add csharp bindings with pinvoke and nuget packaging support

.github/workflows/ci.yml

@@ -115,6 +115,35 @@ jobs:
       run: |
         docker run --rm liblpm-go:ci
 
+  # C# bindings test
+  test-csharp-bindings:
+    name: Test C# 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 C# container
+      uses: docker/build-push-action@v6
+      with:
+        context: .
+        file: docker/Dockerfile.csharp
+        push: false
+        load: true
+        tags: liblpm-csharp:ci
+        cache-from: type=gha
+        cache-to: type=gha,mode=max
+
+    - name: Run C# tests
+      run: |
+        docker run --rm liblpm-csharp:ci
+
   # Lua bindings test
   test-lua-bindings:
     name: Test Lua Bindings
@@ -310,7 +339,7 @@ jobs:
   ci-summary:
     name: CI Summary
     runs-on: ubuntu-latest
-    needs: [build-and-test, test-cpp-bindings, test-go-bindings, test-lua-bindings, test-perl-bindings, test-php-bindings, test-python-bindings, code-quality]
+    needs: [build-and-test, test-cpp-bindings, test-go-bindings, test-csharp-bindings, test-lua-bindings, test-perl-bindings, test-php-bindings, test-python-bindings, code-quality]
     if: always()
 
     steps:
@@ -320,6 +349,7 @@ 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 "C# bindings: ${{ needs.test-csharp-bindings.result }}"
         echo "Lua bindings: ${{ needs.test-lua-bindings.result }}"
         echo "Perl bindings: ${{ needs.test-perl-bindings.result }}"
         echo "PHP bindings: ${{ needs.test-php-bindings.result }}"
@@ -330,6 +360,7 @@ jobs:
         if [[ "${{ needs.build-and-test.result }}" == "failure" ]] || \
            [[ "${{ needs.test-cpp-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-go-bindings.result }}" == "failure" ]] || \
+           [[ "${{ needs.test-csharp-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-lua-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-perl-bindings.result }}" == "failure" ]] || \
            [[ "${{ needs.test-php-bindings.result }}" == "failure" ]] || \

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_CSHARP_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)
@@ -421,6 +422,85 @@ if(BUILD_GO_WRAPPER)
     endif()
 endif()
 
+# C# wrapper
+if(BUILD_CSHARP_WRAPPER)
+    find_program(DOTNET_EXECUTABLE dotnet)
+    if(DOTNET_EXECUTABLE)
+        # Get .NET version
+        execute_process(
+            COMMAND ${DOTNET_EXECUTABLE} --version
+            OUTPUT_VARIABLE DOTNET_VERSION
+            OUTPUT_STRIP_TRAILING_WHITESPACE
+        )
+        message(STATUS "Found .NET SDK: ${DOTNET_VERSION}")
+
+        # Custom target to build C# wrapper
+        add_custom_target(csharp_wrapper ALL
+            COMMAND ${CMAKE_COMMAND} -E echo "Building C# wrapper..."
+            COMMAND ${DOTNET_EXECUTABLE} build --configuration Release
+            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/bindings/csharp
+            DEPENDS lpm
+            COMMENT "Building C# wrapper and bindings"
+        )
+
+        # Copy native library to runtimes directory after building
+        if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+            set(CSHARP_NATIVE_LIB_DIR "runtimes/linux-x64/native")
