inc/classes/main/file_directories/class_BaseFile.php

   1 <?php
   2 /**
   3  * A general file class
   4  *
   5  * @author              Roland Haeder <webmaster@ship-simu.org>
   6  * @version             0.0.0
   7  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2012 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 BaseFile extends BaseFrameworkSystem {
  25         /**
  26          * The current file we are working in
  27          */
  28         private $fileName = '';
  29
  30         /**
  31          * Back-buffer
  32          */
  33         private $backBuffer = '';
  34
  35         /**
  36          * Currently loaded block (will be returned by current())
  37          */
  38         private $currentBlock = '';
  39
  40         /**
  41          * Protected constructor
  42          *
  43          * @param       $className      Name of the class
  44 y        * @return      void
  45          */
  46         protected function __construct ($className) {
  47                 // Call parent constructor
  48                 parent::__construct($className);
  49
  50                 // Init counters and gaps array
  51                 $this->initCountersGapsArray();
  52         }
  53
  54         /**
  55          * Destructor for cleaning purposes, etc
  56          *
  57          * @return      void
  58          */
  59         public final function __destruct() {
  60                 // Try to close a file
  61                 $this->closeFile();
  62
  63                 // Call the parent destructor
  64                 parent::__destruct();
  65         }
  66
  67         /**
  68          * Getter for the file pointer
  69          *
  70          * @return      $filePointer    The file pointer which shall be a valid file resource
  71          * @throws      UnsupportedOperationException   If this method is called
  72          */
  73         public final function getPointer () {
  74                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
  75         }
  76
  77         /**
  78          * Setter for file name
  79          *
  80          * @param       $fileName       The new file name
  81          * @return      void
  82          */
  83         protected final function setFileName ($fileName) {
  84                 $fileName = (string) $fileName;
  85                 $this->fileName = $fileName;
  86         }
  87
  88         /**
  89          * Getter for file name
  90          *
  91          * @return      $fileName       The current file name
  92          */
  93         public final function getFileName () {
  94                 return $this->fileName;
  95         }
  96
  97         /**
  98          * Initializes the back-buffer by setting it to an empty string.
  99          *
 100          * @return      void
 101          */
 102         private function initBackBuffer () {
 103                 // Simply call the setter
 104                 $this->setBackBuffer('');
 105         }
 106
 107         /**
 108          * Setter for backBuffer field
 109          *
 110          * @param       $backBuffer             Characters to "store" in back-buffer
 111          * @return      void
 112          */
 113         private function setBackBuffer ($backBuffer) {
 114                 // Cast to string (so no arrays or objects)
 115                 $backBuffer = (string) $backBuffer;
 116
 117                 // ... and set it
 118                 $this->backBuffer = $backBuffer;
 119         }
 120
 121         /**
 122          * Getter for backBuffer field
 123          *
 124          * @return      $backBuffer             Characters "stored" in back-buffer
 125          */
 126         private function getBackBuffer () {
 127                 return $this->backBuffer;
 128         }
 129
 130         /**
 131          * Setter for currentBlock field
 132          *
 133          * @param       $currentBlock           Characters to set a currently loaded block
 134          * @return      void
 135          */
 136         private function setCurrentBlock ($currentBlock) {
 137                 // Cast to string (so no arrays or objects)
 138                 $currentBlock = (string) $currentBlock;
 139
 140                 // ... and set it
 141                 $this->currentBlock = $currentBlock;
 142         }
 143
 144         /**
 145          * Gets currently read data
 146          *
 147          * @return      $current        Currently read data
 148          */
 149         public function getCurrentBlock () {
 150                 // Return it
 151                 return $this->currentBlock;
 152         }
 153
 154         /**
 155          * Initializes this file class
 156          *
 157          * @param       $fileName       Name of this abstract file
 158          * @return      void
 159          */
 160         protected function initFile ($fileName) {
 161                 // Get a file i/o pointer instance
 162                 $pointerInstance = ObjectFactory::createObjectByConfiguredName('file_raw_input_output_class', array($fileName));
 163
 164                 // ... and set it here
 165                 $this->setPointerInstance($pointerInstance);
 166         }
 167
 168         /**
 169          * Writes data at given position
 170          *
 171          * @param       $seekPosition   Seek position
 172          * @param       $data                   Data to be written
 173          * @param       $flushHeader    Whether to flush the header (default: flush)
 174          * @return      void
 175          */
 176         protected function writeData ($seekPosition, $data, $flushHeader = TRUE) {
 177                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data()=%s - CALLED!', __METHOD__, __LINE__, $seekPosition, strlen($data)));
 178
 179                 // Write data at given position
 180                 $this->getPointerInstance()->writeAtPosition($seekPosition, $data);
 181
 182                 // Update seek position
 183                 $this->updateSeekPosition();
 184
 185                 // Flush the header?
