build: create a dedicated CI workflow for forks

Forked bpfilter repositories can't use the project's runner, and the
GitHub-provided runners use an old kernel, preventing unit tests from
being run.

This change disable the project's CI workflows building bpfilter on the
self-hosted runners and add a new workflow, specific to forks, to build
bpfilter and run a few checks.

Signed-off-by: Quentin Deslandes <[email protected]>

.github/workflows/ci.yaml

@@ -14,6 +14,7 @@ permissions:
 
 jobs:
   full:
+    if: github.repository == 'facebook/bpfilter'
     strategy:
       fail-fast: false
       matrix:
@@ -59,6 +60,7 @@ jobs:
         run: make -C $GITHUB_WORKSPACE/build doc
 
   build:
+    if: github.repository == 'facebook/bpfilter'
     strategy:
       fail-fast: false
       matrix:

.github/workflows/fork.yaml

@@ -0,0 +1,51 @@
+name: Fork-specific CI
+
+on:
+  push:
+    branches:
+      - "**"
+
+permissions:
+  checks: write
+  pull-requests: write
+
+jobs:
+  full:
+    if: github.repository != 'facebook/bpfilter'
+    strategy:
+      fail-fast: false
+      matrix:
+        # This forces GitHub to print "fedora:39, x64" in the job name.
+        system: ["fedora:39"]
+        arch: ["X64"]
+        mode: ["release", "debug"]
+    container: "${{ matrix.system }}"
+    runs-on: ["ubuntu-latest"]
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4
+      - name: Install dependencies (Fedora)
+        run: |
+          sudo dnf --disablerepo=* --enablerepo=fedora,updates --setopt=install_weak_deps=False -y install \
+            clang-tools-extra \
+            cmake \
+            libcmocka-devel \
+            doxygen \
+            lcov \
+            libasan \
+            libbpf-devel \
+            libubsan \
+            python3-breathe \
+            python3-furo \
+            python3-sphinx \
+            pkgconf
+      - name: Configure build
+        run: cmake -S $GITHUB_WORKSPACE -B $GITHUB_WORKSPACE/build -DCMAKE_BUILD_TYPE=${{ matrix.mode }}
+      - name: Build
+        run: make -C $GITHUB_WORKSPACE/build
+      # Skip unit tests, the GitHub-hosted runners' kernel is too old.
+      # Skip coverage as unit tests are not run.
+      - name: Check style
+        run: make -C $GITHUB_WORKSPACE/build checkstyle
+      - name: Generate documentation
+        run: make -C $GITHUB_WORKSPACE/build doc

.github/workflows/pages.yaml

@@ -19,6 +19,7 @@ concurrency:
 
 jobs:
   deploy:
+    if: github.repository == 'facebook/bpfilter'
     container: "fedora:39"
     runs-on: ubuntu-latest
     steps: