Ulfius failed to link microhttpd on mingw64 using CMake

[raccoman]

Describe the issue
I'm trying to link ulfius to my cmake project on Windows. I would like to have ulfius sourcecode inside my libs/ folder, then let cmake compile using add_subdirectory(libs/ulfius) and directly linking target ulfius_static. It seems to works just fine except for microhttpd.

To Reproduce
I cloned ulfius inside libs/ folder, then I downloaded microhttpd-w32-bin.zip extracted the libmicrohttpd-0.9.77-w32-bin\x86_64\MinGW\static\mingw64 contents inside libs/. Then I copied an Ulfius example and compiled my porject using Cmake (crf. Additional Context)

Expected behavior
It should successfully compile

Screenshots

System (please complete the following information):

• Windows 11
• Ulfius 2.7.13
• git clone

Additional context
Here is my CMakeLists.txt

cmake_minimum_required(VERSION 3.22.1)
project(myapp C)

if (WIN32)
    set(MHD_LIBRARY ${PROJECT_SOURCE_DIR}/libs/microhttpd-w32/lib/libmicrohttpd.a)
    set(MHD_INCLUDE_DIR ${PROJECT_SOURCE_DIR}/libs/microhttpd-w32/include)
endif ()
add_subdirectory(libs/ulfius-2.7.13)


include_directories(include)
set(SOURCES)

add_executable(${PROJECT_NAME} main.c ${SOURCES})

target_link_libraries(${PROJECT_NAME}
        ulfius_static)

if (NOT WIN32)
    target_link_libraries(${PROJECT_NAME} m)
endif ()

[babelouest]

Hello,

Unfortunately, I don't know much on windows build or mingw64, I believe it's possible since I think other were able to build it, but I wouldn't know how.

[4cecoder]

I've been looking into this as well and still haven't found a smooth solution to building ulfius on windows

However, maybe trying zig cc command to build on windows.

link your libs and stuff and disable websockets to build easier for windows

With some tweaking of this command, I think we might be able to get some results on windows

zig cc -I /path/to/libmicrohttpd/bin -I /path/to/orcania -I /path/to/yder -o ulfius.o ulfius.c

[pmcgaugh]

EDIT: ...after working through this one more, I've realized I was linking in the DLL and avoiding the missing ws2_32 dependency. I am continuing to look through fixes to the linking.

ORIGINAL POST
Before I start, I appreciate the Zig mention...I've been on a learning spree, and it's cool to see it show up in some C projects randomly!

I have had the same issue with the Windows MinGW build and the missing linked WinSock libraries.

My solution was to add target_link_libraries(ulfius PRIVATE ws2_32) to my application CMake...full code block below:

option(BUILD_STATIC "..." ON)
option(WITH_GNUTLS "..." OFF)
option(WITH_WEBSOCKET "..." OFF)
option(WITH_CURL "..." OFF)
option(WITH_JANSSON "..." OFF)
option(WITH_YDER "..." OFF)
option(BUILD_UWSC "..." OFF)
set(Orcania_DIR "${CMAKE_CURRENT_LIST_DIR}/../install/orcania/lib/cmake/Orcania")
set(MHD_LIBRARY "${CMAKE_CURRENT_LIST_DIR}/../extra/libmicrohttpd-1.0.1-w32-bin/x86_64/MinGW/static/mingw64/lib/libmicrohttpd.a")
set(MHD_INCLUDE_DIR "${CMAKE_CURRENT_LIST_DIR}/../extra/libmicrohttpd-1.0.1-w32-bin/x86_64/MinGW/static/mingw64/include")
add_subdirectory(../extra/ulfius ulfius)

target_link_libraries(ulfius PRIVATE ws2_32)
target_link_libraries(app PRIVATE ulfius_static)

Additionally, without any "external" linking, I was able to have success adding the following line into the Ulfius CMakeLists.txt:

if(WIN32 AND MINGW)
    LIST(APPEND ULFIUS_LIBS ws2_32)
endif()

I imagined this would be something y'all would have already tried though, so maybe you are missing the ws2_32 library in your toolchain also? For what it's worth, I am using a copy of GCC and associated files included with Strawberry Perl...

I opened PR #281 in case this addresses your issue. Please provide feedback if it does.

[pmcgaugh]

After some more time, I have the library compiling and running without crashing (although I have not been able to test out the actual library functionality). Please note, I am statically linking, so there might be changes to these steps for using the DLL.

First I went with a more traditional MSYS setup, here are my steps to configure things from scratch:

1. Install MSYS2 and run the UCRT64 executable from that environment (I used the default install path)
2. Run the following installs:

pacman -S mingw-w64-ucrt-x86_64-gcc
pacman -S mingw-w64-ucrt-x86_64-libmicrohttpd
pacman -S mingw-w64-ucrt-x86_64-curl
pacman -S mingw-w64-ucrt-x86_64-jansson

3. Build and Install the orcania library (this should be autodetected after install):

cmake -G Ninja -DCMAKE_C_COMPILER=C:/msys64/ucrt64/bin/gcc.exe -DCMAKE_CXX_COMPILER=C:/msys64/ucrt64/bin/g++.exe -DBUILD_STATIC=ON -DBUILD_BASE64URL=OFF -DCMAKE_INSTALL_PREFIX=C:/msys64/ucrt64/ -B build_orcania YOUR_ORCANIA_SRC_PATH
cmake --build ./build_orcania
cmake --install ./build_orcania

4. Update your Application CMakeLists.txt to build in ulfius:

option(BUILD_STATIC "..." ON)
option(BUILD_SHARED "..." OFF)
option(WITH_YDER "..." OFF)
option(BUILD_UWSC "..." OFF)
add_subdirectory(YOUR_ULFIUS_SRC_PATH ulfius)
target_link_libraries(app PRIVATE ulfius_static)
target_link_libraries(app PRIVATE ${MHD_LIBRARY})
target_link_libraries(app PRIVATE ws2_32)

This worked for me, although I haven't tested the protocol interface, it compiles and runs without crashing. I will update this message as I make further progress. I might build in YDER as well and will share progress confirming functionality.