package web

import (
	"log"
	"net"
	"time"
)

// tcpKeepAliveListener sets TCP keep-alive timeouts on accepted
// connections. It's used by ListenAndServe and ListenAndServeTLS so
// dead TCP connections (e.g. closing laptop mid-download) eventually
// go away.
type tcpKeepAliveListener struct {
	*net.TCPListener
}

func (ln tcpKeepAliveListener) Accept() (net.Conn, error) {
	tc, err := ln.AcceptTCP()
	if err != nil {
		return nil, err
	}
	err = tc.SetKeepAlive(true)
	if err != nil {
		log.Printf("Error setting Keep-Alive: %v", err)
	}
	err = tc.SetKeepAlivePeriod(3 * time.Minute)
	if err != nil {
		log.Printf("Error setting Keep-Alive period: %v", err)
	}
	return tc, nil
}