adodb-session2.php

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<?php


/*
V5.19  23-Apr-2014  (c) 2000-2014 John Lim (jlim#natsoft.com). All rights reserved.
         Contributed by Ross Smith (adodb@netebb.com).
  Released under both BSD license and Lesser GPL library license.
  Whenever there is any discrepancy between the two licenses,
  the BSD license will take precedence.
      Set tabs to 4 for best viewing.


*/

/*

CREATE Table SCripts

Oracle
======

CREATE TABLE SESSIONS2
(
  SESSKEY    VARCHAR2(48 BYTE)                  NOT NULL,
  EXPIRY     DATE                               NOT NULL,
  EXPIREREF  VARCHAR2(200 BYTE),
  CREATED    DATE                               NOT NULL,
  MODIFIED   DATE                               NOT NULL,
  SESSDATA   CLOB,
  PRIMARY KEY(SESSKEY)
);


CREATE INDEX SESS2_EXPIRY ON SESSIONS2(EXPIRY);
CREATE UNIQUE INDEX SESS2_PK ON SESSIONS2(SESSKEY);
CREATE INDEX SESS2_EXP_REF ON SESSIONS2(EXPIREREF);



 MySQL
 =====

CREATE TABLE sessions2(
    sesskey VARCHAR( 64 ) NOT NULL DEFAULT '',
    expiry TIMESTAMP NOT NULL ,
    expireref VARCHAR( 250 ) DEFAULT '',
    created TIMESTAMP NOT NULL ,
    modified TIMESTAMP NOT NULL ,
    sessdata LONGTEXT DEFAULT '',
    PRIMARY KEY ( sesskey ) ,
    INDEX sess2_expiry( expiry ),
    INDEX sess2_expireref( expireref )
)


*/

if (!defined('_ADODB_LAYER')) {
    require realpath(dirname(__FILE__) . '/../adodb.inc.php');
}

if (defined('ADODB_SESSION')) return 1;

define('ADODB_SESSION', dirname(__FILE__));
define('ADODB_SESSION2', ADODB_SESSION);

/*
    Unserialize session data manually. See http://phplens.com/lens/lensforum/msgs.php?id=9821

    From Kerr Schere, to unserialize session data stored via ADOdb.
    1. Pull the session data from the db and loop through it.
    2. Inside the loop, you will need to urldecode the data column.
    3. After urldecode, run the serialized string through this function:

*/
function adodb_unserialize( $serialized_string )
{
    $variables = array( );
    $a = preg_split( "/(\w+)\|/", $serialized_string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE );
    for( $i = 0; $i < count( $a ); $i = $i+2 ) {
        $variables[$a[$i]] = unserialize( $a[$i+1] );
    }
    return( $variables );
}

/*
    Thanks Joe Li. See http://phplens.com/lens/lensforum/msgs.php?id=11487&x=1
    Since adodb 4.61.
*/
function adodb_session_regenerate_id()
{
    $conn = ADODB_Session::_conn();
    if (!$conn) return false;

    $old_id = session_id();
    if (function_exists('session_regenerate_id')) {
        session_regenerate_id();
    } else {
        session_id(md5(uniqid(rand(), true)));
        $ck = session_get_cookie_params();
        setcookie(session_name(), session_id(), false, $ck['path'], $ck['domain'], $ck['secure']);
        //@session_start();
    }
    $new_id = session_id();
    $ok = $conn->Execute('UPDATE '. ADODB_Session::table(). ' SET sesskey='. $conn->qstr($new_id). ' WHERE sesskey='.$conn->qstr($old_id));

    /* it is possible that the update statement fails due to a collision */
    if (!$ok) {
        session_id($old_id);
        if (empty($ck)) $ck = session_get_cookie_params();
        setcookie(session_name(), session_id(), false, $ck['path'], $ck['domain'], $ck['secure']);
        return false;
    }

    return true;
}

/*
    Generate database table for session data
    @see http://phplens.com/lens/lensforum/msgs.php?id=12280
    @return 0 if failure, 1 if errors, 2 if successful.
    @author Markus Staab http://www.public-4u.de
*/
function adodb_session_create_table($schemaFile=null,$conn = null)
{
    // set default values
    if ($schemaFile===null) $schemaFile = ADODB_SESSION . '/session_schema2.xml';
    if ($conn===null) $conn = ADODB_Session::_conn();

    if (!$conn) return 0;

