inc/classes/main/stacker/file/class_BaseFileStack.php

   1 <?php
   2 /**
   3  * A general file-based stack class
   4  *
   5  * @author              Roland Haeder <webmaster@ship-simu.org>
   6  * @version             0.0.0
   7  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2013 Core Developer Team
   8  * @license             GNU GPL 3.0 or any newer version
   9  * @link                http://www.ship-simu.org
  10  *
  11  * This program is free software: you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation, either version 3 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  */
  24 class BaseFileStack extends BaseStacker {
  25         /**
  26          * Magic for this stack
  27          */
  28         const STACK_MAGIC = 'STACKv0.1';
  29
  30         /**
  31          * Separator for header data
  32          */
  33         const SEPARATOR_HEADER_DATA = 0x01;
  34
  35         /**
  36          * Separator header->entries
  37          */
  38         const SEPARATOR_HEADER_ENTRIES = 0x02;
  39
  40         /**
  41          * Separator hash->name
  42          */
  43         const SEPARATOR_HASH_NAME = 0x03;
  44
  45         /**
  46          * Length of name
  47          */
  48         const LENGTH_NAME = 10;
  49
  50         /**
  51          * Length of count
  52          */
  53         const LENGTH_COUNT = 20;
  54
  55         /**
  56          * Length of position
  57          */
  58         const LENGTH_POSITION = 20;
  59
  60         /**
  61          * Counter for total entries
  62          */
  63         private $totalEntries = 0;
  64
  65         /**
  66          * Current seek position
  67          */
  68         private $seekPosition = 0;
  69
  70         /**
  71          * Size of header
  72          */
  73         private $headerSize = 0;
  74
  75         /**
  76          * File header
  77          */
  78         private $header = array();
  79
  80         /**
  81          * Protected constructor
  82          *
  83          * @param       $className      Name of the class
  84          * @return      void
  85          */
  86         protected function __construct ($className) {
  87                 // Call parent constructor
  88                 parent::__construct($className);
  89
  90                 // Calculate header size
  91                 $this->headerSize = (
  92                         strlen(self::STACK_MAGIC) +
  93                         strlen(self::SEPARATOR_HEADER_DATA) +
  94                         self::LENGTH_COUNT +
  95                         strlen(self::SEPARATOR_HEADER_DATA) +
  96                         self::LENGTH_POSITION +
  97                         strlen(self::SEPARATOR_HEADER_ENTRIES)
  98                 );
  99         }
 100
 101         /**
 102          * Getter for total entries
 103          *
 104          * @return      $totalEntries   Total entries in this stack
 105          */
 106         private function getCounter () {
 107                 // Get it
 108                 return $this->totalEntries;
 109         }
 110
 111         /**
 112          * Increment counter
 113          *
 114          * @return      void
 115          */
 116         private function incrementCounter () {
 117                 // Get it
 118                 $this->totalEntries++;
 119         }
 120
 121         /**
 122          * Getter for seek position
 123          *
 124          * @return      $seekPosition   Current seek position (stored here in object)
 125          */
 126         private function getSeekPosition () {
 127                 // Get it
 128                 return $this->seekPosition;
 129         }
 130
 131         /**
 132          * Setter for seek position
 133          *
 134          * @param       $seekPosition   Current seek position (stored here in object)
 135          * @return      void
 136          */
 137         private function setSeekPosition ($seekPosition) {
 138                 // And set it
 139                 $this->seekPosition = $seekPosition;
 140         }
 141
 142         /**
 143          * Updates seekPosition attribute from file to avoid to much access on file.
 144          *
 145          * @return      void
 146          */
 147         private function updateSeekPosition () {
 148                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 149
 150                 // Get key (= seek position)
 151                 $seekPosition = $this->getIteratorInstance()->key();
 152                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Setting seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
 153
 154                 // And set it here
 155                 $this->setSeekPosition($seekPosition);
 156
 157                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 158         }
 159
 160         /**
 161          * Reads the file header
 162          *
 163          * @return      void
 164          */
 165         private function readFileHeader () {
 166                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 167
 168                 // First rewind to beginning as the header sits at the beginning ...
 169                 $this->getIteratorInstance()->rewind();
 170
 171                 // Then read it (see constructor for calculation)
 172                 $data = $this->getIteratorInstance()->read($this->headerSize);
 173                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->headerSize));
 174
 175                 // Have all requested bytes been read?
