user32: Return result through NtCallbackReturn for the DDE message callback.

dlls/user32/user_main.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 "imm.h"
@@ -179,18 +181,17 @@ static BOOL WINAPI User32LoadDriver( const WCHAR *path, ULONG size )
     return LoadLibraryW( path ) != NULL;
 }
 
-static NTSTATUS WINAPI User32UnpackDDEMessage( const struct unpack_dde_message_params *params, ULONG size )
+static NTSTATUS WINAPI User32UnpackDDEMessage( void *args, ULONG size )
 {
+    const struct unpack_dde_message_params *params = args;
     struct unpack_dde_message_result result = { .wparam = params->wparam, .lparam = params->lparam };
 
     size -= FIELD_OFFSET( struct unpack_dde_message_params, data );
     if (!unpack_dde_message( params->hwnd, params->message, &result.wparam, &result.lparam,
                              params->data, size ))
-        return FALSE;
+        return STATUS_NO_MEMORY;
 
-    if (params->result) *params->result = result;
-    else NtCallbackReturn( &result, sizeof(result), TRUE );
-    return TRUE;
+    return NtCallbackReturn( &result, sizeof(result), STATUS_SUCCESS );
 }
 
 static const void *kernel_callback_table[NtUserCallCount] =

dlls/win32u/message.c

@@ -2894,27 +2894,27 @@ static int peek_message( MSG *msg, HWND hwnd, UINT first, UINT last, UINT flags,
             }
             if (info.msg.message >= WM_DDE_FIRST && info.msg.message <= WM_DDE_LAST)
             {
-                struct unpack_dde_message_result result;
+                struct unpack_dde_message_result *result;
                 struct unpack_dde_message_params *params;
-                void *ret_ptr;
+                NTSTATUS status;
                 ULONG len;
-                BOOL ret;
 
                 len = FIELD_OFFSET( struct unpack_dde_message_params, data[size] );
                 if (!(params = malloc( len )))
                     continue;
-                params->result  = &result;
                 params->hwnd    = info.msg.hwnd;
                 params->message = info.msg.message;
                 params->wparam  = info.msg.wParam;
                 params->lparam  = info.msg.lParam;
                 if (size) memcpy( params->data, buffer, size );
-                ret = KeUserModeCallback( NtUserUnpackDDEMessage, params, len, &ret_ptr, &len );
-                if (len == sizeof(result)) result = *(struct unpack_dde_message_result *)ret_ptr;
+                status = KeUserModeCallback( NtUserUnpackDDEMessage, params, len, (void **)&result, &len );
                 free( params );
-                if (!ret) continue; /* ignore it */
-                info.msg.wParam = result.wparam;
-                info.msg.lParam = result.lparam;
+                if (status) continue; /* ignore it */
+                if (len == sizeof(*result))
+                {
+                    info.msg.wParam = result->wparam;
+                    info.msg.lParam = result->lparam;
+                }
             }
             *msg = info.msg;
             msg->pt = point_phys_to_win_dpi( info.msg.hwnd, info.msg.pt );

dlls/wow64win/user.c

@@ -399,7 +399,6 @@ struct draw_text_params32
 
 struct unpack_dde_message_params32
 {
-    ULONG result;
     ULONG hwnd;
     UINT message;
     LONG wparam;
@@ -1395,14 +1394,13 @@ static NTSTATUS WINAPI wow64_NtUserUnpackDDEMessage( void *arg, ULONG size )
         LONG wparam;
         LONG lparam;
     } *result32;
-    void *ret_ptr;
     ULONG ret_len;
+    NTSTATUS status;
 
     size -= FIELD_OFFSET( struct unpack_dde_message_params, data );
     if (!(params32 = Wow64AllocateTemp( FIELD_OFFSET( struct unpack_dde_message_params32, data[size] ))))
-        return 0;
+        return STATUS_NO_MEMORY;
 
-    params32->result = 0;
     params32->hwnd = HandleToUlong( params->hwnd );
     params32->message = params->message;
     params32->wparam = params->wparam;
@@ -1410,18 +1408,14 @@ static NTSTATUS WINAPI wow64_NtUserUnpackDDEMessage( void *arg, ULONG size )
     if (size) memcpy( params32->data, params->data, size );
     size = FIELD_OFFSET( struct unpack_dde_message_params32, data[size] );
 
-    if (!Wow64KiUserCallbackDispatcher( NtUserUnpackDDEMessage, params32, size, &ret_ptr, &ret_len ))
-        return FALSE;
-    if (ret_len == sizeof(*result32))
+    status = Wow64KiUserCallbackDispatcher( NtUserUnpackDDEMessage, params32, size, (void **)&result32, &ret_len );
+    if (!status && ret_len == sizeof(*result32))
     {
-        result32 = ret_ptr;
         result.wparam = result32->wparam;
         result.lparam = result32->lparam;
+        return NtCallbackReturn( &result, sizeof(result), status );
     }
-
-    if (!params->result) NtCallbackReturn( &result, sizeof(result), TRUE );
-    *params->result = result;
-    return TRUE;
+    return status;
 }
 
 static NTSTATUS WINAPI wow64_NtUserCallFreeIcon( void *arg, ULONG size )

include/ntuser.h

@@ -262,21 +262,19 @@ struct render_synthesized_format_params
 };
 
 /* NtUserUnpackDDEMessage params */
-struct unpack_dde_message_result
-{
-    WPARAM wparam;
-    LPARAM lparam;
-};
-
 struct unpack_dde_message_params
 {
-    struct unpack_dde_message_result *result;  /* FIXME: Use NtCallbackReturn instead */
     HWND hwnd;
     UINT message;
     WPARAM wparam;
     LPARAM lparam;
     char data[1];
 };
+struct unpack_dde_message_result
+{
+    WPARAM wparam;
+    LPARAM lparam;
+};
 
 /* process DPI awareness contexts */
 #define NTUSER_DPI_UNAWARE                0x00006010