 186                 if ($flushHeader === TRUE) {
 187                         // Flush header
 188                         $this->flushFileHeader();
 189
 190                         // Seek to old position
 191                         $this->seekToOldPosition();
 192                 } // END - if
 193
 194                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 195         }
 196
 197         /**
 198          * Checks whether the file header is initialized
 199          *
 200          * @return      $isInitialized  Whether the file header is initialized
 201          */
 202         public function isFileHeaderInitialized () {
 203                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 204
 205                 // Default is not initialized
 206                 $isInitialized = FALSE;
 207
 208                 // Is the file initialized?
 209                 if ($this->isFileInitialized()) {
 210                         // Some bytes has been written, so rewind to start of it.
 211                         $rewindStatus = $this->getIteratorInstance()->rewind();
 212                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] rewindStatus=%s', __METHOD__, __LINE__, $rewindStatus));
 213
 214                         // Is the rewind() call successfull?
 215                         if ($rewindStatus != 1) {
 216                                 // Something bad happened
 217                                 self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Could not rewind().', __METHOD__, __LINE__));
 218                         } // END - if
 219
 220                         // Read file header
 221                         $this->readFileHeader()
 222
 223                         // The above method does already check the header
 224                         $isInitialized = TRUE;
 225                 } // END - if
 226
 227                 // Return result
 228                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
 229                 return $isInitialized;
 230         }
 231
 232         /**
 233          * Checks whether the assigned file has been initialized
 234          *
 235          * @return      $isInitialized          Whether the file's size is zero
 236          */
 237         public function isFileInitialized () {
 238                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 239
 240                 // Get it from iterator which holds the pointer instance. If FALSE is returned
 241                 $fileSize = $this->size();
 242                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] fileSize=%s', __METHOD__, __LINE__, $fileSize));
 243
 244                 /*
 245                  * The returned file size should not be FALSE or NULL as this means
 246                  * that the pointer class does not work correctly.
 247                  */
 248                 assert(is_int($fileSize));
 249
 250                 // Is more than 0 returned?
 251                 $isInitialized = ($fileSize > 0);
 252
 253                 // Return result
 254                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
 255                 return $isInitialized;
 256         }
 257
 258         /**
 259          * Creates the assigned file
 260          *
 261          * @return      void
 262          */
 263         public function createFileHeader () {
 264                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 265
 266                 // The file's header should not be initialized here
 267                 assert(!$this->isFileHeaderInitialized());
 268
 269                 // Simple flush file header which will create it.
 270                 $this->flushFileHeader();
 271
 272                 // Rewind seek position (to beginning of file) and update/flush file header
 273                 $this->rewineUpdateSeekPosition();
 274
 275                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!!', __METHOD__, __LINE__));
 276         }
 277
 278         /**
 279          * Pre-allocates file (if enabled) with some space for later faster write access.
 280          *
 281          * @param       $type   Type of the file
 282          * @return      void
 283          */
 284         public function preAllocateFile ($type) {
 285                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 286
 287                 // Is it enabled?
 288                 if ($this->getConfigInstance()->getConfigEntry($type . '_pre_allocate_enabled') != 'Y') {
 289                         // Not enabled
 290                         self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Not pre-allocating file.', __METHOD__, __LINE__));
 291
 292                         // Don't continue here.
 293                         return;
 294                 } // END - if
 295
 296                 // Message to user
 297                 self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Pre-allocating file ...', __METHOD__, __LINE__));
 298
 299                 // Calculate minimum length for one entry
 300                 $minLengthEntry = $this->getBlockInstance()->calculateMinimumBlockLength();
 301                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] minLengthEntry=%s', __METHOD__, __LINE__, $minLengthEntry));
 302
 303                 // Calulcate seek position
 304                 $seekPosition = $minLengthEntry * $this->getConfigInstance()->getConfigEntry($type . '_pre_allocate_count');
 305                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
 306
 307                 // Now simply write a NUL there. This will pre-allocate the file.
