func portSetToDockerPorts(ports *schema.Set) (map[dc.Port]struct{}, map[dc.Port][]dc.PortBinding) {
	retExposedPorts := map[dc.Port]struct{}{}
	retPortBindings := map[dc.Port][]dc.PortBinding{}

	for _, portInt := range ports.List() {
		port := portInt.(map[string]interface{})
		internal := port["internal"].(int)
		protocol := port["protocol"].(string)

		exposedPort := dc.Port(strconv.Itoa(internal) + "/" + protocol)
		retExposedPorts[exposedPort] = struct{}{}

		external, extOk := port["external"].(int)
		ip, ipOk := port["ip"].(string)

		if extOk {
			portBinding := dc.PortBinding{
				HostPort: strconv.Itoa(external),
			}
			if ipOk {
				portBinding.HostIP = ip
			}
			retPortBindings[exposedPort] = append(retPortBindings[exposedPort], portBinding)
		}
	}

	return retExposedPorts, retPortBindings
}

func resourceAwsNetworkInterfaceDetach(oa *schema.Set, meta interface{}, eniId string) error {
	// if there was an old attachment, remove it
	if oa != nil && len(oa.List()) > 0 {
		old_attachment := oa.List()[0].(map[string]interface{})
		detach_request := &ec2.DetachNetworkInterfaceInput{
			AttachmentId: aws.String(old_attachment["attachment_id"].(string)),
			Force:        aws.Bool(true),
		}
		conn := meta.(*AWSClient).ec2conn
		_, detach_err := conn.DetachNetworkInterface(detach_request)
		if detach_err != nil {
			return fmt.Errorf("Error detaching ENI: %s", detach_err)
		}

		log.Printf("[DEBUG] Waiting for ENI (%s) to become dettached", eniId)
		stateConf := &resource.StateChangeConf{
			Pending: []string{"true"},
			Target:  "false",
			Refresh: networkInterfaceAttachmentRefreshFunc(conn, eniId),
			Timeout: 10 * time.Minute,
		}
		if _, err := stateConf.WaitForState(); err != nil {
			return fmt.Errorf(
				"Error waiting for ENI (%s) to become dettached: %s", eniId, err)
		}
	}

	return nil
}

func makeAwsStringSet(in *schema.Set) []*string {
	inList := in.List()
	ret := make([]*string, len(inList), len(inList))
	for i := 0; i < len(ret); i++ {
		ret[i] = aws.String(inList[i].(string))
	}
	return ret
}

func createChildHealthCheckList(s *schema.Set) (nl []*string) {
	l := s.List()
	for _, n := range l {
		nl = append(nl, aws.String(n.(string)))
	}

	return nl
}

func convertSetToList(s *schema.Set) (nl []*string) {
	l := s.List()
	for _, n := range l {
		nl = append(nl, aws.String(n.(string)))
	}

	return nl
}

func setToMapByKey(s *schema.Set, key string) map[string]interface{} {
	result := make(map[string]interface{})
	for _, rawData := range s.List() {
		data := rawData.(map[string]interface{})
		result[data[key].(string)] = data
	}

	return result
}

func stringSetToStringSlice(stringSet *schema.Set) []string {
	ret := []string{}
	if stringSet == nil {
		return ret
	}
	for _, envVal := range stringSet.List() {
		ret = append(ret, envVal.(string))
	}
	return ret
}

func extraHostsSetToDockerExtraHosts(extraHosts *schema.Set) []string {
	retExtraHosts := []string{}

	for _, hostInt := range extraHosts.List() {
		host := hostInt.(map[string]interface{})
		ip := host["ip"].(string)
		hostname := host["host"].(string)
		retExtraHosts = append(retExtraHosts, hostname+":"+ip)
	}

	return retExtraHosts
}

func ipamConfigSetToIpamConfigs(ipamConfigSet *schema.Set) []dc.IPAMConfig {
	ipamConfigs := make([]dc.IPAMConfig, ipamConfigSet.Len())

	for i, ipamConfigInt := range ipamConfigSet.List() {
		ipamConfigRaw := ipamConfigInt.(map[string]interface{})

