| 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; |
| 14 | |
| 15 | import java.io.*; |
| 16 | import java.util.ArrayList; |
| 17 | import java.util.Arrays; |
| 18 | import java.util.Collections; |
| 19 | import java.util.List; |
| 20 | |
| 21 | import org.eclipse.linuxtools.tmf.core.exceptions.AttributeNotFoundException; |
| 22 | import org.eclipse.linuxtools.tmf.core.exceptions.StateValueTypeException; |
| 23 | import org.eclipse.linuxtools.tmf.core.exceptions.TimeRangeException; |
| 24 | import org.eclipse.linuxtools.tmf.core.statevalue.TmfStateValue; |
| 25 | |
| 26 | /** |
| 27 | * The Attribute Tree is the /proc-like filesystem used to organize attributes. |
| 28 | * Each node of this tree is both like a file and a directory in the |
| 29 | * "file system". |
| 30 | * |
| 31 | * @author alexmont |
| 32 | * |
| 33 | */ |
| 34 | public final class AttributeTree { |
| 35 | |
| 36 | /* "Magic number" for attribute tree files or file sections */ |
| 37 | private static final int ATTRIB_TREE_MAGIC_NUMBER = 0x06EC3671; |
| 38 | |
| 39 | private final StateSystem ss; |
| 40 | private final List<Attribute> attributeList; |
| 41 | private final Attribute attributeTreeRoot; |
| 42 | |
| 43 | /** |
| 44 | * Standard constructor, create a new empty Attribute Tree |
| 45 | * |
| 46 | * @param ss |
| 47 | * The StateSystem to which this AT is attached |
| 48 | */ |
| 49 | public AttributeTree(StateSystem ss) { |
| 50 | this.ss = ss; |
| 51 | this.attributeList = Collections.synchronizedList(new ArrayList<Attribute>()); |
| 52 | this.attributeTreeRoot = new AlphaNumAttribute(null, "root", -1); //$NON-NLS-1$ |
| 53 | } |
| 54 | |
| 55 | /** |
| 56 | * "Existing file" constructor. Builds an attribute tree from a |
| 57 | * "mapping file" or mapping section previously saved somewhere. |
| 58 | * |
| 59 | * @param ss |
| 60 | * StateSystem to which this AT is attached |
| 61 | * @param fis |
| 62 | * File stream where to read the AT information. Make sure it's |
| 63 | * sought at the right place! |
| 64 | * @throws IOException |
| 65 | * If there is a problem reading from the file stream |
| 66 | */ |
| 67 | public AttributeTree(StateSystem ss, FileInputStream fis) throws IOException { |
| 68 | this(ss); |
| 69 | DataInputStream in = new DataInputStream(new BufferedInputStream(fis)); |
| 70 | |
| 71 | /* Message for exceptions, shouldn't be externalized */ |
| 72 | final String errorMessage = "The attribute tree file section is either invalid or corrupted."; //$NON-NLS-1$ |
| 73 | |
| 74 | ArrayList<String[]> list = new ArrayList<>(); |
| 75 | byte[] curByteArray; |
| 76 | String curFullString; |
| 77 | String[] curStringArray; |
| 78 | int res, remain, size; |
| 79 | int expectedSize = 0; |
| 80 | int total = 0; |
| 81 | |
| 82 | /* Read the header of the Attribute Tree file (or file section) */ |
| 83 | res = in.readInt(); /* Magic number */ |
| 84 | if (res != ATTRIB_TREE_MAGIC_NUMBER) { |
| 85 | throw new IOException(errorMessage); |
| 86 | } |
| 87 | |
| 88 | /* Expected size of the section */ |
| 89 | expectedSize = in.readInt(); |
| 90 | if (expectedSize <= 12) { |
| 91 | throw new IOException(errorMessage); |
| 92 | } |
| 93 | |
| 94 | /* How many entries we have to read */ |
| 95 | remain = in.readInt(); |
| 96 | total += 12; |
| 97 | |
| 98 | /* Read each entry */ |
| 99 | for (; remain > 0; remain--) { |
| 100 | /* Read the first byte = the size of the entry */ |
| 101 | size = in.readByte(); |
| 102 | curByteArray = new byte[size]; |
| 103 | res = in.read(curByteArray); |
| 104 | if (res != size) { |
| 105 | throw new IOException(errorMessage); |
| 106 | } |
| 107 | |
| 108 | /* |
