user32: Return result through NtCallbackReturn for the enum monitors callback.

dlls/user32/sysparams.c

@@ -18,6 +18,8 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 
+#include "ntstatus.h"
+#define WIN32_NO_STATUS
 #include "user_private.h"
 #include "controls.h"
 #include "wine/asm.h"
@@ -849,14 +851,17 @@ __ASM_GLOBAL_FUNC( enum_mon_callback_wrapper,
     "ret" )
 #endif /* __i386__ */
 
-BOOL WINAPI User32CallEnumDisplayMonitor( struct enum_display_monitor_params *params, ULONG size )
+NTSTATUS WINAPI User32CallEnumDisplayMonitor( void *args, ULONG size )
 {
+    struct enum_display_monitor_params *params = args;
+    BOOL ret;
 #ifdef __i386__
-    return enum_mon_callback_wrapper( params->proc, params->monitor, params->hdc,
-                                      &params->rect, params->lparam );
+    ret = enum_mon_callback_wrapper( params->proc, params->monitor, params->hdc,
+                                     &params->rect, params->lparam );
 #else
-    return params->proc( params->monitor, params->hdc, &params->rect, params->lparam );
+    ret = params->proc( params->monitor, params->hdc, &params->rect, params->lparam );
 #endif
+    return NtCallbackReturn( &ret, sizeof(ret), STATUS_SUCCESS );
 }
 
 /***********************************************************************

dlls/user32/user_private.h

@@ -81,7 +81,7 @@ extern ATOM get_class_info( HINSTANCE instance, const WCHAR *name, WNDCLASSEXW *
 
 /* kernel callbacks */
 
-BOOL WINAPI User32CallEnumDisplayMonitor( struct enum_display_monitor_params *params, ULONG size );
+NTSTATUS WINAPI User32CallEnumDisplayMonitor( void *args, ULONG size );
 BOOL WINAPI User32CallSendAsyncCallback( const struct send_async_params *params, ULONG size );
 BOOL WINAPI User32CallWinEventHook( const struct win_event_hook_params *params, ULONG size );
 BOOL WINAPI User32CallWindowProc( struct win_proc_params *params, ULONG size );

dlls/win32u/sysparams.c

@@ -3435,18 +3435,17 @@ BOOL WINAPI NtUserEnumDisplayMonitors( HDC hdc, RECT *rect, MONITORENUMPROC proc
     params.proc = proc;
     params.hdc = hdc;
     params.lparam = lparam;
-    for (i = 0; i < count; i++)
+    for (i = 0; i < count && ret; i++)
     {
         void *ret_ptr;
         ULONG ret_len;
+        NTSTATUS status;
         params.monitor = enum_info[i].handle;
         params.rect = enum_info[i].rect;
-        if (!KeUserModeCallback( NtUserCallEnumDisplayMonitor, &params, sizeof(params),
-                                 &ret_ptr, &ret_len ))
-        {
-            ret = FALSE;
-            break;
-        }
+        status = KeUserModeCallback( NtUserCallEnumDisplayMonitor, &params, sizeof(params),
+                                     &ret_ptr, &ret_len );
+        if (!status && ret_len == sizeof(ret)) ret = *(BOOL *)ret_ptr;
+        else ret = FALSE;
     }
     if (enum_info != enum_buf) free( enum_info );
     return ret;