extras/hs-test/address_allocator.go

   1 package main
   2
   3 import "fmt"
   4
   5 type AddressCounter = int
   6
   7 type Ip4AddressAllocator struct {
   8         networks map[int]AddressCounter
   9 }
  10
  11 func (a *Ip4AddressAllocator) AddNetwork(networkNumber int) {
  12         a.networks[networkNumber] = 1
  13 }
  14
  15 func (a *Ip4AddressAllocator) NewIp4InterfaceAddress(inputNetworkNumber ...int) (string, error) {
  16         var networkNumber int = 0
  17         if len(inputNetworkNumber) > 0 {
  18                 networkNumber = inputNetworkNumber[0]
  19         }
  20
  21         if _, ok := a.networks[networkNumber]; !ok {
  22                 a.AddNetwork(networkNumber)
  23         }
  24
  25         numberOfAddresses := a.networks[networkNumber]
  26
  27         if numberOfAddresses == 254 {
  28                 return "", fmt.Errorf("no available IPv4 addresses")
  29         }
  30
  31         address := fmt.Sprintf("10.10.%v.%v/24", networkNumber, numberOfAddresses)
  32         a.networks[networkNumber] = numberOfAddresses + 1
  33
  34         return address, nil
  35 }
  36
  37 func NewIp4AddressAllocator() *Ip4AddressAllocator {
  38         var ip4AddrAllocator = new(Ip4AddressAllocator)
  39         ip4AddrAllocator.networks = make(map[int]AddressCounter)
  40         ip4AddrAllocator.AddNetwork(0)
  41         return ip4AddrAllocator
  42 }