+            set(CSHARP_NATIVE_LIB_NAME "liblpm.so")
+        elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows")
+            set(CSHARP_NATIVE_LIB_DIR "runtimes/win-x64/native")
+            set(CSHARP_NATIVE_LIB_NAME "lpm.dll")
+        elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
+            set(CSHARP_NATIVE_LIB_DIR "runtimes/osx-x64/native")
+            set(CSHARP_NATIVE_LIB_NAME "liblpm.dylib")
+        endif()
+
+        add_custom_command(TARGET csharp_wrapper POST_BUILD
+            COMMAND ${CMAKE_COMMAND} -E make_directory 
+                ${CMAKE_CURRENT_SOURCE_DIR}/bindings/csharp/${CSHARP_NATIVE_LIB_DIR}
+            COMMAND ${CMAKE_COMMAND} -E copy_if_different
+                $<TARGET_FILE:lpm>
+                ${CMAKE_CURRENT_SOURCE_DIR}/bindings/csharp/${CSHARP_NATIVE_LIB_DIR}/${CSHARP_NATIVE_LIB_NAME}
+            COMMENT "Copying native library to C# runtimes directory"
+        )
+
+        # Custom target to test C# wrapper
+        add_custom_target(csharp_test
+            COMMAND ${CMAKE_COMMAND} -E env "LD_LIBRARY_PATH=${CMAKE_BINARY_DIR}:$ENV{LD_LIBRARY_PATH}"
+                ${DOTNET_EXECUTABLE} test --configuration Release --no-build
+            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/bindings/csharp
+            DEPENDS csharp_wrapper
+            COMMENT "Testing C# wrapper"
+        )
+
+        # Custom target to pack NuGet package
+        add_custom_target(csharp_pack
+            COMMAND ${DOTNET_EXECUTABLE} pack --configuration Release -o ${CMAKE_CURRENT_BINARY_DIR}/nupkg
+            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/bindings/csharp
+            DEPENDS csharp_wrapper
+            COMMENT "Creating NuGet package"
+        )
+
+        # Custom target to run C# examples
+        add_custom_target(csharp_example
+            COMMAND ${CMAKE_COMMAND} -E env "LD_LIBRARY_PATH=${CMAKE_BINARY_DIR}:$ENV{LD_LIBRARY_PATH}"
+                ${DOTNET_EXECUTABLE} run --configuration Release --project LibLpm.Examples
+            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/bindings/csharp
+            DEPENDS csharp_wrapper
+            COMMENT "Running C# examples"
+        )
+
+        message(STATUS "C# wrapper targets added:")
+        message(STATUS "  make csharp_wrapper - Build C# wrapper")
+        message(STATUS "  make csharp_test    - Run C# tests")
+        message(STATUS "  make csharp_pack    - Create NuGet package")
+        message(STATUS "  make csharp_example - Run C# examples")
+    else()
+        message(WARNING ".NET SDK not found. C# wrapper will not be built.")
+        message(WARNING "Install .NET SDK to build the wrapper: https://dotnet.microsoft.com/download")
+    endif()
+endif()
+
 # Lua wrapper
 if(BUILD_LUA_WRAPPER)
     add_subdirectory(bindings/lua)
@@ -576,6 +656,11 @@ if(BUILD_CPP_WRAPPER)
 else()
     message(STATUS "  Build C++ wrapper: OFF")
 endif()
+if(BUILD_CSHARP_WRAPPER AND DOTNET_EXECUTABLE)
+    message(STATUS "  Build C# wrapper: ON")
+else()
+    message(STATUS "  Build C# wrapper: OFF")
+endif()
 if(BUILD_LUA_WRAPPER)
     message(STATUS "  Build Lua wrapper: ON")
 else()

