func (h *IPRangeHolder) FindCountry(ip string) (string, error) {
v, err := util.IPv42Int(ip)
if nil != err {
log.Printf("Failed to convert ip to int for reason:%v\n", err)
return "", err
}
compare := func(i int) bool {
return h.ranges[i].Start > uint64(v) || h.ranges[i].Start <= uint64(v) && h.ranges[i].End >= uint64(v)
}
index := sort.Search(len(h.ranges), compare)
if index == len(h.ranges) {
return "", nil
}
if index > 0 {
if h.ranges[index].Start > uint64(v) || h.ranges[index].End < uint64(v) {
return "", nil
}
return h.ranges[index].Country, nil
}
return "", fmt.Errorf("No record found.")
}
func ParseApnic(name string) (*IPRangeHolder, error) {
var file *os.File
var err error
if file, err = os.Open(name); err != nil {
return nil, err
}
reader := bufio.NewReader(file)
var buffer bytes.Buffer
var (
part []byte
prefix bool
)
holder := new(IPRangeHolder)
for {
if part, prefix, err = reader.ReadLine(); err != nil {
break
}
buffer.Write(part)
if !prefix {
line := buffer.String()
buffer.Reset()
sp := strings.Split(line, "|")
if len(sp) >= 6 {
if sp[1] == "CN" && sp[2] == "ipv4" {
startip, _ := util.IPv42Int(sp[3])
ipcount, _ := strconv.ParseUint(sp[4], 10, 32)
tmp := &IPRange{uint64(startip), uint64(startip) + uint64(ipcount-1), sp[1]}
holder.ranges = append(holder.ranges, tmp)
}
}
}
}
file.Close()
holder.sort()
return holder, nil
}