[client] app: free overlays after display server shutdown

The render thread freed the overlays as soon as it exited, while the
main thread could still be dispatching display server input callbacks
that iterate them. Free the overlays in lg_shutdown instead, once the
render thread has been joined and the display server has shut down.

The overlays now outlive the renderer, so overlayFreeImage must not
call into it; renderer deinitialization has already destroyed all
textures along with the context.

client/src/app.c

@@ -858,6 +858,8 @@ void app_registerOverlay(const struct LG_OverlayOps * ops, const void * params)
     ops->earlyInit();
 }
 
+static bool l_overlaysInitialized = false;
+
 void app_initOverlays(void)
 {
   struct Overlay * overlay;
@@ -868,9 +870,12 @@ void app_initOverlays(void)
     if (!overlay->ops->init(&overlay->udata, overlay->params))
     {
       DEBUG_ERROR("Overlay `%s` failed to initialize", overlay->ops->name);
-      overlay->ops = NULL;
+      ll_removeNL(g_state.overlays, item);
+      free(item);
+      free(overlay);
     }
   }
+  l_overlaysInitialized = true;
   ll_unlock(g_state.overlays);
 
   /* Do not seed ImGui's clock with absolute host uptime. ImGui stores the
@@ -1066,9 +1071,11 @@ void app_freeOverlays(void)
   struct Overlay * overlay;
   while(ll_shift(g_state.overlays, (void **)&overlay))
   {
-    overlay->ops->free(overlay->udata);
+    if (l_overlaysInitialized)
+      overlay->ops->free(overlay->udata);
     free(overlay);
   }
+  l_overlaysInitialized = false;
 }
 
 void app_setOverlay(bool enable)

client/src/main.c

@@ -1078,13 +1078,6 @@ static int renderThread(void * unused)
 
   app_setState(APP_STATE_SHUTDOWN);
 
-  if (g_state.overlays)
-  {
-    app_freeOverlays();
-    ll_free(g_state.overlays);
-    g_state.overlays = NULL;
-  }
-
   lgTimerDestroy(tickTimer);
   lgTimerDestroy(fpsTimer);
 
@@ -3505,6 +3498,9 @@ static void lg_shutdown(void)
   }
   LG_LOCK_FREE(l_cursorRepaint.lock);
 
+  // An evdev batch may call input handlers; join before input teardown
+  evdev_stop();
+
   if (g_state.transport.ops)
   {
     lgInput_dropTransport();
@@ -3540,6 +3536,7 @@ static void lg_shutdown(void)
 
   if (g_state.ds)
     g_state.ds->shutdown();
+
   lgClipboard_free();
 
   app_releaseAllKeybinds();
@@ -3548,6 +3545,16 @@ static void lg_shutdown(void)
   if (g_state.ds && g_state.dsInitialized)
     g_state.ds->free();
 
+  // Input callbacks have stopped; the evdev state and overlays can go
+  evdev_free();
+
+  if (g_state.overlays)
+  {
+    app_freeOverlays();
+    ll_free(g_state.overlays);
+    g_state.overlays = NULL;
+  }
+
   renderQueue_setSourceFns(NULL, NULL, NULL);
   renderQueue_free();
   LG_LOCK_FREE(g_state.videoSourceLock);

client/src/overlay_utils.c

@@ -182,5 +182,9 @@ void overlayFreeImage(OverlayImage * image)
   if (!image->tex)
     return;
 
-  RENDERER(freeTexture, image->tex);
+  // During shutdown the renderer is freed first, taking all textures with it
+  if (g_state.lgr)
+    RENDERER(freeTexture, image->tex);
+
+  image->tex = NULL;
 }