Log gvproxy and server9 to file on log-level=debug

Logging to os.Stdout and os.Stderr does not seem to work in
Powershell. I am not entirely certain why.

Logfiles are the best alternative I can think of.

Signed-off-by: Matt Heon <mheon@redhat.com>

cmd/podman/machine/client9p.go

@@ -106,16 +106,12 @@ func client9p(portNum uint32, mountPath string) error {
 		cmd := exec.Command("mount", "-t", "9p", "-o", "trans=fd,rfdno=3,wfdno=3,version=9p2000.L", "9p", mountPath)
 		cmd.ExtraFiles = []*os.File{vsock}
 
-		err := cmd.Run()
-		output, outErr := cmd.CombinedOutput()
-		switch {
-		case outErr != nil:
-			logrus.Errorf("Unable to obtain output of mount command: %v", err)
-		case err == nil:
+		output, err := cmd.CombinedOutput()
+		if err != nil {
+			err = fmt.Errorf("running mount: %w\nOutput: %s", err, string(output))
+		} else {
 			logrus.Debugf("Mount output: %s", string(output))
 			logrus.Infof("Mounted directory %s using 9p", mountPath)
-		default:
-			err = fmt.Errorf("running mount: %w\nOutput: %s", err, string(output))
 		}
 
 		errChan <- err

pkg/machine/hyperv/machine.go

@@ -772,8 +772,9 @@ func (m *HyperVMachine) startHostNetworking() (string, machine.APIForwardingStat
 	c := cmd.Cmd(gvproxyBinary)
 
 	if logrus.IsLevelEnabled(logrus.DebugLevel) {
-		c.Stdout = os.Stdout
-		c.Stderr = os.Stderr
+		if err := logCommandToFile(c, "gvproxy.log"); err != nil {
+			return "", 0, err
+		}
 	}
 
 	logrus.Debugf("Starting gvproxy with command: %s %v", gvproxyBinary, c.Args)
@@ -809,8 +810,9 @@ func (m *HyperVMachine) startHostNetworking() (string, machine.APIForwardingStat
 	fsCmd := exec.Command(executable, args...)
 
 	if logrus.IsLevelEnabled(logrus.DebugLevel) {
-		fsCmd.Stdout = os.Stdout
-		fsCmd.Stderr = os.Stderr
+		if err := logCommandToFile(fsCmd, "podman-machine-server9.log"); err != nil {
+			return "", 0, err
+		}
 	}
 
 	if err := fsCmd.Start(); err != nil {
@@ -822,6 +824,25 @@ func (m *HyperVMachine) startHostNetworking() (string, machine.APIForwardingStat
 	return forwardSock, state, nil
 }
 
+func logCommandToFile(c *exec.Cmd, filename string) error {
+	dir, err := machine.GetDataDir(machine.HyperVVirt)
+	if err != nil {
+		return fmt.Errorf("obtain machine dir: %w", err)
+	}
+	path := filepath.Join(dir, filename)
+	logrus.Infof("Going to log to %s", path)
+	log, err := os.Create(path)
+	if err != nil {
+		return fmt.Errorf("create log file: %w", err)
+	}
+	defer log.Close()
+
+	c.Stdout = log
+	c.Stderr = log
+
+	return nil
+}
+
 func (m *HyperVMachine) setupAPIForwarding(cmd gvproxy.GvproxyCommand) (gvproxy.GvproxyCommand, string, machine.APIForwardingState) {
 	socket, err := m.forwardSocketPath()
 	if err != nil {