Avoid crash with invalid default-process-coding-system.

[bpt/emacs.git] / lisp / ibuf-ext.el

;;; ibuf-ext.el --- extensions for ibuffer

;; Copyright (C) 2000-2011  Free Software Foundation, Inc.

;; Author: Colin Walters <walters@verbum.org>
;; Maintainer: John Paul Wallington <jpw@gnu.org>
;; Created: 2 Dec 2001
;; Keywords: buffer, convenience
;; Package: ibuffer

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; These functions should be automatically loaded when called, but you
;; can explicity (require 'ibuf-ext) in your ~/.emacs to have them
;; preloaded.

;;; Code:

(require 'ibuffer)

(eval-when-compile
  (require 'ibuf-macs)
  (require 'cl))

;;; Utility functions
(defun ibuffer-delete-alist (key alist)
  "Delete all entries in ALIST that have a key equal to KEY."
  (let (entry)
    (while (setq entry (assoc key alist))
      (setq alist (delete entry alist)))
    alist))

;; borrowed from Gnus
(defun ibuffer-remove-duplicates (list)
  "Return a copy of LIST with duplicate elements removed."
  (let ((new nil)
	(tail list))
    (while tail
      (or (member (car tail) new)
	  (setq new (cons (car tail) new)))
      (setq tail (cdr tail)))
    (nreverse new)))

(defun ibuffer-split-list (ibuffer-split-list-fn ibuffer-split-list-elts)
  (let ((hip-crowd nil)
	(lamers nil))
    (dolist (ibuffer-split-list-elt ibuffer-split-list-elts)
      (if (funcall ibuffer-split-list-fn ibuffer-split-list-elt)
	  (push ibuffer-split-list-elt hip-crowd)
	(push ibuffer-split-list-elt lamers)))
    ;; Too bad Emacs Lisp doesn't have multiple values.
    (list (nreverse hip-crowd) (nreverse lamers))))

(defcustom ibuffer-never-show-predicates nil
  "A list of predicates (a regexp or function) for buffers not to display.
If a regexp, then it will be matched against the buffer's name.
If a function, it will be called with the buffer as an argument, and
should return non-nil if this buffer should not be shown."
  :type '(repeat (choice regexp function))
  :require 'ibuf-ext
  :group 'ibuffer)

(defcustom ibuffer-always-show-predicates nil
  "A list of predicates (a regexp or function) for buffers to always display.
If a regexp, then it will be matched against the buffer's name.
If a function, it will be called with the buffer as an argument, and
should return non-nil if this buffer should be shown.
Note that buffers matching one of these predicates will be shown
regardless of any active filters in this buffer."
  :type '(repeat (choice regexp function))
  :group 'ibuffer)

(defvar ibuffer-tmp-hide-regexps nil
  "A list of regexps which should match buffer names to not show.")

(defvar ibuffer-tmp-show-regexps nil
  "A list of regexps which should match buffer names to always show.")

(defvar ibuffer-auto-buffers-changed nil)

(defcustom ibuffer-saved-filters '(("gnus"
				    ((or (mode . message-mode)
					 (mode . mail-mode)
					 (mode . gnus-group-mode)
					 (mode . gnus-summary-mode)
					 (mode . gnus-article-mode))))
				   ("programming"
				    ((or (mode . emacs-lisp-mode)
					 (mode . cperl-mode)
					 (mode . c-mode)
					 (mode . java-mode)
					 (mode . idl-mode)
					 (mode . lisp-mode)))))

  "An alist of filter qualifiers to switch between.

This variable should look like ((\"STRING\" QUALIFIERS)
                                (\"STRING\" QUALIFIERS) ...), where
QUALIFIERS is a list of the same form as
`ibuffer-filtering-qualifiers'.
See also the variables `ibuffer-filtering-qualifiers',
`ibuffer-filtering-alist', and the functions
`ibuffer-switch-to-saved-filters', `ibuffer-save-filters'."
  :type '(repeat sexp)
  :group 'ibuffer)

(defvar ibuffer-filtering-qualifiers nil
  "A list like (SYMBOL . QUALIFIER) which filters the current buffer list.
See also `ibuffer-filtering-alist'.")

;; This is now frobbed by `define-ibuffer-filter'.
(defvar ibuffer-filtering-alist nil
  "An alist of (SYMBOL DESCRIPTION FUNCTION) which describes a filter.

You most likely do not want to modify this variable directly; see
`define-ibuffer-filter'.

SYMBOL is the symbolic name of the filter.  DESCRIPTION is used when
displaying information to the user.  FUNCTION is given a buffer and
the value of the qualifier, and returns non-nil if and only if the
buffer should be displayed.")

(defcustom ibuffer-filter-format-alist nil
  "An alist which has special formats used when a filter is active.
The contents of this variable should look like:
 ((FILTER (FORMAT FORMAT ...)) (FILTER (FORMAT FORMAT ...)) ...)

For example, suppose that when you add a filter for buffers whose
major mode is `emacs-lisp-mode', you only want to see the mark and the
name of the buffer.  You could accomplish that by adding:
 (mode ((mark \" \" name)))
to this variable."
  :type '(repeat (list :tag "Association" (symbol :tag "Filter")
                       (list :tag "Formats" (repeat (sexp :tag "Format")))))
  :group 'ibuffer)

(defvar ibuffer-cached-filter-formats nil)
(defvar ibuffer-compiled-filter-formats nil)

(defvar ibuffer-filter-groups nil
  "A list like ((\"NAME\" ((SYMBOL . QUALIFIER) ...) ...) which groups buffers.
The SYMBOL should be one from `ibuffer-filtering-alist'.
The QUALIFIER should be the same as QUALIFIER in
`ibuffer-filtering-qualifiers'.")

(defcustom ibuffer-show-empty-filter-groups t
  "If non-nil, then show the names of filter groups which are empty."
  :type 'boolean
  :group 'ibuffer)

(defcustom ibuffer-saved-filter-groups nil
  "An alist of filtering groups to switch between.

This variable should look like ((\"STRING\" QUALIFIERS)
                                (\"STRING\" QUALIFIERS) ...), where
QUALIFIERS is a list of the same form as
`ibuffer-filtering-qualifiers'.

See also the variables `ibuffer-filter-groups',
`ibuffer-filtering-qualifiers', `ibuffer-filtering-alist', and the
functions `ibuffer-switch-to-saved-filter-groups',
`ibuffer-save-filter-groups'."
  :type '(repeat sexp)
  :group 'ibuffer)

(defvar ibuffer-hidden-filter-groups nil
  "A list of filtering groups which are currently hidden.")

