diff --git a/internal/caches/list_file_db.go b/internal/caches/list_file_db.go
index 5620024..7c3ae32 100644
--- a/internal/caches/list_file_db.go
+++ b/internal/caches/list_file_db.go
@@ -180,6 +180,9 @@ func (this *FileListDB) Init() error {
 	}
 
 	this.selectHashListStmt, err = this.readDB.Prepare(`SELECT "id", "hash" FROM "` + this.itemsTableName + `" WHERE id>:id ORDER BY id ASC LIMIT 2000`)
+	if err != nil {
+		return err
+	}
 
 	this.deleteByHashSQL = `DELETE FROM "` + this.itemsTableName + `" WHERE "hash"=?`
 	this.deleteByHashStmt, err = this.writeDB.Prepare(this.deleteByHashSQL)
diff --git a/internal/caches/storage_file.go b/internal/caches/storage_file.go
index d573245..ec7758a 100644
--- a/internal/caches/storage_file.go
+++ b/internal/caches/storage_file.go
@@ -767,6 +767,7 @@ func (this *FileStorage) CleanAll() error {
 		}
 	}
 
+	var dirNameReg = regexp.MustCompile(`^[0-9a-f]{2}$`)
 	for _, rootDir := range rootDirs {
 		var dir = rootDir + "/p" + types.String(this.policy.Id)
 		fp, err := os.Open(dir)
@@ -795,11 +796,7 @@ func (this *FileStorage) CleanAll() error {
 			subDir := info.Name()
 
 			// 检查目录名
-			ok, err := regexp.MatchString(`^[0-9a-f]{2}$`, subDir)
-			if err != nil {
-				return err
-			}
-			if !ok {
+			if !dirNameReg.MatchString(subDir) {
 				continue
 			}
 
diff --git a/internal/utils/get.go b/internal/utils/get.go
index ecac7ce..6630f7f 100644
--- a/internal/utils/get.go
+++ b/internal/utils/get.go
@@ -6,7 +6,7 @@ import (
 	"regexp"
 )
 
-var RegexpDigitNumber = regexp.MustCompile("^\\d+$")
+var RegexpDigitNumber = regexp.MustCompile(`^\d+$`)
 
 func Get(object interface{}, keys []string) interface{} {
 	if len(keys) == 0 {
diff --git a/internal/utils/ranges/range_test.go b/internal/utils/ranges/range_test.go
index 73ec1b3..29df200 100644
--- a/internal/utils/ranges/range_test.go
+++ b/internal/utils/ranges/range_test.go
@@ -67,10 +67,3 @@ func TestRange_ComposeContentRangeHeader(t *testing.T) {
 	var r = rangeutils.NewRange(1, 100)
 	t.Log(r.ComposeContentRangeHeader("1000"))
 }
-
-func TestRange_SetLength(t *testing.T) {
-	var r = rangeutils.NewRange(1, 100)
-	t.Log(r)
-
-	t.Log(r.SetLength(1024))
-}
diff --git a/internal/waf/rule.go b/internal/waf/rule.go
index 9bff108..dd927a4 100644
--- a/internal/waf/rule.go
+++ b/internal/waf/rule.go
@@ -362,13 +362,13 @@ func (this *Rule) Test(value interface{}) bool {
 		return types.Float64(value) != this.floatValue
 	case RuleOperatorEqString:
 		if this.IsCaseInsensitive {
-			return strings.ToLower(types.String(value)) == strings.ToLower(this.Value)
+			return strings.EqualFold(types.String(value), this.Value)
 		} else {
 			return types.String(value) == this.Value
 		}
 	case RuleOperatorNeqString:
 		if this.IsCaseInsensitive {
-			return strings.ToLower(types.String(value)) != strings.ToLower(this.Value)
+			return !strings.EqualFold(types.String(value), this.Value)
 		} else {
 			return types.String(value) != this.Value
 		}