| 1 | /******************************************************************************* |
| 2 | * Copyright (c) 2012 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.tmf.core.statesystem; |
| 14 | |
| 15 | import java.io.PrintWriter; |
| 16 | import java.util.LinkedList; |
| 17 | import java.util.List; |
| 18 | |
| 19 | import org.eclipse.linuxtools.tmf.core.statevalue.ITmfStateValue; |
| 20 | import org.eclipse.linuxtools.tmf.core.statevalue.StateValueTypeException; |
| 21 | import org.eclipse.linuxtools.tmf.core.statevalue.TmfStateValue; |
| 22 | |
| 23 | /** |
| 24 | * This is the base class for the StateHistorySystem. It contains all the |
| 25 | * current-state-updating methods. |
| 26 | * |
| 27 | * It's not abstract, as it can be used by itself: in this case, no History tree |
| 28 | * will be built underneath (no information will be saved to disk) and it will |
| 29 | * only be able to respond to queries to the current, latest time. |
| 30 | * |
| 31 | * @author alexmont |
| 32 | * |
| 33 | */ |
| 34 | public class StateSystem { |
| 35 | |
| 36 | /* References to the inner structures */ |
| 37 | protected AttributeTree attributeTree; |
| 38 | protected TransientState transState; |
| 39 | |
| 40 | /** |
| 41 | * Constructor. No configuration needed! |
| 42 | */ |
| 43 | public StateSystem() { |
| 44 | attributeTree = new AttributeTree(this); |
| 45 | |
| 46 | /* This will tell the builder to discard the intervals */ |
| 47 | transState = new TransientState(null); |
| 48 | } |
| 49 | |
| 50 | /** |
| 51 | * @name Quark-retrieving methods |
| 52 | */ |
| 53 | |
| 54 | /** |
| 55 | * Basic quark-retrieving method. Pass an attribute in parameter as an array |
| 56 | * of strings, the matching quark will be returned. |
| 57 | * |
| 58 | * This version will NOT create any new attributes. If an invalid attribute |
| 59 | * is requested, an exception will be thrown. This should ideally be used |
| 60 | * for doing read-only operations on the system, like queries for example. |
| 61 | * |
| 62 | * @param attribute |
| 63 | * Attribute given as its full path in the Attribute Tree |
| 64 | * @return The quark of the requested attribute, if it existed. |
| 65 | * @throws AttributeNotFoundException |
| 66 | * This exception is thrown if the requested attribute simply |
| 67 | * did not exist in the system. |
| 68 | */ |
| 69 | public int getQuarkAbsolute(String... attribute) |
| 70 | throws AttributeNotFoundException { |
| 71 | return attributeTree.getQuarkDontAdd(-1, attribute); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Basic quark-retrieving method. Pass an attribute in parameter as an array |
| 76 | * of strings, the matching quark will be returned. |
| 77 | * |
| 78 | * This version WILL create new attributes: if the attribute passed in |
| 79 | * parameter is new in the system, it will be added and its new quark will |
| 80 | * be returned. |
| 81 | * |
| 82 | * @param attribute |
| 83 | * Attribute given as its full path in the Attribute Tree |
| 84 | * @return The quark of the attribute (which either existed or just got |
| 85 | * created) |
| 86 | */ |
| 87 | public int getQuarkAbsoluteAndAdd(String... attribute) { |
| 88 | return attributeTree.getQuarkAndAdd(-1, attribute); |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * "Relative path" quark-getting method. Instead of specifying a full path, |
| 93 | * if you know the path is relative to another attribute for which you |
| 94 | * already have the quark, use this for better performance. |
| 95 | * |
| 96 | * This is useful for cases where a lot of modifications or queries will |
| 97 | * originate from the same branch of the attribute tree : the common part of |
| 98 | * the path won't have to be re-hashed for every access. |
| 99 | * |
| 100 | * This version will NOT create any new attributes. If an invalid attribute |
| 101 | * is requested, an exception will be thrown. This should ideally be used |
| 102 | * for doing read-only operations on the system, like queries for example. |
| 103 | * |
| 104 | * @param startingNodeQuark |
| 105 | * The quark of the attribute from which 'subPath' originates. |
| 106 | * @param subPath |
| 107 | * "Rest" of the path to get to the final attribute |
| 108 | * @return The matching quark, if it existed |
| 109 | * @throws AttributeNotFoundException |
| 110 | */ |
| 111 | public int getQuarkRelative(int startingNodeQuark, String... subPath) |
| 112 | throws AttributeNotFoundException { |
| 113 | return attributeTree.getQuarkDontAdd(startingNodeQuark, subPath); |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * "Relative path" quark-getting method. Instead of specifying a full path, |
| 118 | * if you know the path is relative to another attribute for which you |
| 119 | * already have the quark, use this for better performance. |
| 120 | * |
| 121 | * This is useful for cases where a lot of modifications or queries will |
| 122 | * originate from the same branch of the attribute tree : the common part of |
| 123 | * the path won't have to be re-hashed for every access. |
| 124 | * |
| 125 | * This version WILL create new attributes: if the attribute passed in |
| 126 | * parameter is new in the system, it will be added and its new quark will |
| 127 | * be returned. |
| 128 | * |
| 129 | * @param startingNodeQuark |
| 130 | * The quark of the attribute from which 'subPath' originates. |
| 131 | * @param subPath |
| 132 | * "Rest" of the path to get to the final attribute |
| 133 | * @return The matching quark, either if it's new of just got created. |
| 134 | */ |
| 135 | public int getQuarkRelativeAndAdd(int startingNodeQuark, String... subPath) { |
| 136 | return attributeTree.getQuarkAndAdd(startingNodeQuark, subPath); |
| 137 | } |
| 138 | |
| 139 | /** |
| 140 | * Return the sub-attributes of the target attribute, as a List of quarks. |
| 141 | * |
| 142 | * @param quark |
| 143 | * The attribute of which you want to sub-attributes. You can use |
| 144 | * "-1" here to specify the root node. |
| 145 | * @param recursive |
| 146 | * True if you want all recursive sub-attributes, false if you |
| 147 | * only want the first level. |
| 148 | * @return A List of integers, matching the quarks of the sub-attributes. |
| 149 | * @throws AttributeNotFoundException |
| 150 | * If the quark was not existing or invalid. |
| 151 | */ |
| 152 | public List<Integer> getSubAttributes(int quark, boolean recursive) |
| 153 | throws AttributeNotFoundException { |
| 154 | return attributeTree.getSubAttributes(quark, recursive); |
| 155 | } |
| 156 | |
| 157 | /** |
| 158 | * Batch quark-retrieving method. This method allows you to specify a path |
| 159 | * pattern which includes a wildcard "*" somewhere. It will check all the |
| 160 | * existing attributes in the attribute tree and return those who match the |
| 161 | * pattern. |
| 162 | * |
| 163 | * For example, passing ("Threads", "*", "Exec_mode") will return the list |
| 164 | * of quarks for attributes "Threads/1000/Exec_mode", |
| 165 | * "Threads/1500/Exec_mode", and so on, depending on what exists at this |
| 166 | * time in the attribute tree. |
| 167 | * |
| 168 | * If no wildcard is specified, the behavior is the same as |
| 169 | * getQuarkAbsolute() (except it will return a List with one entry). This |
| 170 | * method will never create new attributes. |
| 171 | * |
| 172 | * Only one wildcard "*" is supported at this time. |
| 173 | * |
| 174 | * @param pattern |
| 175 | * The array of strings representing the pattern to look for. It |