(defvar ibuffer-filter-group-kill-ring nil)

(defcustom ibuffer-old-time 72
  "The number of hours before a buffer is considered \"old\"."
  :type '(choice (const :tag "72 hours (3 days)" 72)
 		 (const :tag "48 hours (2 days)" 48)
 		 (const :tag "24 hours (1 day)" 24)
		 (integer :tag "hours"))
  :group 'ibuffer)

(defcustom ibuffer-save-with-custom t
  "If non-nil, then use Custom to save interactively changed variables.
Currently, this only applies to `ibuffer-saved-filters' and
`ibuffer-saved-filter-groups'."
  :type 'boolean
  :group 'ibuffer)

(defun ibuffer-ext-visible-p (buf all &optional ibuffer-buf)
  (or
   (ibuffer-buf-matches-predicates buf ibuffer-tmp-show-regexps)
   (and (not
	 (or
	  (ibuffer-buf-matches-predicates buf ibuffer-tmp-hide-regexps)
	  (ibuffer-buf-matches-predicates buf ibuffer-never-show-predicates)))
	(or all
	    (not
	     (ibuffer-buf-matches-predicates buf ibuffer-maybe-show-predicates)))
	(or ibuffer-view-ibuffer
	    (and ibuffer-buf
		 (not (eq ibuffer-buf buf))))
	(or
	 (ibuffer-included-in-filters-p buf ibuffer-filtering-qualifiers)
	 (ibuffer-buf-matches-predicates buf ibuffer-always-show-predicates)))))

;;;###autoload
(define-minor-mode ibuffer-auto-mode
  "Toggle use of Ibuffer's auto-update facility.
With numeric ARG, enable auto-update if and only if ARG is positive."
  nil nil nil
  (unless (derived-mode-p 'ibuffer-mode)
    (error "This buffer is not in Ibuffer mode"))
  (frame-or-buffer-changed-p 'ibuffer-auto-buffers-changed) ; Initialize state vector
  (add-hook 'post-command-hook 'ibuffer-auto-update-changed))

(defun ibuffer-auto-update-changed ()
  (when (frame-or-buffer-changed-p 'ibuffer-auto-buffers-changed)
    (dolist (buf (buffer-list))
      (ignore-errors
	(with-current-buffer buf
	  (when (and ibuffer-auto-mode
		     (derived-mode-p 'ibuffer-mode))
	    (ibuffer-update nil t)))))))

;;;###autoload
(defun ibuffer-mouse-filter-by-mode (event)
  "Enable or disable filtering by the major mode chosen via mouse."
  (interactive "e")
  (ibuffer-interactive-filter-by-mode event))

;;;###autoload
(defun ibuffer-interactive-filter-by-mode (event-or-point)
  "Enable or disable filtering by the major mode at point."
  (interactive "d")
  (if (eventp event-or-point)
      (posn-set-point (event-end event-or-point))
    (goto-char event-or-point))
  (let ((buf (ibuffer-current-buffer)))
    (if (assq 'mode ibuffer-filtering-qualifiers)
	(setq ibuffer-filtering-qualifiers
	      (ibuffer-delete-alist 'mode ibuffer-filtering-qualifiers))
      (ibuffer-push-filter (cons 'mode (buffer-local-value 'major-mode buf)))))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-mouse-toggle-filter-group (event)
  "Toggle the display status of the filter group chosen with the mouse."
  (interactive "e")
  (ibuffer-toggle-filter-group-1 (save-excursion
				   (mouse-set-point event)
				   (point))))

;;;###autoload
(defun ibuffer-toggle-filter-group ()
  "Toggle the display status of the filter group on this line."
  (interactive)
  (ibuffer-toggle-filter-group-1 (point)))

(defun ibuffer-toggle-filter-group-1 (posn)
  (let ((name (get-text-property posn 'ibuffer-filter-group-name)))
    (unless (stringp name)
      (error "No filtering group name present"))
    (if (member name ibuffer-hidden-filter-groups)
	(setq ibuffer-hidden-filter-groups
	      (delete name ibuffer-hidden-filter-groups))
      (push name ibuffer-hidden-filter-groups))
    (ibuffer-update nil t)))

;;;###autoload
(defun ibuffer-forward-filter-group (&optional count)
  "Move point forwards by COUNT filtering groups."
  (interactive "P")
  (unless count
    (setq count 1))
  (when (> count 0)
    (when (get-text-property (point) 'ibuffer-filter-group-name)
      (goto-char (next-single-property-change
		  (point) 'ibuffer-filter-group-name
		  nil (point-max))))
    (goto-char (next-single-property-change
		(point) 'ibuffer-filter-group-name
		nil (point-max)))
    (ibuffer-forward-filter-group (1- count)))
  (ibuffer-forward-line 0))

;;;###autoload
(defun ibuffer-backward-filter-group (&optional count)
  "Move point backwards by COUNT filtering groups."
  (interactive "P")
  (unless count
    (setq count 1))
  (when (> count 0)
    (when (get-text-property (point) 'ibuffer-filter-group-name)
      (goto-char (previous-single-property-change
		  (point) 'ibuffer-filter-group-name
		  nil (point-min))))
    (goto-char (previous-single-property-change
		(point) 'ibuffer-filter-group-name
		nil (point-min)))
    (ibuffer-backward-filter-group (1- count)))
  (when (= (point) (point-min))
    (goto-char (point-max))
    (ibuffer-backward-filter-group 1))
  (ibuffer-forward-line 0))

;;;###autoload (autoload 'ibuffer-do-shell-command-pipe "ibuf-ext")
(define-ibuffer-op shell-command-pipe (command)
  "Pipe the contents of each marked buffer to shell command COMMAND."
  (:interactive "sPipe to shell command: "
   :opstring "Shell command executed on"
   :modifier-p nil)
  (shell-command-on-region
   (point-min) (point-max) command
   (get-buffer-create "* ibuffer-shell-output*")))

;;;###autoload (autoload 'ibuffer-do-shell-command-pipe-replace "ibuf-ext")
(define-ibuffer-op shell-command-pipe-replace (command)
  "Replace the contents of marked buffers with output of pipe to COMMAND."
  (:interactive "sPipe to shell command (replace): "
   :opstring "Buffer contents replaced in"
   :active-opstring "replace buffer contents in"
   :dangerous t
   :modifier-p t)
  (with-current-buffer buf
    (shell-command-on-region (point-min) (point-max)
			     command nil t)))

;;;###autoload (autoload 'ibuffer-do-shell-command-file "ibuf-ext")
(define-ibuffer-op shell-command-file (command)
  "Run shell command COMMAND separately on files of marked buffers."
  (:interactive "sShell command on buffer's file: "
   :opstring "Shell command executed on"
   :modifier-p nil)
  (shell-command (concat command " "
			 (shell-quote-argument
			  (if buffer-file-name
			      buffer-file-name
			    (make-temp-file
			     (substring (buffer-name) 0 (min 10 (length (buffer-name))))))))))

;;;###autoload (autoload 'ibuffer-do-eval "ibuf-ext")
(define-ibuffer-op eval (form)
  "Evaluate FORM in each of the buffers.
Does not display the buffer during evaluation. See
`ibuffer-do-view-and-eval' for that."
  (:interactive
   (list
    (read-from-minibuffer
     "Eval in buffers (form): "
     nil read-expression-map t 'read-expression-history))
   :opstring "evaluated in"
   :modifier-p :maybe)
  (eval form))

