master e9bb2d7f4e 2/2: Fix Motif DND return value upon transfer failure

[Po Lu]

branch: master
commit e9bb2d7f4ec47bd3a19df8ceaa43d0ad36dbf9b3
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Fix Motif DND return value upon transfer failure
    
    * src/xterm.c (handle_one_xevent): Make XmTRANSFER_FAILURE clear
    DND action.
---
 src/xterm.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/xterm.c b/src/xterm.c
index 8533961993..484637807a 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -15502,7 +15502,14 @@ handle_one_xevent (struct x_display_info *dpyinfo,
            && eventp->selection == dpyinfo->Xatom_XdndSelection
            && (eventp->target == dpyinfo->Xatom_XmTRANSFER_SUCCESS
                || eventp->target == dpyinfo->Xatom_XmTRANSFER_FAILURE))
-         x_dnd_waiting_for_finish = false;
+         {
+           x_dnd_waiting_for_finish = false;
+
+           /* If the transfer failed, then return nil from
+              `x-begin-drag'.  */
+           if (eventp->target == dpyinfo->Xatom_XmTRANSFER_FAILURE)
+             x_dnd_action = None;
+         }
       }
       break;