Implement review suggestions

resolver/resolve.go

@@ -32,8 +32,6 @@ var (
 	ErrFailure = errors.New("query failed")
 	// ErrContinue is returned when the resolver has no answer, and the next resolver should be asked
 	ErrContinue = errors.New("resolver has no answer")
-	// ErrCancelled is returned when the request was cancelled.
-	ErrCancelled = errors.New("request cancelled")
 	// ErrShuttingDown is returned when the resolver is shutting down.
 	ErrShuttingDown = errors.New("resolver is shutting down")
 
@@ -370,7 +368,9 @@ resolveLoop:
 					resolver.Conn.ReportFailure()
 					log.Tracer(ctx).Debugf("resolver: query to %s timed out", resolver.Info.ID())
 					continue
-				case errors.Is(err, ErrCancelled):
+				case errors.Is(err, context.Canceled):
+					return nil, err
+				case errors.Is(err, context.DeadlineExceeded):
 					return nil, err
 				case errors.Is(err, ErrShuttingDown):
 					return nil, err

resolver/resolver-mdns.go

@@ -419,7 +419,7 @@ func queryMulticastDNS(ctx context.Context, q *Query) (*RRCache, error) {
 			return rrCache, nil
 		}
 	case <-ctx.Done():
-		return nil, ErrCancelled
+		return nil, ctx.Err()
 	}
 
 	// Respond with NXDomain.

resolver/resolver-tcp.go

@@ -118,7 +118,7 @@ func (tr *TCPResolver) getOrCreateResolverConn(ctx context.Context) (*tcpResolve
 		case <-time.After(heartbeatTimeout):
 			log.Warningf("resolver: heartbeat for dns client %s failed", tr.resolver.Info.DescriptiveName())
 		case <-ctx.Done():
-			return nil, ErrCancelled
+			return nil, ctx.Err()
 		case <-module.Stopping():
 			return nil, ErrShuttingDown
 		}
@@ -189,7 +189,7 @@ func (tr *TCPResolver) Query(ctx context.Context, q *Query) (*RRCache, error) {
 	select {
 	case resolverConn.queries <- tq:
 	case <-ctx.Done():
-		return nil, ErrCancelled
+		return nil, ctx.Err()
 	case <-module.Stopping():
 		return nil, ErrShuttingDown
 	case <-time.After(defaultRequestTimeout):
@@ -201,7 +201,7 @@ func (tr *TCPResolver) Query(ctx context.Context, q *Query) (*RRCache, error) {
 	select {
 	case reply = <-tq.Response:
 	case <-ctx.Done():
-		return nil, ErrCancelled
+		return nil, ctx.Err()
 	case <-module.Stopping():
 		return nil, ErrShuttingDown
 	case <-time.After(defaultRequestTimeout):