 176                 assert(strlen($data) == $this->headerSize);
 177                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 178
 179                 // Last character must be the separator
 180                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
 181                 assert(substr($data, -1, 1) == chr(self::SEPARATOR_HEADER_ENTRIES));
 182                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 183
 184                 // Okay, then remove it
 185                 $data = substr($data, 0, -1);
 186
 187                 // And update seek position
 188                 $this->updateSeekPosition();
 189
 190                 /*
 191                  * Now split it:
 192                  *
 193                  * 0 => Magic
 194                  * 1 => Total entries
 195                  * 2 => Current seek position
 196                  */
 197                 $this->header = explode(chr(self::SEPARATOR_HEADER_DATA), $data);
 198
 199                 // Check if the array has only 3 elements
 200                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($this->header), print_r($this->header, TRUE)));
 201                 assert(count($this->header) == 3);
 202                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 203
 204                 // Check magic
 205                 assert($this->header[0] == self::STACK_MAGIC);
 206                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 207
 208                 // Check length of count and seek position
 209                 assert(strlen($this->header[1]) == self::LENGTH_COUNT);
 210                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 211                 assert(strlen($this->header[2]) == self::LENGTH_POSITION);
 212                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 213
 214                 // Decode count and seek position
 215                 $this->header[1] = hex2bin($this->header[1]);
 216                 $this->header[2] = hex2bin($this->header[2]);
 217
 218                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 219         }
 220
 221         /**
 222          * Checks whether the file header is initialized
 223          *
 224          * @return      $isInitialized  Whether the file header is initialized
 225          */
 226         private function isFileHeaderInitialized () {
 227                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 228                 // Default is not initialized
 229                 $isInitialized = FALSE;
 230
 231                 // Is the file initialized?
 232                 if ($this->isFileInitialized()) {
 233                         // Some bytes has been written, so rewind to start of it.
 234                         $rewindStatus = $this->getIteratorInstance()->rewind();
 235                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] rewindStatus=%s', __METHOD__, __LINE__, $rewindStatus));
 236
 237                         // Is the rewind() call successfull?
 238                         if ($rewindStatus != 1) {
 239                                 // Something bad happened
 240                                 self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Could not rewind().', __METHOD__, __LINE__));
 241                         } // END - if
 242
 243                         // Read file header
 244                         $this->readFileHeader();
 245
 246                         // The above method does already check the header
 247                         $isInitialized = TRUE;
 248                 } // END - if
 249
 250                 // Return result
 251                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
 252                 return $isInitialized;
 253         }
 254
 255         /**
 256          * Checks whether the file-based stack has been initialized
 257          *
 258          * @return      $isInitialized          Whether the file's size is zero
 259          */
 260         private function isFileInitialized () {
 261                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 262
 263                 // Get it from iterator which holds the pointer instance. If FALSE is returned
 264                 $fileSize = $this->getIteratorInstance()->size();
 265                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] fileSize=%s', __METHOD__, __LINE__, $fileSize));
 266
 267                 /*
 268                  * The returned file size should not be FALSE or NULL as this means
 269                  * that the pointer class does not work correctly.
 270                  */
 271                 assert(is_int($fileSize));
 272
 273                 // Is more than 0 returned?
 274                 $isInitialized = ($fileSize > 0);
 275
 276                 // Return result
 277                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
 278                 return $isInitialized;
 279         }
 280
 281         /**
 282          * Creates the file-stack's header
 283          *
 284          * @return      void
 285          */
 286         private function createFileHeader () {
 287                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 288                 // The file's header should not be initialized here
 289                 assert(!$this->isFileHeaderInitialized());
 290
 291                 // Simple flush file header which will create it.
 292                 $this->flushFileHeader();
 293
 294                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!!', __METHOD__, __LINE__));
 295         }
 296
 297         /**
 298          * Flushes the file header
 299          *
 300          * @return      void
 301          */
 302         private function flushFileHeader () {
 303                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 304
 305                 // Put all informations together
 306                 $header = sprintf('%s%s%s%s%s%s',
 307                         // Magic
 308                         self::STACK_MAGIC,
 309
 310                         // Separator magic<->count
 311                         chr(self::SEPARATOR_HEADER_DATA),
 312
 313                         // Total entries (will be zero) and pad it to 20 chars
 314                         str_pad($this->dec2hex($this->getCounter()), self::LENGTH_COUNT, '0', STR_PAD_LEFT),
 315
 316                         // Separator count<->seek position
 317                         chr(self::SEPARATOR_HEADER_DATA),
 318
 319                         // Position (will be zero)
 320                         str_pad($this->dec2hex($this->getSeekPosition(), 2), self::LENGTH_POSITION, '0', STR_PAD_LEFT),
 321
 322                         // Separator position<->entries
 323                         chr(self::SEPARATOR_HEADER_ENTRIES)
 324                 );
 325
 326                 // Write it to disk (header is always at seek position 0)
 327                 $this->writeData(0, $header);
 328
 329                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 330         }
 331
 332         /**
 333          * Writes data at given position
 334          *
 335          * @param       $seekPosition   Seek position
 336          * @param       $data                   Data to be written
 337          * @return      void
 338          */
 339         private function writeData ($seekPosition, $data) {
 340                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data()=%s - CALLED!', __METHOD__, __LINE__, $seekPosition, strlen($data)));
 341
 342                 // Write data at given position
 343                 $this->getIteratorInstance()->writeAtPosition($seekPosition, $data);
 344
 345                 // Update seek position
 346                 $this->updateSeekPosition();
 347
 348                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 349         }
 350
 351         /**
 352          * Pre-allocates file (if enabled) with some space for later faster write access.
