add a SetReportCaller on Logger object

exported.go

@@ -27,9 +27,7 @@ func SetFormatter(formatter Formatter) {
 // SetReportCaller sets whether the standard logger will include the calling
 // method as a field.
 func SetReportCaller(include bool) {
-	std.mu.Lock()
+	std.SetReportCaller(include)
-	defer std.mu.Unlock()
-	std.ReportCaller = include
 }
 
 // SetLevel sets the standard logger level.

logger.go

@@ -399,6 +399,12 @@ func (logger *Logger) SetOutput(output io.Writer) {
 	logger.Out = output
 }
 
+func (logger *Logger) SetReportCaller(reportCaller bool) {
+	logger.mu.Lock()
+	defer logger.mu.Unlock()
+	logger.ReportCaller = reportCaller
+}
+
 // ReplaceHooks replaces the logger hooks and returns the old ones
 func (logger *Logger) ReplaceHooks(hooks LevelHooks) LevelHooks {
 	logger.mu.Lock()