File Source for DiscISAM.php

<?php
/**
* PHPExcel
*
* Copyright (c) 2006 - 2010 PHPExcel
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* @category PHPExcel
* @package PHPExcel_CachedObjectStorage
* @copyright Copyright (c) 2006 - 2010 PHPExcel (http://www.codeplex.com/PHPExcel)
* @license http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt LGPL
* @version 1.7.3c, 2010-06-01
*/
/**
* PHPExcel_CachedObjectStorage_DiscISAM
*
* @category PHPExcel
* @package PHPExcel_CachedObjectStorage
* @copyright Copyright (c) 2006 - 2010 PHPExcel (http://www.codeplex.com/PHPExcel)
*/
class PHPExcel_CachedObjectStorage_DiscISAM extends PHPExcel_CachedObjectStorage_CacheBase implements PHPExcel_CachedObjectStorage_ICache {
private $_fileName = null;
private $_fileHandle = null;
private function _storeData() {
$this->_currentObject->detach();
fseek($this->_fileHandle,0,SEEK_END);
$offset = ftell($this->_fileHandle);
fwrite($this->_fileHandle, serialize($this->_currentObject));
$this->_cellCache[$this->_currentObjectID] = array('ptr' => $offset,
'sz' => ftell($this->_fileHandle) - $offset
);
$this->_currentObjectID = $this->_currentObject = null;
} // function _storeData()
/**
* Add or Update a cell in cache identified by coordinate address
*
* @param string $pCoord Coordinate address of the cell to update
* @param PHPExcel_Cell $cell Cell to update
* @return void
* @throws Exception
*/
public function addCacheData($pCoord, PHPExcel_Cell $cell) {
if (($pCoord !== $this->_currentObjectID) && ($this->_currentObjectID !== null)) {
$this->_storeData();
}
$this->_currentObjectID = $pCoord;
$this->_currentObject = $cell;
return $cell;
} // function addCacheData()
/**
* Get cell at a specific coordinate
*
* @param string $pCoord Coordinate of the cell
* @throws Exception
* @return PHPExcel_Cell Cell that was found, or null if not found
*/
public function getCacheData($pCoord) {
if ($pCoord === $this->_currentObjectID) {
return $this->_currentObject;
}
$this->_storeData();
// Check if the entry that has been requested actually exists
if (!isset($this->_cellCache[$pCoord])) {
// Return null if requested entry doesn't exist in cache
return null;
}
// Set current entry to the requested entry
$this->_currentObjectID = $pCoord;
fseek($this->_fileHandle,$this->_cellCache[$pCoord]['ptr']);
$this->_currentObject = unserialize(fread($this->_fileHandle,$this->_cellCache[$pCoord]['sz']));
// Re-attach the parent worksheet
$this->_currentObject->attach($this->_parent);
// Return requested entry
return $this->_currentObject;
} // function getCacheData()
public function unsetWorksheetCells() {
if(!is_null($this->_currentObject)) {
$this->_currentObject->detach();
$this->_currentObject = $this->_currentObjectID = null;
}
$this->_cellCache = array();
// detach ourself from the worksheet, so that it can then delete this object successfully
$this->_parent = null;
// Close down the temporary cache file
$this->__destruct();
} // function unsetWorksheetCells()
public function __construct(PHPExcel_Worksheet $parent) {
parent::__construct($parent);
if (is_null($this->_fileHandle)) {
if (function_exists('posix_getpid')) {
$baseUnique = posix_getpid();
} else {
$baseUnique = mt_rand();
}
$this->_fileName = sys_get_temp_dir().'/PHPExcel.'.uniqid($baseUnique,true).'.cache';
$this->_fileHandle = fopen($this->_fileName,'a+');
}
} // function __construct()
public function __destruct() {
if (!is_null($this->_fileHandle)) {
fclose($this->_fileHandle);
unlink($this->_fileName);
}
$this->_fileHandle = null;
} // function __destruct()
}

Source for file DiscISAM.php