shibbo/magikoopa

Compiles custom code for 3ds games and injects it into existing code.bin files and patches the exheader

Magikoopa

Compiles custom code for 3ds games and injects it into existing code.bin files and patches the exheader

Motivation for this is to create a NSMB2 hack with fully custom code. In theory this should work with all other games as well tho.

Work in progress. Should be in a kinda working state now. Might still have bugs that wait to be reported :)

You can find examples on how to use Magikoopa in combination with NSMB2 here: https://github.com/RicBent/Magikoopa-NSMB2-Examples/

Getting started

• Build the project in QtCreator.
• Run Magikoopa in the build directory.

Hooks

Hooks can be specified with hks files in a patch's working directory. The format is similar to YAML:

hook_name_1:
  type: xxx
  link: false
  addr: 0x00430988
  func: FunctionNameHere
hook_name_2:
  ...

There are several types of hooks.

Type	Description
branch	Branch to a function (overwrites the original instruction)
softbranch	Branch to a function (preserves the original instruction)
patch	Patch data at an offset
symbol	Write the address of a symbol

The following parameters are common to all hook types:

Parameter	Description
addr	Hook address

Branch hooks

Parameter	Description
link	true to make a BL instruction, false for B
func	(1) Branch destination function name. This will be converted to an address using the symbol table.
dest	(2) Branch destination address

link and one of func and dest are required parameters.

Soft-branch hooks

Parameter	Description
func	(1) Branch destination function name. This will be converted to an address using the symbol table.
dest	(2) Branch destination address
opcode	"pre", "post" or "ignore". Defaults to "ignore" if not specified. "pre" to branch to func/dest after the original instruction, "post" to branch before the original instruction.

One of func and dest are required parameters.

Patch hooks

Parameter	Description
data	(1) Data to insert (in hexadecimal)
src	(2) Symbol name of data to insert
len	(2) Length of data to insert

data, or both src and len, are required parameters.

Thanks to

• Dirbaio -- Creator of the NSMBDS asm patch template which was used as a basis
• StapleButter -- Partial coding of the Filesystem classes
• Icons8 -- Icons (https://icons8.com/)