ROM Hack [Release] Hershel - portable ROM patcher

[Deleted member 425649]

This is Hershel, an .nds ROM patcher written in Python 3.5+ for the sake of portability.

Unlike xdelta3, it supports the same human-readable patch format used by OpenPatch, thus patches can be analyzed if need be. Unlike OpenPatch, it is not limited to Windows only. Still, it doesn't support .xdelta patches, and probably never will.

At the moment, it doesn't include any patches per se, but that might change in the future. Check among @Robz8's threads for those.

For a concise help message, issue:

python hershel.py -h

For now, it is able to both apply the patch on a copy of the original ROM, and to apply the patch to said ROM directly. It's also possible to manually supply a CRC-32 corresponding to the ROM whose patch you wish to apply, in case your ROM's checksum doesn't match the one annotated in the patch file.

Project source and more info: https://github.com/DMSalesman/Hershel
Download: https://github.com/DMSalesman/Hershel/releases

 

[FAST6191]

Do you have any size comparisons? Mostly with xdelta and bsdiff but if you want to do a DS file system aware format then that would be good too.
Human readable is nice and all and you can give it a little slap if you find its relocation algorithm not doing its job but that can usually be dodged by setting the search window a bit higher.

 

[Deleted member 425649]

Do you have any size comparisons? Mostly with xdelta and bsdiff but if you want to do a DS file system aware format then that would be good too.
Human readable is nice and all and you can give it a little slap if you find its relocation algorithm not doing its job but that can usually be dodged by setting the search window a bit higher.

No size comparisons at the moment; for now, this tool is as good as any other patcher, meaning that it isn't strictly for NDS ROMs; I plan to add more checks in the future, if need be.

The focus is on being portable, though, as I run most code from Android.