Migrate from protobuild to buf

Like containerd did recently, we can migrate from protobuild to buf.

containerd/containerd#12762

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: kzys

.github/workflows/ci.yml

@@ -193,23 +193,14 @@ jobs:
           go-version: '1.22.x'
           cache-dependency-path: src/github.com/containerd/cgroups
 
-      - name: Set env
-        shell: bash
-        run: |
-          echo "GOPATH=${{ github.workspace }}" >> $GITHUB_ENV
-          echo "${{ github.workspace }}/bin" >> $GITHUB_PATH
+      - name: Install buf
+        uses: bufbuild/buf-setup-action@v1
 
-      - name: Install protoc
-        run: |
-          curl -LO https://github.com/protocolbuffers/protobuf/releases/download/v21.5/protoc-21.5-linux-x86_64.zip
-          # /usr/local is not writable from GitHub Actions' user
-          sudo unzip protoc-21.5-linux-x86_64.zip -d /usr/local
+      - name: Install protoc-gen-go
+        run: go install google.golang.org/protobuf/cmd/protoc-gen-go@v1.28
 
-      - name: Install proto-related tools for Go
-        run: |
-          go install google.golang.org/protobuf/cmd/protoc-gen-go@v1.28
-          go install github.com/containerd/protobuild@v0.3.0
-          go install github.com/containerd/protobuild/cmd/go-fix-acronym@v0.3.0
+      - name: Install go-fix-acronym
+        run: go install github.com/containerd/protobuild/cmd/go-fix-acronym@v0.3.0
 
       - name: Compare auto-generated Go files
         run: |

Makefile

@@ -24,6 +24,6 @@ cgutil:
 	cd cmd/cgctl && $(GO) build $(GO_BUILD_FLAGS) -v $(GO_TAGS)
 
 proto:
-	protobuild --quiet ${PACKAGES}
+	buf generate
 	# Keep them Go-idiomatic and backward-compatible with the gogo/protobuf era.
 	go-fix-acronym -w -a '(Cpu|Tcp|Rss|Psi)' $(shell find cgroup1/stats/ cgroup2/stats/ -name '*.pb.go')

Protobuild.toml

@@ -0,0 +1,5 @@
+version: v2
+plugins:
+  - local: protoc-gen-go
+    out: .
+    opt: paths=source_relative

buf.gen.yaml

@@ -0,0 +1 @@
+version: v2