add lua bindings with luarocks packaging support

.github/workflows/ci.yml

@@ -115,6 +115,35 @@ jobs:
       run: |
         docker run --rm liblpm-go:ci
 
+  # Lua bindings test
+  test-lua-bindings:
+    name: Test Lua Bindings
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v6
+      with:
+        submodules: recursive
+
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
+
+    - name: Build Lua container
+      uses: docker/build-push-action@v6
+      with:
+        context: .
+        file: docker/Dockerfile.lua
+        push: false
+        load: true
+        tags: liblpm-lua:ci
+        cache-from: type=gha
+        cache-to: type=gha,mode=max
+
+    - name: Run Lua tests
+      run: |
+        docker run --rm liblpm-lua:ci
+
   # Perl bindings test
   test-perl-bindings:
     name: Test Perl Bindings
@@ -281,7 +310,7 @@ jobs:
   ci-summary:
     name: CI Summary
     runs-on: ubuntu-latest
-    needs: [build-and-test, test-cpp-bindings, test-go-bindings, test-perl-bindings, test-php-bindings, test-python-bindings, code-quality]
+    needs: [build-and-test, test-cpp-bindings, test-go-bindings, test-lua-bindings, test-perl-bindings, test-php-bindings, test-python-bindings, code-quality]
     if: always()
 
     steps:
@@ -291,6 +320,7 @@ jobs:
         echo "Build and test: ${{ needs.build-and-test.result }}"
         echo "C++ bindings: ${{ needs.test-cpp-bindings.result }}"
         echo "Go bindings: ${{ needs.test-go-bindings.result }}"
+        echo "Lua bindings: ${{ needs.test-lua-bindings.result }}"
         echo "Perl bindings: ${{ needs.test-perl-bindings.result }}"
         echo "PHP bindings: ${{ needs.test-php-bindings.result }}"
         echo "Python bindings: ${{ needs.test-python-bindings.result }}"
@@ -300,6 +330,7 @@ jobs:
         if [[ "${{ needs.build-and-test.result }}" == "failure" ]] || \
            [[ "${{ needs.test-cpp-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-go-bindings.result }}" == "failure" ]] || \
+           [[ "${{ needs.test-lua-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-perl-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-php-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-python-bindings.result }}" == "failure" ]]; then

CMakeLists.txt

@@ -61,6 +61,7 @@ option(WITH_DPDK_BENCHMARK "Build DPDK comparison benchmark" OFF)
 option(WITH_EXTERNAL_LPM_BENCHMARK "Build benchmarks with external LPM libraries" OFF)
 option(BUILD_GO_WRAPPER "Build Go wrapper and bindings" OFF)
 option(BUILD_CPP_WRAPPER "Build C++ wrapper and bindings" OFF)
+option(BUILD_LUA_WRAPPER "Build Lua wrapper and bindings" OFF)
 option(BUILD_PERL_WRAPPER "Build Perl wrapper and bindings" OFF)
 option(BUILD_PHP_WRAPPER "Build PHP wrapper and bindings" OFF)
 option(BUILD_PYTHON_WRAPPER "Build Python wrapper and bindings" OFF)
@@ -420,6 +421,11 @@ if(BUILD_GO_WRAPPER)
     endif()
 endif()
 
+# Lua wrapper
+if(BUILD_LUA_WRAPPER)
+    add_subdirectory(bindings/lua)
+endif()
+
 # Perl wrapper
 if(BUILD_PERL_WRAPPER)
     find_program(PERL_EXECUTABLE perl)
@@ -507,6 +513,24 @@ if(BUILD_PHP_WRAPPER)
     endif()
 endif()
 
