[CI] Added linters

Now the CI will also run golangci-lint

Signed-off-by: Andrea Barberio <insomniac@slackware.it>

12 files changed, 45 insertions, 30 deletions

diff --git a/dhcpv4/async/client.go b/dhcpv4/async/client.go
index 4c2d3c1..54b500d 100644
--- a/dhcpv4/async/client.go
+++ b/dhcpv4/async/client.go
@@ -3,6 +3,7 @@ package async
 import (
 	"context"
 	"fmt"
+	"log"
 	"net"
 	"sync"
 	"time"
@@ -138,14 +139,18 @@ func (c *Client) send(packet *dhcpv4.DHCPv4) {
 
 	raddr, err := c.remoteAddr()
 	if err != nil {
-		p.Reject(err)
+		_ = p.Reject(err)
 		return
 	}
 
-	c.connection.SetWriteDeadline(time.Now().Add(c.WriteTimeout))
+	if err := c.connection.SetWriteDeadline(time.Now().Add(c.WriteTimeout)); err != nil {
+		log.Printf("Warning: cannot set write deadline: %v", err)
+		return
+	}
 	_, err = c.connection.WriteTo(packet.ToBytes(), raddr)
 	if err != nil {
-		p.Reject(err)
+		_ = p.Reject(err)
+		log.Printf("Warning: cannot write to %s: %v", raddr, err)
 		return
 	}
 
@@ -158,7 +163,10 @@ func (c *Client) receive(_ *dhcpv4.DHCPv4) {
 		received *dhcpv4.DHCPv4
 	)
 
-	c.connection.SetReadDeadline(time.Now().Add(c.ReadTimeout))
+	if err := c.connection.SetReadDeadline(time.Now().Add(c.ReadTimeout)); err != nil {
+		log.Printf("Warning: cannot set write deadline: %v", err)
+		return
+	}
 	for {
 		buffer := make([]byte, client4.MaxUDPReceivedPacketSize)
 		n, _, _, _, err := c.connection.ReadMsgUDP(buffer, oobdata)
@@ -177,7 +185,7 @@ func (c *Client) receive(_ *dhcpv4.DHCPv4) {
 	c.packetsLock.Lock()
 	if p, ok := c.packets[received.TransactionID]; ok {
 		delete(c.packets, received.TransactionID)
-		p.Resolve(received)
+		_ = p.Resolve(received)
 	}
 	c.packetsLock.Unlock()
 }
diff --git a/dhcpv4/async/client_test.go b/dhcpv4/async/client_test.go
index b134afe..2269d57 100644
--- a/dhcpv4/async/client_test.go
+++ b/dhcpv4/async/client_test.go
@@ -26,7 +26,9 @@ func serve(ctx context.Context, addr *net.UDPAddr, response *dhcpv4.DHCPv4) erro
 			case <-ctx.Done():
 				return
 			default:
-				conn.SetReadDeadline(time.Now().Add(1 * time.Second))
+				if err := conn.SetReadDeadline(time.Now().Add(1 * time.Second)); err != nil {
+					panic(err)
+				}
 				n, _, _, src, err := conn.ReadMsgUDP(buffer, oobdata)
 				if err != nil {
 					continue
@@ -35,7 +37,9 @@ func serve(ctx context.Context, addr *net.UDPAddr, response *dhcpv4.DHCPv4) erro
 				if err != nil {
 					continue
 				}
-				conn.SetWriteDeadline(time.Now().Add(1 * time.Second))
+				if err := conn.SetWriteDeadline(time.Now().Add(1 * time.Second)); err != nil {
+					panic(err)
+				}
 				_, err = conn.WriteTo(response.ToBytes(), src)
 				if err != nil {
 					continue
diff --git a/dhcpv4/bsdp/bsdp.go b/dhcpv4/bsdp/bsdp.go
index c9f7c26..d90e884 100644
--- a/dhcpv4/bsdp/bsdp.go
+++ b/dhcpv4/bsdp/bsdp.go
@@ -93,7 +93,7 @@ func NewInformListForInterface(ifname string, replyPort uint16) (*Packet, error)
 	if err != nil {
 		return nil, fmt.Errorf("could not get local IPv4 addr for %s: %v", iface.Name, err)
 	}
-	if localIPs == nil || len(localIPs) == 0 {
+	if len(localIPs) == 0 {
 		return nil, fmt.Errorf("could not get local IPv4 addr for %s", iface.Name)
 	}
 	return NewInformList(iface.HardwareAddr, localIPs[0], replyPort)
diff --git a/dhcpv4/bsdp/bsdp_option_misc_test.go b/dhcpv4/bsdp/bsdp_option_misc_test.go
index 44e2813..675a5db 100644
--- a/dhcpv4/bsdp/bsdp_option_misc_test.go
+++ b/dhcpv4/bsdp/bsdp_option_misc_test.go
@@ -22,7 +22,7 @@ func TestGetReplyPort(t *testing.T) {
 	require.Equal(t, uint16(1234), port)
 
 	o = VendorOptions{dhcpv4.Options{}}
-	port, err = o.ReplyPort()
+	_, err = o.ReplyPort()
 	require.Error(t, err, "no reply port present")
 }
 
