Define tcpip.Payloader in terms of io.Reader

Fixes #1509.

PiperOrigin-RevId: 353295589

2 files changed, 13 insertions, 18 deletions

diff --git a/pkg/tcpip/sample/tun_tcp_connect/BUILD b/pkg/tcpip/sample/tun_tcp_connect/BUILD
index cf0a5fefe..db9b91815 100644
--- a/pkg/tcpip/sample/tun_tcp_connect/BUILD
+++ b/pkg/tcpip/sample/tun_tcp_connect/BUILD
@@ -8,7 +8,6 @@ go_binary(
     visibility = ["//:sandbox"],
     deps = [
         "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
         "//pkg/tcpip/header",
         "//pkg/tcpip/link/fdbased",
         "//pkg/tcpip/link/rawfile",
diff --git a/pkg/tcpip/sample/tun_tcp_connect/main.go b/pkg/tcpip/sample/tun_tcp_connect/main.go
index 3b4f900e3..3d9954c84 100644
--- a/pkg/tcpip/sample/tun_tcp_connect/main.go
+++ b/pkg/tcpip/sample/tun_tcp_connect/main.go
@@ -41,7 +41,7 @@
 package main
 
 import (
-	"bufio"
+	"bytes"
 	"fmt"
 	"log"
 	"math/rand"
@@ -51,7 +51,6 @@ import (
 	"time"
 
 	"gvisor.dev/gvisor/pkg/tcpip"
-	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
 	"gvisor.dev/gvisor/pkg/tcpip/link/fdbased"
 	"gvisor.dev/gvisor/pkg/tcpip/link/rawfile"
@@ -71,24 +70,21 @@ func writer(ch chan struct{}, ep tcpip.Endpoint) {
 		close(ch)
 	}()
 
-	r := bufio.NewReader(os.Stdin)
-	for {
-		v := buffer.NewView(1024)
-		n, err := r.Read(v)
-		if err != nil {
-			return
-		}
-
-		v.CapLength(n)
-		for len(v) > 0 {
-			n, err := ep.Write(tcpip.SlicePayload(v), tcpip.WriteOptions{})
-			if err != nil {
-				fmt.Println("Write failed:", err)
-				return
+	var b bytes.Buffer
+	if err := func() error {
+		for {
+			if _, err := b.ReadFrom(os.Stdin); err != nil {
+				return fmt.Errorf("b.ReadFrom failed: %w", err)
 			}
 
-			v.TrimFront(int(n))
+			for b.Len() != 0 {
+				if _, err := ep.Write(&b, tcpip.WriteOptions{Atomic: true}); err != nil {
+					return fmt.Errorf("ep.Write failed: %s", err)
+				}
+			}
 		}
+	}(); err != nil {
+		fmt.Println(err)
 	}
 }