49 lines
848 B
Go
49 lines
848 B
Go
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package dht
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import (
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"context"
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"errors"
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"fmt"
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"time"
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"github.com/anacrolix/dht/v2/krpc"
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)
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var TransactionTimeout = errors.New("transaction timed out")
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// Transaction keeps track of a message exchange between nodes, such as a
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// query message and a response message.
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type Transaction struct {
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onResponse func(krpc.Msg)
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}
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func (t *Transaction) handleResponse(m krpc.Msg) {
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t.onResponse(m)
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}
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const defaultMaxQuerySends = 1
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func transactionSender(
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ctx context.Context,
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send func() error,
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resendDelay func() time.Duration,
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maxSends int,
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) error {
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var delay time.Duration
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sends := 0
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for sends < maxSends {
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select {
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case <-time.After(delay):
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err := send()
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sends++
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if err != nil {
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return fmt.Errorf("send %d: %w", sends, err)
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}
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delay = resendDelay()
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case <-ctx.Done():
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return ctx.Err()
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}
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}
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return nil
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}
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