capture: disable without cgo

capture/capture.go

@@ -1,3 +1,5 @@
+//go:build cgo
+
 package capture
 
 import (

capture/netgo.go

@@ -0,0 +1,16 @@
+//go:build !cgo
+
+package capture
+
+import "fmt"
+
+import "inet.af/netaddr"
+
+type nullReaderFromCloser interface {
+	ReadFrom(b []byte) (body []byte, src netaddr.IP, ifindex int, err error)
+	Close() error
+}
+
+func FromInterface(string) (nullReaderFromCloser, error) {
+	return nil, fmt.Errorf("packet capture disabled")
+}