Implement write canceling in COBSFramer

internal/serial/seriallink.go

@@ -71,7 +71,7 @@ func (h *Handler) Run(ctx context.Context) error {
 
 	defer func() {
 		cancel()
-		h.logger.Info("context canceled waiting for shutdown of components")
+		h.logger.Info("context canceled, waiting for shutdown of components")
 		wg.Wait()
 		h.logger.Info("shutdown complete")
 	}()

pkg/protocol/protocol.go

@@ -510,12 +510,34 @@ func (c *COBSFramer) WriteFrames(ctx context.Context, writer io.Writer, frameCha
 
 			encoded := c.encoder.Encode(frame)
 
-			n, err := io.Copy(writer, bytes.NewReader(encoded))
+			err := c.writeRaw(ctx, writer, encoded)
 			if err != nil {
-				return fmt.Errorf("cold not write data: %w", err)
+				return err
 			}
+		}
+	}
+}
+
+func (c *COBSFramer) writeRaw(ctx context.Context, writer io.Writer, raw []byte) error {
+	errChan := make(chan error)
+
+	go func() {
+		n, err := io.Copy(writer, bytes.NewReader(raw))
+		if err != nil {
+			errChan <- fmt.Errorf("could not write data: %w", err)
 
-			c.logger.Tracef("wrote %d bytes", n)
+			return
 		}
+
+		c.logger.WithField("count", n).Tracef("wrote bytes")
+
+		close(errChan)
+	}()
+
+	select {
+	case <-ctx.Done():
+		return nil
+	case err := <-errChan:
+		return err
 	}
 }