;;;###autoload (autoload 'ibuffer-do-view-and-eval "ibuf-ext")
(define-ibuffer-op view-and-eval (form)
  "Evaluate FORM while displaying each of the marked buffers.
To evaluate a form without viewing the buffer, see `ibuffer-do-eval'."
  (:interactive
   (list
    (read-from-minibuffer
     "Eval viewing in buffers (form): "
     nil read-expression-map t 'read-expression-history))
   :opstring "evaluated in"
   :complex t
   :modifier-p :maybe)
  (let ((ibuffer-buf (current-buffer)))
    (unwind-protect
	(progn
	  (switch-to-buffer buf)
	  (eval form))
      (switch-to-buffer ibuffer-buf))))

;;;###autoload (autoload 'ibuffer-do-rename-uniquely "ibuf-ext")
(define-ibuffer-op rename-uniquely ()
  "Rename marked buffers as with `rename-uniquely'."
  (:opstring "renamed"
   :modifier-p t)
  (rename-uniquely))

;;;###autoload (autoload 'ibuffer-do-revert "ibuf-ext")
(define-ibuffer-op revert ()
  "Revert marked buffers as with `revert-buffer'."
  (:dangerous t
   :opstring "reverted"
   :active-opstring "revert"
   :modifier-p :maybe)
  (revert-buffer t t))

;;;###autoload (autoload 'ibuffer-do-isearch "ibuf-ext")
(define-ibuffer-op ibuffer-do-isearch ()
  "Perform a `isearch-forward' in marked buffers."
  (:interactive ()
   :opstring "searched in"
   :complex t
   :modifier-p :maybe)
  (multi-isearch-buffers (ibuffer-get-marked-buffers)))

;;;###autoload (autoload 'ibuffer-do-isearch-regexp "ibuf-ext")
(define-ibuffer-op ibuffer-do-isearch-regexp ()
  "Perform a `isearch-forward-regexp' in marked buffers."
  (:interactive ()
   :opstring "searched regexp in"
   :complex t
   :modifier-p :maybe)
  (multi-isearch-buffers-regexp (ibuffer-get-marked-buffers)))

;;;###autoload (autoload 'ibuffer-do-replace-regexp "ibuf-ext")
(define-ibuffer-op replace-regexp (from-str to-str)
  "Perform a `replace-regexp' in marked buffers."
  (:interactive
   (let* ((from-str (read-from-minibuffer "Replace regexp: "))
	  (to-str (read-from-minibuffer (concat "Replace " from-str
						" with: "))))
     (list from-str to-str))
   :opstring "replaced in"
   :complex t
   :modifier-p :maybe)
  (save-window-excursion
    (switch-to-buffer buf)
    (save-excursion
      (goto-char (point-min))
      (let ((case-fold-search ibuffer-case-fold-search))
	(while (re-search-forward from-str nil t)
	  (replace-match to-str))))
    t))

;;;###autoload (autoload 'ibuffer-do-query-replace "ibuf-ext")
(define-ibuffer-op query-replace (&rest args)
  "Perform a `query-replace' in marked buffers."
  (:interactive
   (query-replace-read-args "Query replace" t t)
   :opstring "replaced in"
   :complex t
   :modifier-p :maybe)
  (save-window-excursion
    (switch-to-buffer buf)
    (save-excursion
      (let ((case-fold-search ibuffer-case-fold-search))
	(goto-char (point-min))
	(apply #'query-replace args)))
    t))

;;;###autoload (autoload 'ibuffer-do-query-replace-regexp "ibuf-ext")
(define-ibuffer-op query-replace-regexp (&rest args)
  "Perform a `query-replace-regexp' in marked buffers."
  (:interactive
   (query-replace-read-args "Query replace regexp" t t)
   :opstring "replaced in"
   :complex t
   :modifier-p :maybe)
  (save-window-excursion
    (switch-to-buffer buf)
    (save-excursion
      (let ((case-fold-search ibuffer-case-fold-search))
	(goto-char (point-min))
	(apply #'query-replace-regexp args)))
    t))

;;;###autoload (autoload 'ibuffer-do-print "ibuf-ext")
(define-ibuffer-op print ()
  "Print marked buffers as with `print-buffer'."
  (:opstring "printed"
   :modifier-p nil)
  (print-buffer))

;;;###autoload
(defun ibuffer-included-in-filters-p (buf filters)
  (not
   (memq nil ;; a filter will return nil if it failed
	 (mapcar
	  ;; filter should be like (TYPE . QUALIFIER), or
	  ;; (or (TYPE . QUALIFIER) (TYPE . QUALIFIER) ...)
	  #'(lambda (qual)
	      (ibuffer-included-in-filter-p buf qual))
	  filters))))

(defun ibuffer-included-in-filter-p (buf filter)
  (if (eq (car filter) 'not)
      (not (ibuffer-included-in-filter-p-1 buf (cdr filter)))
    (ibuffer-included-in-filter-p-1 buf filter)))

(defun ibuffer-included-in-filter-p-1 (buf filter)
  (not
   (not
    (case (car filter)
      (or
       (memq t (mapcar #'(lambda (x)
			   (ibuffer-included-in-filter-p buf x))
		       (cdr filter))))
      (saved
       (let ((data
	      (assoc (cdr filter)
		     ibuffer-saved-filters)))
	 (unless data
	   (ibuffer-filter-disable)
	   (error "Unknown saved filter %s" (cdr filter)))
	 (ibuffer-included-in-filters-p buf (cadr data))))
      (t
       (let ((filterdat (assq (car filter)
			      ibuffer-filtering-alist)))
	 ;; filterdat should be like (TYPE DESCRIPTION FUNC)
	 ;; just a sanity check
	(unless filterdat
	  (ibuffer-filter-disable)
	  (error "Undefined filter %s" (car filter)))
	(not
	 (not
	  (funcall (caddr filterdat)
		   buf
		   (cdr filter))))))))))

(defun ibuffer-generate-filter-groups (bmarklist &optional noempty nodefault)
  (let ((filter-group-alist (if nodefault
				ibuffer-filter-groups
			      (append ibuffer-filter-groups
				      (list (cons "Default" nil))))))
;;     (dolist (hidden ibuffer-hidden-filter-groups)
;;       (setq filter-group-alist (ibuffer-delete-alist
;; 				   hidden filter-group-alist)))
    (let ((vec (make-vector (length filter-group-alist) nil))
	  (i 0))
      (dolist (filtergroup filter-group-alist)
	(let ((filterset (cdr filtergroup)))
	  (multiple-value-bind (hip-crowd lamers)
	      (values-list
	       (ibuffer-split-list (lambda (bufmark)
				     (ibuffer-included-in-filters-p (car bufmark)
								    filterset))
				   bmarklist))
	    (aset vec i hip-crowd)
	    (incf i)
	    (setq bmarklist lamers))))
      (let (ret)
	(dotimes (j i ret)
	  (let ((bufs (aref vec j)))
	    (unless (and noempty (null bufs))
	      (push (cons (car (nth j filter-group-alist))
			  bufs)
		    ret))))))))

