201 | // Accessors |
| 202 | // ------------------------------------------------------------------------ |
| 203 | |
| 204 | protected HistoryTree getTree() { |
| 205 | return ownerTree; |
| 206 | } |
| 207 | |
| 208 | long getNodeStart() { |
| 209 | return nodeStart; |
| 210 | } |
| 211 | |
| 212 | long getNodeEnd() { |
| 213 | if (this.isDone) { |
| 214 | return nodeEnd; |
| 215 | } |
| 216 | return 0; |
| 217 | } |
| 218 | |
| 219 | int getSequenceNumber() { |
| 220 | return sequenceNumber; |
| 221 | } |
| 222 | |
| 223 | int getParentSequenceNumber() { |
| 224 | return parentSequenceNumber; |
| 225 | } |
| 226 | |
| 227 | /** |
| 228 | * Change this node's parent. Used when we create a new root node for |
| 229 | * example. |
| 230 | */ |
| 231 | void setParentSequenceNumber(int newParent) { |
| 232 | parentSequenceNumber = newParent; |
| 233 | } |
| 234 | |
| 235 | boolean isDone() { |
| 236 | return isDone; |
| 237 | } |
| 238 | |
| 239 | /** |
| 240 | * Add an interval to this node |
| 241 | * |
| 242 | * @param newInterval |
| 243 | */ |
| 244 | void addInterval(HTInterval newInterval) { |
| 245 | /* Just in case, but should be checked before even calling this function */ |
| 246 | assert (newInterval.getIntervalSize() <= this.getNodeFreeSpace()); |
| 247 | |
| 248 | intervals.add(newInterval); |
| 249 | |
| 250 | /* Update the in-node offset "pointer" */ |
| 251 | stringSectionOffset -= (newInterval.getStringsEntrySize()); |
| 252 | } |
| 253 | |
| 254 | /** |
| 255 | * We've received word from the containerTree that newest nodes now exist to |
| 256 | * our right. (Puts isDone = true and sets the endtime) |
| 257 | * |
| 258 | * @param endtime |
| 259 | * The nodeEnd time that the node will have |
| 260 | * @throws TimeRangeException |
| 261 | */ |
| 262 | void closeThisNode(long endtime) { |
| 263 | assert (endtime >= this.nodeStart); |
| 264 | |
| 265 | if (intervals.size() > 0) { |
| 266 | /* |
| 267 | * Sort the intervals by ascending order of their end time. This |
| 268 | * speeds up lookups a bit |
| 269 | */ |
| 270 | Collections.sort(intervals); |
| 271 | |
| 272 | /* |
| 273 | * Make sure there are no intervals in this node with their EndTime |
| 274 | * > the one requested. Only need to check the last one since they |
| 275 | * are now sorted |
| 276 | */ |
| 277 | assert (endtime >= intervals.get(intervals.size() - 1).getEndTime()); |
| 278 | } |
| 279 | |
| 280 | this.isDone = true; |
| 281 | this.nodeEnd = endtime; |
| 282 | return; |
| 283 | } |
| 284 | |
| 285 | /** |
| 286 | * The method to fill up the stateInfo (passed on from the Current State |
| 287 | * Tree when it does a query on the SHT). We'll replace the data in that |
| 288 | * vector with whatever relevant we can find from this node |
| 289 | * |
| 290 | * @param stateInfo |
| 291 | * The same stateInfo that comes from SHT's doQuery() |
| 292 | * @param t |
| 293 | * The timestamp for which the query is for. Only return |
| 294 | * intervals that intersect t. |
| 295 | * @throws TimeRangeException |
| 296 | */ |
| 297 | void writeInfoFromNode(List<ITmfStateInterval> stateInfo, long t) |
| 298 | throws TimeRangeException { |
| 299 | assert (this.isDone); // not sure this will always be the case... |
| 300 | int startIndex; |
| 301 | |
| 302 | if (intervals.size() == 0) { |
| 303 | return; |
| 304 | } |
| 305 | startIndex = getStartIndexFor(t); |
| 306 | |
| 307 | for (int i = startIndex; i < intervals.size(); i++) { |
| 308 | /* |
| 309 | * Now we only have to compare the Start times, since we now the End |
