* subr.el (user-emacs-directory-warning): New option.

(locate-user-emacs-file): Handle non-accessible .emacs.d. 

Not in NEWS, because you only need to know about this if you encounter
it in the wild.

Fixes: debbugs:13930

2 files changed, 37 insertions, 9 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 70431b3f318..ef43f00de1c 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2013-05-14  Glenn Morris  <rgm@gnu.org>
+
+        * subr.el (user-emacs-directory-warning): New option.
+        (locate-user-emacs-file): Handle non-accessible .emacs.d.  (Bug#13930)
+
 2013-05-14  Leo Liu  <sdl.web@gmail.com>
 
         * progmodes/octave.el (octave-font-lock-keywords): Fix error
diff --git a/lisp/subr.el b/lisp/subr.el
index bb23745df72..4871f3733f9 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2643,6 +2643,13 @@ Various programs in Emacs store information in this directory.
 Note that this should end with a directory separator.
 See also `locate-user-emacs-file'.")
 
+(custom-declare-variable-early 'user-emacs-directory-warning t
+  "Non-nil means warn if cannot access `user-emacs-directory'.
+Set this to nil at your own risk..."
+  :type 'boolean
+  :group 'initialization
+  :version "24.4")
+
 (defun locate-user-emacs-file (new-name &optional old-name)
   "Return an absolute per-user Emacs-specific file name.
 If NEW-NAME exists in `user-emacs-directory', return it.
@@ -2658,17 +2665,33 @@ directory if it does not exist."
               (file-readable-p at-home))
          at-home
        ;; Make sure `user-emacs-directory' exists,
-       ;; unless we're in batch mode or dumping Emacs
+       ;; unless we're in batch mode or dumping Emacs.
        (or noninteractive
            purify-flag
-           (file-accessible-directory-p
-            (directory-file-name user-emacs-directory))
-           (let ((umask (default-file-modes)))
-             (unwind-protect
-                 (progn
-                   (set-default-file-modes ?\700)
-                   (make-directory user-emacs-directory))
-               (set-default-file-modes umask))))
+           (let (errtype)
+             (if (file-directory-p user-emacs-directory)
+                 (or (file-accessible-directory-p user-emacs-directory)
+                     (setq errtype "access"))
+               (let ((umask (default-file-modes)))
+                 (unwind-protect
+                     (progn
+                       (set-default-file-modes ?\700)
+                       (condition-case nil
+                           (make-directory user-emacs-directory)
+                         (error (setq errtype "create"))))
+                   (set-default-file-modes umask))))
+             (when (and errtype
+                        user-emacs-directory-warning
+                        (not (get 'user-emacs-directory-warning 'this-session)))
+               ;; Only warn once per Emacs session.
+               (put 'user-emacs-directory-warning 'this-session t)
+               (display-warning 'initialization
+                                (format "\
+Unable to %s `user-emacs-directory' (%s).
+Any data that would normally be written there may be lost!
+If you never want to see this message again,
+customize the variable `user-emacs-directory-warning'."
+                                        errtype user-emacs-directory)))))
        bestname))))
 
 ;;;; Misc. useful functions.