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

   1 <?php
   2 // Own namespace
   3 namespace Org\Mxchange\CoreFramework\Stacker\Filesystem;
   4
   5 // Import framework stuff
   6 use Org\Mxchange\CoreFramework\Factory\Filesystem\Stack\FileStackIndexFactory;
   7 use Org\Mxchange\CoreFramework\Factory\ObjectFactory;
   8 use Org\Mxchange\CoreFramework\FileStack\InvalidMagicException;
   9 use Org\Mxchange\CoreFramework\Filesystem\File\BaseBinaryFile;
  10 use Org\Mxchange\CoreFramework\Generic\UnsupportedOperationException;
  11 use Org\Mxchange\CoreFramework\Index\Indexable;
  12 use Org\Mxchange\CoreFramework\Iterator\Filesystem\SeekableWritableFileIterator;
  13 use Org\Mxchange\CoreFramework\Stacker\BaseStacker;
  14 use Org\Mxchange\CoreFramework\Utils\String\StringUtils;
  15
  16 // Import SPL stuff
  17 use \SplFileInfo;
  18 use \UnexpectedValueException;
  19
  20 /**
  21  * A general file-based stack class
  22  *
  23  * @author              Roland Haeder <webmaster@ship-simu.org>
  24  * @version             0.0.0
  25  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2020 Core Developer Team
  26  * @license             GNU GPL 3.0 or any newer version
  27  * @link                http://www.ship-simu.org
  28  *
  29  * This program is free software: you can redistribute it and/or modify
  30  * it under the terms of the GNU General Public License as published by
  31  * the Free Software Foundation, either version 3 of the License, or
  32  * (at your option) any later version.
  33  *
  34  * This program is distributed in the hope that it will be useful,
  35  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  36  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  37  * GNU General Public License for more details.
  38  *
  39  * You should have received a copy of the GNU General Public License
  40  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  41  */
  42 abstract class BaseFileStack extends BaseStacker {
  43         // Exception codes
  44         const EXCEPTION_BAD_MAGIC = 0xe100;
  45
  46         /**
  47          * Magic for this stack
  48          */
  49         const STACK_MAGIC = 'STACKv0.1';
  50
  51         /**
  52          * Name of array index for gap position
  53          */
  54         const ARRAY_INDEX_GAP_POSITION = 'gap';
  55
  56         /**
  57          * Name of array index for hash
  58          */
  59         const ARRAY_INDEX_HASH = 'hash';
  60
  61         /**
  62          * Name of array index for length of raw data
  63          */
  64         const ARRAY_INDEX_DATA_LENGTH = 'length';
  65
  66         /**
  67          * An instance of an Indexable class
  68          */
  69         private $indexInstance = NULL;
  70
  71         /**
  72          * Protected constructor
  73          *
  74          * @param       $className      Name of the class
  75          * @return      void
  76          */
  77         protected function __construct (string $className) {
  78                 // Call parent constructor
  79                 parent::__construct($className);
  80         }
  81
  82         /**
  83          * Setter for Indexable instance
  84          *
  85          * @param       $indexInstance  An instance of an Indexable class
  86          * @return      void
  87          */
  88         protected final function setIndexInstance (Indexable $indexInstance) {
  89                 $this->indexInstance = $indexInstance;
  90         }
  91
  92         /**
  93          * Getter for Indexable instance
  94          *
  95          * @return      $indexInstance  An instance of an Indexable class
  96          */
  97         public final function getIndexInstance () {
  98                 return $this->indexInstance;
  99         }
 100
 101         /**
 102          * Reads the file header
 103          *
 104          * @return      void
 105          * @todo        To hard assertions here, better rewrite them to exceptions
 106          * @throws      UnexpectedValueException        If header is not proper length
 107          * @throws      InvalidMagicException   If a bad magic was found
 108          */
 109         public function readFileHeader () {
 110                 // First rewind to beginning as the header sits at the beginning ...
 111                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: CALLED!', __METHOD__, __LINE__));
 112                 $this->getIteratorInstance()->rewind();
 113
 114                 // Then read it (see constructor for calculation)
 115                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
 116                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Read %d bytes (%d wanted).', strlen($data), $this->getIteratorInstance()->getHeaderSize()));
 117
 118                 // Have all requested bytes been read?
