fileLogger.go
func (f *FileLogger) fileCheck() {
	defer func() {
		if err := recover(); err != nil {
			f.lg.Printf("FileLogger's FileCheck() catch panic: %v\n", err)
		}
	}()

	if f.isMustSplit() {
		f.mu.Lock()
		defer f.mu.Unlock()

		f.split()
	}
}
func (f *FileLogger) fileCheck() {
	defer func() {
		if err := recover(); err != nil {
			f.lg.Printf("FileLogger's FileCheck() catch panic: %v\n", err)
		}
	}()

	if f.isMustSplit() {
		f.mu.Lock()
		defer f.mu.Unlock()

		f.split()
	}
}
// If the current fileLogger need to split, just split