Method lock

/**
 * Set lock flag on cached item
 *
 * @param   string  $id        The cache data ID
 * @param   string  $group     The cache data group
 * @param   string  $locktime  The default locktime for locking the cache.
 *
 * @return  \stdClass  Object with properties of lock and locklooped
 *
 * @since   1.7.0
 */
public function lock($id, $group = null, $locktime = null)
{
    $returning = new \stdClass();
    $returning->locklooped = false;
    if (!$this->getCaching()) {
        $returning->locked = false;
        return $returning;
    }
    // Get the default group
    $group = $group ?: $this->_options['defaultgroup'];
    // Get the default locktime
    $locktime = $locktime ?: $this->_options['locktime'];
    /*
     * Allow storage handlers to perform locking on their own
     * NOTE drivers with lock need also unlock or unlocking will fail because of false $id
     */
    $handler = $this->_getStorage();
    if ($this->_options['locking'] == true) {
        $locked = $handler->lock($id, $group, $locktime);
        if ($locked !== false) {
            return $locked;
        }
    }
    // Fallback
    $curentlifetime = $this->_options['lifetime'];
    // Set lifetime to locktime for storing in children
    $this->_options['lifetime'] = $locktime;
    $looptime = $locktime * 10;
    $id2 = $id . '_lock';
    if ($this->_options['locking'] == true) {
        $data_lock = $handler->get($id2, $group, $this->_options['checkTime']);
    } else {
        $data_lock = false;
        $returning->locked = false;
    }
    if ($data_lock !== false) {
        $lock_counter = 0;
        // Loop until you find that the lock has been released. That implies that data get from other thread has finished
        while ($data_lock !== false) {
            if ($lock_counter > $looptime) {
                $returning->locked = false;
                $returning->locklooped = true;
                break;
            }
            usleep(100);
            $data_lock = $handler->get($id2, $group, $this->_options['checkTime']);
            $lock_counter++;
        }
    }
    if ($this->_options['locking'] == true) {
        $returning->locked = $handler->store($id2, $group, 1);
    }
    // Revert lifetime to previous one
    $this->_options['lifetime'] = $curentlifetime;
    return $returning;
}