 119                 if (strlen($data) != $this->getIteratorInstance()->getHeaderSize()) {
 120                         // Bad data length
 121                         throw new UnexpectedValueException(sprintf('data(%d)=%s does not match iteratorInstance->headerSize=%d',
 122                                 strlen($data),
 123                                 $data,
 124                                 $this->getIteratorInstance()->getHeaderSize()
 125                         ));
 126                 }
 127
 128                 // Last character must be the separator
 129                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: data(-1)=%s', dechex(ord(substr($data, -1, 1)))));
 130                 if (substr($data, -1, 1) !== chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)) {
 131                         // Not valid separator
 132                         throw new UnexpectedValueException(sprintf('data=%s does not have separator=%s at the end.',
 133                                 $data,
 134                                 BaseBinaryFile::SEPARATOR_HEADER_ENTRIES
 135                         ));
 136                 }
 137
 138                 // Okay, then remove it
 139                 $data = substr($data, 0, -1);
 140
 141                 // And update seek position
 142                 $this->getIteratorInstance()->updateSeekPosition();
 143
 144                 /*
 145                  * Now split it:
 146                  *
 147                  * 0 => magic
 148                  * 1 => total entries
 149                  * 2 => current seek position
 150                  */
 151                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
 152
 153                 // Set header here
 154                 $this->getIteratorInstance()->setHeader($header);
 155
 156                 // Check if the array has only 3 elements
 157                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: header(%d)=%s', count($header), print_r($header, true)));
 158                 if (count($header) != 3) {
 159                         // Header array count is not expected
 160                         throw new UnexpectedValueException(sprintf('data=%s has %d elements, expected 3',
 161                                 $data,
 162                                 count($header)
 163                         ));
 164                 } elseif ($header[0] != self::STACK_MAGIC) {
 165                         // Bad magic
 166                         throw new InvalidMagicException($data, self::EXCEPTION_BAD_MAGIC);
 167                 }
 168
 169                 // Check length of count and seek position
 170                 if (strlen($header[1]) != BaseBinaryFile::LENGTH_COUNT) {
 171                         // Count length not valid
 172                         throw new UnexpectedValueException(sprintf('header[1](%d)=%s is not expected %d length',
 173                                 strlen($header[1]),
 174                                 $header[1],
 175                                 BaseBinaryFile::LENGTH_COUNT
 176                         ));
 177                 } elseif (strlen($header[1]) != BaseBinaryFile::LENGTH_POSITION) {
 178                         // Position length not valid
 179                         throw new UnexpectedValueException(sprintf('header[2](%d)=%s is not expected %d length',
 180                                 strlen($header[1]),
 181                                 $header[1],
 182                                 BaseBinaryFile::LENGTH_POSITION
 183                         ));
 184                 }
 185
 186                 // Decode count and seek position
 187                 $header[1] = hex2bin($header[1]);
 188                 $header[2] = hex2bin($header[2]);
 189
 190                 // Trace message
 191                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: EXIT!', __METHOD__, __LINE__));
 192         }
 193
 194         /**
 195          * Flushes the file header
 196          *
 197          * @return      void
 198          */
 199         public function flushFileHeader () {
 200                 // Put all informations together
 201                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: CALLED!', __METHOD__, __LINE__));
 202                 $header = sprintf('%s%s%s%s%s%s',
 203                         // Magic
 204                         self::STACK_MAGIC,
 205
 206                         // Separator magic<->count
 207                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 208
 209                         // Total entries (will be zero) and pad it to 20 chars
 210                         str_pad(StringUtils::dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 211
 212                         // Separator count<->seek position
 213                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 214
 215                         // Position (will be zero)
 216                         str_pad(StringUtils::dec2hex($this->getIteratorInstance()->getSeekPosition(), 2), BaseBinaryFile::LENGTH_POSITION, '0', STR_PAD_LEFT),
 217
 218                         // Separator position<->entries
 219                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 220                 );
 221
 222                 // Write it to disk (header is always at seek position 0)
 223                 $this->getIteratorInstance()->writeData(0, $header, false);
 224
 225                 // Trace message
 226                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: EXIT!', __METHOD__, __LINE__));
 227         }
 228
 229         /**
 230          * Initializes this file-based stack.
 231          *
 232          * @param       $fileInfoInstance       An instance of a SplFileInfo class
 233          * @param       $type           Type of this stack (e.g. url_source for URL sources)
 234          * @return      void
 235          * @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.
