infra/cmake/packages/FlatBuffersConfig.cmake

   1 function(_FlatBuffers_import)
   2   find_package(Flatbuffers QUIET)
   3   set(FlatBuffers_FOUND ${Flatbuffers_FOUND} PARENT_SCOPE)
   4 endfunction(_FlatBuffers_import)
   5
   6 function(_FlatBuffers_build)
   7   if(NOT BUILD_FLATBUFFERS)
   8     return()
   9   endif(NOT BUILD_FLATBUFFERS)
  10
  11   nnas_find_package(FlatBuffersSource EXACT 1.10 QUIET)
  12
  13   if(NOT FlatBuffersSource_FOUND)
  14     # Source is not available
  15     return()
  16   endif(NOT FlatBuffersSource_FOUND)
  17
  18   set(ADDITIONAL_CXX_FLAGS "")
  19   if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 8.0)
  20     set(ADDITIONAL_CXX_FLAGS "-Wno-error=class-memaccess")
  21   endif()
  22
  23   nnas_include(ExternalBuildTools)
  24   ExternalBuild_CMake(CMAKE_DIR   ${FlatBuffersSource_DIR}
  25                       BUILD_DIR   ${CMAKE_BINARY_DIR}/externals/FLATBUFFERS/build
  26                       INSTALL_DIR ${EXT_OVERLAY_DIR}
  27                       BUILD_FLAGS ${ADDITIONAL_CXX_FLAGS}
  28                       IDENTIFIER  "1.10-fix2"
  29                       EXTRA_OPTS "-DFLATBUFFERS_BUILD_TESTS:BOOL=OFF"
  30                       PKG_NAME    "FLATBUFFERS")
  31
  32 endfunction(_FlatBuffers_build)
  33
  34 _FlatBuffers_build()
  35 _FlatBuffers_import()
  36
  37 if(FlatBuffers_FOUND)
  38   if(NOT TARGET flatbuffers)
  39     add_library(flatbuffers INTERFACE)
  40     target_link_libraries(flatbuffers INTERFACE flatbuffers::flatbuffers)
  41     message(STATUS "Found FlatBuffers: TRUE")
  42   endif(NOT TARGET flatbuffers)
  43
  44   function(FlatBuffers_Generate PREFIX OUTPUT_DIR SCHEMA_DIR)
  45     get_filename_component(abs_output_dir ${OUTPUT_DIR} ABSOLUTE)
  46     get_filename_component(abs_schema_dir ${SCHEMA_DIR} ABSOLUTE)
  47
  48     foreach(schema ${ARGN})
  49       get_filename_component(schema_fn "${schema}" NAME)
  50       get_filename_component(dir "${schema}" DIRECTORY)
  51
  52       get_filename_component(schema_fn_we "${schema_fn}" NAME_WE)
  53
  54       list(APPEND SCHEMA_FILES "${abs_schema_dir}/${schema}")
  55       list(APPEND OUTPUT_FILES "${abs_output_dir}/${schema_fn_we}_generated.h")
  56     endforeach()
  57
  58     add_custom_command(OUTPUT ${OUTPUT_FILES}
  59                        COMMAND ${CMAKE_COMMAND} -E make_directory "${abs_output_dir}"
  60                        COMMAND "$<TARGET_FILE:flatbuffers::flatc>" -c --no-includes
  61                        --no-union-value-namespacing
  62                        --gen-object-api -o "${abs_output_dir}"
  63                        ${SCHEMA_FILES}
  64                        DEPENDS flatbuffers::flatc)
  65
  66     set(${PREFIX}_SOURCES ${OUTPUT_FILES} PARENT_SCOPE)
  67     set(${PREFIX}_INCLUDE_DIRS ${abs_output_dir} PARENT_SCOPE)
  68   endfunction(FlatBuffers_Generate)
  69
  70   function(FlatBuffers_Target TGT)
  71     set(oneValueArgs OUTPUT_DIR SCHEMA_DIR INCLUDE_DIR)
  72     set(multiValueArgs SCHEMA_FILES)
  73     cmake_parse_arguments(ARG "" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
  74
  75     # Use OUTPUT_DIR as INCLUDE_DIR if INCLUDE_DIR is not specified
  76     if(NOT ARG_INCLUDE_DIR)
  77       set(ARG_INCLUDE_DIR ${ARG_OUTPUT_DIR})
  78     endif(NOT ARG_INCLUDE_DIR)
  79
  80     get_filename_component(abs_output_dir ${ARG_OUTPUT_DIR} ABSOLUTE)
  81     get_filename_component(abs_include_dir ${ARG_INCLUDE_DIR} ABSOLUTE)
  82     get_filename_component(abs_schema_dir ${ARG_SCHEMA_DIR} ABSOLUTE)
  83
  84     # Let's reset list variables before using them
  85     # NOTE THIS DOES NOT AFFECT parent scope
  86     unset(SCHEMA_FILES)
  87     unset(OUTPUT_FILES)
  88
  89     foreach(schema ${ARG_SCHEMA_FILES})
  90       get_filename_component(schema_fn "${schema}" NAME)
  91       get_filename_component(dir "${schema}" DIRECTORY)
  92
  93       get_filename_component(schema_fn_we "${schema_fn}" NAME_WE)
  94
  95       list(APPEND SCHEMA_FILES "${abs_schema_dir}/${schema}")
  96       list(APPEND OUTPUT_FILES "${abs_output_dir}/${schema_fn_we}_generated.h")
  97     endforeach()
  98
  99     # Generate headers
 100     add_custom_command(OUTPUT ${OUTPUT_FILES}
 101                        COMMAND ${CMAKE_COMMAND} -E make_directory "${abs_output_dir}"
 102                        COMMAND "$<TARGET_FILE:flatbuffers::flatc>" -c --no-includes
 103                                --no-union-value-namespacing
 104                                --gen-object-api -o "${abs_output_dir}"
 105                                ${SCHEMA_FILES}
 106                        DEPENDS ${SCHEMA_FILES}
 107                        COMMENT "Generate '${TGT}' headers")
 108
 109     # NOTE This header-only library is deliberately declared as STATIC library
 110     #      to avoid possible scope issues related with generated files
 111     add_library(${TGT} STATIC ${OUTPUT_FILES})
 112     set_target_properties(${TGT} PROPERTIES LINKER_LANGUAGE CXX)
 113     target_include_directories(${TGT} PUBLIC "${ARG_INCLUDE_DIR}")
 114     target_link_libraries(${TGT} PUBLIC flatbuffers)
 115   endfunction(FlatBuffers_Target)
 116 endif(FlatBuffers_FOUND)