Open source IPF implementation

[vadosnaprimer]

IPF used to be a format that only its creators supported via a library that used to be proprietary and then its source got released but it remained strictly non-commercial. Therefore it's not open source, and can't be directly included into an open source project.

For this reason, every Amiga emulator I could find supports IPF by letting users download CAPSimg separately, put it into the right place, and link it that way.

Turns out there are some open source implementations of an IPF loader, apparently based on reverse engineering the format itself (that's the case for MAME, haven't checked the others).

MAME's IPF importer amusingly was made 4 days before SPS released their code.

Another one I found is this:
https://github.com/Tom1975/CPCCore/blob/master/CPCCoreEmu/CAPSFile.cpp

MAME is perfectly capable of loading Turrican (Europe).ipf, it works fine (even though emulation is not perfect). In case Amiga needs to write to a disk, MAME offers some options that don't modify the original image.

If there are some less straightforward things about IPF that need to be tested, I'm happy to try them in MAME, just tell me what image to run (like canonical filename and hash), and what to pay attention to to see if everything actually works (I don't have a lot of experience with IPF myself).

PS: There's already a more generic issue for IPF, but midwan suggested I make a new one.