;;;###autoload
(defun ibuffer-filters-to-filter-group (name)
  "Make the current filters into a filtering group."
  (interactive "sName for filtering group: ")
  (when (null ibuffer-filtering-qualifiers)
    (error "No filters in effect"))
  (push (cons name ibuffer-filtering-qualifiers) ibuffer-filter-groups)
  (ibuffer-filter-disable))

;;;###autoload
(defun ibuffer-set-filter-groups-by-mode ()
  "Set the current filter groups to filter by mode."
  (interactive)
  (setq ibuffer-filter-groups
        (mapcar (lambda (mode)
                  (cons (format "%s" mode) `((mode . ,mode))))
                (let ((modes
                       (ibuffer-remove-duplicates
                        (mapcar (lambda (buf)
				  (buffer-local-value 'major-mode buf))
                                (buffer-list)))))
                  (if ibuffer-view-ibuffer
		      modes
		    (delq 'ibuffer-mode modes)))))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-pop-filter-group ()
  "Remove the first filter group."
  (interactive)
  (when (null ibuffer-filter-groups)
    (error "No filter groups active"))
  (setq ibuffer-hidden-filter-groups
	(delete (pop ibuffer-filter-groups)
		ibuffer-hidden-filter-groups))
  (ibuffer-update nil t))

(defun ibuffer-read-filter-group-name (msg &optional nodefault noerror)
  (when (and (not noerror) (null ibuffer-filter-groups))
    (error "No filter groups active"))
  ;; `ibuffer-generate-filter-groups' returns all non-hidden filter
  ;; groups, possibly excluding empty groups or Default.
  ;; We add `ibuffer-hidden-filter-groups' to the list, excluding
  ;; Default if necessary.
  (completing-read msg (nconc
			(ibuffer-generate-filter-groups
			 (ibuffer-current-state-list)
			 (not ibuffer-show-empty-filter-groups)
			 nodefault)
			(if nodefault
			    (remove "Default" ibuffer-hidden-filter-groups)
			  ibuffer-hidden-filter-groups))
		   nil t))

;;;###autoload
(defun ibuffer-decompose-filter-group (group)
  "Decompose the filter group GROUP into active filters."
  (interactive
   (list (ibuffer-read-filter-group-name "Decompose filter group: " t)))
  (let ((data (cdr (assoc group ibuffer-filter-groups))))
    (setq ibuffer-filter-groups (ibuffer-delete-alist
				 group ibuffer-filter-groups)
	  ibuffer-filtering-qualifiers data))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-clear-filter-groups ()
  "Remove all filter groups."
  (interactive)
  (setq ibuffer-filter-groups nil
	ibuffer-hidden-filter-groups nil)
  (ibuffer-update nil t))

(defun ibuffer-current-filter-groups-with-position ()
  (save-excursion
    (goto-char (point-min))
    (let ((pos nil)
	  (result nil))
      (while (and (not (eobp))
		  (setq pos (next-single-property-change
			     (point) 'ibuffer-filter-group-name)))
	(goto-char pos)
	(push (cons (get-text-property (point) 'ibuffer-filter-group-name)
		    pos)
	      result)
	(goto-char (next-single-property-change
		    pos 'ibuffer-filter-group-name)))
      (nreverse result))))

;;;###autoload
(defun ibuffer-jump-to-filter-group (name)
  "Move point to the filter group whose name is NAME."
  (interactive
   (list (ibuffer-read-filter-group-name "Jump to filter group: ")))
  (ibuffer-aif (assoc name (ibuffer-current-filter-groups-with-position))
      (goto-char (cdr it))
    (error "No filter group with name %s" name)))

;;;###autoload
(defun ibuffer-kill-filter-group (name)
  "Kill the filter group named NAME.
The group will be added to `ibuffer-filter-group-kill-ring'."
  (interactive (list (ibuffer-read-filter-group-name "Kill filter group: " t)))
  (when (equal name "Default")
    (error "Can't kill default filter group"))
  (ibuffer-aif (assoc name ibuffer-filter-groups)
      (progn
	(push (copy-tree it) ibuffer-filter-group-kill-ring)
	(setq ibuffer-filter-groups (ibuffer-delete-alist
				     name ibuffer-filter-groups))
	(setq ibuffer-hidden-filter-groups
	      (delete name ibuffer-hidden-filter-groups)))
    (error "No filter group with name \"%s\"" name))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-kill-line (&optional arg interactive-p)
  "Kill the filter group at point.
See also `ibuffer-kill-filter-group'."
  (interactive "P\np")
  (ibuffer-aif (save-excursion
		 (ibuffer-forward-line 0)
		 (get-text-property (point) 'ibuffer-filter-group-name))
      (progn
	(ibuffer-kill-filter-group it))
      (funcall (if interactive-p #'call-interactively #'funcall)
	       #'kill-line arg)))

(defun ibuffer-insert-filter-group-before (newgroup group)
  (let* ((found nil)
	 (pos (let ((groups (mapcar #'car ibuffer-filter-groups))
		    (res 0))
		(while groups
		  (if (equal (car groups) group)
		      (setq found t
			    groups nil)
		    (incf res)
		    (setq groups (cdr groups))))
		res)))
    (cond ((not found)
	   (setq ibuffer-filter-groups
		 (nconc ibuffer-filter-groups (list newgroup))))
	  ((zerop pos)
	   (push newgroup ibuffer-filter-groups))
	  (t
	   (let ((cell (nthcdr pos ibuffer-filter-groups)))
	     (setf (cdr cell) (cons (car cell) (cdr cell)))
	     (setf (car cell) newgroup))))))

;;;###autoload
(defun ibuffer-yank ()
  "Yank the last killed filter group before group at point."
  (interactive)
  (ibuffer-yank-filter-group
   (or (get-text-property (point) 'ibuffer-filter-group-name)
       (get-text-property (point) 'ibuffer-filter-group)
       (error "No filter group at point"))))

;;;###autoload
(defun ibuffer-yank-filter-group (name)
  "Yank the last killed filter group before group named NAME."
  (interactive (list (ibuffer-read-filter-group-name
			"Yank filter group before group: ")))
  (unless ibuffer-filter-group-kill-ring
    (error "The Ibuffer filter group kill-ring is empty"))
  (save-excursion
    (ibuffer-forward-line 0)
    (ibuffer-insert-filter-group-before (pop ibuffer-filter-group-kill-ring)
					name))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-save-filter-groups (name groups)
  "Save all active filter groups GROUPS as NAME.
They are added to `ibuffer-saved-filter-groups'.  Interactively,
prompt for NAME, and use the current filters."
  (interactive
   (if (null ibuffer-filter-groups)
       (error "No filter groups active")
     (list
      (read-from-minibuffer "Save current filter groups as: ")
      ibuffer-filter-groups)))
  (ibuffer-aif (assoc name ibuffer-saved-filter-groups)
      (setcdr it groups)
    (push (cons name groups) ibuffer-saved-filter-groups))
  (ibuffer-maybe-save-stuff))

