build lanchdf with steam sdk

.gitignore

@@ -80,3 +80,6 @@ tags
 
 # external plugins
 /plugins/CMakeLists.custom.txt
+
+# steam api
+depends/steam

CMakeLists.txt

@@ -312,6 +312,19 @@ if(WIN32)
             ${SDLREAL_DOWNLOAD_DIR}/SDLreal.dll
             "5a09604daca6b2b5ce049d79af935d6a")
     endif()
+
+    # download Steam SDK
+    set (STEAMAPI_DIR ${dfhack_SOURCE_DIR}/depends/steam/)
+    download_file("https://partner.steamgames.com/downloads/steamworks_sdk_156.zip"
+            ${STEAMAPI_DIR}/steamworks_sdk_156.zip
+            "af5a579990dbe5ae4c1b0689260d001b")
+    file(ARCHIVE_EXTRACT
+            INPUT ${STEAMAPI_DIR}/steamworks_sdk_156.zip
+            DESTINATION ${STEAMAPI_DIR})
+    set(STEAMAPI_LIBRARY "${STEAMAPI_DIR}/sdk/redistributable_bin/win64/steam_api64.lib")
+    set(STEAMAPI_SOURCE_DIR "${STEAMAPI_DIR}/sdk/public/steam")
+    set(STEAMAPI_SHARED_LIBRARY "${STEAMAPI_DIR}/sdk/redistributable_bin/win64/steam_api64.dll")
+
 endif()
 
 if(APPLE)

package/windows/CMakeLists.txt

@@ -1,7 +1,9 @@
 project(package_windows)
 
 if(WIN32)
-    add_executable(launchdf WIN32 launchdf.c)
-    install(TARGETS launchdf
-        DESTINATION ${DFHACK_DATA_DESTINATION})
+    include_directories(${STEAMAPI_SOURCE_DIR})
+    link_libraries(${STEAMAPI_LIBRARY})
+    add_executable(launchdf WIN32 launchdf.cpp)
+    install(TARGETS launchdf DESTINATION ${DFHACK_DATA_DESTINATION})
+    install(FILES ${STEAMAPI_SHARED_LIBRARY} DESTINATION ${DFHACK_DATA_DESTINATION})
 endif()

package/windows/launchdf.cpp

@@ -1,13 +1,17 @@
 #include <process.h>
 #include <windows.h>
+#include "steam_api.h"
+
+const uint32 DFHACK_STEAM_APPID = 2346660;
 
 static BOOL is_running_on_wine() {
-    static const char *(CDECL *pwine_get_version)(void);
+    typedef const char* (CDECL wine_get_version)(void);
+    static wine_get_version* pwine_get_version;
     HMODULE hntdll = GetModuleHandle("ntdll.dll");
     if(!hntdll)
         return FALSE;
 
-    pwine_get_version = (void *)GetProcAddress(hntdll, "wine_get_version");
+    pwine_get_version = (wine_get_version*) GetProcAddress(hntdll, "wine_get_version");
     return !!pwine_get_version;
 }
 
@@ -61,6 +65,20 @@ static BOOL launch_direct() {
 }
 
 int WINAPI wWinMain(HINSTANCE hi, HINSTANCE hpi, PWSTR cmd, int ns) {
+
+    if (SteamAPI_RestartAppIfNecessary(DFHACK_STEAM_APPID)) // Replace with your App ID
+    {
+        return 1;
+    }
+
+        if (!SteamAPI_Init())
+        {
+            printf("Fatal Error - Steam must be running to play this game (SteamAPI_Init() failed).\n");
+            return 1;
+        }
+
+        return 0;
+
     LPCWSTR err =  is_running_on_wine() ? launch_via_steam_posix() : launch_via_steam_windows();
 
     if (err && !launch_direct()) {