Warn when scanning with no database present + indicate task failure with icon (#18359)

Author: zoltanvb

gfx/gfx_widgets.c

@@ -1290,7 +1290,8 @@ static void gfx_widgets_draw_task_msg(
          texture    = MENU_WIDGETS_ICON_ADD;
          color      = msg_queue_task_positive;
       }
-      else if (msg->flags & DISPWIDG_FLAG_NEGATIVE)
+      else if (   msg->flags & DISPWIDG_FLAG_NEGATIVE
+               || msg->flags & DISPWIDG_FLAG_TASK_ERROR)
       {
          texture    = MENU_WIDGETS_ICON_EXIT;
          color      = msg_queue_task_negative;

intl/msg_hash_us.h

@@ -15314,6 +15314,10 @@ MSG_HASH(
    MSG_SCANNING_OF_DIRECTORY_FINISHED,
    "Scanning of directory finished."
    )
+MSG_HASH(
+   MSG_SCANNING_NO_DATABASE,
+   "Scanning unsuccessful, no database found."
+   )
 MSG_HASH(
    MSG_SENDING_COMMAND,
    "Sending command"

msg_hash.h

@@ -507,6 +507,7 @@ enum msg_hash_enums
    MSG_SCANNING,
    MSG_SCANNING_OF_DIRECTORY_FINISHED,
    MSG_SCANNING_OF_FILE_FINISHED,
+   MSG_SCANNING_NO_DATABASE,
    MSG_LOADED_STATE_FROM_SLOT,
    MSG_LOADED_STATE_FROM_SLOT_AUTO,
    MSG_REMOVING_TEMPORARY_CONTENT_FILE,

tasks/task_database.c

@@ -1575,7 +1575,12 @@ static void task_database_handler(retro_task_t *task)
          else
          {
             const char *msg = NULL;
-            if (db->flags & DB_HANDLE_FLAG_IS_DIRECTORY)
+            if (dbstate->list->size == 0)
+            {
+               msg = msg_hash_to_str(MSG_SCANNING_NO_DATABASE);
+               task_set_error(task, strdup(msg));
+            }
+            else if (db->flags & DB_HANDLE_FLAG_IS_DIRECTORY)
                msg = msg_hash_to_str(MSG_SCANNING_OF_DIRECTORY_FINISHED);
             else
                msg = msg_hash_to_str(MSG_SCANNING_OF_FILE_FINISHED);