inc/main/classes/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 - 2015 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          * Name of array index for gap position
  32          */
  33         const ARRAY_INDEX_GAP_POSITION = 'gap';
  34
  35         /**
  36          * Name of array index for hash
  37          */
  38         const ARRAY_INDEX_HASH = 'hash';
  39
  40         /**
  41          * Name of array index for length of raw data
  42          */
  43         const ARRAY_INDEX_DATA_LENGTH = 'length';
  44
  45         /**
  46          * Protected constructor
  47          *
  48          * @param       $className      Name of the class
  49          * @return      void
  50          */
  51         protected function __construct ($className) {
  52                 // Call parent constructor
  53                 parent::__construct($className);
  54         }
  55
  56         /**
  57          * Reads the file header
  58          *
  59          * @return      void
  60          * @todo        To hard assertions here, better rewrite them to exceptions
  61          */
  62         public function readFileHeader () {
  63                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
  64
  65                 // First rewind to beginning as the header sits at the beginning ...
  66                 $this->getIteratorInstance()->rewind();
  67
  68                 // Then read it (see constructor for calculation)
  69                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
  70                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->getIteratorInstance()->getHeaderSize()));
  71
  72                 // Have all requested bytes been read?
  73                 assert(strlen($data) == $this->getIteratorInstance()->getHeaderSize());
  74                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  75
  76                 // Last character must be the separator
  77                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
  78                 assert(substr($data, -1, 1) == chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES));
  79                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  80
  81                 // Okay, then remove it
  82                 $data = substr($data, 0, -1);
  83
  84                 // And update seek position
  85                 $this->getIteratorInstance()->updateSeekPosition();
  86
  87                 /*
  88                  * Now split it:
  89                  *
  90                  * 0 => magic
  91                  * 1 => total entries
  92                  * 2 => current seek position
  93                  */
  94                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
  95
  96                 // Set header here
  97                 $this->getIteratorInstance()->setHeader($header);
  98
  99                 // Check if the array has only 3 elements
 100                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($header), print_r($header, TRUE)));
 101                 assert(count($header) == 3);
 102                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 103
 104                 // Check magic
 105                 assert($header[0] == self::STACK_MAGIC);
 106                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 107
 108                 // Check length of count and seek position
 109                 assert(strlen($header[1]) == BaseBinaryFile::LENGTH_COUNT);
 110                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 111                 assert(strlen($header[2]) == BaseBinaryFile::LENGTH_POSITION);
 112                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 113
 114                 // Decode count and seek position
 115                 $header[1] = hex2bin($header[1]);
 116                 $header[2] = hex2bin($header[2]);
 117
 118                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 119         }
 120
 121         /**
 122          * Flushes the file header
 123          *
 124          * @return      void
 125          */
 126         public function flushFileHeader () {
 127                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 128
 129                 // Put all informations together
 130                 $header = sprintf('%s%s%s%s%s%s',
 131                         // Magic
 132                         self::STACK_MAGIC,
 133
 134                         // Separator magic<->count
 135                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 136
 137                         // Total entries (will be zero) and pad it to 20 chars
 138                         str_pad($this->dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 139
 140                         // Separator count<->seek position
 141                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 142
 143                         // Position (will be zero)
 144                         str_pad($this->dec2hex($this->getIteratorInstance()->getSeekPosition(), 2), BaseBinaryFile::LENGTH_POSITION, '0', STR_PAD_LEFT),
 145
 146                         // Separator position<->entries
 147                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 148                 );
 149
 150                 // Write it to disk (header is always at seek position 0)
 151                 $this->getIteratorInstance()->writeData(0, $header, FALSE);
 152
 153                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 154         }
 155
 156         /**
 157          * Initializes this file-based stack.
 158          *
 159          * @param       $fileName       File name of this stack
 160          * @param       $type           Type of this stack (e.g. url_source for URL sources)
 161          * @return      void
 162          * @todo        Currently the stack file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole stack file.
 163          */
 164         protected function initFileStack ($fileName, $type) {
 165                 // Get a stack file instance
 166                 $fileInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileName, $this));
 167
 168                 // Get iterator instance
 169                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 170
 171                 // Is the instance implementing the right interface?
