func handleClient(conn net.Conn, c chan *email.SMTPEmail) {
client := client.MakeClient(conn)
defer client.Close()
// close on shutdown using strategy from http://stackoverflow.com/a/13419724
quit := false
id, shutdownRequested := shutdown.AddShutdownListener("Client processor")
defer shutdown.RoutineDone(id)
go func() {
<-shutdownRequested
quit = true
client.Close()
}()
err := client.BeginReceive(c)
if err != nil {
if quit {
log.Info("Shutting down client")
return
}
log.WithFields(log.Fields{
"error": err.Error(),
}).Info("error encountered, closing client connection")
}
}
// Listens for connections on the given listener and puts them in the channel.
// Blocks while still receiving connections.
// Returns an error on network problem, or nil if shutdown requested
func listenForConnections(l net.Listener, c chan net.Conn) error {
id, shutdownRequested := shutdown.AddShutdownListener("Connection listener")
defer shutdown.RoutineDone(id)
log.WithFields(log.Fields{
"listening_on": fmt.Sprintf("%v", l.Addr()),
"fqdn": config.GetFQDN(),
}).Info("Starting connection listener")
// shutdown using the strategy found here http://stackoverflow.com/a/13419724
quit := false
go func() {
<-shutdownRequested
quit = true
l.Close()
}()
for {
conn, err := l.Accept()
if err != nil {
if quit {
log.Info("Shutting down connection listener")
return nil
}
l.Close()
return err
}
c <- conn
}
}
func handleClients(cxnChan chan net.Conn, emChan chan *email.SMTPEmail) {
id, shutdownRequested := shutdown.AddShutdownListener("Client handler")
defer shutdown.RoutineDone(id)
for {
select {
case cxn := <-cxnChan:
go handleClient(cxn, emChan)
case <-shutdownRequested:
log.Info("Shutting down client handler")
return
}
}
}
func (b *MemoryBackend) continuousCleanup() {
id, shutdownRequested := shutdown.AddShutdownListener("MemoryBackend cleanup")
defer shutdown.RoutineDone(id)
for {
select {
case <-time.After(config.GetEmailTTL() / 4):
b.doCleanup()
case <-shutdownRequested:
log.Info("Shutting down memory cleanup with system")
return
case <-b.quit:
log.Info("Quitting memory cleanup")
return
}
}
}