--- /dev/null
+<?php
+/**
+ * A general binary file class
+ *
+ * @author Roland Haeder <webmaster@ship-simu.org>
+ * @version 0.0.0
+ * @copyright Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 Core Developer Team
+ * @license GNU GPL 3.0 or any newer version
+ * @link http://www.ship-simu.org
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+class BaseBinaryFile extends BaseAbstractFile {
+ /**
+ * Separator for header data
+ */
+ const SEPARATOR_HEADER_DATA = 0x01;
+
+ /**
+ * Separator header->entries
+ */
+ const SEPARATOR_HEADER_ENTRIES = 0x02;
+
+ /**
+ * Separator group->hash
+ */
+ const SEPARATOR_GROUP_HASH = 0x03;
+
+ /**
+ * Separator hash->value
+ */
+ const SEPARATOR_HASH_VALUE = 0x04;
+
+ /**
+ * Separator entry->entry
+ */
+ const SEPARATOR_ENTRIES = 0x05;
+
+ /**
+ * Separator type->position
+ */
+ const SEPARATOR_TYPE_POSITION = 0x06;
+
+ /**
+ * Length of count
+ */
+ const LENGTH_COUNT = 20;
+
+ /**
+ * Length of position
+ */
+ const LENGTH_POSITION = 20;
+
+ /**
+ * Length of group
+ */
+ const LENGTH_GROUP = 10;
+
+ /**
+ * Maximum length of entry type
+ */
+ const LENGTH_TYPE = 20;
+
+ //***** Array elements for 'gaps' array *****
+
+ /**
+ * Start of gap
+ */
+ const GAPS_INDEX_START = 'start';
+
+ /**
+ * End of gap
+ */
+ const GAPS_INDEX_END = 'end';
+
+ /**
+ * 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();
+
+ /**
+ * Back-buffer
+ */
+ private $backBuffer = '';
+
+ /**
+ * Currently loaded block (will be returned by current())
+ */
+ private $currentBlock = '';
+
+ /**
+ * Protected constructor
+ *
+ * @param $className Name of the class
+ * @return void
+ */
+ protected function __construct ($className) {
+ // Call parent constructor
+ parent::__construct($className);
+
+ // Init counters and gaps array
+ $this->initCountersGapsArray();
+ }
+
+ /**
+ * Checks whether the abstracted file only contains gaps by counting all
+ * gaps' bytes together and compare it to total length.
+ *
+ * @return $isGapsOnly Whether the abstracted file only contains gaps
+ */
+ private function isFileOnlyGaps () {
+ // First/last gap found?
+ /* Only for debugging
+ if (isset($this->gaps[0])) {
+ // Output first and last gap
+ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] this->gaps[0]=%s,this->gaps[%s]=%s', __METHOD__, __LINE__, print_r($this->gaps[0], TRUE), (count($this->gaps) - 1), print_r($this->gaps[count($this->gaps) - 1], TRUE)));
+ } // END - if
+ */
+
+ // Now count every gap
+ $gapsSize = 0;
+ foreach ($this->gaps as $gap) {
+ // Calculate size of found gap: end-start including both
+ $gapsSize += ($gap[self::GAPS_INDEX_END] - $gap[self::GAPS_INDEX_START]);
+ } // END - if
+
+ // Debug output
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] gapsSize=%s,this->headerSize=%s', __METHOD__, __LINE__, $gapsSize, $this->getHeaderSize()));
+
+ // Total gap size + header size must be same as file size
+ $isGapsOnly = (($this->getHeaderSize() + $gapsSize) == $this->getFileSize());
+
+ // Return status
+ return $isGapsOnly;
+ }
+
+ /**
+ * 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.
+ *
+ * @return void
+ */
+ public function initCountersGapsArray () {
+ // Init counter and seek position
+ $this->setCounter(0);
+ $this->setSeekPosition(0);
+
+ // Init arrays
+ $this->gaps = array();
+ $this->damagedEntries = array();
+ }
+
+ /**
+ * Getter for header size
+ *
+ * @return $totalEntries Size of file header
+ */
+ public final function getHeaderSize () {
+ // Get it
+ return $this->headerSize;
+ }
+
+ /**
+ * Setter for header size
+ *
+ * @param $headerSize Size of file header
+ * @return void
+ */
+ public final function setHeaderSize ($headerSize) {
+ // Set it
+ $this->headerSize = $headerSize;
+ }
+
+ /**
+ * Getter for header array
+ *
+ * @return $totalEntries Size of file header
+ */
+ public final function getHeader () {
+ // Get it
+ return $this->header;
+ }
+
+ /**
+ * Setter for header
+ *
+ * @param $header Array for a file header
+ * @return void
+ */
+ public final function setHeader (array $header) {
+ // Set it
+ $this->header = $header;
+ }
+
+ /**
+ * Getter for seek position
+ *
+ * @return $seekPosition Current seek position (stored here in object)
+ */
+ public 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
+ */
+ public function updateSeekPosition () {
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+
+ // Get key (= seek position)
+ $seekPosition = $this->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 rewindUpdateSeekPosition () {
+ //* 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->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
+ $this->seek($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;
+ }
+
+ /**
+ * 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 $flushHeader Whether to flush the header (default: flush)
+ * @return void
+ */
+ public function writeData ($seekPosition, $data, $flushHeader = TRUE) {
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data()=%d - CALLED!', __METHOD__, __LINE__, $seekPosition, strlen($data)));
+
+ // Write data at given position
+ $this->getPointerInstance()->writeAtPosition($seekPosition, $data);
+
+ // Increment counter
+ $this->incrementCounter();
+
+ // 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__));
+ }
+
+ /**
+ * Marks the currently loaded block as empty (with length of the block)
+ *
+ * @param $length Length of the block
+ * @return void
+ */
+ protected function markCurrentBlockAsEmpty ($length) {
+ // Get current seek position
+ $currentPosition = $this->key();
+
+ // Now add it as gap entry
+ array_push($this->gaps, array(
+ self::GAPS_INDEX_START => ($currentPosition - $length),
+ self::GAPS_INDEX_END => $currentPosition,
+ ));
+ }
+
+ /**
+ * 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->rewindUpdateSeekPosition();
+
+ //* 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->rewindUpdateSeekPosition();
+
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+ }
+
+ /**
+ * 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);
+ }
+
+ /**
+ * Reads given amount of bytes from file.