 172                 assert($iteratorInstance instanceof SeekableWritableFileIterator);
 173
 174                 // Set iterator here
 175                 $this->setIteratorInstance($iteratorInstance);
 176
 177                 // Calculate header size
 178                 $this->getIteratorInstance()->setHeaderSize(
 179                         strlen(self::STACK_MAGIC) +
 180                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 181                         BaseBinaryFile::LENGTH_COUNT +
 182                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 183                         BaseBinaryFile::LENGTH_POSITION +
 184                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 185                 );
 186
 187                 // Init counters and gaps array
 188                 $this->getIteratorInstance()->initCountersGapsArray();
 189
 190                 // Is the file's header initialized?
 191                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 192                         // No, then create it (which may pre-allocate the stack)
 193                         $this->getIteratorInstance()->createFileHeader();
 194
 195                         // And pre-allocate a bit
 196                         $this->getIteratorInstance()->preAllocateFile('file_stack');
 197                 } // END - if
 198
 199                 // Load the file header
 200                 $this->readFileHeader();
 201
 202                 // Count all entries in file
 203                 $this->getIteratorInstance()->analyzeFile();
 204
 205                 /*
 206                  * Get stack index instance. This can be used for faster
 207                  * "defragmentation" and startup.
 208                  */
 209                 $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileName, $type);
 210
 211                 // And set it here
 212                 $this->setIndexInstance($indexInstance);
 213         }
 214
 215         /**
 216          * Adds a value to given stack
 217          *
 218          * @param       $stackerName    Name of the stack
 219          * @param       $value                  Value to add to this stacker
 220          * @return      void
 221          * @throws      FullStackerException    If the stack is full
 222          */
 223         protected function addValue ($stackerName, $value) {
 224                 // Do some tests
 225                 if ($this->isStackFull($stackerName)) {
 226                         // Stacker is full
 227                         throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
 228                 } // END - if
 229
 230                 // Debug message
 231                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName . ',value[' . gettype($value) . ']=' . print_r($value, TRUE));
 232
 233                 // No objects/resources are allowed as their serialization takes to long
 234                 assert(!is_object($value));
 235                 assert(!is_resource($value));
 236
 237                 /*
 238                  * Now add the value to the file stack which returns gap position, a
 239                  * hash and length of the raw data.
 240                  */
 241                 $data = $this->getIteratorInstance()->writeValueToFile($stackerName, $value);
 242
 243                 // Add the hash and gap position to the index
 244                 $this->getIndexInstance()->addHashToIndex($stackerName, $data);
 245         }
 246
 247         /**
 248          * Get last value from named stacker
 249          *
 250          * @param       $stackerName    Name of the stack
 251          * @return      $value                  Value of last added value
 252          * @throws      EmptyStackerException   If the stack is empty
 253          */
 254         protected function getLastValue ($stackerName) {
 255                 // Is the stack not yet initialized or full?
 256                 if ($this->isStackEmpty($stackerName)) {
 257                         // Throw an exception
 258                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 259                 } // END - if
 260
 261                 // Now get the last value
 262                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 263                 $value = NULL;
 264
 265                 // Return it
 266                 return $value;
 267         }
 268
 269         /**
 270          * Get first value from named stacker
 271          *
 272          * @param       $stackerName    Name of the stack
 273          * @return      $value                  Value of last added value
 274          * @throws      EmptyStackerException   If the stack is empty
 275          */
 276         protected function getFirstValue ($stackerName) {
 277                 // Is the stack not yet initialized or full?
 278                 if ($this->isStackEmpty($stackerName)) {
 279                         // Throw an exception
 280                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 281                 } // END - if
 282
 283                 // Now get the first value
 284                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 285                 $value = NULL;
 286
 287                 // Return it
 288                 return $value;
 289         }
 290
 291         /**
 292          * "Pops" last entry from stack
 293          *
 294          * @param       $stackerName    Name of the stack
 295          * @return      $value                  Value "poped" from array
 296          * @throws      EmptyStackerException   If the stack is empty
 297          */
 298         protected function popLast ($stackerName) {
 299                 // Is the stack not yet initialized or full?
 300                 if ($this->isStackEmpty($stackerName)) {
 301                         // Throw an exception
 302                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 303                 } // END - if
 304
 305                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 306                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 307                 return NULL;
 308         }
 309
 310         /**
 311          * "Pops" first entry from stack
 312          *
 313          * @param       $stackerName    Name of the stack
 314          * @return      $value                  Value "shifted" from array
 315          * @throws      EmptyStackerException   If the named stacker is empty
 316          */
 317         protected function popFirst ($stackerName) {
 318                 // Is the stack not yet initialized or full?
