Change the way modules are destroyed;

They are now destroyed explicitly after tearing down the Lua state
instead of relying on finalizers.  It's definitely annoying to make it
coordinated in a centralized way like this instead of being distributed,
but there's not really any reliabel way to ensure that graphics objects
are destroyed before the graphics module/device is destroyed, which is a
problem.

src/api/api.c

@@ -28,6 +28,17 @@ LOVR_EXPORT int luaopen_lovr_system(lua_State* L);
 LOVR_EXPORT int luaopen_lovr_thread(lua_State* L);
 LOVR_EXPORT int luaopen_lovr_timer(lua_State* L);
 
+void lovrAudioDestroy(void);
+void lovrEventDestroy(void);
+void lovrFilesystemDestroy(void);
+void lovrGraphicsDestroy(void);
+void lovrHeadsetDestroy(void);
+void lovrMathDestroy(void);
+void lovrPhysicsDestroy(void);
+void lovrSystemDestroy(void);
+void lovrThreadModuleDestroy(void);
+void lovrTimerDestroy(void);
+
 // Object names are lightuserdata because Variants need a non-Lua string due to threads.
 static int luax_meta__tostring(lua_State* L) {
   lua_getfield(L, -1, "__info");
@@ -116,6 +127,40 @@ void luax_preload(lua_State* L) {
   lua_pop(L, 2);
 }
 
+// Destroys modules in a specific order
+void luax_unload(lua_State* L) {
+#ifndef LOVR_DISABLE_TIMER
+  lovrTimerDestroy();
+#endif
+#ifndef LOVR_DISABLE_MATH
+  lovrMathDestroy();
+#endif
+#ifndef LOVR_DISABLE_EVENT
+  lovrEventDestroy();
+#endif
+#ifndef LOVR_DISABLE_THREAD
+  lovrThreadModuleDestroy();
+#endif
+#ifndef LOVR_DISABLE_PHYSICS
+  lovrPhysicsDestroy();
+#endif
+#ifndef LOVR_DISABLE_AUDIO
+  lovrAudioDestroy();
+#endif
+#ifndef LOVR_DISABLE_HEADSET
+  lovrHeadsetDestroy();
+#endif
+#ifndef LOVR_DISABLE_GRAPHICS
+  lovrGraphicsDestroy();
+#endif
+#ifndef LOVR_DISABLE_SYSTEM
+  lovrSystemDestroy();
+#endif
+#ifndef LOVR_DISABLE_FILESYSTEM
+  lovrFilesystemDestroy();
+#endif
+}
+
 void _luax_registertype(lua_State* L, const char* name, const luaL_Reg* functions, destructorFn* destructor) {
 
   // Push metatable

src/api/api.h

@@ -111,6 +111,7 @@ typedef struct {
 #define luax_clearerror(L) lua_pushnil(L), luax_seterror(L)
 
 void luax_preload(struct lua_State* L);
+void luax_unload(struct lua_State* L);
 void _luax_registertype(struct lua_State* L, const char* name, const struct luaL_Reg* functions, void (*destructor)(void*));
 void* _luax_totype(struct lua_State* L, int index, uint64_t hash);
 void* _luax_checktype(struct lua_State* L, int index, uint64_t hash, const char* debug);

src/api/l_audio.c

@@ -331,7 +331,6 @@ int luaopen_lovr_audio(lua_State* L) {
   lua_pop(L, 1);
 
   if (lovrAudioInit(spatializer, sampleRate)) {
-    luax_atexit(L, lovrAudioDestroy);
     if (start) {
       lovrAudioSetDevice(AUDIO_PLAYBACK, NULL, 0, NULL, AUDIO_SHARED);
       lovrAudioStart(AUDIO_PLAYBACK);

src/api/l_event.c

@@ -214,9 +214,6 @@ int luaopen_lovr_event(lua_State* L) {
   lua_pushcfunction(L, nextEvent);
   pollRef = luaL_ref(L, LUA_REGISTRYINDEX);
 
-  if (lovrEventInit()) {
-    luax_atexit(L, lovrEventDestroy);
-  }
-
+  lovrEventInit();
   return 1;
 }

src/api/l_filesystem.c

@@ -516,9 +516,7 @@ int luaopen_lovr_filesystem(lua_State* L) {
   }
   lua_pop(L, 1);
 
