From 58fe1cfe77d18347b4a6f4cd19964c487db2a403 Mon Sep 17 00:00:00 2001
From: aler9 <46489434+aler9@users.noreply.github.com>
Date: Thu, 5 Nov 2020 12:30:25 +0100
Subject: [PATCH] add docs

---
 README.md                           |  2 +-
 internal/client/client.go           | 40 +++++++++++++--------
 internal/clientman/clientman.go     |  9 +++++
 internal/conf/conf.go               |  2 ++
 internal/conf/pathconf.go           |  2 ++
 internal/conf/utils.go              |  1 +
 internal/confenv/confenv.go         |  1 +
 internal/confwatcher/confwatcher.go |  4 +++
 internal/externalcmd/externalcmd.go |  4 +++
 internal/loghandler/loghandler.go   |  9 +++++
 internal/metrics/metrics.go         |  4 +++
 internal/path/path.go               | 56 ++++++++++++++++++++---------
 internal/path/readersmap.go         | 10 +++---
 internal/pathman/pathman.go         | 12 +++++++
 internal/pprof/pprof.go             |  6 ++++
 internal/servertcp/server.go        |  5 +++
 internal/serverudp/server.go        |  9 +++++
 internal/sourcertmp/source.go       |  6 ++++
 internal/sourcertsp/source.go       |  6 ++++
 internal/stats/stats.go             |  2 ++
 internal/syslog/syslog_unix.go      |  3 ++
 internal/syslog/syslog_win.go       |  3 ++
 main.go                             |  1 +
 23 files changed, 160 insertions(+), 37 deletions(-)

diff --git a/README.md b/README.md
index 646542d5..d8146b0c 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@
 [![Go Report Card](https://goreportcard.com/badge/github.com/aler9/rtsp-simple-server)](https://goreportcard.com/report/github.com/aler9/rtsp-simple-server)
 [![Docker Hub](https://img.shields.io/badge/docker-aler9%2Frtsp--simple--server-blue)](https://hub.docker.com/r/aler9/rtsp-simple-server)
 
-_rtsp-simple-server_ is a simple, ready-to-use and zero-dependency RTSP server and RTSP proxy, a software that allows multiple users to publish and read live video and audio streams over time. RTSP is a standard protocol that describes how to perform these operations with the help of a server, that is contacted by both readers and publishers and relays the publisher streams to the readers.
+_rtsp-simple-server_ is a simple, ready-to-use and zero-dependency RTSP server and RTSP proxy, a software that allows multiple users to publish, read and proxy live video and audio streams over time. RTSP is a standard protocol that describes how to perform these operations with the help of a server, that is contacted by both publishers and readers and relays the publisher's streams to the readers.
 
 Features:
 * Read and publish live streams with UDP and TCP
diff --git a/internal/client/client.go b/internal/client/client.go
index 2795ab69..06aa778e 100644
--- a/internal/client/client.go
+++ b/internal/client/client.go
@@ -78,6 +78,7 @@ func (cs state) String() string {
 	return "Invalid"
 }
 
+// Path is implemented by path.Path.
 type Path interface {
 	Name() string
 	SourceTrackCount() int
@@ -88,6 +89,7 @@ type Path interface {
 	OnFrame(int, gortsplib.StreamType, []byte)
 }
 
+// Parent is implemented by clientman.ClientMan.
 type Parent interface {
 	Log(string, ...interface{})
 	OnClientClose(*Client)
@@ -96,6 +98,7 @@ type Parent interface {
 	OnClientSetupPlay(*Client, string, int, *base.Request) (Path, error)
 }
 
+// Client is a RTSP client.
 type Client struct {
 	rtspPort            int
 	readTimeout         time.Duration
@@ -128,6 +131,7 @@ type Client struct {
 	terminate    chan struct{}
 }
 
+// New allocates a Client.
 func New(
 	rtspPort int,
 	readTimeout time.Duration,
@@ -174,11 +178,13 @@ func New(
 	return c
 }
 
+// Close closes a Client.
 func (c *Client) Close() {
 	atomic.AddInt64(c.stats.CountClients, -1)
 	close(c.terminate)
 }
 
+// IsSource implementes path.source.
 func (c *Client) IsSource() {}
 
 func (c *Client) log(format string, args ...interface{}) {
@@ -240,22 +246,23 @@ func (c *Client) writeResError(cseq base.HeaderValue, code base.StatusCode, err
 	})
 }
 
-type ErrAuthNotCritical struct {
+type errAuthNotCritical struct {
 	*base.Response
 }
 
-func (ErrAuthNotCritical) Error() string {
+func (errAuthNotCritical) Error() string {
 	return "auth not critical"
 }
 
-type ErrAuthCritical struct {
+type errAuthCritical struct {
 	*base.Response
 }
 
-func (ErrAuthCritical) Error() string {
+func (errAuthCritical) Error() string {
 	return "auth critical"
 }
 
