Add CMake install commands for Au

.github/license-check/license-config.json

@@ -18,7 +18,8 @@
       ".github/**/*.yml",
       "requirements.in",
       "cmake/*.cmake",
-      "WORKSPACE"
+      "cmake/*.cmake.in",
+      "**/WORKSPACE"
     ],
     "exclude": [
       "third_party/**/*"

CMakeLists.txt

@@ -32,6 +32,9 @@ project(
    LANGUAGES CXX
 )
 
+# The export set for all of our headers.
+set(AU_EXPORT_SET_NAME AuHeaders)
+
 enable_testing()
 
 # Bring in GoogleTest so we can build and run the tests.
@@ -52,4 +55,36 @@ set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
 FetchContent_MakeAvailable(googletest)
 include(GoogleTest)
 
-add_subdirectory(au)
+add_subdirectory(cmake/project_symlinks)
+
+# Configure how Au will be installed.
+#
+# (This is necessary for it to be usable in other CMake projects.)
+
+set(AU_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/Au)
+
+install(
+   EXPORT ${AU_EXPORT_SET_NAME}
+   DESTINATION ${AU_CMAKE_DIR}
+   NAMESPACE Au::
+   FILE AuHeaders.cmake
+)
+
+include(CMakePackageConfigHelpers)
+configure_package_config_file(
+   ${CMAKE_CURRENT_SOURCE_DIR}/cmake/AuConfig.cmake.in
+   AuConfig.cmake
+   INSTALL_DESTINATION ${AU_CMAKE_DIR}
+)
+
+write_basic_package_version_file(
+   AuConfigVersion.cmake
+   COMPATIBILITY SameMinorVersion
+)
+
+install(
+   FILES
+      ${CMAKE_CURRENT_BINARY_DIR}/AuConfig.cmake
+      ${CMAKE_CURRENT_BINARY_DIR}/AuConfigVersion.cmake
+   DESTINATION ${AU_CMAKE_DIR}
+)

WORKSPACE

@@ -216,3 +216,11 @@ http_archive(
 
 # END SECTION: Install buildifier.
 ################################################################################
+
+# This is not a "real" local bazel repository.  We define this in this WORKSPACE
+# file because it will prevent bazel from looking for packages in this folder
+# and its children.
+local_repository(
+    name = "ignore_cmake",
+    path = "./cmake",
+)

au/CMakeLists.txt

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-include(../cmake/HeaderOnlyLibrary.cmake)
+include("${PROJECT_SOURCE_DIR}/cmake/HeaderOnlyLibrary.cmake")
 
 #
 # Publicly exported targets

cmake/AuConfig.cmake.in

@@ -0,0 +1,19 @@
+# Copyright 2024 Aurora Operations, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+@PACKAGE_INIT@
+
+include(${CMAKE_CURRENT_LIST_DIR}/AuHeaders.cmake)
+
+check_required_components(Au)

cmake/HeaderOnlyLibrary.cmake

@@ -45,7 +45,7 @@ function(header_only_library)
     ${ARG_NAME}
     INTERFACE
     FILE_SET HEADERS
-    BASE_DIRS ${CMAKE_SOURCE_DIR}
+    BASE_DIRS "${PROJECT_SOURCE_DIR}/cmake/project_symlinks"
     FILES ${ARG_HEADERS}
   )
   if (DEFINED ARG_DEPS)
@@ -61,8 +61,19 @@ function(header_only_library)
   # See: https://stackoverflow.com/a/68321274
   if (ARG_INTERNAL_ONLY)
     set_target_properties(${ARG_NAME} PROPERTIES EXPORT_NAME "_Au_private_${ARG_NAME}")
+  else()
+    add_library(Au::${ARG_NAME} ALIAS ${ARG_NAME})
   endif()
 
+  # Install the library.  (This is required for other projects to use Au via CMake.)
+  include(GNUInstallDirs)
+  install(
+    TARGETS ${ARG_NAME}
+    EXPORT ${AU_EXPORT_SET_NAME}
+    FILE_SET HEADERS
+    INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
+  )
+
   # Add the test, if requested.
   if (DEFINED ARG_GTEST_SRCS)
     add_executable("${ARG_NAME}_test")

cmake/WORKSPACE

@@ -0,0 +1,15 @@
+# Copyright 2024 Aurora Operations, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This file exists so that bazel will ignore this folder.

cmake/project_symlinks/CMakeLists.txt

@@ -0,0 +1,15 @@
+# Copyright 2024 Aurora Operations, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+add_subdirectory(au)

cmake/project_symlinks/au

@@ -0,0 +1 @@
+../../au