[PATCH v5 4/6] win32u: Allow drivers to set the null user driver.

[Alexandros Frantzis]

From: Alexandros Frantzis

Allow passing NULL as the user driver to __wine_set_user_driver(),
to set the internal null user driver. This is useful for drivers
that may need to tentatively set their own user driver during setup
and reset it on failure.

Signed-off-by: Alexandros Frantzis 
---
 dlls/win32u/driver.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/win32u/driver.c b/dlls/win32u/driver.c
index eb736de272d..5bae77da5f4 100644
--- a/dlls/win32u/driver.c
+++ b/dlls/win32u/driver.c
@@ -1241,7 +1241,7 @@ void __wine_set_user_driver( const struct user_driver_funcs *funcs, UINT version
     }

driver = malloc( sizeof(*driver) );
-    *driver = *funcs;
+    *driver = funcs ? *funcs : null_user_driver;

#define SET_USER_FUNC(name) \
     do { if (!driver->p##name) driver->p##name = nulldrv_##name; } while(0)