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

   1 <?php
   2 /**
   3  * A general file-based stack class
   4  *
   5  * @author              Roland Haeder <webmaster@ship-simu.org>
   6  * @version             0.0.0
   7  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2013 Core Developer Team
   8  * @license             GNU GPL 3.0 or any newer version
   9  * @link                http://www.ship-simu.org
  10  *
  11  * This program is free software: you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation, either version 3 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  */
  24 class BaseFileStack extends BaseStacker {
  25         /**
  26          * Magic for this stack
  27          */
  28         const STACK_MAGIC = 'STACKv0.1';
  29
  30         /**
  31          * Protected constructor
  32          *
  33          * @param       $className      Name of the class
  34          * @return      void
  35          */
  36         protected function __construct ($className) {
  37                 // Call parent constructor
  38                 parent::__construct($className);
  39         }
  40
  41         /**
  42          * Reads the file header
  43          *
  44          * @return      void
  45          * @todo        To hard assertions here, better rewrite them to exceptions
  46          */
  47         public function readFileHeader () {
  48                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
  49
  50                 // First rewind to beginning as the header sits at the beginning ...
  51                 $this->getIteratorInstance()->rewind();
  52
  53                 // Then read it (see constructor for calculation)
  54                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
  55                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->getIteratorInstance()->getHeaderSize()));
  56
  57                 // Have all requested bytes been read?
  58                 assert(strlen($data) == $this->getIteratorInstance()->getHeaderSize());
  59                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  60
  61                 // Last character must be the separator
  62                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
  63                 assert(substr($data, -1, 1) == chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES));
  64                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  65
  66                 // Okay, then remove it
  67                 $data = substr($data, 0, -1);
  68
  69                 // And update seek position
  70                 $this->getIteratorInstance()->updateSeekPosition();
  71
  72                 /*
  73                  * Now split it:
  74                  *
  75                  * 0 => magic
  76                  * 1 => total entries
  77                  * 2 => current seek position
  78                  */
  79                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
  80
  81                 // Set header here
  82                 $this->getIteratorInstance()->setHeader($header);
  83
  84                 // Check if the array has only 3 elements
  85                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($header), print_r($header, TRUE)));
  86                 assert(count($header) == 3);
  87                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  88
  89                 // Check magic
  90                 assert($header[0] == self::STACK_MAGIC);
  91                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  92
  93                 // Check length of count and seek position
  94                 assert(strlen($header[1]) == BaseBinaryFile::LENGTH_COUNT);
  95                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  96                 assert(strlen($header[2]) == BaseBinaryFile::LENGTH_POSITION);
  97                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  98
  99                 // Decode count and seek position
 100                 $header[1] = hex2bin($header[1]);
 101                 $header[2] = hex2bin($header[2]);
 102
 103                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 104         }
 105
 106         /**
 107          * Flushes the file header
 108          *
 109          * @return      void
 110          */
 111         public function flushFileHeader () {
 112                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 113
 114                 // Put all informations together
 115                 $header = sprintf('%s%s%s%s%s%s',
 116                         // Magic
 117                         self::STACK_MAGIC,
 118
 119                         // Separator magic<->count
 120                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 121
 122                         // Total entries (will be zero) and pad it to 20 chars
 123                         str_pad($this->dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 124
 125                         // Separator count<->seek position
 126                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 127
 128                         // Position (will be zero)
 129                         str_pad($this->dec2hex($this->getIteratorInstance()->getSeekPosition(), 2), BaseBinaryFile::LENGTH_POSITION, '0', STR_PAD_LEFT),
 130
 131                         // Separator position<->entries
 132                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 133                 );
 134
 135                 // Write it to disk (header is always at seek position 0)
 136                 $this->getIteratorInstance()->writeData(0, $header, FALSE);
 137
 138                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 139         }
 140
 141         /**
 142          * Initializes this file-based stack.
 143          *
 144          * @param       $fileName       File name of this stack
 145          * @param       $type           Type of this stack (e.g. url_source for URL sources)
 146          * @return      void
 147          * @todo        Currently the stack file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole stack file.
 148          */
 149         protected function initFileStack ($fileName, $type) {
 150                 // Get a stack file instance
 151                 $fileInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileName, $this));
 152
 153                 // Get iterator instance
 154                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 155
 156                 // Is the instance implementing the right interface?
 157                 assert($iteratorInstance instanceof SeekableWritableFileIterator);
 158
 159                 // Set iterator here
 160                 $this->setIteratorInstance($iteratorInstance);
 161
 162                 // Calculate header size
 163                 $this->getIteratorInstance()->setHeaderSize(
 164                         strlen(self::STACK_MAGIC) +
 165                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 166                         BaseBinaryFile::LENGTH_COUNT +
 167                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 168                         BaseBinaryFile::LENGTH_POSITION +
 169                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 170                 );
 171
 172                 // Init counters and gaps array
 173                 $this->getIteratorInstance()->initCountersGapsArray();
 174
 175                 // Is the file's header initialized?
