change Core's lifecycle

library/Console-windows.cpp

@@ -512,6 +512,7 @@ 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 Filesystem::getInstallDir() / "hack" / "data" / "dfhack-config-defaults";
     };
 
+    Core* Core::active_instance = nullptr;
+
 class MainThread {
 public:
     //! MainThread::suspend keeps the main DF thread suspended from Core::Init to
@@ -1062,6 +1064,11 @@ df::viewscreen * Core::getTopViewscreen() {
 }
 
 bool Core::InitMainThread() {
+    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();
 
@@ -1462,8 +1469,8 @@ bool Core::InitSimulationThread()
 }
 
 Core& Core::getInstance() {
-    static Core instance;
-    return instance;
+    assert(Core::active_instance != nullptr);
+    return *Core::active_instance;
 }
 
 bool Core::isSuspended(void)
@@ -1893,20 +1900,29 @@ 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();
+
+    // FIXME console has already been shut down at this point, so getConsole is returning a dead object
     DFSteam::cleanup(getConsole());
+
     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

@@ -7,6 +7,8 @@ static bool disabled = false;
 
 DFhackCExport const int32_t dfhooks_priority = 100;
 
+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() {
@@ -16,8 +18,11 @@ 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() || !df::global::game) {
+    if (!core_instance->InitMainThread() || !df::global::game) {
         // we don't set disabled to true here so symbol generation can work
         return;
     }
@@ -26,6 +31,8 @@ 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;
     }
 
@@ -36,14 +43,16 @@ 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
@@ -59,7 +68,7 @@ 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
@@ -68,7 +77,7 @@ 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
@@ -78,5 +87,5 @@ 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};
     }
     /*!