FizzBuzz OS by mssola

Project Description

FizzBuzz OS (or just fbos) is an idea I've had in order to better grasp the fundamentals of the low level of a RISC-V machine. In practice, I'd like to build a small Operating System kernel that is able to launch three processes: one that simply prints "Fizz", another that prints "Buzz", and the third which prints "FizzBuzz". These processes are unaware of each other and it's up to the kernel to schedule them by using the timer interrupts as given on openSBI (fizz on % 3 seconds, buzz on % 5 seconds, and fizzbuzz on % 15 seconds).

This kernel provides just one system call, write, which allows any program to pass the string to be written into stdout.

This project is free software and you can find it here.

Goal for this Hackweek

• Better understand the RISC-V SBI interface.
• Better understand RISC-V in privileged mode.
• Have fun.

Resources

• SBI v2.0 ratified specification
• Blog post on SBI
• mssola/fbos

Results

The project was a resounding success Lots of learning, and the initial target was met.

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Symbol Relations by hli

Description

There are tools to build function call graphs based on parsing source code, for example, cscope.

This project aims to achieve a similar goal by directly parsing the disasembly (i.e. objdump) of a compiled binary. The assembly code is what the CPU sees, therefore more "direct". This may be useful in certain scenarios, such as gdb/crash debugging.

Detailed description and Demos can be found in the README file:

Supports x86 for now (because my customers only use x86 machines), but support for other architectures can be added easily.

Tested with python3.6

Goals

Any comments are welcome.

Resources

https://github.com/lhb-cafe/SymbolRelations

symrellib.py: mplements the symbol relation graph and the disassembly parser

symrel_tracer*.py: implements tracing (-t option)

symrel.py: "cli parser"

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Port some classic game to Linux by MDoucha

Let's pick some old classic game, reverse engineer the data formats and game rules and write an open source engine for it from scratch. Some games from 1990s are simple enough that we could have a playable prototype by the end of the week.

Write which games you'd like to hack on in the comments. Don't forget to check e.g. on Open Source Game Clones, Github and SourceForge whether the game is ported already.

Hack Week 24 - Master of Orion II: Battle at Antares & Chaos Overlords

Work on Master of Orion II continues but we can hack more than one game. Chaos Overlords is a dystopian, lighthearted, cyberpunk turn-based strategy game originally released in 1996 for Windows 95 and Mac OS. The player takes on the role of a Chaos Overlord, attempting to control a city. Gameplay involves hiring mercenary gangs and deploying them on an 8-by-8 grid of city sectors to generate income, occupy sectors and take over the city.

How to ~~install & play~~ observe the decompilation progress:

• Clone the Git repository
• A playable reimplementation does not exist yet, but when it does, it will be linked in the repository mentioned above.

Further work needed:

• Analyze the remaining unknown data structures, most of which are related to the AI.
• Decompile the AI completely. The strong AI is part of the appeal of the game. It cannot be left out.
• Reimplement the game.

Hack Week 20, 21, 22 & 23 - Master of Orion II: Battle at Antares

Master of Orion II is one of the greatest turn-based 4X games of the 1990s. Explore the galaxy, colonize planets, research new technologies, fight space monsters and alien empires and in the end, become the ruler of the galaxy one way or another.

How to install & play:

• Clone the Git repository
• Run ./bootstrap; ./configure; make && make install
• Copy all *.LBX files from the original Master of Orion II to the installation data directory (/usr/local/share/openorion2 by default)
• Run openorion2

Further work needed:

• Analyze the rest of the original savegame format and a few remaining data files.
• Implement most of the game. The open source engine currently supports only loading saved games from the original version and viewing the galaxy map, fleet management and list of known planets.

Hack Week 19 - Signus: The Artifact Wars

Signus is a Czech turn-based strategy game similar to Panzer General or Battle Isle series. Originally published in 1998 and open-sourced by the original developers in 2003.

How to install & play:

• Clone the Git repository
• Run ./bootstrap; ./configure; make && make install in both signus and signus-data directories.
• Run signus

Further work needed:

• Create openSUSE package
• Implement full support for original game data (the open source version uses slightly different data file contents but original game data can be converted using a script).

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