anchor.diff:  
   %% @doc Generate an key for backend db
   -define(gen_backend_key(_VSN, _AddrId, _Key),
  -begin
  -case _VSN of
  -?AVS_HEADER_VSN_2_2 ->
  -term_to_binary({_AddrId, _Key});
  -?AVS_HEADER_VSN_2_4 ->
  -_Key
  -end
  -end).
  +        begin
  +            case _VSN of
  +                ?AVS_HEADER_VSN_2_2 ->
  +                    term_to_binary({_AddrId, _Key});
  +                ?AVS_HEADER_VSN_2_4 ->
  +                    _Key
  +            end
  +        end).
   
   -define(AVS_HEADER_VSN,     <<?AVS_HEADER_VSN_TOBE/binary,13,10>>).
   -define(AVS_PART_OF_HEADER, <<"CHKSUM:128,KSIZE:16,BLEN_MSIZE:32,DSIZE:32,OFFSET:64,ADDRID:128,CLOCK:64,TIMESTAMP:42,DEL:1,BUF:437,CHUNK_SIZE:32,CHUNK_NUM:24,CHUNK_INDEX:24",13,10>>).
   -define(AVS_PART_OF_BODY,   <<"KEY/binary,DATA/binary",13,10>>).
   -define(AVS_PART_OF_FOOTER, <<"PADDING:64",13,10>>).
   -define(AVS_SUPER_BLOCK,    <<?AVS_HEADER_VSN/binary,
  -?AVS_PART_OF_HEADER/binary,
  -?AVS_PART_OF_BODY/binary,
  -?AVS_PART_OF_FOOTER/binary>>).
  +                              ?AVS_PART_OF_HEADER/binary,
  +                              ?AVS_PART_OF_BODY/binary,
  +                              ?AVS_PART_OF_FOOTER/binary>>).
   -define(AVS_SUPER_BLOCK_LEN, byte_size(?AVS_SUPER_BLOCK)).
   
   %% ------------------------ %%
  
positive.code: -define(ST_RUNNING, 'running').
  -define(ST_SUSPENDING, 'suspending').
  -type(compaction_state() :: ?ST_IDLING |
  ?ST_RUNNING |
  ?ST_SUSPENDING).
  
  
  -undef(EVENT_RUN).
  
negative.code: 
  %% @doc Generate a raw file path
  -define(gen_raw_file_path(_FilePath),
          lists:append([_FilePath, "_", integer_to_list(leo_date:now())])).
  
  %% @doc Retrieve object-storage info
  -define(get_obj_storage_info(_ObjStorageId),
          leo_object_storage_server:get_backend_info(_ObjStorageId, ?SERVER_OBJ_STORAGE)).
  
  
  %% @doc Diagnosis log-related definitions
  