Generate and ship FFI metadata with ASTrein

.github/workflows/build_binary.yml

@@ -15,6 +15,9 @@ jobs:
   build-binary:
     name: 'Build binary'
     runs-on: ubuntu-latest
+    env:
+      ASTREIN_VERSION: '1.1.0'
+      ASTREIN_SHA256: 'd5964319ea5a3742e4d7223ee5963d6aa3b24c8f67ef75c61d591c635f413497'
     permissions:
       contents: write
 
@@ -30,6 +33,19 @@ jobs:
           version: '16'
           platform: 'x64'
 
+      - name: 'Download ASTrein'
+        run: |
+          curl --fail --location \
+            --output "${RUNNER_TEMP}/astrein-linux-x86_64.tar.gz" \
+            "https://github.com/Katze719/ASTrein/releases/download/v${ASTREIN_VERSION}/astrein-linux-x86_64.tar.gz"
+          echo "${ASTREIN_SHA256}  ${RUNNER_TEMP}/astrein-linux-x86_64.tar.gz" \
+            | sha256sum --check -
+          mkdir -p "${RUNNER_TEMP}/astrein"
+          tar -xzf "${RUNNER_TEMP}/astrein-linux-x86_64.tar.gz" \
+            -C "${RUNNER_TEMP}/astrein" \
+            --strip-components=1
+          "${RUNNER_TEMP}/astrein/bin/astrein" --version
+
       - name: 'Setup CMake'
         uses: jwlawson/actions-setup-cmake@v2
         with:
@@ -39,13 +55,16 @@ jobs:
         run: |
           cmake --preset linux-gcc-release \
             -DCMAKE_C_COMPILER=gcc-16 \
-            -DCMAKE_CXX_COMPILER=g++-16
+            -DCMAKE_CXX_COMPILER=g++-16 \
+            -DCPP_BINDINGS_LINUX_ENABLE_FFI_JSON_EXPORT=ON \
+            -DCPP_BINDINGS_LINUX_ASTREIN_EXECUTABLE="${RUNNER_TEMP}/astrein/bin/astrein"
 
       - name: 'Build'
         run: |
-          cmake --build --preset linux-gcc-release --target cpp_bindings_linux
+          cmake --build --preset linux-gcc-release \
+            --target cpp_bindings_linux cpp_bindings_linux_ffi_json
 
-      - name: 'Set PACKAGE_VERSION from env.bat'
+      - name: 'Set PACKAGE_VERSION from env.sh'
         id: version
         run: |
           . build/env.sh
@@ -70,7 +89,9 @@ jobs:
         with:
           if-no-files-found: error
           name: libcpp_bindings_linux
-          path: build/libcpp_bindings_linux.so
+          path: |
+            build/libcpp_bindings_linux.so
+            build/cpp_bindings_linux.ffi.json
 
       - name: 'Create GitHub Release'
         if: github.ref_type == 'tag' && steps.check-tag.outputs.IS_VALID_PACKAGE_VERSION == 'true'
@@ -79,7 +100,9 @@ jobs:
           name: 'v${{ steps.version.outputs.PACKAGE_VERSION }}'
           tag_name: ${{ github.ref_name }}
           generate_release_notes: true
-          files: build/out/libcpp_bindings_windows.dll
+          files: |
+            build/libcpp_bindings_windows.so
+            build/cpp_bindings_linux.ffi.json
 
     outputs:
       package_version: ${{ steps.version.outputs.PACKAGE_VERSION }}

.github/workflows/publish_jsr.yml

@@ -50,6 +50,7 @@ jobs:
         run: |
           mkdir -p ./jsr/bin
           cp ./artifacts/libcpp_bindings_linux.so ./jsr/bin/x86_64.so
+          cp ./artifacts/cpp_bindings_linux.ffi.json ./jsr/bin/x86_64.ffi.json
 
           ./jsr/scripts/binary_to_json.sh \
             ./artifacts/libcpp_bindings_linux.so \
@@ -71,4 +72,3 @@ jobs:
         working-directory: jsr
         run: |
           deno publish --allow-dirty --dry-run
-

CMakeLists.txt

@@ -34,15 +34,116 @@ set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_CXX_MODULE_STD 26)
 set(CMAKE_CXX_MODULE_EXTENSIONS OFF)
 
+option(
+    CPP_BINDINGS_LINUX_ENABLE_FFI_JSON_EXPORT
+    "Enable ASTrein JSON export for the cpp-core FFI headers"
+    OFF
+)
+set(
+    CPP_BINDINGS_LINUX_ASTREIN_EXECUTABLE
+    ""
+    CACHE FILEPATH
+    "Path to the ASTrein executable used for FFI JSON export"
+)
+set(
+    CPP_BINDINGS_LINUX_FFI_JSON_OUTPUT
+    "${CMAKE_BINARY_DIR}/cpp_bindings_linux.ffi.json"
+    CACHE FILEPATH
+    "Output path for the generated cpp-core FFI API metadata"
+)
+
 CPMAddPackage(
     NAME cpp_core
     GITHUB_REPOSITORY Serial-IO/cpp-core
-    GIT_TAG v2.0.0
+    GIT_TAG v2.0.1
     OPTIONS
     "CMAKE_EXPORT_COMPILE_COMMANDS OFF"
-    "CPP_CORE_ENABLE_AST_EXPORT ON"
 )
 