 176                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 177                         // No, then create it (which may pre-allocate the stack)
 178                         $this->getIteratorInstance()->createFileHeader();
 179
 180                         // And pre-allocate a bit
 181                         $this->getIteratorInstance()->preAllocateFile('file_stack');
 182                 } // END - if
 183
 184                 // Load the file header
 185                 $this->readFileHeader();
 186
 187                 // Count all entries in file
 188                 $this->getIteratorInstance()->analyzeFile();
 189
 190                 /*
 191                  * Get stack index instance. This can be used for faster
 192                  * "defragmentation" and startup.
 193                  */
 194                 $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileName, $type);
 195
 196                 // And set it here
 197                 $this->setIndexInstance($indexInstance);
 198         }
 199
 200         /**
 201          * Adds a value to given stack
 202          *
 203          * @param       $stackerName    Name of the stack
 204          * @param       $value                  Value to add to this stacker
 205          * @return      void
 206          * @throws      FullStackerException    If the stack is full
 207          */
 208         protected function addValue ($stackerName, $value) {
 209                 // Do some tests
 210                 if ($this->isStackFull($stackerName)) {
 211                         // Stacker is full
 212                         throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
 213                 } // END - if
 214
 215                 // Now add the value to the stack
 216                 $this->partialStub('stackerName=' . $stackerName . ',value[]=' . gettype($value));
 217         }
 218
 219         /**
 220          * Get last value from named stacker
 221          *
 222          * @param       $stackerName    Name of the stack
 223          * @return      $value                  Value of last added value
 224          * @throws      EmptyStackerException   If the stack is empty
 225          */
 226         protected function getLastValue ($stackerName) {
 227                 // Is the stack not yet initialized or full?
 228                 if ($this->isStackEmpty($stackerName)) {
 229                         // Throw an exception
 230                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 231                 } // END - if
 232
 233                 // Now get the last value
 234                 $this->partialStub('stackerName=' . $stackerName);
 235                 $value = NULL;
 236
 237                 // Return it
 238                 return $value;
 239         }
 240
 241         /**
 242          * Get first value from named stacker
 243          *
 244          * @param       $stackerName    Name of the stack
 245          * @return      $value                  Value of last added value
 246          * @throws      EmptyStackerException   If the stack is empty
 247          */
 248         protected function getFirstValue ($stackerName) {
 249                 // Is the stack not yet initialized or full?
 250                 if ($this->isStackEmpty($stackerName)) {
 251                         // Throw an exception
 252                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 253                 } // END - if
 254
 255                 // Now get the first value
 256                 $this->partialStub('stackerName=' . $stackerName);
 257                 $value = NULL;
 258
 259                 // Return it
 260                 return $value;
 261         }
 262
 263         /**
 264          * "Pops" last entry from stack
 265          *
 266          * @param       $stackerName    Name of the stack
 267          * @return      $value                  Value "poped" from array
 268          * @throws      EmptyStackerException   If the stack is empty
 269          */
 270         protected function popLast ($stackerName) {
 271                 // Is the stack not yet initialized or full?
 272                 if ($this->isStackEmpty($stackerName)) {
 273                         // Throw an exception
 274                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 275                 } // END - if
 276
 277                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 278                 $this->partialStub('stackerName=' . $stackerName);
 279                 return NULL;
 280         }
 281
 282         /**
 283          * "Pops" first entry from stack
 284          *
 285          * @param       $stackerName    Name of the stack
 286          * @return      $value                  Value "shifted" from array
 287          * @throws      EmptyStackerException   If the named stacker is empty
 288          */
 289         protected function popFirst ($stackerName) {
 290                 // Is the stack not yet initialized or full?
 291                 if ($this->isStackEmpty($stackerName)) {
 292                         // Throw an exception
 293                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 294                 } // END - if
 295
 296                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 297                 $this->partialStub('stackerName=' . $stackerName);
 298                 return NULL;
 299         }
 300
 301         /**
 302          * Checks whether the given stack is full
 303          *
 304          * @param       $stackerName    Name of the stack
 305          * @return      $isFull                 Whether the stack is full
 306          */
 307         protected function isStackFull ($stackerName) {
 308                 // File-based stacks will only run full if the disk space is low.
