a simple golang echo server.

echo.go

package main

import (
	"bufio"
	"fmt"
	"log"
	"net"
)

func handleConnection(conn net.Conn) {
	defer conn.Close()

	reader := bufio.NewReaderSize(conn, 2048)
	tmpChan := make(chan []byte, 20140)

	if tcp, ok := conn.(*net.TCPConn); ok {
		tcp.SetNoDelay(true)
	}

	go func() {
		for {
			data := <-tmpChan
			remain := len(tmpChan)

			for i := 0; i < remain; i++ {
				left := <-tmpChan
				data = append(data, left...)
			}

			size, err1 := conn.Write(data)
			if err1 != nil || size != len(data) {
				fmt.Println("write error: ", err1, size)
				return
			}
		}

	}()

	buf := make([]byte, 8192)
	for {
		n, err := reader.Read(buf)
		if err != nil {
			fmt.Println("read error: ", err)
			return
		}

		for pos := 0; pos < n; pos += 64 {
			end := pos + 64
			if end > n {
				end = n
			}
			send := []byte{}
			send = append(send, buf[pos:end]...)
			tmpChan <- send
		}
	}
}

func main() {
	ln, err := net.Listen("tcp", ":3050")
	if err != nil {
		panic(err)
	}

	fmt.Println("listen 3050 ok")

	for {
		conn, err := ln.Accept()
		if err != nil {
			log.Fatal("get client connection error: ", err)
		}

		go handleConnection(conn)
	}
}