Add CI and improve build system (#293)

## Link to GitHub Issue, if one exists
Fixes #292

## Description of change
This PR adds CI with Github Actions. Runs on every push and pull
request. If a new commit is pushed, any previous runs are cancelled for
that branch.

In total, these optimisations (on a 7800X3D with 32GB 6000MT/s RAM and
an NVMe Gen4 SSD):
* Reduces `spicetools/deps` image size by around 200 MB, and build time
by almost 50%
* Reduces compilation time by around 9%

Changes:
* Pull archlinux image from GHCR so that we don't run into pull limits
from docker.io
* Use `base-devel` archlinux image
* Reduces image build time from 141 seconds to 109 seconds on my machine
  * Clean up unneeded packages
* Small reduction in `spicetools/deps` image size (4.35 GB vs 4.14 GB)
* Use precompiled `yay` binary
* Reduces image build time from 163 seconds to 141 seconds on my machine
* Use `nproc` to get the number of cores instead of parsing
`/proc/cpuinfo` with `awk`
* Use `ninja` to compile
  * Speeds up compile times a little, around 13 seconds on my machine
* Don't run `docker run` in interactive TTY in `build_docker.sh`
  * Github Actions disallows interactive TTYs
  * Still allowed for the batch script
* `time` the compilation process
* Enable BuildKit in the bash script
  * Required for build contexts
* Don't use `USER` instruction
  * Breaks Github Actions, doesn't seem to affect build?
* More info:
https://docs.github.com/en/actions/sharing-automations/creating-actions/dockerfile-support-for-github-actions#user
  * `USER` also seems to cause issues on a mounted ReFS image
* Add executable bits to bash scripts

Future ideas:
* Combine `external/Dockerfile` and `./Dockerfile` into one to
deduplicate images and save disk space
* Fix the weird `/src/src` directory structure in the Dockerfile and
build scripts
* Investigate CMake and ninja optimisations?

## Compiling
Check CI status on my fork.

## Testing
Tested with docker on Windows. Also play tested a bit to make sure the
Github Actions artifact works.

.github/workflows/ci.yml

@@ -0,0 +1,22 @@
+on: [push, pull_request]
+name: Continuous Integration
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  fw-ci:
+    name: Build
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ./src/spice2x
+    steps:
+      - uses: actions/checkout@v4
+      - name: Compile
+        run: ./build_docker.sh
+      - uses: actions/upload-artifact@v4
+        with:
+          name: spice2x
+          path: src/spice2x/bin
+          if-no-files-found: error

src/spice2x/Dockerfile

@@ -1,8 +1,7 @@
 FROM spicetools/deps
 WORKDIR /src
-RUN chown user:user /src
+
-USER user
+COPY --from=gitroot . /src/.git
-COPY --chown=user:user --from=gitroot . /src/.git
+COPY . /src/src/spice2x
-COPY --chown=user:user . /src/src/spice2x
 WORKDIR /src/src/spice2x
 CMD ["./build_all.sh"]

src/spice2x/build_all.sh

@@ -57,7 +57,7 @@ then
 fi
 
 # determine number of cores
-CORES=$(awk '/^processor\t/ {cores[$NF]++} END {print length(cores)}' /proc/cpuinfo)
+CORES=$(nproc)
 
 # print information
 echo ""
@@ -74,6 +74,7 @@ echo "Build Type: $BUILD_TYPE"
 echo "Cores: $CORES"
 echo ""
 
+time (
 	# 32 bit
 	echo "Building 32bit targets..."
 	echo "========================="
@@ -83,7 +84,7 @@ then
 	fi
 	mkdir -p ${BUILDDIR_32}
 	pushd ${BUILDDIR_32} > /dev/null
-cmake -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_32} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} $OLDPWD && make -j ${CORES} ${TARGETS_32}
+	cmake -G "Ninja" -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_32} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} $OLDPWD && ninja ${TARGETS_32}
 	popd > /dev/null
 
 	# 64 bit
@@ -96,12 +97,13 @@ then
 	fi
 	mkdir -p ${BUILDDIR_64}
 	pushd ${BUILDDIR_64} > /dev/null
-cmake -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_64} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} $OLDPWD && make -j ${CORES} ${TARGETS_64}
+	cmake -G "Ninja" -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_64} -DCMAKE_BUILD_TYPE=${BUILD_TYPE} $OLDPWD && ninja ${TARGETS_64}
 	popd > /dev/null
 
 	echo ""
 	echo "Compilation process done :)"
 	echo "==========================="
+)
 
 # generate PDBs
 if false  # ((DEBUG > 0))

src/spice2x/build_docker.sh

@@ -1,6 +1,4 @@
 #!/bin/bash
-export DOCKER_BUILDKIT=0
-
 docker build --pull $PWD/external/docker -t spicetools/deps --platform linux/x86_64
 docker build --build-context gitroot=$PWD/../../.git . -t spicetools/spice:latest --no-cache
-docker run --rm -it -v $PWD/dist:/src/src/spice2x/dist -v $PWD/bin:/src/src/spice2x/bin spicetools/spice
+docker run --rm -v $PWD/dist:/src/src/spice2x/dist -v $PWD/bin:/src/src/spice2x/bin spicetools/spice

src/spice2x/external/docker/Dockerfile

@@ -1,20 +1,11 @@
-FROM archlinux:base
+FROM ghcr.io/archlinux/archlinux:base-devel
 
-RUN pacman --noconfirm -Syu gettext \
+RUN pacman --noconfirm -Syu git \
-    base-devel \
-    git \
     bash \
     zip \
     upx \
-    sudo \
+    ninja \
-    binutils \
-    file \
-    make \
-    gcc \
-    fakeroot \
-    diffutils \
     cmake \
-    awk \
     unzip \
     mingw-w64-crt \
     mingw-w64-winpthreads \
@@ -22,4 +13,4 @@ RUN pacman --noconfirm -Syu gettext \
     mingw-w64-headers \
     mingw-w64-binutils
 RUN useradd user -m && echo "ALL ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
-RUN su user -c "cd /tmp/ && git clone https://aur.archlinux.org/yay.git --depth=1 && cd yay && makepkg --noconfirm -si && yay --noconfirm -S mingw-w64-cmake"
+RUN su user -c "cd /tmp/ && git clone https://aur.archlinux.org/yay-bin.git --depth=1 && cd yay-bin && makepkg --noconfirm -si && yay --noconfirm -S mingw-w64-cmake"