;;;###autoload
(defun ibuffer-delete-saved-filter-groups (name)
  "Delete saved filter groups with NAME.
They are removed from `ibuffer-saved-filter-groups'."
  (interactive
   (list
    (if (null ibuffer-saved-filter-groups)
	(error "No saved filter groups")
      (completing-read "Delete saved filter group: "
		       ibuffer-saved-filter-groups nil t))))
  (setq ibuffer-saved-filter-groups
	(ibuffer-delete-alist name ibuffer-saved-filter-groups))
  (ibuffer-maybe-save-stuff)
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-switch-to-saved-filter-groups (name)
  "Set this buffer's filter groups to saved version with NAME.
The value from `ibuffer-saved-filter-groups' is used."
  (interactive
   (list
    (if (null ibuffer-saved-filter-groups)
	(error "No saved filters")
      (completing-read "Switch to saved filter group: "
		       ibuffer-saved-filter-groups nil t))))
  (setq ibuffer-filter-groups (cdr (assoc name ibuffer-saved-filter-groups))
	ibuffer-hidden-filter-groups nil)
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-filter-disable ()
  "Disable all filters currently in effect in this buffer."
  (interactive)
  (setq ibuffer-filtering-qualifiers nil
	ibuffer-filter-groups nil)
  (let ((buf (ibuffer-current-buffer)))
    (ibuffer-update nil t)
    (when buf
      (ibuffer-jump-to-buffer (buffer-name buf)))))

;;;###autoload
(defun ibuffer-pop-filter ()
  "Remove the top filter in this buffer."
  (interactive)
  (when (null ibuffer-filtering-qualifiers)
    (error "No filters in effect"))
  (pop ibuffer-filtering-qualifiers)
  (let ((buf (ibuffer-current-buffer)))
    (ibuffer-update nil t)
    (when buf
      (ibuffer-jump-to-buffer (buffer-name buf)))))

(defun ibuffer-push-filter (qualifier)
  "Add QUALIFIER to `ibuffer-filtering-qualifiers'."
  (push qualifier ibuffer-filtering-qualifiers))

;;;###autoload
(defun ibuffer-decompose-filter ()
  "Separate the top compound filter (OR, NOT, or SAVED) in this buffer.

This means that the topmost filter on the filtering stack, which must
be a complex filter like (OR [name: foo] [mode: bar-mode]), will be
turned into two separate filters [name: foo] and [mode: bar-mode]."
  (interactive)
  (when (null ibuffer-filtering-qualifiers)
    (error "No filters in effect"))
  (let ((lim (pop ibuffer-filtering-qualifiers)))
    (case (car lim)
      (or
       (setq ibuffer-filtering-qualifiers (append
					  (cdr lim)
					  ibuffer-filtering-qualifiers)))
      (saved
       (let ((data
	      (assoc (cdr lim)
		     ibuffer-saved-filters)))
	 (unless data
	   (ibuffer-filter-disable)
	   (error "Unknown saved filter %s" (cdr lim)))
	 (setq ibuffer-filtering-qualifiers (append
					    (cadr data)
					    ibuffer-filtering-qualifiers))))
      (not
       (push (cdr lim)
	     ibuffer-filtering-qualifiers))
      (t
       (error "Filter type %s is not compound" (car lim)))))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-exchange-filters ()
  "Exchange the top two filters on the stack in this buffer."
  (interactive)
  (when (< (length ibuffer-filtering-qualifiers)
	   2)
    (error "Need two filters to exchange"))
  (let ((first (pop ibuffer-filtering-qualifiers))
	(second (pop ibuffer-filtering-qualifiers)))
    (push first ibuffer-filtering-qualifiers)
    (push second ibuffer-filtering-qualifiers))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-negate-filter ()
  "Negate the sense of the top filter in the current buffer."
  (interactive)
  (when (null ibuffer-filtering-qualifiers)
    (error "No filters in effect"))
  (let ((lim (pop ibuffer-filtering-qualifiers)))
    (push (if (eq (car lim) 'not)
	      (cdr lim)
	    (cons 'not lim))
	  ibuffer-filtering-qualifiers))
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-or-filter (&optional reverse)
  "Replace the top two filters in this buffer with their logical OR.
If optional argument REVERSE is non-nil, instead break the top OR
filter into parts."
  (interactive "P")
  (if reverse
      (progn
	(when (or (null ibuffer-filtering-qualifiers)
		  (not (eq 'or (caar ibuffer-filtering-qualifiers))))
	  (error "Top filter is not an OR"))
	(let ((lim (pop ibuffer-filtering-qualifiers)))
	  (setq ibuffer-filtering-qualifiers
		(nconc (cdr lim) ibuffer-filtering-qualifiers))))
    (when (< (length ibuffer-filtering-qualifiers) 2)
      (error "Need two filters to OR"))
    ;; If the second filter is an OR, just add to it.
    (let ((first (pop ibuffer-filtering-qualifiers))
	  (second (pop ibuffer-filtering-qualifiers)))
      (if (eq 'or (car second))
	  (push (nconc (list 'or first) (cdr second))
		ibuffer-filtering-qualifiers)
	(push (list 'or first second)
	      ibuffer-filtering-qualifiers))))
  (ibuffer-update nil t))

(defun ibuffer-maybe-save-stuff ()
  (when ibuffer-save-with-custom
    (if (fboundp 'customize-save-variable)
	(progn
	  (customize-save-variable 'ibuffer-saved-filters
				   ibuffer-saved-filters)
	  (customize-save-variable 'ibuffer-saved-filter-groups
				   ibuffer-saved-filter-groups))
      (message "Not saved permanently: Customize not available"))))

;;;###autoload
(defun ibuffer-save-filters (name filters)
  "Save FILTERS in this buffer with name NAME in `ibuffer-saved-filters'.
Interactively, prompt for NAME, and use the current filters."
  (interactive
   (if (null ibuffer-filtering-qualifiers)
       (error "No filters currently in effect")
     (list
      (read-from-minibuffer "Save current filters as: ")
      ibuffer-filtering-qualifiers)))
  (ibuffer-aif (assoc name ibuffer-saved-filters)
      (setcdr it filters)
    (push (list name filters) ibuffer-saved-filters))
  (ibuffer-maybe-save-stuff))

