The purpose of this repository is to provide a docker based workflow for using os161 source code in CS3121.

This repository contains the following:

• A copy of assignment 0 source code obtained by running cp -r ~cs3231/assigns/asst8/src . on a cse machine
• Relevant .gdbinit configurations to make os161-gdb work inside the container
• A Dockerfile for defining the build rules for the docker image
• A script to build the docker image
• A script to build the os161 kernel (should be run inside the docker container)
• A script to run a container from the build docker image

In order to build the image, run the container and compile and run the os161 kernel the following steps should be taken.

# From the root of the repo
./build_image.sh
./run_image.sh # runs and moves you into the container

# Now from inside the container
./build_kernel.sh
# the build kernel script creates the kernel in the /home/root folder
cd root

# Run the kernel
sys161 kernel

Now in order to connect gdb to the kernel for debugging, the workflow is slightly different to the workflow described in the tutorials. The main difference comes from the fact that you need to run another shell inside the running container to have access to the socket exposed by the kernel.

Here is an example that works

# These steps assume you are currently in /home inside the container
# run the kernel with -w to enable the debugger instantly
cd /home/root
sys161 -w kernel

# Now outside the container
docker exec -ti os161-ass0 bash # assume the container name is os161-ass0
# this will launch another shell inside the same running container
cd root
os161-gdb kernel
# now inside gdb
asst8 # connects to the kernel :)

Currently, the os161 source code is copied over to the image. This is less than ideal since you will need to re-build the image every time you change the source code

To make this easier, you can add the kernel compile step into the Dockerfile so the kernel is ready when the image is built

Eventually I will change the workflow so that the source code is mounted as a volume, which will allow live code editing inside the container.

The dockerfile pulls two things from the internet (again just FYI)

1. The .deb package that contains all the os161 utils
2. The sys161-asst8.conf file.

Also, the dockerfile has commented a commented out section which when uncommented will build the os161 kernel in the image itself. Useful if you always want your source code compiled when the container starts

This currently starts the container with --rm which means the container will be destroyed when you quit it, just FYI