images: Add clang-format image

This commit adds a clang-format image that can be used to format C code.
The image is made to be as minimal as possible, just a statically
compiled clang-format binary in a scratch container. This makes it
quick to pull and allows for the extraction of the binary to run on
a host system.

Signed-off-by: Dylan Reimerink <[email protected]>

Author: dylandreimerink

Diff for: .github/workflows/images.yaml

@@ -82,6 +82,16 @@ jobs:
         with:
           entrypoint: make
           args: llvm-image PUSH=${{ steps.vars.outputs.push }}
+      - uses: docker://quay.io/cilium/image-maker:e55375ca5ccaea76dc15a0666d4f57ccd9ab89de
+        name: Run make clang-format-image
+        env:
+          DOCKER_HUB_PASSWORD: ${{ secrets.DOCKER_HUB_PASSWORD_CI }}
+          DOCKER_HUB_USERNAME: ${{ secrets.DOCKER_HUB_USERNAME_CI }}
+          QUAY_PASSWORD: ${{ secrets.QUAY_PASSWORD_IMAGE_TOOLS }}
+          QUAY_USERNAME: ${{ secrets.QUAY_USERNAME_IMAGE_TOOLS }}
+        with:
+          entrypoint: make
+          args: clang-format-image PUSH=${{ steps.vars.outputs.push }}
       - uses: docker://quay.io/cilium/image-maker:e55375ca5ccaea76dc15a0666d4f57ccd9ab89de
         name: Run make startup-script-image
         env:

Diff for: Makefile

@@ -7,7 +7,7 @@ PUSH ?= false
 EXPORT ?= false
 PLATFORMS ?= linux/amd64,linux/arm64
 
-all-images: lint maker-image tester-image compilers-image bpftool-image llvm-image network-perf-image ca-certificates-image startup-script-image checkpatch-image iptables-image
+all-images: lint maker-image tester-image compilers-image bpftool-image llvm-image clang-format-image network-perf-image ca-certificates-image startup-script-image checkpatch-image iptables-image
 
 
 lint:
@@ -31,6 +31,9 @@ bpftool-image: .buildx_builder
 llvm-image: .buildx_builder
 	PUSH=$(PUSH) EXPORT=$(EXPORT) TEST=true scripts/build-image.sh cilium-llvm images/llvm $(PLATFORMS) "$$(cat .buildx_builder)" $(REGISTRIES)
 
+clang-format-image: .buildx_builder
+	PUSH=$(PUSH) EXPORT=$(EXPORT) scripts/build-image.sh cilium-clang-format images/clang-format $(PLATFORMS) "$$(cat .buildx_builder)" $(REGISTRIES)
+
 ca-certificates-image: .buildx_builder
 	PUSH=$(PUSH) EXPORT=$(EXPORT) scripts/build-image.sh ca-certificates images/ca-certificates $(PLATFORMS) "$$(cat .buildx_builder)" $(REGISTRIES)
 

Diff for: images/clang-format/Dockerfile

@@ -0,0 +1,21 @@
+# Copyright 2024 Authors of Cilium
+# SPDX-License-Identifier: Apache-2.0
+
+ARG COMPILERS_IMAGE=quay.io/cilium/image-compilers:5569a29cea6b3ad50aeb03102aaf3dc03841197c@sha256:b15dbedb7c49816c74a765e2f6ecdb9359763b8e4e4328d794f48b9cefae9804
+
+FROM --platform=linux/amd64 ${COMPILERS_IMAGE} as builder
+
+COPY checkout-llvm.sh /tmp/checkout-llvm.sh
+RUN /tmp/checkout-llvm.sh
+
+COPY build-llvm-native.sh /tmp/build-llvm-native.sh
+RUN /tmp/build-llvm-native.sh
+
+COPY build-llvm-cross-aarch64.sh /tmp/build-llvm-cross-aarch64.sh
+RUN /tmp/build-llvm-cross-aarch64.sh
+
+FROM scratch
+LABEL maintainer="[email protected]"
+
+ARG TARGETPLATFORM
+COPY --from=builder /out/${TARGETPLATFORM}/bin /

Diff for: images/clang-format/build-llvm-cross-aarch64.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+
+# Copyright 2017-2024 Authors of Cilium
+# SPDX-License-Identifier: Apache-2.0
+
+set -o xtrace
+set -o errexit
+set -o pipefail
+set -o nounset
+
+triplet="aarch64-linux-gnu"
+
+mkdir -p /src/llvm/llvm/build-cross-aarch64
+
+cd /src/llvm/llvm/build-cross-aarch64
+
+CC="${triplet}-gcc" CXX="${triplet}-g++" \
+  cmake .. -G "Ninja" \
+    -DLLVM_TARGETS_TO_BUILD="BPF" \
+    -DLLVM_ENABLE_PROJECTS="clang" \
+    -DBUILD_SHARED_LIBS="OFF" \
+    -DLLVM_BUILD_STATIC="ON" \
+    -DCMAKE_CXX_FLAGS="-s -flto" \
+    -DCMAKE_BUILD_TYPE="Release" \
+    -DLLVM_BUILD_RUNTIME="OFF" \
+    -DLLVM_TABLEGEN="/src/llvm/llvm/build-native/bin/llvm-tblgen" \
+    -DCLANG_TABLEGEN="/src/llvm/llvm/build-native/bin/clang-tblgen" \
+    -DCMAKE_CROSSCOMPILING="True" \
+    -DCMAKE_INSTALL_PREFIX="/usr/local"
+
+ninja clang-format
+
+${triplet}-strip bin/clang-format
+
+mkdir -p /out/linux/arm64/bin
+cp bin/clang-format /out/linux/arm64/bin

Diff for: images/clang-format/build-llvm-native.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+# Copyright 2017-2024 Authors of Cilium
+# SPDX-License-Identifier: Apache-2.0
+
+set -o xtrace
+set -o errexit
+set -o pipefail
+set -o nounset
+
+mkdir -p /src/llvm/llvm/build-native
+
+cd /src/llvm/llvm/build-native
+
+cmake .. -G "Ninja" \
+  -DLLVM_TARGETS_TO_BUILD="BPF" \
+  -DLLVM_ENABLE_PROJECTS="clang" \
+  -DBUILD_SHARED_LIBS="OFF" \
+  -DLLVM_BUILD_STATIC="ON" \
+  -DCMAKE_CXX_FLAGS="-s -flto" \
+  -DCMAKE_BUILD_TYPE="Release" \
+  -DLLVM_BUILD_RUNTIME="OFF" \
+  -DCMAKE_INSTALL_PREFIX="/usr/local"
+
+# llvm-tblgen and clang-tblgen are needed to build the aarch64 version of clang-format
+ninja clang-format llvm-tblgen clang-tblgen
+
+strip bin/clang-format
+
+mkdir -p /out/linux/amd64/bin
+cp bin/clang-format /out/linux/amd64/bin

Diff for: images/clang-format/checkout-llvm.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+# Copyright 2017-2024 Authors of Cilium
+# SPDX-License-Identifier: Apache-2.0
+
+set -o xtrace
+set -o errexit
+set -o pipefail
+set -o nounset
+
+rev="llvmorg-17.0.6"
+
+git config --global user.email "[email protected]"
+git config --global user.name  "Cilium Maintainers"
+
+git clone --branch "${rev}" https://github.com/llvm/llvm-project.git /src/llvm