change Core's lifecycle

library/Console-windows.cpp

@@ -516,6 +516,7 @@ bool Console::init(bool)
 // FIXME: looks awfully empty, doesn't it?
 bool Console::shutdown(void)
 {
+    assert(inited);
     std::lock_guard<std::recursive_mutex> lock{*wlock};
     FreeConsole();
     inited = false;

library/Core.cpp

@@ -127,6 +127,8 @@ namespace DFHack {
         return Core::getInstance().getHackPath() / "data" / "dfhack-config-defaults";
     };
 
+    Core* Core::active_instance = nullptr;
+
 class MainThread {
 public:
     //! MainThread::suspend keeps the main DF thread suspended from Core::Init to
@@ -1077,6 +1079,11 @@ df::viewscreen * Core::getTopViewscreen() {
 }
 
 bool Core::InitMainThread(std::filesystem::path path) {
+    assert(active_instance == nullptr);
+
+    // set this instance as the active instance
+    active_instance = this;
+
     // this hook is always called from DF's main (render) thread, so capture this thread id
     df_render_thread = std::this_thread::get_id();
     hack_path = path;
@@ -1490,8 +1497,8 @@ bool Core::InitSimulationThread()
 }
 
 Core& Core::getInstance() {
-    static Core instance;
-    return instance;
+    assert(Core::active_instance != nullptr);
+    return *Core::active_instance;
 }
 
 bool Core::isSuspended(void)
@@ -1921,20 +1928,27 @@ int Core::Shutdown ( void )
 
     if (hotkey_mgr) {
         delete hotkey_mgr;
+        hotkey_mgr = nullptr;
     }
 
     if(plug_mgr)
     {
         delete plug_mgr;
         plug_mgr = nullptr;
     }
+
     // invalidate all modules
     allModules.clear();
     Textures::cleanup();
     DFSDL::cleanup();
-    DFSteam::cleanup(getConsole());
+    DFSteam::cleanup();
+
     memset(&(s_mods), 0, sizeof(s_mods));
     d.reset();
+
+    // clear active instance
+    Core::active_instance = nullptr;
+
     return -1;
 }
 

library/Debug.cpp

@@ -66,9 +66,6 @@ void DebugManager::unregisterCategory(DebugCategory& cat)
 
 DebugRegisterBase::DebugRegisterBase(DebugCategory* cat)
 {
-    // Make sure Core lives at least as long any DebugCategory to
-    // allow debug prints until all Debugcategories has been destructed
-    Core::getInstance();
     DebugManager::getInstance().registerCategory(*cat);
 }
 

library/Hooks.cpp

@@ -40,6 +40,8 @@ DFhackCExport void dfhooks_preinit(std::filesystem::path dllpath)
     basepath = dllpath.parent_path();
 }
 
+static std::unique_ptr<DFHack::Core> core_instance;
+
 // called from the main thread before the simulation thread is started
 // and the main event loop is initiated
 DFhackCExport void dfhooks_init() {
@@ -49,8 +51,11 @@ DFhackCExport void dfhooks_init() {
         return;
     }
 
+    // construct DFHack core instance
+    core_instance = std::make_unique<DFHack::Core>();
+
     // we need to init DF globals before we can check the commandline
-    if (!DFHack::Core::getInstance().InitMainThread(std::filesystem::canonical(basepath)) || !df::global::game) {
+    if (!core_instance->InitMainThread(std::filesystem::canonical(basepath)) || !df::global::game) {
         // we don't set disabled to true here so symbol generation can work
         return;
     }
@@ -59,6 +64,8 @@ DFhackCExport void dfhooks_init() {
     if (cmdline.find("--disable-dfhack") != std::string::npos) {
         fprintf(stderr, "dfhack: --disable-dfhack specified on commandline; disabling\n");
         disabled = true;
+        core_instance->Shutdown();
+        core_instance.reset();
         return;
     }
 
@@ -69,14 +76,16 @@ DFhackCExport void dfhooks_init() {
 DFhackCExport void dfhooks_shutdown() {
     if (disabled)
         return;
-    DFHack::Core::getInstance().Shutdown();
+    core_instance->Shutdown();
+    // release DFHack core instance
+    core_instance.reset();
 }
 
 // called from the simulation thread in the main event loop
 DFhackCExport void dfhooks_update() {
     if (disabled)
         return;
-    DFHack::Core::getInstance().Update();
+    core_instance->Update();
 }
 
 // called from the simulation thread just before adding the macro
@@ -92,7 +101,7 @@ DFhackCExport void dfhooks_prerender() {
 DFhackCExport bool dfhooks_sdl_event(SDL_Event* event) {
     if (disabled)
         return false;
-    return DFHack::Core::getInstance().DFH_SDL_Event(event);
+    return core_instance->DFH_SDL_Event(event);
 }
 
 // called from the main thread just after setting mouse state in gps and just
@@ -101,7 +110,7 @@ DFhackCExport void dfhooks_sdl_loop() {
     if (disabled)
         return;
     // TODO: wire this up to the new SDL-based console once it is merged
-    DFHack::Core::getInstance().DFH_SDL_Loop();
+    core_instance->DFH_SDL_Loop();
 }
 
