master 52c31f9e13: Support Motif DND help

[Po Lu]

branch: master
commit 52c31f9e13c349609091620ecf56ac42747c1652
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Support Motif DND help
    
    * src/xterm.c (x_dnd_xm_use_help): New state variable.
    (x_dnd_begin_drag_and_drop): Clear new variable.
    (handle_one_xevent): Set new variable if we get a key press
    event F1 during the drag-and-drop session, and use help action
    when dropping onto a Motif program if it is set.
---
 src/xterm.c | 31 +++++++++++++++++++++++++++----
 1 file changed, 27 insertions(+), 4 deletions(-)

diff --git a/src/xterm.c b/src/xterm.c
index 07074d19cb..b2059e69aa 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -851,6 +851,7 @@ static bool x_dnd_waiting_for_finish;
    target to convert one of the special selections XmTRANSFER_SUCCESS
    or XmTRANSFER_FAILURE.  */
 static int x_dnd_waiting_for_motif_finish;
+static bool x_dnd_xm_use_help;
 static Window x_dnd_pending_finish_target;
 static int x_dnd_waiting_for_finish_proto;
 static bool x_dnd_allow_current_frame;
@@ -1011,7 +1012,7 @@ typedef struct xm_drag_receiver_info
 #define XM_DRAG_LINK (1L << 2)
 
 #define XM_DROP_ACTION_DROP            0
-/* #define XM_DROP_ACTION_DROP_HELP    1 */
+#define XM_DROP_ACTION_DROP_HELP       1
 #define XM_DROP_ACTION_DROP_CANCEL     2
 
 #define XM_DRAG_REASON(originator, code)       ((code) | ((originator) << 7))
@@ -8648,6 +8649,7 @@ x_dnd_begin_drag_and_drop (struct frame *f, Time time, 
Atom xaction,
   x_dnd_return_frame = 0;
   x_dnd_waiting_for_finish = false;
   x_dnd_waiting_for_motif_finish = 0;
+  x_dnd_xm_use_help = false;
   x_dnd_end_window = None;
   x_dnd_use_toplevels
     = x_wm_supports (f, FRAME_DISPLAY_INFO 
(f)->Xatom_net_client_list_stacking);
@@ -12597,7 +12599,8 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                  }
 
                if (status != XM_DROP_SITE_VALID
-                   || action == XM_DROP_ACTION_DROP_CANCEL)
+                   || (action == XM_DROP_ACTION_DROP_CANCEL
+                       || action == XM_DROP_ACTION_DROP_HELP))
                  {
                    x_dnd_waiting_for_finish = false;
                    goto OTHER;
@@ -13542,6 +13545,14 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                                   &compose_status);
 #endif
 
+#ifdef XK_F1
+         if (x_dnd_in_progress && keysym == XK_F1)
+           {
+             x_dnd_xm_use_help = true;
+             goto done_keysym;
+           }
+#endif
+
           /* If not using XIM/XIC, and a compose sequence is in progress,
              we break here.  Otherwise, chars_matched is always 0.  */
           if (compose_status.chars_matched > 0 && nbytes == 0)
@@ -14441,7 +14452,9 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                              = XM_DRAG_SIDE_EFFECT (xm_side_effect_from_action 
(dpyinfo,
                                                                                
 x_dnd_wanted_action),
                                                     XM_DROP_SITE_VALID, 
XM_DRAG_NOOP,
-                                                    XM_DROP_ACTION_DROP);
+                                                    (x_dnd_xm_use_help
+                                                     ? XM_DROP_ACTION_DROP
+                                                     : 
XM_DROP_ACTION_DROP_HELP));
                            dmsg.timestamp = event->xbutton.time;
                            dmsg.x = event->xbutton.x_root;
                            dmsg.y = event->xbutton.y_root;
@@ -15495,7 +15508,9 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                                                           XM_DROP_SITE_VALID,
                                                           
xm_side_effect_from_action (dpyinfo,
                                                                                
       x_dnd_wanted_action),
-                                                          XM_DROP_ACTION_DROP);
+                                                          (x_dnd_xm_use_help
+                                                           ? 
XM_DROP_ACTION_DROP
+                                                           : 
XM_DROP_ACTION_DROP_HELP));
                                  dmsg.timestamp = xev->time;
                                  dmsg.x = lrint (xev->root_x);
                                  dmsg.y = lrint (xev->root_y);
@@ -16115,6 +16130,14 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                        }
                    }
 
+#ifdef XK_F1
+                 if (x_dnd_in_progress && keysym == XK_F1)
+                   {
+                     x_dnd_xm_use_help = true;
+                     goto xi_done_keysym;
+                   }
+#endif
+
                  /* First deal with keysyms which have defined
                     translations to characters.  */
                  if (keysym >= 32 && keysym < 128)