Update CI configs to v0.12.1

.golangci.yml

@@ -41,6 +41,7 @@ linters:
     - maintidx         # maintidx measures the maintainability index of each function.
     - makezero         # Finds slice declarations with non-zero initial length
     - misspell         # Finds commonly misspelled English words in comments
+    - modernize        # Replace and suggests simplifications to code
     - nakedret         # Finds naked returns in functions greater than a specified function length
     - nestif           # Reports deeply nested if statements
     - nilerr           # Finds the code that returns nil even if it checks that the error is not nil.

errors.go

@@ -13,6 +13,7 @@ var (
 	errBadFirstPacket           = errors.New("rtcp: first packet in compound must be SR or RR")
 	errMissingCNAME             = errors.New("rtcp: compound missing SourceDescription with CNAME")
 	errPacketBeforeCNAME        = errors.New("rtcp: feedback packet seen before CNAME")
+	errTooManySSRCs             = errors.New("rtcp: too many SSRCs")
 	errTooManyReports           = errors.New("rtcp: too many reports")
 	errTooManyChunks            = errors.New("rtcp: too many chunks")
 	errTooManySources           = errors.New("rtcp: too many sources")

extended_report_test.go

@@ -229,7 +229,7 @@ func TestEncode(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, len(expected), len(rawPacket), "Encoded message length does not match expected length")
 
-	for i := 0; i < len(rawPacket); i++ {
+	for i := range rawPacket {
 		assert.Equalf(t, expected[i], rawPacket[i], "Byte %d of encoded packet does not match", i)
 	}
 }

full_intra_request.go

@@ -6,6 +6,7 @@ package rtcp
 import (
 	"encoding/binary"
 	"fmt"
+	"strings"
 )
 
 // A FIREntry is a (SSRC, seqno) pair, as carried by FullIntraRequest.
@@ -99,13 +100,14 @@ func (p *FullIntraRequest) MarshalSize() int {
 }
 
 func (p *FullIntraRequest) String() string {
-	out := fmt.Sprintf("FullIntraRequest %x %x",
+	var out strings.Builder
+	fmt.Fprintf(&out, "FullIntraRequest %x %x",
 		p.SenderSSRC, p.MediaSSRC)
 	for _, e := range p.FIR {
-		out += fmt.Sprintf(" (%x %v)", e.SSRC, e.SequenceNumber)
+		fmt.Fprintf(&out, " (%x %v)", e.SSRC, e.SequenceNumber)
 	}
 
-	return out
+	return out.String()
 }
 
 // DestinationSSRC returns an array of SSRC values that this packet refers to.

goodbye.go

@@ -6,6 +6,7 @@ package rtcp
 import (
 	"encoding/binary"
 	"fmt"
+	"strings"
 )
 
 // The Goodbye packet indicates that one or more sources are no longer active.
@@ -154,11 +155,12 @@ func (g *Goodbye) DestinationSSRC() []uint32 {
 }
 
 func (g Goodbye) String() string {
-	out := "Goodbye\n"
+	var out strings.Builder
+	out.WriteString("Goodbye\n")
 	for i, s := range g.Sources {
-		out += fmt.Sprintf("\tSource %d: %x\n", i, s)
+		fmt.Fprintf(&out, "\tSource %d: %x\n", i, s)
 	}
-	out += fmt.Sprintf("\tReason: %s\n", g.Reason)
+	fmt.Fprintf(&out, "\tReason: %s\n", g.Reason)
 
-	return out
+	return out.String()
 }

goodbye_test.go

@@ -4,6 +4,7 @@
 package rtcp
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -125,13 +126,13 @@ func TestGoodbyeUnmarshal(t *testing.T) {
 func TestGoodbyeRoundTrip(t *testing.T) {
 	// a slice with enough sources to overflow an 5-bit int
 	var tooManySources []uint32
-	var tooLongText string
+	var tooLongText strings.Builder
 
