*: fix golangci-lint warnings

dhcpd/dhcpd.go

@@ -227,7 +227,7 @@ func (s *Server) Start() error {
 
 	// TODO: don't close if interface and addresses are the same
 	if s.conn != nil {
-		s.closeConn()
+		_ = s.closeConn()
 	}
 
 	iface, err := net.InterfaceByName(s.conf.InterfaceName)
@@ -251,7 +251,7 @@ func (s *Server) Start() error {
 		if err != nil && !s.stopping {
 			log.Printf("dhcp4.Serve() returned with error: %s", err)
 		}
-		c.Close() // in case Serve() exits for other reason than listening socket closure
+		_ = c.Close() // in case Serve() exits for other reason than listening socket closure
 		s.running = false
 		s.cond.Signal()
 	}()
@@ -609,10 +609,10 @@ func (s *Server) handleDecline(p dhcp4.Packet, options dhcp4.Options) dhcp4.Pack
 // AddStaticLease adds a static lease (thread-safe)
 func (s *Server) AddStaticLease(l Lease) error {
 	if len(l.IP) != 4 {
-		return fmt.Errorf("Invalid IP")
+		return fmt.Errorf("invalid IP")
 	}
 	if len(l.HWAddr) != 6 {
-		return fmt.Errorf("Invalid MAC")
+		return fmt.Errorf("invalid MAC")
 	}
 	l.Expiry = time.Unix(leaseExpireStatic, 0)
 
@@ -637,9 +637,9 @@ func (s *Server) AddStaticLease(l Lease) error {
 func (s *Server) rmDynamicLeaseWithIP(ip net.IP) error {
 	var newLeases []*Lease
 	for _, lease := range s.leases {
-		if bytes.Equal(lease.IP.To4(), ip) {
+		if net.IP.Equal(lease.IP.To4(), ip) {
 			if lease.Expiry.Unix() == leaseExpireStatic {
-				return fmt.Errorf("Static lease with the same IP already exists")
+				return fmt.Errorf("static lease with the same IP already exists")
 			}
 			continue
 		}
@@ -654,7 +654,7 @@ func (s *Server) rmDynamicLeaseWithIP(ip net.IP) error {
 func (s *Server) rmLease(l Lease) error {
 	var newLeases []*Lease
 	for _, lease := range s.leases {
-		if bytes.Equal(lease.IP.To4(), l.IP) {
+		if net.IP.Equal(lease.IP.To4(), l.IP) {
 			if !bytes.Equal(lease.HWAddr, l.HWAddr) ||
 				lease.Hostname != l.Hostname {
 				return fmt.Errorf("Lease not found")
@@ -671,17 +671,17 @@ func (s *Server) rmLease(l Lease) error {
 // RemoveStaticLease removes a static lease (thread-safe)
 func (s *Server) RemoveStaticLease(l Lease) error {
 	if len(l.IP) != 4 {
-		return fmt.Errorf("Invalid IP")
+		return fmt.Errorf("invalid IP")
 	}
 	if len(l.HWAddr) != 6 {
-		return fmt.Errorf("Invalid MAC")
+		return fmt.Errorf("invalid MAC")
 	}
 
 	s.leasesLock.Lock()
 
 	if s.findReservedHWaddr(l.IP) == nil {
 		s.leasesLock.Unlock()
-		return fmt.Errorf("Lease not found")
+		return fmt.Errorf("lease not found")
 	}
 
 	err := s.rmLease(l)

dhcpd/network_utils.go

@@ -33,7 +33,7 @@ func HasStaticIP(ifaceName string) (bool, error) {
 		return hasStaticIPDarwin(ifaceName)
 	}
 
-	return false, fmt.Errorf("Cannot check if IP is static: not supported on %s", runtime.GOOS)
+	return false, fmt.Errorf("cannot check if IP is static: not supported on %s", runtime.GOOS)
 }
 
 // Set a static IP for the specified network interface
@@ -46,7 +46,7 @@ func SetStaticIP(ifaceName string) error {
 		return setStaticIPDarwin(ifaceName)
 	}
 
-	return fmt.Errorf("Cannot set static IP on %s", runtime.GOOS)
+	return fmt.Errorf("cannot set static IP on %s", runtime.GOOS)
 }
 
 // for dhcpcd.conf
@@ -114,7 +114,7 @@ func getGatewayIP(ifaceName string) string {
 func setStaticIPDhcpdConf(ifaceName string) error {
 	ip := util.GetSubnet(ifaceName)
 	if len(ip) == 0 {
-		return errors.New("Can't get IP address")
+		return errors.New("can't get IP address")
 	}
 
 	ip4, _, err := net.ParseCIDR(ip)
@@ -198,7 +198,7 @@ func setStaticIPDarwin(ifaceName string) error {
 		return err
 	}
 	if code != 0 {
-		return fmt.Errorf("Failed to set DNS servers, code=%d", code)
+		return fmt.Errorf("failed to set DNS servers, code=%d", code)
 	}
 
 	// Actually configures hardware port to have static IP
@@ -208,7 +208,7 @@ func setStaticIPDarwin(ifaceName string) error {
 		return err
 	}
 	if code != 0 {
-		return fmt.Errorf("Failed to set DNS servers, code=%d", code)
+		return fmt.Errorf("failed to set DNS servers, code=%d", code)
 	}
 
 	return nil
@@ -220,7 +220,7 @@ func getCurrentHardwarePortInfo(ifaceName string) (hardwarePortInfo, error) {
 	m := getNetworkSetupHardwareReports()
 	hardwarePort, ok := m[ifaceName]
 	if !ok {
-		return hardwarePortInfo{}, fmt.Errorf("Could not find hardware port for %s", ifaceName)
+		return hardwarePortInfo{}, fmt.Errorf("could not find hardware port for %s", ifaceName)
 	}
 
 	return getHardwarePortInfo(hardwarePort)
@@ -274,7 +274,7 @@ func getHardwarePortInfo(hardwarePort string) (hardwarePortInfo, error) {
 
 	match := re.FindStringSubmatch(out)
 	if len(match) == 0 {
-		return h, errors.New("Could not find hardware port info")
+		return h, errors.New("could not find hardware port info")
 	}
 
 	h.name = hardwarePort
@@ -300,7 +300,7 @@ func getEtcResolvConfServers() ([]string, error) {
 
 	matches := re.FindAllStringSubmatch(string(body), -1)
 	if len(matches) == 0 {
-		return nil, errors.New("Found no DNS servers in /etc/resolv.conf")
+		return nil, errors.New("found no DNS servers in /etc/resolv.conf")
 	}
 
 	addrs := make([]string, 0)

dhcpd/standalone/main.go

@@ -80,7 +80,7 @@ func main() {
 		panic(err)
 	}
 	log.Printf("Now serving DHCP")
-	signalChannel := make(chan os.Signal)
+	signalChannel := make(chan os.Signal, 1)
 	signal.Notify(signalChannel, syscall.SIGINT, syscall.SIGTERM)
 	<-signalChannel