package qemu import ( "context" "fmt" "log" "math/rand" "net" "github.com/hashicorp/packer/helper/multistep" "github.com/hashicorp/packer/packer" ) // This step configures the VM to enable the VNC server. // // Uses: // config *config // ui packer.Ui // // Produces: // vnc_port uint - The port that VNC is configured to listen on. type stepConfigureVNC struct{} func (stepConfigureVNC) Run(_ context.Context, state multistep.StateBag) multistep.StepAction { config := state.Get("config").(*Config) ui := state.Get("ui").(packer.Ui) // Find an open VNC port. Note that this can still fail later on // because we have to release the port at some point. But this does its // best. msg := fmt.Sprintf("Looking for available port between %d and %d on %s", config.VNCPortMin, config.VNCPortMax, config.VNCBindAddress) ui.Say(msg) log.Print(msg) var vncPort uint portRange := int(config.VNCPortMax - config.VNCPortMin) for { if portRange > 0 { vncPort = uint(rand.Intn(portRange)) + config.VNCPortMin } else { vncPort = config.VNCPortMin } log.Printf("Trying port: %d", vncPort) l, err := net.Listen("tcp", fmt.Sprintf("%s:%d", config.VNCBindAddress, vncPort)) if err == nil { defer l.Close() break } } log.Printf("Found available VNC port: %d on IP: %s", vncPort, config.VNCBindAddress) state.Put("vnc_port", vncPort) state.Put("vnc_ip", config.VNCBindAddress) return multistep.ActionContinue } func (stepConfigureVNC) Cleanup(multistep.StateBag) {}