This is the Cartesi Machine that produces the score given a log for the Creepts game.

This machine uses the cartesi.so library to run the emulator. It also needs the rootfs.ext2, rom.bin, and kernel.bin files. The building process uses the toolchain Docker image. These are all products of the machine-emulator-sdk repository.

The first step is to create a filesystem with creepts engine and associated tools inside. To do that we use the genext2 tool to create a filesystem with everything that is inside the fs folder. Before doing this we must have the latest version of the creepts engine in that folder.

Building:

$ npm run build
$ make

This should produce creeptsfs.ext2.

Cleaning:

$ make clean

The emulator can be executed by having it installed locally or by using a Docker image for more convenience.

We created a convenient Docker image called cartesi/creepts-machine to make it easier to run the emulator with any game log file. You can use a Docker image published at Docker Hub, or build one yourself by doing the command below after the build steps above.

$ docker build . -t cartesi/creepts-machine

To run the emulator you need a game log file, and feed that through stdin to the container. There are some example log files at test/logs. Example below:

$ cat test/logs/log_minimum.json | docker run -i cartesi/creepts-machine --level=0

This should run the verifier and print a variety of diagnostics information on the screen:

./creepts.lua --log-backing=0.json.br.cpio --level=0 --auto-length

         .
        / \
      /    \
\---/---\  /----\
 \       X       \
  \----/  \---/---\
       \    / CARTESI
        \ /   MACHINE
         '

[    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
[    0.000000] Linux version 4.20.8 (root@toolchain-env) (gcc version 8.3.0 (crosstool-NG 1.24.0)) #2 SMP Wed Oct 2 19:40:01 UTC 2019
[    0.000000] printk: bootconsole [early0] enabled
Getting log
Getting level
Running verification
Writing results
[    4.590000] reboot: Power down
1140		4628940030

In the last line, you can see the score, followed by an empty error message, and then the value of mcycle.

You can also specify a --print-proofs argument to print the proofs at different stages of execution.

Make sure your environment variables are set so the machine-emulator and its dependencies can be found. In your development environment, go to the machine-emulator directory and type

$ eval $(make env)

to set the variables you will need.

Then, copy rootfs.ext2, rom.bin, and kernel.bin to the working directory where you have creeptsfs.ext2 and creepts.lua.

Now you need to obtain a Brotli compressed, then cpio'd log matching one of the logs in test/logs. For example:

$ ./packlog test/logs/log_minimum.json 0.json.br.cpio
$ truncate -s 1m 0.json.br.cpio

will give you one of the test logs for level 0.

You are finally ready to run the verifier on this log.

$ ./creepts.lua --log-backing=0.json.br.cpio --level=0 --auto-length

Run

$ ./creepts.lua --help

for other options.

Read the Lua source for details on the layout of the machine.

• Diego Nehab

Thank you for your interest in Cartesi! Head over to our Contributing Guidelines for instructions on how to sign our Contributors Agreement and get started with Cartesi!

Please note we have a Code of Conduct, please follow it in all your interactions with the project.

This repository and all contributions are licensed under APACHE 2.0. Please review our LICENSE file.