Storage::isAvailable PHP Method

    public function isAvailable()
    {
        if (!is_file($this->file)) {
            if (!touch($this->file)) {
                $this->error = "Storage file could not be created. Please create the storage file manually, it must be writable: {$this->file}";
            }
            return false;
        }
        if (!is_writable($this->file)) {
            @chmod($this->file, 0755);
            if (!is_writable($this->file)) {
                $this->error = "Please make the storage file writable: {$this->file}";
                return false;
            }
        }
        return true;
    }