ws,wsutil: more explicit returns (#167)

Author: cristaloleg

dialer.go

@@ -146,7 +146,7 @@ type Dialer struct {
 func (d Dialer) Dial(ctx context.Context, urlstr string) (conn net.Conn, br *bufio.Reader, hs Handshake, err error) {
 	u, err := url.ParseRequestURI(urlstr)
 	if err != nil {
-		return
+		return nil, nil, hs, err
 	}
 
 	// Prepare context to dial with. Initially it is the same as original, but
@@ -164,7 +164,7 @@ func (d Dialer) Dial(ctx context.Context, urlstr string) (conn net.Conn, br *buf
 		}
 	}
 	if conn, err = d.dial(dialctx, u); err != nil {
-		return conn, br, hs, err
+		return conn, nil, hs, err
 	}
 	defer func() {
 		if err != nil {
@@ -229,7 +229,7 @@ func (d Dialer) dial(ctx context.Context, u *url.URL) (conn net.Conn, err error)
 		hostname, addr := hostport(u.Host, ":443")
 		conn, err = dial(ctx, "tcp", addr)
 		if err != nil {
-			return
+			return nil, err
 		}
 		tlsClient := d.TLSClient
 		if tlsClient == nil {

http.go

@@ -91,7 +91,6 @@ func httpParseRequestLine(line []byte) (req httpRequestLine, err error) {
 	req.major, req.minor, ok = httpParseVersion(proto)
 	if !ok {
 		err = ErrMalformedRequest
-		return req, err
 	}
 	return req, err
 }
@@ -127,25 +126,25 @@ func httpParseVersion(bts []byte) (major, minor int, ok bool) {
 	case bytes.Equal(bts, httpVersion1_1):
 		return 1, 1, true
 	case len(bts) < 8:
-		return
+		return 0, 0, false
 	case !bytes.Equal(bts[:5], httpVersionPrefix):
-		return
+		return 0, 0, false
 	}
 
 	bts = bts[5:]
 
 	dot := bytes.IndexByte(bts, '.')
 	if dot == -1 {
-		return
+		return 0, 0, false
 	}
 	var err error
 	major, err = asciiToInt(bts[:dot])
 	if err != nil {
-		return
+		return major, 0, false
 	}
 	minor, err = asciiToInt(bts[dot+1:])
 	if err != nil {
-		return
+		return major, minor, false
 	}
 
 	return major, minor, true
@@ -156,7 +155,7 @@ func httpParseVersion(bts []byte) (major, minor int, ok bool) {
 func httpParseHeaderLine(line []byte) (k, v []byte, ok bool) {
 	colon := bytes.IndexByte(line, ':')
 	if colon == -1 {
-		return
+		return nil, nil, false
 	}
 
 	k = btrim(line[:colon])

read.go

@@ -84,7 +84,7 @@ func ReadHeader(r io.Reader) (h Header, err error) {
 		copy(h.Mask[:], bts)
 	}
 
-	return h, err
+	return h, nil
 }
 
 // ReadFrame reads a frame from r.

server.go

@@ -451,12 +451,12 @@ func (u Upgrader) Upgrade(conn io.ReadWriter) (hs Handshake, err error) {
 	// Read HTTP request line like "GET /ws HTTP/1.1".
 	rl, err := readLine(br)
 	if err != nil {
-		return
+		return hs, err
 	}
 	// Parse request line data like HTTP version, uri and method.
 	req, err := httpParseRequestLine(rl)
 	if err != nil {
-		return
+		return hs, err
 	}
 
 	// Prepare stack-based handshake header list.
@@ -640,7 +640,7 @@ func (u Upgrader) Upgrade(conn io.ReadWriter) (hs Handshake, err error) {
 		httpWriteResponseError(bw, err, code, header.WriteTo)
 		// Do not store Flush() error to not override already existing one.
 		_ = bw.Flush()
-		return
+		return hs, err
 	}
 
 	httpWriteResponseUpgrade(bw, nonce, hs, header.WriteTo)

server_test.s

@@ -45,7 +45,7 @@ func (c *cbuf) split(p []byte) (head, tail []byte) {
 		x := n - len(c.buf)
 		head = p[:x]
 		tail = p[x:]
-		return
+		return head, tail
 	}
 	return nil, p
 }

wsflate/cbuf.go

@@ -27,20 +27,20 @@ type Extension struct {
 // nil error.
 func (n *Extension) Negotiate(opt httphead.Option) (accept httphead.Option, err error) {
 	if !bytes.Equal(opt.Name, ExtensionNameBytes) {
-		return
+		return accept, nil
 	}
 	if n.accepted {
 		// Negotiate might be called multiple times during upgrade.
 		// We stick to first one accepted extension since they must be passed
 		// in ordered by preference.
-		return
+		return accept, nil
 	}
 
 	want := n.Parameters
 
 	// NOTE: Parse() resets params inside, so no worries.
-	if err = n.params.Parse(opt); err != nil {
-		return
+	if err := n.params.Parse(opt); err != nil {
+		return accept, err
 	}
 	{
 		offer := n.params.ServerMaxWindowBits
@@ -49,7 +49,7 @@ func (n *Extension) Negotiate(opt httphead.Option) (accept httphead.Option, err
 			// A server declines an extension negotiation offer
 			// with this parameter if the server doesn't support
 			// it.
-			return
+			return accept, nil
 		}
 	}
 	{
@@ -60,14 +60,14 @@ func (n *Extension) Negotiate(opt httphead.Option) (accept httphead.Option, err
 		offer := n.params.ClientMaxWindowBits
 		want := want.ClientMaxWindowBits
 		if want > offer {
-			return
+			return accept, nil
 		}
 	}
 	{
 		offer := n.params.ServerNoContextTakeover
 		want := want.ServerNoContextTakeover
 		if offer && !want {
-			return
+			return accept, nil
 		}
 	}
 

wsflate/extension.go

@@ -111,7 +111,7 @@ func (r *Reader) Read(p []byte) (n int, err error) {
 
 	n, err = r.frame.Read(p)
 	if err != nil && err != io.EOF {
-		return
+		return n, err
 	}
 	if err == nil && r.raw.N != 0 {
 		return n, nil
@@ -215,7 +215,7 @@ func (r *Reader) NextFrame() (hdr ws.Header, err error) {
 				// Ensure that src is empty.
 				_, err = io.Copy(ioutil.Discard, &r.raw)
 			}
-			return
+			return hdr, err
 		}
 	} else {
 		r.opCode = hdr.OpCode