 353          *
 354          * @return      void
 355          */
 356         private function preAllocateFile () {
 357                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 358
 359                 // Is it enabled?
 360                 if ($this->getConfigInstance()->getConfigEntry('file_stack_pre_allocate_enabled') != 'Y') {
 361                         // Not enabled
 362                         self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Not pre-allocating stack file.', __METHOD__, __LINE__));
 363
 364                         // Don't continue here.
 365                         return;
 366                 } // END - if
 367
 368                 // Message to user
 369                 self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Pre-allocating stack file ...', __METHOD__, __LINE__));
 370
 371                 /*
 372                  * Calculate minimum length for one entry:
 373                  * minimum length = hash length + separator + name + minimum entry size = ?? + 1 + 10 + 1 = ??
 374                  */
 375                 $minLengthEntry = self::getHashLength() + strlen(self::SEPARATOR_HASH_NAME) + self::LENGTH_NAME + 1;
 376                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] minLengthEntry=%s', __METHOD__, __LINE__, $minLengthEntry));
 377
 378                 // Calulcate seek position
 379                 $seekPosition = $minLengthEntry * $this->getConfigInstance()->getConfigEntry('file_stack_pre_allocate_count');
 380                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
 381
 382                 // Now simply write a NUL there. This will pre-allocate the file.
 383                 $this->writeData($seekPosition, chr(0));
 384
 385                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 386         }
 387
 388         /**
 389          * Initializes this file-based stack.
 390          *
 391          * @param       $fileName       File name of this stack
 392          * @return      void
 393          */
 394         protected function initFileStack ($fileName) {
 395                 // Get a file i/o pointer instance
 396                 $pointerInstance = ObjectFactory::createObjectByConfiguredName('file_raw_input_output_class', array($fileName));
 397
 398                 // Get iterator instance
 399                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_io_iterator_class', array($pointerInstance));
 400
 401                 // Is the instance implementing the right interface?
 402                 assert($iteratorInstance instanceof SeekableWritableFileIterator);
 403
 404                 // Set iterator here
 405                 $this->setIteratorInstance($iteratorInstance);
 406
 407                 // Is the file's header initialized?
 408                 if ($this->isFileHeaderInitialized()) {
 409                         // Then load it
 410                         $this->loadFileHeader();
 411                 } else {
 412                         // No, then create it (which may pre-allocate the stack)
 413                         $this->createFileHeader();
 414
 415                         // And pre-allocate a bit
 416                         $this->preAllocateFile();
 417                 }
 418         }
 419
 420         /**
 421          * Initializes given stacker
 422          *
 423          * @param       $stackerName    Name of the stack
 424          * @param       $forceReInit    Force re-initialization
 425          * @return      void
 426          * @throws      AlreadyInitializedStackerException      If the stack is already initialized
 427          */
 428         public function initStack ($stackerName, $forceReInit = FALSE) {
 429                 // Is the stack already initialized?
 430                 if (($forceReInit === FALSE) && ($this->isStackInitialized($stackerName))) {
 431                         // Then throw the exception
 432                         throw new AlreadyInitializedStackerException(array($this, $stackerName, $forceReInit), self::EXCEPTION_STACKER_ALREADY_INITIALIZED);
 433                 } // END - if
 434
 435                 // Initialize the given stack
 436                 $this->partialStub('stackerName=' . $stackerName . ',forceReInit=' . intval($forceReInit));
 437         }
 438
 439         /**
 440          * Checks whether the given stack is initialized (set in array $stackers)
 441          *
 442          * @param       $stackerName    Name of the stack
 443          * @return      $isInitialized  Whether the stack is initialized
 444          */
 445         public function isStackInitialized ($stackerName) {
 446                 // Is is there?
 447                 $this->partialStub('stackerName=' . $stackerName);
 448                 $isInitialized = TRUE;
 449
 450                 // Return result
 451                 return $isInitialized;
 452         }
 453
 454         /**
 455          * Getter for size of given stack (array count)
 456          *
 457          * @param       $stackerName    Name of the stack
 458          * @return      $count                  Size of stack (array count)
 459          * @throws      NoStackerException      If given stack is missing
 460          */
 461         public function getStackCount ($stackerName) {
 462                 // Is the stack not yet initialized?