 236          */
 237         protected function initFileStack (SplFileInfo $fileInfoInstance, string $type) {
 238                 // Get a stack file instance
 239                 $fileInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileInfoInstance, $this));
 240
 241                 // Get iterator instance
 242                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 243
 244                 // Is the instance implementing the right interface?
 245                 assert($iteratorInstance instanceof SeekableWritableFileIterator);
 246
 247                 // Set iterator here
 248                 $this->setIteratorInstance($iteratorInstance);
 249
 250                 // Calculate header size
 251                 $this->getIteratorInstance()->setHeaderSize(
 252                         strlen(self::STACK_MAGIC) +
 253                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 254                         BaseBinaryFile::LENGTH_COUNT +
 255                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 256                         BaseBinaryFile::LENGTH_POSITION +
 257                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 258                 );
 259
 260                 // Init counters and gaps array
 261                 $this->getIteratorInstance()->initCountersGapsArray();
 262
 263                 // Is the file's header initialized?
 264                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 265                         // No, then create it (which may pre-allocate the stack)
 266                         $this->getIteratorInstance()->createFileHeader();
 267
 268                         // And pre-allocate a bit
 269                         $this->getIteratorInstance()->preAllocateFile('file_stack');
 270                 } // END - if
 271
 272                 // Load the file header
 273                 $this->readFileHeader();
 274
 275                 // Count all entries in file
 276                 $this->getIteratorInstance()->analyzeFile();
 277
 278                 /*
 279                  * Get stack index instance. This can be used for faster
 280                  * "defragmentation" and startup.
 281                  */
 282                 $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileInfoInstance, $type);
 283
 284                 // And set it here
 285                 $this->setIndexInstance($indexInstance);
 286         }
 287
 288         /**
 289          * Adds a value to given stack
 290          *
 291          * @param       $stackerName    Name of the stack
 292          * @param       $value                  Value to add to this stacker
 293          * @return      void
 294          * @throws      FullStackerException    If the stack is full
 295          */
 296         protected function addValue (string $stackerName, $value) {
 297                 // Do some tests
 298                 if ($this->isStackFull($stackerName)) {
 299                         // Stacker is full
 300                         throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
 301                 } // END - if
 302
 303                 // No objects/resources are allowed as their serialization takes to long
 304                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName . ',value[' . gettype($value) . ']=' . print_r($value, true));
 305                 assert(!is_object($value));
 306                 assert(!is_resource($value));
 307
 308                 /*
 309                  * Now add the value to the file stack which returns gap position, a
 310                  * hash and length of the raw data.
 311                  */
 312                 $data = $this->getIteratorInstance()->writeValueToFile($stackerName, $value);
 313
 314                 // Add the hash and gap position to the index
 315                 $this->getIndexInstance()->addHashToIndex($stackerName, $data);
 316         }
 317
 318         /**
 319          * Get last value from named stacker
 320          *
 321          * @param       $stackerName    Name of the stack
 322          * @return      $value                  Value of last added value
 323          * @throws      EmptyStackerException   If the stack is empty
 324          */
 325         protected function getLastValue (string $stackerName) {
 326                 // Is the stack not yet initialized or full?
 327                 if ($this->isStackEmpty($stackerName)) {
 328                         // Throw an exception
 329                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 330                 } // END - if
 331
 332                 // Now get the last value
 333                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 334                 $value = NULL;
 335
 336                 // Return it
 337                 return $value;
 338         }
 339
 340         /**
 341          * Get first value from named stacker
 342          *
 343          * @param       $stackerName    Name of the stack
 344          * @return      $value                  Value of last added value
 345          * @throws      EmptyStackerException   If the stack is empty
 346          */
 347         protected function getFirstValue (string $stackerName) {
 348                 // Is the stack not yet initialized or full?
 349                 if ($this->isStackEmpty($stackerName)) {
 350                         // Throw an exception
 351                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 352                 } // END - if
 353
 354                 // Now get the first value
 355                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 356                 $value = NULL;
 357
 358                 // Return it
 359                 return $value;
 360         }
 361
 362         /**
 363          * "Pops" last entry from stack
 364          *
 365          * @param       $stackerName    Name of the stack
 366          * @return      $value                  Value "poped" from array
 367          * @throws      EmptyStackerException   If the stack is empty
 368          */
 369         protected function popLast (string $stackerName) {
 370                 // Is the stack not yet initialized or full?
