caulk is an up-to-date, functional, NON-DEPRECATED wrapper for Valve's Steamworks API for use with plain C. Capische?
Refer to the usage section and the code example for a quick rundown.
✔️ Schwungus-certified.
The Steamworks SDK provides the header steam_api_flat.h which declares interoperable interface functions. However, it isn't pure C, leading to build errors (duh). This library mitigates that by generating a plain-C compatibility layer to C++ types, functions, and methods defined in the SDK, with the help of steam_api.json.
caulk requires a ZIP of the Steamworks SDK in your project's root. Click that link to semi-legally download it.
caulk uses CMake for the build pipeline. Since CMake is the de-facto standard for cross-platform C/C++ compilation, you shouldn't be afraid to use it - here's a CMakeLists.txt example:
cmake_minimum_required(VERSION 3.24.0 FATAL_ERROR)
project(myProject)
# REQUIRED: point this to your Steamworks SDK archive.
set(STEAMWORKS_SDK_ZIP ${CMAKE_SOURCE_DIR}/steamworks_sdk_162.zip)
include(FetchContent)
FetchContent_Declare(
caulk
GIT_REPOSITORY "https://github.com/Schwungus/caulk.git"
GIT_TAG <release tag or commit SHA>) # edit this line to your liking
FetchContent_MakeAvailable(caulk)
add_executable(myProject main.c)
caulk_register(myProject) # automatic copying of steam_appid.txt and shared library objectsYou'll also need to include a steam_appid.txt in your project's root; caulk_register copies that over as well.
To use the Steam API from your C code, add #include "caulk.h" and prefix each SteamAPI function with caulk_:
#include <stdlib.h>
#include "caulk.h"
int main(int argc, char* argv[]) {
if (!caulk_Init())
return EXIT_FAILURE;
/* Do SteamAPI stuff here... */
caulk_Shutdown();
return EXIT_SUCCESS;
}Again, see test.c for a more complete example.
The Steamworks API relies a lot on callbacks and call results. Here's how to use them.
If a method returns SteamAPICall_t instead of giving you the desired result, it must be an asynchronous call which will spit out a value eventually. To use said value, you'll have to define a handler function using caulk_Resolve(), which is called by caulk_Dispatch() whenever your result is ready.
Also, you'll be receiving a lot of events from Steamworks. To make any use of them, you'll have to register handlers using caulk_Register().
See the example below for both caulk_Resolve() and caulk_Register():
#include <stdlib.h>
#include "caulk.h"
static void resolveCreateLobby(void* pData, bool ioFail) {
LobbyCreated_t* data = pData;
if (!ioFail && data->m_eResult == k_EResultOK)
printf("Created lobby ID=%d!!!\n", data->m_ulSteamIDLobby);
}
static void onEnterLobby(void* pData) {
LobbyEnter_t* data = pData;
// Do cool stuff with `data`.
}
int main(int argc, char* argv[]) {
if (!caulk_Init())
return EXIT_FAILURE;
// Call `onEnterLobby()` every time we enter a lobby.
caulk_Register(LobbyEnter_t_iCallback, onEnterLobby);
// Let a lobby be created in the background, and run `resolveCreateLobby()` when it's done.
SteamAPICall_t cb = caulk_ISteamMatchmaking_CreateLobby(mm, k_ELobbyTypeFriendsOnly, 2);
caulk_Resolve(cb, resolveCreateLobby);
for (;;)
// Dispatch the registered handlers:
caulk_Dispatch(); // should put a `Sleep` here or smth...
caulk_Shutdown();
return EXIT_SUCCESS;
}