[v4] hide access to internal mutex (#193)

* changed embedded mutex to private field

* changed embedded mutex to private field

grpc.go

@@ -38,7 +38,7 @@ type grpcClient struct {
 	funcStream client.FuncStream
 	pool       *ConnPool
 	opts       client.Options
-	sync.RWMutex
+	mu         sync.RWMutex
 	init       bool
 }
 
@@ -361,8 +361,8 @@ func (g *grpcClient) maxSendMsgSizeValue() int {
 }
 
 func (g *grpcClient) newCodec(ct string) (codec.Codec, error) {
-	g.RLock()
-	defer g.RUnlock()
+	g.mu.RLock()
+	defer g.mu.RUnlock()
 
 	if idx := strings.IndexRune(ct, ';'); idx >= 0 {
 		ct = ct[:idx]
@@ -398,10 +398,10 @@ func (g *grpcClient) Init(opts ...client.Option) error {
 
 	// update pool configuration if the options changed
 	if size != g.opts.PoolSize || ttl != g.opts.PoolTTL {
-		g.pool.Lock()
+		g.pool.mu.Lock()
 		g.pool.size = g.opts.PoolSize
 		g.pool.ttl = int64(g.opts.PoolTTL.Seconds())
-		g.pool.Unlock()
+		g.pool.mu.Unlock()
 	}
 
 	g.funcCall = g.fnCall

grpc_pool.go

@@ -16,7 +16,7 @@ type ConnPool struct {
 	ttl        int64
 	maxStreams int
 	maxIdle    int
-	sync.Mutex
+	mu         sync.Mutex
 }
 
 type streamsPool struct {
@@ -64,7 +64,7 @@ func (p *ConnPool) Get(ctx context.Context, addr string, opts ...grpc.DialOption
 		addr = addr[strings.Index(addr, ":")+3:]
 	}
 	now := time.Now().Unix()
-	p.Lock()
+	p.mu.Lock()
 	sp, ok := p.conns[addr]
 	if !ok {
 		sp = &streamsPool{head: &PoolConn{}, busy: &PoolConn{}, count: 0, idle: 0}
@@ -125,10 +125,10 @@ func (p *ConnPool) Get(ctx context.Context, addr string, opts ...grpc.DialOption
 		}
 		//  a good conn
 		conn.streams++
-		p.Unlock()
+		p.mu.Unlock()
 		return conn, nil
 	}
-	p.Unlock()
+	p.mu.Unlock()
 
 	// nolint (TODO need fix)  create new conn)
 	cc, err := grpc.DialContext(ctx, addr, opts...)
@@ -138,24 +138,24 @@ func (p *ConnPool) Get(ctx context.Context, addr string, opts ...grpc.DialOption
 	conn = &PoolConn{ClientConn: cc, err: nil, addr: addr, pool: p, sp: sp, streams: 1, created: time.Now().Unix(), pre: nil, next: nil, in: false}
 
 	//  add conn to streams pool
-	p.Lock()
+	p.mu.Lock()
 	if sp.count < p.size {
 		addConnAfter(conn, sp.head)
 	}
-	p.Unlock()
+	p.mu.Unlock()
 
 	return conn, nil
 }
 
 func (p *ConnPool) Put(conn *PoolConn, err error) {
-	p.Lock()
+	p.mu.Lock()
 	p, sp, created := conn.pool, conn.sp, conn.created
 	//  try to add conn
 	if !conn.in && sp.count < p.size {
 		addConnAfter(conn, sp.head)
 	}
 	if !conn.in {
-		p.Unlock()
+		p.mu.Unlock()
 		conn.ClientConn.Close()
 		return
 	}
@@ -173,13 +173,13 @@ func (p *ConnPool) Put(conn *PoolConn, err error) {
 		now := time.Now().Unix()
 		if err != nil || sp.idle >= p.maxIdle || now-created > p.ttl {
 			removeConn(conn)
-			p.Unlock()
+			p.mu.Unlock()
 			conn.ClientConn.Close()
 			return
 		}
 		sp.idle++
 	}
-	p.Unlock()
+	p.mu.Unlock()
 }
 
 func (conn *PoolConn) Close() {

stream.go

@@ -19,7 +19,7 @@ type grpcStream struct {
 	response client.Response
 	close    func(err error)
 	conn     *PoolConn
-	sync.RWMutex
+	mu       sync.RWMutex
 	closed   bool
 }
 
@@ -88,15 +88,15 @@ func (g *grpcStream) RecvMsg(msg interface{}) (err error) {
 }
 
 func (g *grpcStream) Error() error {
-	g.RLock()
-	defer g.RUnlock()
+	g.mu.RLock()
+	defer g.mu.RUnlock()
 	return g.err
 }
 
 func (g *grpcStream) setError(e error) {
-	g.Lock()
+	g.mu.Lock()
 	g.err = e
-	g.Unlock()
+	g.mu.Unlock()
 }
 
 // Close the gRPC send stream
@@ -105,8 +105,8 @@ func (g *grpcStream) setError(e error) {
 // stream should still be able to receive after this function call
 // TODO: should the conn be closed in another way?
 func (g *grpcStream) Close() error {
-	g.Lock()
-	defer g.Unlock()
+	g.mu.Lock()
+	defer g.mu.Unlock()
 
 	if g.closed {
 		return nil
@@ -125,8 +125,8 @@ func (g *grpcStream) Close() error {
 }
 
 func (g *grpcStream) CloseSend() error {
-	g.Lock()
-	defer g.Unlock()
+	g.mu.Lock()
+	defer g.mu.Unlock()
 
 	if g.closed {
 		return nil