Fix linters

cmd/main.go

@@ -1,10 +1,12 @@
 // SPDX-FileCopyrightText: 2025 The Pion community <https://pion.ly>
 // SPDX-License-Identifier: MIT
 
+// Package main implements the entry point for the bandwidth estimation test tool.
 package main
 
 import (
 	"context"
+	"errors"
 	"flag"
 	"io"
 	"log"
@@ -35,11 +37,64 @@ func realMain() error {
 		return send(*addr, *rtpLogFile, *rtcpLogFile, *ccLogFile)
 	}
 
-	log.Fatalf("invalid mode: %s\n", *mode)
+	log.Fatalf("invalid mode: %s", *mode)
+
 	return nil
 }
 
 func receive(addr, rtpLogFile, rtcpLogFile string) error {
+	rcv, err := newReceiver(rtpLogFile, rtcpLogFile)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if err = rcv.Close(); err != nil {
+			log.Printf("failed to close receiver: %v", err)
+		}
+	}()
+
+	err = rcv.receiver.SetupPeerConnection()
+	if err != nil {
+		return err
+	}
+	http.Handle("/sdp", rcv.receiver.SDPHandler())
+
+	//nolint:gosec
+	return http.ListenAndServe(addr, nil)
+}
+
+type recv struct {
+	receiver   *receiver.Receiver
+	rtpLogger  io.WriteCloser
+	rtcpLogger io.WriteCloser
+}
+
+func (c recv) Close() error {
+	var errs []error
+
+	err := c.receiver.Close()
+	if err != nil {
+		errs = append(errs, err)
+	}
+
+	if c.rtpLogger != nil {
+		err = c.rtpLogger.Close()
+		if err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	if c.rtcpLogger != nil {
+		err = c.rtcpLogger.Close()
+		if err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	return errors.Join(errs...)
+}
+
+func newReceiver(rtpLogFile, rtcpLogFile string) (recv, error) {
 	options := []receiver.Option{
 		receiver.PacketLogWriter(os.Stdout, os.Stdout),
 		receiver.DefaultInterceptors(),
@@ -50,101 +105,143 @@ func receive(addr, rtpLogFile, rtcpLogFile string) error {
 	if rtpLogFile != "" {
 		rtpLogger, err = logging.GetLogFile(rtpLogFile)
 		if err != nil {
-			return err
+			return recv{}, err
 		}
-		defer rtpLogger.Close()
 	}
 	if rtcpLogFile != "" {
 		rtcpLogger, err = logging.GetLogFile(rtcpLogFile)
 		if err != nil {
-			return err
+			return recv{}, err
 		}
-		defer rtcpLogger.Close()
 	}
 	if rtpLogger != nil || rtcpLogger != nil {
 		options = append(options, receiver.PacketLogWriter(rtpLogger, rtcpLogger))
 	}
 	r, err := receiver.NewReceiver(options...)
+	if err != nil {
+		return recv{}, err
+	}
+
+	return recv{
+		receiver:   r,
+		rtpLogger:  rtpLogger,
+		rtcpLogger: rtcpLogger,
+	}, nil
+}
+
+func send(addr, rtpLogFile, rtcpLogFile, ccLogFile string) error {
+	snd, err := newSender(rtpLogFile, rtcpLogFile, ccLogFile)
 	if err != nil {
 		return err
 	}
-	err = r.SetupPeerConnection()
+	defer func() {
+		if err = snd.Close(); err != nil {
+			log.Printf("failed to close sender: %v", err)
+		}
+	}()
+
+	err = snd.sender.SetupPeerConnection()
 	if err != nil {
 		return err
 	}
-	http.Handle("/sdp", r.SDPHandler())
-	log.Fatal(http.ListenAndServe(addr, nil))
-	return nil
+	err = snd.sender.SignalHTTP(addr, "sdp")
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+
+	sigs := make(chan os.Signal, 1)
+	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
+	defer func() {
+		signal.Stop(sigs)
+		cancel()
+	}()
+	go func() {
+		select {
+		case <-sigs:
+			cancel()
+			log.Println("cancel called")
+		case <-ctx.Done():
+		}
+	}()
+
+	return snd.sender.Start(ctx)
 }
 
-func send(addr, rtpLogFile, rtcpLogFile, ccLogFile string) error {
+type sndr struct {
+	sender     *sender.Sender
+	rtpLogger  io.WriteCloser
+	rtcpLogger io.WriteCloser
+	ccLogger   io.WriteCloser
+}
+
+func (s sndr) Close() error {
+	var errs []error
+
+	err := s.rtpLogger.Close()
+	if err != nil {
+		errs = append(errs, err)
+	}
+
+	err = s.rtcpLogger.Close()
+	if err != nil {
+		errs = append(errs, err)
+	}
+
+	err = s.ccLogger.Close()
+	if err != nil {
+		errs = append(errs, err)
+	}
+
+	return errors.Join(errs...)
+}
+
+func newSender(rtpLogFile, rtcpLogFile, ccLogFile string) (sndr, error) {
 	options := []sender.Option{
 		sender.DefaultInterceptors(),
 		sender.GCC(initialBitrate),
 	}
 	var rtpLogger io.WriteCloser
 	var rtcpLogger io.WriteCloser
+	var ccLogger io.WriteCloser
 	var err error
 	if rtpLogFile != "" {
 		rtpLogger, err = logging.GetLogFile(rtpLogFile)
 		if err != nil {
-			return err
+			return sndr{}, err
 		}
-		defer rtpLogger.Close()
 	}
 	if rtcpLogFile != "" {
 		rtcpLogger, err = logging.GetLogFile(rtcpLogFile)
 		if err != nil {
-			return err
+			return sndr{}, err
 		}
-		defer rtcpLogger.Close()
 	}
 	if ccLogFile != "" {
-		var ccLogger io.WriteCloser
 		ccLogger, err = logging.GetLogFile(ccLogFile)
 		if err != nil {
-			return err
+			return sndr{}, err
 		}
-		defer ccLogger.Close()
 		options = append(options, sender.CCLogWriter(ccLogger))
 	}
 	if rtpLogger != nil || rtcpLogger != nil {
 		options = append(options, sender.PacketLogWriter(rtpLogger, rtcpLogger))
 	}
-	s, err := sender.NewSender(
+	snd, err := sender.NewSender(
 		sender.NewStatisticalEncoderSource(),
 		options...,
 	)
 	if err != nil {
-		return err
+		return sndr{}, err
 	}
-	err = s.SetupPeerConnection()
-	if err != nil {
-		return err
-	}
-	err = s.SignalHTTP(addr, "sdp")
-	if err != nil {
-		return err
-	}
-
-	ctx, cancel := context.WithCancel(context.Background())
-
-	sigs := make(chan os.Signal, 1)
-	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
-	defer func() {
-		signal.Stop(sigs)
-		cancel()
-	}()
-	go func() {
-		select {
-		case <-sigs:
-			cancel()
-			log.Println("cancel called")
-		case <-ctx.Done():
-		}
-	}()
 