		ipamConfig := dc.IPAMConfig{}
		ipamConfig.Subnet = ipamConfigRaw["subnet"].(string)
		ipamConfig.IPRange = ipamConfigRaw["ip_range"].(string)
		ipamConfig.Gateway = ipamConfigRaw["gateway"].(string)

		auxAddressRaw := ipamConfigRaw["aux_address"].(map[string]interface{})
		ipamConfig.AuxAddress = make(map[string]string, len(auxAddressRaw))
		for k, v := range auxAddressRaw {
			ipamConfig.AuxAddress[k] = v.(string)
		}

		ipamConfigs[i] = ipamConfig
	}

	return ipamConfigs
}

func volumeSetToDockerVolumes(volumes *schema.Set) (map[string]struct{}, []string, []string, error) {
	retVolumeMap := map[string]struct{}{}
	retHostConfigBinds := []string{}
	retVolumeFromContainers := []string{}

	for _, volumeInt := range volumes.List() {
		volume := volumeInt.(map[string]interface{})
		fromContainer := volume["from_container"].(string)
		containerPath := volume["container_path"].(string)
		volumeName := volume["volume_name"].(string)
		if len(volumeName) == 0 {
			volumeName = volume["host_path"].(string)
		}
		readOnly := volume["read_only"].(bool)

		switch {
		case len(fromContainer) == 0 && len(containerPath) == 0:
			return retVolumeMap, retHostConfigBinds, retVolumeFromContainers, errors.New("Volume entry without container path or source container")
		case len(fromContainer) != 0 && len(containerPath) != 0:
			return retVolumeMap, retHostConfigBinds, retVolumeFromContainers, errors.New("Both a container and a path specified in a volume entry")
		case len(fromContainer) != 0:
			retVolumeFromContainers = append(retVolumeFromContainers, fromContainer)
		case len(volumeName) != 0:
			readWrite := "rw"
			if readOnly {
				readWrite = "ro"
			}
			retVolumeMap[containerPath] = struct{}{}
			retHostConfigBinds = append(retHostConfigBinds, volumeName+":"+containerPath+":"+readWrite)
		default:
			retVolumeMap[containerPath] = struct{}{}
		}
	}

	return retVolumeMap, retHostConfigBinds, retVolumeFromContainers, nil
}

func deleteFirewallRules(
	d *schema.ResourceData,
	meta interface{},
	rules *schema.Set,
	ors *schema.Set) error {
	var errs *multierror.Error

	var wg sync.WaitGroup
	wg.Add(ors.Len())

	sem := make(chan struct{}, d.Get("parallelism").(int))
	for _, rule := range ors.List() {
		// Put a sleep here to avoid DoS'ing the API
		time.Sleep(500 * time.Millisecond)

		go func(rule map[string]interface{}) {
			defer wg.Done()
			sem <- struct{}{}

			// Delete a single rule
			err := deleteFirewallRule(d, meta, rule)

			// If we have at least one UUID, we need to save the rule
			if len(rule["uuids"].(map[string]interface{})) > 0 {
				rules.Add(rule)
			}

			if err != nil {
				errs = multierror.Append(errs, err)
			}

			<-sem
		}(rule.(map[string]interface{}))
	}

	wg.Wait()

	return errs.ErrorOrNil()
}

func deletePortForwards(
	d *schema.ResourceData,
	meta interface{},
	forwards *schema.Set,
	ors *schema.Set) error {
	var errs *multierror.Error

	var wg sync.WaitGroup
	wg.Add(ors.Len())

	sem := make(chan struct{}, 10)
	for _, forward := range ors.List() {
		// Put a sleep here to avoid DoS'ing the API
		time.Sleep(500 * time.Millisecond)

		go func(forward map[string]interface{}) {
			defer wg.Done()
			sem <- struct{}{}

			// Delete a single forward
			err := deletePortForward(d, meta, forward)

			// If we have a UUID, we need to save the forward
			if forward["uuid"].(string) != "" {
				forwards.Add(forward)
			}

			if err != nil {
				errs = multierror.Append(errs, err)
			}

			<-sem
		}(forward.(map[string]interface{}))
	}

	wg.Wait()

	return errs.ErrorOrNil()
}