[Buildroot] Guidance creating first package (WAMR)

[Jonathan Beri]

Hello! I'm new to buildroot and so far have found the project to be very
mature. My goal is to create an environment for WebAssembly Micro Runtime
(WAMR,) a standalone WebAssembly (Wasm) runtime on SBCs like the Raspberry
Pi. See https://github.com/intel/wasm-micro-runtime.

I started by using a docker container to build an image using the Raspberry
Pi defconfig. I got it working in an afternoon. Next I created a `wamr`
folder in `packages`, added a `Config.in` and started to work on a `wamr.mk
`.

And here's where I need help. The build process for WAMR Core is fairly
straightforward - see
https://github.com/intel/wasm-micro-runtime/blob/master/doc/building.md#build-wamr-core.
I contributed the Dockerfile, which took a few hours to write. I'm
comfortable on linux but far from an expert. However, I'm little more than
a novice when it comes kconfig, make and the like.

I tried following the CMake docs to build a package:
https://buildroot.org/downloads/manual/manual.html#_infrastructure_for_cmake_based_packages.
Here's an example of what I tried:

```
################################################################################
#
# wamr
#
################################################################################

WAMR_VERSION = a522e985f30c12c9c66eda6ff3ab41f493b31b2c
WAMR_SOURCE = wasm-micro-runtime-master.tar.gz
WAMR_SITE = $(call github,intel,wasm-micro-runtime,$(WAMR_VERSION))

$(eval $(cmake-package))
```

>From here I didn't know how to test even that this syntax is correct. I've
tried `./utils/test-pkg`, `make wamr-source` & `make wamr-build` but the
outputs haven't been helpful.

I've tried looking for additional tutorials on the web (Bootlin has some
lovely detailed ones) but so far none that have helped me wrap my head
around the packaging system.

Anyone have suggestions or pointers?

Many thanks!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.busybox.net/pipermail/buildroot/attachments/20190910/1341ef68/attachment.html>