| 176 | * should ideally contain one entry that is only a "*". |
| 177 | * @return A List of attribute quarks, representing attributes that matched |
| 178 | * the pattern. If no attribute matched, the list will be empty (but |
| 179 | * not null). |
| 180 | */ |
| 181 | public List<Integer> getQuarks(String... pattern) { |
| 182 | List<Integer> quarks = new LinkedList<Integer>(); |
| 183 | List<String> prefix = new LinkedList<String>(); |
| 184 | List<String> suffix = new LinkedList<String>(); |
| 185 | boolean split = false; |
| 186 | String[] prefixStr; |
| 187 | String[] suffixStr; |
| 188 | List<Integer> directChildren; |
| 189 | int startingAttribute; |
| 190 | |
| 191 | /* Fill the "prefix" and "suffix" parts of the pattern around the '*' */ |
| 192 | for (String entry : pattern) { |
| 193 | if (entry.equals("*")) { //$NON-NLS-1$ |
| 194 | if (split) { |
| 195 | /* |
| 196 | * Split was already true? This means there was more than |
| 197 | * one wildcard. This is not supported, return an empty |
| 198 | * list. |
| 199 | */ |
| 200 | return quarks; |
| 201 | } |
| 202 | split = true; |
| 203 | continue; |
| 204 | } |
| 205 | |
| 206 | if (split) { |
| 207 | suffix.add(entry); |
| 208 | } else { |
| 209 | prefix.add(entry); |
| 210 | } |
| 211 | } |
| 212 | prefixStr = prefix.toArray(new String[prefix.size()]); |
| 213 | suffixStr = suffix.toArray(new String[suffix.size()]); |
| 214 | |
| 215 | /* |
| 216 | * If there was no wildcard, we'll only return the one matching |
| 217 | * attribute, if there is one. |
| 218 | */ |
| 219 | if (split == false) { |
| 220 | int quark; |
| 221 | try { |
| 222 | quark = getQuarkAbsolute(prefixStr); |
| 223 | } catch (AttributeNotFoundException e) { |
| 224 | /* It's fine, we'll just return the empty List */ |
| 225 | return quarks; |
| 226 | } |
| 227 | quarks.add(quark); |
| 228 | return quarks; |
| 229 | } |
| 230 | |
| 231 | try { |
| 232 | if (prefix.size() == 0) { |
| 233 | /* |
| 234 | * If 'prefix' is empty, this means the wildcard was the first |
| 235 | * element. Look for the root node's sub-attributes. |
| 236 | */ |
| 237 | startingAttribute = -1; |
| 238 | } else { |
| 239 | startingAttribute = getQuarkAbsolute(prefixStr); |
| 240 | } |
| 241 | directChildren = attributeTree.getSubAttributes(startingAttribute, |
| 242 | false); |
| 243 | } catch (AttributeNotFoundException e) { |
| 244 | /* That attribute path did not exist, return the empty array */ |
| 245 | return quarks; |
| 246 | } |
| 247 | |
| 248 | /* |
| 249 | * Iterate of all the sub-attributes, and only keep those who match the |
| 250 | * 'suffix' part of the initial pattern. |
| 251 | */ |
| 252 | for (int childQuark : directChildren) { |
| 253 | int matchingQuark; |
| 254 | try { |
| 255 | matchingQuark = getQuarkRelative(childQuark, suffixStr); |
| 256 | } catch (AttributeNotFoundException e) { |
| 257 | continue; |
| 258 | } |
| 259 | quarks.add(matchingQuark); |
| 260 | } |
| 261 | |
| 262 | return quarks; |
| 263 | } |
| 264 | |
| 265 | /** |
| 266 | * @name External methods related to insertions in the history - |
| 267 | */ |
| 268 | |
| 269 | /** |
| 270 | * Basic attribute modification method, we simply specify a new value, for a |
| 271 | * given attribute, effective at the given timestamp. |
| 272 | * |
| 273 | * @param t |
| 274 | * Timestamp of the state change |
| 275 | * @param value |
| 276 | * The State Value we want to assign to the attribute |
| 277 | * @param attributeQuark |
| 278 | * Integer value of the quark corresponding to the attribute we |
| 279 | * want to modify |
| 280 | * @throws TimeRangeException |
| 281 | * If the requested time is outside of the trace's range |
| 282 | * @throws AttributeNotFoundException |
| 283 | * If the requested attribute quark is invalid |
