*/
private $fileName = '';
+ /**
+ * Back-buffer
+ */
+ private $backBuffer = '';
+
+ /**
+ * Currently loaded block (will be returned by current())
+ */
+ private $currentBlock = '';
+
/**
* Protected constructor
*
* @param $className Name of the class
- * @return void
+y * @return void
*/
protected function __construct ($className) {
// Call parent constructor
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
*
$this->setPointerInstance($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
* @return $seekPosition Current seek position
*/
public function determineSeekPosition () {
+ // Call pointer instance
return $this->getPointerInstance()->determineSeekPosition();
}
* @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);
}
* @todo Handle seekStatus
*/
public function size () {
+ // Call pointer instance
return $this->getPointerInstance()->size();
}
* @throws InvalidResourceException If there is being set
*/
public function readFromFile () {
+ // Call pointer instance
return $this->getPointerInstance()->readFromFile();
}
* @return $data Data read from file
*/
public function read ($bytes) {
+ // Call pointer instance
return $this->getPointerInstance()->read($bytes);
}
* an invalid file resource
*/
public function writeToFile ($dataStream) {
+ // Call pointer instance
return $this->getPointerInstance()->writeToFile($dataStream);
}
* @return $status Status of this operation
*/
public function rewind () {
+ // Call pointer instance
return $this->getPointerInstance()->rewind();
}
* @return $isEndOfFileReached Whether the EOF has been reached
*/
public final function isEndOfFileReached () {
+ // Call pointer instance
return $this->getPointerInstance()->isEndOfFileReached();
}
$this->next();
// Get current entry
- $current = $this->current();
+ $current = $this->getCurrentBlock();
- // Simply output it
- self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] current=%s', __METHOD__, __LINE__, print_r($current, TRUE)));
+ // Debug message
+ /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] current()=%s', __METHOD__, __LINE__, strlen($current)));
} // END - while
//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
}
+
+ /**
+ * Advances to next "block" of bytes
+ *
+ * @return void
+ * @todo This method will load large but empty files in a whole
+ */
+ public function next () {
+ // Is there nothing to read?
+ if (!$this->valid()) {
+ // Nothing to read
+ return;
+ } // END - if
+
+ // Make sure the block instance is set
+ assert($this->getBlockInstance() instanceof Block);
+
+ // First calculate minimum block length
+ $length = $this->getBlockInstance()->calculateMinimumBlockLength();
+
+ // Short be more than zero!
+ assert($length > 0);
+
+ // Wait until a entry/block separator has been found
+ $data = $this->getBackBuffer();
+ while ((!$this->isEndOfFileReached()) && (!self::isBlockSeparatorFound($data))) {
+ // Then read the block
+ $data .= $this->read($length);
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('data()=' . strlen($data));
+ } // END - if
+
+ // EOF reached?
+ if ($this->isEndOfFileReached()) {
+ // Set whole data as current 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(self::getBlockSeparator(), $data);
+
+ // This array must contain two elements
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('dataArray=' . print_r($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]
projects / core.git / blobdiff