+if(CPP_BINDINGS_LINUX_ENABLE_FFI_JSON_EXPORT)
+    if(CPP_BINDINGS_LINUX_ASTREIN_EXECUTABLE)
+        set(_cpp_bindings_linux_astrein "${CPP_BINDINGS_LINUX_ASTREIN_EXECUTABLE}")
+    else()
+        find_program(_cpp_bindings_linux_astrein NAMES astrein)
+    endif()
+
+    if(NOT _cpp_bindings_linux_astrein)
+        message(
+            FATAL_ERROR
+            "CPP_BINDINGS_LINUX_ENABLE_FFI_JSON_EXPORT=ON requires ASTrein. "
+            "Install astrein or set CPP_BINDINGS_LINUX_ASTREIN_EXECUTABLE."
+        )
+    endif()
+
+    file(
+        GLOB_RECURSE _cpp_bindings_linux_ffi_headers
+        CONFIGURE_DEPENDS
+        "${cpp_core_SOURCE_DIR}/include/*.h"
+        "${cpp_core_SOURCE_DIR}/include/*.hpp"
+    )
+    set(
+        _cpp_bindings_linux_ffi_wrapper
+        "${CMAKE_BINARY_DIR}/ffi.cpp"
+    )
+    get_filename_component(
+        _cpp_bindings_linux_ffi_output_dir
+        "${CPP_BINDINGS_LINUX_FFI_JSON_OUTPUT}"
+        DIRECTORY
+    )
+
+    file(
+        GENERATE
+        OUTPUT "${_cpp_bindings_linux_ffi_wrapper}"
+        CONTENT "#include <cpp_core/serial.h>\n"
+    )
+
+    add_library(
+        cpp_bindings_linux_ffi_ast_context
+        OBJECT
+        EXCLUDE_FROM_ALL
+        "${_cpp_bindings_linux_ffi_wrapper}"
+    )
+    target_include_directories(
+        cpp_bindings_linux_ffi_ast_context
+        PRIVATE
+        "${cpp_core_SOURCE_DIR}/include"
+    )
+    target_compile_features(
+        cpp_bindings_linux_ffi_ast_context
+        PRIVATE
+        cxx_std_26
+    )
+
+    add_custom_command(
+        OUTPUT "${CPP_BINDINGS_LINUX_FFI_JSON_OUTPUT}"
+        COMMAND
+            ${CMAKE_COMMAND} -E make_directory
+            "${_cpp_bindings_linux_ffi_output_dir}"
+        COMMAND
+            "${_cpp_bindings_linux_astrein}"
+            --ffi
+            --compile-commands "${CMAKE_BINARY_DIR}/compile_commands.json"
+            --require-c-linkage
+            --require-default-visibility
+            --public-header "cpp_core/serial.h"
+            --api-root "${cpp_core_SOURCE_DIR}/include"
+            --output "${CPP_BINDINGS_LINUX_FFI_JSON_OUTPUT}"
+            "${_cpp_bindings_linux_ffi_wrapper}"
+        DEPENDS
+            "${_cpp_bindings_linux_astrein}"
+            "${CMAKE_BINARY_DIR}/compile_commands.json"
+            "${_cpp_bindings_linux_ffi_wrapper}"
+            ${_cpp_bindings_linux_ffi_headers}
+        COMMENT "Exporting cpp-core FFI API metadata with ASTrein"
+        VERBATIM
+    )
+
+    add_custom_target(
+        cpp_bindings_linux_ffi_json
+        DEPENDS "${CPP_BINDINGS_LINUX_FFI_JSON_OUTPUT}"
+    )
+endif()
+
 CPMAddPackage(
     NAME GTest
     GITHUB_REPOSITORY google/googletest

jsr/README.md

@@ -5,6 +5,11 @@
 
 Binaries are provided as a [package on JSR](https://jsr.io/@serial/cpp-bindings-linux). They are serialized as a base64 string inside the JSON file.
 
+The package also includes cpp-core FFI API metadata generated with
+[ASTrein](https://github.com/Katze719/ASTrein) at `bin/x86_64.ffi.json`.
+It describes the exported C symbols, parameter and return types, callbacks,
+default values, and API documentation used by downstream FFI adapter generators.
+
 This package is primarily intended as a dependency for [`@serial/serial`](https://jsr.io/@serial/serial). However, it can also be used independently.
 
 

jsr/jsr.json

@@ -19,5 +19,3 @@
     ]
   }
 }
-
-