| 109 | * Go buffer -> byteArray -> String -> String[] -> insert in list. |
| 110 | * bleh |
| 111 | */ |
| 112 | curFullString = new String(curByteArray); |
| 113 | curStringArray = curFullString.split("/"); //$NON-NLS-1$ |
| 114 | list.add(curStringArray); |
| 115 | |
| 116 | /* Read the 0'ed confirmation byte */ |
| 117 | res = in.readByte(); |
| 118 | if (res != 0) { |
| 119 | throw new IOException(errorMessage); |
| 120 | } |
| 121 | total += curByteArray.length + 2; |
| 122 | } |
| 123 | |
| 124 | if (total != expectedSize) { |
| 125 | throw new IOException(errorMessage); |
| 126 | } |
| 127 | |
| 128 | /* |
| 129 | * Now we have 'list', the ArrayList of String arrays representing all |
| 130 | * the attributes. Simply create attributes the normal way from them. |
| 131 | */ |
| 132 | for (String[] attrib : list) { |
| 133 | this.getQuarkAndAdd(-1, attrib); |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | /** |
| 138 | * Tell the Attribute Tree to write itself somewhere in a file. |
| 139 | * |
| 140 | * @param file |
| 141 | * The file to write to |
| 142 | * @param pos |
| 143 | * The position (in bytes) in the file where to write |
| 144 | * @return The total number of bytes written. |
| 145 | */ |
| 146 | public int writeSelf(File file, long pos) { |
| 147 | int total = 0; |
| 148 | byte[] curByteArray; |
| 149 | |
| 150 | try (RandomAccessFile raf = new RandomAccessFile(file, "rw");) { //$NON-NLS-1$ |
| 151 | raf.seek(pos); |
| 152 | |
| 153 | /* Write the almost-magic number */ |
| 154 | raf.writeInt(ATTRIB_TREE_MAGIC_NUMBER); |
| 155 | |
| 156 | /* Placeholder for the total size of the section... */ |
| 157 | raf.writeInt(-8000); |
| 158 | |
| 159 | /* Write the number of entries */ |
| 160 | raf.writeInt(this.attributeList.size()); |
| 161 | total += 12; |
| 162 | |
| 163 | /* Write the attributes themselves */ |
| 164 | for (Attribute entry : this.attributeList) { |
| 165 | curByteArray = entry.getFullAttributeName().getBytes(); |
| 166 | if (curByteArray.length > Byte.MAX_VALUE) { |
| 167 | throw new IOException("Attribute with name \"" //$NON-NLS-1$ |
| 168 | + Arrays.toString(curByteArray) + "\" is too long."); //$NON-NLS-1$ |
| 169 | } |
| 170 | /* Write the first byte = size of the array */ |
| 171 | raf.writeByte((byte) curByteArray.length); |
| 172 | |
| 173 | /* Write the array itself */ |
| 174 | raf.write(curByteArray); |
| 175 | |
| 176 | /* Write the 0'ed byte */ |
| 177 | raf.writeByte((byte) 0); |
| 178 | |
| 179 | total += curByteArray.length + 2; |
| 180 | } |
| 181 | |
| 182 | /* Now go back and write the actual size of this section */ |
| 183 | raf.seek(pos + 4); |
| 184 | raf.writeInt(total); |
| 185 | |
| 186 | } catch (IOException e) { |
| 187 | e.printStackTrace(); |
| 188 | } |
| 189 | return total; |
| 190 | } |
| 191 | |
| 192 | /** |
| 193 | * Return the number of attributes this system as seen so far. Note that |
| 194 | * this also equals the integer value (quark) the next added attribute will |
| 195 | * have. |
| 196 | * |
| 197 | * @return The current number of attributes in the tree |
| 198 | */ |
| 199 | public int getNbAttributes() { |
| 200 | return attributeList.size(); |
| 201 | } |
| 202 | |
| 203 | /** |
| 204 | * Get the quark for a given attribute path. No new attribute will be |
| 205 | * created : if the specified path does not exist, throw an error. |
| 206 | * |
| 207 | * @param startingNodeQuark |
| 208 | * The quark of the attribute from which relative queries will |
| 209 | * start. Use '-1' to start at the root node. |
| 210 | * @param subPath |
| 211 | * The path to the attribute, relative to the starting node. |
