<?php
# Copyright (C) 2006-2010 Tobias Leupold <tobias.leupold@web.de>
#
# This file is part of the b8 package
#
# This program 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 in version 2.1 of the License.
#
# This program 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 program; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
/**
* The DBA (Berkeley DB) abstraction layer for communicating with the database.
* Copyright (C) 2006-2010 Tobias Leupold <tobias.leupold@web.de>
*
* @license LGPL
* @access public
* @package b8
* @author Tobias Leupold
*/
class b8_storage_dba extends b8_storage_base
{
public $config = array(
'database' => 'wordlist.db',
'handler' => 'db4',
);
public $b8_config = array(
'degenerator' => NULL,
'today' => NULL
);
private $_db = NULL;
const DATABASE_CONNECTION_FAIL = 'DATABASE_CONNECTION_FAIL';
/**
* Constructs the database layer.
*
* @access public
* @param string $config
*/
function __construct($config, $degenerator, $today)
{
# Pass some variables of the main b8 config to this class
$this->b8_config['degenerator'] = $degenerator;
$this->b8_config['today'] = $today;
# Validate the config items
if(count($config) > 0) {
foreach ($config as $name => $value) {
$this->config[$name] = (string) $value;
}
}
}
/**
* Closes the database connection.
*
* @access public
* @return void
*/
function __destruct()
{
if($this->_db !== NULL) {
dba_close($this->_db);
$this->connected = FALSE;
}
}
/**
* Connect to the database and do some checks.
*
* @access public
* @return mixed Returns TRUE on a successful database connection, otherwise returns a constant from b8.
*/
public function connect()
{
# Have we already connected?
if($this->_db !== NULL)
return TRUE;
# Open the database connection
$this->_db = dba_open(dirname(__FILE__) . DIRECTORY_SEPARATOR . ".." . DIRECTORY_SEPARATOR . $this->config['database'], "w", $this->config['handler']);
if($this->_db === FALSE) {
$this->connected = FALSE;
$this->_db = NULL;
return self::DATABASE_CONNECTION_FAIL;
}
# Everything is okay and connected
$this->connected = TRUE;
# Let's see if this is a b8 database and the version is okay
return $this->check_database();
}
/**
* Does the actual interaction with the database when fetching data.
*
* @access protected
* @param array $tokens
* @return mixed Returns an array of the returned data in the format array(token => data) or an empty array if there was no data.
*/
protected function _get_query($tokens)
{
$data = array();
foreach ($tokens as $token) {
$count = dba_fetch($token, $this->_db);
if($count !== FALSE)
$data[$token] = $count;
}
return $data;
}
/**
* Store a token to the database.
*
* @access protected
* @param string $token
* @param string $count
* @return bool TRUE on success or FALSE on failure
*/
protected function _put($token, $count) {
return dba_insert($token, $count, $this->_db);
}
/**
* Update an existing token.
*
* @access protected
* @param string $token
* @param string $count
* @return bool TRUE on success or FALSE on failure
*/
protected function _update($token, $count)
{
return dba_replace($token, $count, $this->_db);
}
/**
* Remove a token from the database.
*
* @access protected
* @param string $token
* @return bool TRUE on success or FALSE on failure
*/
protected function _del($token)
{
return dba_delete($token, $this->_db);
}
/**
* Does nothing :-D
*
* @access protected
* @return void
*/
protected function _commit()
{
# We just need this function because the (My)SQL backend(s) need it.
return;
}
}
?>
