X-Git-Url: https://git.mxchange.org/?p=core.git;a=blobdiff_plain;f=inc%2Fclasses%2Fmain%2Findex%2Fclass_BaseIndex.php;h=046ec73613b8910e413be723767eff1d7ae4a2d8;hp=9d019528a4f188d15822e7bcb98899573c4e44f1;hb=510fd302ecdfcb218f0c093a8dfc628682a8d20b;hpb=56f54f7f6f84c157db9a8c5b35193304e752f235 diff --git a/inc/classes/main/index/class_BaseIndex.php b/inc/classes/main/index/class_BaseIndex.php index 9d019528..046ec736 100644 --- a/inc/classes/main/index/class_BaseIndex.php +++ b/inc/classes/main/index/class_BaseIndex.php @@ -22,6 +22,21 @@ * along with this program. If not, see . */ class BaseIndex extends BaseFrameworkSystem { + /** + * Magic for this index + */ + const INDEX_MAGIC = 'INDEXv0.1'; + + /** + * Separator for header data + */ + const SEPARATOR_HEADER_DATA = 0x01; + + /** + * Separator header->entries + */ + const SEPARATOR_HEADER_ENTRIES = 0x02; + /** * Protected constructor * @@ -31,16 +46,185 @@ class BaseIndex extends BaseFrameworkSystem { protected function __construct ($className) { // Call parent constructor parent::__construct($className); + + // Calculate header size + $this->setHeaderSize( + strlen(self::INDEX_MAGIC) + + strlen(self::SEPARATOR_HEADER_DATA) + + self::LENGTH_COUNT + + strlen(self::SEPARATOR_HEADER_ENTRIES) + ); } /** - * Initializes this file based index + * Reads the file header * - * @param $fileName Name of the file to create an index for + * @return void + */ + private function readFileHeader () { + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__)); + + // First rewind to beginning as the header sits at the beginning ... + $this->getIteratorInstance()->rewind(); + + // Then read it (see constructor for calculation) + $data = $this->getIteratorInstance()->read($this->headerSize); + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->headerSize)); + + // Have all requested bytes been read? + assert(strlen($data) == $this->headerSize); + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__)); + + // Last character must be the separator + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1))))); + assert(substr($data, -1, 1) == chr(self::SEPARATOR_HEADER_ENTRIES)); + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__)); + + // Okay, then remove it + $data = substr($data, 0, -1); + + // And update seek position + $this->updateSeekPosition(); + + /* + * Now split it: + * + * 0 => magic + * 1 => total entries + */ + $this->header = explode(chr(self::SEPARATOR_HEADER_DATA), $data); + + // Check if the array has only 3 elements + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($this->header), print_r($this->header, TRUE))); + assert(count($this->header) == 2); + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__)); + + // Check magic + assert($this->header[0] == self::INDEX_MAGIC); + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__)); + + // Check length of count + assert(strlen($this->header[1]) == self::LENGTH_COUNT); + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__)); + + // Decode count + $this->header[1] = hex2bin($this->header[1]); + + //* 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 + */ + private 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->getIteratorInstance()->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; + } + + /** + * Flushes the file header + * + * @return void + */ + private function flushFileHeader () { + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__)); + + // Put all informations together + $header = sprintf('%s%s', + // Magic + self::INDEX_MAGIC, + + // Separator position<->entries + chr(self::SEPARATOR_HEADER_ENTRIES) + ); + + // Write it to disk (header is always at seek position 0) + $this->writeData(0, $header); + + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__)); + } + + /** + * Analyzes entries in index file. This will count all found (and valid) + * entries, mark invalid as damaged and count gaps ("fragmentation"). If + * only gaps are found, the file is considered as "virgin" (no entries). + * + * @return void + */ + private function analyzeFile () { + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__)); + + // Make sure the file is initialized + assert($this->isFileInitialized()); + + // Init counters and gaps array + $this->initGapsArray(); + + // 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__)); + + //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__)); + } + + /** + * Initializes this index + * + * @param $fileName File name of this index * @return void */ protected function initIndex ($fileName) { - // @TODO + // Get a file i/o pointer instance for index file + $pointerInstance = ObjectFactory::createObjectByConfiguredName('file_raw_input_output_class', array($fileName)); + + // Get iterator instance + $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_io_iterator_class', array($pointerInstance)); + + // Is the instance implementing the right interface? + assert($iteratorInstance instanceof SeekableWritableFileIterator); + + // Set iterator here + $this->setIteratorInstance($iteratorInstance); + + // Is the file's header initialized? + if (!$this->isFileHeaderInitialized()) { + // No, then create it (which may pre-allocate the index) + $this->createFileHeader(); + + // And pre-allocate a bit + $this->preAllocateFile('index'); + } // END - if + + // Load the file header + $this->readFileHeader(); + + // Count all entries in file + $this->analyzeFile(); } }