Don't allow dropping on invalid drop sites

* lisp/x-dnd.el (x-dnd-drop-data): If dropping on something
other than the text area, don't set point.
(x-dnd-handle-xdnd, x-dnd-handle-motif): Don't pretend dropping
on the mode line is ok.

diff --git a/lisp/x-dnd.el b/lisp/x-dnd.el
index f3abb9d5e6d7fc7a01ffd349c63a965cd02ae676..7befea7418f0020de9b39fe3a81add515712d9e3 100644 (file)
--- a/lisp/x-dnd.el
+++ b/lisp/x-dnd.el
@@ -333,7 +333,10 @@ nil if not."
          ;; If dropping in an ordinary window which we could use,
          ;; let dnd-open-file-other-window specify what to do.
          (progn
-           (when (not mouse-yank-at-point)
+           (when (and (not mouse-yank-at-point)
+                       ;; If dropping on top of the mode line, insert
+                       ;; the text at point instead.
+                       (posn-point (event-start event)))
              (goto-char (posn-point (event-start event))))
            (funcall handler window action data))
        ;; If we can't display the file here,
@@ -487,7 +490,11 @@ FORMAT is 32 (not used).  MESSAGE is the data part of an XClientMessageEvent."
                (reply-action (car (rassoc (car action-type)
                                           x-dnd-xdnd-to-action)))
                (accept ;; 1 = accept, 0 = reject
-                (if (and reply-action action-type) 1 0))
+                (if (and reply-action action-type
+                          ;; Only allow drops on the text area of a
+                          ;; window.
+                          (not (posn-area (event-start event))))
+                     1 0))
                (list-to-send
                 (list (string-to-number
                        (frame-parameter frame 'outer-window-id))
@@ -495,8 +502,7 @@ FORMAT is 32 (not used).  MESSAGE is the data part of an XClientMessageEvent."
                       (x-dnd-get-drop-x-y frame window)
                       (x-dnd-get-drop-width-height
                        frame window (eq accept 1))
-                      (or reply-action 0)
-                      )))
+                      (or reply-action 0))))
           (x-send-client-message
            frame dnd-source frame "XdndStatus" 32 list-to-send)
            (dnd-handle-movement (event-start event))))
@@ -653,13 +659,16 @@ FORMAT is 32 (not used).  MESSAGE is the data part of an XClientMessageEvent."
                    (reply-action (car (rassoc (car action-type)
                                               x-dnd-motif-to-action)))
                    (reply-flags
-                    (x-dnd-motif-value-to-list
-                     (if reply-action
-                         (+ reply-action
-                            ?\x30      ; 30:  valid drop site
-                            ?\x700)    ; 700: can do copy, move or link
-                       ?\x30)          ; 30:  drop site, but noop.
-                     2 my-byteorder))
+                     (if (posn-area (event-start event))
+                         (x-dnd-motif-value-to-list ?\x20 ; 20: invalid drop site
+                                                    2 my-byteorder)
+                      (x-dnd-motif-value-to-list
+                       (if reply-action
+                           (+ reply-action
+                              ?\x30                      ; 30:  valid drop site
+                              ?\x700)                    ; 700: can do copy, move or link
+                         ?\x30)                          ; 30:  drop site, but noop.
+                       2 my-byteorder)))
                    (reply (append
                            (list
                             (+ ?\x80   ; 0x80 indicates a reply.
@@ -691,13 +700,16 @@ FORMAT is 32 (not used).  MESSAGE is the data part of an XClientMessageEvent."
                    (reply-action (car (rassoc (car action-type)
                                               x-dnd-motif-to-action)))
                    (reply-flags
-                    (x-dnd-motif-value-to-list
-                     (if reply-action
-                         (+ reply-action
-                            ?\x30      ; 30:  valid drop site
-                            ?\x700)    ; 700: can do copy, move or link
-                       ?\x30)          ; 30:  drop site, but noop
-                     2 my-byteorder))
+                    (if (posn-area (event-start event))
+                         (x-dnd-motif-value-to-list ?\x20 ; 20: invalid drop site
+                                                    2 my-byteorder)
+                      (x-dnd-motif-value-to-list
+                       (if reply-action
+                           (+ reply-action
+                              ?\x30   ; 30:  valid drop site
+                              ?\x700) ; 700: can do copy, move or link
+                         ?\x30)       ; 30:  drop site, but noop.
+                       2 my-byteorder)))
                    (reply (append
                            (list
                             (+ ?\x80   ; 0x80 indicates a reply.
@@ -727,25 +739,28 @@ FORMAT is 32 (not used).  MESSAGE is the data part of an XClientMessageEvent."
                    (action-type (x-dnd-maybe-call-test-function
                                  window
                                  source-action))
-                   (reply-action (car (rassoc (car action-type)
-                                              x-dnd-motif-to-action)))
+                   (reply-action (and (not (posn-area (event-start event)))
+                                       (car (rassoc (car action-type)
+                                                   x-dnd-motif-to-action))))
                    (reply-flags
                     (x-dnd-motif-value-to-list
-                     (if reply-action
-                         (+ reply-action
-                            ?\x30      ; 30:  valid drop site
-                            ?\x700)    ; 700: can do copy, move or link
-                       (+ ?\x30                ; 30:  drop site, but noop.
-                          ?\x200))     ; 200: drop cancel.
-                     2 my-byteorder))
+                      (if (posn-area (event-start event))
+                          (+ ?\x20     ; 20: invalid drop site
+                             ?\x200)   ; 200: drop cancel
+                       (if reply-action
+                           (+ reply-action
+                              ?\x30   ; 30:  valid drop site
+                              ?\x700) ; 700: can do copy, move or link
+                         (+ ?\x30     ; 30:  drop site, but noop.
+                            ?\x200))) ; 200: drop cancel.
+                       2 my-byteorder))
                    (reply (append
                            (list
                             (+ ?\x80   ; 0x80 indicates a reply.
                                5)      ; DROP_START.
                             my-byteorder)
                            reply-flags
-                           x
-                           y))
+                           x y))
                    (timestamp (x-dnd-get-motif-value
                                data 4 4 source-byteorder))
                    action)
@@ -774,7 +789,8 @@ FORMAT is 32 (not used).  MESSAGE is the data part of an XClientMessageEvent."
                timestamp)
               (x-dnd-forget-drop frame)))
 
-            (t (message "Unknown Motif drag-and-drop message: %s" (logand (aref data 0) #x3f)))))))
+            (t (message "Unknown Motif drag-and-drop message: %s"
+                        (logand (aref data 0) #x3f)))))))
 
 
 ;;;