 371                 if ($this->isStackEmpty($stackerName)) {
 372                         // Throw an exception
 373                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 374                 } // END - if
 375
 376                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 377                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 378                 return NULL;
 379         }
 380
 381         /**
 382          * "Pops" first entry from stack
 383          *
 384          * @param       $stackerName    Name of the stack
 385          * @return      $value                  Value "shifted" from array
 386          * @throws      EmptyStackerException   If the named stacker is empty
 387          */
 388         protected function popFirst (string $stackerName) {
 389                 // Is the stack not yet initialized or full?
 390                 if ($this->isStackEmpty($stackerName)) {
 391                         // Throw an exception
 392                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 393                 } // END - if
 394
 395                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 396                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 397                 return NULL;
 398         }
 399
 400         /**
 401          * Checks whether the given stack is full
 402          *
 403          * @param       $stackerName    Name of the stack
 404          * @return      $isFull                 Whether the stack is full
 405          */
 406         protected function isStackFull (string $stackerName) {
 407                 // File-based stacks will only run full if the disk space is low.
 408                 // @TODO Please implement this, returning false
 409                 $isFull = false;
 410
 411                 // Return result
 412                 return $isFull;
 413         }
 414
 415         /**
 416          * Checks whether the given stack is empty
 417          *
 418          * @param       $stackerName            Name of the stack
 419          * @return      $isEmpty                        Whether the stack is empty
 420          * @throws      NoStackerException      If given stack is missing
 421          */
 422         public function isStackEmpty (string $stackerName) {
 423                 // So, is the stack empty?
 424                 $isEmpty = (($this->getStackCount($stackerName)) == 0);
 425
 426                 // Return result
 427                 return $isEmpty;
 428         }
 429
 430         /**
 431          * Initializes given stacker
 432          *
 433          * @param       $stackerName    Name of the stack
 434          * @param       $forceReInit    Force re-initialization
 435          * @return      void
 436          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 437          */
 438         public function initStack (string $stackerName, bool $forceReInit = false) {
 439                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 440         }
 441
 442         /**
 443          * Initializes all stacks
 444          *
 445          * @return      void
 446          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 447          */
 448         public function initStacks (array $stacks, bool $forceReInit = false) {
 449                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 450         }
 451
 452         /**
 453          * Checks whether the given stack is initialized (set in array $stackers)
 454          *
 455          * @param       $stackerName    Name of the stack
 456          * @return      $isInitialized  Whether the stack is initialized
 457          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 458          */
 459         public function isStackInitialized (string $stackerName) {
 460                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 461         }
 462
 463         /**
 464          * Determines whether the EOF has been reached
 465          *
 466          * @return      $isEndOfFileReached             Whether the EOF has been reached
 467          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 468          */
 469         public function isEndOfFileReached () {
 470                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 471         }
 472
 473         /**
 474          * Getter for size of given stack (array count)
 475          *
 476          * @param       $stackerName    Name of the stack
 477          * @return      $count                  Size of stack (array count)
 478          */
 479         public function getStackCount (string $stackerName) {
 480                 // Now, simply return the found count value, this must be up-to-date then!
 481                 return $this->getIteratorInstance()->getCounter();
 482         }
 483
 484         /**
 485          * Calculates minimum length for one entry/block
 486          *
 487          * @return      $length         Minimum length for one entry/block
 488          */
 489         public function calculateMinimumBlockLength () {
 490                 // Calulcate it
 491                 $length =
 492                         // Length of entry group
 493                         BaseBinaryFile::LENGTH_GROUP + strlen(chr(BaseBinaryFile::SEPARATOR_GROUP_HASH)) +
 494                         // Hash + value
 495                         self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
 496                         // Final separator
 497                         strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 498
 499                 // Return it
 500                 return $length;
 501         }
 502
 503         /**
 504          * Initializes counter for valid entries, arrays for damaged entries and
 505          * an array for gap seek positions. If you call this method on your own,
 506          * please re-analyze the file structure. So you are better to call
 507          * analyzeFile() instead of this method.
