Added Docker setup to build wasp-os.

This should make it a bit easier for people to contribute. Also fixed
the documentations on how to setup on Debian, as certain recommended
packages don't exist.

Signed-off-by: Shuhao Wu <shuhao@shuhaowu.com>

docs/install.rst

@@ -9,6 +9,9 @@ Installation Guide
 Building wasp-os from source
 ----------------------------
 
+Install prerequisites
+~~~~~~~~~~~~~~~~~~~~~
+
 Building wasp-os and launching the wasp-os simulator requires Python 3.6
 (or later) and the following python modules: click, numpy, pexpect, PIL
 (or Pillow), pydbus, pygobject, pyserial, pysdl2.
@@ -50,6 +53,22 @@ tested using the `GNU-RM toolchain
     link time optimization is enabled during the MicroPython build
     (LTO is enabled by default).
 
+Install prerequisites via docker
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+To build via docker, simply invoke `tool/docker/shell` from the root directory
+after having docker installed. This will build the docker image and also drop
+you into a shell with wasp os's source code shared into the container at
+``/home/user/wasp-os``. All ``make`` commands should be usable from this shell,
+including ``make sim`` and ``make check``. Some commands that interact with
+bluetooth such as ``wasptool`` may not work, for now.
+
+.. note::
+
+    If you want to use the Docker-based setup, it is assumed that you're using
+    and x86 machine on Linux, running Xorg. Other setup may require some
+    patching for now.
+
 Fetch the code from
 `https://github.com/daniel-thompson/wasp-os <https://github.com/daniel-thompson/wasp-os>`_  and download the prerequisites:
 
@@ -69,12 +88,16 @@ list below:
     make -j `nproc` BOARD=k9 all
     make -j `nproc` BOARD=p8 all
 
+The output of these will be stored in ``build-${BOARD}/``.
+
 To rebuild the documentation:
 
 .. code-block:: sh
 
     make docs
 
+The docs will be browsable in ``docs/build/html`` as per Sphinx standards.
+
 Device Support
 --------------
 

tools/docker/Dockerfile

@@ -0,0 +1,24 @@
+FROM ubuntu:focal
+
+ARG uid
+ARG gid
+
+RUN set -xe; \
+    export DEBIAN_FRONTEND=noninteractive; \
+    apt-get update; \
+    apt-get install -y \
+      wget git build-essential pkg-config libsdl2-2.0.0 python3-click \
+      python3-numpy python3-pexpect python3-pil python3-pip python3-pydbus \
+      libcairo2-dev python3-serial unzip python3-sphinx graphviz \
+      python3-recommonmark python3-pytest \
+    ; \
+    pip3 install cbor pysdl2 pygobject cryptography;
+
+RUN set -xe; \
+    wget --progress=dot:mega -O - https://developer.arm.com/-/media/Files/downloads/gnu-rm/9-2019q4/gcc-arm-none-eabi-9-2019-q4-major-x86_64-linux.tar.bz2 | tar xjf - -C /opt
+
+RUN set -xe; \
+    addgroup --gid $gid user; \
+    adduser --gecos "" --disabled-password --uid $uid --gid $gid user;
+
+COPY setup-env.sh /etc/profile.d/setup-env.sh

tools/docker/setup-env.sh

@@ -0,0 +1,3 @@
+export PATH=/opt/gcc-arm-none-eabi-9-2019-q4-major/bin:$PATH
+
+cd ~/wasp-os

tools/docker/shell

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+docker build --build-arg uid=$UID --build-arg gid=$(id -g) -t wasp-os-dev ./tools/docker
+
+docker run \
+  -v /tmp/.X11-unix:/tmp/.X11-unix:rw \
+  -v $(pwd):/home/user/wasp-os \
+  -u user \
+  -e DISPLAY \
+  --init \
+  --device /dev/dri \
+  -it \
+  --rm \
+  wasp-os-dev \
+  bash -l