Merge pull request 'smoketest' (#1) from smoketest into master

Reviewed-on: https://git.fputs.com/fputs/protohackers/pulls/1

cmd/smoketest/main.go

@@ -2,41 +2,39 @@ package main
 
 import (
 	"fmt"
+	"io"
+	"log"
 	"net"
 	"os"
 )
 
 const (
-	connHost = "localhost"
 	connPort = "3030"
-	connType = "tcp"
+	connType = "tcp4"
 )
 
 func main() {
-	l, err := net.Listen(connType, connHost+":"+connPort)
+	l, err := net.Listen(connType, ":"+connPort)
 	if err != nil {
-		fmt.Printf("net.Listen fail: %v\n", err)
+		log.Fatalln(err)
 		os.Exit(1)
 	}
 	defer l.Close()
 
-	fmt.Println(fmt.Sprintf("Listening on %s:%s", connHost, connPort))
+	fmt.Println(fmt.Sprintf("Listening on port %s", connPort))
 
 	for {
 		conn, err := l.Accept()
 		if err != nil {
-			fmt.Printf("Error accepting: %v\n", err)
+			log.Fatalln(err)
 		}
 		go handleRequest(conn)
 	}
 }
 
 func handleRequest(conn net.Conn) {
-	buf := make([]byte, 1024)
-	_, err := conn.Read(buf)
-	if err != nil {
-		fmt.Printf("Error reading: %v\n", err)
+	defer conn.Close()
+	if _, err := io.Copy(conn, conn); err != nil {
+		log.Fatalln(err)
 	}
-	conn.Write(buf)
-	conn.Close()
 }