X-Git-Url: https://git.mxchange.org/?p=core.git;a=blobdiff_plain;f=inc%2Fclasses%2Fmain%2Ffile_directories%2Fclass_BaseFile.php;h=0d1bb418ea9be169b0357cf5b607718cbaaa46af;hp=1d3dac19e1e0016769992519d5088cc532867e72;hb=c77663981dbaefb7d8ff039967509aa1204ee556;hpb=2fec9045a98aa767876276a0ef934b8a3eccc5fa

diff --git a/inc/classes/main/file_directories/class_BaseFile.php b/inc/classes/main/file_directories/class_BaseFile.php
index 1d3dac19..0d1bb418 100644
--- a/inc/classes/main/file_directories/class_BaseFile.php
+++ b/inc/classes/main/file_directories/class_BaseFile.php
@@ -4,7 +4,7 @@
  *
  * @author		Roland Haeder <webmaster@ship-simu.org>
  * @version		0.0.0
- * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2012 Core Developer Team
+ * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2014 Core Developer Team
  * @license		GNU GPL 3.0 or any newer version
  * @link		http://www.ship-simu.org
  *
@@ -22,113 +22,25 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 class BaseFile extends BaseFrameworkSystem {
-	/**
-	 * Separator for header data
-	 */
-	const SEPARATOR_HEADER_DATA = 0x01;
-
-	/**
-	 * Separator header->entries
-	 */
-	const SEPARATOR_HEADER_ENTRIES = 0x02;
-
-	/**
-	 * Separator hash->name
-	 */
-	const SEPARATOR_HASH_NAME = 0x03;
-
-	/**
-	 * Separator entry->entry
-	 */
-	const SEPARATOR_ENTRIES = 0x04;
-
-	/**
-	 * Separator type->position
-	 */
-	const SEPARATOR_TYPE_POSITION = 0x05;
-
-	/**
-	 * Length of count
-	 */
-	const LENGTH_COUNT = 20;
-
-	/**
-	 * Length of position
-	 */
-	const LENGTH_POSITION = 20;
-
-	/**
-	 * Length of name
-	 */
-	const LENGTH_NAME = 10;
-
-	/**
-	 * Maximum length of entry type
-	 */
-	const LENGTH_TYPE = 20;
-
-	/**
-	 * Length of output from hash()
-	 */
-	private static $hashLength = NULL;
-
 	/**
 	 * Counter for total entries
 	 */
 	private $totalEntries = 0;
 
-	/**
-	 * Current seek position
-	 */
-	private $seekPosition = 0;
-
-	/**
-	 * Size of header
-	 */
-	private $headerSize = 0;
-
-	/**
-	 * File header
-	 */
-	private $header = array();
-
-	/**
-	 * Seek positions for gaps ("fragmentation")
-	 */
-	private $gaps = array();
-
-	/**
-	 * Seek positions for damaged entries (e.g. mismatching hash sum, ...)
-	 */
-	private $damagedEntries = array();
-
 	/**
 	 * The current file we are working in
 	 */
 	private $fileName = '';
 
-	/**
-	 * Back-buffer
-	 */
-	private $backBuffer = '';
-
-	/**
-	 * Currently loaded block (will be returned by current())
-	 */
-	private $currentBlock = '';
-
 	/**
 	 * Protected constructor
 	 *
 	 * @param	$className	Name of the class
-y	 * @return	void
+	 * @return	void
 	 */
 	protected function __construct ($className) {
 		// Call parent constructor
 		parent::__construct($className);
-
-		// Init counters and gaps array
-		$this->initCountersGapsArray();
 	}
 
 	/**
@@ -145,21 +57,13 @@ y	 * @return	void
 	}
 
 	/**
-	 * Initializes counter for valid entries, arrays for damaged entries and
-	 * an array for gap seek positions. If you call this method on your own,
-	 * please re-analyze the file structure. So you are better to call
-	 * analyzeFile() instead of this method.
+	 * "Getter" for abstracted file size
 	 *
-	 * @return	void
+	 * @return	$fileSize	Size of abstracted file
 	 */
-	protected function initCountersGapsArray () {
-		// Init counter and seek position
-		$this->setCounter(0);
-		$this->setSeekPosition(0);
-
-		// Init arrays
-		$this->gaps = array();
-		$this->damagedEntries = array();
+	public function getFileSize () {
+		// Call pointer instanze
+		return $this->getPointerInstance()->getFileSize();
 	}
 