+// Authenticate performs an authentication.
 func (c *Client) Authenticate(authMethods []headers.AuthMethod, ips []interface{}, user string, pass string, req *base.Request) error {
 	// validate ip
 	if ips != nil {
@@ -264,7 +271,7 @@ func (c *Client) Authenticate(authMethods []headers.AuthMethod, ips []interface{
 		if !ipEqualOrInRange(ip, ips) {
 			c.log("ERR: ip '%s' not allowed", ip)
 
-			return ErrAuthCritical{&base.Response{
+			return errAuthCritical{&base.Response{
 				StatusCode: base.StatusUnauthorized,
 				Header: base.Header{
 					"CSeq":             req.Header["CSeq"],
@@ -296,7 +303,7 @@ func (c *Client) Authenticate(authMethods []headers.AuthMethod, ips []interface{
 			if c.authFailures > 3 {
 				c.log("ERR: unauthorized: %s", err)
 
-				return ErrAuthCritical{&base.Response{
+				return errAuthCritical{&base.Response{
 					StatusCode: base.StatusUnauthorized,
 					Header: base.Header{
 						"CSeq":             req.Header["CSeq"],
@@ -309,7 +316,7 @@ func (c *Client) Authenticate(authMethods []headers.AuthMethod, ips []interface{
 					c.log("WARN: unauthorized: %s", err)
 				}
 
-				return ErrAuthNotCritical{&base.Response{
+				return errAuthNotCritical{&base.Response{
 					StatusCode: base.StatusUnauthorized,
 					Header: base.Header{
 						"CSeq":             req.Header["CSeq"],
@@ -382,11 +389,11 @@ func (c *Client) handleRequest(req *base.Request) error {
 		path, err := c.parent.OnClientDescribe(c, basePath, req)
 		if err != nil {
 			switch terr := err.(type) {
-			case ErrAuthNotCritical:
+			case errAuthNotCritical:
 				c.conn.WriteResponse(terr.Response)
 				return nil
 
-			case ErrAuthCritical:
+			case errAuthCritical:
 				c.conn.WriteResponse(terr.Response)
 				return errRunTerminate
 
@@ -441,11 +448,11 @@ func (c *Client) handleRequest(req *base.Request) error {
 		path, err := c.parent.OnClientAnnounce(c, basePath, tracks, req)
 		if err != nil {
 			switch terr := err.(type) {
-			case ErrAuthNotCritical:
+			case errAuthNotCritical:
 				c.conn.WriteResponse(terr.Response)
 				return nil
 
-			case ErrAuthCritical:
+			case errAuthCritical:
 				c.conn.WriteResponse(terr.Response)
 				return errRunTerminate
 
@@ -534,11 +541,11 @@ func (c *Client) handleRequest(req *base.Request) error {
 				path, err := c.parent.OnClientSetupPlay(c, basePath, trackId, req)
 				if err != nil {
 					switch terr := err.(type) {
-					case ErrAuthNotCritical:
+					case errAuthNotCritical:
 						c.conn.WriteResponse(terr.Response)
 						return nil
 
-					case ErrAuthCritical:
+					case errAuthCritical:
 						c.conn.WriteResponse(terr.Response)
 						return errRunTerminate
 
@@ -592,11 +599,11 @@ func (c *Client) handleRequest(req *base.Request) error {
 				path, err := c.parent.OnClientSetupPlay(c, basePath, trackId, req)
 				if err != nil {
 					switch terr := err.(type) {
-					case ErrAuthNotCritical:
+					case errAuthNotCritical:
 						c.conn.WriteResponse(terr.Response)
 						return nil
 
-					case ErrAuthCritical:
+					case errAuthCritical:
 						c.conn.WriteResponse(terr.Response)
 						return errRunTerminate
 
@@ -1288,6 +1295,7 @@ func (c *Client) runRecordTCP() {
 	}
 }
 
+// OnUdpPublisherFrame implements serverudp.Publisher.
 func (c *Client) OnUdpPublisherFrame(trackId int, streamType base.StreamType, buf []byte) {
 	atomic.StoreInt64(c.udpLastFrameTimes[trackId], time.Now().Unix())
 
@@ -1295,6 +1303,7 @@ func (c *Client) OnUdpPublisherFrame(trackId int, streamType base.StreamType, bu
 	c.path.OnFrame(trackId, streamType, buf)
 }
 
+// OnReaderFrame implements path.Reader.
 func (c *Client) OnReaderFrame(trackId int, streamType base.StreamType, buf []byte) {
 	track, ok := c.streamTracks[trackId]
 	if !ok {
@@ -1326,6 +1335,7 @@ func (c *Client) OnReaderFrame(trackId int, streamType base.StreamType, buf []by
 	}
 }
 
+// OnPathDescribeData is called by path.Path.
 func (c *Client) OnPathDescribeData(sdp []byte, redirect string, err error) {
 	c.describeData <- describeData{sdp, redirect, err}
 }
diff --git a/internal/clientman/clientman.go b/internal/clientman/clientman.go
index 55707d9a..163227c8 100644
--- a/internal/clientman/clientman.go
+++ b/internal/clientman/clientman.go
@@ -15,10 +15,12 @@ import (
 	"github.com/aler9/rtsp-simple-server/internal/stats"
 )
 
