hs-test: experimental support for multiple test instances

[vpp.git] / extras / hs-test / address_allocator.go

diff --git a/extras/hs-test/address_allocator.go b/extras/hs-test/address_allocator.go
index c08f889..72bc298 100644 (file)
--- a/extras/hs-test/address_allocator.go
+++ b/extras/hs-test/address_allocator.go
@@ -1,11 +1,20 @@
 package main
 
-import "fmt"
+import (
+       "errors"
+       "fmt"
+       "os"
+       "strings"
+
+       "github.com/edwarnicke/exechelper"
+)
 
 type AddressCounter = int
 
 type Ip4AddressAllocator struct {
        networks map[int]AddressCounter
+       chosenOctet int
+       assignedIps []string
 }
 
 func (a *Ip4AddressAllocator) AddNetwork(networkNumber int) {
@@ -28,12 +37,59 @@ func (a *Ip4AddressAllocator) NewIp4InterfaceAddress(inputNetworkNumber ...int)
                return "", fmt.Errorf("no available IPv4 addresses")
        }
 
-       address := fmt.Sprintf("10.10.%v.%v/24", networkNumber, numberOfAddresses)
+       address, err := a.createIpAddress(networkNumber, numberOfAddresses)
+
        a.networks[networkNumber] = numberOfAddresses + 1
 
+       return address + "/24", err
+}
+
+// Creates a file every time an IP is assigned: used to keep track of addresses in use.
+// If an address is not in use, 'counter' is then copied to 'chosenOctet' and it is used for the remaining tests.
+// Also checks host IP addresses.
+func (a *Ip4AddressAllocator) createIpAddress(networkNumber int, numberOfAddresses int) (string, error){
+       hostIps, _ := exechelper.CombinedOutput("ip a")
+       counter := 10
+       var address string
+
+       for {
+               if a.chosenOctet != 0 {
+                       address = fmt.Sprintf("10.%v.%v.%v", a.chosenOctet, networkNumber, numberOfAddresses)
+                       file, err := os.Create(address)
+                       if err != nil{
+                               return "", errors.New("unable to create file: " + fmt.Sprint(err))
+                       }
+                       file.Close()
+                       break
+               } else {
+                       address = fmt.Sprintf("10.%v.%v.%v", counter, networkNumber, numberOfAddresses)
+                       _, err := os.Stat(address)
+                       if err == nil || strings.Contains(string(hostIps), address) {
+                               counter++
+                       } else if os.IsNotExist(err) {
+                               file, err := os.Create(address)
+                                       if err != nil{
+                                       return "", errors.New("unable to create file: " + fmt.Sprint(err))
+                                       }
+                               file.Close()
+                               a.chosenOctet = counter
+                               break
+                       } else {
+                               return "", errors.New("an error occured while checking if a file exists: " + fmt.Sprint(err))
+                       }
+               }
+       }
+
+       a.assignedIps = append(a.assignedIps, address)
        return address, nil
 }
 
+func (a *Ip4AddressAllocator) deleteIpAddresses(){
+       for ip := range a.assignedIps{
+               os.Remove(a.assignedIps[ip])
+       }
+}
+
 func NewIp4AddressAllocator() *Ip4AddressAllocator {
        var ip4AddrAllocator = new(Ip4AddressAllocator)
        ip4AddrAllocator.networks = make(map[int]AddressCounter)