 319                 if ($this->isStackEmpty($stackerName)) {
 320                         // Throw an exception
 321                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 322                 } // END - if
 323
 324                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 325                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 326                 return NULL;
 327         }
 328
 329         /**
 330          * Checks whether the given stack is full
 331          *
 332          * @param       $stackerName    Name of the stack
 333          * @return      $isFull                 Whether the stack is full
 334          */
 335         protected function isStackFull ($stackerName) {
 336                 // File-based stacks will only run full if the disk space is low.
 337                 // @TODO Please implement this, returning FALSE
 338                 $isFull = FALSE;
 339
 340                 // Return result
 341                 return $isFull;
 342         }
 343
 344         /**
 345          * Checks whether the given stack is empty
 346          *
 347          * @param       $stackerName            Name of the stack
 348          * @return      $isEmpty                        Whether the stack is empty
 349          * @throws      NoStackerException      If given stack is missing
 350          */
 351         public function isStackEmpty ($stackerName) {
 352                 // So, is the stack empty?
 353                 $isEmpty = (($this->getStackCount($stackerName)) == 0);
 354
 355                 // Return result
 356                 return $isEmpty;
 357         }
 358
 359         /**
 360          * Initializes given stacker
 361          *
 362          * @param       $stackerName    Name of the stack
 363          * @param       $forceReInit    Force re-initialization
 364          * @return      void
 365          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 366          */
 367         public function initStack ($stackerName, $forceReInit = FALSE) {
 368                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 369         }
 370
 371         /**
 372          * Initializes all stacks
 373          *
 374          * @return      void
 375          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 376          */
 377         public function initStacks (array $stacks, $forceReInit = FALSE) {
 378                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 379         }
 380
 381         /**
 382          * Checks whether the given stack is initialized (set in array $stackers)
 383          *
 384          * @param       $stackerName    Name of the stack
 385          * @return      $isInitialized  Whether the stack is initialized
 386          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 387          */
 388         public function isStackInitialized ($stackerName) {
 389                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 390         }
 391
 392         /**
 393          * Determines whether the EOF has been reached
 394          *
 395          * @return      $isEndOfFileReached             Whether the EOF has been reached
 396          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 397          */
 398         public function isEndOfFileReached () {
 399                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 400         }
 401
 402         /**
 403          * Getter for file name
 404          *
 405          * @return      $fileName       The current file name
 406          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 407          */
 408         public function getFileName () {
 409                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 410         }
 411
 412         /**
 413          * Getter for size of given stack (array count)
 414          *
 415          * @param       $stackerName    Name of the stack
 416          * @return      $count                  Size of stack (array count)
 417          */
 418         public function getStackCount ($stackerName) {
 419                 // Now, simply return the found count value, this must be up-to-date then!
 420                 return $this->getIteratorInstance()->getCounter();
 421         }
 422
 423         /**
 424          * Calculates minimum length for one entry/block
 425          *
 426          * @return      $length         Minimum length for one entry/block
 427          */
 428         public function calculateMinimumBlockLength () {
 429                 // Calulcate it
 430                 $length =
 431                         // Length of entry group
 432                         BaseBinaryFile::LENGTH_GROUP + strlen(chr(BaseBinaryFile::SEPARATOR_GROUP_HASH)) +
 433                         // Hash + value
 434                         self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
 435                         // Final separator
 436                         strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 437
 438                 // Return it
 439                 return $length;
 440         }
 441
 442         /**
 443          * Initializes counter for valid entries, arrays for damaged entries and
 444          * an array for gap seek positions. If you call this method on your own,
 445          * please re-analyze the file structure. So you are better to call
 446          * analyzeFile() instead of this method.
 447          *
 448          * @return      void
 449          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 450          */
 451         public function initCountersGapsArray () {
 452                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 453         }
 454
 455         /**
 456          * Getter for header size
 457          *
 458          * @return      $totalEntries   Size of file header
 459          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 460          */
 461         public final function getHeaderSize () {
 462                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 463         }
 464
 465         /**
 466          * Setter for header size
 467          *
 468          * @param       $headerSize             Size of file header
 469          * @return      void
 470          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 471          */
 472         public final function setHeaderSize ($headerSize) {
 473                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 474         }
 475
 476         /**
 477          * Getter for header array
 478          *
 479          * @return      $totalEntries   Size of file header
 480          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 481          */
 482         public final function getHeader () {
 483                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 484         }
 485
 486         /**
 487          * Setter for header
 488          *
 489          * @param       $header         Array for a file header
 490          * @return      void
 491          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 492          */
 493         public final function setHeader (array $header) {
 494                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 495         }
 496
 497         /**
 498          * Updates seekPosition attribute from file to avoid to much access on file.
