package system import ( "bufio" "fmt" "os" "strings" "golang.org/x/sys/unix" ) type diskInfoCache struct { udevDataPath string values map[string]string } var udevPath = "/run/udev/data" func (s *DiskIOStats) diskInfo(devName string) (map[string]string, error) { var err error var stat unix.Stat_t path := "/dev/" + devName err = unix.Stat(path, &stat) if err != nil { return nil, err } if s.infoCache == nil { s.infoCache = map[string]diskInfoCache{} } ic, ok := s.infoCache[devName] if ok { return ic.values, nil } major := stat.Rdev >> 8 & 0xff minor := stat.Rdev & 0xff udevDataPath := fmt.Sprintf("%s/b%d:%d", udevPath, major, minor) di := map[string]string{} s.infoCache[devName] = diskInfoCache{ udevDataPath: udevDataPath, values: di, } f, err := os.Open(udevDataPath) if err != nil { return nil, err } defer f.Close() scnr := bufio.NewScanner(f) for scnr.Scan() { l := scnr.Text() if len(l) < 4 || l[:2] != "E:" { continue } kv := strings.SplitN(l[2:], "=", 2) if len(kv) < 2 { continue } di[kv[0]] = kv[1] } return di, nil }