From: Adam Langley <agl@golang.org>
Date: Mon, 21 Jan 2013 16:22:08 +0000 (-0500)
Subject: crypto/cipher: don't persist errors in StreamWriter.
X-Git-Tag: go1.1rc2~1335
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=0fb6f5f21b20759a0cdbc25df0c152600fd93b4d;p=gostls13.git

crypto/cipher: don't persist errors in StreamWriter.

I messed this up from the beginning. The receiver isn't a pointer so
setting Err is useless. In order to maintain the API, just remove the
superfluous code.

Fixes #4657.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7161043
---

diff --git a/src/pkg/crypto/cipher/io.go b/src/pkg/crypto/cipher/io.go
index 76048fbf33..807e8daeaf 100644
--- a/src/pkg/crypto/cipher/io.go
+++ b/src/pkg/crypto/cipher/io.go
@@ -28,13 +28,10 @@ func (r StreamReader) Read(dst []byte) (n int, err error) {
 type StreamWriter struct {
 	S   Stream
 	W   io.Writer
-	Err error
+	Err error // unused
 }
 
 func (w StreamWriter) Write(src []byte) (n int, err error) {
-	if w.Err != nil {
-		return 0, w.Err
-	}
 	c := make([]byte, len(src))
 	w.S.XORKeyStream(c, src)
 	n, err = w.W.Write(c)
@@ -42,7 +39,6 @@ func (w StreamWriter) Write(src []byte) (n int, err error) {
 		if err == nil { // should never happen
 			err = io.ErrShortWrite
 		}
-		w.Err = err
 	}
 	return
 }