Fix(fd): compile error

Author: xjasonlyu

core/device/fd/fd.go

@@ -1,41 +1,3 @@
 package fd
 
-import (
-	"fmt"
-	"strconv"
-
-	"github.com/xjasonlyu/tun2socks/core/device"
-	"golang.org/x/sys/unix"
-	"gvisor.dev/gvisor/pkg/tcpip/stack"
-)
-
 const Driver = "fd"
-
-type FD struct {
-	stack.LinkEndpoint
-
-	fd  int
-	mtu uint32
-}
-
-func Open(name string, mtu uint32) (device.Device, error) {
-	fd, err := strconv.Atoi(name)
-	if err != nil {
-		return nil, fmt.Errorf("cannot open fd: %s", name)
-	}
-	return open(fd, mtu)
-}
-
-func (f *FD) Type() string {
-	return Driver
-}
-
-func (f *FD) Name() string {
-	return strconv.Itoa(f.fd)
-}
-
-func (f *FD) Close() error {
-	return unix.Close(f.fd)
-}
-
-var _ device.Device = (*FD)(nil)

core/device/fd/fd_unix.go

@@ -0,0 +1,41 @@
+//go:build !windows
+
+package fd
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/xjasonlyu/tun2socks/core/device"
+	"golang.org/x/sys/unix"
+	"gvisor.dev/gvisor/pkg/tcpip/stack"
+)
+
+type FD struct {
+	stack.LinkEndpoint
+
+	fd  int
+	mtu uint32
+}
+
+func Open(name string, mtu uint32) (device.Device, error) {
+	fd, err := strconv.Atoi(name)
+	if err != nil {
+		return nil, fmt.Errorf("cannot open fd: %s", name)
+	}
+	return open(fd, mtu)
+}
+
+func (f *FD) Type() string {
+	return Driver
+}
+
+func (f *FD) Name() string {
+	return strconv.Itoa(f.fd)
+}
+
+func (f *FD) Close() error {
+	return unix.Close(f.fd)
+}
+
+var _ device.Device = (*FD)(nil)

core/device/fd/fd_windows.go

@@ -0,0 +1,11 @@
+package fd
+
+import (
+	"errors"
+
+	"github.com/xjasonlyu/tun2socks/core/device"
+)
+
+func Open(name string, mtu uint32) (device.Device, error) {
+	return nil, errors.New("not supported")
+}

core/device/fd/open_others.go

@@ -1,4 +1,4 @@
-//go:build !linux
+//go:build !linux && !windows
 
 package fd