    $schema = new adoSchema($conn);
    $schema->ParseSchema($schemaFile);
    return $schema->ExecuteSchema();
}

class ADODB_Session {
    // getter/setter methods

    /*

    function Lock($lock=null)
    {
    static $_lock = false;

        if (!is_null($lock)) $_lock = $lock;
        return $lock;
    }
    */
    static function driver($driver = null)
    {
        static $_driver = 'mysql';
        static $set = false;

        if (!is_null($driver)) {
            $_driver = trim($driver);
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_DRIVER'])) {
                return $GLOBALS['ADODB_SESSION_DRIVER'];
            }
        }

        return $_driver;
    }

    static function host($host = null) {
        static $_host = 'localhost';
        static $set = false;

        if (!is_null($host)) {
            $_host = trim($host);
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_CONNECT'])) {
                return $GLOBALS['ADODB_SESSION_CONNECT'];
            }
        }

        return $_host;
    }

    static function user($user = null)
    {
        static $_user = 'root';
        static $set = false;

        if (!is_null($user)) {
            $_user = trim($user);
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_USER'])) {
                return $GLOBALS['ADODB_SESSION_USER'];
            }
        }

        return $_user;
    }

    static function password($password = null)
    {
        static $_password = '';
        static $set = false;

        if (!is_null($password)) {
            $_password = $password;
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_PWD'])) {
                return $GLOBALS['ADODB_SESSION_PWD'];
            }
        }

        return $_password;
    }

    static function database($database = null)
    {
        static $_database = '';
        static $set = false;

        if (!is_null($database)) {
            $_database = trim($database);
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_DB'])) {
                return $GLOBALS['ADODB_SESSION_DB'];
            }
        }
        return $_database;
    }

    static function persist($persist = null)
    {
        static $_persist = true;

        if (!is_null($persist)) {
            $_persist = trim($persist);
        }

        return $_persist;
    }

    static function lifetime($lifetime = null)
    {
        static $_lifetime;
        static $set = false;

        if (!is_null($lifetime)) {
            $_lifetime = (int) $lifetime;
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESS_LIFE'])) {
                return $GLOBALS['ADODB_SESS_LIFE'];
            }
        }
        if (!$_lifetime) {
            $_lifetime = ini_get('session.gc_maxlifetime');
            if ($_lifetime <= 1) {
                // bug in PHP 4.0.3 pl 1  -- how about other versions?
                //print "<h3>Session Error: PHP.INI setting <i>session.gc_maxlifetime</i>not set: $lifetime</h3>";
                $_lifetime = 1440;
            }
        }

        return $_lifetime;
    }

    static function debug($debug = null)
    {
        static $_debug = false;
        static $set = false;

        if (!is_null($debug)) {
            $_debug = (bool) $debug;

            $conn = ADODB_Session::_conn();
            if ($conn) {
                #$conn->debug = $_debug;
            }
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESS_DEBUG'])) {
                return $GLOBALS['ADODB_SESS_DEBUG'];
            }
        }

        return $_debug;
    }

    static function expireNotify($expire_notify = null)
    {
        static $_expire_notify;
        static $set = false;

        if (!is_null($expire_notify)) {
            $_expire_notify = $expire_notify;
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_EXPIRE_NOTIFY'])) {
                return $GLOBALS['ADODB_SESSION_EXPIRE_NOTIFY'];
            }
        }

        return $_expire_notify;
    }

    static function table($table = null)
    {
        static $_table = 'sessions2';
        static $set = false;

        if (!is_null($table)) {
            $_table = trim($table);
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_TBL'])) {
                return $GLOBALS['ADODB_SESSION_TBL'];
            }
        }

        return $_table;
    }

    static function optimize($optimize = null)
    {
        static $_optimize = false;
        static $set = false;