;;;###autoload
(defun ibuffer-delete-saved-filters (name)
  "Delete saved filters with NAME from `ibuffer-saved-filters'."
  (interactive
   (list
    (if (null ibuffer-saved-filters)
	(error "No saved filters")
      (completing-read "Delete saved filters: "
		       ibuffer-saved-filters nil t))))
  (setq ibuffer-saved-filters
	(ibuffer-delete-alist name ibuffer-saved-filters))
  (ibuffer-maybe-save-stuff)
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-add-saved-filters (name)
  "Add saved filters from `ibuffer-saved-filters' to this buffer's filters."
  (interactive
   (list
    (if (null ibuffer-saved-filters)
	(error "No saved filters")
      (completing-read "Add saved filters: "
		       ibuffer-saved-filters nil t))))
  (push (cons 'saved name) ibuffer-filtering-qualifiers)
  (ibuffer-update nil t))

;;;###autoload
(defun ibuffer-switch-to-saved-filters (name)
  "Set this buffer's filters to filters with NAME from `ibuffer-saved-filters'."
  (interactive
   (list
    (if (null ibuffer-saved-filters)
	(error "No saved filters")
      (completing-read "Switch to saved filters: "
		       ibuffer-saved-filters nil t))))
  (setq ibuffer-filtering-qualifiers (list (cons 'saved name)))
  (ibuffer-update nil t))

(defun ibuffer-format-filter-group-data (filter)
  (if (equal filter "Default")
      ""
    (concat "Filter:" (mapconcat #'ibuffer-format-qualifier
				 (cdr (assq filter ibuffer-filter-groups))
				 " "))))

(defun ibuffer-format-qualifier (qualifier)
  (if (eq (car-safe qualifier) 'not)
      (concat " [NOT" (ibuffer-format-qualifier-1 (cdr qualifier)) "]")
    (ibuffer-format-qualifier-1 qualifier)))

(defun ibuffer-format-qualifier-1 (qualifier)
  (case (car qualifier)
    (saved
     (concat " [filter: " (cdr qualifier) "]"))
    (or
     (concat " [OR" (mapconcat #'ibuffer-format-qualifier
			       (cdr qualifier) "") "]"))
    (t
     (let ((type (assq (car qualifier) ibuffer-filtering-alist)))
       (unless qualifier
	 (error "Ibuffer: bad qualifier %s" qualifier))
       (concat " [" (cadr type) ": " (format "%s]" (cdr qualifier)))))))


(defun ibuffer-list-buffer-modes ()
  "Create an alist of buffer modes currently in use.
The list returned will be of the form (\"MODE-NAME\" . MODE-SYMBOL)."
  (let ((bufs (buffer-list))
	(modes)
	(this-mode))
    (while bufs
      (setq this-mode (buffer-local-value 'major-mode (car bufs))
	    bufs (cdr bufs))
      (add-to-list
       'modes
       `(,(symbol-name this-mode) .
	 ,this-mode)))
    modes))


;;; Extra operation definitions

;;;###autoload (autoload 'ibuffer-filter-by-mode "ibuf-ext")
(define-ibuffer-filter mode
  "Toggle current view to buffers with major mode QUALIFIER."
  (:description "major mode"
   :reader
   (intern
    (completing-read "Filter by major mode: " obarray
		     #'(lambda (e)
			 (string-match "-mode$"
				       (symbol-name e)))
		     t
		     (let ((buf (ibuffer-current-buffer)))
		       (if (and buf (buffer-live-p buf))
			   (symbol-name (buffer-local-value 'major-mode buf))
			 "")))))
  (eq qualifier (buffer-local-value 'major-mode buf)))

;;;###autoload (autoload 'ibuffer-filter-by-used-mode "ibuf-ext")
(define-ibuffer-filter used-mode
  "Toggle current view to buffers with major mode QUALIFIER.
Called interactively, this function allows selection of modes
currently used by buffers."
  (:description "major mode in use"
		:reader
		(intern
		 (completing-read "Filter by major mode: "
				  (ibuffer-list-buffer-modes)
				  nil
				  t
				  (let ((buf (ibuffer-current-buffer)))
				    (if (and buf (buffer-live-p buf))
					(symbol-name (buffer-local-value
						      'major-mode buf))
				      "")))))
  (eq qualifier (buffer-local-value 'major-mode buf)))

;;;###autoload (autoload 'ibuffer-filter-by-name "ibuf-ext")
(define-ibuffer-filter name
  "Toggle current view to buffers with name matching QUALIFIER."
  (:description "buffer name"
   :reader (read-from-minibuffer "Filter by name (regexp): "))
  (string-match qualifier (buffer-name buf)))

;;;###autoload (autoload 'ibuffer-filter-by-filename "ibuf-ext")
(define-ibuffer-filter filename
  "Toggle current view to buffers with filename matching QUALIFIER."
  (:description "filename"
   :reader (read-from-minibuffer "Filter by filename (regexp): "))
  (ibuffer-awhen (buffer-local-value 'buffer-file-name buf)
    (string-match qualifier it)))

;;;###autoload (autoload 'ibuffer-filter-by-size-gt  "ibuf-ext")
(define-ibuffer-filter size-gt
  "Toggle current view to buffers with size greater than QUALIFIER."
  (:description "size greater than"
   :reader
   (string-to-number (read-from-minibuffer "Filter by size greater than: ")))
  (> (with-current-buffer buf (buffer-size))
     qualifier))

;;;###autoload (autoload 'ibuffer-filter-by-size-lt  "ibuf-ext")
(define-ibuffer-filter size-lt
   "Toggle current view to buffers with size less than QUALIFIER."
  (:description "size less than"
   :reader
   (string-to-number (read-from-minibuffer "Filter by size less than: ")))
  (< (with-current-buffer buf (buffer-size))
     qualifier))

;;;###autoload (autoload 'ibuffer-filter-by-content "ibuf-ext")
(define-ibuffer-filter content
   "Toggle current view to buffers whose contents match QUALIFIER."
  (:description "content"
   :reader (read-from-minibuffer "Filter by content (regexp): "))
  (with-current-buffer buf
    (save-excursion
      (goto-char (point-min))
      (re-search-forward qualifier nil t))))

;;;###autoload (autoload 'ibuffer-filter-by-predicate "ibuf-ext")
(define-ibuffer-filter predicate
   "Toggle current view to buffers for which QUALIFIER returns non-nil."
  (:description "predicate"
   :reader (read-minibuffer "Filter by predicate (form): "))
  (with-current-buffer buf
    (eval qualifier)))

;;; Sorting

;;;###autoload
(defun ibuffer-toggle-sorting-mode ()
  "Toggle the current sorting mode.
Default sorting modes are:
 Recency - the last time the buffer was viewed
 Name - the name of the buffer
 Major Mode - the name of the major mode of the buffer
 Size - the size of the buffer"
  (interactive)
  (let ((modes (mapcar 'car ibuffer-sorting-functions-alist)))
    (add-to-list 'modes 'recency)
    (setq modes (sort modes 'string-lessp))
    (let ((next (or (car-safe (cdr-safe (memq ibuffer-sorting-mode modes)))
                    (car modes))))
      (setq ibuffer-sorting-mode next)
      (message "Sorting by %s" next)))
  (ibuffer-redisplay t))