-  if (lovrFilesystemInit(archive)) {
-    luax_atexit(L, lovrFilesystemDestroy);
-  }
+  lovrFilesystemInit(archive);
 
   lua_newtable(L);
   luax_register(L, lovrFilesystem);

src/api/l_graphics.c

@@ -658,17 +658,10 @@ static int l_lovrGraphicsInit(lua_State* L) {
 
   if (shaderCache) {
     config.cacheData = luax_readfile(".lovrshadercache", &config.cacheSize);
+    luax_atexit(L, luax_writeshadercache);
   }
 
-  if (lovrGraphicsInit(&config)) {
-    luax_atexit(L, lovrGraphicsDestroy);
-
-    // Finalizers run in the opposite order they were added, so this has to go last
-    if (shaderCache) {
-      luax_atexit(L, luax_writeshadercache);
-    }
-  }
-
+  lovrGraphicsInit(&config);
   return 0;
 }
 

src/api/l_headset.c

@@ -672,7 +672,6 @@ int luaopen_lovr_headset(lua_State* L) {
   }
   lua_pop(L, 1);
 
-  luax_atexit(L, lovrHeadsetDestroy);
   lovrHeadsetInit(&config);
   return 1;
 }

src/api/l_math.c

@@ -389,9 +389,7 @@ int luaopen_lovr_math(lua_State* L) {
   lua_pop(L, 1);
 
   // Module
-  if (lovrMathInit()) {
-    luax_atexit(L, lovrMathDestroy);
-  }
+  lovrMathInit();
 
   // Each Lua state gets its own thread-local Pool
   pool = lovrPoolCreate();

src/api/l_physics.c

@@ -169,8 +169,6 @@ int luaopen_lovr_physics(lua_State* L) {
   luax_registertype(L, CapsuleShape);
   luax_registertype(L, CylinderShape);
   luax_registertype(L, MeshShape);
-  if (lovrPhysicsInit()) {
-    luax_atexit(L, lovrPhysicsDestroy);
-  }
+  lovrPhysicsInit();
   return 1;
 }

src/api/l_system.c

@@ -205,8 +205,6 @@ static const luaL_Reg lovrSystem[] = {
 int luaopen_lovr_system(lua_State* L) {
   lua_newtable(L);
   luax_register(L, lovrSystem);
-  if (lovrSystemInit()) {
-    luax_atexit(L, lovrSystemDestroy);
-  }
+  lovrSystemInit();
   return 1;
 }

src/api/l_thread.c

@@ -110,8 +110,6 @@ int luaopen_lovr_thread(lua_State* L) {
   luax_register(L, lovrThreadModule);
   luax_registertype(L, Thread);
   luax_registertype(L, Channel);
-  if (lovrThreadModuleInit()) {
-    luax_atexit(L, lovrThreadModuleDestroy);
-  }
+  lovrThreadModuleInit();
   return 1;
 }

src/api/l_timer.c

@@ -47,8 +47,7 @@ static const luaL_Reg lovrTimer[] = {
 int luaopen_lovr_timer(lua_State* L) {
   lua_newtable(L);
   luax_register(L, lovrTimer);
-  if (lovrTimerInit()) {
-    luax_atexit(L, lovrTimerDestroy);
-  }
+  lovrTimerInit();
+  luax_atexit(L, lovrTimerDestroy);
   return 1;
 }

src/main.c

@@ -132,6 +132,7 @@ int main(int argc, char** argv) {
       memset(&cookie.value, 0, sizeof(cookie.value));
     }
     lua_close(L);
+    luax_unload(L);
   } while (restart);
 
   os_destroy();
@@ -147,6 +148,7 @@ void lovrDestroy(void* arg) {
     lua_State* L = context->L;
     emscripten_cancel_main_loop();
     lua_close(L);
+    luax_unload(L);
     os_destroy();
   }
 }
@@ -165,6 +167,7 @@ static void emscriptenLoop(void* arg) {
     }
 
     lua_close(context->L);
+    luax_unload(L);
     emscripten_cancel_main_loop();
 
     if (restart) {