Files
go2rtc/pkg/doorbird/backchannel.go
T
2025-07-31 21:07:45 +02:00

425 lines
7.9 KiB
Go

package doorbird
import (
"bufio"
"errors"
"fmt"
"net"
"net/http"
"net/url"
"sync"
"time"
"github.com/AlexxIT/go2rtc/pkg/core"
"github.com/AlexxIT/go2rtc/pkg/pcm"
"github.com/pion/rtp"
)
const (
AudioMixerInterval = 10 * time.Millisecond
AudioChannelBuffer = 10
OutputChannelBuffer = 10
SenderCleanupInterval = 5 * time.Second
SenderTimeoutDuration = 5 * time.Second
)
var (
cltMu sync.Mutex
cltMap = make(map[string]*Client)
)
type AudioMixer struct {
mu sync.Mutex
streams map[string]chan []byte
output chan []byte
running bool
closed bool
}
func NewAudioMixer() *AudioMixer {
return &AudioMixer{
streams: make(map[string]chan []byte),
output: make(chan []byte, OutputChannelBuffer),
}
}
func (m *AudioMixer) AddStream(id string) chan []byte {
m.mu.Lock()
defer m.mu.Unlock()
if m.closed {
ch := make(chan []byte)
close(ch)
return ch
}
if !m.running {
m.running = true
go m.mixLoop()
}
stream := make(chan []byte, AudioChannelBuffer)
m.streams[id] = stream
return stream
}
func (m *AudioMixer) RemoveStream(id string) {
m.mu.Lock()
defer m.mu.Unlock()
if stream, exists := m.streams[id]; exists {
close(stream)
delete(m.streams, id)
}
}
func (m *AudioMixer) mixLoop() {
ticker := time.NewTicker(AudioMixerInterval)
defer ticker.Stop()
for range ticker.C {
m.mu.Lock()
if m.closed {
m.mu.Unlock()
return
}
if len(m.streams) == 0 {
m.mu.Unlock()
continue
}
var pcmSamples [][]int16
activeStreams := 0
for _, stream := range m.streams {
select {
case data := <-stream:
if len(data) > 0 {
samples := make([]int16, len(data))
for i, sample := range data {
samples[i] = pcm.PCMUtoPCM(sample)
}
pcmSamples = append(pcmSamples, samples)
activeStreams++
}
default:
}
}
m.mu.Unlock()
if activeStreams == 0 {
continue
}
var mixedLength int
for _, samples := range pcmSamples {
if len(samples) > mixedLength {
mixedLength = len(samples)
}
}
if mixedLength == 0 {
continue
}
mixed := make([]int16, mixedLength)
for i := 0; i < mixedLength; i++ {
var sum int32
var count int32
for _, samples := range pcmSamples {
if i < len(samples) {
sum += int32(samples[i])
count++
}
}
if count > 0 {
averaged := sum / count
if averaged > 32767 {
mixed[i] = 32767
} else if averaged < -32768 {
mixed[i] = -32768
} else {
mixed[i] = int16(averaged)
}
}
}
output := make([]byte, len(mixed))
for i, sample := range mixed {
output[i] = pcm.PCMtoPCMU(sample)
}
select {
case m.output <- output:
default:
}
}
}
type Client struct {
core.Connection
conn net.Conn
mixer *AudioMixer
trackMap map[*core.Sender]string
senderStats map[*core.Sender]time.Time
mu sync.RWMutex
}
func Dial(rawURL string) (*Client, error) {
cltMu.Lock()
defer cltMu.Unlock()
if existingClient, exists := cltMap[rawURL]; exists && existingClient.conn != nil {
return existingClient, nil
}
u, err := url.Parse(rawURL)
if err != nil {
return nil, err
}
user := u.User.Username()
pass, _ := u.User.Password()
if u.Port() == "" {
u.Host += ":80"
}
conn, err := net.DialTimeout("tcp", u.Host, core.ConnDialTimeout)
if err != nil {
return nil, err
}
s := fmt.Sprintf("POST /bha-api/audio-transmit.cgi?http-user=%s&http-password=%s HTTP/1.0\r\n", user, pass) +
"Content-Type: audio/basic\r\n" +
"Content-Length: 9999999\r\n" +
"Connection: Keep-Alive\r\n" +
"Cache-Control: no-cache\r\n" +
"\r\n"
_ = conn.SetWriteDeadline(time.Now().Add(core.ConnDeadline))
if _, err = conn.Write([]byte(s)); err != nil {
conn.Close()
return nil, err
}
resp, _ := http.ReadResponse(bufio.NewReader(conn), nil)
if resp != nil {
switch resp.StatusCode {
case 204:
conn.Close()
return nil, errors.New("DoorBird user has no api permission")
case 503:
conn.Close()