+ *
+ * @param $bytes Amount of bytes to read
+ * @return $data Data read from file
+ */
+ public function read ($bytes = NULL) {
+ // $bytes shall be integer
+ assert(is_int($bytes));
+
+ // Call pointer instance
+ return $this->getPointerInstance()->read($bytes);
+ }
+
+ /**
+ * Rewinds to the beginning of the file
+ *
+ * @return $status Status of this operation
+ */
+ public function rewind () {
+ // Call pointer instance
+ return $this->getPointerInstance()->rewind();
+ }
+
+ /**
+ * Analyzes entries in index file. This will count all found (and valid)
+ * entries, mark invalid as damaged and count gaps ("fragmentation"). If
+ * only gaps are found, the file is considered as "virgin" (no entries).
+ *
+ * @return void
+ */
+ public function analyzeFile () {
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+
+ // Make sure the file is initialized
+ assert($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 = $this->getCurrentBlock();
+
+ /*
+ * If the block is empty, maybe the whole file is? This could mean
+ * that the file has been pre-allocated.
+ */
+ if (empty($current)) {
+ // Then skip this part
+ continue;
+ } // END - if
+
+ // Debug message
+ /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] current()=%d', __METHOD__, __LINE__, strlen($current)));
+ } // END - while
+
+ // If the last read block is empty, check gaps
+ if (empty($current)) {
+ // Output message
+ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Found a total of %s gaps.', __METHOD__, __LINE__, count($this->gaps)));
+
+ // Check gaps, if the whole file is empty.
+ if ($this->isFileOnlyGaps()) {
+ // Only gaps, so don't continue here.
+ return;
+ } // END - if
+
+ /*
+ * The above call has calculated a total size of all gaps. If the
+ * percentage of gaps passes a "soft" limit and last
+ * defragmentation is to far in the past, or if a "hard" limit has
+ * reached, run defragmentation.
+ */
+ if ($this->isDefragmentationNeeded()) {
+ // Run "defragmentation"
+ $this->doRunDefragmentation();
+ } // END - if
+ } // END - if
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+ }
+
+ /**
+ * Advances to next "block" of bytes
+ *
+ * @return void
+ */
+ public function next () {
+ // Is there nothing to read?
+ if (!$this->valid()) {
+ // Nothing to read
+ return;
+ } // END - if
+
+ // Debug message
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d] key()=%d', __FUNCTION__, __LINE__, $this->key()));
+
+ // Make sure the block instance is set
+ assert($this->getBlockInstance() instanceof CalculatableBlock);
+
+ // First calculate minimum block length
+ $length = $this->getBlockInstance()->calculateMinimumBlockLength();
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d] length=%s', __FUNCTION__, __LINE__, $length));
+
+ // Short be more than zero!
+ assert($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);
+
+ // Debug message
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d] block()=%d,length=%s', __FUNCTION__, __LINE__, strlen($block), $length));
+
+ // Is it all empty?
+ if (strlen(trim($block)) == 0) {
+ // Mark this block as empty
+ $this->markCurrentBlockAsEmpty(strlen($block));
+
+ // Skip to next block
+ continue;
+ } // END - if
+
+ // At this block then
+ $data .= $block;
+
+ // A debug message
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d] data()=%d', __FUNCTION__, __LINE__, strlen($data)));
+ } // END - while
+
+ // 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 = $this->getHeaderSize();
+
+ // Is the seek position at or beyond the header?
+ if ($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();
+ }
+
+ /**
+ * Searches for next suitable gap the given length of data can fit in
+ * including padding bytes.
+ *
+ * @param $length Length of raw data
+ * @return $seekPosition Found next gap's seek position
+ */
+ public function searchNextGap ($length) {
+ // If the file is only gaps, no need to seek
+ if ($this->isFileOnlyGaps()) {
+ // The first empty block is the first one right after the header
+ return ($this->getHeaderSize() + 1);
+ } // END - if
+
+ // @TODO Unfinished
+ $this->partialStub('length=' . $length);
+ }
+}
+
+// [EOF]
+?>
projects / core.git / blobdiff