+// Parent is implemented by program.
 type Parent interface {
 	Log(string, ...interface{})
 }
 
+// ClientManager is a client.Client manager.
 type ClientManager struct {
 	rtspPort            int
 	readTimeout         time.Duration
@@ -44,6 +46,7 @@ type ClientManager struct {
 	done chan struct{}
 }
 
+// New allocates a ClientManager.
 func New(
 	rtspPort int,
 	readTimeout time.Duration,
@@ -81,11 +84,13 @@ func New(
 	return cm
 }
 
+// Close closes a ClientManager.
 func (cm *ClientManager) Close() {
 	close(cm.terminate)
 	<-cm.done
 }
 
+// Log is the main logging function.
 func (cm *ClientManager) Log(format string, args ...interface{}) {
 	cm.parent.Log(format, args...)
 }
@@ -137,18 +142,22 @@ outer:
 	close(cm.clientClose)
 }
 
+// OnClientClose is called by client.Client.
 func (cm *ClientManager) OnClientClose(c *client.Client) {
 	cm.clientClose <- c
 }
 
+// OnClientDescribe is called by client.Client.
 func (cm *ClientManager) OnClientDescribe(c *client.Client, pathName string, req *base.Request) (client.Path, error) {
 	return cm.pathMan.OnClientDescribe(c, pathName, req)
 }
 
+// OnClientAnnounce is called by client.Client.
 func (cm *ClientManager) OnClientAnnounce(c *client.Client, pathName string, tracks gortsplib.Tracks, req *base.Request) (client.Path, error) {
 	return cm.pathMan.OnClientAnnounce(c, pathName, tracks, req)
 }
 
+// OnClientSetupPlay is called by client.Client.
 func (cm *ClientManager) OnClientSetupPlay(c *client.Client, pathName string, trackId int, req *base.Request) (client.Path, error) {
 	return cm.pathMan.OnClientSetupPlay(c, pathName, trackId, req)
 }
diff --git a/internal/conf/conf.go b/internal/conf/conf.go
index 560f4024..38ef44e2 100644
--- a/internal/conf/conf.go
+++ b/internal/conf/conf.go
@@ -13,6 +13,7 @@ import (
 	"github.com/aler9/rtsp-simple-server/internal/loghandler"
 )
 
+// Conf is the program configuration.
 type Conf struct {
 	Protocols             []string                              `yaml:"protocols"`
 	ProtocolsParsed       map[gortsplib.StreamProtocol]struct{} `yaml:"-" json:"-"`
@@ -143,6 +144,7 @@ func (conf *Conf) fillAndCheck() error {
 	return nil
 }
 
+// Load loads a Conf.
 func Load(fpath string) (*Conf, error) {
 	conf := &Conf{}
 
diff --git a/internal/conf/pathconf.go b/internal/conf/pathconf.go
index 31afd0ea..12eb3e1f 100644
--- a/internal/conf/pathconf.go
+++ b/internal/conf/pathconf.go
@@ -16,6 +16,7 @@ var reUserPass = regexp.MustCompile("^[a-zA-Z0-9!\\$\\(\\)\\*\\+\\.;<=>\\[\\]\\^
 
 const userPassSupportedChars = "A-Z,0-9,!,$,(,),*,+,.,;,<,=,>,[,],^,_,-,{,}"
 
+// PathConf is a path configuration.
 type PathConf struct {
 	Regexp                     *regexp.Regexp           `yaml:"-" json:"-"`
 	Source                     string                   `yaml:"source"`
@@ -224,6 +225,7 @@ func (pconf *PathConf) fillAndCheck(name string) error {
 	return nil
 }
 
+// Equal checks whether two PathConfs are equal.
 func (pconf *PathConf) Equal(other *PathConf) bool {
 	a, _ := json.Marshal(pconf)
 	b, _ := json.Marshal(pconf)
diff --git a/internal/conf/utils.go b/internal/conf/utils.go
index 9e01ecd3..f3953fb9 100644
--- a/internal/conf/utils.go
+++ b/internal/conf/utils.go
@@ -8,6 +8,7 @@ import (
 
 var rePathName = regexp.MustCompile("^[0-9a-zA-Z_\\-/]+$")
 
+// CheckPathName check if a path name is valid.
 func CheckPathName(name string) error {
 	if name == "" {
 		return fmt.Errorf("cannot be empty")
diff --git a/internal/confenv/confenv.go b/internal/confenv/confenv.go
index 91907e9b..b55483d0 100644
--- a/internal/confenv/confenv.go
+++ b/internal/confenv/confenv.go
@@ -125,6 +125,7 @@ func load(env map[string]string, envKey string, rv reflect.Value) error {
 	return fmt.Errorf("unsupported type: %v", rt)
 }
 
+// Load fills a structure with data from the environment.
 func Load(envKey string, v interface{}) error {
 	env := make(map[string]string)
 	for _, kv := range os.Environ() {
diff --git a/internal/confwatcher/confwatcher.go b/internal/confwatcher/confwatcher.go
index f9c2f189..d47ae8e3 100644
--- a/internal/confwatcher/confwatcher.go
+++ b/internal/confwatcher/confwatcher.go
@@ -7,6 +7,7 @@ import (
 	"github.com/fsnotify/fsnotify"
 )
 
