aghnet: imp docs and logging

internal/aghnet/systemresolvers.go

@@ -18,13 +18,13 @@ type HostGenFunc func() (host string)
 // unit is an alias for an existing map value.
 type unit = struct{}
 
-// SystemResolvers provides methods to deal with local resolvers provided by
-// system.
+// SystemResolvers helps to work with local resolvers' addresses provided by OS.
 type SystemResolvers interface {
-	// Get implements SystemResolvers interface for *systemResolvers.  It is
-	// safe for concurrent use.
+	// Get returns the slice of local resolvers' addresses.
+	// It should be safe for concurrent use.
 	Get() (rs []string)
-	// Refresh refreshes the local resolvers' addresses cache.
+	// Refresh refreshes the local resolvers' addresses cache.  It should be
+	// safe for concurrent use.
 	Refresh() (err error)
 }
 
@@ -49,7 +49,7 @@ func refreshWithTicker(sr SystemResolvers, tickCh <-chan time.Time) {
 			continue
 		}
 
-		log.Debug("local addresses cache is refreshed")
+		log.Debug("systemResolvers: local addresses cache is refreshed")
 	}
 }
 

internal/aghnet/systemresolver_windows.go → internal/aghnet/systemresolvers_windows.go

@@ -74,13 +74,13 @@ func (sr *systemResolvers) getAddrs() (addrs []string, err error) {
 		defer func() {
 			derr := stdin.Close()
 			if derr != nil {
-				log.Error("closing stdin pipe: %s", derr)
+				log.Error("systemResolvers: closing stdin pipe: %s", derr)
 			}
 		}()
 
 		_, werr := io.WriteString(stdin, "exit")
 		if werr != nil {
-			log.Error("writing to command pipe: %s", werr)
+			log.Error("systemResolvers: writing to command pipe: %s", werr)
 		}
 	}()