From b14960fc07e5b46a78eb747afeee0414d03d7a8a Mon Sep 17 00:00:00 2001
From: ferhat elmas <elmas.ferhat@gmail.com>
Date: Mon, 23 Dec 2019 19:09:57 +0100
Subject: [PATCH] Use empty struct to protect writing

Using empty struct for signaling is more idiomatic
compared to booleans because users might wonder
what happens on false or true. Empty struct removes
this problem.

There is also a side benefit of occupying less memory
but it should be negligible in this case.
---
 conn.go     | 12 ++++++------
 prepared.go |  4 ++--
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/conn.go b/conn.go
index 6f17cd29..807e38a4 100644
--- a/conn.go
+++ b/conn.go
@@ -244,8 +244,8 @@ type Conn struct {
 	subprotocol string
 
 	// Write fields
-	mu            chan bool // used as mutex to protect write to conn
-	writeBuf      []byte    // frame is constructed in this buffer.
+	mu            chan struct{} // used as mutex to protect write to conn
+	writeBuf      []byte        // frame is constructed in this buffer.
 	writePool     BufferPool
 	writeBufSize  int
 	writeDeadline time.Time
@@ -302,8 +302,8 @@ func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int,
 		writeBuf = make([]byte, writeBufferSize)
 	}
 
-	mu := make(chan bool, 1)
-	mu <- true
+	mu := make(chan struct{}, 1)
+	mu <- struct{}{}
 	c := &Conn{
 		isServer:               isServer,
 		br:                     br,
@@ -377,7 +377,7 @@ func (c *Conn) read(n int) ([]byte, error) {
 
 func (c *Conn) write(frameType int, deadline time.Time, buf0, buf1 []byte) error {
 	<-c.mu
-	defer func() { c.mu <- true }()
+	defer func() { c.mu <- struct{}{} }()
 
 	c.writeErrMu.Lock()
 	err := c.writeErr
@@ -444,7 +444,7 @@ func (c *Conn) WriteControl(messageType int, data []byte, deadline time.Time) er
 	case <-timer.C:
 		return errWriteTimeout
 	}
-	defer func() { c.mu <- true }()
+	defer func() { c.mu <- struct{}{} }()
 
 	c.writeErrMu.Lock()
 	err := c.writeErr
diff --git a/prepared.go b/prepared.go
index 74ec565d..c854225e 100644
--- a/prepared.go
+++ b/prepared.go
@@ -73,8 +73,8 @@ func (pm *PreparedMessage) frame(key prepareKey) (int, []byte, error) {
 		// Prepare a frame using a 'fake' connection.
 		// TODO: Refactor code in conn.go to allow more direct construction of
 		// the frame.
-		mu := make(chan bool, 1)
-		mu <- true
+		mu := make(chan struct{}, 1)
+		mu <- struct{}{}
 		var nc prepareConn
 		c := &Conn{
 			conn:                   &nc,