 	/**
@@ -167,7 +71,7 @@ y	 * @return	void
 	 *
 	 * @return	$totalEntries	Total entries in this file
 	 */
-	protected final function getCounter () {
+	public final function getCounter () {
 		// Get it
 		return $this->totalEntries;
 	}
@@ -193,139 +97,6 @@ y	 * @return	void
 		$this->totalEntries++;
 	}
 
-	/**
-	 * Getter for header size
-	 *
-	 * @return	$totalEntries	Size of file header
-	 */
-	public final function getHeaderSize () {
-		// Get it
-		return $this->headerSize;
-	}
-
-	/**
-	 * Setter for header size
-	 *
-	 * @param	$headerSize		Size of file header
-	 * @return	void
-	 */
-	protected final function setHeaderSize ($headerSize) {
-		// Set it
-		$this->headerSize = $headerSize;
-	}
-
-	/**
-	 * Getter for header array
-	 *
-	 * @return	$totalEntries	Size of file header
-	 */
-	protected final function getHeade () {
-		// Get it
-		return $this->header;
-	}
-
-	/**
-	 * Setter for header
-	 *
-	 * @param	$header		Array for a file header
-	 * @return	void
-	 */
-	protected final function setHeader (array $header) {
-		// Set it
-		$this->header = $header;
-	}
-
-	/**
-	 * Getter for seek position
-	 *
-	 * @return	$seekPosition	Current seek position (stored here in object)
-	 */
-	protected final function getSeekPosition () {
-		// Get it
-		return $this->seekPosition;
-	}
-
-	/**
-	 * Setter for seek position
-	 *
-	 * @param	$seekPosition	Current seek position (stored here in object)
-	 * @return	void
-	 */
-	protected final function setSeekPosition ($seekPosition) {
-		// And set it
-		$this->seekPosition = $seekPosition;
-	}
-
-	/**
-	 * Updates seekPosition attribute from file to avoid to much access on file.
-	 *
-	 * @return	void
-	 */
-	protected function updateSeekPosition () {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// Get key (= seek position)
-		$seekPosition = $this->getIteratorInstance()->key();
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Setting seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
-
-		// And set it here
-		$this->setSeekPosition($seekPosition);
-
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
-	}
-
-	/**
-	 * Seeks to beginning of file, updates seek position in this object and
-	 * flushes the header.
-	 *
-	 * @return	void
-	 */
-	protected function rewineUpdateSeekPosition () {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// flushFileHeader must be callable
-		assert(is_callable(array($this, 'flushFileHeader')));
-
-		// Seek to beginning of file
-		$this->getIteratorInstance()->rewind();
-
-		// And update seek position ...
-		$this->updateSeekPosition();
-
-		// ... to write it back into the file
-		$this->flushFileHeader();
-
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!!', __METHOD__, __LINE__));
-	}
-
-	/**
-	 * Seeks to old position
-	 *
-	 * @return	void
-	 */
-	protected function seekToOldPosition () {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// Seek to currently ("old") saved position
-		$this->getIteratorInstance()->seek($this->getSeekPosition());
-
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!!', __METHOD__, __LINE__));
-	}
-
-	/**
-	 * Checks whether the block separator has been found
-	 *
-	 * @param	$str		String to look in
-	 * @return	$isFound	Whether the block separator has been found
-	 */
-	public static function isBlockSeparatorFound ($str) {
-		// Determine it
-		$isFound = (strpos($str, chr(self::SEPARATOR_ENTRIES)) !== FALSE);
-
-		// Return result
-		return $isFound;
-	}
-
 	/**
 	 * Getter for the file pointer
 	 *
@@ -356,225 +127,6 @@ y	 * @return	void
 		return $this->fileName;
 	}
 
-	/**
-	 * Initializes the back-buffer by setting it to an empty string.
-	 *
-	 * @return	void
-	 */
-	private function initBackBuffer () {
-		// Simply call the setter
-		$this->setBackBuffer('');
-	}
-
-	/**
-	 * Setter for backBuffer field
-	 *
-	 * @param	$backBuffer		Characters to "store" in back-buffer
-	 * @return	void
-	 */
-	private function setBackBuffer ($backBuffer) {
-		// Cast to string (so no arrays or objects)
-		$backBuffer = (string) $backBuffer;
-
-		// ... and set it
-		$this->backBuffer = $backBuffer;
-	}
-
-	/**
-	 * Getter for backBuffer field
-	 *
-	 * @return	$backBuffer		Characters "stored" in back-buffer
-	 */
-	private function getBackBuffer () {
-		return $this->backBuffer;
-	}
-
-	/**
-	 * Setter for currentBlock field
-	 *
-	 * @param	$currentBlock		Characters to set a currently loaded block
-	 * @return	void
-	 */
-	private function setCurrentBlock ($currentBlock) {
-		// Cast to string (so no arrays or objects)
-		$currentBlock = (string) $currentBlock;
-
-		// ... and set it
-		$this->currentBlock = $currentBlock;
-	}
-
-	/**
-	 * Gets currently read data
-	 *
-	 * @return	$current	Currently read data
-	 */
-	public function getCurrentBlock () {
-		// Return it
-		return $this->currentBlock;
-	}
-
-	/**
-	 * Initializes this file class
-	 *
-	 * @param	$fileName	Name of this abstract file
-	 * @return	void
-	 */
-	protected function initFile ($fileName) {
-		// Get a file i/o pointer instance
-		$pointerInstance = ObjectFactory::createObjectByConfiguredName('file_raw_input_output_class', array($fileName));
-
-		// ... and set it here
-		$this->setPointerInstance($pointerInstance);
-	}
-
-	/**
-	 * Writes data at given position
-	 *
-	 * @param	$seekPosition	Seek position
-	 * @param	$data			Data to be written
-	 * @param	$flushHeader	Whether to flush the header (default: flush)
-	 * @return	void
-	 */
-	protected function writeData ($seekPosition, $data, $flushHeader = TRUE) {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data()=%s - CALLED!', __METHOD__, __LINE__, $seekPosition, strlen($data)));
-
-		// Write data at given position
-		$this->getPointerInstance()->writeAtPosition($seekPosition, $data);
-
-		// Update seek position
-		$this->updateSeekPosition();
-
-		// Flush the header?
-		if ($flushHeader === TRUE) {
-			// Flush header
-			$this->flushFileHeader();
-
-			// Seek to old position
-			$this->seekToOldPosition();
-		} // END - if
-
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
-	}
-
-	/**
-	 * Checks whether the file header is initialized
-	 *
-	 * @return	$isInitialized	Whether the file header is initialized
-	 */
-	public function isFileHeaderInitialized () {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// Default is not initialized
-		$isInitialized = FALSE;
-
-		// Is the file initialized?
-		if ($this->isFileInitialized()) {
-			// Some bytes has been written, so rewind to start of it.
-			$rewindStatus = $this->rewind();
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] rewindStatus=%s', __METHOD__, __LINE__, $rewindStatus));
-
-			// Is the rewind() call successfull?
-			if ($rewindStatus != 1) {
-				// Something bad happened
-				self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Could not rewind().', __METHOD__, __LINE__));
-			} // END - if
-
-			// Read file header
-			$this->readFileHeader();
-
-			// The above method does already check the header
-			$isInitialized = TRUE;
-		} // END - if
-
-		// Return result
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
-		return $isInitialized;
-	}
-
-	/**
-	 * Checks whether the assigned file has been initialized
-	 *
-	 * @return	$isInitialized		Whether the file's size is zero
-	 */
-	public function isFileInitialized () {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// Get it from iterator which holds the pointer instance. If FALSE is returned
-		$fileSize = $this->size();
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] fileSize=%s', __METHOD__, __LINE__, $fileSize));
-
-		/*
-		 * The returned file size should not be FALSE or NULL as this means
-		 * that the pointer class does not work correctly.
-		 */
-		assert(is_int($fileSize));
-
-		// Is more than 0 returned?
-		$isInitialized = ($fileSize > 0);
-
-		// Return result
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
-		return $isInitialized;
-	}
-
-	/**
-	 * Creates the assigned file
-	 *
-	 * @return	void
-	 */
-	public function createFileHeader () {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// The file's header should not be initialized here
-		assert(!$this->isFileHeaderInitialized());
-
-		// Simple flush file header which will create it.
-		$this->flushFileHeader();
-
-		// Rewind seek position (to beginning of file) and update/flush file header
-		$this->rewineUpdateSeekPosition();
-
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!!', __METHOD__, __LINE__));
-	}
-
-	/**
-	 * Pre-allocates file (if enabled) with some space for later faster write access.
-	 *
-	 * @param	$type	Type of the file
-	 * @return	void
-	 */
-	public function preAllocateFile ($type) {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// Is it enabled?
-		if ($this->getConfigInstance()->getConfigEntry($type . '_pre_allocate_enabled') != 'Y') {
-			// Not enabled
-			self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Not pre-allocating file.', __METHOD__, __LINE__));
-
-			// Don't continue here.
-			return;
-		} // END - if
-
-		// Message to user
-		self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Pre-allocating file ...', __METHOD__, __LINE__));
-
-		// Calculate minimum length for one entry
-		$minLengthEntry = $this->getBlockInstance()->calculateMinimumBlockLength();
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] minLengthEntry=%s', __METHOD__, __LINE__, $minLengthEntry));
-
-		// Calulcate seek position
-		$seekPosition = $minLengthEntry * $this->getConfigInstance()->getConfigEntry($type . '_pre_allocate_count');
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
-
-		// Now simply write a NUL there. This will pre-allocate the file.
-		$this->writeData($seekPosition, chr(0));
-
-		// Rewind seek position (to beginning of file) and update/flush file header
-		$this->rewineUpdateSeekPosition();
-
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
-	}
-
 	/**
 	 * Close a file source and set it's instance to null and the file name
 	 * to empty
@@ -589,28 +141,6 @@ y	 * @return	void
 		$this->setFileName('');
 	}
 