+// ConfWatcher is a configuration file watcher.
 type ConfWatcher struct {
 	inner *fsnotify.Watcher
 
@@ -15,6 +16,7 @@ type ConfWatcher struct {
 	done   chan struct{}
 }
 
+// New allocates a ConfWatcher.
 func New(confPath string) (*ConfWatcher, error) {
 	inner, err := fsnotify.NewWatcher()
 	if err != nil {
@@ -39,6 +41,7 @@ func New(confPath string) (*ConfWatcher, error) {
 	return w, nil
 }
 
+// Close closes a ConfWatcher.
 func (w *ConfWatcher) Close() {
 	go func() {
 		for range w.signal {
@@ -69,6 +72,7 @@ outer:
 	close(w.signal)
 }
 
+// Watch returns when the configuration file has changed.
 func (w *ConfWatcher) Watch() chan struct{} {
 	return w.signal
 }
diff --git a/internal/externalcmd/externalcmd.go b/internal/externalcmd/externalcmd.go
index 3fe8ce72..88bd5678 100644
--- a/internal/externalcmd/externalcmd.go
+++ b/internal/externalcmd/externalcmd.go
@@ -12,11 +12,13 @@ const (
 	retryPause = 5 * time.Second
 )
 
+// Environment is a ExternalCmd environment.
 type Environment struct {
 	Path string
 	Port string
 }
 
+// ExternalCmd is an external command.
 type ExternalCmd struct {
 	cmdstr  string
 	restart bool
@@ -29,6 +31,7 @@ type ExternalCmd struct {
 	done chan struct{}
 }
 
+// New allocates an ExternalCmd.
 func New(cmdstr string, restart bool, env Environment) *ExternalCmd {
 	e := &ExternalCmd{
 		cmdstr:    cmdstr,
@@ -42,6 +45,7 @@ func New(cmdstr string, restart bool, env Environment) *ExternalCmd {
 	return e
 }
 
+// Close closes an ExternalCmd.
 func (e *ExternalCmd) Close() {
 	close(e.terminate)
 	<-e.done
diff --git a/internal/loghandler/loghandler.go b/internal/loghandler/loghandler.go
index e756589a..12d54946 100644
--- a/internal/loghandler/loghandler.go
+++ b/internal/loghandler/loghandler.go
@@ -8,11 +8,17 @@ import (
 	"github.com/aler9/rtsp-simple-server/internal/syslog"
 )
 
+// Destination is a log destination.
 type Destination int
 
 const (
+	// DestinationStdout writes logs to the standard output.
 	DestinationStdout Destination = iota
+
+	// DestinationFile writes logs to a file.
 	DestinationFile
+
+	// DestinationSyslog writes logs to the system logger.
 	DestinationSyslog
 )
 
@@ -22,6 +28,7 @@ func (f writeFunc) Write(p []byte) (int, error) {
 	return f(p)
 }
 
+// LogHandler is a log handler.
 type LogHandler struct {
 	destinations map[Destination]struct{}
 
@@ -29,6 +36,7 @@ type LogHandler struct {
 	syslog io.WriteCloser
 }
 
+// New allocates a log handler.
 func New(destinations map[Destination]struct{}, filePath string) (*LogHandler, error) {
 	lh := &LogHandler{
 		destinations: destinations,
@@ -57,6 +65,7 @@ func New(destinations map[Destination]struct{}, filePath string) (*LogHandler, e
 	return lh, nil
 }
 
+// Close closes a log handler.
 func (lh *LogHandler) Close() {
 	if lh.file != nil {
 		lh.file.Close()
diff --git a/internal/metrics/metrics.go b/internal/metrics/metrics.go
index 56d24564..bf010c1f 100644
--- a/internal/metrics/metrics.go
+++ b/internal/metrics/metrics.go
@@ -16,10 +16,12 @@ const (
 	address = ":9998"
 )
 
+// Parent is implemented by program.
 type Parent interface {
 	Log(string, ...interface{})
 }
 
+// Metrics is a metrics exporter.
 type Metrics struct {
 	stats *stats.Stats
 
@@ -28,6 +30,7 @@ type Metrics struct {
 	server   *http.Server
 }
 
+// New allocates a metrics.
 func New(stats *stats.Stats, parent Parent) (*Metrics, error) {
 	listener, err := net.Listen("tcp", address)
 	if err != nil {
@@ -52,6 +55,7 @@ func New(stats *stats.Stats, parent Parent) (*Metrics, error) {
 	return m, nil
 }
 
+// Close closes a Metrics.
 func (m *Metrics) Close() {
 	m.server.Shutdown(context.Background())
 }
diff --git a/internal/path/path.go b/internal/path/path.go
index b2fe4f30..fcdee065 100644
--- a/internal/path/path.go
+++ b/internal/path/path.go
@@ -25,6 +25,7 @@ func newEmptyTimer() *time.Timer {
 	return t
 }
 
