--- lbbs/src/menu.c	2025/05/19 06:26:07	1.51
+++ lbbs/src/menu.c	2025/05/23 13:32:51	1.55
@@ -951,7 +951,12 @@ int display_menu(MENU_SET *p_menu_set)
 	if (p_menu == NULL)
 	{
 		log_error("get_menu_by_id(%d) return NULL pointer\n", menu_id);
-		return -1;
+		if (p_menu_set->choose_step > 0)
+		{
+			p_menu_set->choose_step--;
+			return REDRAW;
+		}
+		return EXITBBS;
 	}
 
 	menu_item_pos = p_menu_set->menu_item_pos[p_menu_set->choose_step];
@@ -960,7 +965,7 @@ int display_menu(MENU_SET *p_menu_set)
 	if (p_menu_item == NULL)
 	{
 		log_error("get_menu_item_by_id(%d) return NULL pointer\n", menu_item_id);
-		return -1;
+		menu_item_pos = 0;
 	}
 
 	if (menu_item_pos > 0 &&
@@ -1020,10 +1025,14 @@ int display_menu(MENU_SET *p_menu_set)
 
 	if (!menu_selectable)
 	{
+		log_error("No selectable menu item in current menu (%s)\n", p_menu->name);
 		return -1;
 	}
 
-	display_menu_current_page(p_menu_set);
+	if (display_menu_current_page(p_menu_set) != 0)
+	{
+		return -1;
+	}
 
 	display_menu_cursor(p_menu_set, 1);
 
@@ -1042,7 +1051,8 @@ int menu_control(MENU_SET *p_menu_set, i
 
 	if (p_menu_set->menu_count == 0)
 	{
-		return 0;
+		log_error("Empty menu set\n");
+		return EXITBBS;
 	}
 
 	menu_id = p_menu_set->menu_id_path[p_menu_set->choose_step];
@@ -1050,12 +1060,23 @@ int menu_control(MENU_SET *p_menu_set, i
 	if (p_menu == NULL)
 	{
 		log_error("get_menu_by_id(%d) return NULL pointer\n", menu_id);
-		return -1;
+		if (p_menu_set->choose_step > 0)
+		{
+			p_menu_set->choose_step--;
+			return REDRAW;
+		}
+		return EXITBBS;
 	}
 
 	if (p_menu->item_count == 0)
 	{
-		return 0;
+		log_error("Empty menu (%s)\n", p_menu->name);
+		if (p_menu_set->choose_step > 0)
+		{
+			p_menu_set->choose_step--;
+			return REDRAW;
+		}
+		return EXITBBS;
 	}
 
 	menu_item_pos = p_menu_set->menu_item_pos[p_menu_set->choose_step];
@@ -1066,7 +1087,8 @@ int menu_control(MENU_SET *p_menu_set, i
 	if (p_menu_item == NULL)
 	{
 		log_error("get_menu_item_by_id(%d) return NULL pointer\n", menu_item_id);
-		return -1;
+		p_menu_set->menu_item_pos[p_menu_set->choose_step] = 0;
+		return REDRAW;
 	}
 
 	switch (key)
@@ -1098,14 +1120,14 @@ int menu_control(MENU_SET *p_menu_set, i
 		if (p_menu_set->choose_step > 0)
 		{
 			p_menu_set->choose_step--;
-			if (display_menu(p_menu_set) != 0)
-			{
-				return menu_control(p_menu_set, KEY_LEFT);
-			}
 			if (p_menu_set->choose_step == 0)
 			{
 				return REDRAW;
 			}
+			if (display_menu(p_menu_set) != 0)
+			{
+				return menu_control(p_menu_set, KEY_LEFT);
+			}
 		}
 		else
 		{
@@ -1309,33 +1331,17 @@ int unload_menu(MENU_SET *p_menu_set)
 
 int load_menu_shm(MENU_SET *p_menu_set)
 {
-	// Mount shared memory
-	if (p_menu_set->p_reserved == NULL)
+	void *p_shm;
+
+	// Remap shared memory in read-only mode
+	p_shm = shmat(p_menu_set->shmid, p_menu_set->p_reserved, SHM_RDONLY | SHM_REMAP);
+	if (p_shm == (void *)-1)
 	{
-		p_menu_set->p_reserved = shmat(p_menu_set->shmid, NULL, SHM_RDONLY);
-		if (p_menu_set->p_reserved == (void *)-1)
-		{
-			log_error("shmat() error (%d)\n", errno);
-			return -1;
-		}
+		log_error("shmat() error (%d)\n", errno);
+		return -1;
 	}
-
-	p_menu_set->p_menu_pool = p_menu_set->p_reserved + MENU_SET_RESERVED_LENGTH;
-	p_menu_set->p_menu_item_pool = p_menu_set->p_menu_pool + sizeof(MENU) * MAX_MENUS;
-	p_menu_set->p_menu_screen_pool = p_menu_set->p_menu_item_pool + sizeof(MENU_ITEM) * MAX_MENUITEMS;
-	p_menu_set->p_menu_screen_buf = p_menu_set->p_menu_screen_pool + sizeof(MENU_SCREEN) * MAX_MENUS;
-	p_menu_set->p_menu_screen_buf_free = p_menu_set->p_menu_screen_buf;
-
-	// Restore status varaibles into reserved memory area
-	p_menu_set->menu_count = *((int16_t *)p_menu_set->p_reserved);
-	p_menu_set->menu_item_count = *(((int16_t *)p_menu_set->p_reserved) + 1);
-	p_menu_set->menu_screen_count = *(((int16_t *)p_menu_set->p_reserved) + 2);
-
-	p_menu_set->choose_step = 0;
-	p_menu_set->menu_id_path[0] = 0;
-
-	p_menu_set->p_menu_name_dict = NULL;
-	p_menu_set->p_menu_screen_dict = NULL;
+	
+	p_menu_set->p_reserved = p_shm;
 
 	return 0;
 }
@@ -1360,5 +1366,17 @@ int unload_menu_shm(MENU_SET *p_menu_set
 	}
 	p_menu_set->p_reserved = NULL;
 
+	if (p_menu_set->p_menu_name_dict != NULL)
+	{
+		trie_dict_destroy(p_menu_set->p_menu_name_dict);
+		p_menu_set->p_menu_name_dict = NULL;
+	}
+
+	if (p_menu_set->p_menu_screen_dict != NULL)
+	{
+		trie_dict_destroy(p_menu_set->p_menu_screen_dict);
+		p_menu_set->p_menu_screen_dict = NULL;
+	}
+
 	return 0;
 }