使用 CMake 在 Windows 10 上构建 uWebSockets

Question

I want to use uWebSockets (UWS) in my C++ project to transfer images over the network. The setup will be running on multiple operating systems, so the best way of creating the build files seemed like using CMake.

However, I am new to CMake and having a hard time building UWS. I don't understand how to start working with the official repository on Windows 10, so I found another repository that includes a CMakeFiles.txt file and some of the dependencies ( openssl, zlib, libuv , but it doesn't include uSockets for some reason). The root CMakeFiles.txt includes:

[...] 

find_package(OpenSSL REQUIRED)
find_package(ZLIB REQUIRED)

find_path(LIBUV_INCLUDE_DIR uv.h)
find_library(LIBUV_LIBRARY NAMES uv uv1)

[...] 

It looks straightforward, but when I try to run mkdir build && cd build; cmake .. mkdir build && cd build; cmake .. , it cannot find OpenSSL . Here is the error message it spits out:

[...]
[cmake]   Could not find a package configuration file provided by "OpenSSL" with any
[cmake]   of the following names:
[cmake] 
[cmake]     OpenSSLConfig.cmake
[cmake]     openssl-config.cmake
[...]

The above error message suggests that I need to set up a config file for each of these libraries. Yet, if I understand the find_package docs correctly, the command itself searches the library in various locations under the root folder. What kind of a folder structure does the find_package need in order to work?

More generally, am I wasting my time with this alternative repo? Is there a better way of using UWS with Windows 10? The official repo has a question about how to use it on Windows but I don't understand how that's an answer to the question. It only points to this page where it says any specific build systems will not officially be supported.

Any help would be appreciated.

Answer 1

Importing dependencies with add_subdirectory seems like a good way around this. When I ran cmake, I was receiving LNK2019 Error. I realized the following code snippet I found online was causing the problem, and the system works when I delete it.

if(MSVC)
    set(CMAKE_EXE_LINKER_FLAGS_DEBUG "${CMAKE_EXE_LINKER_FLAGS_DEBUG} /NODEFAULTLIB:libcmt.lib /NODEFAULTLIB:msvcrt.lib")
    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /SUBSYSTEM:WINDOWS")
endif()