+// Parent is implemented by pathman.PathMan.
 type Parent interface {
 	Log(string, ...interface{})
 	OnPathClose(*Path)
@@ -53,11 +54,13 @@ type sourceRedirect struct{}
 
 func (*sourceRedirect) IsSource() {}
 
+// ClientDescribeRes is a client describe response.
 type ClientDescribeRes struct {
 	Path client.Path
 	Err  error
 }
 
+// ClientDescribeReq is a client describe request.
 type ClientDescribeReq struct {
 	Res      chan ClientDescribeRes
 	Client   *client.Client
@@ -65,11 +68,13 @@ type ClientDescribeReq struct {
 	Req      *base.Request
 }
 
+// ClientAnnounceRes is a client announce response.
 type ClientAnnounceRes struct {
 	Path client.Path
 	Err  error
 }
 
+// ClientAnnounceReq is a client announce request.
 type ClientAnnounceReq struct {
 	Res      chan ClientAnnounceRes
 	Client   *client.Client
@@ -78,11 +83,13 @@ type ClientAnnounceReq struct {
 	Req      *base.Request
 }
 
+// ClientSetupPlayRes is a setup/play response.
 type ClientSetupPlayRes struct {
 	Path client.Path
 	Err  error
 }
 
+// ClientSetupPlayReq is a setup/play request.
 type ClientSetupPlayReq struct {
 	Res      chan ClientSetupPlayRes
 	Client   *client.Client
@@ -125,6 +132,7 @@ const (
 	sourceStateReady
 )
 
+// Path is a path.
 type Path struct {
 	rtspPort     int
 	readTimeout  time.Duration
@@ -166,6 +174,7 @@ type Path struct {
 	terminate         chan struct{}
 }
 
+// New allocates a Path.
 func New(
 	rtspPort int,
 	readTimeout time.Duration,
@@ -209,10 +218,12 @@ func New(
 	return pa
 }
 
+// Close closes a path.
 func (pa *Path) Close() {
 	close(pa.terminate)
 }
 
+// Log is the main logging function.
 func (pa *Path) Log(format string, args ...interface{}) {
 	pa.parent.Log("[path "+pa.name+"] "+format, args...)
 }
@@ -747,62 +758,75 @@ func (pa *Path) scheduleClose() {
 	pa.closeTimerStarted = true
 }
 
+// ConfName returns the configuration name of this path.
+func (pa *Path) ConfName() string {
+	return pa.confName
+}
+
+// Conf returns the configuration of this path.
+func (pa *Path) Conf() *conf.PathConf {
+	return pa.conf
+}
+
+// Name returns the name of this path.
+func (pa *Path) Name() string {
+	return pa.name
+}
+
+// SourceTrackCount returns the number of tracks of the source this path.
+func (pa *Path) SourceTrackCount() int {
+	return pa.sourceTrackCount
+}
+
+// OnSourceSetReady is called by a source.
 func (pa *Path) OnSourceSetReady(tracks gortsplib.Tracks) {
 	pa.sourceSdp = tracks.Write()
 	pa.sourceTrackCount = len(tracks)
 	pa.sourceSetReady <- struct{}{}
 }
 
+// OnSourceSetNotReady is called by a source.
 func (pa *Path) OnSourceSetNotReady() {
 	pa.sourceSetNotReady <- struct{}{}
 }
 
-func (pa *Path) ConfName() string {
-	return pa.confName
-}
-
-func (pa *Path) Conf() *conf.PathConf {
-	return pa.conf
-}
-
-func (pa *Path) Name() string {
-	return pa.name
-}
-
-func (pa *Path) SourceTrackCount() int {
-	return pa.sourceTrackCount
-}
-
+// OnPathManDescribe is called by pathman.PathMan.
 func (pa *Path) OnPathManDescribe(req ClientDescribeReq) {
 	pa.clientDescribe <- req
 }
 
+// OnPathManSetupPlay is called by pathman.PathMan.
 func (pa *Path) OnPathManSetupPlay(req ClientSetupPlayReq) {
 	pa.clientSetupPlay <- req
 }
 
+// OnPathManAnnounce is called by pathman.PathMan.
 func (pa *Path) OnPathManAnnounce(req ClientAnnounceReq) {
 	pa.clientAnnounce <- req
 }
 
+// OnClientRemove is called by client.Client.
 func (pa *Path) OnClientRemove(c *client.Client) {
 	res := make(chan struct{})
 	pa.clientRemove <- clientRemoveReq{res, c}
 	<-res
 }
 
+// OnClientPlay is called by client.Client.
 func (pa *Path) OnClientPlay(c *client.Client) {
 	res := make(chan struct{})
 	pa.clientPlay <- clientPlayReq{res, c}
 	<-res
 }
 
+// OnClientRecord is called by client.Client.
 func (pa *Path) OnClientRecord(c *client.Client) {
 	res := make(chan struct{})
 	pa.clientRecord <- clientRecordReq{res, c}
 	<-res
 }
 
