1# Copyright 2015 Google Inc. All rights reserved. 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# http://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12# See the License for the specific language governing permissions and 13# limitations under the License. 14 15# General function to create FlatBuffer build rules for the given list of 16# schemas. 17# 18# flatbuffers_schemas: A list of flatbuffer schema files to process. 19# 20# schema_include_dirs: A list of schema file include directories, which will be 21# passed to flatc via the -I parameter. 22# 23# custom_target_name: The generated files will be added as dependencies for a 24# new custom target with this name. You should add that target as a dependency 25# for your main target to ensure these files are built. You can also retrieve 26# various properties from this target, such as GENERATED_INCLUDES_DIR, 27# BINARY_SCHEMAS_DIR, and COPY_TEXT_SCHEMAS_DIR. 28# 29# additional_dependencies: A list of additional dependencies that you'd like 30# all generated files to depend on. Pass in a blank string if you have none. 31# 32# generated_includes_dir: Where to generate the C++ header files for these 33# schemas. The generated includes directory will automatically be added to 34# CMake's include directories, and will be where generated header files are 35# placed. This parameter is optional; pass in empty string if you don't want to 36# generate include files for these schemas. 37# 38# binary_schemas_dir: If you specify an optional binary schema directory, binary 39# schemas will be generated for these schemas as well, and placed into the given 40# directory. 41# 42# copy_text_schemas_dir: If you want all text schemas (including schemas from 43# all schema include directories) copied into a directory (for example, if you 44# need them within your project to build JSON files), you can specify that 45# folder here. All text schemas will be copied to that folder. 46# 47# IMPORTANT: Make sure you quote all list arguments you pass to this function! 48# Otherwise CMake will only pass in the first element. 49# Example: build_flatbuffers("${fb_files}" "${include_dirs}" target_name ...) 50function(build_flatbuffers flatbuffers_schemas 51 schema_include_dirs 52 custom_target_name 53 additional_dependencies 54 generated_includes_dir 55 binary_schemas_dir 56 copy_text_schemas_dir) 57 58 # Test if including from FindFlatBuffers 59 if(FLATBUFFERS_FLATC_EXECUTABLE) 60 set(FLATC_TARGET "") 61 set(FLATC ${FLATBUFFERS_FLATC_EXECUTABLE}) 62 else() 63 set(FLATC_TARGET flatc) 64 set(FLATC flatc) 65 endif() 66 set(FLATC_SCHEMA_ARGS --gen-mutable) 67 if(FLATBUFFERS_FLATC_SCHEMA_EXTRA_ARGS) 68 set(FLATC_SCHEMA_ARGS 69 ${FLATBUFFERS_FLATC_SCHEMA_EXTRA_ARGS} 70 ${FLATC_SCHEMA_ARGS} 71 ) 72 endif() 73 74 set(working_dir "${CMAKE_CURRENT_SOURCE_DIR}") 75 76 set(schema_glob "*.fbs") 77 # Generate the include files parameters. 78 set(include_params "") 79 set(all_generated_files "") 80 foreach (include_dir ${schema_include_dirs}) 81 set(include_params -I ${include_dir} ${include_params}) 82 if (NOT ${copy_text_schemas_dir} STREQUAL "") 83 # Copy text schemas from dependent folders. 84 file(GLOB_RECURSE dependent_schemas ${include_dir}/${schema_glob}) 85 foreach (dependent_schema ${dependent_schemas}) 86 file(COPY ${dependent_schema} DESTINATION ${copy_text_schemas_dir}) 87 endforeach() 88 endif() 89 endforeach() 90 91 foreach(schema ${flatbuffers_schemas}) 92 get_filename_component(filename ${schema} NAME_WE) 93 # For each schema, do the things we requested. 94 if (NOT ${generated_includes_dir} STREQUAL "") 95 set(generated_include ${generated_includes_dir}/${filename}_generated.h) 96 add_custom_command( 97 OUTPUT ${generated_include} 98 COMMAND ${FLATC} ${FLATC_SCHEMA_ARGS} 99 -o ${generated_includes_dir} 100 ${include_params} 101 -c ${schema} 102 DEPENDS ${FLATC_TARGET} ${schema} ${additional_dependencies} 103 WORKING_DIRECTORY "${working_dir}") 104 list(APPEND all_generated_files ${generated_include}) 105 endif() 106 107 if (NOT ${binary_schemas_dir} STREQUAL "") 108 set(binary_schema ${binary_schemas_dir}/${filename}.bfbs) 109 add_custom_command( 110 OUTPUT ${binary_schema} 111 COMMAND ${FLATC} -b --schema 112 -o ${binary_schemas_dir} 113 ${include_params} 114 ${schema} 115 DEPENDS ${FLATC_TARGET} ${schema} ${additional_dependencies} 116 WORKING_DIRECTORY "${working_dir}") 117 list(APPEND all_generated_files ${binary_schema}) 118 endif() 119 120 if (NOT ${copy_text_schemas_dir} STREQUAL "") 121 file(COPY ${schema} DESTINATION ${copy_text_schemas_dir}) 122 endif() 123 endforeach() 124 125 # Create a custom target that depends on all the generated files. 126 # This is the target that you can depend on to trigger all these 127 # to be built. 128 add_custom_target(${custom_target_name} 129 DEPENDS ${all_generated_files} ${additional_dependencies}) 130 131 # Register the include directory we are using. 132 if (NOT ${generated_includes_dir} STREQUAL "") 133 include_directories(${generated_includes_dir}) 134 set_property(TARGET ${custom_target_name} 135 PROPERTY GENERATED_INCLUDES_DIR 136 ${generated_includes_dir}) 137 endif() 138 139 # Register the binary schemas dir we are using. 140 if (NOT ${binary_schemas_dir} STREQUAL "") 141 set_property(TARGET ${custom_target_name} 142 PROPERTY BINARY_SCHEMAS_DIR 143 ${binary_schemas_dir}) 144 endif() 145 146 # Register the text schema copy dir we are using. 147 if (NOT ${copy_text_schemas_dir} STREQUAL "") 148 set_property(TARGET ${custom_target_name} 149 PROPERTY COPY_TEXT_SCHEMAS_DIR 150 ${copy_text_schemas_dir}) 151 endif() 152endfunction() 153