-	return s.Start(ctx)
+	return sndr{
+		sender:     snd,
+		rtpLogger:  rtpLogger,
+		rtcpLogger: rtcpLogger,
+		ccLogger:   ccLogger,
+	}, nil
 }
 
 func main() {

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/pion/rtp v1.8.13
 	github.com/pion/transport/v3 v3.0.7
 	github.com/pion/webrtc/v4 v4.0.14
+	github.com/stretchr/testify v1.10.0
 	golang.org/x/sync v0.11.0
 )
 
@@ -24,12 +25,15 @@ require (
 )
 
 require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/pion/datachannel v1.5.10 // indirect
 	github.com/pion/randutil v0.1.0 // indirect
 	github.com/pion/sctp v1.8.37 // indirect
 	github.com/pion/sdp/v3 v3.0.11 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
 	golang.org/x/crypto v0.33.0 // indirect
 	golang.org/x/net v0.35.0 // indirect
 	golang.org/x/sys v0.30.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,8 +1,11 @@
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
 github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/pion/datachannel v1.5.10 h1:ly0Q26K1i6ZkGf42W7D4hQYR90pZwzFOjTq5AuCKk4o=
 github.com/pion/datachannel v1.5.10/go.mod h1:p/jJfC9arb29W7WrxyKbepTU20CFgyx5oLo8Rs4Py/M=
 github.com/pion/dtls/v3 v3.0.4 h1:44CZekewMzfrn9pmGrj5BNnTMDCFwr+6sLH+cCuLM7U=
@@ -36,7 +39,9 @@ github.com/pion/turn/v4 v4.0.0/go.mod h1:MuPDkm15nYSklKpN8vWJ9W2M0PlyQZqYt1McGux
 github.com/pion/webrtc/v4 v4.0.14 h1:nyds/sFRR+HvmWoBa6wrL46sSfpArE0qR883MBW96lg=
 github.com/pion/webrtc/v4 v4.0.14/go.mod h1:R3+qTnQTS03UzwDarYecgioNf7DYgTsldxnCXB821Kk=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/wlynxg/anet v0.0.5 h1:J3VJGi1gvo0JwZ/P1/Yc/8p63SoW98B5dHkYDmpgvvU=
 github.com/wlynxg/anet v0.0.5/go.mod h1:eay5PRQr7fIVAMbTbchTnO9gG65Hg/uYGdc7mguHxoA=
 golang.org/x/crypto v0.33.0 h1:IOBPskki6Lysi0lo9qQvbxiQ+FvsCC/YWOecCHAixus=
@@ -47,4 +52,7 @@ golang.org/x/sync v0.11.0 h1:GGz8+XQP4FvTTrjZPzNKTMFtSXH80RAzG+5ghFPgK9w=
 golang.org/x/sync v0.11.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.30.0 h1:QjkSwP/36a20jFYWkSue1YwXzLmsV5Gfq7Eiy72C1uc=
 golang.org/x/sys v0.30.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

internal/sequencenumber/unwrapper.go

@@ -0,0 +1,48 @@
+// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
+// SPDX-License-Identifier: MIT
+
+// Package sequencenumber provides a sequence number unwrapper
+package sequencenumber
+
+const (
+	maxSequenceNumberPlusOne = int64(65536)
+	breakpoint               = 32768 // half of max uint16
+)
+
+// Unwrapper stores an unwrapped sequence number.
+type Unwrapper struct {
+	init          bool
+	lastUnwrapped int64
+}
+
+func isNewer(value, previous uint16) bool {
+	if value-previous == breakpoint {
+		return value > previous
+	}
+
+	return value != previous && (value-previous) < breakpoint
+}
+
+// Unwrap unwraps the next sequencenumber.
+func (u *Unwrapper) Unwrap(i uint16) int64 {
+	if !u.init {
+		u.init = true
+		u.lastUnwrapped = int64(i)
+
+		return u.lastUnwrapped
+	}
+
+	lastWrapped := uint16(u.lastUnwrapped) //nolint:gosec // G115
+	delta := int64(i - lastWrapped)
+	if isNewer(i, lastWrapped) {
+		if delta < 0 {
+			delta += maxSequenceNumberPlusOne
+		}
+	} else if delta > 0 && u.lastUnwrapped+delta-maxSequenceNumberPlusOne >= 0 {
+		delta -= maxSequenceNumberPlusOne
+	}
+
+	u.lastUnwrapped += delta
+
+	return u.lastUnwrapped
+}