From ada8dee0aa6a5d2b730ece3d20d447bf968bb90f Mon Sep 17 00:00:00 2001
From: Erik Brakkee <erik@brakkee.org>
Date: Thu, 18 Jul 2024 21:25:00 +0200
Subject: [PATCH] further generalizatio of synchronizing two streams of data.

---
 cmd/tcptows/tcptows.go | 23 +----------------------
 cmd/wstotcp/wstotcp.go | 27 +--------------------------
 pkg/iowrappers/sync.go | 31 +++++++++++++++++++++++++++++++
 3 files changed, 33 insertions(+), 48 deletions(-)
 create mode 100644 pkg/iowrappers/sync.go

diff --git a/cmd/tcptows/tcptows.go b/cmd/tcptows/tcptows.go
index 3f36621..f30a797 100644
--- a/cmd/tcptows/tcptows.go
+++ b/cmd/tcptows/tcptows.go
@@ -3,7 +3,6 @@ package main
 import (
 	"cidebug/pkg/iowrappers"
 	"github.com/gorilla/websocket"
-	"io"
 	"log"
 	"net"
 )
@@ -19,27 +18,7 @@ func handleConnection(tcpConn net.Conn, wsURL string) {
 	}
 	defer wsConn.Close()
 
-	waitChannel := make(chan bool)
-
-	go func() {
-		defer func() {
-			waitChannel <- true
-		}()
-		_, err = io.Copy(tcpConn, wsConn)
-		if err != nil {
-			log.Printf("error %v", err)
-		}
-	}()
-
-	go func() {
-		defer func() {
-			waitChannel <- true
-		}()
-		_, err = io.Copy(wsConn, tcpConn)
-		log.Printf("Error %v", err)
-	}()
-
-	<-waitChannel
+	iowrappers.SynchronizeStreams(wsConn, tcpConn)
 }
 
 func main() {
diff --git a/cmd/wstotcp/wstotcp.go b/cmd/wstotcp/wstotcp.go
index a8e401d..7c81b79 100644
--- a/cmd/wstotcp/wstotcp.go
+++ b/cmd/wstotcp/wstotcp.go
@@ -4,7 +4,6 @@ import (
 	"cidebug/pkg/iowrappers"
 	"fmt"
 	"github.com/gorilla/websocket"
-	"io"
 	"log"
 	"net"
 	"net/http"
@@ -42,29 +41,5 @@ func handleWebSocket(w http.ResponseWriter, r *http.Request, tcpConn net.Conn) {
 	}
 	defer wsConn.Close()
 
-	waitChannel := make(chan bool)
-
-	// Read message from WebSocket
-	go func() {
-		defer func() {
-			waitChannel <- true
-		}()
-		_, err := io.Copy(tcpConn, wsConn)
-		if err != nil {
-			log.Printf("Error occurred %v", err)
-		}
-	}()
-
-	go func() {
-		defer func() {
-			waitChannel <- true
-		}()
-		_, err := io.Copy(wsConn, tcpConn)
-		if err != nil {
-			log.Printf("Error occurred %v", err)
-		}
-	}()
-
-	<-waitChannel
-	log.Println("Connection closed")
+	iowrappers.SynchronizeStreams(tcpConn, wsConn)
 }
diff --git a/pkg/iowrappers/sync.go b/pkg/iowrappers/sync.go
new file mode 100644
index 0000000..20a7820
--- /dev/null
+++ b/pkg/iowrappers/sync.go
@@ -0,0 +1,31 @@
+package iowrappers
+
+import (
+	"io"
+	"log"
+)
+
+func SynchronizeStreams(stream1, stream2 io.ReadWriter) {
+	waitChannel := make(chan bool)
+
+	go func() {
+		defer func() {
+			waitChannel <- true
+		}()
+		_, err := io.Copy(stream1, stream2)
+		if err != nil {
+			log.Printf("error %v", err)
+		}
+	}()
+
+	go func() {
+		defer func() {
+			waitChannel <- true
+		}()
+		_, err := io.Copy(stream2, stream1)
+		log.Printf("Error %v", err)
+	}()
+
+	<-waitChannel
+	log.Println("Connection closed")
+}