master ec6f6d23eb: Fix XDND from Firefox again

[Po Lu]

branch: master
commit ec6f6d23eb37ebd4fad17eb02730bf463aa27c5a
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Fix XDND from Firefox again
    
    * lisp/x-dnd.el (x-dnd-handle-xdnd): Prevent nil from appearing
    in format 32 list.
    (x-dnd-handle-motif): Send reply if the user quit out of the
    drop handler as well.
---
 lisp/x-dnd.el | 75 +++++++++++++++++++++++++++++++----------------------------
 1 file changed, 39 insertions(+), 36 deletions(-)

diff --git a/lisp/x-dnd.el b/lisp/x-dnd.el
index d4aa68a10d..22277033f5 100644
--- a/lisp/x-dnd.el
+++ b/lisp/x-dnd.el
@@ -636,24 +636,26 @@ FORMAT is 32 (not used).  MESSAGE is the data part of an 
XClientMessageEvent."
                             timestamp)))
                success action)
            (x-display-set-last-user-time timestamp)
-          (setq action (if value
-                           (condition-case info
-                               (x-dnd-drop-data event frame window value
-                                                (x-dnd-current-type window))
-                             (error
-                              (message "Error: %s" info)
-                              nil))))
-          (setq success (if action 1 0))
-           (when (>= version 2)
-            (x-send-client-message
-             frame dnd-source frame "XdndFinished" 32
-             (list (string-to-number
-                     (frame-parameter frame 'outer-window-id))
-                   (if (>= version 5) success 0) ;; 1 = Success, 0 = Error
-                    (when (>= version 5)
-                     (if (not success) 0
-                        (car (rassoc action
-                                     x-dnd-xdnd-to-action)))))))
+           (unwind-protect
+               (setq action (if value
+                               (condition-case info
+                                   (x-dnd-drop-data
+                                     event frame window value
+                                    (x-dnd-current-type window))
+                                 (error
+                                  (message "Error: %s" info)
+                                  nil))))
+            (setq success (if action 1 0))
+             (when (>= version 2)
+              (x-send-client-message
+               frame dnd-source frame "XdndFinished" 32
+               (list (string-to-number
+                       (frame-parameter frame 'outer-window-id))
+                     (if (>= version 5) success 0) ;; 1 = Success, 0 = Error
+                     (if (or (not success) (< version 5)) 0
+                        (or (car (rassoc action
+                                         x-dnd-xdnd-to-action))
+                            0))))))
           (x-dnd-forget-drop window)))
 
        (t (error "Unknown XDND message %s %s" message data))))
@@ -981,24 +983,25 @@ Return a vector of atoms containing the selection 
targets."
                                        "_MOTIF_DRAG_AND_DROP_MESSAGE"
                                        8
                                        reply)
-                (setq action
-                      (when (and reply-action atom-name)
-                        (let* ((value (x-get-selection-internal
-                                       (intern atom-name)
-                                       (intern (x-dnd-current-type window))
-                                        timestamp)))
-                          (when value
-                            (condition-case info
-                                (x-dnd-drop-data event frame window value
-                                                 (x-dnd-current-type window))
-                              (error
-                               (message "Error: %s" info)
-                               nil))))))
-                (x-get-selection-internal
-                 (intern atom-name)
-                 (if action 'XmTRANSFER_SUCCESS 'XmTRANSFER_FAILURE)
-                 timestamp)
-                (x-dnd-forget-drop frame))))
+                (unwind-protect
+                     (setq action
+                          (when (and reply-action atom-name)
+                            (let* ((value (x-get-selection-internal
+                                           (intern atom-name)
+                                           (intern (x-dnd-current-type window))
+                                            timestamp)))
+                              (when value
+                                (condition-case info
+                                    (x-dnd-drop-data event frame window value
+                                                     (x-dnd-current-type 
window))
+                                  (error
+                                   (message "Error: %s" info)
+                                   nil))))))
+                  (x-get-selection-internal
+                   (intern atom-name)
+                   (if action 'XmTRANSFER_SUCCESS 'XmTRANSFER_FAILURE)
+                   timestamp)
+                  (x-dnd-forget-drop frame)))))
 
             (t (message "Unknown Motif drag-and-drop message: %s"
                         (logand (aref data 0) #x3f)))))))