3 * A general index class
5 * @author Roland Haeder <webmaster@ship-simu.org>
7 * @copyright Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 Core Developer Team
8 * @license GNU GPL 3.0 or any newer version
9 * @link http://www.ship-simu.org
11 * This program is free software: you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation, either version 3 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 class BaseIndex extends BaseFrameworkSystem {
26 * Magic for this index
28 const INDEX_MAGIC = 'INDEXv0.1';
31 * Separator group->hash
33 const SEPARATOR_GROUP_HASH = 0x01;
36 * Separator hash->gap position
38 const SEPARATOR_HASH_GAP_POSITION = 0x02;
41 * Separator gap position->length
43 const SEPARATOR_GAP_LENGTH = 0x03;
46 * Protected constructor
48 * @param $className Name of the class
51 protected function __construct ($className) {
52 // Call parent constructor
53 parent::__construct($className);
57 * Reads the file header
61 public function readFileHeader () {
62 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
64 // First rewind to beginning as the header sits at the beginning ...
65 $this->getIteratorInstance()->rewind();
67 // Then read it (see constructor for calculation)
68 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
69 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->getIteratorInstance()->getHeaderSize()));
71 // Have all requested bytes been read?
72 assert(strlen($data) == $this->getIteratorInstance()->getHeaderSize());
73 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
75 // Last character must be the separator
76 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
77 assert(substr($data, -1, 1) == chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES));
78 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
80 // Okay, then remove it
81 $data = substr($data, 0, -1);
83 // And update seek position
84 $this->getIteratorInstance()->updateSeekPosition();
92 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
95 $this->getIteratorInstance()->setHeader($header);
97 // Check if the array has only 3 elements
98 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($header), print_r($header, TRUE)));
99 assert(count($header) == 2);
100 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
103 assert($header[0] == self::INDEX_MAGIC);
104 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
106 // Check length of count
107 assert(strlen($header[1]) == BaseBinaryFile::LENGTH_COUNT);
108 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
111 $header[1] = hex2bin($header[1]);
113 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
117 * Flushes the file header
121 public function flushFileHeader () {
122 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
124 // Put all informations together
125 $header = sprintf('%s%s%s%s',
129 // Separator header data
130 chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
133 str_pad($this->dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
135 // Separator header<->entries
136 chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
139 // Write it to disk (header is always at seek position 0)
140 $this->getIteratorInstance()->writeData(0, $header, FALSE);
142 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
146 * Initializes this index
148 * @param $fileName File name of this index
150 * @todo Currently the index file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole index file.
152 protected function initIndex ($fileName) {
153 // Append index file extension
154 $fileName .= $this->getConfigInstance()->getConfigEntry('index_extension');
156 // Get a file i/o pointer instance for index file
157 $fileInstance = ObjectFactory::createObjectByConfiguredName('index_file_class', array($fileName, $this));
159 // Get iterator instance
160 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
162 // Is the instance implementing the right interface?
163 assert($iteratorInstance instanceof SeekableWritableFileIterator);
166 $this->setIteratorInstance($iteratorInstance);
168 // Calculate header size
169 $this->getIteratorInstance()->setHeaderSize(
170 strlen(self::INDEX_MAGIC) +
171 strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
172 BaseBinaryFile::LENGTH_COUNT +
173 strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
176 // Init counters and gaps array
177 $this->getIteratorInstance()->initCountersGapsArray();
179 // Is the file's header initialized?
180 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
181 // No, then create it (which may pre-allocate the index)
182 $this->getIteratorInstance()->createFileHeader();
184 // And pre-allocate a bit
185 $this->getIteratorInstance()->preAllocateFile('index');
188 // Load the file header
189 $this->readFileHeader();
191 // Count all entries in file
192 $this->getIteratorInstance()->analyzeFile();
196 * Calculates minimum length for one entry/block
198 * @return $length Minimum length for one entry/block
200 public function calculateMinimumBlockLength () {
202 $length = BaseBinaryFile::LENGTH_TYPE + strlen(chr(BaseBinaryFile::SEPARATOR_TYPE_POSITION)) + BaseBinaryFile::LENGTH_POSITION + strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
209 * Determines whether the EOF has been reached
211 * @return $isEndOfFileReached Whether the EOF has been reached
212 * @throws UnsupportedOperationException If this method is called
214 public function isEndOfFileReached () {
215 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
219 * Getter for file name
221 * @return $fileName The current file name
222 * @throws UnsupportedOperationException If this method is called
224 public function getFileName () {
225 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
229 * Initializes counter for valid entries, arrays for damaged entries and
230 * an array for gap seek positions. If you call this method on your own,
231 * please re-analyze the file structure. So you are better to call
232 * analyzeFile() instead of this method.
235 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
237 public function initCountersGapsArray () {
238 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
242 * Getter for header size
244 * @return $totalEntries Size of file header
245 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
247 public final function getHeaderSize () {
248 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
252 * Setter for header size
254 * @param $headerSize Size of file header
256 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
258 public final function setHeaderSize ($headerSize) {
259 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
263 * Getter for header array
265 * @return $totalEntries Size of file header
266 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
268 public final function getHeader () {
269 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
275 * @param $header Array for a file header
277 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
279 public final function setHeader (array $header) {
280 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
284 * Updates seekPosition attribute from file to avoid to much access on file.
287 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
289 public function updateSeekPosition () {
290 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
294 * Getter for total entries
296 * @return $totalEntries Total entries in this file
297 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
299 public final function getCounter () {
300 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
304 * "Getter" for file size
306 * @return $fileSize Size of currently loaded file
308 public function getFileSize () {
309 // Call iterator's method
310 return $this->getIteratorInstance()->getFileSize();
314 * Writes data at given position
316 * @param $seekPosition Seek position
317 * @param $data Data to be written
318 * @param $flushHeader Whether to flush the header (default: flush)
320 * @throws UnsupportedOperationException This method is not (and maybe never will be) supported
322 public function writeData ($seekPosition, $data, $flushHeader = TRUE) {
323 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data[]=%s,flushHeader=%d', __METHOD__, __LINE__, $seekPosition, gettype($data), intval($flushHeader)));
324 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
328 * Writes given value to the file and returns a hash and gap position for it
330 * @param $groupId Group identifier
331 * @param $value Value to be added to the stack
332 * @return $data Hash and gap position
333 * @throws UnsupportedOperationException If this method is called
335 public function writeValueToFile ($groupId, $value) {
336 self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] groupId=' . $groupId . ',value[' . gettype($value) . ']=' . print_r($value, TRUE));
337 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
341 * Writes given raw data to the file and returns a gap position and length
343 * @param $groupId Group identifier
344 * @param $hash Hash from encoded value
345 * @param $encoded Encoded value to be written to the file
346 * @return $data Gap position and length of the raw data
348 public function writeDataToFreeGap ($groupId, $hash, $encoded) {
349 self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] groupId=' . $groupId . ',hash=' . $hash . ',encoded()=' . strlen($encoded));
350 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);