+# Python wrapper
+if(BUILD_PYTHON_WRAPPER)
+    find_package(Python COMPONENTS Interpreter Development.Module)
+    find_program(CYTHON_EXECUTABLE NAMES cython cython3)
+    if(Python_FOUND AND CYTHON_EXECUTABLE)
+        message(STATUS "Found Python: ${Python_EXECUTABLE} (${Python_VERSION})")
+        message(STATUS "Found Cython: ${CYTHON_EXECUTABLE}")
+        add_subdirectory(bindings/python)
+    else()
+        if(NOT Python_FOUND)
+            message(WARNING "Python not found, skipping Python bindings")
+        endif()
+        if(NOT CYTHON_EXECUTABLE)
+            message(WARNING "Cython not found, skipping Python bindings. Install with: pip install cython")
+        endif()
+    endif()
+endif()
+
 # Print configuration summary
 message(STATUS "liblpm configuration:")
 message(STATUS "  Version: ${PROJECT_VERSION}")
@@ -552,6 +576,11 @@ if(BUILD_CPP_WRAPPER)
 else()
     message(STATUS "  Build C++ wrapper: OFF")
 endif()
+if(BUILD_LUA_WRAPPER)
+    message(STATUS "  Build Lua wrapper: ON")
+else()
+    message(STATUS "  Build Lua wrapper: OFF")
+endif()
 if(BUILD_PERL_WRAPPER AND PERL_EXECUTABLE)
     message(STATUS "  Build Perl wrapper: ON")
 else()