 463                 if (!$this->isStackInitialized($stackerName)) {
 464                         // Throw an exception
 465                         throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
 466                 } // END - if
 467
 468                 // Now, count the array of entries
 469                 $this->partialStub('stackerName=' . $stackerName);
 470                 $count = 0;
 471
 472                 // Return result
 473                 return $count;
 474         }
 475
 476         /**
 477          * Adds a value to given stack
 478          *
 479          * @param       $stackerName    Name of the stack
 480          * @param       $value                  Value to add to this stacker
 481          * @return      void
 482          * @throws      FullStackerException    Thrown if the stack is full
 483          */
 484         protected function addValue ($stackerName, $value) {
 485                 // Is the stack not yet initialized or full?
 486                 if (!$this->isStackInitialized($stackerName)) {
 487                         // Then do it here
 488                         $this->initStack($stackerName);
 489                 } elseif ($this->isStackFull($stackerName)) {
 490                         // Stacker is full
 491                         throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
 492                 }
 493
 494                 // Now add the value to the stack
 495                 $this->partialStub('stackerName=' . $stackerName . ',value[]=' . gettype($value));
 496         }
 497
 498         /**
 499          * Get last value from named stacker
 500          *
 501          * @param       $stackerName    Name of the stack
 502          * @return      $value                  Value of last added value
 503          * @throws      NoStackerException      If the named stacker was not found
 504          * @throws      EmptyStackerException   If the named stacker is empty
 505          */
 506         protected function getLastValue ($stackerName) {
 507                 // Is the stack not yet initialized or full?
 508                 if (!$this->isStackInitialized($stackerName)) {
 509                         // Throw an exception
 510                         throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
 511                 } elseif ($this->isStackEmpty($stackerName)) {
 512                         // Throw an exception
 513                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 514                 }
 515
 516                 // Now get the last value
 517                 $this->partialStub('stackerName=' . $stackerName);
 518                 $value = NULL;
 519
 520                 // Return it
 521                 return $value;
 522         }
 523
 524         /**
 525          * Get first value from named stacker
 526          *
 527          * @param       $stackerName    Name of the stack
 528          * @return      $value                  Value of last added value
 529          * @throws      NoStackerException      If the named stacker was not found
 530          * @throws      EmptyStackerException   If the named stacker is empty
 531          */
 532         protected function getFirstValue ($stackerName) {
 533                 // Is the stack not yet initialized or full?
 534                 if (!$this->isStackInitialized($stackerName)) {
 535                         // Throw an exception
 536                         throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
 537                 } elseif ($this->isStackEmpty($stackerName)) {
 538                         // Throw an exception
 539                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 540                 }
 541
 542                 // Now get the first value
 543                 $this->partialStub('stackerName=' . $stackerName);
 544                 $value = NULL;
 545
 546                 // Return it
 547                 return $value;
 548         }
 549
 550         /**
 551          * "Pops" last entry from stack
 552          *
 553          * @param       $stackerName    Name of the stack
 554          * @return      $value                  Value "poped" from array
 555          * @throws      NoStackerException      If the named stacker was not found
 556          * @throws      EmptyStackerException   If the named stacker is empty
 557          */
 558         protected function popLast ($stackerName) {
 559                 // Is the stack not yet initialized or full?
 560                 if (!$this->isStackInitialized($stackerName)) {
 561                         // Throw an exception
 562                         throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
 563                 } elseif ($this->isStackEmpty($stackerName)) {
 564                         // Throw an exception
 565                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 566                 }
 567
 568                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 569                 $this->partialStub('stackerName=' . $stackerName);
 570                 return NULL;
 571         }
 572
 573         /**
 574          * "Pops" first entry from stack
 575          *
 576          * @param       $stackerName    Name of the stack
 577          * @return      $value                  Value "shifted" from array
 578          * @throws      NoStackerException      If the named stacker was not found
 579          * @throws      EmptyStackerException   If the named stacker is empty
 580          */
 581         protected function popFirst ($stackerName) {
 582                 // Is the stack not yet initialized or full?
 583                 if (!$this->isStackInitialized($stackerName)) {
 584                         // Throw an exception
 585                         throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
 586                 } elseif ($this->isStackEmpty($stackerName)) {
 587                         // Throw an exception
 588                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 589                 }
 590
 591                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 592                 $this->partialStub('stackerName=' . $stackerName);
 593                 return NULL;
 594         }
 595 }
 596
 597 // [EOF]
 598 ?>