+// OnFrame is called by a source or by a client.Client.
 func (pa *Path) OnFrame(trackId int, streamType gortsplib.StreamType, buf []byte) {
 	pa.readers.forwardFrame(trackId, streamType, buf)
 }
diff --git a/internal/path/readersmap.go b/internal/path/readersmap.go
index acdf5767..0ae7d9a2 100644
--- a/internal/path/readersmap.go
+++ b/internal/path/readersmap.go
@@ -7,29 +7,29 @@ import (
 	"github.com/aler9/gortsplib/base"
 )
 
-type Reader interface {
+type reader interface {
 	OnReaderFrame(int, base.StreamType, []byte)
 }
 
 type readersMap struct {
 	mutex sync.RWMutex
-	ma    map[Reader]struct{}
+	ma    map[reader]struct{}
 }
 
 func newReadersMap() *readersMap {
 	return &readersMap{
-		ma: make(map[Reader]struct{}),
+		ma: make(map[reader]struct{}),
 	}
 }
 
-func (m *readersMap) add(reader Reader) {
+func (m *readersMap) add(reader reader) {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
 	m.ma[reader] = struct{}{}
 }
 
-func (m *readersMap) remove(reader Reader) {
+func (m *readersMap) remove(reader reader) {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
diff --git a/internal/pathman/pathman.go b/internal/pathman/pathman.go
index 4371f312..25e6b223 100644
--- a/internal/pathman/pathman.go
+++ b/internal/pathman/pathman.go
@@ -15,10 +15,12 @@ import (
 	"github.com/aler9/rtsp-simple-server/internal/stats"
 )
 
+// Parent is implemented by program.
 type Parent interface {
 	Log(string, ...interface{})
 }
 
+// PathManager is a path.Path manager.
 type PathManager struct {
 	rtspPort     int
 	readTimeout  time.Duration
@@ -44,6 +46,7 @@ type PathManager struct {
 	done        chan struct{}
 }
 
+// New allocates a PathManager.
 func New(
 	rtspPort int,
 	readTimeout time.Duration,
@@ -78,6 +81,7 @@ func New(
 	return pm
 }
 
+// Close closes a PathManager.
 func (pm *PathManager) Close() {
 	go func() {
 		for range pm.clientClose {
@@ -87,6 +91,7 @@ func (pm *PathManager) Close() {
 	<-pm.done
 }
 
+// Log is the main logging function.
 func (pm *PathManager) Log(format string, args ...interface{}) {
 	pm.parent.Log(format, args...)
 }
@@ -283,18 +288,22 @@ func (pm *PathManager) findPathConf(name string) (string, *conf.PathConf, error)
 	return "", nil, fmt.Errorf("unable to find a valid configuration for path '%s'", name)
 }
 
+// OnProgramConfReload is called by program.
 func (pm *PathManager) OnProgramConfReload(pathConfs map[string]*conf.PathConf) {
 	pm.confReload <- pathConfs
 }
 
+// OnPathClose is called by path.Path.
 func (pm *PathManager) OnPathClose(pa *path.Path) {
 	pm.pathClose <- pa
 }
 
+// OnPathClientClose is called by path.Path.
 func (pm *PathManager) OnPathClientClose(c *client.Client) {
 	pm.clientClose <- c
 }
 
+// OnClientDescribe is called by client.Client.
 func (pm *PathManager) OnClientDescribe(c *client.Client, pathName string, req *base.Request) (client.Path, error) {
 	res := make(chan path.ClientDescribeRes)
 	pm.clientDescribe <- path.ClientDescribeReq{res, c, pathName, req}
@@ -302,6 +311,7 @@ func (pm *PathManager) OnClientDescribe(c *client.Client, pathName string, req *
 	return re.Path, re.Err
 }
 
+// OnClientAnnounce is called by client.Client.
 func (pm *PathManager) OnClientAnnounce(c *client.Client, pathName string, tracks gortsplib.Tracks, req *base.Request) (client.Path, error) {
 	res := make(chan path.ClientAnnounceRes)
 	pm.clientAnnounce <- path.ClientAnnounceReq{res, c, pathName, tracks, req}
@@ -309,6 +319,7 @@ func (pm *PathManager) OnClientAnnounce(c *client.Client, pathName string, track
 	return re.Path, re.Err
 }
 
+// OnClientSetupPlay is called by client.Client.
 func (pm *PathManager) OnClientSetupPlay(c *client.Client, pathName string, trackId int, req *base.Request) (client.Path, error) {
 	res := make(chan path.ClientSetupPlayRes)
 	pm.clientSetupPlay <- path.ClientSetupPlayReq{res, c, pathName, trackId, req}
@@ -316,6 +327,7 @@ func (pm *PathManager) OnClientSetupPlay(c *client.Client, pathName string, trac
 	return re.Path, re.Err
 }
 
+// ClientClose is called by client.Client.
 func (pm *PathManager) ClientClose() chan *client.Client {
 	return pm.clientClose
 }
diff --git a/internal/pprof/pprof.go b/internal/pprof/pprof.go
index 8275e304..ecb87f10 100644
--- a/internal/pprof/pprof.go
+++ b/internal/pprof/pprof.go
@@ -4,6 +4,8 @@ import (
 	"context"
 	"net"
 	"net/http"
+
+	// start pprof
 	_ "net/http/pprof"
 )
 
