CI for license check (#78)

* license check CI

* fix ci

* check both headers and source

* add SPDX identifiers

* trigger on only master

.github/workflows/license.yml

@@ -0,0 +1,21 @@
+name: license
+
+on:
+  push:
+    branches: [ master ]
+    paths-ignore: '**.md'
+  pull_request:
+    branches: [ master ]
+    paths-ignore: '**.md'
+
+jobs:
+  license_check:
+    name: License check
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Check license
+        run: |
+          find include/small_gicp src/small_gicp -type f | xargs -I filename bash -c 'if ! grep -q SPDX-License-Identifier filename; then echo filename : lisence not found; exit 1; fi'

include/small_gicp/ann/flat_container.hpp

@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: Copyright 2024 Kenji Koide
+// SPDX-License-Identifier: MIT
 #pragma once
 
 #include <queue>

include/small_gicp/ann/knn_result.hpp

@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: Copyright 2024 Kenji Koide
+// SPDX-License-Identifier: MIT
 #pragma once
 
 #include <array>

include/small_gicp/factors/robust_kernel.hpp

@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: Copyright 2024 Kenji Koide
+// SPDX-License-Identifier: MIT
 #pragma once
 
 #include <Eigen/Core>