-	/**
-	 * Determines seek position
-	 *
-	 * @return	$seekPosition	Current seek position
-	 */
-	public function determineSeekPosition () {
-		// Call pointer instance
-		return $this->getPointerInstance()->determineSeekPosition();
-	}
-
-	/**
-	 * Seek to given offset (default) or other possibilities as fseek() gives.
-	 *
-	 * @param	$offset		Offset to seek to (or used as "base" for other seeks)
-	 * @param	$whence		Added to offset (default: only use offset to seek to)
-	 * @return	$status		Status of file seek: 0 = success, -1 = failed
-	 */
-	public function seek ($offset, $whence = SEEK_SET) {
-		// Call pointer instance
-		return $this->getPointerInstance()->seek($offset, $whence);
-	}
-
 	/**
 	 * Size of this file
 	 *
@@ -635,17 +165,6 @@ y	 * @return	void
 		return $this->getPointerInstance()->readFromFile();
 	}
 
-	/**
-	 * Reads given amount of bytes from file.
-	 *
-	 * @param	$bytes	Amount of bytes to read
-	 * @return	$data	Data read from file
-	 */
-	public function read ($bytes) {
-		// Call pointer instance
-		return $this->getPointerInstance()->read($bytes);
-	}
-
 	/**
 	 * Write data to a file pointer
 	 *
@@ -661,16 +180,6 @@ y	 * @return	void
 		return $this->getPointerInstance()->writeToFile($dataStream);
 	}
 
