gnu-social/extlib/MDB2/LOB.php
2021-07-16 19:44:41 +01:00

265 lines
8.1 KiB
PHP

<?php
// +----------------------------------------------------------------------+
// | PHP version 5 |
// +----------------------------------------------------------------------+
// | Copyright (c) 1998-2006 Manuel Lemos, Tomas V.V.Cox, |
// | Stig. S. Bakken, Lukas Smith |
// | All rights reserved. |
// +----------------------------------------------------------------------+
// | MDB2 is a merge of PEAR DB and Metabases that provides a unified DB |
// | API as well as database abstraction for PHP applications. |
// | This LICENSE is in the BSD license style. |
// | |
// | Redistribution and use in source and binary forms, with or without |
// | modification, are permitted provided that the following conditions |
// | are met: |
// | |
// | Redistributions of source code must retain the above copyright |
// | notice, this list of conditions and the following disclaimer. |
// | |
// | Redistributions in binary form must reproduce the above copyright |
// | notice, this list of conditions and the following disclaimer in the |
// | documentation and/or other materials provided with the distribution. |
// | |
// | Neither the name of Manuel Lemos, Tomas V.V.Cox, Stig. S. Bakken, |
// | Lukas Smith nor the names of his contributors may be used to endorse |
// | or promote products derived from this software without specific prior|
// | written permission. |
// | |
// | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
// | "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
// | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
// | FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
// | REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
// | INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
// | BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS|
// | OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
// | AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
// | LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY|
// | WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
// | POSSIBILITY OF SUCH DAMAGE. |
// +----------------------------------------------------------------------+
// | Author: Lukas Smith <smith@pooteeweet.org> |
// +----------------------------------------------------------------------+
//
// $Id$
/**
* @package MDB2
* @category Database
* @author Lukas Smith <smith@pooteeweet.org>
*/
require_once 'MDB2.php';
/**
* MDB2_LOB: user land stream wrapper implementation for LOB support
*
* @package MDB2
* @category Database
* @author Lukas Smith <smith@pooteeweet.org>
*/
class MDB2_LOB
{
/**
* contains the key to the global MDB2 instance array of the associated
* MDB2 instance
*
* @var integer
* @access protected
*/
var $db_index;
/**
* contains the key to the global MDB2_LOB instance array of the associated
* MDB2_LOB instance
*
* @var integer
* @access protected
*/
var $lob_index;
// {{{ stream_open()
/**
* open stream
*
* @param string specifies the URL that was passed to fopen()
* @param string the mode used to open the file
* @param int holds additional flags set by the streams API
* @param string not used
*
* @return bool
* @access public
*/
function stream_open($path, $mode, $options, &$opened_path)
{
if (!preg_match('/^rb?\+?$/', $mode)) {
return false;
}
$url = parse_url($path);
if (empty($url['host'])) {
return false;
}
$this->db_index = (int)$url['host'];
if (!isset($GLOBALS['_MDB2_databases'][$this->db_index])) {
return false;
}
$db =& $GLOBALS['_MDB2_databases'][$this->db_index];
$this->lob_index = (int)$url['user'];
if (!isset($db->datatype->lobs[$this->lob_index])) {
return false;
}
return true;
}
// }}}
// {{{ stream_read()
/**
* read stream
*
* @param int number of bytes to read
*
* @return string
* @access public
*/
function stream_read($count)
{
if (isset($GLOBALS['_MDB2_databases'][$this->db_index])) {
$db =& $GLOBALS['_MDB2_databases'][$this->db_index];
$db->datatype->_retrieveLOB($db->datatype->lobs[$this->lob_index]);
$data = $db->datatype->_readLOB($db->datatype->lobs[$this->lob_index], $count);
$length = strlen($data);
if ($length == 0) {
$db->datatype->lobs[$this->lob_index]['endOfLOB'] = true;
}
$db->datatype->lobs[$this->lob_index]['position'] += $length;
return $data;
}
}
// }}}
// {{{ stream_write()
/**
* write stream, note implemented
*
* @param string data
*
* @return int
* @access public
*/
function stream_write($data)
{
return 0;
}
// }}}
// {{{ stream_tell()
/**
* return the current position
*
* @return int current position
* @access public
*/
function stream_tell()
{
if (isset($GLOBALS['_MDB2_databases'][$this->db_index])) {
$db =& $GLOBALS['_MDB2_databases'][$this->db_index];
return $db->datatype->lobs[$this->lob_index]['position'];
}
}
// }}}
// {{{ stream_eof()
/**
* Check if stream reaches EOF
*
* @return bool
* @access public
*/
function stream_eof()
{
if (!isset($GLOBALS['_MDB2_databases'][$this->db_index])) {
return true;
}
$db =& $GLOBALS['_MDB2_databases'][$this->db_index];
$result = $db->datatype->_endOfLOB($db->datatype->lobs[$this->lob_index]);
if (version_compare(phpversion(), "5.0", ">=")
&& version_compare(phpversion(), "5.1", "<")
) {
return !$result;
}
return $result;
}
// }}}
// {{{ stream_seek()
/**
* Seek stream, not implemented
*
* @param int offset
* @param int whence
*
* @return bool
* @access public
*/
function stream_seek($offset, $whence)
{
return false;
}
// }}}
// {{{ stream_stat()
/**
* return information about stream
*
* @access public
*/
function stream_stat()
{
if (isset($GLOBALS['_MDB2_databases'][$this->db_index])) {
$db =& $GLOBALS['_MDB2_databases'][$this->db_index];
return array(
'db_index' => $this->db_index,
'lob_index' => $this->lob_index,
);
}
}
// }}}
// {{{ stream_close()
/**
* close stream
*
* @access public
*/
function stream_close()
{
if (isset($GLOBALS['_MDB2_databases'][$this->db_index])) {
$db =& $GLOBALS['_MDB2_databases'][$this->db_index];
if (isset($db->datatype->lobs[$this->lob_index])) {
$db->datatype->_destroyLOB($db->datatype->lobs[$this->lob_index]);
unset($db->datatype->lobs[$this->lob_index]);
}
}
}
// }}}
}
// register streams wrapper
if (!stream_wrapper_register("MDB2LOB", "MDB2_LOB")) {
MDB2::raiseError();
return false;
}
?>