Funicular

Funicular is a system that semi-automates the creation of development environments on eclectic architectures.

"Semi-automate" means it automates what it can, and provides repeatable instructions for you to follow for what it can't.

"Eclectic architectures" is not terribly-well defined, but it includes retrocomputing and esoteric architectures. Basically, if you've got an emulator for it and install and support images for it, you might be able to install and outfit and and run a system for it, using Funicular.

It's kind of like a Vagrant for the lunatic fringe, eh?

It is currently a work in progress. The current released version of Funicular is version 0.1, but this means next to nothing.

It currently supports:

• NetBSD under QEMU
• FreeDOS under QEMU
• AmigaDOS under E-UAE

And it might, one day, support:

• Commodore 64 KERNAL under VICE
• VIC-20 KERNAL under VICE
• AppleDOS under Linapple

It is hoped that Funicular will eventually replace the discrete, ad-hoc projects NetBSD-Gondola, FreeDOS-Gondola, and Amiga-Gondola.

Concepts

Funiculars, Platforms, Architectures, EmulatorModes, Emulators

Each funicular is defined by a Funicularfile in a particular directory dedicated to that funicular (in analogy with Makefile, Vagrantfile, etc.)

A funicular defines a development environment; is generally based around a particular Platform. The Platform defines a default Architecture, which in turn defines a default EmulatorMode (which is provided by an Emulator.)

In truth, it is more complicated than that. Architectures have a many-to-many relationship with Platforms, which themselves have a many-to-many relationship with EmulatorModes (which have a many-to-one relationship with an Emulator.)

Examples:

• NetBSD and FreeDOS (Platforms) can both run on i386 (Architecture)
• NetBSD (Platform) can run on both i386 and MIPS (Architectures)
• i386 (Architecture) can be emulated by both QEMU-i386 and Bochs (EmulatorModes)
• QEMU (Emulator) can emulate both i386 and SPARC (Architectures)

Worse, Platforms and Architectures are hierarchical, but not in any clean way. Amiga Kickstart sits on top of a 680x0 core, and AmigaDOS sits on top of Kickstart. The Java platform sits on top of, potentially, many different platforms. And so forth.

So, there are lots of possibilities. But, we can stick to certain "defaults" for now; not only because they are "opinionated" (I'd rather use QEMU than Bochs) but also because it makes it a lot simpler. Hopefully we'll come up with a sane way to customize all the relationships at some point.

It is useful to remember that a funicular defines an environment (usually a development environment, with compilers, text editors, and whatever else might help you develop software.) So, there can be multiple funiculars with the exact same Platform and Architecture, but outfit differently and providing different development environments.

Images

An Image has one of several roles:

• System Image: contains one operating system; boots into that operating system, if applicable; persistent and mutable; often contains utilities; also generally contains a work area for installing and building STUFF

• Support Image: like a system image, but read-only, but required for the Platform or Architecture to operate. Often in the form of ROM images. May or may not be supplied with an Emulator, depending on licensing requirements.

• Install Image: CDROM (or other readonly) image which installs the operating system to the system-image; generally not needed after that point

• Setup Image: CDROM (or other readonly) image which contains STUFF to install and build in the work area; ephemeral (recreated by funicular as needed from acquired sources)

• Distribution Image: contains a skeletal operating system and a subset of the STUFF so built. intended to be used as a "distributed product" — for other (web) emulators, bootable USB sticks, or whatnot

Usage

To bring up a funicular, you generally follow these steps:

• Acquire an install image for the Platform (e.g. a NetBSD install ISO.)
• Acquire an appropriate Emulator (e.g. toolshelf dock @@qemu.)
• Run funicular init 4000 to create a 4G (or whatever) system image.
• Run funicular install to install the platform onto the system image.
• Run funicular setup to fetch various pieces of software and install them too on the system image.
• Run funicular start to use your funicular for whatever you want.

After install and setup, or at any time thereafter, you may wish to run funicular backup to create a compressed backup copy of the system image at that point. Restoring from such a backup will generally be faster and easier than installing or setting up again.

Certain funiculars may support creating a distribution image. To create a distribution image, you generally follow these steps:

• Make sure the funicular has been set up as above.
• Run funicular initdist 720 to create a 720K (or whatever) dist image.
• Run funicular start. It will detect that there is a dist image present, and may print out specific instructions.
• Formatting and populating the dist image is funicular-dependent. Look for instructions that might have been printed out,
• After the dist image is how you like it, shutdown the emulator using the recommended method for doing so.
• Run funicular distboot to try to boot off the dist image, if it is bootable.

Notes

funicular is written in Lua 5.1. A Funicularfile is written in the configuration subset of Lua.

funicular will use toolshelf if it is available on the host system, i.e. if the TOOLSHELF env var is set, but does not strictly require it.