Allow disabling Motif drag protocol

* lisp/cus-start.el (standard): Add new variable.
* src/xterm.c (x_dnd_update_state, handle_one_xevent): Respect
new variable.
(syms_of_xterm): New variable `x-dnd-disable-motif-drag'.

diff --git a/lisp/cus-start.el b/lisp/cus-start.el
index 83ab61b28b5e1b63c8cdc727fe88d47b07676197..d8c4b480359421ff800d5ade5dcfc8d6a1b5ac12 100644 (file)
--- a/lisp/cus-start.el
+++ b/lisp/cus-start.el
@@ -832,6 +832,7 @@ since it could result in memory overflow and make Emacs crash."
             (scroll-bar-adjust-thumb-portion windows boolean "24.4")
              (x-scroll-event-delta-factor mouse float "29.1")
              (x-gtk-use-native-input keyboard boolean "29.1")
+             (x-dnd-disable-motif-drag dnd boolean "29.1")
             ;; xselect.c
             (x-select-enable-clipboard-manager killing boolean "24.1")
             ;; xsettings.c
@@ -870,6 +871,8 @@ since it could result in memory overflow and make Emacs crash."
                       ((or (equal "scroll-bar-adjust-thumb-portion"
                                  (symbol-name symbol))
                            (equal "x-scroll-event-delta-factor"
+                                  (symbol-name symbol))
+                           (equal "x-dnd-disable-motif-drag"
                                   (symbol-name symbol)))
                       (featurep 'x))
                      ((string-match "\\`x-" (symbol-name symbol))

