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path: root/pkg/server/queue/queue.go
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package queue

import (
	"io"
)

type Q chan []byte

type reader struct {
	b []byte
	q Q
}

type writer struct {
	q Q
}

func New() Q {
	return make(Q)
}

func (q Q) Reader() io.Reader {
	return &reader{q: q}
}

func (r *reader) Read(p []byte) (int, error) {
	if len(r.b) == 0 {
		r.b = <-r.q
		if r.b == nil {
			return 0, io.EOF
		}
	}

	n := copy(p, r.b)
	r.b = r.b[n:]

	return n, nil
}

func (q Q) Writer() io.Writer {
	return &writer{q: q}
}

func (w *writer) Write(p []byte) (int, error) {
	buf := make([]byte, len(p))
	copy(buf, p)
	w.q <- buf

	return len(p), nil
}

func IoCopy(r io.Reader, w io.Writer) error {
	if _, err := io.Copy(w, r); err != nil {
		if err != io.EOF {
			return err
		}
	}

	return nil
}