ci: add workflow with smoke-build with kas #16

	name: Smoke build
	on:
	pull_request:
	branches: ["master", "kirkstone"]

	jobs:
	build:
	strategy:
	matrix:
	kas:
	- kas-poky-snapd.aarch64.yml
	- kas-poky-snapd.x86_64.yml
	# TODO: use large runners when available
	runs-on: [self-hosted, Linux]
	timeout-minutes: 240
	name: ${{ matrix.kas }}
	env:
	# On non-ephemeral workers, downloads and sstate is cached.
	DL_DIR: /srv/meta-snapd/kirkstone/downloads
	SSTATE_DIR: /srv/meta-snapd/kirkstone/sstate-cache
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	- name: Install build dependencies
	run: \|
	sudo apt-get update
	sudo -E DEBIAN_FRONTEND=noninteractive apt install -y kas chrpath diffstat bzip2 cpp g++ gcc lz4 make rpcsvc-proto
	kas --version
	- name: Setup DL_DIR and SSTATE_DIR
	run: \|
	sudo mkdir -p "$DL_DIR"
	sudo mkdir -p "$SSTATE_DIR"
	sudo chown $(id -u).$(id -g) "$DL_DIR" "$SSTATE_DIR"
	# This hack makes DL_DIR and SSTATE_DIR overrides compatible with kas 2.6.3 in Ubuntu 22.04
	mkdir -p build/conf
	printf 'DL_DIR = "%s"\n' "$DL_DIR" >build/conf/auto.conf
	printf 'SSTATE_DIR = "%s"\n' "$SSTATE_DIR" >> build/conf/auto.conf
	- name: Use tmpfs for TMPDIR
	run: \|
	mkdir -p build/tmp
	if [ "$(LANG=C free --total --giga \| awk -e '/Total/ { print $2 }')" -gt 64 ]; then
	sudo mount -o size=64G -t tmpfs none build/tmp
	fi
	- name: Run kas checkout
	run: \|
	kas checkout ${{ matrix.kas }}
	- name: Run kas build
	run: \|
	kas build ${{ matrix.kas }} --target snapd-demo-image
	- name: Unmount tmpfs
	if: always()
	run: \|
	# Lazy umount as apparently something may be using this still?
	sudo umount -l build/tmp \|\| true

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