@@ -11,15 +13,18 @@ const (
 	address = ":9999"
 )
 
+// Parent is implemented by program.
 type Parent interface {
 	Log(string, ...interface{})
 }
 
+// Pprof is a performance metrics exporter.
 type Pprof struct {
 	listener net.Listener
 	server   *http.Server
 }
 
+// New allocates a Pprof.
 func New(parent Parent) (*Pprof, error) {
 	listener, err := net.Listen("tcp", address)
 	if err != nil {
@@ -40,6 +45,7 @@ func New(parent Parent) (*Pprof, error) {
 	return pp, nil
 }
 
+// Close closes a Pprof.
 func (pp *Pprof) Close() {
 	pp.server.Shutdown(context.Background())
 }
diff --git a/internal/servertcp/server.go b/internal/servertcp/server.go
index 0e9c366f..6926cb80 100644
--- a/internal/servertcp/server.go
+++ b/internal/servertcp/server.go
@@ -4,10 +4,12 @@ import (
 	"net"
 )
 
+// Parent is implemented by program.
 type Parent interface {
 	Log(string, ...interface{})
 }
 
+// Server is a RTSP TCP server.
 type Server struct {
 	parent Parent
 
@@ -18,6 +20,7 @@ type Server struct {
 	done   chan struct{}
 }
 
+// New allocates a Server.
 func New(port int, parent Parent) (*Server, error) {
 	listener, err := net.ListenTCP("tcp", &net.TCPAddr{
 		Port: port,
@@ -39,6 +42,7 @@ func New(port int, parent Parent) (*Server, error) {
 	return s, nil
 }
 
+// Close closes a Server.
 func (s *Server) Close() {
 	go func() {
 		for co := range s.accept {
@@ -64,6 +68,7 @@ func (s *Server) run() {
 	close(s.accept)
 }
 
+// Accept returns a channel to accept incoming connections.
 func (s *Server) Accept() <-chan net.Conn {
 	return s.accept
 }
diff --git a/internal/serverudp/server.go b/internal/serverudp/server.go
index bc6bf0f7..702fd73e 100644
--- a/internal/serverudp/server.go
+++ b/internal/serverudp/server.go
@@ -14,6 +14,7 @@ const (
 	readBufferSize = 2048
 )
 
+// Publisher is implemented by client.Client.
 type Publisher interface {
 	OnUdpPublisherFrame(int, base.StreamType, []byte)
 }
@@ -28,6 +29,7 @@ type bufAddrPair struct {
 	addr *net.UDPAddr
 }
 
+// Parent is implemented by program.
 type Parent interface {
 	Log(string, ...interface{})
 }
@@ -48,6 +50,7 @@ func (p *publisherAddr) fill(ip net.IP, port int) {
 	}
 }
 
+// Server is a RTSP UDP server.
 type Server struct {
 	writeTimeout time.Duration
 	streamType   gortsplib.StreamType
@@ -64,6 +67,7 @@ type Server struct {
 	done chan struct{}
 }
 
+// New allocates a Server.
 func New(writeTimeout time.Duration,
 	port int,
 	streamType gortsplib.StreamType,
@@ -98,6 +102,7 @@ func New(writeTimeout time.Duration,
 	return s, nil
 }
 
+// Close closes a Server.
 func (s *Server) Close() {
 	s.pc.Close()
 	<-s.done
@@ -142,14 +147,17 @@ func (s *Server) run() {
 	<-writeDone
 }
 
+// Port returns the server local port.
 func (s *Server) Port() int {
 	return s.pc.LocalAddr().(*net.UDPAddr).Port
 }
 
+// Write writes a UDP packet.
 func (s *Server) Write(data []byte, addr *net.UDPAddr) {
 	s.write <- bufAddrPair{data, addr}
 }
 
+// AddPublisher adds a publisher.
 func (s *Server) AddPublisher(ip net.IP, port int, publisher Publisher, trackId int) {
 	s.publishersMutex.Lock()
 	defer s.publishersMutex.Unlock()
@@ -163,6 +171,7 @@ func (s *Server) AddPublisher(ip net.IP, port int, publisher Publisher, trackId
 	}
 }
 
+// RemovePublisher removes a publisher.
 func (s *Server) RemovePublisher(ip net.IP, port int, publisher Publisher) {
 	s.publishersMutex.Lock()
 	defer s.publishersMutex.Unlock()
diff --git a/internal/sourcertmp/source.go b/internal/sourcertmp/source.go
index a085d9a9..b5aee9b9 100644
--- a/internal/sourcertmp/source.go
+++ b/internal/sourcertmp/source.go
@@ -21,6 +21,7 @@ const (
 	retryPause = 5 * time.Second
 )
 
+// Parent is implemeneted by path.Path.
 type Parent interface {
 	Log(string, ...interface{})
 	OnSourceSetReady(gortsplib.Tracks)
@@ -28,6 +29,7 @@ type Parent interface {
 	OnFrame(int, gortsplib.StreamType, []byte)
 }
 