-	/**
-	 * Rewinds to the beginning of the file
-	 *
-	 * @return	$status 	Status of this operation
-	 */
-	public function rewind () {
-		// Call pointer instance
-		return $this->getPointerInstance()->rewind();
-	}
-
 	/**
 	 * Determines whether the EOF has been reached
 	 *
@@ -680,198 +189,6 @@ y	 * @return	void
 		// Call pointer instance
 		return $this->getPointerInstance()->isEndOfFileReached();
 	}
-
-	/**
-	 * Analyzes entries in index file. This will count all found (and valid)
-	 * entries, mark invalid as damaged and count gaps ("fragmentation"). If
-	 * only gaps are found, the file is considered as "virgin" (no entries).
-	 *
-	 * @return	void
-	 */
-	public function analyzeFile () {
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
-
-		// Make sure the file is initialized
-		assert($this->isFileInitialized());
-
-		// Init counters and gaps array
-		$this->initCountersGapsArray();
-
-		// Output message (as this may take some time)
-		self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Analyzing file structure ... (this may take some time)', __METHOD__, __LINE__));
-
-		// First rewind to the begining
-		$this->rewind();
-
-		// Then try to load all entries
-		while ($this->valid()) {
-			// Go to next entry
-			$this->next();
-
-			// Get current entry
-			$current = $this->getCurrentBlock();
-
-			// Debug message
-			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] current()=%s', __METHOD__, __LINE__, strlen($current)));
-		} // END - while
-
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
-	}
-
-	/**
-	 * Advances to next "block" of bytes
-	 *
-	 * @return	void
-	 */
-	public function next () {
-		// Is there nothing to read?
-		if (!$this->valid()) {
-			// Nothing to read
-			return;
-		} // END - if
-
-		// Make sure the block instance is set
-		assert($this->getBlockInstance() instanceof CalculatableBlock);
-
-		// First calculate minimum block length
-		$length = $this->getBlockInstance()->calculateMinimumBlockLength();
-
-		// Short be more than zero!
-		assert($length > 0);
-
-		// Read possibly back-buffered bytes from previous call of next().
-		$data = $this->getBackBuffer();
-
-		/*
-		 * Read until a entry/block separator has been found. The next read
-		 * "block" may not fit, so this loop will continue until the EOB or EOF
-		 * has been reached whatever comes first.
-		 */
-		while ((!$this->isEndOfFileReached()) && (!self::isBlockSeparatorFound($data))) {
-			// Then read the next possible block
-			$block = $this->read($length);
-
-			// Is it all empty?
-			if (strlen(trim($block)) == 0) {
-				// Mark this block as empty
-				$this->markCurrentBlockAsEmpty($length);
-
-				// Skip to next block
-				continue;
-			} // END - if
-
-			// At this block then
-			$data .= $block;
-
-			// A debug message
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d] data()=%s', __FUNCTION__, __LINE__, strlen($data)));
-		} // END - if
-
-		// EOF reached?
-		if ($this->isEndOfFileReached()) {
-			// Set whole data as current read block
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('Calling setCurrentBlock(' . strlen($data) . ') ...');
-			$this->setCurrentBlock($data);
-
-			// Then abort here silently
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('EOF reached.');
-			return;
-		} // END - if
-
-		/*
-		 * Init back-buffer which is the data that has been found beyond the
-		 * separator.
-		 */
-		$this->initBackBuffer();
-
-		// Separate data
-		$dataArray = explode(chr(self::SEPARATOR_ENTRIES), $data);
-
-		// This array must contain two elements
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('dataArray=' . print_r($dataArray, TRUE));
-		assert(count($dataArray) == 2);
-
-		// Left part is the actual block, right one the back-buffer data
-		$this->setCurrentBlock($dataArray[0]);
-		$this->setBackBuffer($dataArray[1]);
-	}
-
-	/**
-	 * Checks wether the current entry is valid (not at the end of the file).
-	 * This method will return TRUE if an emptied (nulled) entry has been found.
-	 *
-	 * @return	$isValid	Whether the next entry is valid
-	 */
-	public function valid () {
-		// Make sure the block instance is set
-		assert($this->getBlockInstance() instanceof Block);
-
-		// First calculate minimum block length
-		$length = $this->getBlockInstance()->calculateMinimumBlockLength();
-
-		// Short be more than zero!
-		assert($length > 0);
-
-		// Get current seek position
-		$seekPosition = $this->key();
-
-		// Then try to read it
-		$data = $this->read($length);
-
-		// If some bytes could be read, all is fine
-		$isValid = ((is_string($data)) && (strlen($data) > 0));
-
-		// Get header size
-		$headerSize = $this->getBlockInstance()->getHeaderSize();
-
-		// Is the seek position at or beyond the header?
-		if ($seekPosition >= $headerSize) {
-			// Seek back to old position
-			$this->seek($seekPosition);
-		} else {
-			// Seek directly behind the header
-			$this->seek($headerSize);
-		}
-
-		// Return result
-		return $isValid;
-	}
-
-	/**
-	 * Gets current seek position ("key").
-	 *
-	 * @return	$key	Current key in iteration
-	 */
-	public function key () {
-		// Call pointer instance
-		return $this->getPointerInstance()->determineSeekPosition();
-	}
-
-	/**
-	 * Reads the file header
-	 *
-	 * @return	void
-	 */
-	public function readFileHeader () {
-		// Make sure the block instance is set
-		assert($this->getBlockInstance() instanceof Block);
-
-		// Call block instance
-		$this->getBlockInstance()->readFileHeader();
-	}
-
-	/**
-	 * Flushes the file header
-	 *
-	 * @return	void
-	 */
-	public function flushFileHeader () {
-		// Make sure the block instance is set
-		assert($this->getBlockInstance() instanceof Block);
-
-		// Call block instance
-		$this->getBlockInstance()->flushFileHeader();
-	}
 }
 
 // [EOF]