X-Git-Url: https://git.mxchange.org/?p=core.git;a=blobdiff_plain;f=inc%2Fclasses%2Fmain%2Ffile_directories%2Fclass_BaseFile.php;h=5fade9baeeaaded5a0f87f0af175e2fed130e20d;hp=f286fe3a7b1183a91cf54ad7685e1a489e148ac7;hb=d4a9ba3bac64cc833de7b5af32bca2880b6cd542;hpb=382d1f5cddbc8c210cbc399476820415a22ba474 diff --git a/inc/classes/main/file_directories/class_BaseFile.php b/inc/classes/main/file_directories/class_BaseFile.php index f286fe3a..5fade9ba 100644 --- a/inc/classes/main/file_directories/class_BaseFile.php +++ b/inc/classes/main/file_directories/class_BaseFile.php @@ -27,15 +27,28 @@ class BaseFile extends BaseFrameworkSystem { */ 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 parent::__construct($className); + + // Init counters and gaps array + $this->initCountersGapsArray(); } /** @@ -51,6 +64,16 @@ class BaseFile extends BaseFrameworkSystem { parent::__destruct(); } + /** + * Getter for the file pointer + * + * @return $filePointer The file pointer which shall be a valid file resource + * @throws UnsupportedOperationException If this method is called + */ + public final function getPointer () { + throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION); + } + /** * Setter for file name * @@ -71,6 +94,63 @@ class BaseFile extends BaseFrameworkSystem { 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 * @@ -85,6 +165,154 @@ class BaseFile extends BaseFrameworkSystem { $this->setPointerInstance($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 @@ -104,7 +332,8 @@ class BaseFile extends BaseFrameworkSystem { * * @return $seekPosition Current seek position */ - public final function determineSeekPosition () { + public function determineSeekPosition () { + // Call pointer instance return $this->getPointerInstance()->determineSeekPosition(); } @@ -116,6 +345,7 @@ class BaseFile extends BaseFrameworkSystem { * @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); } @@ -126,6 +356,7 @@ class BaseFile extends BaseFrameworkSystem { * @todo Handle seekStatus */ public function size () { + // Call pointer instance return $this->getPointerInstance()->size(); } @@ -138,6 +369,7 @@ class BaseFile extends BaseFrameworkSystem { * @throws InvalidResourceException If there is being set */ public function readFromFile () { + // Call pointer instance return $this->getPointerInstance()->readFromFile(); } @@ -148,6 +380,7 @@ class BaseFile extends BaseFrameworkSystem { * @return $data Data read from file */ public function read ($bytes) { + // Call pointer instance return $this->getPointerInstance()->read($bytes); } @@ -162,6 +395,7 @@ class BaseFile extends BaseFrameworkSystem { * an invalid file resource */ public function writeToFile ($dataStream) { + // Call pointer instance return $this->getPointerInstance()->writeToFile($dataStream); } @@ -171,8 +405,192 @@ class BaseFile extends BaseFrameworkSystem { * @return $status Status of this operation */ public function rewind () { + // Call pointer instance return $this->getPointerInstance()->rewind(); } + + /** + * Determines whether the EOF has been reached + * + * @return $isEndOfFileReached Whether the EOF has been reached + */ + public final function isEndOfFileReached () { + // 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 + * @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]