Ibuffer: Mark locked buffers

* lisp/ibuf-ext.el (ibuffer-locked-buffer-p): New defun.
(ibuffer-mark-by-locked): New command.
(ibuffer-mode-map): Bind it to '% L'; update menus.
(ibuffer-mode): Update mode doc.
;* etc/NEWS: Add NEWS entry for these changes and previous two commits.

etc/NEWS

@@ -198,6 +198,15 @@ same as in modes where the character is not whitespace.
 
 ** Ibuffer
 
+---
+*** A new command 'ibuffer-mark-by-locked' to mark
+all locked buffers;  bound to '% L'.
+
+---
+*** A new option 'ibuffer-locked-char' to indicate
+locked buffers; Ibuffer shows a new column displaying
+'ibuffer-locked-char' for locked buffers.
+
 ---
 *** A new command 'ibuffer-unmark-all-marks' to unmark
 all buffers without asking confirmation;  bound to

lisp/ibuf-ext.el

@@ -1484,6 +1484,24 @@ You can then feed the file name(s) to other commands with \\[yank]."
    #'(lambda (buf)
        (string-match regexp (buffer-name buf)))))
 
+(defun ibuffer-locked-buffer-p (&optional buf)
+  "Return non-nil if BUF is locked.
+When BUF nil, default to the buffer at current line."
+  (let ((_buffer (or buf (ibuffer-current-buffer)))
+        char)
+    (when _buffer
+      (with-current-buffer _buffer
+        (and (boundp 'emacs-lock-mode) emacs-lock-mode)))))
+
+;;;###autoload
+(defun ibuffer-mark-by-locked ()
+  "Mark all locked buffers."
+  (interactive)
+  (when (featurep 'emacs-lock)
+    (ibuffer-mark-on-buffer
+     (lambda (buf)
+       (ibuffer-locked-buffer-p buf)))))
+
 ;;;###autoload
 (defun ibuffer-mark-by-mode-regexp (regexp)
   "Mark all buffers whose major mode matches REGEXP."

lisp/ibuffer.el

@@ -556,6 +556,7 @@ directory, like `default-directory'."
     (define-key map (kbd "% m") 'ibuffer-mark-by-mode-regexp)
     (define-key map (kbd "% f") 'ibuffer-mark-by-file-name-regexp)
     (define-key map (kbd "% g") 'ibuffer-mark-by-content-regexp)
+    (define-key map (kbd "% L") 'ibuffer-mark-by-locked)
 
     (define-key map (kbd "C-t") 'ibuffer-visit-tags-table)
 
@@ -782,6 +783,9 @@ directory, like `default-directory'."
       '(menu-item "Mark by content (regexp)..."
         ibuffer-mark-by-content-regexp
         :help "Mark buffers whose content matches a regexp"))
+    (define-key-after map [menu-bar mark mark-by-locked]
+      '(menu-item "Mark by locked buffers..." ibuffer-mark-by-locked
+        :help "Mark all locked buffers"))
 
     map))
 
@@ -2476,6 +2480,7 @@ Marking commands:
   `\\[ibuffer-mark-by-mode-regexp]' - Mark buffers by their major mode, using a regexp.
   `\\[ibuffer-mark-by-file-name-regexp]' - Mark buffers by their filename, using a regexp.
   `\\[ibuffer-mark-by-content-regexp]' - Mark buffers by their content, using a regexp.
+  `\\[ibuffer-mark-by-locked]' - Mark all locked buffers.
 
 Filtering commands: