From 5c3d333f10c7238cae9b8ed1aabdb8c8ab6a7ebc Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Fri, 5 Jul 2019 07:54:25 +0200
Subject: tun: windows: registration of write buffer no longer required

---
 tun/tun_windows.go | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

(limited to 'tun/tun_windows.go')

diff --git a/tun/tun_windows.go b/tun/tun_windows.go
index f0acc09..4ae5cf0 100644
--- a/tun/tun_windows.go
+++ b/tun/tun_windows.go
@@ -11,11 +11,11 @@ import (
 	"io"
 	"os"
 	"sync"
-	"sync/atomic"
 	"time"
 	"unsafe"
 
 	"golang.org/x/sys/windows"
+
 	"golang.zx2c4.com/wireguard/tun/wintun"
 )
 
@@ -42,7 +42,6 @@ type NativeTun struct {
 	wt                        *wintun.Wintun
 	tunFileRead               *os.File
 	tunFileWrite              *os.File
-	haveRegisteredWriteBuffer int32
 	tunLock                   sync.Mutex
 	close                     bool
 	rdBuff                    *exchgBufRead
@@ -142,7 +141,6 @@ func (tun *NativeTun) openTUN() error {
 			}
 			return err
 		}
-		atomic.StoreInt32(&tun.haveRegisteredWriteBuffer, 0)
 	}
 	return nil
 }
@@ -321,15 +319,6 @@ func (tun *NativeTun) Flush() error {
 			return err
 		}
 
-		if atomic.CompareAndSwapInt32(&tun.haveRegisteredWriteBuffer, 0, 1) {
-			firstSize := (*uint32)(unsafe.Pointer(&tun.wrBuff.data[0]))
-			saved := *firstSize
-			*firstSize = 0
-			// Set the maximum buffer length with an invalid write.
-			tun.tunFileWrite.Write(tun.wrBuff.data[:])
-			*firstSize = saved
-		}
-
 		for {
 			_, err = file.Write(tun.wrBuff.data[:tun.wrBuff.offset])
 			if err != nil {
-- 
cgit v1.2.3-59-g8ed1b