Maint: port forwarding refactoring (#543)

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

internal/provider/utils/noportforward.go

@@ -2,17 +2,21 @@ package utils
 
 import (
 	"context"
+	"errors"
+	"fmt"
 	"net"
 	"net/http"
 
-	"github.com/qdm12/gluetun/internal/firewall"
 	"github.com/qdm12/golibs/logging"
 )
 
 type NoPortForwarder interface {
 	PortForward(ctx context.Context, client *http.Client,
-		pfLogger logging.Logger, gateway net.IP, portAllower firewall.PortAllower,
-		syncState func(port uint16) (pfFilepath string))
+		logger logging.Logger, gateway net.IP, serverName string) (
+		port uint16, err error)
+	KeepPortForward(ctx context.Context, client *http.Client,
+		logger logging.Logger, port uint16, gateway net.IP, serverName string) (
+		err error)
 }
 
 type NoPortForwarding struct {
@@ -25,8 +29,16 @@ func NewNoPortForwarding(providerName string) *NoPortForwarding {
 	}
 }
 
+var ErrPortForwardingNotSupported = errors.New("custom port forwarding obtention is not supported")
+
 func (n *NoPortForwarding) PortForward(ctx context.Context, client *http.Client,
-	pfLogger logging.Logger, gateway net.IP, portAllower firewall.PortAllower,
-	syncState func(port uint16) (pfFilepath string)) {
-	panic("custom port forwarding obtention is not supported for " + n.providerName)
+	logger logging.Logger, gateway net.IP, serverName string) (
+	port uint16, err error) {
+	return 0, fmt.Errorf("%w: for %s", ErrPortForwardingNotSupported, n.providerName)
+}
+
+func (n *NoPortForwarding) KeepPortForward(ctx context.Context, client *http.Client,
+	logger logging.Logger, port uint16, gateway net.IP, serverName string) (
+	err error) {
+	return fmt.Errorf("%w: for %s", ErrPortForwardingNotSupported, n.providerName)
 }