Revert 2010-07-14 change to deactivate mark; minor cleanups.

* mouse.el (mouse-drag-track): Use select-active-region.

* simple.el (select-active-region): New function.
(push-mark-command, set-mark, activate-mark)
(handle-shift-selection): Use it.
(deactivate-mark): Don't check for size of region.

lisp/ChangeLog

@@ -1,3 +1,12 @@
+2010-07-17  Chong Yidong  <cyd@stupidchicken.com>
+
+	* simple.el (select-active-region): New function.
+	(push-mark-command, set-mark, activate-mark)
+	(handle-shift-selection): Use it.
+	(deactivate-mark): Don't check for size of region.
+
+	* mouse.el (mouse-drag-track): Use select-active-region.
+
 2010-07-17  Michael Albinus  <michael.albinus@gmx.de>
 
 	* net/tramp.el (tramp-get-ls-command-with-dired): Make test for

lisp/mouse.el

@@ -1027,9 +1027,7 @@ DO-MOUSE-DRAG-REGION-POST-PROCESS should only be used by
 	      ;; For `select-active-regions' non-nil, ensure that
 	      ;; further alterations of the region (e.g. via
 	      ;; shift-selection) continue to update PRIMARY.
-	      (and select-active-regions
-		   (display-selections-p)
-		   (x-set-selection 'PRIMARY (current-buffer))))
+	      (select-active-region))
 
 	  ;; If point hasn't moved, run the binding of the
 	  ;; terminating up-event.

lisp/simple.el

@@ -3687,7 +3687,6 @@ This function also runs `deactivate-mark-hook'."
 	 mark-active
 	 (display-selections-p)
 	 (x-selection-owner-p 'PRIMARY)
-	 (not (eq (region-beginning) (region-end)))
 	 (x-set-selection 'PRIMARY (buffer-substring-no-properties
 				    (region-beginning) (region-end))))
     (if (and (null force)
@@ -3708,9 +3707,13 @@ This function also runs `deactivate-mark-hook'."
     (setq mark-active t)
     (unless transient-mark-mode
       (setq transient-mark-mode 'lambda))
-    (when (and select-active-regions
-	       (display-selections-p))
-      (x-set-selection 'PRIMARY (current-buffer)))))
+    (select-active-region)))
+
+(defsubst select-active-region ()
+  "Set the PRIMARY X selection if `select-active-regions' is non-nil."
+  (and select-active-regions
+       (display-selections-p)
+       (x-set-selection 'PRIMARY (current-buffer))))
 
 (defun set-mark (pos)
   "Set this buffer's mark to POS.  Don't use this function!
@@ -3733,9 +3736,7 @@ store it in a Lisp variable.  Example:
       (progn
 	(setq mark-active t)
 	(run-hooks 'activate-mark-hook)
-	(when (and select-active-regions
-		   (display-selections-p))
-	  (x-set-selection 'PRIMARY (current-buffer)))
+	(select-active-region)
 	(set-marker (mark-marker) pos (current-buffer)))
     ;; Normally we never clear mark-active except in Transient Mark mode.
     ;; But when we actually clear out the mark value too, we must
@@ -3819,8 +3820,7 @@ Display `Mark set' unless the optional second arg NOMSG is non-nil."
 	(push-mark nil nomsg t)
       (setq mark-active t)
       (run-hooks 'activate-mark-hook)
-      (and select-active-regions (display-selections-p)
-	   (x-set-selection 'PRIMARY (current-buffer)))
+      (select-active-region)
       (unless nomsg
 	(message "Mark activated")))))
 
@@ -4008,9 +4008,12 @@ Otherwise, if the region has been activated temporarily,
 deactivate it, and restore the variable `transient-mark-mode' to
 its earlier value."
   (cond ((and shift-select-mode this-command-keys-shift-translated)
-         (unless (and mark-active
-                      (eq (car-safe transient-mark-mode) 'only))
-           (setq transient-mark-mode
+         (if (and mark-active
+		  (eq (car-safe transient-mark-mode) 'only))
+	     ;; Another program may have grabbed the selection; make
+	     ;; sure we get it back now.
+	     (select-active-region)
+	   (setq transient-mark-mode
                  (cons 'only
                        (unless (eq transient-mark-mode 'lambda)
                          transient-mark-mode)))