This call leads nowhere, so better call own method.
[core.git] / inc / classes / main / file_directories / class_BaseFile.php
index bcc61661bba3d15533f1bbb5c51632daebf1dc7f..5fade9baeeaaded5a0f87f0af175e2fed130e20d 100644 (file)
@@ -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();
        }
 
        /**
@@ -52,17 +65,13 @@ class BaseFile extends BaseFrameworkSystem {
        }
 
        /**
-        * Close a file source and set it's instance to null and the file name
-        * to empty
+        * Getter for the file pointer
         *
-        * @return      void
-        * @todo        ~10% done?
+        * @return      $filePointer    The file pointer which shall be a valid file resource
+        * @throws      UnsupportedOperationException   If this method is called
         */
-       public function closeFile () {
-               $this->partialStub('Unfinished method.');
-
-               // Remove file name
-               $this->setFileName('');
+       public final function getPointer () {
+               throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
        }
 
        /**
@@ -85,14 +94,247 @@ 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
+        *
+        * @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       $flushHeader    Whether to flush the header (default: flush)
+        * @return      void
+        */
+       protected function writeData ($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      void
+        * @todo        ~10% done?
+        */
+       public function closeFile () {
+               $this->partialStub('Unfinished method.');
+
+               // Remove file name
+               $this->setFileName('');
+       }
+
        /**
         * Determines seek position
         *
         * @return      $seekPosition   Current seek position
-        * @todo        0% done
         */
-       public final function determineSeekPosition () {
-               $this->partialStub('Unfinished method.');
+       public function determineSeekPosition () {
+               // Call pointer instance
+               return $this->getPointerInstance()->determineSeekPosition();
        }
 
        /**
@@ -101,10 +343,10 @@ class BaseFile extends BaseFrameworkSystem {
         * @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      $status         Status of file seek: 0 = success, -1 = failed
-        * @todo        0% done
         */
        public function seek ($offset, $whence = SEEK_SET) {
-               $this->partialStub('Unfinished method.');
+               // Call pointer instance
+               return $this->getPointerInstance()->seek($offset, $whence);
        }
 
        /**
@@ -112,10 +354,242 @@ class BaseFile extends BaseFrameworkSystem {
         *
         * @return      $size   Size (in bytes) of file
         * @todo        Handle seekStatus
-        * @todo        0% done
         */
        public function size () {
-               $this->partialStub('Unfinished method.');
+               // Call pointer instance
+               return $this->getPointerInstance()->size();
+       }
+
+       /**
+        * Read data a file pointer
+        *
+        * @return      mixed   The result of fread()
+        * @throws      NullPointerException    If the file pointer instance
+        *                                                                      is not set by setPointer()
+        * @throws      InvalidResourceException        If there is being set
+        */
+       public function readFromFile () {
+               // Call pointer instance
+               return $this->getPointerInstance()->readFromFile();
+       }
+
+       /**
+        * Reads given amount of bytes from file.
+        *
+        * @param       $bytes  Amount of bytes to read
+        * @return      $data   Data read from file
+        */
+       public function read ($bytes) {
+               // Call pointer instance
+               return $this->getPointerInstance()->read($bytes);
+       }
+
+       /**
+        * Write data to a file pointer
+        *
+        * @param       $dataStream             The data stream we shall write to the file
+        * @return      mixed                   Number of writes bytes or FALSE on error
+        * @throws      NullPointerException    If the file pointer instance
+        *                                                                      is not set by setPointer()
+        * @throws      InvalidResourceException        If there is being set
+        *                                                                                      an invalid file resource
+        */
+       public function writeToFile ($dataStream) {
+               // Call pointer instance
+               return $this->getPointerInstance()->writeToFile($dataStream);
+       }
+
+       /**
+        * Rewinds to the beginning of the file
+        *
+        * @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();
        }
 }