diff --git a/src/xterm.c b/src/xterm.c
index 2bbc9f3d0c6643e81b9e8a9917b3f9aacd154b2e..c9e2618191266f50936cdc806b68cbe4bdaa182e 100644 (file)
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -14053,6 +14053,7 @@ x_dnd_update_state (struct x_display_info *dpyinfo, Time timestamp)
                x_dnd_send_leave (x_dnd_frame, x_dnd_last_seen_window);
              else if (x_dnd_last_seen_window != None
                       && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                      && !x_dnd_disable_motif_drag
                       && x_dnd_last_seen_window != FRAME_OUTER_WINDOW (x_dnd_frame))
                {
                  if (!x_dnd_motif_setup_p)
@@ -14092,6 +14093,7 @@ x_dnd_update_state (struct x_display_info *dpyinfo, Time timestamp)
            x_dnd_send_leave (x_dnd_frame, x_dnd_last_seen_window);
          else if (x_dnd_last_seen_window != None
                   && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                  && !x_dnd_disable_motif_drag
                   && x_dnd_last_seen_window != FRAME_OUTER_WINDOW (x_dnd_frame))
            {
              if (!x_dnd_motif_setup_p)
@@ -14117,7 +14119,8 @@ x_dnd_update_state (struct x_display_info *dpyinfo, Time timestamp)
          if (target != None && x_dnd_last_protocol_version != -1)
            x_dnd_send_enter (x_dnd_frame, target,
                              x_dnd_last_protocol_version);
-         else if (target != None && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style))
+         else if (target != None && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                  && !x_dnd_disable_motif_drag)
            {
              if (!x_dnd_motif_setup_p)
                xm_setup_drag_info (dpyinfo, x_dnd_frame);
@@ -14148,7 +14151,8 @@ x_dnd_update_state (struct x_display_info *dpyinfo, Time timestamp)
                             0
 #endif
                             );
-      else if (XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style) && target != None)
+      else if (XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style) && target != None
+              && !x_dnd_disable_motif_drag)
        {
          if (!x_dnd_motif_setup_p)
            xm_setup_drag_info (dpyinfo, x_dnd_frame);
@@ -15875,6 +15879,7 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                      x_dnd_send_leave (x_dnd_frame, x_dnd_last_seen_window);
                    else if (x_dnd_last_seen_window != None
                             && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                            && !x_dnd_disable_motif_drag
                             && x_dnd_last_seen_window != FRAME_OUTER_WINDOW (x_dnd_frame))
                      {
                        if (!x_dnd_motif_setup_p)
@@ -15914,6 +15919,7 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                  x_dnd_send_leave (x_dnd_frame, x_dnd_last_seen_window);
                else if (x_dnd_last_seen_window != None
                         && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                        && x_dnd_disable_motif_drag
                         && x_dnd_last_seen_window != FRAME_OUTER_WINDOW (x_dnd_frame))
                  {
                    if (!x_dnd_motif_setup_p)
@@ -15960,7 +15966,8 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                if (target != None && x_dnd_last_protocol_version != -1)
                  x_dnd_send_enter (x_dnd_frame, target,
                                    x_dnd_last_protocol_version);
-               else if (target != None && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style))
+               else if (target != None && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                        && !x_dnd_disable_motif_drag)
                  {
                    if (!x_dnd_motif_setup_p)
                      xm_setup_drag_info (dpyinfo, x_dnd_frame);
@@ -15987,7 +15994,8 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                                   x_dnd_selection_timestamp,
                                   x_dnd_wanted_action, 0,
                                   event->xmotion.state);
-           else if (XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style) && target != None)
+           else if (XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style) && target != None
+                    && !x_dnd_disable_motif_drag)
              {
                if (!x_dnd_motif_setup_p)
                  xm_setup_drag_info (dpyinfo, x_dnd_frame);
@@ -17454,6 +17462,7 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                            x_dnd_send_leave (x_dnd_frame, x_dnd_last_seen_window);
                          else if (x_dnd_last_seen_window != None
                                   && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                                  && !x_dnd_disable_motif_drag
                                   && x_dnd_last_seen_window != FRAME_OUTER_WINDOW (x_dnd_frame))
                            {
                              if (!x_dnd_motif_setup_p)
@@ -17493,6 +17502,7 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                        x_dnd_send_leave (x_dnd_frame, x_dnd_last_seen_window);
                      else if (x_dnd_last_seen_window != None
                               && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                              && !x_dnd_disable_motif_drag
                               && x_dnd_last_seen_window != FRAME_OUTER_WINDOW (x_dnd_frame))
                        {
                          if (!x_dnd_motif_setup_p)
@@ -17541,7 +17551,8 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                      if (target != None && x_dnd_last_protocol_version != -1)
                        x_dnd_send_enter (x_dnd_frame, target,
                                          x_dnd_last_protocol_version);
-                     else if (target != None && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style))
+                     else if (target != None && XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style)
+                              && !x_dnd_disable_motif_drag)
                        {
                          if (!x_dnd_motif_setup_p)
                            xm_setup_drag_info (dpyinfo, x_dnd_frame);
@@ -17581,7 +17592,8 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                                           x_dnd_wanted_action, 0,
                                           dnd_state);
                    }
-                 else if (XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style) && target != None)
+                 else if (XM_DRAG_STYLE_IS_DYNAMIC (x_dnd_last_motif_style) && target != None
+                          && !x_dnd_disable_motif_drag)
                    {
                      if (!x_dnd_motif_setup_p)
                        xm_setup_drag_info (dpyinfo, x_dnd_frame);
@@ -24906,6 +24918,13 @@ during a drag-and-drop session, to work around broken implementations
 of Motif.  */);
   x_dnd_fix_motif_leave = true;
 
+  DEFVAR_BOOL ("x-dnd-disable-motif-drag", x_dnd_disable_motif_drag,
+              doc: /* Disable the Motif drag protocol during DND.
+This reduces network usage, but also means you can no longer scroll
+around inside the Motif window underneath the cursor during
+drag-and-drop.  */);
+  x_dnd_disable_motif_drag = false;
+
   DEFVAR_LISP ("x-dnd-movement-function", Vx_dnd_movement_function,
     doc: /* Function called upon mouse movement on a frame during drag-and-drop.
 It should either be nil, or accept two arguments FRAME and POSITION,