        if (!is_null($optimize)) {
            $_optimize = (bool) $optimize;
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (defined('ADODB_SESSION_OPTIMIZE')) {
                return true;
            }
        }

        return $_optimize;
    }

    static function syncSeconds($sync_seconds = null) {
        //echo ("<p>WARNING: ADODB_SESSION::syncSeconds is longer used, please remove this function for your code</p>");

        return 0;
    }

    static function clob($clob = null) {
        static $_clob = false;
        static $set = false;

        if (!is_null($clob)) {
            $_clob = strtolower(trim($clob));
            $set = true;
        } elseif (!$set) {
            // backwards compatibility
            if (isset($GLOBALS['ADODB_SESSION_USE_LOBS'])) {
                return $GLOBALS['ADODB_SESSION_USE_LOBS'];
            }
        }

        return $_clob;
    }

    static function dataFieldName($data_field_name = null) {
        //echo ("<p>WARNING: ADODB_SESSION::dataFieldName() is longer used, please remove this function for your code</p>");
        return '';
    }

    static function filter($filter = null) {
        static $_filter = array();

        if (!is_null($filter)) {
            if (!is_array($filter)) {
                $filter = array($filter);
            }
            $_filter = $filter;
        }

        return $_filter;
    }

    static function encryptionKey($encryption_key = null) {
        static $_encryption_key = 'CRYPTED ADODB SESSIONS ROCK!';

        if (!is_null($encryption_key)) {
            $_encryption_key = $encryption_key;
        }

        return $_encryption_key;
    }

    // private methods

    static function _conn($conn=null) {
        return isset($GLOBALS['ADODB_SESS_CONN']) ? $GLOBALS['ADODB_SESS_CONN'] : false;
    }

    static function _crc($crc = null) {
        static $_crc = false;

        if (!is_null($crc)) {
            $_crc = $crc;
        }

        return $_crc;
    }

    static function _init() {
        session_module_name('user');
        session_set_save_handler(
            array('ADODB_Session', 'open'),
            array('ADODB_Session', 'close'),
            array('ADODB_Session', 'read'),
            array('ADODB_Session', 'write'),
            array('ADODB_Session', 'destroy'),
            array('ADODB_Session', 'gc')
        );
    }


    static function _sessionKey() {
        // use this function to create the encryption key for crypted sessions
        // crypt the used key, ADODB_Session::encryptionKey() as key and session_id() as salt
        return crypt(ADODB_Session::encryptionKey(), session_id());
    }

    static function _dumprs(&$rs) {
        $conn   = ADODB_Session::_conn();
        $debug  = ADODB_Session::debug();

        if (!$conn) {
            return;
        }

        if (!$debug) {
            return;
        }

        if (!$rs) {
            echo "<br />\$rs is null or false<br />\n";
            return;
        }

        //echo "<br />\nAffected_Rows=",$conn->Affected_Rows(),"<br />\n";

        if (!is_object($rs)) {
            return;
        }
        $rs = $conn->_rs2rs($rs);

        require_once ADODB_SESSION.'/../tohtml.inc.php';
        rs2html($rs);
        $rs->MoveFirst();
    }

    // public methods

    static function config($driver, $host, $user, $password, $database=false,$options=false)
    {
        ADODB_Session::driver($driver);
        ADODB_Session::host($host);
        ADODB_Session::user($user);
        ADODB_Session::password($password);
        ADODB_Session::database($database);

        if (strncmp($driver, 'oci8', 4) == 0) $options['lob'] = 'CLOB';

        if (isset($options['table'])) ADODB_Session::table($options['table']);
        if (isset($options['lob'])) ADODB_Session::clob($options['lob']);
        if (isset($options['debug'])) ADODB_Session::debug($options['debug']);
    }

    static function open($save_path, $session_name, $persist = null)
    {
        $conn = ADODB_Session::_conn();

        if ($conn) {
            return true;
        }

        $database   = ADODB_Session::database();
        $debug      = ADODB_Session::debug();
        $driver     = ADODB_Session::driver();
        $host       = ADODB_Session::host();
        $password   = ADODB_Session::password();
        $user       = ADODB_Session::user();

        if (!is_null($persist)) {
            ADODB_Session::persist($persist);
        } else {
            $persist = ADODB_Session::persist();
        }

