Sven Baars : win32u: Account for 16-bit instances in find_class().

[Alexandre Julliard]

Module: wine
Branch: master
Commit: d904f84ed01edc7ec56fbd736c3610057c5173b2
URL:    https://gitlab.winehq.org/wine/wine/-/commit/d904f84ed01edc7ec56fbd736c36100...

Author: Sven Baars <sbaars(a)codeweavers.com>
Date:   Wed Dec 14 17:17:12 2022 +0100

win32u: Account for 16-bit instances in find_class().

This mimics the condition in the server.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=53384

---

 dlls/win32u/class.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/dlls/win32u/class.c b/dlls/win32u/class.c
index b18fd69edfc..9f3b4251e65 100644
--- a/dlls/win32u/class.c
+++ b/dlls/win32u/class.c
@@ -353,8 +353,9 @@ static void release_class_ptr( CLASS *ptr )
 static CLASS *find_class( HINSTANCE module, UNICODE_STRING *name )
 {
     ATOM atom = get_int_atom_value( name );
-    ULONG_PTR instance = (UINT_PTR)module & ~0xffff;
+    ULONG_PTR instance = (UINT_PTR)module;
     CLASS *class;
+    int is_win16;
 
     user_lock();
     LIST_FOR_EACH_ENTRY( class, &class_list, CLASS, entry )
@@ -368,7 +369,9 @@ static CLASS *find_class( HINSTANCE module, UNICODE_STRING *name )
             if (wcsnicmp( class->name, name->Buffer, name->Length / sizeof(WCHAR) ) ||
                 class->name[name->Length / sizeof(WCHAR)]) continue;
         }
-        if (!class->local || !module || (class->instance & ~0xffff) == instance)
+        is_win16 = !(class->instance >> 16);
+        if (!instance || !class->local || class->instance == instance ||
+            (!is_win16 && ((class->instance & ~0xffff) == (instance & ~0xffff))))
         {
             TRACE( "%s %lx -> %p\n", debugstr_us(name), instance, class );
             return class;