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

   1 <?php
   2 // Own namespace
   3 namespace CoreFramework\Stacker\Filesystem;
   4
   5 // Import framework stuff
   6 use CoreFramework\Factory\ObjectFactory;
   7 use CoreFramework\Filesystem\File\BaseBinaryFile;
   8 use CoreFramework\Generic\UnsupportedOperationException;
   9 use CoreFramework\Iterator\Filesystem\SeekableWritableFileIterator;
  10 use CoreFramework\Stacker\BaseStacker;
  11
  12 /**
  13  * A general file-based stack class
  14  *
  15  * @author              Roland Haeder <webmaster@ship-simu.org>
  16  * @version             0.0.0
  17  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  18  * @license             GNU GPL 3.0 or any newer version
  19  * @link                http://www.ship-simu.org
  20  *
  21  * This program is free software: you can redistribute it and/or modify
  22  * it under the terms of the GNU General Public License as published by
  23  * the Free Software Foundation, either version 3 of the License, or
  24  * (at your option) any later version.
  25  *
  26  * This program is distributed in the hope that it will be useful,
  27  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  29  * GNU General Public License for more details.
  30  *
  31  * You should have received a copy of the GNU General Public License
  32  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  33  */
  34 class BaseFileStack extends BaseStacker {
  35         /**
  36          * Magic for this stack
  37          */
  38         const STACK_MAGIC = 'STACKv0.1';
  39
  40         /**
  41          * Name of array index for gap position
  42          */
  43         const ARRAY_INDEX_GAP_POSITION = 'gap';
  44
  45         /**
  46          * Name of array index for hash
  47          */
  48         const ARRAY_INDEX_HASH = 'hash';
  49
  50         /**
  51          * Name of array index for length of raw data
  52          */
  53         const ARRAY_INDEX_DATA_LENGTH = 'length';
  54
  55         /**
  56          * Protected constructor
  57          *
  58          * @param       $className      Name of the class
  59          * @return      void
  60          */
  61         protected function __construct ($className) {
  62                 // Call parent constructor
  63                 parent::__construct($className);
  64         }
  65
  66         /**
  67          * Reads the file header
  68          *
  69          * @return      void
  70          * @todo        To hard assertions here, better rewrite them to exceptions
  71          */
  72         public function readFileHeader () {
  73                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
  74
  75                 // First rewind to beginning as the header sits at the beginning ...
  76                 $this->getIteratorInstance()->rewind();
  77
  78                 // Then read it (see constructor for calculation)
  79                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
  80                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->getIteratorInstance()->getHeaderSize()));
  81
  82                 // Have all requested bytes been read?
  83                 assert(strlen($data) == $this->getIteratorInstance()->getHeaderSize());
  84                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  85
  86                 // Last character must be the separator
  87                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
  88                 assert(substr($data, -1, 1) == chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES));
  89                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  90
  91                 // Okay, then remove it
  92                 $data = substr($data, 0, -1);
  93
  94                 // And update seek position
  95                 $this->getIteratorInstance()->updateSeekPosition();
  96
  97                 /*
  98                  * Now split it:
  99                  *
 100                  * 0 => magic
 101                  * 1 => total entries
 102                  * 2 => current seek position
 103                  */
 104                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
 105
 106                 // Set header here
 107                 $this->getIteratorInstance()->setHeader($header);
 108
 109                 // Check if the array has only 3 elements
 110                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($header), print_r($header, true)));
 111                 assert(count($header) == 3);
 112                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 113
 114                 // Check magic
 115                 assert($header[0] == self::STACK_MAGIC);
 116                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 117
 118                 // Check length of count and seek position
 119                 assert(strlen($header[1]) == BaseBinaryFile::LENGTH_COUNT);
 120                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 121                 assert(strlen($header[2]) == BaseBinaryFile::LENGTH_POSITION);
 122                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 123
 124                 // Decode count and seek position
 125                 $header[1] = hex2bin($header[1]);
 126                 $header[2] = hex2bin($header[2]);
 127
 128                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 129         }
 130
 131         /**
 132          * Flushes the file header
 133          *
 134          * @return      void
 135          */
 136         public function flushFileHeader () {
 137                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 138
 139                 // Put all informations together
 140                 $header = sprintf('%s%s%s%s%s%s',
 141                         // Magic
 142                         self::STACK_MAGIC,
 143
 144                         // Separator magic<->count
 145                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 146
 147                         // Total entries (will be zero) and pad it to 20 chars
 148                         str_pad($this->dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 149
 150                         // Separator count<->seek position
 151                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 152
 153                         // Position (will be zero)
 154                         str_pad($this->dec2hex($this->getIteratorInstance()->getSeekPosition(), 2), BaseBinaryFile::LENGTH_POSITION, '0', STR_PAD_LEFT),
 155
 156                         // Separator position<->entries
 157                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 158                 );
 159
 160                 // Write it to disk (header is always at seek position 0)
 161                 $this->getIteratorInstance()->writeData(0, $header, false);
 162
 163                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 164         }
 165
 166         /**
 167          * Initializes this file-based stack.
