framework/main/classes/index/class_BaseIndex.php

   1 <?php
   2 // Own namespace
   3 namespace CoreFramework\Index;
   4
   5 // Import framework stuff
   6 use CoreFramework\Factory\ObjectFactory;
   7 use CoreFramework\Filesystem\File\BaseBinaryFile;
   8 use CoreFramework\Iterator\Filesystem\SeekableWritableFileIterator;
   9 use CoreFramework\Object\BaseFrameworkSystem;
  10
  11 /**
  12  * A general index class
  13  *
  14  * @author              Roland Haeder <webmaster@ship-simu.org>
  15  * @version             0.0.0
  16  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  17  * @license             GNU GPL 3.0 or any newer version
  18  * @link                http://www.ship-simu.org
  19  *
  20  * This program is free software: you can redistribute it and/or modify
  21  * it under the terms of the GNU General Public License as published by
  22  * the Free Software Foundation, either version 3 of the License, or
  23  * (at your option) any later version.
  24  *
  25  * This program is distributed in the hope that it will be useful,
  26  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  27  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28  * GNU General Public License for more details.
  29  *
  30  * You should have received a copy of the GNU General Public License
  31  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  32  */
  33 class BaseIndex extends BaseFrameworkSystem {
  34         /**
  35          * Magic for this index
  36          */
  37         const INDEX_MAGIC = 'INDEXv0.1';
  38
  39         /**
  40          * Separator group->hash
  41          */
  42         const SEPARATOR_GROUP_HASH = 0x01;
  43
  44         /**
  45          * Separator hash->gap position
  46          */
  47         const SEPARATOR_HASH_GAP_POSITION = 0x02;
  48
  49         /**
  50          * Separator gap position->length
  51          */
  52         const SEPARATOR_GAP_LENGTH = 0x03;
  53
  54         /**
  55          * Protected constructor
  56          *
  57          * @param       $className      Name of the class
  58          * @return      void
  59          */
  60         protected function __construct ($className) {
  61                 // Call parent constructor
  62                 parent::__construct($className);
  63         }
  64
  65         /**
  66          * Reads the file header
  67          *
  68          * @return      void
  69          */
  70         public function readFileHeader () {
  71                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
  72
  73                 // First rewind to beginning as the header sits at the beginning ...
  74                 $this->getIteratorInstance()->rewind();
  75
  76                 // Then read it (see constructor for calculation)
  77                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
  78                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->getIteratorInstance()->getHeaderSize()));
  79
  80                 // Have all requested bytes been read?
  81                 assert(strlen($data) == $this->getIteratorInstance()->getHeaderSize());
  82                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  83
  84                 // Last character must be the separator
  85                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
  86                 assert(substr($data, -1, 1) == chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES));
  87                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  88
  89                 // Okay, then remove it
  90                 $data = substr($data, 0, -1);
  91
  92                 // And update seek position
  93                 $this->getIteratorInstance()->updateSeekPosition();
  94
  95                 /*
  96                  * Now split it:
  97                  *
  98                  * 0 => magic
  99                  * 1 => total entries
 100                  */
 101                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
 102
 103                 // Set it here
 104                 $this->getIteratorInstance()->setHeader($header);
 105
 106                 // Check if the array has only 3 elements
 107                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($header), print_r($header, true)));
 108                 assert(count($header) == 2);
 109                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 110
 111                 // Check magic
 112                 assert($header[0] == self::INDEX_MAGIC);
 113                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 114
 115                 // Check length of count
 116                 assert(strlen($header[1]) == BaseBinaryFile::LENGTH_COUNT);
 117                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 118
 119                 // Decode count
 120                 $header[1] = hex2bin($header[1]);
 121
 122                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 123         }
 124
 125         /**
 126          * Flushes the file header
 127          *
 128          * @return      void
 129          */
 130         public function flushFileHeader () {
 131                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 132
 133                 // Put all informations together
 134                 $header = sprintf('%s%s%s%s',
 135                         // Magic
 136                         self::INDEX_MAGIC,
 137
 138                         // Separator header data
 139                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 140
 141                         // Total entries
 142                         str_pad($this->dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 143
 144                         // Separator header<->entries
 145                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 146                 );
 147
 148                 // Write it to disk (header is always at seek position 0)
 149                 $this->getIteratorInstance()->writeData(0, $header, false);
 150
 151                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 152         }
 153
 154         /**
 155          * Initializes this index
 156          *
 157          * @param       $fileName       File name of this index
 158          * @return      void
 159          * @todo        Currently the index file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole index file.
 160          */
 161         protected function initIndex ($fileName) {
 162                 // Append index file extension
 163                 $fileName .= $this->getConfigInstance()->getConfigEntry('index_extension');
 164
 165                 // Get a file i/o pointer instance for index file
 166                 $fileInstance = ObjectFactory::createObjectByConfiguredName('index_file_class', array($fileName, $this));
 167
 168                 // Get iterator instance
 169                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 170
 171                 // Is the instance implementing the right interface?