+// Source is a RTMP source.
 type Source struct {
 	ur     string
 	state  bool
@@ -39,6 +41,7 @@ type Source struct {
 	terminate chan struct{}
 }
 
+// New allocates a Source.
 func New(ur string,
 	wg *sync.WaitGroup,
 	stats *stats.Stats,
@@ -59,14 +62,17 @@ func New(ur string,
 	return s
 }
 
+// Close closes a Source.
 func (s *Source) Close() {
 	atomic.AddInt64(s.stats.CountSourcesRtmpRunning, -1)
 	s.parent.Log("rtmp source stopped")
 	close(s.terminate)
 }
 
+// IsSource implements path.source.
 func (s *Source) IsSource() {}
 
+// IsSourceExternal implements path.sourceExternal.
 func (s *Source) IsSourceExternal() {}
 
 func (s *Source) run() {
diff --git a/internal/sourcertsp/source.go b/internal/sourcertsp/source.go
index a427e1e6..b4c3ce5b 100644
--- a/internal/sourcertsp/source.go
+++ b/internal/sourcertsp/source.go
@@ -14,6 +14,7 @@ const (
 	retryPause = 5 * time.Second
 )
 
+// Parent is implemented by path.Path.
 type Parent interface {
 	Log(string, ...interface{})
 	OnSourceSetReady(gortsplib.Tracks)
@@ -21,6 +22,7 @@ type Parent interface {
 	OnFrame(int, gortsplib.StreamType, []byte)
 }
 
+// Source is a RTSP source.
 type Source struct {
 	ur           string
 	proto        gortsplib.StreamProtocol
@@ -37,6 +39,7 @@ type Source struct {
 	done chan struct{}
 }
 
+// New allocates a Source.
 func New(ur string,
 	proto gortsplib.StreamProtocol,
 	readTimeout time.Duration,
@@ -63,14 +66,17 @@ func New(ur string,
 	return s
 }
 
+// Close closes a Source.
 func (s *Source) Close() {
 	atomic.AddInt64(s.stats.CountSourcesRtsp, -1)
 	s.parent.Log("rtsp source stopped")
 	close(s.terminate)
 }
 
+// IsSource implements path.source.
 func (s *Source) IsSource() {}
 
+// IsSourceExternal implements path.sourceExternal.
 func (s *Source) IsSourceExternal() {}
 
 func (s *Source) run() {
diff --git a/internal/stats/stats.go b/internal/stats/stats.go
index 24422e5c..6491ae0c 100644
--- a/internal/stats/stats.go
+++ b/internal/stats/stats.go
@@ -5,6 +5,7 @@ func ptrInt64() *int64 {
 	return &v
 }
 
+// Stats contains statistics.
 type Stats struct {
 	// use pointers to avoid a crash on 32bit platforms
 	// https://github.com/golang/go/issues/9959
@@ -17,6 +18,7 @@ type Stats struct {
 	CountSourcesRtmpRunning *int64
 }
 
+// New allocates a Stats.
 func New() *Stats {
 	return &Stats{
 		CountClients:            ptrInt64(),
diff --git a/internal/syslog/syslog_unix.go b/internal/syslog/syslog_unix.go
index 87f1184c..1c5c8440 100644
--- a/internal/syslog/syslog_unix.go
+++ b/internal/syslog/syslog_unix.go
@@ -11,6 +11,7 @@ type syslog struct {
 	inner *native.Writer
 }
 
+// New allocates a io.WriteCloser that writes to the system log.
 func New(prefix string) (io.WriteCloser, error) {
 	inner, err := native.New(native.LOG_INFO|native.LOG_DAEMON, prefix)
 	if err != nil {
@@ -22,10 +23,12 @@ func New(prefix string) (io.WriteCloser, error) {
 	}, nil
 }
 
+// Close implements io.WriteCloser.
 func (ls *syslog) Close() error {
 	return ls.inner.Close()
 }
 
+// Write implements io.WriteCloser.
 func (ls *syslog) Write(p []byte) (int, error) {
 	return ls.inner.Write(p)
 }
diff --git a/internal/syslog/syslog_win.go b/internal/syslog/syslog_win.go
index 0e2929d1..7f23156b 100644
--- a/internal/syslog/syslog_win.go
+++ b/internal/syslog/syslog_win.go
@@ -10,14 +10,17 @@ import (
 type syslog struct {
 }
 
+// New allocates a io.WriteCloser that writes to the system log.
 func New(prefix string) (io.WriteCloser, error) {
 	return nil, fmt.Errorf("not implemented on windows")
 }
 
+// Close implements io.WriteCloser.
 func (ls *syslog) Close() error {
 	return nil
 }
 
+// Write implements io.WriteCloser.
 func (ls *syslog) Write(p []byte) (int, error) {
 	return 0, nil
 }
diff --git a/main.go b/main.go
index 1f5b9108..da4ecefc 100644
--- a/main.go
+++ b/main.go
@@ -22,6 +22,7 @@ import (
 	"github.com/aler9/rtsp-simple-server/internal/stats"
 )
 
+// Version can be overridden by build flags.
 var Version = "v0.0.0"
 
 type program struct {