 168          *
 169          * @param       $fileName       File name of this stack
 170          * @param       $type           Type of this stack (e.g. url_source for URL sources)
 171          * @return      void
 172          * @todo        Currently the stack file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole stack file.
 173          */
 174         protected function initFileStack ($fileName, $type) {
 175                 // Get a stack file instance
 176                 $fileInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileName, $this));
 177
 178                 // Get iterator instance
 179                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 180
 181                 // Is the instance implementing the right interface?
 182                 assert($iteratorInstance instanceof SeekableWritableFileIterator);
 183
 184                 // Set iterator here
 185                 $this->setIteratorInstance($iteratorInstance);
 186
 187                 // Calculate header size
 188                 $this->getIteratorInstance()->setHeaderSize(
 189                         strlen(self::STACK_MAGIC) +
 190                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 191                         BaseBinaryFile::LENGTH_COUNT +
 192                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 193                         BaseBinaryFile::LENGTH_POSITION +
 194                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 195                 );
 196
 197                 // Init counters and gaps array
 198                 $this->getIteratorInstance()->initCountersGapsArray();
 199
 200                 // Is the file's header initialized?
 201                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 202                         // No, then create it (which may pre-allocate the stack)
 203                         $this->getIteratorInstance()->createFileHeader();
 204
 205                         // And pre-allocate a bit
 206                         $this->getIteratorInstance()->preAllocateFile('file_stack');
 207                 } // END - if
 208
 209                 // Load the file header
 210                 $this->readFileHeader();
 211
 212                 // Count all entries in file
 213                 $this->getIteratorInstance()->analyzeFile();
 214
 215                 /*
 216                  * Get stack index instance. This can be used for faster
 217                  * "defragmentation" and startup.
 218                  */
 219                 $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileName, $type);
 220
 221                 // And set it here
 222                 $this->setIndexInstance($indexInstance);
 223         }
 224
 225         /**
 226          * Adds a value to given stack
 227          *
 228          * @param       $stackerName    Name of the stack
 229          * @param       $value                  Value to add to this stacker
 230          * @return      void
 231          * @throws      FullStackerException    If the stack is full
 232          */
 233         protected function addValue ($stackerName, $value) {
 234                 // Do some tests
 235                 if ($this->isStackFull($stackerName)) {
 236                         // Stacker is full
 237                         throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
 238                 } // END - if
 239
 240                 // Debug message
 241                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName . ',value[' . gettype($value) . ']=' . print_r($value, true));
 242
 243                 // No objects/resources are allowed as their serialization takes to long
 244                 assert(!is_object($value));
 245                 assert(!is_resource($value));
 246
 247                 /*
 248                  * Now add the value to the file stack which returns gap position, a
 249                  * hash and length of the raw data.
 250                  */
 251                 $data = $this->getIteratorInstance()->writeValueToFile($stackerName, $value);
 252
 253                 // Add the hash and gap position to the index
 254                 $this->getIndexInstance()->addHashToIndex($stackerName, $data);
 255         }
 256
 257         /**
 258          * Get last value from named stacker
 259          *
 260          * @param       $stackerName    Name of the stack
 261          * @return      $value                  Value of last added value
 262          * @throws      EmptyStackerException   If the stack is empty
 263          */
 264         protected function getLastValue ($stackerName) {
 265                 // Is the stack not yet initialized or full?
 266                 if ($this->isStackEmpty($stackerName)) {
 267                         // Throw an exception
 268                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 269                 } // END - if
 270
 271                 // Now get the last value
 272                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 273                 $value = NULL;
 274
 275                 // Return it
 276                 return $value;
 277         }
 278
 279         /**
 280          * Get first value from named stacker
 281          *
 282          * @param       $stackerName    Name of the stack
 283          * @return      $value                  Value of last added value
 284          * @throws      EmptyStackerException   If the stack is empty
 285          */
 286         protected function getFirstValue ($stackerName) {
 287                 // Is the stack not yet initialized or full?
 288                 if ($this->isStackEmpty($stackerName)) {
 289                         // Throw an exception
 290                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 291                 } // END - if
 292
 293                 // Now get the first value
 294                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 295                 $value = NULL;
 296
 297                 // Return it
 298                 return $value;
 299         }
 300
 301         /**
 302          * "Pops" last entry from stack
 303          *
 304          * @param       $stackerName    Name of the stack
 305          * @return      $value                  Value "poped" from array
 306          * @throws      EmptyStackerException   If the stack is empty
 307          */
 308         protected function popLast ($stackerName) {
 309                 // Is the stack not yet initialized or full?
