1package terminal
2
3import (
4	"fmt"
5	"io"
6)
7
8type FileDescriptorProxy struct {
9	StopCh chan error
10}
11
12// stoppers is the number of goroutines that may attempt to call Stop()
13func NewFileDescriptorProxy(stoppers int) *FileDescriptorProxy {
14	return &FileDescriptorProxy{
15		StopCh: make(chan error, stoppers+2), // each proxy() call is a stopper
16	}
17}
18
19func (p *FileDescriptorProxy) GetStopCh() chan error {
20	return p.StopCh
21}
22
23func (p *FileDescriptorProxy) Serve(upstream, downstream io.ReadWriter, upstreamAddr, downstreamAddr string) error {
24	// This signals the upstream terminal to kill the exec'd process
25	defer upstream.Write(eot)
26
27	go p.proxy(upstream, downstream, upstreamAddr, downstreamAddr)
28	go p.proxy(downstream, upstream, downstreamAddr, upstreamAddr)
29
30	err := <-p.StopCh
31	return err
32}
33
34func (p *FileDescriptorProxy) proxy(to, from io.ReadWriter, toAddr, fromAddr string) {
35	_, err := io.Copy(to, from)
36	if err != nil {
37		p.StopCh <- fmt.Errorf("copying from %s to %s: %s", fromAddr, toAddr, err)
38	}
39}
40