wal-g

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package splitmerge
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import (
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	"io"
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)
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type writeResult struct {
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	n   int
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	err error
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}
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// channelWriter provider io.WriteCloser interface on top of `ch` chan []byte
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// i.e. it sends all data written by Write(data) to `ch` channel and waits for response: bytes written & errors
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type channelWriter struct {
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	ch       chan<- []byte
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	resultCh <-chan writeResult
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}
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var _ io.WriteCloser = &channelWriter{}
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func newChannelWriter(ch chan<- []byte, resultCh <-chan writeResult) io.WriteCloser {
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	return &channelWriter{
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		ch:       ch,
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		resultCh: resultCh,
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	}
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}
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func (cw *channelWriter) Write(data []byte) (int, error) {
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	cw.ch <- data
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	wr, ok := <-cw.resultCh
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	if !ok {
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		return 0, io.ErrShortWrite
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	}
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	return wr.n, wr.err
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}
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func (cw *channelWriter) Close() error {
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	close(cw.ch)
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	return nil
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}
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