can we reverse engineer an old build that I lost the source files?

[dpjpandone]

Can we do this? I no longer have the laptop I was using for development a few years ago, but I DO have the test builds that I published at the time. Is there a way to extract the source from one of those test builds?

[petabyte]

You couldn't get the source code. You might be able to throw it in Ghidra and use that to help you rewrite the code.

[names_are_hard]

It might be possible to get the source.  The mercurial build system logged source code changes as part of the build, and copied them into one of the binaries.  I haven't worked with this in much detail and can't remember the limitations.

See parts in the make system around "version.bin", there's some hg logging command that creates it.

[dpjpandone]

It might be possible to get the source.  The mercurial build system logged source code changes as part of the build, and copied them into one of the binaries.  I haven't worked with this in much detail and can't remember the limitations.

See parts in the make system around "version.bin", there's some hg logging command that creates it.

so I actually found the Hard drive with my old source today!!!! BUT!!!!

All the files are gibberish!

for example, here is the content of my old features.h:

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I think that old hard drive has seen better days.

It's so fucking weird because all my arduino sketches and sqjpegs and stuff are fine, wtf happened to my ML files?

any advice for recovering these files?

[names_are_hard]

Travel back in time and use a source control system.

You might be able to pull stuff out of hg's log, if you used that locally.  Repairing files is unlikely.  Some filesystems allow reverting to earlier versions but this is rare.  Maybe disk repair tools will help, this depends a lot on filesystem, OS etc.