func ParseMountInfo()

in mount_helper_unix.go [93:157]
59 lines of code
13 McCabe index (conditional complexity)

func ParseMountInfo(filename string) ([]MountInfo, error) {
	content, err := utilio.ConsistentRead(filename, maxListTries)
	if err != nil {
		return []MountInfo{}, err
	}
	contentStr := string(content)
	infos := []MountInfo{}

	for _, line := range strings.Split(contentStr, "\n") {
		if line == "" {
			// the last split() item is empty string following the last \n
			continue
		}
		// See `man proc` for authoritative description of format of the file.
		fields := strings.Fields(line)
		if len(fields) < expectedAtLeastNumFieldsPerMountInfo {
			return nil, fmt.Errorf("wrong number of fields in (expected at least %d, got %d): %s", expectedAtLeastNumFieldsPerMountInfo, len(fields), line)
		}
		id, err := strconv.Atoi(fields[0])
		if err != nil {
			return nil, err
		}
		parentID, err := strconv.Atoi(fields[1])
		if err != nil {
			return nil, err
		}
		mm := strings.Split(fields[2], ":")
		if len(mm) != 2 {
			return nil, fmt.Errorf("parsing '%s' failed: unexpected minor:major pair %s", line, mm)
		}
		major, err := strconv.Atoi(mm[0])
		if err != nil {
			return nil, fmt.Errorf("parsing '%s' failed: unable to parse major device id, err:%v", mm[0], err)
		}
		minor, err := strconv.Atoi(mm[1])
		if err != nil {
			return nil, fmt.Errorf("parsing '%s' failed: unable to parse minor device id, err:%v", mm[1], err)
		}

		info := MountInfo{
			ID:           id,
			ParentID:     parentID,
			Major:        major,
			Minor:        minor,
			Root:         fields[3],
			MountPoint:   fields[4],
			MountOptions: strings.Split(fields[5], ","),
		}
		// All fields until "-" are "optional fields".
		i := 6
		for ; i < len(fields) && fields[i] != "-"; i++ {
			info.OptionalFields = append(info.OptionalFields, fields[i])
		}
		// Parse the rest 3 fields.
		i++
		if len(fields)-i < 3 {
			return nil, fmt.Errorf("expect 3 fields in %s, got %d", line, len(fields)-i)
		}
		info.FsType = fields[i]
		info.Source = fields[i+1]
		info.SuperOptions = strings.Split(fields[i+2], ",")
		infos = append(infos, info)
	}
	return infos, nil
}