make headers thread safe

add reader lock

context.go

@@ -21,6 +21,7 @@ import (
 	"time"
 
 	"github.com/gin-contrib/sse"
+
 	"github.com/gin-gonic/gin/binding"
 	"github.com/gin-gonic/gin/render"
 )
@@ -71,6 +72,9 @@ type Context struct {
 	// This mutex protects Keys map.
 	mu sync.RWMutex
 
+	// This mutex protects headers map
+	hmu sync.RWMutex
+
 	// Keys is a key/value pair exclusively for the context of each request.
 	Keys map[string]any
 
@@ -954,6 +958,8 @@ func (c *Context) IsWebsocket() bool {
 }
 
 func (c *Context) requestHeader(key string) string {
+	c.hmu.Lock()
+	defer c.hmu.Unlock()
 	return c.Request.Header.Get(key)
 }
 
@@ -983,6 +989,8 @@ func (c *Context) Status(code int) {
 // It writes a header in the response.
 // If value == "", this method removes the header `c.Writer.Header().Del(key)`
 func (c *Context) Header(key, value string) {
+	c.hmu.Lock()
+	defer c.hmu.Unlock()
 	if value == "" {
 		c.Writer.Header().Del(key)
 		return