| 212 | * @return The quark of the specified attribute |
| 213 | * @throws AttributeNotFoundException |
| 214 | * If the specified path was not found |
| 215 | */ |
| 216 | public int getQuarkDontAdd(int startingNodeQuark, String... subPath) |
| 217 | throws AttributeNotFoundException { |
| 218 | assert (startingNodeQuark >= -1); |
| 219 | |
| 220 | Attribute prevNode; |
| 221 | |
| 222 | /* If subPath is empty, simply return the starting quark */ |
| 223 | if (subPath == null || subPath.length == 0) { |
| 224 | return startingNodeQuark; |
| 225 | } |
| 226 | |
| 227 | /* Get the "starting node" */ |
| 228 | if (startingNodeQuark == -1) { |
| 229 | prevNode = attributeTreeRoot; |
| 230 | } else { |
| 231 | prevNode = attributeList.get(startingNodeQuark); |
| 232 | } |
| 233 | |
| 234 | int knownQuark = prevNode.getSubAttributeQuark(subPath); |
| 235 | if (knownQuark == -1) { |
| 236 | /* |
| 237 | * The attribute doesn't exist, but we have been specified to NOT |
| 238 | * add any new attributes. |
| 239 | */ |
| 240 | throw new AttributeNotFoundException(); |
| 241 | } |
| 242 | /* |
| 243 | * The attribute was already existing, return the quark of that |
| 244 | * attribute |
| 245 | */ |
| 246 | return knownQuark; |
| 247 | } |
| 248 | |
| 249 | /** |
| 250 | * Get the quark of a given attribute path. If that specified path does not |
| 251 | * exist, it will be created (and the quark that was just created will be |
| 252 | * returned). |
| 253 | * |
| 254 | * @param startingNodeQuark |
| 255 | * The quark of the attribute from which relative queries will |
| 256 | * start. Use '-1' to start at the root node. |
| 257 | * @param subPath |
| 258 | * The path to the attribute, relative to the starting node. |
| 259 | * @return The quark of the attribute represented by the path |
| 260 | */ |
| 261 | public synchronized int getQuarkAndAdd(int startingNodeQuark, String... subPath) { |
| 262 | // FIXME synchronized here is probably quite costly... maybe only locking |
| 263 | // the "for" would be enough? |
| 264 | assert (subPath != null && subPath.length > 0); |
| 265 | assert (startingNodeQuark >= -1); |
| 266 | |
| 267 | Attribute nextNode = null; |
| 268 | Attribute prevNode; |
| 269 | |
| 270 | /* Get the "starting node" */ |
| 271 | if (startingNodeQuark == -1) { |
| 272 | prevNode = attributeTreeRoot; |
| 273 | } else { |
| 274 | prevNode = attributeList.get(startingNodeQuark); |
| 275 | } |
| 276 | |
| 277 | int knownQuark = prevNode.getSubAttributeQuark(subPath); |
| 278 | if (knownQuark == -1) { |
| 279 | /* |
| 280 | * The attribute was not in the table previously, and we want to add |
| 281 | * it |
| 282 | */ |
| 283 | for (String curDirectory : subPath) { |
| 284 | nextNode = prevNode.getSubAttributeNode(curDirectory); |
| 285 | if (nextNode == null) { |
| 286 | /* This is where we need to start adding */ |
| 287 | nextNode = new AlphaNumAttribute(prevNode, curDirectory, |
| 288 | attributeList.size()); |
| 289 | prevNode.addSubAttribute(nextNode); |
| 290 | attributeList.add(nextNode); |
| 291 | ss.addEmptyAttribute(); |
| 292 | } |
| 293 | prevNode = nextNode; |
| 294 | } |
| 295 | /* |
| 296 | * Insert an initial null value for this attribute in the state |
| 297 | * system (in case the state provider doesn't set one). |
| 298 | */ |
| 299 | final int newAttrib = attributeList.size() - 1; |
| 300 | try { |
| 301 | ss.modifyAttribute(ss.getStartTime(), TmfStateValue.nullValue(), newAttrib); |
| 302 | } catch (TimeRangeException e) { |
| 303 | /* Should not happen, we're inserting at ss's start time */ |
| 304 | throw new IllegalStateException(e); |
| 305 | } catch (AttributeNotFoundException e) { |