@@ -40,7 +40,7 @@ func TestGetServerPriority(t *testing.T) {
 	require.Equal(t, uint16(1234), prio)
 
 	o = VendorOptions{dhcpv4.Options{}}
-	prio, err = o.ServerPriority()
+	_, err = o.ServerPriority()
 	require.Error(t, err, "no server prio present")
 }
 
@@ -73,19 +73,19 @@ func TestGetVersion(t *testing.T) {
 	require.Equal(t, ver, Version1_1)
 
 	o = VendorOptions{dhcpv4.Options{}}
-	ver, err = o.Version()
+	_, err = o.Version()
 	require.Error(t, err, "no version present")
 
 	o = VendorOptions{dhcpv4.Options{OptionVersion.Code(): []byte{}}}
-	ver, err = o.Version()
+	_, err = o.Version()
 	require.Error(t, err, "empty version field")
 
 	o = VendorOptions{dhcpv4.Options{OptionVersion.Code(): []byte{1}}}
-	ver, err = o.Version()
+	_, err = o.Version()
 	require.Error(t, err, "version option too short")
 
 	o = VendorOptions{dhcpv4.Options{OptionVersion.Code(): []byte{1, 2, 3}}}
-	ver, err = o.Version()
+	_, err = o.Version()
 	require.Error(t, err, "version option too long")
 }
 
diff --git a/dhcpv4/bsdp/option_vendor_specific_information.go b/dhcpv4/bsdp/option_vendor_specific_information.go
index abdd9a5..4c2365c 100644
--- a/dhcpv4/bsdp/option_vendor_specific_information.go
+++ b/dhcpv4/bsdp/option_vendor_specific_information.go
@@ -153,5 +153,5 @@ func parseOption(code dhcpv4.OptionCode, data []byte) fmt.Stringer {
 	if d != nil && d.FromBytes(data) == nil {
 		return d
 	}
-	return dhcpv4.OptionGeneric{data}
+	return dhcpv4.OptionGeneric{Data: data}
 }
diff --git a/dhcpv4/dhcpv4.go b/dhcpv4/dhcpv4.go
index cfb2f9a..b15c9e2 100644
--- a/dhcpv4/dhcpv4.go
+++ b/dhcpv4/dhcpv4.go
@@ -33,10 +33,10 @@ const (
 	// minPacketLen is the minimum DHCP header length.
 	minPacketLen = 236
 
-	// Maximum length of the ClientHWAddr (client hardware address) according to
-	// RFC 2131, Section 2. This is the link-layer destination a server
-	// must send responses to.
-	maxHWAddrLen = 16
+	// MaxHWAddrLen is the maximum hardware address length of the ClientHWAddr
+	// (client hardware address) according to RFC 2131, Section 2. This is the
+	// link-layer destination a server must send responses to.
+	MaxHWAddrLen = 16
 
 	// MaxMessageSize is the maximum size in bytes that a DHCPv4 packet can hold.
 	MaxMessageSize = 576
diff --git a/dhcpv4/dhcpv4_test.go b/dhcpv4/dhcpv4_test.go
index 8d6ec54..996b481 100644
--- a/dhcpv4/dhcpv4_test.go
+++ b/dhcpv4/dhcpv4_test.go
@@ -216,13 +216,14 @@ func TestDHCPv4NewRequestFromOffer(t *testing.T) {
 	require.NoError(t, err)
 	offer.SetBroadcast()
 	offer.UpdateOption(OptMessageType(MessageTypeOffer))
-	req, err := NewRequestFromOffer(offer)
+	_, err = NewRequestFromOffer(offer)
 	require.Error(t, err)
 
 	// Now add the option so it doesn't error out.
 	offer.UpdateOption(OptServerIdentifier(net.IPv4(192, 168, 0, 1)))
 