 // called from the main thread for each utf-8 char read from the ncurses input
@@ -111,5 +120,5 @@ DFhackCExport void dfhooks_sdl_loop() {
 DFhackCExport bool dfhooks_ncurses_key(int key) {
     if (disabled)
         return false;
-    return DFHack::Core::getInstance().DFH_ncurses_key(key);
+    return core_instance->DFH_ncurses_key(key);
 }

library/include/Core.h

@@ -157,8 +157,11 @@ namespace DFHack
         friend void ::dfhooks_sdl_loop();
         friend bool ::dfhooks_ncurses_key(int key);
     public:
-        /// Get the single Core instance or make one.
+        /// Get the current active Core instance. will assert if none exists
+        /// Use noInstance() to check first if unsure
         static Core& getInstance();
+        static bool noInstance() { return active_instance == nullptr; }
+
         /// check if the activity lock is owned by this thread
         bool isSuspended(void);
         /// Is everything OK?
@@ -259,11 +262,14 @@ namespace DFHack
             return false;
         }
 
+        Core();
+        ~Core();
+
     private:
+        static Core* active_instance;
+
         DFHack::Console con;
 
-        Core();
-        ~Core();
 
         struct Private;
         std::unique_ptr<Private> d;

library/include/Debug.h

@@ -183,7 +183,7 @@ class DFHACK_EXPORT DebugCategory final {
     };
 
     /*!
-     * Fetch a steam object proxy object for output. It also adds standard
+     * Fetch a stream object proxy object for output. It also adds standard
      * message components like time and plugin and category names to the line.
      *
      * User must make sure that the line is terminated with a line end.
@@ -194,6 +194,13 @@ class DFHACK_EXPORT DebugCategory final {
      */
     ostream_proxy_prefix getStream(const level msgLevel) const
     {
+        // if the core instance is unavailable, use stderr as a fallback
+        if (Core::noInstance())
+        {
+            static color_ostream_wrapper fallback{std::cerr};
+            return {*this,fallback,msgLevel};
+        }
+
         return {*this,Core::getInstance().getConsole(),msgLevel};
     }
     /*!

library/include/modules/DFSteam.h

@@ -24,7 +24,7 @@ bool init(DFHack::color_ostream& out);
 /**
  * Call this when DFHack is being unloaded.
  */
-void cleanup(DFHack::color_ostream& out);
+void cleanup();
 
 DFHACK_EXPORT void launchSteamDFHackIfNecessary(DFHack::color_ostream& out);
 

library/modules/DFSteam.cpp

@@ -35,17 +35,20 @@ bool (*g_SteamAPI_RestartAppIfNecessary)(uint32_t unOwnAppID) = nullptr;
 void* (*g_SteamInternal_FindOrCreateUserInterface)(int, const char*) = nullptr;
 bool (*g_SteamAPI_ISteamApps_BIsAppInstalled)(void *iSteamApps, uint32_t appID) = nullptr;
 
-static void bind_all(color_ostream& out, DFLibrary* handle) {
-#define bind(name) \
-        if (!handle) { \
-            g_##name = nullptr; \
-        } else { \
-            g_##name = (decltype(g_##name))LookupPlugin(handle, #name); \
-            if (!g_##name) { \
-                WARN(dfsteam, out).print("steam library function not found: " #name "\n"); \
-            } \
+template<typename Ptr>
+static void bind_(color_ostream& out, DFLibrary* handle, const char* name, Ptr& func_ptr) {
+    if (!handle) {
+        func_ptr = nullptr;
+    } else {
+        func_ptr = (Ptr)LookupPlugin(handle, name);
+        if (!func_ptr) {
+            WARN(dfsteam, out).print("steam library function not found: {}\n", name);
         }
+    }
+}
 
+static void bind_all(color_ostream& out, DFLibrary* handle) {
+#define bind(name) bind_(out, handle, #name, g_##name)
     bind(SteamAPI_Init);
     bind(SteamAPI_Shutdown);
     bind(SteamAPI_GetHSteamUser);
@@ -56,6 +59,16 @@ static void bind_all(color_ostream& out, DFLibrary* handle) {
 #undef bind
 }
 
+static void unbind_all()
+{
+    g_SteamAPI_Init = nullptr;
+    g_SteamAPI_Shutdown = nullptr;
+    g_SteamAPI_GetHSteamUser = nullptr;
+    g_SteamInternal_FindOrCreateUserInterface = nullptr;
+    g_SteamAPI_RestartAppIfNecessary = nullptr;
+    g_SteamAPI_ISteamApps_BIsAppInstalled = nullptr;
+}
+
 bool DFSteam::init(color_ostream& out) {
     char *steam_client_launch = getenv("SteamClientLaunch");
     if (!steam_client_launch || strncmp(steam_client_launch, "1", 2) != 0) {
@@ -84,7 +97,7 @@ bool DFSteam::init(color_ostream& out) {
     return true;
 }
 
-void DFSteam::cleanup(color_ostream& out) {
+void DFSteam::cleanup() {
     if (!g_steam_handle)
         return;
 
@@ -94,7 +107,7 @@ void DFSteam::cleanup(color_ostream& out) {
     ClosePlugin(g_steam_handle);
     g_steam_handle = nullptr;
 
-    bind_all(out, nullptr);
+    unbind_all();
     g_steam_initialized = false;
 }