From 8f98b9aa6b551f01dfdb0b4c38ff637876f025d9 Mon Sep 17 00:00:00 2001
From: SaeHie Park <saehie.park@gmail.com>
Date: Mon, 19 Aug 2024 14:44:25 +0900
Subject: [PATCH] [infra/fb] Introduce FlatBuffersMuteable_Target (#13687)

This will introduce FlatBuffersMuteable_Target method to produce schema
generated header with mutable methods.

ONE-DCO-1.0-Signed-off-by: SaeHie Park <saehie.park@gmail.com>
---
 .../FlatBuffersConfig.cmake                   | 49 +++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/infra/cmake/packages/FlatBuffers-23.5.26/FlatBuffersConfig.cmake b/infra/cmake/packages/FlatBuffers-23.5.26/FlatBuffersConfig.cmake
index d98882a32cc..cc77b844d1d 100644
--- a/infra/cmake/packages/FlatBuffers-23.5.26/FlatBuffersConfig.cmake
+++ b/infra/cmake/packages/FlatBuffers-23.5.26/FlatBuffersConfig.cmake
@@ -132,4 +132,53 @@ if(FlatBuffers_FOUND)
     target_include_directories(${TGT} PUBLIC "${ARG_INCLUDE_DIR}")
     target_link_libraries(${TGT} PUBLIC flatbuffers-23.5.26)
   endfunction(FlatBuffers_Target)
+
+  function(FlatBuffersMuteable_Target TGT)
+    set(oneValueArgs OUTPUT_DIR SCHEMA_DIR INCLUDE_DIR)
+    set(multiValueArgs SCHEMA_FILES)
+    cmake_parse_arguments(ARG "" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+
+    # Use OUTPUT_DIR as INCLUDE_DIR if INCLUDE_DIR is not specified
+    if(NOT ARG_INCLUDE_DIR)
+      set(ARG_INCLUDE_DIR ${ARG_OUTPUT_DIR})
+    endif(NOT ARG_INCLUDE_DIR)
+
+    get_filename_component(abs_output_dir ${ARG_OUTPUT_DIR} ABSOLUTE)
+    get_filename_component(abs_include_dir ${ARG_INCLUDE_DIR} ABSOLUTE)
+    get_filename_component(abs_schema_dir ${ARG_SCHEMA_DIR} ABSOLUTE)
+
+    # Let's reset list variables before using them
+    # NOTE THIS DOES NOT AFFECT parent scope
+    unset(SCHEMA_FILES)
+    unset(OUTPUT_FILES)
+
+    foreach(schema ${ARG_SCHEMA_FILES})
+      get_filename_component(schema_fn "${schema}" NAME)
+      get_filename_component(dir "${schema}" DIRECTORY)
+
+      get_filename_component(schema_fn_we "${schema_fn}" NAME_WE)
+
+      list(APPEND SCHEMA_FILES "${abs_schema_dir}/${schema}")
+      list(APPEND OUTPUT_FILES "${abs_output_dir}/${schema_fn_we}_generated.h")
+    endforeach()
+
+    # Generate headers
+    add_custom_command(OUTPUT ${OUTPUT_FILES}
+                       COMMAND ${CMAKE_COMMAND} -E make_directory "${abs_output_dir}"
+                       COMMAND "${FLATC_PATH}" -c --no-includes
+                               --no-union-value-namespacing
+                               --gen-object-api
+                               --gen-mutable
+                               -o "${abs_output_dir}"
+                               ${SCHEMA_FILES}
+                       DEPENDS ${SCHEMA_FILES}
+                       COMMENT "Generate '${TGT}' headers")
+
+    # NOTE This header-only library is deliberately declared as STATIC library
+    #      to avoid possible scope issues related with generated files
+    add_library(${TGT} STATIC ${OUTPUT_FILES})
+    set_target_properties(${TGT} PROPERTIES LINKER_LANGUAGE CXX)
+    target_include_directories(${TGT} PUBLIC "${ARG_INCLUDE_DIR}")
+    target_link_libraries(${TGT} PUBLIC flatbuffers-23.5.26)
+  endfunction(FlatBuffersMuteable_Target)
 endif(FlatBuffers_FOUND)