Create a Windows shared library with DllMain funct

Question

I apologise if this has already been asked, but I have been trying to find an answer for many weeks now.

I am not particularly competent when it comes to shared libraries, however, using CLion RC 1.0 (and its integrated CMake) with MinGW, I have been unable to create a functional Windows DLL with a DllMain function. I did manage to create a .dll file, but it quickly became apparent that the symbol did not export corrrectly.

Simply put, I would like to see identical or similar behaviour to what is obtained with Visual Studio's default Win32 DLL template.

CMakeLists.txt

cmake_minimum_required(VERSION 3.1)
project(DllMainTest)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

set(SOURCE_FILES main.cpp)
add_library(DllMainTest SHARED ${SOURCE_FILES})

main.cpp

#include <windows.h>

extern "C" BOOL WINAPI DllMain(
    HINSTANCE hinstDLL,
    DWORD fdwReason,
    LPVOID lpvReserved
) {
switch(fdwReason) {
    case DLL_PROCESS_ATTACH:
        MessageBox(NULL, "It works!", "Status", MB_OK);
    case DLL_PROCESS_DETACH:
    case DLL_THREAD_ATTACH:
    case DLL_THREAD_DETACH:
    default:
        break;
    }
return TRUE;
}

EDIT: The intention for this DLL is to have it injected into a 32-bit process and for it to display a MessageBox on load.

Answer 1

check out the add_library documentation: http://www.cmake.org/cmake/help/v3.0/command/add_library.html

"STATIC libraries are archives of object files for use when linking other targets. SHARED libraries are linked dynamically and loaded at runtime. MODULE libraries are plugins that are not linked into other targets but may be loaded dynamically at runtime using dlopen-like functionality"

add_library(DllMainTest MODULE ${SOURCE_FILES})

should export the DllMain as intended.