52 lines
835 B
Go
52 lines
835 B
Go
package main
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import (
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"log"
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"net"
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"sync"
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)
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type udpListener struct {
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nconn *net.UDPConn
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logPrefix string
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cb func([]byte)
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}
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func newUdpListener(port int, logPrefix string, cb func([]byte)) (*udpListener, error) {
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nconn, err := net.ListenUDP("udp", &net.UDPAddr{
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Port: port,
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})
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if err != nil {
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return nil, err
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}
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l := &udpListener{
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nconn: nconn,
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logPrefix: logPrefix,
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cb: cb,
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}
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l.log("opened on :%d", port)
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return l, nil
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}
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func (l *udpListener) log(format string, args ...interface{}) {
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log.Printf("["+l.logPrefix+" listener] "+format, args...)
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}
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func (l *udpListener) run(wg sync.WaitGroup) {
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defer wg.Done()
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buf := make([]byte, 2048) // UDP MTU is 1400
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for {
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n, _, err := l.nconn.ReadFromUDP(buf)
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if err != nil {
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l.log("ERR: %s", err)
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break
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}
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l.cb(buf[:n])
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}
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}
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