-	for i := 0; i < (1 << 5); i++ {
+	for range 1 << 5 {
 		tooManySources = append(tooManySources, 0x00)
 	}
-	for i := 0; i < (1 << 8); i++ {
-		tooLongText += "x"
+	for range 1 << 8 {
+		tooLongText.WriteString("x")
 	}
 
 	for _, test := range []struct {
@@ -187,7 +188,7 @@ func TestGoodbyeRoundTrip(t *testing.T) {
 			Name: "reason too long",
 			Bye: Goodbye{
 				Sources: []uint32{},
-				Reason:  tooLongText,
+				Reason:  tooLongText.String(),
 			},
 			WantError: errReasonTooLong,
 		},

packet_buffer.go

@@ -61,7 +61,7 @@ func (b *packetBuffer) write(v any) error {
 			return errWrongMarshalSize
 		}
 		if value.CanInterface() {
-			b.bytes[0] = byte(value.Uint())
+			b.bytes[0] = byte(value.Uint()) //nolint:gosec //  value.Kind() == reflect.Uint8 guarantees range
 		}
 		b.bytes = b.bytes[1:]
 	case reflect.Uint16:
@@ -109,7 +109,7 @@ func (b *packetBuffer) write(v any) error {
 					return err
 				}
 			} else {
-				advance := int(value.Field(i).Type().Size())
+				advance := int(value.Field(i).Type().Size()) //nolint:gosec // RTCP struct field sizes are small and controlled
 				if len(b.bytes) < advance {
 					return errWrongMarshalSize
 				}
@@ -200,7 +200,7 @@ func (b *packetBuffer) read(v any) error {
 					return err
 				}
 			} else {
-				advance := int(value.Field(i).Type().Size())
+				advance := int(value.Field(i).Type().Size()) //nolint:gosec //Size comes from type system and is bounded
 				if len(b.bytes) < advance {
 					return errWrongMarshalSize
 				}
@@ -245,7 +245,7 @@ func wireSize(v any) int {
 			if value.Index(i).CanInterface() {
 				size += wireSize(value.Index(i).Interface())
 			} else {
-				size += int(value.Index(i).Type().Size())
+				size += int(value.Index(i).Type().Size()) //nolint:gosec //  RTCP element sizes are small and bounded
 			}
 		}
 
@@ -258,12 +258,12 @@ func wireSize(v any) int {
 			if value.Field(i).CanInterface() {
 				size += wireSize(value.Field(i).Interface())
 			} else {
-				size += int(value.Field(i).Type().Size())
+				size += int(value.Field(i).Type().Size()) // nolint:gosec // Size comes from type system and is bounded
 			}
 		}
 
 	default:
-		size = int(value.Type().Size())
+		size = int(value.Type().Size()) // nolint:gosec // Size comes from type system and is bounde
 	}
 
 	return size

packet_stringifier.go

@@ -45,7 +45,7 @@ func formatField(name string, format string, f any, indent string) string {
 		return fmt.Sprintf("%s%s: <nil>\n", out, name)
 	}
 
-	isPacket := reflect.TypeOf(f).Implements(reflect.TypeOf((*Packet)(nil)).Elem())
+	isPacket := reflect.TypeOf(f).Implements(reflect.TypeFor[Packet]())
 
 	// Resolve pointers to their underlying values
 	if value.Type().Kind() == reflect.Ptr && !value.IsNil() {

receiver_estimated_maximum_bitrate.go

@@ -91,7 +91,11 @@ func (p ReceiverEstimatedMaximumBitrate) MarshalTo(buf []byte) (n int, err error
 	buf[15] = 'B'
 
 	// Write the length of the ssrcs to follow at the end
-	buf[16] = byte(len(p.SSRCs))
+	if len(p.SSRCs) > math.MaxUint8 {
+		return 0, errTooManySSRCs
+	}
+
+	buf[16] = byte(len(p.SSRCs)) //nolint:gosec // length validated above
 
 	exp := 0
 	bitrate := p.Bitrate
@@ -118,9 +122,9 @@ func (p ReceiverEstimatedMaximumBitrate) MarshalTo(buf []byte) (n int, err error
 	// We can't quite use the binary package because
 	// a) it's a uint24 and b) the exponent is only 6-bits
 	// Just trust me; this is big-endian encoding.
-	buf[17] = byte(exp<<2) | byte(mantissa>>16)
-	buf[18] = byte(mantissa >> 8)
-	buf[19] = byte(mantissa)
+	buf[17] = byte(exp<<2) | byte(mantissa>>16) //nolint: gosec //  mantissa is limited to 18 bits
+	buf[18] = byte(mantissa >> 8)               //nolint: gosec //  mantissa is limited to 18 bits
+	buf[19] = byte(mantissa)                    // nolint: gosec //  mantissa is limited to 18 bits
 
 	// Write the SSRCs at the very end.
 	n = 20

receiver_report.go

@@ -6,6 +6,7 @@ package rtcp
 import (
 	"encoding/binary"
 	"fmt"
+	"strings"
 )
 