 310                 if ($this->isStackEmpty($stackerName)) {
 311                         // Throw an exception
 312                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 313                 } // END - if
 314
 315                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 316                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 317                 return NULL;
 318         }
 319
 320         /**
 321          * "Pops" first entry from stack
 322          *
 323          * @param       $stackerName    Name of the stack
 324          * @return      $value                  Value "shifted" from array
 325          * @throws      EmptyStackerException   If the named stacker is empty
 326          */
 327         protected function popFirst ($stackerName) {
 328                 // Is the stack not yet initialized or full?
 329                 if ($this->isStackEmpty($stackerName)) {
 330                         // Throw an exception
 331                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 332                 } // END - if
 333
 334                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 335                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 336                 return NULL;
 337         }
 338
 339         /**
 340          * Checks whether the given stack is full
 341          *
 342          * @param       $stackerName    Name of the stack
 343          * @return      $isFull                 Whether the stack is full
 344          */
 345         protected function isStackFull ($stackerName) {
 346                 // File-based stacks will only run full if the disk space is low.
 347                 // @TODO Please implement this, returning false
 348                 $isFull = false;
 349
 350                 // Return result
 351                 return $isFull;
 352         }
 353
 354         /**
 355          * Checks whether the given stack is empty
 356          *
 357          * @param       $stackerName            Name of the stack
 358          * @return      $isEmpty                        Whether the stack is empty
 359          * @throws      NoStackerException      If given stack is missing
 360          */
 361         public function isStackEmpty ($stackerName) {
 362                 // So, is the stack empty?
 363                 $isEmpty = (($this->getStackCount($stackerName)) == 0);
 364
 365                 // Return result
 366                 return $isEmpty;
 367         }
 368
 369         /**
 370          * Initializes given stacker
 371          *
 372          * @param       $stackerName    Name of the stack
 373          * @param       $forceReInit    Force re-initialization
 374          * @return      void
 375          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 376          */
 377         public function initStack ($stackerName, $forceReInit = false) {
 378                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 379         }
 380
 381         /**
 382          * Initializes all stacks
 383          *
 384          * @return      void
 385          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 386          */
 387         public function initStacks (array $stacks, $forceReInit = false) {
 388                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 389         }
 390
 391         /**
 392          * Checks whether the given stack is initialized (set in array $stackers)
 393          *
 394          * @param       $stackerName    Name of the stack
 395          * @return      $isInitialized  Whether the stack is initialized
 396          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 397          */
 398         public function isStackInitialized ($stackerName) {
 399                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 400         }
 401
 402         /**
 403          * Determines whether the EOF has been reached
 404          *
 405          * @return      $isEndOfFileReached             Whether the EOF has been reached
 406          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 407          */
 408         public function isEndOfFileReached () {
 409                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 410         }
 411
 412         /**
 413          * Getter for file name
 414          *
 415          * @return      $fileName       The current file name
 416          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 417          */
 418         public function getFileName () {
 419                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 420         }
 421
 422         /**
 423          * Getter for size of given stack (array count)
 424          *
 425          * @param       $stackerName    Name of the stack
 426          * @return      $count                  Size of stack (array count)
 427          */
 428         public function getStackCount ($stackerName) {
 429                 // Now, simply return the found count value, this must be up-to-date then!
 430                 return $this->getIteratorInstance()->getCounter();
 431         }
 432
 433         /**
 434          * Calculates minimum length for one entry/block
 435          *
 436          * @return      $length         Minimum length for one entry/block
 437          */
 438         public function calculateMinimumBlockLength () {
 439                 // Calulcate it
 440                 $length =
 441                         // Length of entry group
 442                         BaseBinaryFile::LENGTH_GROUP + strlen(chr(BaseBinaryFile::SEPARATOR_GROUP_HASH)) +
 443                         // Hash + value
 444                         self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
 445                         // Final separator
 446                         strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 447
 448                 // Return it
 449                 return $length;
 450         }
 451
 452         /**
 453          * Initializes counter for valid entries, arrays for damaged entries and
 454          * an array for gap seek positions. If you call this method on your own,
 455          * please re-analyze the file structure. So you are better to call
 456          * analyzeFile() instead of this method.
