buildroot-vscode-devcontainer

Devcontainer config for use in vscode for Buildroot builds in a container.

Configuration

Configure container user & group

In the Dockerfile, I set up an ubuntu user that matches my host system's user & group ID. The Dockerfile configuration will work out of the box if your UID:GID is 1000:1000 on your host system. To check your IDs, you can do:

id -u
id -g

Otherwise, export your UID and GID in your .bashrc. Your user ID is set in the UID environment variable by default on an Ubuntu system. You do need to set your own group ID in an environment variable manually, so it can be read in the Dockerfile. In your ~/.bashrc, add at the end:

export UID
export GID=$(id -g)

Ubuntu version

You might want to change the Ubuntu version in the Dockerfile depending on which version of Buildroot you are using. Some combinations work out of the box, others don't. I tested building with buildroot-2021.02 with an Ubuntu 20.04 container image.

Additional packages for Buildroot

Depending on your configuration, you might need additional packages installed for your Buildroot build. For example, a different source fetching tool should be installed in the Dockerfile if needed. Packages that are specifically required to build for your target platform should be included in your target platform's defconfig file (option BR2_PACKAGE_HOST_?).

gcc-?-plugin-dev

You need to install the correct gcc-?-plugin-dev package according to what GCC version your platform's defconfig file specifies in Buildroot. This is set in the BR2_GCC_VERSION_?_X option. For example, if your target platform's defconfig specifies BR2_GCC_VERSION_10_X=y, make sure the gcc-10-plugin-dev package is installed in the Dockerfile. I included multiple versions in there by default.

vscode plugins in the devcontainer

You might want to add a extensions section in devcontainer.json, so you can use the required extensions for your work in the devcontainer.

Mounted files & directories

The following are mounted into the container:

• SSH_AUTH_SOCK: allows you to use your SSH keys that are on your host system for cloning private packages in your Buildroot build
• .gitconfig: allows you to use your identity on your host system with git inside the devcontainer e.g. for commits to your Buildroot repository fork
• buildroot directory: the Buildroot directory that you manually need to clone/copy into this directory

Setup

Make sure you have the prerequisites that are listed in the Visual Studio Code Guide.

Clone the Buildroot repository (probably you want to clone your fork/private version with your custom config instead) in this directory.

git clone git://git.busybox.net/buildroot

Open this directory in vscode and bring up the command palette (default Ctrl+Shift+P). Select Dev Containers: Reopen in Container.

You can now start working with Buildroot; for example to build the raspberrypi4_defconfig with Buildroot version 2021.02:

git checkout 2021.02
make raspberrypi4_defconfig && make