copy.go

package main

import (
	"bufio"
	"io"
)

func Copy(dest *bufio.ReadWriter, src *bufio.ReadWriter) {
	buf := make([]byte, 40*1024)
	for {
		n, err := src.Read(buf)
		if err != nil && err != io.EOF {
			log.Printf("Read failed: %v", err)
			return
		}
		if n == 0 {
			return
		}
		dest.Write(buf[0:n])
		dest.Flush()
	}
}

func CopyBidir(conn1 io.ReadWriteCloser, rw1 *bufio.ReadWriter, conn2 io.ReadWriteCloser, rw2 *bufio.ReadWriter) {
	finished := make(chan bool)

	go func() {
		Copy(rw2, rw1)
		conn2.Close()
		finished <- true
	}()
	go func() {
		Copy(rw1, rw2)
		conn1.Close()
		finished <- true
	}()

	<-finished
	<-finished
}