inc/classes/main/index/file_stack/class_FileStackIndex.php

   1 <?php
   2 /**
   3  * A FileStack index class
   4  *
   5  * @author              Roland Haeder <webmaster@ship-simu.org>
   6  * @version             0.0.0
   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
  10  *
  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.
  15  *
  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.
  20  *
  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/>.
  23  */
  24 class FileStackIndex extends BaseIndex implements IndexableStack, Registerable {
  25         /**
  26          * Protected constructor
  27          *
  28          * @return      void
  29          */
  30         protected function __construct () {
  31                 // Call parent constructor
  32                 parent::__construct(__CLASS__);
  33         }
  34
  35         /**
  36          * Creates an instance of this Index class and prepares it for usage
  37          *
  38          * @param       $fileName               Name of the file stack to create an index file for
  39          * @return      $indexInstance  An instance of this Index class
  40          */
  41         public final static function createFileStackIndex ($fileName) {
  42                 // Get a new instance
  43                 $indexInstance = new FileStackIndex();
  44
  45                 // Initialize index
  46                 $indexInstance->initIndex($fileName);
  47
  48                 // Return the prepared instance
  49                 return $indexInstance;
  50         }
  51
  52         /**
  53          * Adds given hash to an index file
  54          *
  55          * @param       $groupId        Name of stack to add hash for
  56          * @param       $data           Hash and gap position to be added to the index
  57          * @return      void
  58          */
  59         public function addHashToIndex ($groupId, array $data) {
  60                 // Debug message
  61                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,gap=%d,length=%d - CALLED!', __METHOD__, __LINE__, $groupId, $data[BaseFileStack::ARRAY_INDEX_HASH], $data[BaseFileStack::ARRAY_INDEX_GAP_POSITION], $data[BaseFileStack::ARRAY_INDEX_DATA_LENGTH]));
  62
  63                 // Raw data been written to the file
  64                 $rawData = sprintf('%s%s%s%s%s%s%s',
  65                         $groupId,
  66                         self::SEPARATOR_GROUP_HASH,
  67                         hex2bin($data[BaseFileStack::ARRAY_INDEX_HASH]),
  68                         self::SEPARATOR_HASH_GAP_POSITION,
  69                         $data[BaseFileStack::ARRAY_INDEX_GAP_POSITION],
  70                         self::SEPARATOR_GAP_LENGTH,
  71                         $data[BaseFileStack::ARRAY_INDEX_DATA_LENGTH]
  72                 );
  73
  74                 // Debug message
  75                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d', __METHOD__, __LINE__, $groupId, $data[BaseFileStack::ARRAY_INDEX_HASH], strlen($rawData)));
  76
  77                 // Search for next free gap
  78                 $gapPosition = $this->getIteratorInstance()->searchNextGap(strlen($rawData));
  79
  80                 // Gap position cannot be smaller than header length + 1
  81                 assert($gapPosition > $this->getIteratorInstance()->getHeaderSize());
  82
  83                 // Debug message
  84                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,gapPosition=%s', __METHOD__, __LINE__, $groupId, $data[BaseFileStack::ARRAY_INDEX_HASH], $gapPosition));
  85
  86                 // Then write the data at that gap
  87                 $this->getIteratorInstance()->writeData($gapPosition, $rawData);
  88
  89                 // Debug message
  90                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d - EXIT!', __METHOD__, __LINE__, $groupId, $data[BaseFileStack::ARRAY_INDEX_HASH], strlen($rawData)));
  91         }
  92
  93         /**
  94          * Searches for next suitable gap the given length of data can fit in
  95          * including padding bytes.
  96          *
  97          * @param       $length                 Length of raw data
  98          * @return      $seekPosition   Found next gap's seek position
  99          */
 100         public function searchNextGap ($length) {
 101                 $this->partialStub('length=' . $length);
 102         }
 103 }
 104
 105 // [EOF]
 106 ?>