diff --git a/src/config_util.rs b/src/config_util.rs
index 73d35a7..921b91a 100644
--- a/src/config_util.rs
+++ b/src/config_util.rs
@@ -1,4 +1,5 @@
 use std::{
+    cmp::{min, max, },
     fs,
     path::Path,
 };
@@ -98,13 +99,10 @@ impl OSSBackupdConfigItem {
     }
 
     pub fn get_safe_backup_count(&self) -> usize {
-        let mut backup_count = self.backup_count.unwrap_or(10u32) as usize;
-        if backup_count < 1_usize {
-            backup_count = 1_usize;
-        } else if backup_count > 10000_usize {
-            backup_count = 10000_usize;
-        }
-        backup_count
+        min(
+            max(self.backup_count.unwrap_or(10u32) as usize, 1_usize),
+            1000_usize
+        )
     }
 }
 
@@ -133,7 +131,7 @@ pub fn remove_start_end_slash(s: &str) -> String {
     while ss.ends_with("/") {
         ss = &ss[0..(ss.len() - 1)];
     }
-    ss.to_string()
+    ss.to_owned()
 }
 
 pub fn parse_config(config_json: &json::JsonValue) -> OSSBackupdConfig {