feature: example module

Signed-off-by: Dmitriy Khaustov aka xDimon <[email protected]>

# Conflicts:
#	src/modules/module.hpp

Author: xDimon

CMakeLists.txt

@@ -15,6 +15,7 @@ set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+set(CMAKE_EXPERIMENTAL_CXX_MODULE_CMAKE_API ON)
 
 project(cpp-jam
     VERSION 0.0.1
@@ -40,6 +41,12 @@ find_package(Boost.DI CONFIG REQUIRED)
 find_package(qtils CONFIG REQUIRED)
 find_package(prometheus-cpp CONFIG REQUIRED)
 
+if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+  add_compile_options(-fmodules-ts)
+elseif(CMAKE_CXX_COMPILER_ID MATCHES "Clang|AppleClang")
+  add_compile_options(-fmodules)
+endif()
+
 add_library(headers INTERFACE)
 target_include_directories(headers INTERFACE
     $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src_>

src/modules/CMakeLists.txt

@@ -11,3 +11,8 @@ add_library(modules
 target_link_libraries(modules
     qtils::qtils
     )
+
+# -------------- Modules --------------
+
+# Example module
+add_subdirectory(example)

src/modules/example/CMakeLists.txt

@@ -0,0 +1,36 @@
+#
+# Copyright Quadrivium LLC
+# All Rights Reserved
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# Create a shared module library
+add_library(example_module MODULE # or SHARED
+    example.cpp
+)
+
+# Set C++ standard
+target_compile_features(example_module PRIVATE
+    cxx_std_20
+)
+
+# Set include directories
+target_include_directories(example_module PRIVATE
+    ${CMAKE_CURRENT_SOURCE_DIR}
+)
+
+# Set exported symbols visibility
+set_target_properties(example_module PROPERTIES
+    CXX_VISIBILITY_PRESET hidden
+    VISIBILITY_INLINES_HIDDEN ON
+)
+
+# Ensure exported symbols are explicitly marked
+target_compile_definitions(example_module PRIVATE
+    EXAMPLE_EXPORTS
+)
+
+# Link with libs
+target_link_libraries(example_module
+    qtils::qtils
+)

src/modules/example/example.cpp

@@ -0,0 +1,39 @@
+/**
+ * Copyright Quadrivium LLC
+ * All Rights Reserved
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "modules/example/example.hpp"
+
+MODULE_C_API const uint64_t JAM_MAGIC = jam::modules::JAM_MAGIC;
+
+std::shared_ptr<jam::modules::ExampleModule> module_instance;
+
+MODULE_C_API const char *loader_id() {
+  return "ExampleLoader";
+}
+
+MODULE_C_API const char *get_module_name_and_version() {
+  return "ExampleModule v1.0";
+}
+
+std::string path_;
+std::unique_ptr<void, decltype(&dlclose)> handle_{};
+std::string loader_id_;
+
+MODULE_API std::weak_ptr<jam::modules::ExampleModule> query_module_instance() {
+  static bool _ = ({
+    module_instance = jam::modules::ExampleModule::create_shared(
+        path_,               // path
+        std::move(handle_),  // handler
+        loader_id_           // loader
+    );
+    true;
+  });
+  return module_instance;
+}
+
+MODULE_API void release_module_instance() {
+  module_instance = nullptr;
+};

src/modules/example/example.hpp

@@ -0,0 +1,42 @@
+/**
+ * Copyright Quadrivium LLC
+ * All Rights Reserved
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <modules/module.hpp>
+
+/// @brief Magic word to check if module is JAM module actually
+MODULE_C_API const uint64_t JAM_MAGIC;
+
+/// @brief Identifier of suitable module loader
+MODULE_C_API const char *loader_id();
+
+/// @brief Returns module name and version
+/// @return A string containing module name and version
+MODULE_C_API const char *get_module_name_and_version();
+
+namespace jam::modules {
+  class ExampleModule;
+}
+
+MODULE_API std::weak_ptr<jam::modules::ExampleModule> query_module_instance();
+
+MODULE_API void release_module_instance();
+
+class BlockTree;
+class ExampleModuleLoader;
+
+namespace jam::modules {
+
+  class ExampleModule : public Module, Singleton<ExampleModule> {  // implement by module
+    using Module::Module;
+    virtual ~ExampleModule() = default;
+    CREATE_SHARED_METHOD(ExampleModule);
+    // virtual void initialize(std::shared_ptr<BlockTree> tree,
+    //                         std::weak_ptr<ExampleModuleLoader> loader) = 0;
+  };
+
+}  // namespace jam::modules