| 284 | * @throws StateValueTypeException |
| 285 | * If the inserted state value's type does not match what is |
| 286 | * already assigned to this attribute. |
| 287 | */ |
| 288 | public void modifyAttribute(long t, ITmfStateValue value, int attributeQuark) |
| 289 | throws TimeRangeException, AttributeNotFoundException, |
| 290 | StateValueTypeException { |
| 291 | transState.processStateChange(t, value, attributeQuark); |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | * Increment attribute method. Reads the current value of a given integer |
| 296 | * attribute (this value is right now in the Transient State), and increment |
| 297 | * it by 1. Useful for statistics. |
| 298 | * |
| 299 | * @param t |
| 300 | * Timestamp of the state change |
| 301 | * @param attributeQuark |
| 302 | * Attribute to increment. If it doesn't exist it will be added, |
| 303 | * with a new value of 1. |
| 304 | * @throws StateValueTypeException |
| 305 | * If the attribute already exists but is not of type Integer |
| 306 | * @throws TimeRangeException |
| 307 | * If the given timestamp is invalid |
| 308 | * @throws AttributeNotFoundException |
| 309 | * If the quark is invalid |
| 310 | */ |
| 311 | public void incrementAttribute(long t, int attributeQuark) |
| 312 | throws StateValueTypeException, TimeRangeException, |
| 313 | AttributeNotFoundException { |
| 314 | int prevValue = queryOngoingState(attributeQuark).unboxInt(); |
| 315 | /* prevValue should be == 0 if the attribute wasn't existing before */ |
| 316 | modifyAttribute(t, TmfStateValue.newValueInt(prevValue + 1), |
| 317 | attributeQuark); |
| 318 | } |
| 319 | |
| 320 | /** |
| 321 | * "Push" helper method. This uses the given integer attribute as a stack: |
| 322 | * The value of that attribute will represent the stack depth (always >= 1). |
| 323 | * Sub-attributes will be created, their base-name will be the position in |
| 324 | * the stack (1, 2, etc.) and their value will be the state value 'value' |
| 325 | * that was pushed to this position. |
| 326 | * |
| 327 | * @param t |
| 328 | * Timestamp of the state change |
| 329 | * @param value |
| 330 | * State value to assign to this stack position. |
| 331 | * @param attributeQuark |
| 332 | * The base attribute to use as a stack. If it does not exist if |
| 333 | * will be created (with depth = 1) |
| 334 | * @throws TimeRangeException |
| 335 | * If the requested timestamp is invalid |
| 336 | * @throws AttributeNotFoundException |
| 337 | * If the attribute is invalid |
| 338 | * @throws StateValueTypeException |
| 339 | * If the attribute 'attributeQuark' already exists, but is not |
| 340 | * of integer type. |
| 341 | */ |
| 342 | public void pushAttribute(long t, ITmfStateValue value, int attributeQuark) |
| 343 | throws TimeRangeException, AttributeNotFoundException, |
| 344 | StateValueTypeException { |
| 345 | Integer stackDepth = 0; |
| 346 | int subAttributeQuark; |
| 347 | ITmfStateValue previousSV = transState.getOngoingStateValue(attributeQuark); |
| 348 | |
| 349 | if (previousSV.isNull()) { |
| 350 | /* |
| 351 | * If the StateValue was null, this means this is the first time we |
| 352 | * use this attribute. Leave stackDepth at 0. |
| 353 | */ |
| 354 | } else if (previousSV.getType() == 0) { |
| 355 | /* Previous value was an integer, all is good, use it */ |
| 356 | stackDepth = previousSV.unboxInt(); |
| 357 | } else { |
| 358 | /* Previous state of this attribute was another type? Not good! */ |
| 359 | throw new StateValueTypeException(); |
| 360 | } |
| 361 | |
| 362 | if (stackDepth >= 10) { |
| 363 | /* |
| 364 | * Limit stackDepth to 10, to avoid having Attribute Trees grow out |
| 365 | * of control due to buggy insertions |
| 366 | */ |
