add fn get_safe_backup_count

src/config_util.rs

@@ -93,6 +93,16 @@ impl OSSBackupdConfigItem {
             None => "default_file_name".to_owned(),
         }
     }
+
+    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
+    }
 }
 
 fn real_make_oss_key(oss_backupd_config: &OSSBackupdConfig, oss_backupd_config_item: &OSSBackupdConfigItem, suffix: &str) -> String {