# these can all be defaulted to in php.ini
#       assert('$database');
#       assert('$driver');
#       assert('$host');

        $conn = ADONewConnection($driver);

        if ($debug) {
            $conn->debug = true;
            ADOConnection::outp( " driver=$driver user=$user db=$database ");
        }

        if (empty($conn->_connectionID)) { // not dsn
            if ($persist) {
                switch($persist) {
                default:
                case 'P': $ok = $conn->PConnect($host, $user, $password, $database); break;
                case 'C': $ok = $conn->Connect($host, $user, $password, $database); break;
                case 'N': $ok = $conn->NConnect($host, $user, $password, $database); break;
                }
            } else {
                $ok = $conn->Connect($host, $user, $password, $database);
            }
        }

        if ($ok) $GLOBALS['ADODB_SESS_CONN'] = $conn;
        else
            ADOConnection::outp('<p>Session: connection failed</p>', false);


        return $ok;
    }

    static function close()
    {
/*
        $conn = ADODB_Session::_conn();
        if ($conn) $conn->Close();
*/
        return true;
    }

    /*
        Slurp in the session variables and return the serialized string
    */
    static function read($key)
    {
        $conn   = ADODB_Session::_conn();
        $filter = ADODB_Session::filter();
        $table  = ADODB_Session::table();

        if (!$conn) {
            return '';
        }

        //assert('$table');

        $binary = $conn->dataProvider === 'mysql' ? '/*! BINARY */' : '';

        global $ADODB_SESSION_SELECT_FIELDS;
        if (!isset($ADODB_SESSION_SELECT_FIELDS)) $ADODB_SESSION_SELECT_FIELDS = 'sessdata';
        $sql = "SELECT $ADODB_SESSION_SELECT_FIELDS FROM $table WHERE sesskey = $binary ".$conn->Param(0)." AND expiry >= " . $conn->sysTimeStamp;

        /* Lock code does not work as it needs to hold transaction within whole page, and we don't know if
          developer has commited elsewhere... :(
         */
        #if (ADODB_Session::Lock())
        #   $rs = $conn->RowLock($table, "$binary sesskey = $qkey AND expiry >= " . time(), sessdata);
        #else
            $rs = $conn->Execute($sql, array($key));
        //ADODB_Session::_dumprs($rs);
        if ($rs) {
            if ($rs->EOF) {
                $v = '';
            } else {
                $v = reset($rs->fields);
                $filter = array_reverse($filter);
                foreach ($filter as $f) {
                    if (is_object($f)) {
                        $v = $f->read($v, ADODB_Session::_sessionKey());
                    }
                }
                $v = rawurldecode($v);
            }

            $rs->Close();

            ADODB_Session::_crc(strlen($v) . crc32($v));
            return $v;
        }

        return '';
    }

    static function write($key, $oval)
    {
    global $ADODB_SESSION_READONLY;

        if (!empty($ADODB_SESSION_READONLY)) return;

        $clob           = ADODB_Session::clob();
        $conn           = ADODB_Session::_conn();
        $crc            = ADODB_Session::_crc();
        $debug          = ADODB_Session::debug();
        $driver         = ADODB_Session::driver();
        $expire_notify  = ADODB_Session::expireNotify();
        $filter         = ADODB_Session::filter();
        $lifetime       = ADODB_Session::lifetime();
        $table          = ADODB_Session::table();

        if (!$conn) {
            return false;
        }
        if ($debug) $conn->debug = 1;
        $sysTimeStamp = $conn->sysTimeStamp;

        //assert('$table');

        $expiry = $conn->OffsetDate($lifetime/(24*3600),$sysTimeStamp);

        $binary = $conn->dataProvider === 'mysql' ? '/*! BINARY */' : '';

        // crc32 optimization since adodb 2.1
        // now we only update expiry date, thx to sebastian thom in adodb 2.32
        if ($crc !== '00' && $crc !== false && $crc == (strlen($oval) . crc32($oval))) {
            if ($debug) {
                echo '<p>Session: Only updating date - crc32 not changed</p>';
            }