 308                 $this->writeData($seekPosition, chr(0));
 309
 310                 // Rewind seek position (to beginning of file) and update/flush file header
 311                 $this->rewineUpdateSeekPosition();
 312
 313                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 314         }
 315
 316         /**
 317          * Close a file source and set it's instance to null and the file name
 318          * to empty
 319          *
 320          * @return      void
 321          * @todo        ~10% done?
 322          */
 323         public function closeFile () {
 324                 $this->partialStub('Unfinished method.');
 325
 326                 // Remove file name
 327                 $this->setFileName('');
 328         }
 329
 330         /**
 331          * Determines seek position
 332          *
 333          * @return      $seekPosition   Current seek position
 334          */
 335         public function determineSeekPosition () {
 336                 // Call pointer instance
 337                 return $this->getPointerInstance()->determineSeekPosition();
 338         }
 339
 340         /**
 341          * Seek to given offset (default) or other possibilities as fseek() gives.
 342          *
 343          * @param       $offset         Offset to seek to (or used as "base" for other seeks)
 344          * @param       $whence         Added to offset (default: only use offset to seek to)
 345          * @return      $status         Status of file seek: 0 = success, -1 = failed
 346          */
 347         public function seek ($offset, $whence = SEEK_SET) {
 348                 // Call pointer instance
 349                 return $this->getPointerInstance()->seek($offset, $whence);
 350         }
 351
 352         /**
 353          * Size of this file
 354          *
 355          * @return      $size   Size (in bytes) of file
 356          * @todo        Handle seekStatus
 357          */
 358         public function size () {
 359                 // Call pointer instance
 360                 return $this->getPointerInstance()->size();
 361         }
 362
 363         /**
 364          * Read data a file pointer
 365          *
 366          * @return      mixed   The result of fread()
 367          * @throws      NullPointerException    If the file pointer instance
 368          *                                                                      is not set by setPointer()
 369          * @throws      InvalidResourceException        If there is being set
 370          */
 371         public function readFromFile () {
 372                 // Call pointer instance
 373                 return $this->getPointerInstance()->readFromFile();
 374         }
 375
 376         /**
 377          * Reads given amount of bytes from file.
 378          *
 379          * @param       $bytes  Amount of bytes to read
 380          * @return      $data   Data read from file
 381          */
 382         public function read ($bytes) {
 383                 // Call pointer instance
 384                 return $this->getPointerInstance()->read($bytes);
 385         }
 386
 387         /**
 388          * Write data to a file pointer
 389          *
 390          * @param       $dataStream             The data stream we shall write to the file
 391          * @return      mixed                   Number of writes bytes or FALSE on error
 392          * @throws      NullPointerException    If the file pointer instance
 393          *                                                                      is not set by setPointer()
 394          * @throws      InvalidResourceException        If there is being set
 395          *                                                                                      an invalid file resource
 396          */
 397         public function writeToFile ($dataStream) {
 398                 // Call pointer instance
 399                 return $this->getPointerInstance()->writeToFile($dataStream);
 400         }
 401
 402         /**
 403          * Rewinds to the beginning of the file
 404          *
 405          * @return      $status         Status of this operation
 406          */
 407         public function rewind () {
 408                 // Call pointer instance
 409                 return $this->getPointerInstance()->rewind();
 410         }
 411
 412         /**
 413          * Determines whether the EOF has been reached
 414          *
 415          * @return      $isEndOfFileReached             Whether the EOF has been reached
 416          */
 417         public final function isEndOfFileReached () {
 418                 // Call pointer instance
 419                 return $this->getPointerInstance()->isEndOfFileReached();
 420         }
 421
 422         /**
 423          * Analyzes entries in index file. This will count all found (and valid)
 424          * entries, mark invalid as damaged and count gaps ("fragmentation"). If
 425          * only gaps are found, the file is considered as "virgin" (no entries).
 426          *
 427          * @return      void
 428          */
 429         public function analyzeFile () {
 430                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 431
 432                 // Make sure the file is initialized
 433                 assert($this->isFileInitialized());
 434
 435                 // Init counters and gaps array
 436                 $this->initCountersGapsArray();
 437
 438                 // Output message (as this may take some time)
 439                 self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Analyzing file structure ... (this may take some time)', __METHOD__, __LINE__));
 440
 441                 // First rewind to the begining
 442                 $this->rewind();
 443
 444                 // Then try to load all entries
 445                 while ($this->valid()) {
 446                         // Go to next entry
 447                         $this->next();
 448
 449                         // Get current entry
 450                         $current = $this->getCurrentBlock();
 451
 452                         // Debug message
 453                         /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] current()=%s', __METHOD__, __LINE__, strlen($current)));
 454                 } // END - while
 455
 456                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 457         }
 458
 459         /**
 460          * Advances to next "block" of bytes
 461          *
 462          * @return      void
 463          * @todo        This method will load large but empty files in a whole
 464          */
 465         public function next () {
 466                 // Is there nothing to read?