 // A ReceiverReport (RR) packet provides reception quality feedback for an RTP stream.
@@ -188,12 +189,13 @@ func (r *ReceiverReport) DestinationSSRC() []uint32 {
 }
 
 func (r ReceiverReport) String() string {
-	out := fmt.Sprintf("ReceiverReport from %x\n", r.SSRC)
-	out += "\tSSRC    \tLost\tLastSequence\n"
+	var out strings.Builder
+	fmt.Fprintf(&out, "ReceiverReport from %x\n", r.SSRC)
+	out.WriteString("\tSSRC    \tLost\tLastSequence\n")
 	for _, i := range r.Reports {
-		out += fmt.Sprintf("\t%x\t%d/%d\t%d\n", i.SSRC, i.FractionLost, i.TotalLost, i.LastSequenceNumber)
+		fmt.Fprintf(&out, "\t%x\t%d/%d\t%d\n", i.SSRC, i.FractionLost, i.TotalLost, i.LastSequenceNumber)
 	}
-	out += fmt.Sprintf("\tProfile Extension Data: %v\n", r.ProfileExtensions)
+	fmt.Fprintf(&out, "\tProfile Extension Data: %v\n", r.ProfileExtensions)
 
-	return out
+	return out.String()
 }

receiver_report_test.go

@@ -169,7 +169,7 @@ func TestReceiverReportUnmarshal(t *testing.T) {
 func tooManyReports() []ReceptionReport {
 	// a slice with enough ReceptionReports to overflow an 5-bit int
 	var tooManyReports []ReceptionReport
-	for i := 0; i < (1 << 5); i++ {
+	for range 1 << 5 {
 		tooManyReports = append(tooManyReports, ReceptionReport{
 			SSRC:               2,
 			FractionLost:       2,

rfc8888.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"strings"
 )
 
 // https://www.rfc-editor.org/rfc/rfc8888.html#name-rtcp-congestion-control-fee
@@ -164,16 +165,17 @@ func (b CCFeedbackReport) Marshal() ([]byte, error) {
 }
 
 func (b CCFeedbackReport) String() string {
-	out := fmt.Sprintf("CCFB:\n\tHeader %v\n", b.Header())
-	out += fmt.Sprintf("CCFB:\n\tSender SSRC %d\n", b.SenderSSRC)
-	out += fmt.Sprintf("\tReport Timestamp %d\n", b.ReportTimestamp)
-	out += "\tFeedback Reports \n"
+	var out strings.Builder
+	fmt.Fprintf(&out, "CCFB:\n\tHeader %v\n", b.Header())
+	fmt.Fprintf(&out, "CCFB:\n\tSender SSRC %d\n", b.SenderSSRC)
+	fmt.Fprintf(&out, "\tReport Timestamp %d\n", b.ReportTimestamp)
+	out.WriteString("\tFeedback Reports \n")
 	for _, report := range b.ReportBlocks {
-		out += fmt.Sprintf("%v ", report)
+		fmt.Fprintf(&out, "%v ", report)
 	}
-	out += "\n"
+	out.WriteString("\n")
 
-	return out
+	return out.String()
 }
 
 // Unmarshal decodes the Congestion Control Feedback Report from binary.
@@ -237,22 +239,21 @@ func (b *CCFeedbackReportBlock) len() int {
 }
 
 func (b CCFeedbackReportBlock) String() string {
-	out := fmt.Sprintf("\tReport Block Media SSRC %d\n", b.MediaSSRC)
-	out += fmt.Sprintf("\tReport Begin Sequence Nr %d\n", b.BeginSequence)
-	out += fmt.Sprintf("\tReport length %d\n\t", len(b.MetricBlocks))
+	var out strings.Builder
+	fmt.Fprintf(&out, "\tReport Block Media SSRC %d\n", b.MediaSSRC)
+	fmt.Fprintf(&out, "\tReport Begin Sequence Nr %d\n", b.BeginSequence)
+	fmt.Fprintf(&out, "\tReport length %d\n\t", len(b.MetricBlocks))
 	for i, block := range b.MetricBlocks {
 		//nolint:gosec // G115
-		out += fmt.Sprintf(
-			"{nr: %d, rx: %v, ts: %v, ecn: %v} ",
+		fmt.Fprintf(&out, "{nr: %d, rx: %v, ts: %v, ecn: %v} ",
 			b.BeginSequence+uint16(i),
 			block.Received,
 			block.ArrivalTimeOffset,
-			block.ECN,
-		)
+			block.ECN)
 	}
-	out += "\n"
+	out.WriteString("\n")
 
