tray: improved error checking

Also clean up any existing trays when the program quits

Fixes libsdl-org#11893

src/SDL.c

@@ -51,6 +51,7 @@
 #include "sensor/SDL_sensor_c.h"
 #include "stdlib/SDL_getenv_c.h"
 #include "thread/SDL_thread_c.h"
+#include "tray/SDL_tray_utils.h"
 #include "video/SDL_pixels_c.h"
 #include "video/SDL_surface_c.h"
 #include "video/SDL_video_c.h"
@@ -642,6 +643,7 @@ void SDL_Quit(void)
     SDL_HelperWindowDestroy();
 #endif
     SDL_QuitSubSystem(SDL_INIT_EVERYTHING);
+    SDL_CleanupTrays();
 
 #ifdef SDL_USE_LIBDBUS
     SDL_DBus_Quit();

src/SDL_utils.c

@@ -178,6 +178,22 @@ bool SDL_ObjectValid(void *object, SDL_ObjectType type)
     return (((SDL_ObjectType)(uintptr_t)object_type) == type);
 }
 
+int SDL_GetObjects(SDL_ObjectType type, void **objects, int count)
+{
+    const void *object, *object_type;
+    void *iter = NULL;
+    int num_objects = 0;
+    while (SDL_IterateHashTable(SDL_objects, &object, &object_type, &iter)) {
+        if ((SDL_ObjectType)(uintptr_t)object_type == type) {
+            if (num_objects < count) {
+                objects[num_objects] = (void *)object;
+            }
+            ++num_objects;
+        }
+    }
+    return num_objects;
+}
+
 void SDL_SetObjectsInvalid(void)
 {
     if (SDL_ShouldQuit(&SDL_objects_init)) {
@@ -217,6 +233,9 @@ void SDL_SetObjectsInvalid(void)
             case SDL_OBJECT_TYPE_THREAD:
                 type = "thread";
                 break;
+            case SDL_OBJECT_TYPE_TRAY:
+                type = "SDL_Tray";
+                break;
             default:
                 type = "unknown object";
                 break;

src/SDL_utils_c.h

@@ -61,12 +61,14 @@ typedef enum
     SDL_OBJECT_TYPE_HIDAPI_DEVICE,
     SDL_OBJECT_TYPE_HIDAPI_JOYSTICK,
     SDL_OBJECT_TYPE_THREAD,
+    SDL_OBJECT_TYPE_TRAY,
 
 } SDL_ObjectType;
 
 extern Uint32 SDL_GetNextObjectID(void);
 extern void SDL_SetObjectValid(void *object, SDL_ObjectType type, bool valid);
 extern bool SDL_ObjectValid(void *object, SDL_ObjectType type);
+extern int SDL_GetObjects(SDL_ObjectType type, void **objects, int count);
 extern void SDL_SetObjectsInvalid(void);
 
 extern const char *SDL_GetPersistentString(const char *string);

src/tray/SDL_tray_utils.c

@@ -27,38 +27,65 @@
 
 static int active_trays = 0;
 
-extern void SDL_IncrementTrayCount(void)
+void SDL_RegisterTray(SDL_Tray *tray)
 {
-    if (++active_trays < 1) {
-        SDL_Log("Active tray count corrupted (%d < 1), this is a bug. The app may close or fail to close unexpectedly.", active_trays);
-    }
+    SDL_SetObjectValid(tray, SDL_OBJECT_TYPE_TRAY, true);
+
+    ++active_trays;
 }
 
-extern void SDL_DecrementTrayCount(void)
+void SDL_UnregisterTray(SDL_Tray *tray)
 {
-    int toplevel_count = 0;
-    SDL_Window *n;
+    SDL_assert(SDL_ObjectValid(tray, SDL_OBJECT_TYPE_TRAY));
+
+    SDL_SetObjectValid(tray, SDL_OBJECT_TYPE_TRAY, false);
 
-    if (--active_trays < 0) {
-        SDL_Log("Active tray count corrupted (%d < 0), this is a bug. The app may close or fail to close unexpectedly.", active_trays);
+    --active_trays;
+    if (active_trays > 0) {
+        return;
     }
 
     if (!SDL_GetHintBoolean(SDL_HINT_QUIT_ON_LAST_WINDOW_CLOSE, true)) {
         return;
     }
 
-    for (n = SDL_GetVideoDevice()->windows; n; n = n->next) {
-        if (!n->parent && !(n->flags & SDL_WINDOW_HIDDEN)) {
-            ++toplevel_count;
+    int toplevel_count = 0;
+    SDL_Window **windows = SDL_GetWindows(NULL);
+    if (windows) {
+        for (int i = 0; windows[i]; ++i) {
+            SDL_Window *window = windows[i];
+            if (!window->parent && !(window->flags & SDL_WINDOW_HIDDEN)) {
+                ++toplevel_count;
+            }
         }
+        SDL_free(windows);
     }
 
-    if (toplevel_count < 1) {
+    if (toplevel_count == 0) {
         SDL_SendQuit();
     }
 }
 
-extern bool SDL_HasNoActiveTrays(void)
+void SDL_CleanupTrays(void)
+{
+    if (active_trays == 0) {
+        return;
+    }
+
+    void **trays = (void **)SDL_malloc(active_trays * sizeof(*trays));
+    if (!trays) {
+        return;
+    }
+
+    int count = SDL_GetObjects(SDL_OBJECT_TYPE_TRAY, trays, active_trays);
+    SDL_assert(count == active_trays);
+    for (int i = 0; i < count; ++i) {
+        SDL_DestroyTray((SDL_Tray *)trays[i]);
+    }
+    SDL_free(trays);
+}
+
+bool SDL_HasNoActiveTrays(void)
 {
-    return active_trays < 1;
+    return active_trays == 0;
 }

src/tray/SDL_tray_utils.h

@@ -20,6 +20,7 @@
 */
 #include "SDL_internal.h"
 
-extern void SDL_IncrementTrayCount(void);
-extern void SDL_DecrementTrayCount(void);
+extern void SDL_RegisterTray(SDL_Tray *tray);
+extern void SDL_UnregisterTray(SDL_Tray *tray);
+extern void SDL_CleanupTrays(void);
 extern bool SDL_HasNoActiveTrays(void);