Maint: port forwarding refactoring (#543)

- portforward package
- portforward run loop
- Less functional arguments and cycles

internal/openvpn/state/portforwarded.go

@@ -1,26 +0,0 @@
-package state
-
-type PortForwardedGetterSetter interface {
-	PortForwardedGetter
-	SetPortForwarded(port uint16)
-}
-
-type PortForwardedGetter interface {
-	GetPortForwarded() (port uint16)
-}
-
-// GetPortForwarded is used by the control HTTP server
-// to obtain the port currently forwarded.
-func (s *State) GetPortForwarded() (port uint16) {
-	s.portForwardedMu.RLock()
-	defer s.portForwardedMu.RUnlock()
-	return s.portForwarded
-}
-
-// SetPortForwarded is only used from within the OpenVPN loop
-// to set the port forwarded.
-func (s *State) SetPortForwarded(port uint16) {
-	s.portForwardedMu.Lock()
-	defer s.portForwardedMu.Unlock()
-	s.portForwarded = port
-}

internal/openvpn/state/state.go

@@ -13,7 +13,6 @@ var _ Manager = (*State)(nil)
 type Manager interface {
 	SettingsGetSetter
 	ServersGetterSetter
-	PortForwardedGetterSetter
 	GetSettingsAndServers() (settings configuration.OpenVPN,
 		allServers models.AllServers)
 }
@@ -36,9 +35,6 @@ type State struct {
 
 	allServers   models.AllServers
 	allServersMu sync.RWMutex
-
-	portForwarded   uint16
-	portForwardedMu sync.RWMutex
 }
 
 func (s *State) GetSettingsAndServers() (settings configuration.OpenVPN,