 309                 // @TODO Please implement this, returning FALSE
 310                 $isFull = FALSE;
 311
 312                 // Return result
 313                 return $isFull;
 314         }
 315
 316         /**
 317          * Checks whether the given stack is empty
 318          *
 319          * @param       $stackerName            Name of the stack
 320          * @return      $isEmpty                        Whether the stack is empty
 321          * @throws      NoStackerException      If given stack is missing
 322          */
 323         public function isStackEmpty ($stackerName) {
 324                 // So, is the stack empty?
 325                 $isEmpty = (($this->getStackCount($stackerName)) == 0);
 326
 327                 // Return result
 328                 return $isEmpty;
 329         }
 330
 331         /**
 332          * Initializes given stacker
 333          *
 334          * @param       $stackerName    Name of the stack
 335          * @param       $forceReInit    Force re-initialization
 336          * @return      void
 337          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 338          */
 339         public function initStack ($stackerName, $forceReInit = FALSE) {
 340                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 341         }
 342
 343         /**
 344          * Initializes all stacks
 345          *
 346          * @return      void
 347          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 348          */
 349         public function initStacks (array $stacks, $forceReInit = FALSE) {
 350                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 351         }
 352
 353         /**
 354          * Checks whether the given stack is initialized (set in array $stackers)
 355          *
 356          * @param       $stackerName    Name of the stack
 357          * @return      $isInitialized  Whether the stack is initialized
 358          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 359          */
 360         public function isStackInitialized ($stackerName) {
 361                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 362         }
 363
 364         /**
 365          * Close a file source and set it's instance to null and the file name
 366          * to empty.
 367          *
 368          * @return      void
 369          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 370          */
 371         public function closeFile () {
 372                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 373         }
 374
 375         /**
 376          * Determines whether the EOF has been reached
 377          *
 378          * @return      $isEndOfFileReached             Whether the EOF has been reached
 379          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 380          */
 381         public function isEndOfFileReached () {
 382                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 383         }
 384
 385         /**
 386          * Getter for file name
 387          *
 388          * @return      $fileName       The current file name
 389          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 390          */
 391         public function getFileName () {
 392                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 393         }
 394
 395         /**
 396          * Getter for size of given stack (array count)
 397          *
 398          * @param       $stackerName    Name of the stack
 399          * @return      $count                  Size of stack (array count)
 400          */
 401         public function getStackCount ($stackerName) {
 402                 // Now, simply return the found count value, this must be up-to-date then!
 403                 return $this->getIteratorInstance()->getCounter();
 404         }
 405
 406         /**
 407          * Calculates minimum length for one entry/block
 408          *
 409          * @return      $length         Minimum length for one entry/block
 410          */
 411         public function calculateMinimumBlockLength () {
 412                 // Calulcate it
 413                 $length = self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_NAME)) + BaseBinaryFile::LENGTH_NAME + 1 + strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 414
 415                 // Return it
 416                 return $length;
 417         }
 418
 419         /**
 420          * Initializes counter for valid entries, arrays for damaged entries and
 421          * an array for gap seek positions. If you call this method on your own,
 422          * please re-analyze the file structure. So you are better to call
 423          * analyzeFile() instead of this method.
 424          *
 425          * @return      void
 426          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 427          */
 428         public function initCountersGapsArray () {
 429                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 430         }
 431
 432         /**
 433          * Getter for header size
 434          *
 435          * @return      $totalEntries   Size of file header
 436          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 437          */
 438         public final function getHeaderSize () {
 439                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 440         }
 441
 442         /**
 443          * Setter for header size
 444          *
 445          * @param       $headerSize             Size of file header
 446          * @return      void
 447          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 448          */
 449         public final function setHeaderSize ($headerSize) {
 450                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 451         }
 452
 453         /**
 454          * Getter for header array
 455          *
 456          * @return      $totalEntries   Size of file header
 457          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 458          */
 459         public final function getHeader () {
 460                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 461         }
 462
 463         /**
 464          * Setter for header
 465          *
 466          * @param       $header         Array for a file header
 467          * @return      void
 468          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 469          */
 470         public final function setHeader (array $header) {
 471                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 472         }
 473
 474         /**
 475          * Updates seekPosition attribute from file to avoid to much access on file.
 476          *
 477          * @return      void
 478          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 479          */
 480         public function updateSeekPosition () {
 481                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 482         }
 483
 484         /**
 485          * Getter for total entries
 486          *
 487          * @return      $totalEntries   Total entries in this file
 488          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 489          */
 490         public final function getCounter () {
 491                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 492         }
 493
 494         /**
 495          * "Getter" for file size
 496          *
 497          * @return      $fileSize       Size of currently loaded file
 498          */
 499         public function getFileSize () {
 500                 // Call iterator's method
 501                 return $this->getIteratorInstance()->getFileSize();
 502         }
 503 }
 504
 505 // [EOF]
 506 ?>