Run-Times

Shrinkwrap uses a “runtime” to execute all of its shell commands and allows the user to choose which runtime to use. Both the design and implementation of this is borrowed from Tuxmake.

Shrinkwrap supports the following set of runtimes:

runtime	description
null	Shell commands are executed natively on the user’s system. The user is responsible for ensuring the the required toolchain, environment variables and any other dependencies are set up.
docker	(default). Shell commands are executed in a docker container. By default, the official shrinkwrap image will be pulled and used, which contains all dependencies already setup.
docker-local	Like docker, but will only look for the container image on the local system. Will not attempt to pull over the network.
podman	Shell commands are executed in a podman container. By default, the official shrinkwrap image will be pulled and used, which contains all dependencies already setup.
podman-local	Like podman, but will only look for the container image on the local system. Will not attempt to pull over the network.

The desired runtime can be specified using the --runtime option, which is a top-level argument (must come before the command):

shrinkwrap --runtime=<name> ...

If using a container runtime (anything other than null), a custom image can optionally be specified. If omitted, the official shrinkwrap image is used:

shrinkwrap --runtime=<name> --image=<name> ...

Container Image Variants

Shrinkwrap runs on both x86_64 and aarch64 architectures, and provides multiarch container images so that the correct variant is automatically selected for your platform. Images are automatically downloaded by shrinkwrap when the docker or podman runtime is selected. Images are available on Docker Hub and can be freely downloaded without the need for an account.

image name	description
docker.io/shrinkwraptool/base-slim-nofvp:latest	Contains all toolchains and other dependencies required to build all standard configs. Can be used as a base to create an image with a custom FVP.
docker.io/shrinkwraptool/base-slim:latest	(default). As per shrinkwraptool/base-slim-nofvp:latest but also contains the Base_RevC-2xAEMvA FVP. This is suffcient for most use cases and is much smaller than the full variant.
docker.io/shrinkwraptool/base-full-nofvp:latest	Builds upon shrinkwraptool/base-slim:latest, adding aarch32 toolchains (both arm-none-eabi and arm-linux-gnueabihf). These are not needed for standard configs, but will be required if creating a custom config that includes (e.g.) SCP FW. Separated out due to big size increase.
docker.io/shrinkwraptool/base-full:latest	As per shrinkwraptool/base-full-nofvp:latest but also contains the Base_RevC-2xAEMvA FVP.

Runtime Requirements

The best way to understand the requirements for the packages available within the runtime is to look at the dockerfiles for the official shrinkwrap images. These are available at docker/Dockerfile.*.

Build Container Image Locally

If you have a need to build the shrinkwrap container images on your local system, you can do it as follows:

cd docker
./build.sh local

This will build a set of images called:

• shrinkwraptool/base-slim:local-<ARCH>

• shrinkwraptool/base-slim-nofvp:local-<ARCH>

• shrinkwraptool/base-full:local-<ARCH>

• shrinkwraptool/base-full-nofvp:local-<ARCH>

To use a locally built image, call shrinkwrap as follows if running on an x86_64 system:

shrinkwrap --runtime=<name>-local --image=shrinkwraptool/base-slim:local-x86_64 ...

Or like this if running on an aarch64 system:

shrinkwrap --runtime=<name>-local --image=shrinkwraptool/base-slim:local-aarch64 ...

where <name> is either docker or podman. Note that because the image is not on Docker Hub, the <name>-local runtime is required to prevent Shrinkwrap from erroneously trying to download an update.