Matt Joiner
72 lines
1.3 KiB
Go
72 lines
1.3 KiB
Go
package utp
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import (
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"log"
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"time"
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"github.com/anacrolix/missinggo"
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)
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type send struct {
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acked bool // Closed with Conn lock.
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payloadSize uint32
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started missinggo.MonotonicTime
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_type st
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connID uint16
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payload []byte
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seqNr uint16
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conn *Conn
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acksSkipped int
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resendTimer *time.Timer
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numResends int
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}
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// first is true if this is the first time the send is acked. latency is
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// calculated for the first ack.
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func (s *send) Ack() (latency time.Duration, first bool) {
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first = !s.acked
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if first {
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latency = missinggo.MonotonicSince(s.started)
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}
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s.acked = true
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cond.Broadcast()
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if s.resendTimer != nil {
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s.resendTimer.Stop()
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s.resendTimer = nil
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}
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return
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}
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func (s *send) timedOut() {
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s.conn.destroy(errAckTimeout)
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}
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func (s *send) timeoutResend() {
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mu.Lock()
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defer mu.Unlock()
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if missinggo.MonotonicSince(s.started) >= writeTimeout {
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s.timedOut()
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return
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}
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if s.acked || s.conn.destroyed.Get() {
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return
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}
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rt := s.conn.resendTimeout()
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go s.resend()
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s.numResends++
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s.resendTimer.Reset(rt * time.Duration(s.numResends))
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}
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func (s *send) resend() {
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mu.Lock()
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defer mu.Unlock()
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if s.acked {
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return
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}
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err := s.conn.send(s._type, s.connID, s.payload, s.seqNr)
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if err != nil {
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log.Printf("error resending packet: %s", err)
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}
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}
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