From 76bd0a56485c4d791b2aa6579d7c67ede5d50d20 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=A4=9A=E5=90=83=E7=82=B9=E8=8B=B9=E6=9E=9C?=
 <73388495+eatmoreapple@users.noreply.github.com>
Date: Wed, 1 Feb 2023 23:43:10 +0800
Subject: [PATCH] =?UTF-8?q?[fix]:=20=E8=A7=A3=E5=86=B3=E5=AE=9A=E6=97=B6?=
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---
 stroage.go | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/stroage.go b/stroage.go
index fe18795..b9ffd97 100644
--- a/stroage.go
+++ b/stroage.go
@@ -3,6 +3,7 @@ package openwechat
 import (
 	"io"
 	"os"
+	"sync"
 	"time"
 )
 
@@ -29,9 +30,12 @@ type HotReloadStorage io.ReadWriter
 type jsonFileHotReloadStorage struct {
 	filename string
 	file     *os.File
+	lock     sync.Mutex
 }
 
 func (j *jsonFileHotReloadStorage) Read(p []byte) (n int, err error) {
+	j.lock.Lock()
+	defer j.lock.Unlock()
 	if j.file == nil {
 		j.file, err = os.OpenFile(j.filename, os.O_RDWR, 0600)
 		if os.IsNotExist(err) {
@@ -45,21 +49,22 @@ func (j *jsonFileHotReloadStorage) Read(p []byte) (n int, err error) {
 }
 
 func (j *jsonFileHotReloadStorage) Write(p []byte) (n int, err error) {
+	j.lock.Lock()
+	defer j.lock.Unlock()
 	if j.file == nil {
 		j.file, err = os.Create(j.filename)
 		if err != nil {
 			return 0, err
 		}
 	}
-	// 为什么这里要对文件进行Truncate操作呢?
-	// 这是为了方便每次Dump的时候对文件进行重新写入, 而不是追加
-	// json序列化写入只会调用一次Write方法, 所以不要把这个方法当成io.Writer的Write方法
+	// reset offset and truncate file
 	if _, err = j.file.Seek(0, io.SeekStart); err != nil {
 		return
 	}
 	if err = j.file.Truncate(0); err != nil {
 		return
 	}
+	// json decode only write once
 	return j.file.Write(p)
 }