* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
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
*
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)
+ );
+
+ // Init counters and gaps array
+ $this->initCountersGapsArray();
+ }
+
+ /**
+ * Reads the file header
+ *
+ * @return void
+ */
+ protected 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->getHeaderSize());
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->getHeaderSize()));
+
+ // Have all requested bytes been read?
+ assert(strlen($data) == $this->getHeaderSize());
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
+
+ // Last character must be the separator
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($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
+ */
+ $header = explode(chr(self::SEPARATOR_HEADER_DATA), $data);
+
+ // Set it here
+ $this->setHeader($header);
+
+ // Check if the array has only 3 elements
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($header), print_r($header, TRUE)));
+ assert(count($header) == 2);
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
+
+ // Check magic
+ assert($header[0] == self::INDEX_MAGIC);
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
+
+ // Check length of count
+ assert(strlen($header[1]) == self::LENGTH_COUNT);
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
+
+ // Decode count
+ $header[1] = hex2bin($header[1]);
+
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+ }
+
+ /**
+ * 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) {
+ // 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();
}
}
projects / core.git / blobdiff