<?php
/*****************************************************************************
* fileStorage: easy to use class for writing and reading serialized data from
* and to files
*****************************************************************************
* version 1.0 - 2002-09-12 12:15
*****************************************************************************
* Copyright (c) 2002, Emilis Dambauskas, [email protected]
* All rights reserved.
* This class is licensed under The Artistic license, for more info read
* fileStorage.license.txt or go to
* http://www.opensource.org/licenses/artistic-license.php
****************************************************************************/
/*****************************************************************************
* HELP:
* methods:
* - fileStorage($filename) - contructor
* - error($msg) - reports an error
* - read_data() - reads data from file
* - write_data() - writes data to file
* - add_data($name, $value) - adds new value into data storage
* - get_data($name) - gets value from data storage
* - register_data($name, &$value) - adds reference into data storage
* - &get_reg_data($name) - gets reference from data storage
*
* ATTENTION:
* if you want to store data in a file it has to be accessible for writing
* by the web server. So you may need to chmod the file and change its
* access permissions.
****************************************************************************/
/*****************************************************************************
* EXAMPLE (a simple counter stored in the storage):
*
* // we create new storage and associate it with file mydata.dat:
* $storage = &new fileStorage('mydata.dat');
* $storage->read_data();
*
* // try to get counter value from storage
* $counter = $storage->get_data('counter');
*
* // if counter not found:
* if (!$counter)
* $counter = 1;
*
* // increase counter value:
* $counter++;
*
* // store counter value in the storage:
* $storage->add_data('counter', $counter)
* // save storage:
* $storage->write_data();
*
*
****************************************************************************/
class fileStorage
{
var $fp;
var $filename;
var $data;
var $data_read;
/**
* constructor
*
* $filename = name of file to use for storing data
*/
function fileStorage($filename)
{
$this->filename = $filename;
$this->data_read = FALSE;
$this->data = array();
} // end of function fileStore
/**
* reports an error
* tip: you ca attach your own error reporting here
*/
function error($msg)
{
trigger_error('fileStorage error: '.$msg);
} // end of function error
/**
* checks if file exists
* if not tries to create it
*/
function _check_file()
{
if (!file_exists($this->filename))
if(!$this->fp = fopen($this->filename, 'w'))
return FALSE;
else
fclose($this->fp);
return TRUE;
} // end of function _check_file
/**
* reads the file and returns array with data
*/
function read_data()
{
if (!$this->_check_file())
{
$this->error('Couldnot open file '.$this->filename.' for reading.');
return FALSE;
}
$this->fp = fopen ($this->filename, 'r');
$contents = fread ($this->fp, filesize ($this->filename));
fclose ($this->fp);
$this->data = unserialize($contents);
$this->data_read = TRUE;
return $this->data;
} // end of function get_data
/**
* writes data into the file
*/
function write_data()
{
if (!$this->_check_file())
{
$this->error('Couldnot open file '.$this->filename.' for writing.');
return FALSE;
}
$store = serialize($this->data);
$this->fp = fopen($this->filename, 'w');
fwrite($this->fp, $store);
fclose($this->fp);
} // end of function write_data
/**
* adds variable into storage
*/
function add_data($name, $value)
{
if (!$this->data_read)
$this->read_data();
$this->data[(string) $name] = $value;
} // end of function add_data
/**
* returns data stored in storage by that name
*/
function get_data($name)
{
if (!$this->data_read)
$this->read_data();
if (!isset($this->data[(string)$name]))
{
$this->error('Data '.$name.' does not exist in the storage');
return FALSE;
}
return $this->data[(string)$name];
} // end of function get_data
/**
*
*/
function register_data($name, &$value)
{
if (!$this->data_read)
$this->read_data();
$this->data[(string) $name] = &$value;
}
/**
*
*/
function &get_reg_data($name)
{
if (!$this->data_read)
$this->read_data();
if (!isset($this->data[(string)$name]))
{
$this->error('Data '.$name.' does not exist in the storage');
return FALSE;
}
return $this->data[(string)$name];
}
} // end of class fileStorage
?>
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