| 306 | /* Should not happen, we just created this attribute! */ |
| 307 | throw new IllegalStateException(e); |
| 308 | } catch (StateValueTypeException e) { |
| 309 | /* Should not happen, there is no existing state value, and the |
| 310 | * one we insert is a null value anyway. */ |
| 311 | throw new IllegalStateException(e); |
| 312 | } |
| 313 | |
| 314 | return newAttrib; |
| 315 | } |
| 316 | /* |
| 317 | * The attribute was already existing, return the quark of that |
| 318 | * attribute |
| 319 | */ |
| 320 | return knownQuark; |
| 321 | } |
| 322 | |
| 323 | /** |
| 324 | * Returns the sub-attributes of the quark passed in parameter |
| 325 | * |
| 326 | * @param attributeQuark |
| 327 | * The quark of the attribute to print the sub-attributes of. |
| 328 | * @param recursive |
| 329 | * Should the query be recursive or not? If false, only children |
| 330 | * one level deep will be returned. If true, all descendants will |
| 331 | * be returned (depth-first search) |
| 332 | * @return The list of quarks representing the children attributes |
| 333 | * @throws AttributeNotFoundException |
| 334 | * If 'attributeQuark' is invalid, or if there is no attrbiute |
| 335 | * associated to it. |
| 336 | */ |
| 337 | public List<Integer> getSubAttributes(int attributeQuark, boolean recursive) |
| 338 | throws AttributeNotFoundException { |
| 339 | List<Integer> listOfChildren = new ArrayList<>(); |
| 340 | Attribute startingAttribute; |
| 341 | |
| 342 | /* Check if the quark is valid */ |
| 343 | if (attributeQuark < -1 || attributeQuark >= attributeList.size()) { |
| 344 | throw new AttributeNotFoundException(); |
| 345 | } |
| 346 | |
| 347 | /* Set up the node from which we'll start the search */ |
| 348 | if (attributeQuark == -1) { |
| 349 | startingAttribute = attributeTreeRoot; |
| 350 | } else { |
| 351 | startingAttribute = attributeList.get(attributeQuark); |
| 352 | } |
| 353 | |
| 354 | /* Iterate through the sub-attributes and add them to the list */ |
| 355 | addSubAttributes(listOfChildren, startingAttribute, recursive); |
| 356 | |
| 357 | return listOfChildren; |
| 358 | } |
| 359 | |
| 360 | private void addSubAttributes(List<Integer> list, Attribute curAttribute, |
| 361 | boolean recursive) { |
| 362 | for (Attribute childNode : curAttribute.getSubAttributes()) { |
| 363 | list.add(childNode.getQuark()); |
| 364 | if (recursive) { |
| 365 | addSubAttributes(list, childNode, true); |
| 366 | } |
| 367 | } |
| 368 | } |
| 369 | |
| 370 | /** |
| 371 | * Get then base name of an attribute specified by a quark. |
| 372 | * |
| 373 | * @param quark |
| 374 | * The quark of the attribute |
| 375 | * @return The (base) name of the attribute |
| 376 | */ |
| 377 | public String getAttributeName(int quark) { |
| 378 | return attributeList.get(quark).getName(); |
| 379 | } |
| 380 | |
| 381 | /** |
| 382 | * Get the full path name of an attribute specified by a quark. |
| 383 | * |
| 384 | * @param quark |
| 385 | * The quark of the attribute |
| 386 | * @return The full path name of the attribute |
| 387 | */ |
| 388 | public String getFullAttributeName(int quark) { |
| 389 | if (quark >= attributeList.size() || quark < 0) { |
| 390 | return null; |
| 391 | } |
| 392 | return attributeList.get(quark).getFullAttributeName(); |
| 393 | } |
| 394 | |
| 395 | /** |
| 396 | * Debug-print all the attributes in the tree. |
| 397 | * |
| 398 | * @param writer |
| 399 | * The writer where to print the output |
| 400 | */ |
| 401 | public void debugPrint(PrintWriter writer) { |
| 402 | attributeTreeRoot.debugPrint(writer); |
| 403 | } |
| 404 | |
| 405 | } |