return nil, errors.New("DoorBird device is busy")
}
}
medias := []*core.Media{
{
Kind: core.KindAudio,
Direction: core.DirectionSendonly,
Codecs: []*core.Codec{
{Name: core.CodecPCMU, ClockRate: 8000},
},
},
}
client := &Client{
Connection: core.Connection{
ID: core.NewID(),
FormatName: "doorbird",
Protocol: "http",
URL: rawURL,
Medias: medias,
},
conn: conn,
mixer: NewAudioMixer(),
trackMap: make(map[*core.Sender]string),
senderStats: make(map[*core.Sender]time.Time),
}
cltMap[rawURL] = client
return client, nil
}
func (c *Client) GetTrack(media *core.Media, codec *core.Codec) (*core.Receiver, error) {
return nil, core.ErrCantGetTrack
}
func (c *Client) AddTrack(media *core.Media, codec *core.Codec, track *core.Receiver) error {
c.mu.Lock()
defer c.mu.Unlock()
sender := core.NewSender(media, track.Codec)
trackID := fmt.Sprintf("%d", core.NewID())
streamChan := c.mixer.AddStream(trackID)
sender.Handler = func(pkt *rtp.Packet) {
if len(pkt.Payload) == 0 {
return
}
c.mu.RLock()
conn := c.conn
c.mu.RUnlock()
if conn != nil {
select {
case streamChan <- pkt.Payload:
c.mu.Lock()
c.senderStats[sender] = time.Now()
c.mu.Unlock()
default:
}
}
}
c.trackMap[sender] = trackID
c.senderStats[sender] = time.Now()
if len(c.Senders) == 0 {
go func() {
defer func() {
if r := recover(); r != nil {
}
}()
for mixedData := range c.mixer.output {
c.mu.RLock()
conn := c.conn
c.mu.RUnlock()
if conn != nil && len(mixedData) > 0 {
_ = conn.SetWriteDeadline(time.Now().Add(core.ConnDeadline))
if n, err := conn.Write(mixedData); err == nil {
c.Send += n
} else {
break
}
}
}
}()
}
sender.WithParent(track).Start()
c.Senders = append(c.Senders, sender)
return nil
}
func (c *Client) Start() error {
if c.conn == nil {
return nil
}
go func() {
ticker := time.NewTicker(SenderCleanupInterval)
defer ticker.Stop()
for range ticker.C {
c.cleanupOrphanedSenders()
}
}()
buf := make([]byte, 1)
for {
_ = c.conn.SetReadDeadline(time.Now().Add(30 * time.Second))
_, err := c.conn.Read(buf)
if err != nil {
c.cleanup()
cltMu.Lock()
delete(cltMap, c.URL)
cltMu.Unlock()
return err
}
}
}
func (c *Client) cleanup() {
c.mu.Lock()
defer c.mu.Unlock()
if c.conn != nil {
c.conn.Close()
c.conn = nil
}
if c.mixer != nil {
c.mixer.mu.Lock()
c.mixer.closed = true
for id, stream := range c.mixer.streams {
close(stream)
delete(c.mixer.streams, id)
}
if c.mixer.running {
close(c.mixer.output)
c.mixer.running = false
}
c.mixer.mu.Unlock()
}
for _, sender := range c.Senders {
sender.Close()
}
c.Senders = nil
c.trackMap = make(map[*core.Sender]string)
c.senderStats = make(map[*core.Sender]time.Time)
cltMu.Lock()
delete(cltMap, c.URL)
cltMu.Unlock()
}
func (c *Client) cleanupOrphanedSenders() {
c.mu.Lock()
defer c.mu.Unlock()
now := time.Now()
removedCount := 0
validIndex := 0
for i, sender := range c.Senders {
lastActivity, exists := c.senderStats[sender]
if sender.State() == "closed" || !exists || now.Sub(lastActivity) >= SenderTimeoutDuration {
if trackID, exists := c.trackMap[sender]; exists {
c.mixer.RemoveStream(trackID)
delete(c.trackMap, sender)
}
delete(c.senderStats, sender)
sender.Close()
removedCount++
} else {
c.Senders[validIndex] = c.Senders[i]
validIndex++
}
}
c.Senders = c.Senders[:validIndex]
if removedCount > 0 {
fmt.Printf("DoorBird: Cleaned up %d orphaned senders, %d remain active\n", removedCount, validIndex)
}
}
func (c *Client) RemoveTrack(sender *core.Sender) {
c.mu.Lock()
defer c.mu.Unlock()
if trackID, exists := c.trackMap[sender]; exists {
c.mixer.RemoveStream(trackID)
delete(c.trackMap, sender)
}
delete(c.senderStats, sender)
for i, s := range c.Senders {
if s == sender {
c.Senders = append(c.Senders[:i], c.Senders[i+1:]...)
break
}
}
}