-	return out
+	return out.String()
 }
 
 // marshal encodes the Congestion Control Feedback Report Block in binary.
@@ -301,7 +302,7 @@ func (b *CCFeedbackReportBlock) unmarshal(rawPacket []byte) error {
 	}
 
 	b.MetricBlocks = make([]CCFeedbackMetricBlock, numReports)
-	for i := int(0); i < numReports; i++ {
+	for i := range numReports {
 		var mb CCFeedbackMetricBlock
 		offset := reportsOffset + 2*i
 		if err := mb.unmarshal(rawPacket[offset : offset+2]); err != nil {

rfc8888_test.go

@@ -74,7 +74,6 @@ func TestCCFeedbackMetricBlockUnmarshalMarshal(t *testing.T) {
 			},
 		},
 	} {
-		test := test
 		t.Run(fmt.Sprintf("Unmarshal-%v", test.Name), func(t *testing.T) {
 			var block CCFeedbackMetricBlock
 			err := block.unmarshal(test.Data)
@@ -112,7 +111,6 @@ func TestCCFeedbackMetricBlockUnmarshalMarshal(t *testing.T) {
 			},
 		},
 	} {
-		test := test
 		t.Run(fmt.Sprintf("Unmarshal-%v", test.Name), func(t *testing.T) {
 			var block CCFeedbackMetricBlock
 			err := block.unmarshal(test.Data)
@@ -122,7 +120,6 @@ func TestCCFeedbackMetricBlockUnmarshalMarshal(t *testing.T) {
 	}
 
 	for _, l := range []int{0, 1, 3} {
-		l := l
 		t.Run(fmt.Sprintf("shortMetricBlock-%v", l), func(t *testing.T) {
 			var block CCFeedbackMetricBlock
 			data := make([]byte, l)
@@ -248,7 +245,6 @@ func TestCCFeedbackReportBlockUnmarshalMarshal(t *testing.T) {
 			},
 		},
 	} {
-		test := test
 		t.Run(fmt.Sprintf("Unmarshal-%v", test.Name), func(t *testing.T) {
 			var block CCFeedbackReportBlock
 			err := block.unmarshal(test.Data)
@@ -409,7 +405,6 @@ func TestCCFeedbackReportUnmarshalMarshal(t *testing.T) {
 			},
 		},
 	} {
-		test := test
 		t.Run(fmt.Sprintf("Unmarshal-%v", test.Name), func(t *testing.T) {
 			pkts, err := Unmarshal(test.Data)
 			assert.NoError(t, err)

sender_report.go

@@ -6,6 +6,7 @@ package rtcp
 import (
 	"encoding/binary"
 	"fmt"
+	"strings"
 )
 
 // A SenderReport (SR) packet provides reception quality feedback for an RTP stream.
@@ -249,17 +250,18 @@ func (r *SenderReport) Header() Header {
 }
 
 func (r SenderReport) String() string {
-	out := fmt.Sprintf("SenderReport from %x\n", r.SSRC)
-	out += fmt.Sprintf("\tNTPTime:\t%d\n", r.NTPTime)
-	out += fmt.Sprintf("\tRTPTIme:\t%d\n", r.RTPTime)
-	out += fmt.Sprintf("\tPacketCount:\t%d\n", r.PacketCount)
-	out += fmt.Sprintf("\tOctetCount:\t%d\n", r.OctetCount)
+	var out strings.Builder
+	fmt.Fprintf(&out, "SenderReport from %x\n", r.SSRC)
+	fmt.Fprintf(&out, "\tNTPTime:\t%d\n", r.NTPTime)
+	fmt.Fprintf(&out, "\tRTPTIme:\t%d\n", r.RTPTime)
+	fmt.Fprintf(&out, "\tPacketCount:\t%d\n", r.PacketCount)
+	fmt.Fprintf(&out, "\tOctetCount:\t%d\n", r.OctetCount)
 
-	out += "\tSSRC    \tLost\tLastSequence\n"
+	out.WriteString("\tSSRC    \tLost\tLastSequence\n")
 	for _, i := range r.Reports {
-		out += fmt.Sprintf("\t%x\t%d/%d\t%d\n", i.SSRC, i.FractionLost, i.TotalLost, i.LastSequenceNumber)
+		fmt.Fprintf(&out, "\t%x\t%d/%d\t%d\n", i.SSRC, i.FractionLost, i.TotalLost, i.LastSequenceNumber)
 	}
-	out += fmt.Sprintf("\tProfile Extension Data: %v\n", r.ProfileExtensions)
+	fmt.Fprintf(&out, "\tProfile Extension Data: %v\n", r.ProfileExtensions)
 
-	return out
+	return out.String()
 }