func()

in mount/mount_linux.go [403:453]

• 37 lines of code
• 10 McCabe index (conditional complexity)

func (mounter *SafeFormatAndMount) GetDiskFormat(disk string) (string, error) {
	args := []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", disk}
	klog.V(4).Infof("Attempting to determine if disk %q is formatted using blkid with args: (%v)", disk, args)
	dataOut, err := mounter.Exec.Command("blkid", args...).CombinedOutput()
	output := string(dataOut)
	klog.V(4).Infof("Output: %q, err: %v", output, err)

	if err != nil {
		if exit, ok := err.(utilexec.ExitError); ok {
			if exit.ExitStatus() == 2 {
				// Disk device is unformatted.
				// For `blkid`, if the specified token (TYPE/PTTYPE, etc) was
				// not found, or no (specified) devices could be identified, an
				// exit code of 2 is returned.
				return "", nil
			}
		}
		klog.Errorf("Could not determine if disk %q is formatted (%v)", disk, err)
		return "", err
	}

	var fstype, pttype string

	lines := strings.Split(output, "\n")
	for _, l := range lines {
		if len(l) <= 0 {
			// Ignore empty line.
			continue
		}
		cs := strings.Split(l, "=")
		if len(cs) != 2 {
			return "", fmt.Errorf("blkid returns invalid output: %s", output)
		}
		// TYPE is filesystem type, and PTTYPE is partition table type, according
		// to https://www.kernel.org/pub/linux/utils/util-linux/v2.21/libblkid-docs/.
		if cs[0] == "TYPE" {
			fstype = cs[1]
		} else if cs[0] == "PTTYPE" {
			pttype = cs[1]
		}
	}

	if len(pttype) > 0 {
		klog.V(4).Infof("Disk %s detected partition table type: %s", disk, pttype)
		// Returns a special non-empty string as filesystem type, then kubelet
		// will not format it.
		return "unknown data, probably partitions", nil
	}

	return fstype, nil
}