 	// Broadcast request
+	var req *DHCPv4
 	req, err = NewRequestFromOffer(offer)
 	require.NoError(t, err)
 	require.Equal(t, MessageTypeRequest, req.MessageType())
diff --git a/dhcpv4/nclient4/client_test.go b/dhcpv4/nclient4/client_test.go
index 6d7da1f..274c94b 100644
--- a/dhcpv4/nclient4/client_test.go
+++ b/dhcpv4/nclient4/client_test.go
@@ -37,7 +37,7 @@ func (h *handler) handle(conn net.PacketConn, peer net.Addr, m *dhcpv4.DHCPv4) {
 
 	if len(h.responses) > 0 {
 		for _, resp := range h.responses[0] {
-			conn.WriteTo(resp.ToBytes(), peer)
+			_, _ = conn.WriteTo(resp.ToBytes(), peer)
 		}
 		h.responses = h.responses[1:]
 	}
@@ -65,7 +65,9 @@ func serveAndClient(ctx context.Context, responses [][]*dhcpv4.DHCPv4, opts ...C
 	if err != nil {
 		panic(err)
 	}
-	go s.Serve()
+	go func() {
+		_ = s.Serve()
+	}()
 
 	return mc, serverConn
 }
@@ -77,7 +79,7 @@ func ComparePacket(got *dhcpv4.DHCPv4, want *dhcpv4.DHCPv4) error {
 	if (want == nil || got == nil) && (got != want) {
 		return fmt.Errorf("packet got %v, want %v", got, want)
 	}
-	if bytes.Compare(got.ToBytes(), want.ToBytes()) != 0 {
+	if !bytes.Equal(got.ToBytes(), want.ToBytes()) {
 		return fmt.Errorf("packet got %v, want %v", got, want)
 	}
 	return nil
@@ -266,8 +268,8 @@ func TestSimpleSendAndReadDiscardGarbage(t *testing.T) {
 	defer mc.Close()
 
 	// Too short for valid DHCPv4 packet.
-	udpConn.WriteTo([]byte{0x01}, nil)
-	udpConn.WriteTo([]byte{0x01, 0x2}, nil)
+	_, _ = udpConn.WriteTo([]byte{0x01}, nil)
+	_, _ = udpConn.WriteTo([]byte{0x01, 0x2}, nil)
 
 	rcvd, err := mc.SendAndRead(ctx, DefaultServers, pkt, nil)
 	if err != nil {
diff --git a/dhcpv4/option_ip_address_lease_time.go b/dhcpv4/option_ip_address_lease_time.go
index 20ee2b8..9bc8156 100644
--- a/dhcpv4/option_ip_address_lease_time.go
+++ b/dhcpv4/option_ip_address_lease_time.go
@@ -1,7 +1,6 @@
 package dhcpv4
 
 import (
-	"fmt"
 	"time"
 
 	"github.com/u-root/u-root/pkg/uio"
@@ -27,7 +26,7 @@ func (d Duration) ToBytes() []byte {
 
 // String returns a human-readable string for this option.
 func (d Duration) String() string {
-	return fmt.Sprintf("%s", time.Duration(d))
+	return time.Duration(d).String()
 }
 
 // OptIPAddressLeaseTime returns a new IP address lease time option.
diff --git a/dhcpv4/options.go b/dhcpv4/options.go
index 37607b7..11db5f7 100644
--- a/dhcpv4/options.go
+++ b/dhcpv4/options.go
@@ -175,7 +175,7 @@ func (o Options) sortedKeys() []int {
 		codes = append(codes, int(k))
 	}
 
-	sort.Sort(sort.IntSlice(codes))
+	sort.Ints(codes)
 	return codes
 }
 
diff --git a/dhcpv4/server4/server_test.go b/dhcpv4/server4/server_test.go
index cd46774..d24d49b 100644
--- a/dhcpv4/server4/server_test.go
+++ b/dhcpv4/server4/server_test.go
@@ -77,7 +77,9 @@ func setUpClientAndServer(t *testing.T, iface net.Interface, handler Handler) (*
 	if err != nil {
 		t.Fatal(err)
 	}
-	go s.Serve()
+	go func() {
+		_ = s.Serve()
+	}()
 
 	clientConn, err := nclient4.NewIPv4UDPConn("", caddr.Port)
 	if err != nil {
diff --git a/dhcpv4/ztpv4/parse_circuitid_test.go b/dhcpv4/ztpv4/parse_circuitid_test.go
index b075a16..94061c4 100644
--- a/dhcpv4/ztpv4/parse_circuitid_test.go
+++ b/dhcpv4/ztpv4/parse_circuitid_test.go
@@ -45,7 +45,6 @@ func TestFormatCircuitID(t *testing.T) {
 		name    string
 		circuit *CircuitID
 		want    string
-		fail    bool
 	}{
 		{name: "empty", circuit: &CircuitID{}, want: ",,,,"},
 		{name: "juniperQFX pattern", circuit: &CircuitID{Slot: "0", Module: "0", Port: "0", SubPort: "0"}, want: "0,0,0,0,"},