            $expirevar = '';
            if ($expire_notify) {
                $var = reset($expire_notify);
                global $$var;
                if (isset($$var)) {
                    $expirevar = $$var;
                }
            }


            $sql = "UPDATE $table SET expiry = $expiry ,expireref=".$conn->Param('0').", modified = $sysTimeStamp WHERE $binary sesskey = ".$conn->Param('1')." AND expiry >= $sysTimeStamp";
            $rs = $conn->Execute($sql,array($expirevar,$key));
            return true;
        }
        $val = rawurlencode($oval);
        foreach ($filter as $f) {
            if (is_object($f)) {
                $val = $f->write($val, ADODB_Session::_sessionKey());
            }
        }

        $expireref = '';
        if ($expire_notify) {
            $var = reset($expire_notify);
            global $$var;
            if (isset($$var)) {
                $expireref = $$var;
            }
        }

        if (!$clob) {   // no lobs, simply use replace()
            $rs = $conn->Execute("SELECT COUNT(*) AS cnt FROM $table WHERE $binary sesskey = ".$conn->Param(0),array($key));
            if ($rs) $rs->Close();

            if ($rs && reset($rs->fields) > 0) {
                $sql = "UPDATE $table SET expiry=$expiry, sessdata=".$conn->Param(0).", expireref= ".$conn->Param(1).",modified=$sysTimeStamp WHERE sesskey = ".$conn->Param(2);

            } else {
                $sql = "INSERT INTO $table (expiry, sessdata, expireref, sesskey, created, modified)
                    VALUES ($expiry,".$conn->Param('0').", ". $conn->Param('1').", ".$conn->Param('2').", $sysTimeStamp, $sysTimeStamp)";
            }


            $rs = $conn->Execute($sql,array($val,$expireref,$key));

        } else {
            // what value shall we insert/update for lob row?
            if (strncmp($driver, 'oci8', 4) == 0) $lob_value = sprintf('empty_%s()', strtolower($clob));
            else $lob_value = 'null';

            $conn->StartTrans();

            $rs = $conn->Execute("SELECT COUNT(*) AS cnt FROM $table WHERE $binary sesskey = ".$conn->Param(0),array($key));

            if ($rs && reset($rs->fields) > 0) {
                $sql = "UPDATE $table SET expiry=$expiry, sessdata=$lob_value, expireref= ".$conn->Param(0).",modified=$sysTimeStamp WHERE sesskey = ".$conn->Param('1');

            } else {
                $sql = "INSERT INTO $table (expiry, sessdata, expireref, sesskey, created, modified)
                    VALUES ($expiry,$lob_value, ". $conn->Param('0').", ".$conn->Param('1').", $sysTimeStamp, $sysTimeStamp)";
            }

            $rs = $conn->Execute($sql,array($expireref,$key));

            $qkey = $conn->qstr($key);
            $rs2 = $conn->UpdateBlob($table, 'sessdata', $val, " sesskey=$qkey", strtoupper($clob));
            if ($debug) echo "<hr>",htmlspecialchars($oval), "<hr>";
            $rs = @$conn->CompleteTrans();


        }

        if (!$rs) {
            ADOConnection::outp('<p>Session Replace: ' . $conn->ErrorMsg() . '</p>', false);
            return false;
        }  else {
            // bug in access driver (could be odbc?) means that info is not committed
            // properly unless select statement executed in Win2000
            if ($conn->databaseType == 'access') {
                $sql = "SELECT sesskey FROM $table WHERE $binary sesskey = $qkey";
                $rs = $conn->Execute($sql);
                ADODB_Session::_dumprs($rs);
                if ($rs) {
                    $rs->Close();
                }
            }
        }/*
        if (ADODB_Session::Lock()) {
            $conn->CommitTrans();
        }*/
        return $rs ? true : false;
    }

    static function destroy($key) {
        $conn           = ADODB_Session::_conn();
        $table          = ADODB_Session::table();
        $expire_notify  = ADODB_Session::expireNotify();

        if (!$conn) {
            return false;
        }
        $debug          = ADODB_Session::debug();
        if ($debug) $conn->debug = 1;
        //assert('$table');

