cmake: Add cross-toolchain support

- Add host build of protoc
2021-01-07 17:41:08 +01:00
parent 7062089531
commit 91a20cd569
3 changed files with 181 additions and 0 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -231,6 +231,7 @@ check_type_size("int *" SIZEOF_INT_P LANGUAGE CXX)
 message(STATUS "Found int * size: ${SIZEOF_INT_P}")
 cmake_pop_check_state()

+include(host)
 include(deps)
 include(cpp)
 include(flatzinc)
--- a/cmake/host.CMakeLists.txt
+++ b/cmake/host.CMakeLists.txt
@@ -0,0 +1,124 @@
+cmake_minimum_required(VERSION 3.14)
+
+# fetch_git_dependency()
+#
+# CMake function to download, build and install (in staging area) a dependency at configure
+# time.
+#
+# Parameters:
+# NAME: name of the dependency
+# REPOSITORY: git url of the dependency
+# TAG: tag of the dependency
+# PATCH_COMMAND: apply patch
+# SOURCE_SUBDIR: Path to source CMakeLists.txt relative to root dir
+# CMAKE_ARGS: List of specific CMake args to add
+#
+# e.g.:
+# fetch_git_dependency(
+#   NAME
+#     abseil-cpp
+#   URL
+#     https://github.com/abseil/abseil-cpp.git
+#   TAG
+#     master
+#   PATCH_COMMAND
+#     "git apply ${CMAKE_SOURCE_DIR}/patches/abseil-cpp.patch"
+# )
+function(fetch_git_dependency)
+  set(options "")
+  set(oneValueArgs NAME REPOSITORY TAG PATCH_COMMAND SOURCE_SUBDIR)
+  set(multiValueArgs CMAKE_ARGS)
+  cmake_parse_arguments(GIT_DEP
+    "${options}"
+    "${oneValueArgs}"
+    "${multiValueArgs}"
+    ${ARGN}
+  )
+  message(STATUS "Building ${GIT_DEP_NAME}: ...")
+  string(TOLOWER ${GIT_DEP_NAME} NAME_LOWER)
+
+  if(GIT_DEP_PATCH_COMMAND)
+    set(PATCH_CMD "${GIT_DEP_PATCH_COMMAND}")
+  else()
+    set(PATCH_CMD "")
+  endif()
+  configure_file(
+    ${CMAKE_CURRENT_LIST_DIR}/CMakeLists.txt.in
+    ${CMAKE_BINARY_DIR}/_deps/${NAME_LOWER}-subbuild/CMakeLists.txt @ONLY)
+
+  execute_process(
+    COMMAND ${CMAKE_COMMAND} -S. -Bproject_build -G "${CMAKE_GENERATOR}"
+    RESULT_VARIABLE result
+    WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/_deps/${NAME_LOWER}-subbuild)
+  if(result)
+    message(FATAL_ERROR "CMake step for ${GIT_DEP_NAME} failed: ${result}")
+  endif()
+
+  execute_process(
+    COMMAND ${CMAKE_COMMAND} --build project_build --config ${CMAKE_BUILD_TYPE}
+    RESULT_VARIABLE result
+    WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/_deps/${NAME_LOWER}-subbuild)
+  if(result)
+    message(FATAL_ERROR "Build step for ${GIT_DEP_NAME} failed: ${result}")
+  endif()
+
+  if(GIT_DEP_SOURCE_SUBDIR)
+    add_subdirectory(
+      ${CMAKE_BINARY_DIR}/_deps/${NAME_LOWER}-src/${GIT_DEP_SOURCE_SUBDIR}
+      ${CMAKE_BINARY_DIR}/_deps/${NAME_LOWER}-build)
+  else()
+    add_subdirectory(
+      ${CMAKE_BINARY_DIR}/_deps/${NAME_LOWER}-src
+      ${CMAKE_BINARY_DIR}/_deps/${NAME_LOWER}-build)
+  endif()
+
+  message(STATUS "Building ${GIT_DEP_NAME}: ...DONE")
+endfunction()
+
+project(host-meta CXX)
+
+include(FetchContent)
+set(FETCHCONTENT_QUIET OFF)
+set(FETCHCONTENT_UPDATES_DISCONNECTED ON)
+set(BUILD_SHARED_LIBS OFF)
+set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+set(BUILD_TESTING OFF)
+
+message(CHECK_START "Fetching ZLIB")
+list(APPEND CMAKE_MESSAGE_INDENT "  ")
+FetchContent_Declare(
+  zlib
+  GIT_REPOSITORY "https://github.com/madler/ZLIB.git"
+  GIT_TAG "v1.2.11"
