TimeOut.swift

class TimeOut: NSObject {

    private let queue:dispatch_queue_t
    private let semaphore:dispatch_semaphore_t
    var completion:()->()
    
    convenience init(_ seconds:Double, completion:()->()) {
        self.init(seconds, fireOn:dispatch_get_main_queue(), completion:completion)
    }
    
    required init(_ seconds:Double, fireOn:dispatch_queue_t, completion:()->()) {
        self.semaphore = dispatch_semaphore_create(0)
        self.queue = dispatch_queue_create("timeout", nil)
        self.completion = completion
        super.init()

        dispatch_async(queue) {
            let timeoutTime = dispatch_time(DISPATCH_TIME_NOW, Int64(seconds * Double(NSEC_PER_SEC)));
            
            let result = dispatch_semaphore_wait(self.semaphore, timeoutTime)
            dispatch_async(fireOn) {
                if result != 0 {
                    self.completion()
                }
            }
        }

    }
    
    func satisfy() {
        dispatch_semaphore_signal(semaphore)
    }
    
}

// Usage
var timeout: TimeOut?

func startTimeout() {
    timeout = TimeOut(5.0) {
        [weak self] in
        self?.gotoNext()
    }
}
    
@IBAction func tapAnywhere(sender: AnyObject) {
    timeout?.satisfy()
    gotoNext()
}