 467                 if (!$this->valid()) {
 468                         // Nothing to read
 469                         return;
 470                 } // END - if
 471
 472                 // Make sure the block instance is set
 473                 assert($this->getBlockInstance() instanceof CalculatableBlock);
 474
 475                 // First calculate minimum block length
 476                 $length = $this->getBlockInstance()->calculateMinimumBlockLength();
 477
 478                 // Short be more than zero!
 479                 assert($length > 0);
 480
 481                 // Wait until a entry/block separator has been found
 482                 $data = $this->getBackBuffer();
 483                 while ((!$this->isEndOfFileReached()) && (!self::isBlockSeparatorFound($data))) {
 484                         // Then read the block
 485                         $data .= $this->read($length);
 486                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('data()=' . strlen($data));
 487                 } // END - if
 488
 489                 // EOF reached?
 490                 if ($this->isEndOfFileReached()) {
 491                         // Set whole data as current block
 492                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('Calling setCurrentBlock(' . strlen($data) . ') ...');
 493                         $this->setCurrentBlock($data);
 494
 495                         // Then abort here silently
 496                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('EOF reached.');
 497                         return;
 498                 } // END - if
 499
 500                 /*
 501                  * Init back-buffer which is the data that has been found beyond the
 502                  * separator.
 503                  */
 504                 $this->initBackBuffer();
 505
 506                 // Separate data
 507                 $dataArray = explode(self::getBlockSeparator(), $data);
 508
 509                 // This array must contain two elements
 510                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('dataArray=' . print_r($dataArray, TRUE));
 511                 assert(count($dataArray) == 2);
 512
 513                 // Left part is the actual block, right one the back-buffer data
 514                 $this->setCurrentBlock($dataArray[0]);
 515                 $this->setBackBuffer($dataArray[1]);
 516         }
 517
 518         /**
 519          * Checks wether the current entry is valid (not at the end of the file).
 520          * This method will return TRUE if an emptied (nulled) entry has been found.
 521          *
 522          * @return      $isValid        Whether the next entry is valid
 523          */
 524         public function valid () {
 525                 // Make sure the block instance is set
 526                 assert($this->getBlockInstance() instanceof CalculatableBlock);
 527
 528                 // First calculate minimum block length
 529                 $length = $this->getBlockInstance()->calculateMinimumBlockLength();
 530
 531                 // Short be more than zero!
 532                 assert($length > 0);
 533
 534                 // Get current seek position
 535                 $seekPosition = $this->key();
 536
 537                 // Then try to read it
 538                 $data = $this->read($length);
 539
 540                 // If some bytes could be read, all is fine
 541                 $isValid = ((is_string($data)) && (strlen($data) > 0));
 542
 543                 // Get header size
 544                 $headerSize = $this->getBlockInstance()->getHeaderSize();
 545
 546                 // Is the seek position at or beyond the header?
 547                 if ($seekPosition >= $headerSize) {
 548                         // Seek back to old position
 549                         $this->seek($seekPosition);
 550                 } else {
 551                         // Seek directly behind the header
 552                         $this->seek($headerSize);
 553                 }
 554
 555                 // Return result
 556                 return $isValid;
 557         }
 558
 559         /**
 560          * Gets current seek position ("key").
 561          *
 562          * @return      $key    Current key in iteration
 563          */
 564         public function key () {
 565                 // Call pointer instance
 566                 return $this->getPointerInstance()->determineSeekPosition();
 567         }
 568
 569         /**
 570          * Reads the file header
 571          *
 572          * @return      void
 573          */
 574         public function readFileHeader () {
 575                 // Call block instance
 576                 $this->getBlockInstance()->readFileHeader()
 577         }
 578
 579         /**
 580          * Flushes the file header
 581          *
 582          * @return      void
 583          */
 584         public function flushFileHeader () {
 585                 // Call block instance
 586                 $this->getBlockInstance()->flushFileHeader()
 587         }
 588 }
 589
 590 // [EOF]
 591 ?>