[PATCH 0/1] MR4676: server: Check whether the cursor has been set for a thread input.

[Rémi Bernon (＠rbernon)]

We are preferring the thread input cursor over the global desktop
cursor, but if the thread input has no cursor yet, for instance when
thread is attached to another thread without a message queue yet,
it will end up being invisible.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=55961

[PATCH 1/1] server: Check whether the cursor has been set for a thread input.

[Rémi Bernon]

From: Rémi Bernon

We are preferring the thread input cursor over the global desktop
cursor, but if the thread input has no cursor yet, for instance when
thread is attached to another thread without a message queue yet,
it will end up being invisible.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=55961
---
 server/queue.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/server/queue.c b/server/queue.c
index 0558bd111f9..ae34bb1819e 100644
--- a/server/queue.c
+++ b/server/queue.c
@@ -110,6 +110,7 @@ struct thread_input
     int                    caret_hide;    /* caret hide count */
     int                    caret_state;   /* caret on/off state */
     user_handle_t          cursor;        /* current cursor */
+    int                    has_cursor;    /* cursor has been set */
     int                    cursor_count;  /* cursor show count */
     struct list            msg_list;      /* list of hardware messages */
     unsigned char          keystate[256]; /* state of each key */
@@ -263,6 +264,7 @@ static struct thread_input *create_thread_input( struct thread *thread )
         input->menu_owner   = 0;
         input->move_size    = 0;
         input->cursor       = 0;
+        input->has_cursor   = 0;
         input->cursor_count = 0;
         list_init( &input->msg_list );
         set_caret_window( input, 0 );
@@ -441,7 +443,7 @@ static int update_desktop_cursor_window( struct desktop *desktop, user_handle_t
         if ((thread = get_window_thread( win )))
         {
             struct thread_input *input = thread->queue->input;
-            if (input) handle = input->cursor_count < 0 ? 0 : input->cursor;
+            if (input && input->has_cursor) handle = input->cursor_count < 0 ? 0 : input->cursor;
             release_object( thread );
         }

@@ -3385,6 +3387,7 @@ DECL_HANDLER(set_cursor)
             return;
         }
         input->cursor = req->handle;
+        input->has_cursor = 1;
     }
     if (req->flags & SET_CURSOR_COUNT)
     {

[Rémi Bernon (＠rbernon)]

Would it be better to use a specific cursor handle value for when it isn't initialized yet? The issue can also be reproduced with any window procedure that handles `WM_SETCURSOR` to do nothing. We currently ask the driver to set an invisible cursor handle in this case whereas on Windows it ends up with some random cursor, probably the last one used for the desktop.