+  PATCH_COMMAND git apply "${CMAKE_CURRENT_LIST_DIR}/../../../patches/ZLIB.patch")
+FetchContent_MakeAvailable(zlib)
+list(POP_BACK CMAKE_MESSAGE_INDENT)
+message(CHECK_PASS "fetched")
+
+message(CHECK_START "Fetching Protobuf")
+list(APPEND CMAKE_MESSAGE_INDENT "  ")
+set(protobuf_BUILD_TESTS OFF)
+set(protobuf_BUILD_EXPORT OFF)
+set(protobuf_MSVC_STATIC_RUNTIME OFF)
+
+# FetchContent_Declare(SOURCE_SUBDIR) was introduced in 3.18
+if(${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.18")
+  FetchContent_Declare(
+      protobuf
+      GIT_REPOSITORY "https://github.com/protocolbuffers/protobuf.git"
+      GIT_TAG "v3.14.0"
+      GIT_SUBMODULES ""
+      PATCH_COMMAND git apply "${CMAKE_CURRENT_LIST_DIR}/../../../patches/protobuf-v3.14.0.patch"
+      SOURCE_SUBDIR cmake)
+  FetchContent_MakeAvailable(protobuf)
+else()
+  fetch_git_dependency(
+      NAME Protobuf
+      REPOSITORY "https://github.com/protocolbuffers/protobuf.git"
+      TAG "v3.14.0"
+      PATCH_COMMAND "git apply \"${CMAKE_CURRENT_LIST_DIR}/../../../patches/protobuf-v3.14.0.patch\""
+      SOURCE_SUBDIR cmake)
+endif()
+list(POP_BACK CMAKE_MESSAGE_INDENT)
+message(CHECK_PASS "fetched")
+
--- a/cmake/host.cmake
+++ b/cmake/host.cmake
@@ -0,0 +1,56 @@
+if(NOT CMAKE_CROSSCOMPILING)
+  set(PROTOC_PRG protobuf::protoc)
+  return()
+endif()
+
+message(STATUS "Subproject: HostTools...")
+
+#configure_file(
+#	${CMAKE_CURRENT_SOURCE_DIR}/host.CMakeLists.txt
+#  ${CMAKE_CURRENT_BINARY_DIR}/host_tools/CMakeLists.txt)
+#
+#execute_process(
+#  COMMAND ${CMAKE_COMMAND} -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -G "${CMAKE_GENERATOR}" .
+#  RESULT_VARIABLE result
+#  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/host_tools)
+#if(result)
+#  message(FATAL_ERROR "CMake step for host tools failed: ${result}")
+#endif()
+#execute_process(
+#  COMMAND ${CMAKE_COMMAND} --build .
+#  RESULT_VARIABLE result
+#  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/host_tools)
+#if(result)
+#  message(FATAL_ERROR "Build step for host tools failed: ${result}")
+#endif()
+
+#file(COPY
+#	${CMAKE_CURRENT_SOURCE_DIR}/cmake/host.CMakeLists.txt
+#  DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/host_tools)
+
+configure_file(
+	${CMAKE_CURRENT_SOURCE_DIR}/cmake/host.CMakeLists.txt
+  ${CMAKE_CURRENT_BINARY_DIR}/host_tools/CMakeLists.txt
+  COPYONLY)
+
+add_custom_command(
+  OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/host_tools
+  #COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_SOURCE_DIR}/host.CMakeLists.txt CMakeLists.txt
+  COMMAND ${CMAKE_COMMAND} -E remove_directory build
+  COMMAND ${CMAKE_COMMAND} -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -DCMAKE_RUNTIME_OUTPUT_DIRECTORY:PATH=${CMAKE_CURRENT_BINARY_DIR}/host_tools/bin
+  COMMAND ${CMAKE_COMMAND} --build build --config Release -v
+  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/host_tools
+)
+
+add_custom_target(host_tools
+  DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/host_tools
+  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+
+add_executable(host_protoc IMPORTED GLOBAL)
+set_target_properties(host_protoc PROPERTIES
+  IMPORTED_LOCATION ${CMAKE_CURRENT_BINARY_DIR}/host_tools/bin/protoc)
+
+add_dependencies(host_protoc host_tools)
+set(PROTOC_PRG host_protoc)
+
+message(STATUS "Subproject: HostTools...DONE")