| 367 | String message = "Stack limit reached, not pushing"; //$NON-NLS-1$ |
| 368 | throw new AttributeNotFoundException(message); |
| 369 | } |
| 370 | |
| 371 | stackDepth++; |
| 372 | subAttributeQuark = getQuarkRelativeAndAdd(attributeQuark, |
| 373 | stackDepth.toString()); |
| 374 | |
| 375 | modifyAttribute(t, TmfStateValue.newValueInt(stackDepth), |
| 376 | attributeQuark); |
| 377 | modifyAttribute(t, value, subAttributeQuark); |
| 378 | } |
| 379 | |
| 380 | /** |
| 381 | * Antagonist of the pushAttribute(), pops the top-most attribute on the |
| 382 | * stack-attribute. If this brings it back to depth = 0, the attribute is |
| 383 | * kept with depth = 0. If the value is already 0, or if the attribute |
| 384 | * doesn't exist, nothing is done. |
| 385 | * |
| 386 | * @param t |
| 387 | * Timestamp of the state change |
| 388 | * @param attributeQuark |
| 389 | * Quark of the stack-attribute to pop |
| 390 | * @throws AttributeNotFoundException |
| 391 | * If the attribute is invalid |
| 392 | * @throws TimeRangeException |
| 393 | * If the timestamp is invalid |
| 394 | * @throws StateValueTypeException |
| 395 | * If the target attribute already exists, but its state value |
| 396 | * type is invalid (not an integer) |
| 397 | */ |
| 398 | public void popAttribute(long t, int attributeQuark) |
| 399 | throws AttributeNotFoundException, TimeRangeException, |
| 400 | StateValueTypeException { |
| 401 | Integer stackDepth; |
| 402 | int subAttributeQuark; |
| 403 | ITmfStateValue previousSV = transState.getOngoingStateValue(attributeQuark); |
| 404 | |
| 405 | if (previousSV.isNull()) { |
| 406 | /* Same as if stackDepth == 0, see below */ |
| 407 | return; |
| 408 | } |
| 409 | if (previousSV.getType() != 0) { |
| 410 | /* |
| 411 | * The existing value was a string, this doesn't look like a valid |
| 412 | * stack attribute. |
| 413 | */ |
| 414 | throw new StateValueTypeException(); |
| 415 | } |
| 416 | |
| 417 | stackDepth = previousSV.unboxInt(); |
| 418 | |
| 419 | if (stackDepth == 0) { |
| 420 | /* |
| 421 | * Trying to pop an empty stack. This often happens at the start of |
| 422 | * traces, for example when we see a syscall_exit, without having |
| 423 | * the corresponding syscall_entry in the trace. Just ignore |
| 424 | * silently. |
| 425 | */ |
| 426 | return; |
| 427 | } |
| 428 | |
| 429 | if (stackDepth < 0) { |
| 430 | /* This on the other hand should not happen... */ |
| 431 | String message = "A top-level stack attribute " + //$NON-NLS-1$ |
| 432 | "cannot have a negative integer value."; //$NON-NLS-1$ |
| 433 | throw new StateValueTypeException(message); |
| 434 | } |
| 435 | |
| 436 | /* The attribute should already exist... */ |
| 437 | subAttributeQuark = getQuarkRelative(attributeQuark, |
| 438 | stackDepth.toString()); |
| 439 | |
| 440 | stackDepth--; |
| 441 | modifyAttribute(t, TmfStateValue.newValueInt(stackDepth), |
| 442 | attributeQuark); |
| 443 | removeAttribute(t, subAttributeQuark); |
| 444 | } |
| 445 | |
| 446 | /** |
| 447 | * Remove attribute method. Similar to the above modify- methods, with value |
| 448 | * = 0 / null, except we will also "nullify" all the sub-contents of the |
| 449 | * requested path (a bit like "rm -rf") |
| 450 | * |
| 451 | * @param t |
| 452 | * Timestamp of the state change |
| 453 | * @param attributeQuark |
| 454 | * Attribute to remove |
| 455 | * @throws TimeRangeException |
| 456 | * If the timestamp is invalid |
| 457 | * @throws AttributeNotFoundException |
| 458 | * If the quark is invalid |
| 459 | */ |
| 460 | public void removeAttribute(long t, int attributeQuark) |
| 461 | throws TimeRangeException, AttributeNotFoundException { |
| 462 | assert (attributeQuark >= 0); |
| 463 | List<Integer> childAttributes; |
| 464 | |
| 465 | /* |
