Fix racy modification of NotFoundHandler.

kisielk · kisielk · commit 854d482e2650 · 2014-06-04T14:12:38.000-07:00
diff --git a/mux.go b/mux.go
@@ -87,10 +87,10 @@ func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		setCurrentRoute(req, match.Route)
 	}
 	if handler == nil {
-		if r.NotFoundHandler == nil {
-			r.NotFoundHandler = http.NotFoundHandler()
-		}
 		handler = r.NotFoundHandler
+		if handler == nil {
+			handler = http.NotFoundHandler()
+		}
 	}
 	if !r.KeepContext {
 		defer context.Clear(req)

Original file line number	Diff line number	Diff line change
`@@ -87,10 +87,10 @@ func (r Router) ServeHTTP(w http.ResponseWriter, req http.Request) {`
`87`	`87`	`setCurrentRoute(req, match.Route)`
`88`	`88`	`}`
`89`	`89`	`if handler == nil {`
`90`		`- if r.NotFoundHandler == nil {`
`91`		`- r.NotFoundHandler = http.NotFoundHandler()`
`92`		`- }`
`93`	`90`	`handler = r.NotFoundHandler`
	`91`	`+ if handler == nil {`
	`92`	`+ handler = http.NotFoundHandler()`
	`93`	`+ }`
`94`	`94`	`}`
`95`	`95`	`if !r.KeepContext {`
`96`	`96`	`defer context.Clear(req)`