Fix Docker builds and add ARM support

.github/workflows/main.yml

@@ -7,7 +7,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ARCH: [x86_64, i386]
+        ARCH: [x86_64, i686, aarch64, armhf]
 
     name: AppImage ${{ matrix.ARCH }}
     runs-on: ubuntu-latest
@@ -18,6 +18,8 @@ jobs:
       - uses: actions/checkout@v4
         with:
           submodules: recursive
+      - name: Set up QEMU integration for Docker
+        run: docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
       - name: Build AppImage in Docker
         run: bash -ex ci/build-in-docker.sh
       - name: Archive artifacts

ci/Dockerfile

@@ -0,0 +1,49 @@
+# current Debian oldstable as of Dec 2023
+# we use Debian because they still provide i386 builds
+# (also, they ship Qt 5.15.2, so we no longer have to rely on third-party builds)
+# and it provides a C++17 compatible compiler out of the box!
+FROM debian:bullseye
+
+ARG ARCH
+ARG DOCKER_ARCH
+ARG CMAKE_ARCH
+ENV ARCH=${ARCH} DOCKER_ARCH=${DOCKER_ARCH} CMAKE_ARCH=${CMAKE_ARCH}
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update && \
+    apt-get install -y qtbase5-dev qttools5-dev-tools qtwayland5-dev-tools qtwayland5-private-dev \
+        libgl1 libdrm-dev mesa-common-dev \
+        build-essential libssl-dev autoconf automake libtool \
+        wget vim-common desktop-file-utils pkgconf libgpgme-dev \
+        libglib2.0-dev libcairo2-dev librsvg2-dev libfuse-dev git libcurl4-openssl-dev argagg-dev libgcrypt20-dev libboost-dev \
+        liblzma-dev libzstd-dev zlib1g-dev libarchive-dev
+
+RUN wget -qO- https://artifacts.assassinate-you.net/prebuilt-cmake/cmake-v3.28.0-debian-bullseye-"${CMAKE_ARCH}".tar.gz | \
+    tar xzv -C/usr --strip-components=1
+
+COPY ./install-gtest.sh /
+RUN bash /install-gtest.sh
+
+COPY pkgconfig/*.pc /
+RUN mv /*.pc /usr/lib/*-linux-gnu*/pkgconfig/
+
+ENV APPIMAGE_EXTRACT_AND_RUN=1
+
+ENV DOCKER=1
+
+#RUN git clone https://github.com/nlohmann/json.git -b v3.11.2 --depth=1 && \
+#    cd json && \
+#    mkdir build && \
+#    cd build && \
+#    cmake .. -DCMAKE_INSTALL_PREFIX=/usr/local && \
+#    make -j "$(nproc --ignore=1)" install && \
+#    cd ../.. && \
+#    rm -rf json/
+
+RUN apt-get update && apt-get install -y nlohmann-json3-dev
+
+# work around bug in FindCURL.cmake, which does not parse the pkg-config provided protocols and features into lists causing
+# the comparison in the loop to yield false negative results
+# this makes it use curl-config which works much better
+RUN rm /usr/lib/*-linux-gnu*/pkgconfig/libcurl.pc

ci/build-in-docker.sh

@@ -1,35 +1,67 @@
 #! /bin/bash
 
-if [[ "$DIST" == "" ]] || [[ "$ARCH" == "" ]]; then
-    echo "Usage: env ARCH=... DIST=... bash $0"
+if [[ "$ARCH" == "" ]]; then
+    echo "Usage: env ARCH=... bash $0"
     exit 1
 fi
 
-set -e
-set -x
+set -euxo pipefail
+
+case "$ARCH" in
+    x86_64)
+        docker_platform=linux/amd64
+        ;;
+    i686)
+        CMAKE_ARCH=i386
+        docker_platform=linux/386
+        ;;
+    armhf)
+        docker_platform=linux/arm/v7
+        ;;
+    aarch64)
+        docker_platform=linux/arm64/v8
+        ;;
+    *)
+        echo "Unsupported architecture: $ARCH"
+        exit 2
+esac
+
+CMAKE_ARCH="${CMAKE_ARCH:-"$ARCH"}"
 
 cwd="$PWD"
 repo_root="$(readlink -f "$(dirname "$0")"/..)"
 
 # needed to keep user ID in and outside Docker in sync to be able to write to workspace directory
-image=appimageupdate-build:"$DIST"-"$ARCH"
-dockerfile=Dockerfile."$ARCH"
-
-if [ ! -f "$repo_root"/ci/"$dockerfile" ]; then
-    echo "Error: $dockerfile could not be found"
-    exit 1
-fi
+image=appimageupdate-build
 
 # building local image to "cache" installed dependencies for subsequent builds
-docker build -t "$image" -f "$repo_root"/ci/"$dockerfile" --build-arg DIST="$DIST" "$repo_root"/ci
+docker build \
+    --platform "$docker_platform" \
+    -t "$image" \
+    --build-arg ARCH="$ARCH" \
+    --build-arg CMAKE_ARCH="$CMAKE_ARCH" \
+    "$repo_root"/ci
 
 # run the build with the current user to
 #   a) make sure root is not required for builds
 #   b) allow the build scripts to "mv" the binaries into the /out directory
 uid="$(id -u)"
+
+tty_args=()
+if [ -t 0 ]; then tty_args+=("-t"); fi
+
 # mount workspace read-only, trying to make sure the build doesn't ever touch the source code files
 # of course, this only works reliably if you don't run this script from that directory
 # but it's still not the worst idea to do so
-docker run --platform "$ARCH" \
-    --user "$uid" --rm -i -e ARCH -e GITHUB_RUN_NUMBER -e CI=1 -v "$repo_root":/ws:ro -v "$cwd":/out "$image" \
-    bash -xec 'cd /out && bash -xe /ws/ci/build-appimages.sh'
+docker run \
+    --rm \
+    -i \
+    "${tty_args[@]}" \
+    -e CI=1 \
+    -e GITHUB_RUN_NUMBER \
+    -v "$repo_root":/ws:ro \
+    -v "$cwd":/out \
+    -w /out \
+    --user "$uid" \
+    "$image" \
+    bash /ws/ci/build-appimages.sh