gcmod is a tool for extracting the contents of and rebuilding GameCube ROMs, as well as for getting all sorts of useful information about a ROM without ever extracting the contents.
I'm working on adding more features to actually help the modding process go smoother, and eventually, I would like it to also be a powerful tool for creating mods for GameCube games. I'd also like to create a Rust API for all of this at some point, but that's a slightly lower priority right now.
If you don't have Rust installed, you'll need to do that first. I recommend installing it via rustup. gcmod works on macOS and Linux, but there is currently no Windows support. I'd like to add that eventually, but I don't have a Windows machine at the moment.
To install gcmod, download the project and run cargo install in the project's directory. This will place gcmod at ~/.cargo/bin/gcmod, so you will need to make sure ~/.cargo/bin is in your $PATH environment variable.
I plan on adding a better installation method eventually, as well as distributing pre-built binaries.
gcmod --help will give you an overview of the available subcommands.
disasm Disassemble the main DOL file from a ROM.
extract Extract a ROM's contents to disk.
help Prints this message or the help of the given subcommand(s)
info Display information about the ROM.
rebuild Rebuilds a ROM.
You can also pass --help after any of these subcommands to see their usage.
$ gcmod info --help
gcmod-info
Display information about the ROM.
USAGE:
gcmod info [FLAGS] [OPTIONS] <rom_path>
FLAGS:
--help Prints help information
-h, --hex Displays numbers in hexadecimal.
-V, --version Prints version information
OPTIONS:
-o, --offset <offset> Print information about whichever section is at the given offset.
-t, --type <type> Print a given type of information about the ROM. [possible values: header, dol, fst,
apploader, layout]
ARGS:
<rom_path>
$ gcmod extract melee.iso melee_root
Writing game header...
Writing file system table...
Writing app loader...
Writing DOL header...
1209/1209 files written.
$ gcmod rebuild melee_root melee.iso
1212/1212 files added.
Here's a link to some documentation I'm working on for the GameCube ROM format: GameCube ROM Info (I don't update this very often, I need to stay on top of that...)