 499          *
 500          * @return      void
 501          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 502          */
 503         public function updateSeekPosition () {
 504                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 505         }
 506
 507         /**
 508          * Getter for total entries
 509          *
 510          * @return      $totalEntries   Total entries in this file
 511          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 512          */
 513         public final function getCounter () {
 514                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 515         }
 516
 517         /**
 518          * Writes data at given position
 519          *
 520          * @param       $seekPosition   Seek position
 521          * @param       $data                   Data to be written
 522          * @param       $flushHeader    Whether to flush the header (default: flush)
 523          * @return      void
 524          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 525          */
 526         public function writeData ($seekPosition, $data, $flushHeader = TRUE) {
 527                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data[]=%s,flushHeader=%d', __METHOD__, __LINE__, $seekPosition, gettype($data), intval($flushHeader)));
 528                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 529         }
 530
 531         /**
 532          * Writes given value to the file and returns a hash and gap position for it
 533          *
 534          * @param       $groupId        Group identifier
 535          * @param       $value          Value to be added to the stack
 536          * @return      $data           Hash and gap position
 537          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 538          */
 539         public function writeValueToFile ($groupId, $value) {
 540                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,value[%s]=%s', __METHOD__, __LINE__, $groupId, gettype($value), print_r($value, TRUE)));
 541                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 542         }
 543
 544         /**
 545          * Searches for next suitable gap the given length of data can fit in
 546          * including padding bytes.
 547          *
 548          * @param       $length                 Length of raw data
 549          * @return      $seekPosition   Found next gap's seek position
 550          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 551          */
 552         public function searchNextGap ($length) {
 553                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] length=%s', __METHOD__, __LINE__, $length));
 554                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 555         }
 556
 557         /**
 558          * "Getter" for file size
 559          *
 560          * @return      $fileSize       Size of currently loaded file
 561          */
 562         public function getFileSize () {
 563                 // Call iterator's method
 564                 return $this->getIteratorInstance()->getFileSize();
 565         }
 566
 567         /**
 568          * Writes given raw data to the file and returns a gap position and length
 569          *
 570          * @param       $groupId        Group identifier
 571          * @param       $hash           Hash from encoded value
 572          * @param       $encoded        Encoded value to be written to the file
 573          * @return      $data           Gap position and length of the raw data
 574          */
 575         public function writeDataToFreeGap ($groupId, $hash, $encoded) {
 576                 // Debug message
 577                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,encoded()=%d - CALLED!', __METHOD__, __LINE__, $groupId, $hash, strlen($encoded)));
 578
 579                 // Raw data been written to the file
 580                 $rawData = sprintf('%s%s%s%s%s',
 581                         $groupId,
 582                         BaseBinaryFile::SEPARATOR_GROUP_HASH,
 583                         hex2bin($hash),
 584                         BaseBinaryFile::SEPARATOR_HASH_VALUE,
 585                         $encoded
 586                 );
 587
 588                 // Debug message
 589                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d', __METHOD__, __LINE__, $groupId, $hash, strlen($rawData)));
 590
 591                 // Search for next free gap
 592                 $gapPosition = $this->getIteratorInstance()->searchNextGap(strlen($rawData));
 593
 594                 // Gap position cannot be smaller than header length + 1
 595                 assert($gapPosition > $this->getIteratorInstance()->getHeaderSize());
 596
 597                 // Debug message
 598                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,gapPosition=%s', __METHOD__, __LINE__, $groupId, $hash, $gapPosition));
 599
 600                 // Then write the data at that gap
 601                 $this->getIteratorInstance()->writeData($gapPosition, $rawData);
 602
 603                 // Debug message
 604                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d - EXIT!', __METHOD__, __LINE__, $groupId, $hash, strlen($rawData)));
 605
 606                 // Return gap position, hash and length of raw data
 607                 return array(
 608                         self::ARRAY_INDEX_GAP_POSITION => $gapPosition,
 609                         self::ARRAY_INDEX_HASH         => $hash,
 610                         self::ARRAY_INDEX_DATA_LENGTH  => strlen($rawData)
 611                 );
 612         }
 613 }
 614
 615 // [EOF]
 616 ?>