| 310 | * times necessarily fit |
| 311 | */ |
| 312 | if (intervals.get(i).getStartTime() <= t) { |
| 313 | stateInfo.set(intervals.get(i).getAttribute(), intervals.get(i)); |
| 314 | } |
| 315 | } |
| 316 | return; |
| 317 | } |
| 318 | |
| 319 | /** |
| 320 | * Get a single Interval from the information in this node If the |
| 321 | * key/timestamp pair cannot be found, we return null. |
| 322 | * |
| 323 | * @param key |
| 324 | * @param t |
| 325 | * @return The Interval containing the information we want, or null if it |
| 326 | * wasn't found |
| 327 | * @throws TimeRangeException |
| 328 | */ |
| 329 | HTInterval getRelevantInterval(int key, long t) throws TimeRangeException { |
| 330 | assert (this.isDone); |
| 331 | int startIndex; |
| 332 | HTInterval curInterval; |
| 333 | |
| 334 | if (intervals.size() == 0) { |
| 335 | return null; |
| 336 | } |
| 337 | |
| 338 | startIndex = getStartIndexFor(t); |
| 339 | |
| 340 | for (int i = startIndex; i < intervals.size(); i++) { |
| 341 | curInterval = intervals.get(i); |
| 342 | if (curInterval.getAttribute() == key |
| 343 | && curInterval.getStartTime() <= t |
| 344 | && curInterval.getEndTime() >= t) { |
| 345 | return curInterval; |
| 346 | } |
| 347 | } |
| 348 | /* We didn't find the relevant information in this node */ |
| 349 | return null; |
| 350 | } |
| 351 | |
| 352 | private int getStartIndexFor(long t) throws TimeRangeException { |
| 353 | HTInterval dummy; |
| 354 | int index; |
| 355 | |
| 356 | /* |
| 357 | * Since the intervals are sorted by end time, we can skip all the ones |
| 358 | * at the beginning whose end times are smaller than 't'. Java does |
| 359 | * provides a .binarySearch method, but its API is quite weird... |
| 360 | */ |
| 361 | dummy = new HTInterval(0, t, 0, TmfStateValue.nullValue()); |
| 362 | index = Collections.binarySearch(intervals, dummy); |
| 363 | |
| 364 | if (index < 0) { |
| 365 | /* |
| 366 | * .binarySearch returns a negative number if the exact value was |
| 367 | * not found. Here we just want to know where to start searching, we |
| 368 | * don't care if the value is exact or not. |
| 369 | */ |
| 370 | index = -index - 1; |
| 371 | |
| 372 | } |
| 373 | |
| 374 | /* Sometimes binarySearch yields weird stuff... */ |
| 375 | if (index < 0) { |
| 376 | index = 0; |
| 377 | } |
| 378 | if (index >= intervals.size()) { |
| 379 | index = intervals.size() - 1; |
| 380 | } |
| 381 | |
| 382 | /* |
| 383 | * Another API quirkiness, the returned index is the one of the *last* |
| 384 | * element of a series of equal endtimes, which happens sometimes. We |
| 385 | * want the *first* element of such a series, to read through them |
| 386 | * again. |
| 387 | */ |
| 388 | while (index > 0 |
| 389 | && intervals.get(index - 1).compareTo(intervals.get(index)) == 0) { |
| 390 | index--; |
| 391 | } |
| 392 | |
| 393 | return index; |
| 394 | } |
| 395 | |
| 396 | /** |
| 397 | * @return The offset, within the node, where the Data section ends |
| 398 | */ |
| 399 | private int getDataSectionEndOffset() { |
| 400 | return this.getTotalHeaderSize() + HTNode.DATA_ENTRY_SIZE * intervals.size(); |
| 401 | } |
| 402 | |
| 403 | /** |
| 404 | * Returns the free space in the node, which is simply put, the |
| 405 | * stringSectionOffset - dataSectionOffset |
| 406 | */ |
| 407 | int getNodeFreeSpace() { |
| 408 | return stringSectionOffset - this.getDataSectionEndOffset(); |
| 409 | } |
| 410 | |
| 411 | /** |
| 412 | * Returns the current space utilisation of this node, as a percentage. |
| 413 | * (used space / total usable space, which excludes the header) |