| 466 | * "Nullify our children first, recursively. We pass 'false' because we |
| 467 | * handle the recursion ourselves. |
| 468 | */ |
| 469 | childAttributes = attributeTree.getSubAttributes(attributeQuark, false); |
| 470 | for (Integer childNodeQuark : childAttributes) { |
| 471 | assert (attributeQuark != childNodeQuark); |
| 472 | removeAttribute(t, childNodeQuark); |
| 473 | } |
| 474 | /* Nullify ourselves */ |
| 475 | try { |
| 476 | transState.processStateChange(t, TmfStateValue.nullValue(), |
| 477 | attributeQuark); |
| 478 | } catch (StateValueTypeException e) { |
| 479 | /* |
| 480 | * Will not happen since we're inserting null values only, but |
| 481 | * poor compiler has no way of knowing this... |
| 482 | */ |
| 483 | e.printStackTrace(); |
| 484 | } |
| 485 | } |
| 486 | |
| 487 | /** |
| 488 | * @name "Current" query/update methods - |
| 489 | */ |
| 490 | |
| 491 | /** |
| 492 | * Returns the current state value we have (in the Transient State) for the |
| 493 | * given attribute. |
| 494 | * |
| 495 | * This is useful even for a StateHistorySystem, as we are guaranteed it |
| 496 | * will only do a memory access and not go look on disk (and we don't even |
| 497 | * have to provide a timestamp!) |
| 498 | * |
| 499 | * @param attributeQuark |
| 500 | * For which attribute we want the current state |
| 501 | * @return The State value that's "current" for this attribute |
| 502 | * @throws AttributeNotFoundException |
| 503 | * If the requested attribute is invalid |
| 504 | */ |
| 505 | public ITmfStateValue queryOngoingState(int attributeQuark) |
| 506 | throws AttributeNotFoundException { |
| 507 | return transState.getOngoingStateValue(attributeQuark); |
| 508 | } |
| 509 | |
| 510 | /** |
| 511 | * Modify a current "ongoing" state (instead of inserting a state change, |
| 512 | * like modifyAttribute() and others). |
| 513 | * |
| 514 | * This can be used to update the value of a previous state change, for |
| 515 | * example when we get information at the end of the state and not at the |
| 516 | * beginning. (return values of system calls, etc.) |
| 517 | * |
| 518 | * Note that past states can only be modified while they are still in |
| 519 | * memory, so only the "current state" can be updated. Once they get |
| 520 | * committed to disk (by inserting a new state change) it becomes too late. |
| 521 | * |
| 522 | * @param newValue |
| 523 | * The new value that will overwrite the "current" one. |
| 524 | * @param attributeQuark |
| 525 | * For which attribute in the system |
| 526 | * @throws AttributeNotFoundException |
| 527 | * If the requested attribute is invalid |
| 528 | */ |
| 529 | public void updateOngoingState(ITmfStateValue newValue, int attributeQuark) |
| 530 | throws AttributeNotFoundException { |
| 531 | transState.changeOngoingStateValue(attributeQuark, newValue); |
| 532 | } |
| 533 | |
| 534 | /** |
| 535 | * @name Debugging methods |
| 536 | */ |
| 537 | |
| 538 | /** |
| 539 | * This returns the slash-separated path of an attribute by providing its |
| 540 | * quark |
| 541 | * |
| 542 | * @param attributeQuark |
| 543 | * The quark of the attribute we want |
| 544 | * @return One single string separated with '/', like a filesystem path |
| 545 | */ |
| 546 | public String getFullAttributePath(int attributeQuark) { |
| 547 | return attributeTree.getFullAttributeName(attributeQuark); |
| 548 | } |
| 549 | |
| 550 | /** |
| 551 | * Print out the contents of the inner structures. |
| 552 | * |
| 553 | * @param writer |
| 554 | * The PrintWriter in which to print the output |
| 555 | */ |
| 556 | public void debugPrint(PrintWriter writer) { |
| 557 | attributeTree.debugPrint(writer); |
| 558 | transState.debugPrint(writer); |
| 559 | } |
| 560 | |
| 561 | } |