bindings/lua/CMakeLists.txt

@@ -0,0 +1,208 @@
+# ============================================================================
+# CMakeLists.txt for liblpm Lua bindings
+# ============================================================================
+#
+# Supports:
+#   - Lua 5.3, 5.4, and LuaJIT 2.1+
+#   - CMake 3.16+
+#
+# Build options:
+#   cmake -DBUILD_LUA_WRAPPER=ON ..
+#
+# Targets:
+#   lpm_lua     - Lua C module (shared library)
+#   lua_test    - Run Lua tests
+#   lua_example - Run basic example
+#
+# ============================================================================
+
+cmake_minimum_required(VERSION 3.16)
+
+# ============================================================================
+# Find Lua
+# ============================================================================
+
+# Try to find Lua using CMake's FindLua module
+# This will search for Lua 5.4, 5.3, 5.2, 5.1 in order
+find_package(Lua)
+
+if(NOT LUA_FOUND)
+    # Try pkg-config as fallback
+    find_package(PkgConfig QUIET)
+    if(PkgConfig_FOUND)
+        # Try specific versions
+        pkg_check_modules(LUA QUIET lua5.4)
+        if(NOT LUA_FOUND)
+            pkg_check_modules(LUA QUIET lua5.3)
+        endif()
+        if(NOT LUA_FOUND)
+            pkg_check_modules(LUA QUIET luajit)
+        endif()
+        if(NOT LUA_FOUND)
+            pkg_check_modules(LUA QUIET lua)
+        endif()
+    endif()
+endif()
+
+if(NOT LUA_FOUND)
+    message(WARNING "Lua not found. Lua bindings will not be built.")
+    message(WARNING "Install Lua development files:")
+    message(WARNING "  Ubuntu/Debian: sudo apt install liblua5.4-dev")
+    message(WARNING "  Fedora:        sudo dnf install lua-devel")
+    message(WARNING "  macOS:         brew install lua")
+    return()
+endif()
+
+# Check Lua version (require 5.3+)
+if(LUA_VERSION_STRING VERSION_LESS "5.3")
+    message(WARNING "Lua ${LUA_VERSION_STRING} found, but 5.3+ is required.")
+    message(WARNING "Lua bindings will not be built.")
+    return()
+endif()
+
+message(STATUS "Found Lua: ${LUA_VERSION_STRING}")
+message(STATUS "  Include: ${LUA_INCLUDE_DIR}")
+message(STATUS "  Library: ${LUA_LIBRARIES}")
+
+# ============================================================================
+# Lua C Module
+# ============================================================================
+
+# Source files
+set(LPM_LUA_SOURCES
+    src/liblpm.c
+    src/liblpm_utils.c
+)
+
+# Create shared library module
+add_library(lpm_lua MODULE ${LPM_LUA_SOURCES})
+
+# Set output name to match Lua's require() expectations
+# The module will be named "liblpm.so" (or .dll on Windows)
+set_target_properties(lpm_lua PROPERTIES
+    OUTPUT_NAME "liblpm"
+    PREFIX ""
+    SUFFIX ".so"
+)
+
+# Platform-specific suffix
+if(APPLE)
+    set_target_properties(lpm_lua PROPERTIES SUFFIX ".so")
+elseif(WIN32)
+    set_target_properties(lpm_lua PROPERTIES SUFFIX ".dll")
+endif()
+
+# Include directories
+target_include_directories(lpm_lua PRIVATE
+    ${LUA_INCLUDE_DIR}
+    ${CMAKE_SOURCE_DIR}/include
+)
+
+# Link against liblpm shared library
+# Note: The liblpm.so must be loadable (in LD_LIBRARY_PATH or installed)
+# before the Lua module is loaded, due to ifunc resolver requirements
+target_link_libraries(lpm_lua PRIVATE
+    lpm
+    ${LUA_LIBRARIES}
+)
+
+# Set RPATH to find liblpm.so in the build directory and install location
+set_target_properties(lpm_lua PROPERTIES
+    BUILD_RPATH "${CMAKE_BINARY_DIR}"
+    INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}"
+)
+
+# C standard
+set_target_properties(lpm_lua PROPERTIES
+    C_STANDARD 11
+    C_STANDARD_REQUIRED ON
+)
+
+# Compiler flags
+if(CMAKE_C_COMPILER_ID MATCHES "GNU|Clang")
+    target_compile_options(lpm_lua PRIVATE
+        -Wall -Wextra -Wpedantic
+        -Wno-unused-parameter
+    )
+endif()
+
+# ============================================================================
+# Installation
+# ============================================================================
+
+# Determine Lua install path
+if(DEFINED LUA_CPATH)
+    set(LUA_INSTALL_CPATH ${LUA_CPATH})
+else()
+    # Default to standard Lua cpath
+    # This can be overridden with -DLUA_CPATH=/path/to/lua/cpath
+    set(LUA_INSTALL_CPATH "${CMAKE_INSTALL_LIBDIR}/lua/${LUA_VERSION_MAJOR}.${LUA_VERSION_MINOR}")
+endif()
+
+install(TARGETS lpm_lua
+    LIBRARY DESTINATION ${LUA_INSTALL_CPATH}
+    RUNTIME DESTINATION ${LUA_INSTALL_CPATH}
+)
+
+# ============================================================================
+# Test Target
+# ============================================================================
+
+# Find Lua interpreter
+find_program(LUA_EXECUTABLE
+    NAMES lua${LUA_VERSION_MAJOR}.${LUA_VERSION_MINOR} lua
+    HINTS ${LUA_INCLUDE_DIR}/../bin
+)
+
+if(LUA_EXECUTABLE)
+    message(STATUS "Lua interpreter: ${LUA_EXECUTABLE}")
+
+    # Test target
+    # Note: LD_PRELOAD is required to ensure liblpm.so's ifunc resolvers are
+    # executed before the Lua module is loaded via dlopen
+    add_custom_target(lua_test
+        COMMAND ${CMAKE_COMMAND} -E env 
+            "LD_PRELOAD=${CMAKE_BINARY_DIR}/liblpm.so"
+            "LUA_CPATH=${CMAKE_CURRENT_BINARY_DIR}/?.so"
+            ${LUA_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/tests/test_lpm.lua
+        DEPENDS lpm_lua lpm
+        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+        COMMENT "Running Lua tests"
+    )
+
+    # Example target
+    add_custom_target(lua_example
+        COMMAND ${CMAKE_COMMAND} -E env 
+            "LD_PRELOAD=${CMAKE_BINARY_DIR}/liblpm.so"
+            "LUA_CPATH=${CMAKE_CURRENT_BINARY_DIR}/?.so"
+            ${LUA_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/examples/basic_example.lua
+        DEPENDS lpm_lua lpm
+        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+        COMMENT "Running Lua basic example"
+    )
+
+    # Add to CTest
+    if(BUILD_TESTS)
+        add_test(NAME lua_wrapper_test
+            COMMAND ${CMAKE_COMMAND} -E env
+                "LD_PRELOAD=${CMAKE_BINARY_DIR}/liblpm.so"
+                "LUA_CPATH=${CMAKE_CURRENT_BINARY_DIR}/?.so"
+                ${LUA_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/tests/test_lpm.lua
+            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+        )
+    endif()
+else()
+    message(WARNING "Lua interpreter not found. Test targets will not be available.")
+endif()
+
+# ============================================================================
+# Summary
+# ============================================================================
+
+message(STATUS "Lua bindings configuration:")
+message(STATUS "  Lua version: ${LUA_VERSION_STRING}")
+message(STATUS "  Install path: ${LUA_INSTALL_CPATH}")
+if(LUA_EXECUTABLE)
+    message(STATUS "  Test command: make lua_test")
+    message(STATUS "  Example command: make lua_example")
+endif()