        $qkey = $conn->quote($key);
        $binary = $conn->dataProvider === 'mysql' ? '/*! BINARY */' : '';

        if ($expire_notify) {
            reset($expire_notify);
            $fn = next($expire_notify);
            $savem = $conn->SetFetchMode(ADODB_FETCH_NUM);
            $sql = "SELECT expireref, sesskey FROM $table WHERE $binary sesskey = $qkey";
            $rs = $conn->Execute($sql);
            ADODB_Session::_dumprs($rs);
            $conn->SetFetchMode($savem);
            if (!$rs) {
                return false;
            }
            if (!$rs->EOF) {
                $ref = $rs->fields[0];
                $key = $rs->fields[1];
                //assert('$ref');
                //assert('$key');
                $fn($ref, $key);
            }
            $rs->Close();
        }

        $sql = "DELETE FROM $table WHERE $binary sesskey = $qkey";
        $rs = $conn->Execute($sql);
        if ($rs) {
            $rs->Close();
        }

        return $rs ? true : false;
    }

    static function gc($maxlifetime)
    {
        $conn           = ADODB_Session::_conn();
        $debug          = ADODB_Session::debug();
        $expire_notify  = ADODB_Session::expireNotify();
        $optimize       = ADODB_Session::optimize();
        $table          = ADODB_Session::table();

        if (!$conn) {
            return false;
        }


        $debug          = ADODB_Session::debug();
        if ($debug) {
            $conn->debug = 1;
            $COMMITNUM = 2;
        } else {
            $COMMITNUM = 20;
        }

        //assert('$table');

        $time = $conn->OffsetDate(-$maxlifetime/24/3600,$conn->sysTimeStamp);
        $binary = $conn->dataProvider === 'mysql' ? '/*! BINARY */' : '';

        if ($expire_notify) {
            reset($expire_notify);
            $fn = next($expire_notify);
        } else {
            $fn = false;
        }

        $savem = $conn->SetFetchMode(ADODB_FETCH_NUM);
        $sql = "SELECT expireref, sesskey FROM $table WHERE expiry < $time ORDER BY 2"; # add order by to prevent deadlock
        $rs = $conn->SelectLimit($sql,1000);
        if ($debug) ADODB_Session::_dumprs($rs);
        $conn->SetFetchMode($savem);
        if ($rs) {
            $tr = $conn->hasTransactions;
            if ($tr) $conn->BeginTrans();
            $keys = array();
            $ccnt = 0;
            while (!$rs->EOF) {
                $ref = $rs->fields[0];
                $key = $rs->fields[1];
                if ($fn) $fn($ref, $key);
                $del = $conn->Execute("DELETE FROM $table WHERE sesskey=".$conn->Param('0'),array($key));
                $rs->MoveNext();
                $ccnt += 1;
                if ($tr && $ccnt % $COMMITNUM == 0) {
                    if ($debug) echo "Commit<br>\n";
                    $conn->CommitTrans();
                    $conn->BeginTrans();
                }
            }
            $rs->Close();

            if ($tr) $conn->CommitTrans();
        }


        // suggested by Cameron, "GaM3R" <gamr@outworld.cx>
        if ($optimize) {
            $driver = ADODB_Session::driver();

            if (preg_match('/mysql/i', $driver)) {
                $sql = "OPTIMIZE TABLE $table";
            }
            if (preg_match('/postgres/i', $driver)) {
                $sql = "VACUUM $table";
            }
            if (!empty($sql)) {
                $conn->Execute($sql);
            }
        }


        return true;
    }
}

ADODB_Session::_init();
if (empty($ADODB_SESSION_READONLY))
    register_shutdown_function('session_write_close');

// for backwards compatability only
function adodb_sess_open($save_path, $session_name, $persist = true) {
    return ADODB_Session::open($save_path, $session_name, $persist);
}

// for backwards compatability only
function adodb_sess_gc($t)
{
    return ADODB_Session::gc($t);
}