Custom session class

```
db = $pdo;
$this->table_name = (is_null($table_name)) ? $this->table_name : $table_name;
$this->session_name = (is_null($session_name)) ? $this->session_name : $session_name;
$this->session_litetime = (is_null($session_lifetime)) ? $this->session_litetime : $session_lifetime;
session_set_save_handler(
[$this, 'open'], [$this, 'close'], [$this, 'read'], [$this, 'write'], [$this, 'destroy'], [$this, 'gc']
);
register_shutdown_function('session_write_close');
ini_set('session_auto_start', 0);
ini_set('session.cookie_httponly',1);
ini_set('session.use_only_cookies',1);
ini_set('session.gc_probability', 25);
ini_set('session.gc_divisor', 100);
ini_set('session.gc_maxlifetime', $this->session_litetime);
session_name($this->session_name);
session_start();
$this->regenerate_id();
}

private function __clone(){}

public function open($save_path, $session_name){
return true;
}

public function close(){
$this->gc($this->session_litetime);
return true;
}

public function read($session_id){
$session = $this->fetch_session($session_id);
return ($session === false) ? false : $session['data'];
}

public function write($session_id, $session_data){
$session = $this->fetch_session($session_id);
if($session === false)
$stmp = $this->db->prepare('INSERT INTO '.$this->get_table().' (id, data, unixtime) VALUES (:id, :data, :time)');
else
$stmp = $this->db->prepare('UPDATE '.$this->get_table().' SET data = :data, unixtime = :time WHERE id = :id');
$stmp->execute([':id' => $session_id, ':data' => $session_data, ':time' => time()]);
}

public function destroy($session_id){
$stmp = $this->db->prepare('DELETE FROM '.$this->get_table().' WHERE id = :id');
$stmp->exe

For one thing, to increase readability and cleanliness, try organizing your code a little better. You can read more on that here.

In init(), you can use if(is_null(self::$instance)) instead of if(self::$instance == null).

In __construct(), I don't believe your ternaries need parentheses around the is_null functions.

Hopefully you'll be adding to open() because right now it has no purpose. And then in your setter and getter, I suppose you could switch the if statement around so instead of if (!self::check_dot($key)) you'll have if (self::check_dot($key)).

Other than though, your connection looks good and you seem to be handling everything okay!

StackExchange Code Review Q#39010, answer score: 3