| 414 | */ |
| 415 | long getNodeUsagePRC() { |
| 416 | final int blockSize = ownerTree.getConfig().getBlockSize(); |
| 417 | float freePercent = (float) this.getNodeFreeSpace() |
| 418 | / (float) (blockSize - this.getTotalHeaderSize()) |
| 419 | * 100F; |
| 420 | return (long) (100L - freePercent); |
| 421 | } |
| 422 | |
| 423 | protected static final byte boolToByte(boolean thebool) { |
| 424 | if (thebool) { |
| 425 | return (byte) 1; |
| 426 | } |
| 427 | return (byte) 0; |
| 428 | } |
| 429 | |
| 430 | static final boolean byteToBool(byte thebyte) { |
| 431 | return (thebyte == (byte) 1); |
| 432 | } |
| 433 | |
| 434 | /** |
| 435 | * @name Debugging functions |
| 436 | */ |
| 437 | |
| 438 | @SuppressWarnings("nls") |
| 439 | @Override |
| 440 | public String toString() { |
| 441 | /* Only used for debugging, shouldn't be externalized */ |
| 442 | StringBuffer buf = new StringBuffer("Node #" + sequenceNumber + ", "); |
| 443 | buf.append(this.toStringSpecific()); |
| 444 | buf.append(intervals.size() + " intervals (" + this.getNodeUsagePRC() |
| 445 | + "% used), "); |
| 446 | |
| 447 | buf.append("[" + this.nodeStart + " - "); |
| 448 | if (this.isDone) { |
| 449 | buf = buf.append("" + this.nodeEnd + "]"); |
| 450 | } else { |
| 451 | buf = buf.append("...]"); |
| 452 | } |
| 453 | return buf.toString(); |
| 454 | } |
| 455 | |
| 456 | /** |
| 457 | * Debugging function that prints out the contents of this node |
| 458 | * |
| 459 | * @param writer |
| 460 | * PrintWriter in which we will print the debug output |
| 461 | */ |
| 462 | @SuppressWarnings("nls") |
| 463 | void debugPrintIntervals(PrintWriter writer) { |
| 464 | /* Only used for debugging, shouldn't be externalized */ |
| 465 | writer.println("Node #" + sequenceNumber + ":"); |
| 466 | |
| 467 | /* Array of children */ |
| 468 | if (this.getNodeType() == 1) { /* Only Core Nodes can have children */ |
| 469 | CoreNode thisNode = (CoreNode) this; |
| 470 | writer.print(" " + thisNode.getNbChildren() + " children"); |
| 471 | if (thisNode.getNbChildren() >= 1) { |
| 472 | writer.print(": [ " + thisNode.getChild(0)); |
| 473 | for (int i = 1; i < thisNode.getNbChildren(); i++) { |
| 474 | writer.print(", " + thisNode.getChild(i)); |
| 475 | } |
| 476 | writer.print(']'); |
| 477 | } |
| 478 | writer.print('\n'); |
| 479 | } |
| 480 | |
| 481 | /* List of intervals in the node */ |
| 482 | writer.println(" Intervals contained:"); |
| 483 | for (int i = 0; i < intervals.size(); i++) { |
| 484 | writer.println(intervals.get(i).toString()); |
| 485 | } |
| 486 | writer.println('\n'); |
| 487 | } |
| 488 | |
| 489 | /** |
| 490 | * 1 - byte (type) |
| 491 | * |
| 492 | * 16 - 2x long (start time, end time) |
| 493 | * |
| 494 | * 16 - 4x int (seq number, parent seq number, intervalcount, strings |
| 495 | * section pos.) |
| 496 | * |
| 497 | * 1 - byte (done or not) |
| 498 | */ |
| 499 | protected static final int COMMON_HEADER_SIZE = 34; |
| 500 | |
| 501 | // ------------------------------------------------------------------------ |
| 502 | // Abstract methods |
| 503 | // ------------------------------------------------------------------------ |
| 504 | |
| 505 | protected abstract byte getNodeType(); |
| 506 | |
| 507 | protected abstract int getTotalHeaderSize(); |
| 508 | |
| 509 | protected abstract void readSpecificHeader(ByteBuffer buffer); |
| 510 | |
| 511 | protected abstract void writeSpecificHeader(ByteBuffer buffer); |
| 512 | |
| 513 | protected abstract String toStringSpecific(); |
| 514 | } |