;;;###autoload
(defun ibuffer-invert-sorting ()
  "Toggle whether or not sorting is in reverse order."
  (interactive)
  (setq ibuffer-sorting-reversep (not ibuffer-sorting-reversep))
  (message "Sorting order %s"
	   (if ibuffer-sorting-reversep
	       "reversed"
	     "normal"))
  (ibuffer-redisplay t))

;;;###autoload (autoload 'ibuffer-do-sort-by-major-mode "ibuf-ext")
(define-ibuffer-sorter major-mode
  "Sort the buffers by major modes.
Ordering is lexicographic."
  (:description "major mode")
  (string-lessp (downcase
		 (symbol-name (buffer-local-value 'major-mode (car a))))
		(downcase
		 (symbol-name (buffer-local-value 'major-mode (car b))))))

;;;###autoload (autoload 'ibuffer-do-sort-by-mode-name "ibuf-ext")
(define-ibuffer-sorter mode-name
  "Sort the buffers by their mode name.
Ordering is lexicographic."
  (:description "major mode name")
  (string-lessp (downcase
		 (with-current-buffer
		     (car a)
		   (format-mode-line mode-name)))
		(downcase
		 (with-current-buffer
		     (car b)
		   (format-mode-line mode-name)))))

;;;###autoload (autoload 'ibuffer-do-sort-by-alphabetic "ibuf-ext")
(define-ibuffer-sorter alphabetic
  "Sort the buffers by their names.
Ordering is lexicographic."
  (:description "buffer name")
  (string-lessp
   (buffer-name (car a))
   (buffer-name (car b))))

;;;###autoload (autoload 'ibuffer-do-sort-by-size "ibuf-ext")
(define-ibuffer-sorter size
 "Sort the buffers by their size."
  (:description "size")
  (< (with-current-buffer (car a)
       (buffer-size))
     (with-current-buffer (car b)
       (buffer-size))))

;;;###autoload (autoload 'ibuffer-do-sort-by-filename/process "ibuf-ext")
(define-ibuffer-sorter filename/process
 "Sort the buffers by their file name/process name."
  (:description "file name")
  (string-lessp
   ;; FIXME: For now just compare the file name and the process name
   ;; (if it exists).  Is there a better way to do this?
   (or (buffer-file-name (car a))
       (let ((pr-a (get-buffer-process (car a))))
	 (and (processp pr-a) (process-name pr-a))))
   (or (buffer-file-name (car b))
       (let ((pr-b (get-buffer-process (car b))))
	 (and (processp pr-b) (process-name pr-b))))))

;;; Functions to emulate bs.el

;;;###autoload
(defun ibuffer-bs-show ()
  "Emulate `bs-show' from the bs.el package."
  (interactive)
  (ibuffer t "*Ibuffer-bs*" '((filename . ".*")) nil t)
  (define-key (current-local-map) "a" 'ibuffer-bs-toggle-all))

(defun ibuffer-bs-toggle-all ()
  "Emulate `bs-toggle-show-all' from the bs.el package."
  (interactive)
  (if ibuffer-filtering-qualifiers
      (ibuffer-pop-filter)
    (progn (ibuffer-push-filter '(filename . ".*"))
	   (ibuffer-update nil t))))

;;; Handy functions

;;;###autoload
(defun ibuffer-add-to-tmp-hide (regexp)
  "Add REGEXP to `ibuffer-tmp-hide-regexps'.
This means that buffers whose name matches REGEXP will not be shown
for this Ibuffer session."
  (interactive
   (list
    (read-from-minibuffer "Never show buffers matching: "
			  (regexp-quote (buffer-name (ibuffer-current-buffer t))))))
  (push regexp ibuffer-tmp-hide-regexps))

;;;###autoload
(defun ibuffer-add-to-tmp-show (regexp)
  "Add REGEXP to `ibuffer-tmp-show-regexps'.
This means that buffers whose name matches REGEXP will always be shown
for this Ibuffer session."
  (interactive
   (list
    (read-from-minibuffer "Always show buffers matching: "
			  (regexp-quote (buffer-name (ibuffer-current-buffer t))))))
  (push regexp ibuffer-tmp-show-regexps))

;;;###autoload
(defun ibuffer-forward-next-marked (&optional count mark direction)
  "Move forward by COUNT marked buffers (default 1).

If MARK is non-nil, it should be a character denoting the type of mark
to move by.  The default is `ibuffer-marked-char'.

If DIRECTION is non-nil, it should be an integer; negative integers
mean move backwards, non-negative integers mean move forwards."
  (interactive "P")
  (unless count
    (setq count 1))
  (unless mark
    (setq mark ibuffer-marked-char))
  (unless direction
    (setq direction 1))
  ;; Skip the title
  (ibuffer-forward-line 0)
  (let ((opos (point)))
    (ibuffer-forward-line direction)
    (while (not (or (= (point) opos)
		    (eq (ibuffer-current-mark) mark)))
      (ibuffer-forward-line direction))
    (when (and (= (point) opos)
	       (not (eq (ibuffer-current-mark) mark)))
      (error "No buffers with mark %c" mark))))

;;;###autoload
(defun ibuffer-backwards-next-marked (&optional count mark)
   "Move backwards by COUNT marked buffers (default 1).

If MARK is non-nil, it should be a character denoting the type of mark
to move by.  The default is `ibuffer-marked-char'."
   (interactive "P")
   (ibuffer-forward-next-marked count mark -1))

;;;###autoload
(defun ibuffer-do-kill-lines ()
  "Hide all of the currently marked lines."
  (interactive)
  (if (= (ibuffer-count-marked-lines) 0)
      (message "No buffers marked; use 'm' to mark a buffer")
    (let ((count
	   (ibuffer-map-marked-lines
	    #'(lambda (_buf _mark)
		'kill))))
      (message "Killed %s lines" count))))

;;;###autoload
(defun ibuffer-jump-to-buffer (name)
  "Move point to the buffer whose name is NAME.

If called interactively, prompt for a buffer name and go to the
corresponding line in the Ibuffer buffer.  If said buffer is in a
hidden group filter, open it.

