From dfeef5e497b8e46aec9b7e7040f1c91111eea339 Mon Sep 17 00:00:00 2001
From: Kevin Wan <wanjunfeng@gmail.com>
Date: Mon, 29 Aug 2022 08:32:17 +0800
Subject: [PATCH] fix: thread-safe in getWriter of logx (#2319)

---
 core/logx/logs.go   | 14 ++------------
 core/logx/writer.go | 11 +++++++++++
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/core/logx/logs.go b/core/logx/logs.go
index 9af80757e..325c9370d 100644
--- a/core/logx/logs.go
+++ b/core/logx/logs.go
@@ -358,19 +358,9 @@ func errorTextSync(msg string) {
 }
 
 func getWriter() Writer {
-	var w Writer
-
-	writer.lock.RLock()
-	w = writer.writer
-	writer.lock.RUnlock()
-
+	w := writer.Load()
 	if w == nil {
-		writer.lock.Lock()
-		if writer.writer == nil {
-			writer.writer = newConsoleWriter()
-		}
-		w = writer.writer
-		writer.lock.Unlock()
+		w = writer.StoreIfNil(newConsoleWriter())
 	}
 
 	return w
diff --git a/core/logx/writer.go b/core/logx/writer.go
index cb0c121f5..08873c092 100644
--- a/core/logx/writer.go
+++ b/core/logx/writer.go
@@ -67,6 +67,17 @@ func (w *atomicWriter) Store(v Writer) {
 	w.writer = v
 }
 
+func (w *atomicWriter) StoreIfNil(v Writer) Writer {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+
+	if w.writer == nil {
+		w.writer = v
+	}
+
+	return w.writer
+}
+
 func (w *atomicWriter) Swap(v Writer) Writer {
 	w.lock.Lock()
 	defer w.lock.Unlock()