Difference between revisions of "ExeFS"

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=== Overview ===
 
=== Overview ===
ExeFS or Executable Filesystem contains information related to the executable program, and is the part of the CXI format.  
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ExeFS or Executable Filesystem contains information related to the executable program, and is the part of the [[NCCH#CXI|CXI]] format.  
  
 
The ExeFS usually contains one or more of the following files:
 
The ExeFS usually contains one or more of the following files:

Revision as of 19:43, 18 July 2012

Overview

ExeFS or Executable Filesystem contains information related to the executable program, and is the part of the CXI format.

The ExeFS usually contains one or more of the following files:

  • .code Contains the code binary, which can be optionally reverse-LZSS compressed via an exheader flag.
  • .logo Contains distribution licensing Binary data.
  • .banner Contains the banner which homemenu uses for this CXI.
  • .icon Contains the icon which homemenu displays for this CXI.

Format

The ExeFS header is 0x200 bytes long and follows this simple structure:

START SIZE DESCRIPTION
0x00 0x80 File headers (8 headers maximum, 16 bytes each)
0x80 0x80 Reserved
0x100 0x100 File hashes (8 hashes maximum, 32 bytes each, one for each header)

File headers

There are a maximum of 8 file headers in the ExeFS format, which have the following structure:

START SIZE DESCRIPTION
0x0 0x8 File name
0x8 0x4 File offset
0xC 0x4 File size

File offsets are non-inclusive of the header's size (0x200 bytes). Also, file headers which are not used are filled with all zeros.

File hashes

Each file header has a corresponding file hash, which is the SHA256 hash calculated over the entire file contents.