 457          *
 458          * @return      void
 459          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 460          */
 461         public function initCountersGapsArray () {
 462                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 463         }
 464
 465         /**
 466          * Getter for header size
 467          *
 468          * @return      $totalEntries   Size of file header
 469          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 470          */
 471         public final function getHeaderSize () {
 472                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 473         }
 474
 475         /**
 476          * Setter for header size
 477          *
 478          * @param       $headerSize             Size of file header
 479          * @return      void
 480          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 481          */
 482         public final function setHeaderSize ($headerSize) {
 483                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 484         }
 485
 486         /**
 487          * Getter for header array
 488          *
 489          * @return      $totalEntries   Size of file header
 490          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 491          */
 492         public final function getHeader () {
 493                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 494         }
 495
 496         /**
 497          * Setter for header
 498          *
 499          * @param       $header         Array for a file header
 500          * @return      void
 501          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 502          */
 503         public final function setHeader (array $header) {
 504                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 505         }
 506
 507         /**
 508          * Updates seekPosition attribute from file to avoid to much access on file.
 509          *
 510          * @return      void
 511          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 512          */
 513         public function updateSeekPosition () {
 514                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 515         }
 516
 517         /**
 518          * Getter for total entries
 519          *
 520          * @return      $totalEntries   Total entries in this file
 521          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 522          */
 523         public final function getCounter () {
 524                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 525         }
 526
 527         /**
 528          * Writes data at given position
 529          *
 530          * @param       $seekPosition   Seek position
 531          * @param       $data                   Data to be written
 532          * @param       $flushHeader    Whether to flush the header (default: flush)
 533          * @return      void
 534          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 535          */
 536         public function writeData ($seekPosition, $data, $flushHeader = true) {
 537                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data[]=%s,flushHeader=%d', __METHOD__, __LINE__, $seekPosition, gettype($data), intval($flushHeader)));
 538                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 539         }
 540
 541         /**
 542          * Writes given value to the file and returns a hash and gap position for it
 543          *
 544          * @param       $groupId        Group identifier
 545          * @param       $value          Value to be added to the stack
 546          * @return      $data           Hash and gap position
 547          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 548          */
 549         public function writeValueToFile ($groupId, $value) {
 550                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,value[%s]=%s', __METHOD__, __LINE__, $groupId, gettype($value), print_r($value, true)));
 551                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 552         }
 553
 554         /**
 555          * Searches for next suitable gap the given length of data can fit in
 556          * including padding bytes.
 557          *
 558          * @param       $length                 Length of raw data
 559          * @return      $seekPosition   Found next gap's seek position
 560          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 561          */
 562         public function searchNextGap ($length) {
 563                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] length=%s', __METHOD__, __LINE__, $length));
 564                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 565         }
 566
 567         /**
 568          * "Getter" for file size
 569          *
 570          * @return      $fileSize       Size of currently loaded file
 571          */
 572         public function getFileSize () {
 573                 // Call iterator's method
 574                 return $this->getIteratorInstance()->getFileSize();
 575         }
 576
 577         /**
 578          * Writes given raw data to the file and returns a gap position and length
 579          *
 580          * @param       $groupId        Group identifier
 581          * @param       $hash           Hash from encoded value
 582          * @param       $encoded        Encoded value to be written to the file
 583          * @return      $data           Gap position and length of the raw data
 584          */
 585         public function writeDataToFreeGap ($groupId, $hash, $encoded) {
 586                 // Debug message
 587                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,encoded()=%d - CALLED!', __METHOD__, __LINE__, $groupId, $hash, strlen($encoded)));
 588
 589                 // Raw data been written to the file
 590                 $rawData = sprintf('%s%s%s%s%s',
 591                         $groupId,
 592                         BaseBinaryFile::SEPARATOR_GROUP_HASH,
 593                         hex2bin($hash),
 594                         BaseBinaryFile::SEPARATOR_HASH_VALUE,
 595                         $encoded
 596                 );
 597
 598                 // Debug message
 599                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d', __METHOD__, __LINE__, $groupId, $hash, strlen($rawData)));
 600
 601                 // Search for next free gap
 602                 $gapPosition = $this->getIteratorInstance()->searchNextGap(strlen($rawData));
 603
 604                 // Gap position cannot be smaller than header length + 1
 605                 assert($gapPosition > $this->getIteratorInstance()->getHeaderSize());
 606
 607                 // Debug message
 608                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,gapPosition=%s', __METHOD__, __LINE__, $groupId, $hash, $gapPosition));
 609
 610                 // Then write the data at that gap
 611                 $this->getIteratorInstance()->writeData($gapPosition, $rawData);
 612
 613                 // Debug message
 614                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d - EXIT!', __METHOD__, __LINE__, $groupId, $hash, strlen($rawData)));
 615
 616                 // Return gap position, hash and length of raw data
 617                 return array(
 618                         self::ARRAY_INDEX_GAP_POSITION => $gapPosition,
 619                         self::ARRAY_INDEX_HASH         => $hash,
 620                         self::ARRAY_INDEX_DATA_LENGTH  => strlen($rawData)
 621                 );
 622         }
 623
 624 }