bindings/csharp/.gitignore

@@ -0,0 +1,52 @@
+# Build results
+[Dd]ebug/
+[Rr]elease/
+x64/
+x86/
+[Aa][Rr][Mm]/
+[Aa][Rr][Mm]64/
+bld/
+[Bb]in/
+[Oo]bj/
+[Ll]og/
+[Ll]ogs/
+
+# Visual Studio files
+.vs/
+*.user
+*.userosscache
+*.sln.docstates
+
+# NuGet packages
+*.nupkg
+*.snupkg
+nupkg/
+
+# Test results
+[Tt]est[Rr]esult*/
+[Bb]uild[Ll]og.*
+*.trx
+TestResults/
+
+# Coverage
+*.coverage
+*.coveragexml
+coverage/
+
+# JetBrains Rider
+.idea/
+
+# VS Code
+.vscode/
+
+# macOS
+.DS_Store
+
+# Native libraries (populated during build)
+# Don't ignore runtimes/ structure, but ignore actual binaries
+runtimes/**/native/*.so
+runtimes/**/native/*.dll
+runtimes/**/native/*.dylib
+
+# Project-specific
+*.received.*

bindings/csharp/CMakeLists.txt

@@ -0,0 +1,102 @@
+cmake_minimum_required(VERSION 3.16)
+
+# C# wrapper for liblpm
+project(liblpm_csharp VERSION 2.0.0)
+
+# Find .NET SDK
+find_program(DOTNET_EXECUTABLE dotnet)
+
+if(NOT DOTNET_EXECUTABLE)
+    message(FATAL_ERROR "dotnet not found. Install .NET SDK to build C# wrapper.")
+endif()
+
+# Get .NET version
+execute_process(
+    COMMAND ${DOTNET_EXECUTABLE} --version
+    OUTPUT_VARIABLE DOTNET_VERSION
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+message(STATUS "Found .NET SDK: ${DOTNET_VERSION}")
+
+# Find or import lpm library
+if(NOT TARGET lpm)
+    set(LPM_ROOT_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../..")
+    if(EXISTS "${LPM_ROOT_DIR}/include/lpm.h")
+        message(STATUS "Using liblpm from parent project")
+    else()
+        find_library(LPM_LIBRARY NAMES lpm)
+        if(LPM_LIBRARY)
+            message(STATUS "Found system liblpm: ${LPM_LIBRARY}")
+        else()
+            message(FATAL_ERROR "liblpm not found. Build the main project first or install liblpm.")
+        endif()
+    endif()
+endif()
+
+# Configuration
+set(CSHARP_BUILD_CONFIG "$<IF:$<CONFIG:Debug>,Debug,Release>")
+
+# Build C# wrapper
+add_custom_target(csharp_wrapper ALL
+    COMMAND ${DOTNET_EXECUTABLE} build --configuration ${CSHARP_BUILD_CONFIG}
+    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+    DEPENDS lpm
+    COMMENT "Building C# wrapper"
+    VERBATIM
+)
+
+# Test C# wrapper
+add_custom_target(csharp_test
+    COMMAND ${DOTNET_EXECUTABLE} test --configuration ${CSHARP_BUILD_CONFIG} --no-build
+    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+    DEPENDS csharp_wrapper
+    COMMENT "Testing C# wrapper"
+    VERBATIM
+)
+
+# Pack NuGet package
+add_custom_target(csharp_pack
+    COMMAND ${DOTNET_EXECUTABLE} pack --configuration Release -o ${CMAKE_CURRENT_BINARY_DIR}/nupkg
+    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+    DEPENDS csharp_wrapper
+    COMMENT "Creating NuGet package"
+    VERBATIM
+)
+
+# Run examples
+add_custom_target(csharp_example
+    COMMAND ${DOTNET_EXECUTABLE} run --configuration ${CSHARP_BUILD_CONFIG} --project LibLpm.Examples
+    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+    DEPENDS csharp_wrapper
+    COMMENT "Running C# examples"
+    VERBATIM
+)
+
+# Copy native library to runtimes directory for local development
+if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+    set(NATIVE_LIB_DIR "runtimes/linux-x64/native")
+    set(NATIVE_LIB_NAME "liblpm.so")
+elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows")
+    set(NATIVE_LIB_DIR "runtimes/win-x64/native")
+    set(NATIVE_LIB_NAME "lpm.dll")
+elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
+    set(NATIVE_LIB_DIR "runtimes/osx-x64/native")
+    set(NATIVE_LIB_NAME "liblpm.dylib")
+endif()
+
+add_custom_command(TARGET csharp_wrapper POST_BUILD
+    COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_CURRENT_SOURCE_DIR}/${NATIVE_LIB_DIR}
+    COMMAND ${CMAKE_COMMAND} -E copy_if_different
+        $<TARGET_FILE:lpm>
+        ${CMAKE_CURRENT_SOURCE_DIR}/${NATIVE_LIB_DIR}/${NATIVE_LIB_NAME}
+    COMMENT "Copying native library to runtimes directory"
+    VERBATIM
+)
+
+message(STATUS "C# wrapper configuration:")
+message(STATUS "  .NET SDK: ${DOTNET_VERSION}")
+message(STATUS "  Build targets:")
+message(STATUS "    make csharp_wrapper - Build C# wrapper")
+message(STATUS "    make csharp_test    - Run C# tests")
+message(STATUS "    make csharp_pack    - Create NuGet package")
+message(STATUS "    make csharp_example - Run examples")

bindings/csharp/Dockerfile

@@ -0,0 +1,46 @@
+# Dockerfile for C# bindings CI testing
+FROM mcr.microsoft.com/dotnet/sdk:8.0
+
+# Install C build tools for native library compilation
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    build-essential \
+    gcc \
+    cmake \
+    ninja-build \
+    git \
+    pkg-config \
+    libc6-dev \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /build
+
+# Copy the entire liblpm project
+COPY . /build/
+
+# Initialize submodules and build liblpm native library
+RUN git config --global --add safe.directory /build && \
+    if [ -f .gitmodules ]; then git submodule update --init --recursive; fi && \
+    mkdir -p build && cd build && \
+    cmake -DCMAKE_BUILD_TYPE=Release -GNinja .. && \
+    ninja && \
+    ninja install && \
+    ldconfig
+
+# Copy native library to runtimes directory
+RUN mkdir -p /build/bindings/csharp/runtimes/linux-x64/native && \
+    cp /build/build/liblpm.so /build/bindings/csharp/runtimes/linux-x64/native/
+
+# Build and test C# bindings
+WORKDIR /build/bindings/csharp
+
+# Restore dependencies
+RUN dotnet restore
+
+# Build in Release mode
+RUN dotnet build --configuration Release --no-restore
+
+# Run tests
+RUN dotnet test --configuration Release --no-build --verbosity normal
+
+# Default command: run tests
+CMD ["dotnet", "test", "--configuration", "Release", "--verbosity", "normal"]