From 3dbrew
Revision as of 20:20, 29 November 2012 by Elisherer (talk | contribs) (→‎ARC header: oops)
Jump to navigation Jump to search

This page documents the format of ARC.


ARC files are archives. Containers of files compressed with LZ-10 (more compression methods might be available).

This is very similiar to NARC (the DS archives).

ARC header

Offset Size Type Description
0x000 4 char[4] Magic Number 'darc'
0x004 2 uint16 Endianess (=0xFFFE: Little)
0x006 2 uint16 Header's length
0x008 4 uint32 Unknown (= 0x01000000 ?)
0x00C 4 uint32 File's length
0x010 4 uint32 File table offset (from the beginning of the file)
0x014 4 uint32 File table length
0x018 4 uint32 Files data offset

File table

The file table starts at 0x01C.

Each file struct consists of 3 uint32:

Offset Size Type Description
0x00C 4 uint32 Compressed file name offset (from the end of the table, padded to 0x10)

if (MSB is high) then this is a folder (i.e. first two nodes 'null' & '.')

0x004 4 uint32 Compressed file offset
0x008 4 uint32 Compressed file length
 * First two nodes in the file table are ‘null’ and ‘.’ both have compressed file length of 7.

Files Data

 * Each file is compressed using LZ-10. (Starts with 0x10 and followed by uint24 of the uncompressed file size).
 * Each file's end is padded to 0x10 besides the last one which ends with EOF.