 508          *
 509          * @return      void
 510          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 511          */
 512         public function initCountersGapsArray () {
 513                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 514         }
 515
 516         /**
 517          * Getter for header size
 518          *
 519          * @return      $totalEntries   Size of file header
 520          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 521          */
 522         public final function getHeaderSize () {
 523                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 524         }
 525
 526         /**
 527          * Setter for header size
 528          *
 529          * @param       $headerSize             Size of file header
 530          * @return      void
 531          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 532          */
 533         public final function setHeaderSize (int $headerSize) {
 534                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 535         }
 536
 537         /**
 538          * Getter for header array
 539          *
 540          * @return      $totalEntries   Size of file header
 541          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 542          */
 543         public final function getHeader () {
 544                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 545         }
 546
 547         /**
 548          * Setter for header
 549          *
 550          * @param       $header         Array for a file header
 551          * @return      void
 552          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 553          */
 554         public final function setHeader (array $header) {
 555                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 556         }
 557
 558         /**
 559          * Updates seekPosition attribute from file to avoid to much access on file.
 560          *
 561          * @return      void
 562          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 563          */
 564         public function updateSeekPosition () {
 565                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 566         }
 567
 568         /**
 569          * Getter for total entries
 570          *
 571          * @return      $totalEntries   Total entries in this file
 572          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 573          */
 574         public final function getCounter () {
 575                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 576         }
 577
 578         /**
 579          * Writes data at given position
 580          *
 581          * @param       $seekPosition   Seek position
 582          * @param       $data                   Data to be written
 583          * @param       $flushHeader    Whether to flush the header (default: flush)
 584          * @return      void
 585          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 586          */
 587         public function writeData ($seekPosition, $data, bool $flushHeader = true) {
 588                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: seekPosition=%s,data[]=%s,flushHeader=%d', $seekPosition, gettype($data), intval($flushHeader)));
 589                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 590         }
 591
 592         /**
 593          * Writes given value to the file and returns a hash and gap position for it
 594          *
 595          * @param       $groupId        Group identifier
 596          * @param       $value          Value to be added to the stack
 597          * @return      $data           Hash and gap position
 598          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 599          */
 600         public function writeValueToFile ($groupId, $value) {
 601                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,value[%s]=%s', $groupId, gettype($value), print_r($value, true)));
 602                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 603         }
 604
 605         /**
 606          * Searches for next suitable gap the given length of data can fit in
 607          * including padding bytes.
 608          *
 609          * @param       $length                 Length of raw data
 610          * @return      $seekPosition   Found next gap's seek position
 611          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 612          */
 613         public function searchNextGap (int $length) {
 614                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: length=%s', $length));
 615                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 616         }
 617
 618         /**
 619          * "Getter" for file size
 620          *
 621          * @return      $fileSize       Size of currently loaded file
 622          */
 623         public function getFileSize () {
 624                 // Call iterator's method
 625                 return $this->getIteratorInstance()->getFileSize();
 626         }
 627
 628         /**
 629          * Writes given raw data to the file and returns a gap position and length
 630          *
 631          * @param       $groupId        Group identifier
 632          * @param       $hash           Hash from encoded value
 633          * @param       $encoded        Encoded value to be written to the file
 634          * @return      $data           Gap position and length of the raw data
 635          */
 636         public function writeDataToFreeGap ($groupId, string $hash, $encoded) {
 637                 // Raw data been written to the file
 638                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,encoded()=%d - CALLED!', $groupId, $hash, strlen($encoded)));
 639                 $rawData = sprintf('%s%s%s%s%s',
 640                         $groupId,
 641                         BaseBinaryFile::SEPARATOR_GROUP_HASH,
 642                         hex2bin($hash),
 643                         BaseBinaryFile::SEPARATOR_HASH_VALUE,
 644                         $encoded
 645                 );
 646
 647                 // Search for next free gap
 648                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,rawData()=%d', $groupId, $hash, strlen($rawData)));
 649                 $gapPosition = $this->getIteratorInstance()->searchNextGap(strlen($rawData));
 650
 651                 // Gap position cannot be smaller than header length + 1
 652                 assert($gapPosition > $this->getIteratorInstance()->getHeaderSize());
 653
 654                 // Then write the data at that gap
 655                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,gapPosition=%s', $groupId, $hash, $gapPosition));
 656                 $this->getIteratorInstance()->writeData($gapPosition, $rawData);
 657
 658                 // Return gap position, hash and length of raw data
 659                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,rawData()=%d - EXIT!', $groupId, $hash, strlen($rawData)));
 660                 return [
 661                         self::ARRAY_INDEX_GAP_POSITION => $gapPosition,
 662                         self::ARRAY_INDEX_HASH         => $hash,
 663                         self::ARRAY_INDEX_DATA_LENGTH  => strlen($rawData),
 664                 ];
 665         }
 666
 667 }