func allocatePort(bnd *netutils.PortBinding, containerIP, defHostIP net.IP, ulPxyEnabled bool) error {
var (
host net.Addr
err error
)
// Store the container interface address in the operational binding
bnd.IP = containerIP
// Adjust the host address in the operational binding
if len(bnd.HostIP) == 0 {
bnd.HostIP = defHostIP
}
// Construct the container side transport address
container, err := bnd.ContainerAddr()
if err != nil {
return err
}
// Try up to maxAllocatePortAttempts times to get a port that's not already allocated.
for i := 0; i < maxAllocatePortAttempts; i++ {
if host, err = portMapper.Map(container, bnd.HostIP, int(bnd.HostPort), ulPxyEnabled); err == nil {
break
}
// There is no point in immediately retrying to map an explicitly chosen port.
if bnd.HostPort != 0 {
logrus.Warnf("Failed to allocate and map port %d: %s", bnd.HostPort, err)
break
}
logrus.Warnf("Failed to allocate and map port: %s, retry: %d", err, i+1)
}
if err != nil {
return err
}
// Save the host port (regardless it was or not specified in the binding)
switch netAddr := host.(type) {
case *net.TCPAddr:
bnd.HostPort = uint16(host.(*net.TCPAddr).Port)
return nil
case *net.UDPAddr:
bnd.HostPort = uint16(host.(*net.UDPAddr).Port)
return nil
default:
// For completeness
return ErrUnsupportedAddressType(fmt.Sprintf("%T", netAddr))
}
}
