Make sure a thread has a queue as soon as it creates a window.

server/queue.c

@@ -282,7 +282,7 @@ struct hook_table *get_queue_hooks( struct thread *thread )
 void set_queue_hooks( struct thread *thread, struct hook_table *hooks )
 {
     struct msg_queue *queue = thread->queue;
-    if (!queue) queue = create_msg_queue( thread, NULL );
+    if (!queue && !(queue = create_msg_queue( thread, NULL ))) return;
     if (queue->hooks) release_object( queue->hooks );
     queue->hooks = hooks;
 }
@@ -828,6 +828,13 @@ static int check_queue_input_window( struct msg_queue *queue, user_handle_t wind
     return ret;
 }
 
+/* make sure the specified thread has a queue */
+int init_thread_queue( struct thread *thread )
+{
+    if (thread->queue) return 1;
+    return (create_msg_queue( thread, NULL ) != NULL);
+}
+
 /* attach two thread input data structures */
 int attach_thread_input( struct thread *thread_from, struct thread *thread_to )
 {

server/user.h

@@ -61,6 +61,7 @@ extern struct hook_table *get_queue_hooks( struct thread *thread );
 extern void set_queue_hooks( struct thread *thread, struct hook_table *hooks );
 extern void inc_queue_paint_count( struct thread *thread, int incr );
 extern void queue_cleanup_window( struct thread *thread, user_handle_t win );
+extern int init_thread_queue( struct thread *thread );
 extern int attach_thread_input( struct thread *thread_from, struct thread *thread_to );
 extern void post_message( user_handle_t win, unsigned int message,
                           unsigned int wparam, unsigned int lparam );

server/window.c

@@ -338,13 +338,8 @@ static struct window *create_window( struct window *parent, struct window *owner
         release_class( class );
         return NULL;
     }
+    if (!(win->handle = alloc_user_handle( win, USER_WINDOW ))) goto failed;
 
-    if (!(win->handle = alloc_user_handle( win, USER_WINDOW )))
-    {
-        release_class( class );
-        free( win );
-        return NULL;
-    }
     win->parent         = parent;
     win->owner          = owner ? owner->handle : 0;
     win->thread         = current;
@@ -368,13 +363,26 @@ static struct window *create_window( struct window *parent, struct window *owner
     list_init( &win->children );
     list_init( &win->unlinked );
 
+    /* if parent belongs to a different thread, attach the two threads */
+    if (parent && parent->thread && parent->thread != current)
+    {
+        if (!attach_thread_input( current, parent->thread )) goto failed;
+    }
+    else  /* otherwise just make sure that the thread has a message queue */
+    {
+        if (!current->queue && !init_thread_queue( current )) goto failed;
+    }
+
     /* put it on parent unlinked list */
     if (parent) list_add_head( &parent->unlinked, &win->entry );
 
-    /* if parent belongs to a different thread, attach the two threads */
-    if (parent && parent->thread && parent->thread != current)
-        attach_thread_input( current, parent->thread );
     return win;
+
+failed:
+    if (win->handle) free_user_handle( win->handle );
+    release_class( class );
+    free( win );
+    return NULL;
 }
 
 /* destroy all windows belonging to a given thread */