 172                 assert($iteratorInstance instanceof SeekableWritableFileIterator);
 173
 174                 // Set iterator here
 175                 $this->setIteratorInstance($iteratorInstance);
 176
 177                 // Calculate header size
 178                 $this->getIteratorInstance()->setHeaderSize(
 179                         strlen(self::INDEX_MAGIC) +
 180                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 181                         BaseBinaryFile::LENGTH_COUNT +
 182                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 183                 );
 184
 185                 // Init counters and gaps array
 186                 $this->getIteratorInstance()->initCountersGapsArray();
 187
 188                 // Is the file's header initialized?
 189                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 190                         // No, then create it (which may pre-allocate the index)
 191                         $this->getIteratorInstance()->createFileHeader();
 192
 193                         // And pre-allocate a bit
 194                         $this->getIteratorInstance()->preAllocateFile('index');
 195                 } // END - if
 196
 197                 // Load the file header
 198                 $this->readFileHeader();
 199
 200                 // Count all entries in file
 201                 $this->getIteratorInstance()->analyzeFile();
 202         }
 203
 204         /**
 205          * Calculates minimum length for one entry/block
 206          *
 207          * @return      $length         Minimum length for one entry/block
 208          */
 209         public function calculateMinimumBlockLength () {
 210                 // Calulcate it
 211                 $length = BaseBinaryFile::LENGTH_TYPE + strlen(chr(BaseBinaryFile::SEPARATOR_TYPE_POSITION)) + BaseBinaryFile::LENGTH_POSITION + strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 212
 213                 // Return it
 214                 return $length;
 215         }
 216
 217         /**
 218          * Determines whether the EOF has been reached
 219          *
 220          * @return      $isEndOfFileReached             Whether the EOF has been reached
 221          * @throws      UnsupportedOperationException   If this method is called
 222          */
 223         public function isEndOfFileReached () {
 224                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 225         }
 226
 227         /**
 228          * Getter for file name
 229          *
 230          * @return      $fileName       The current file name
 231          * @throws      UnsupportedOperationException   If this method is called
 232          */
 233         public function getFileName () {
 234                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 235         }
 236
 237         /**
 238          * Initializes counter for valid entries, arrays for damaged entries and
 239          * an array for gap seek positions. If you call this method on your own,
 240          * please re-analyze the file structure. So you are better to call
 241          * analyzeFile() instead of this method.
 242          *
 243          * @return      void
 244          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 245          */
 246         public function initCountersGapsArray () {
 247                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 248         }
 249
 250         /**
 251          * Getter for header size
 252          *
 253          * @return      $totalEntries   Size of file header
 254          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 255          */
 256         public final function getHeaderSize () {
 257                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 258         }
 259
 260         /**
 261          * Setter for header size
 262          *
 263          * @param       $headerSize             Size of file header
 264          * @return      void
 265          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 266          */
 267         public final function setHeaderSize ($headerSize) {
 268                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 269         }
 270
 271         /**
 272          * Getter for header array
 273          *
 274          * @return      $totalEntries   Size of file header
 275          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 276          */
 277         public final function getHeader () {
 278                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 279         }
 280
 281         /**
 282          * Setter for header
 283          *
 284          * @param       $header         Array for a file header
 285          * @return      void
 286          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 287          */
 288         public final function setHeader (array $header) {
 289                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 290         }
 291
 292         /**
 293          * Updates seekPosition attribute from file to avoid to much access on file.
 294          *
 295          * @return      void
 296          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 297          */
 298         public function updateSeekPosition () {
 299                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 300         }
 301
 302         /**
 303          * Getter for total entries
 304          *
 305          * @return      $totalEntries   Total entries in this file
 306          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 307          */
 308         public final function getCounter () {
 309                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 310         }
 311
 312         /**
 313          * "Getter" for file size
 314          *
 315          * @return      $fileSize       Size of currently loaded file
 316          */
 317         public function getFileSize () {
 318                 // Call iterator's method
 319                 return $this->getIteratorInstance()->getFileSize();
 320         }
 321
 322         /**
 323          * Writes data at given position
 324          *
 325          * @param       $seekPosition   Seek position
 326          * @param       $data                   Data to be written
 327          * @param       $flushHeader    Whether to flush the header (default: flush)
 328          * @return      void
 329          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 330          */
 331         public function writeData ($seekPosition, $data, $flushHeader = true) {
 332                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data[]=%s,flushHeader=%d', __METHOD__, __LINE__, $seekPosition, gettype($data), intval($flushHeader)));
 333                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 334         }
 335
 336         /**
 337          * Writes given value to the file and returns a hash and gap position for it
 338          *
 339          * @param       $groupId        Group identifier
 340          * @param       $value          Value to be added to the stack
 341          * @return      $data           Hash and gap position
 342          * @throws      UnsupportedOperationException   If this method is called
 343          */
 344         public function writeValueToFile ($groupId, $value) {
 345                 self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] groupId=' . $groupId . ',value[' . gettype($value) . ']=' . print_r($value, true));
 346                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 347         }
 348
 349         /**
 350          * Writes given raw data to the file and returns a gap position and length
 351          *
 352          * @param       $groupId        Group identifier
 353          * @param       $hash           Hash from encoded value
 354          * @param       $encoded        Encoded value to be written to the file
 355          * @return      $data           Gap position and length of the raw data
 356          */
 357         public function writeDataToFreeGap ($groupId, $hash, $encoded) {
 358                 self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] groupId=' . $groupId . ',hash=' . $hash . ',encoded()=' . strlen($encoded));
 359                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 360         }
 361
 362 }