If `ibuffer-jump-offer-only-visible-buffers' is non-nil, only offer
visible buffers in the completion list.  Calling the command with
a prefix argument reverses the meaning of that variable."
  (interactive (list
		(let ((only-visible ibuffer-jump-offer-only-visible-buffers))
		  (when current-prefix-arg
		    (setq only-visible (not only-visible)))
		  (if only-visible
		      (let ((table (mapcar #'(lambda (x)
					       (buffer-name (car x)))
					   (ibuffer-current-state-list))))
			(when (null table)
			  (error "No buffers!"))
			(completing-read "Jump to buffer: "
					 table nil t))
		    (read-buffer "Jump to buffer: " nil t)))))
  (when (not (string= "" name))
    (let (buf-point)
      ;; Blindly search for our buffer: it is very likely that it is
      ;; not in a hidden filter group.
      (ibuffer-map-lines #'(lambda (buf _marks)
			     (when (string= (buffer-name buf) name)
			       (setq buf-point (point))
			       nil))
			 t nil)
      (when (and
	     (null buf-point)
	     (not (null ibuffer-hidden-filter-groups)))
	;; We did not find our buffer.  It must be in a hidden filter
	;; group, so go through all hidden filter groups to find it.
	(catch 'found
	  (dolist (group ibuffer-hidden-filter-groups)
	    (ibuffer-jump-to-filter-group group)
	    (ibuffer-toggle-filter-group)
	    (ibuffer-map-lines #'(lambda (buf _marks)
				   (when (string= (buffer-name buf) name)
				     (setq buf-point (point))
				     nil))
			       t group)
	    (if buf-point
		(throw 'found nil)
	      (ibuffer-toggle-filter-group)))))
      (if (null buf-point)
	  ;; Still not found even though we expanded all hidden filter
	  ;; groups: that must be because it's hidden by predicate:
	  ;; we won't bother trying to display it.
	  (error "No buffer with name %s" name)
	(goto-char buf-point)))))

(declare-function diff-sentinel "diff"
		  (code &optional old-temp-file new-temp-file))

(defun ibuffer-diff-buffer-with-file-1 (buffer)
  (let ((bufferfile (buffer-local-value 'buffer-file-name buffer))
	(tempfile (make-temp-file "buffer-content-")))
    (when bufferfile
      (unwind-protect
	  (progn
	    (with-current-buffer buffer
	      (write-region nil nil tempfile nil 'nomessage))
	    (let* ((old (expand-file-name bufferfile))
		   (new (expand-file-name tempfile))
		   (oldtmp (file-local-copy old))
		   (newtmp (file-local-copy new))
		   (switches diff-switches)
		   (command
		    (mapconcat
		     'identity
		     `(,diff-command
		       ;; Use explicitly specified switches
		       ,@(if (listp switches) switches (list switches))
		       ,@(if (or old new)
			     (list "-L" (shell-quote-argument old)
				   "-L" (shell-quote-argument
					 (format "Buffer %s" (buffer-name buffer)))))
		       ,(shell-quote-argument (or oldtmp old))
		       ,(shell-quote-argument (or newtmp new)))
		     " ")))
	      (let ((inhibit-read-only t))
		(insert command "\n")
		(diff-sentinel
		 (call-process shell-file-name nil
			       (current-buffer) nil
			       shell-command-switch command)))
	      (insert "\n"))))
      (sit-for 0)
      (when (file-exists-p tempfile)
	(delete-file tempfile)))))

;;;###autoload
(defun ibuffer-diff-with-file ()
  "View the differences between marked buffers and their associated files.
If no buffers are marked, use buffer at point.
This requires the external program \"diff\" to be in your `exec-path'."
  (interactive)
  (require 'diff)
  (let ((marked-bufs (ibuffer-get-marked-buffers)))
    (when (null marked-bufs)
      (setq marked-bufs (list (ibuffer-current-buffer t))))
    (with-current-buffer (get-buffer-create "*Ibuffer Diff*")
      (setq buffer-read-only nil)
      (buffer-disable-undo (current-buffer))
      (erase-buffer)
      (buffer-enable-undo (current-buffer))
      (diff-mode)
      (dolist (buf marked-bufs)
	(unless (buffer-live-p buf)
	  (error "Buffer %s has been killed" buf))
	(ibuffer-diff-buffer-with-file-1 buf))
      (setq buffer-read-only t)))
  (switch-to-buffer "*Ibuffer Diff*"))

;;;###autoload
(defun ibuffer-copy-filename-as-kill (&optional arg)
  "Copy filenames of marked buffers into the kill ring.

The names are separated by a space.
If a buffer has no filename, it is ignored.

With no prefix arg, use the filename sans its directory of each marked file.
With a zero prefix arg, use the complete filename of each marked file.
With \\[universal-argument], use the filename of each marked file relative
to `ibuffer-default-directory' if non-nil, otherwise `default-directory'.

You can then feed the file name(s) to other commands with \\[yank]."
  (interactive "p")
  (if (zerop (ibuffer-count-marked-lines))
      (message "No buffers marked; use 'm' to mark a buffer")
    (let ((ibuffer-copy-filename-as-kill-result "")
	  (type (cond ((zerop arg)
		       'full)
		      ((= arg 4)
		       'relative)
		      (t
		       'name))))
      (ibuffer-map-marked-lines
       #'(lambda (buf _mark)
	   (setq ibuffer-copy-filename-as-kill-result
		 (concat ibuffer-copy-filename-as-kill-result
			 (let ((name (buffer-file-name buf)))
			   (if name
			       (case type
				 (full
				  name)
				 (relative
				  (file-relative-name
				   name (or ibuffer-default-directory
					    default-directory)))
				 (t
				  (file-name-nondirectory name)))
			     ""))
			 " "))))
      (kill-new ibuffer-copy-filename-as-kill-result))))

(defun ibuffer-mark-on-buffer (func &optional ibuffer-mark-on-buffer-mark group)
  (let ((count
	 (ibuffer-map-lines
	  #'(lambda (buf _mark)
	      (when (funcall func buf)
		(ibuffer-set-mark-1 (or ibuffer-mark-on-buffer-mark
					ibuffer-marked-char))
		t))
	  nil
	  group)))
    (ibuffer-redisplay t)
    (unless (eq ibuffer-mark-on-buffer-mark ?\s)
      (message "Marked %s buffers" count))))

;;;###autoload
(defun ibuffer-mark-by-name-regexp (regexp)
  "Mark all buffers whose name matches REGEXP."
  (interactive "sMark by name (regexp): ")
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (string-match regexp (buffer-name buf)))))

;;;###autoload
(defun ibuffer-mark-by-mode-regexp (regexp)
  "Mark all buffers whose major mode matches REGEXP."
  (interactive "sMark by major mode (regexp): ")
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (with-current-buffer buf
	 (string-match regexp (format-mode-line mode-name nil nil buf))))))

;;;###autoload
(defun ibuffer-mark-by-file-name-regexp (regexp)
  "Mark all buffers whose file name matches REGEXP."
  (interactive "sMark by file name (regexp): ")
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (let ((name (or (buffer-file-name buf)
		       (with-current-buffer buf
			 (and
			  (boundp 'dired-directory)
			  (stringp dired-directory)
			  dired-directory)))))
	 (when name
	   (string-match regexp name))))))

;;;###autoload
(defun ibuffer-mark-by-mode (mode)
  "Mark all buffers whose major mode equals MODE."
  (interactive
   (list (intern (completing-read "Mark by major mode: " obarray
				  #'(lambda (e)
				      ;; kind of a hack...
                                      (and (fboundp e)
                                           (string-match "-mode$"
                                                         (symbol-name e))))
				  t
				  (let ((buf (ibuffer-current-buffer)))
				    (if (and buf (buffer-live-p buf))
					(with-current-buffer buf
					  (cons (symbol-name major-mode)
						0))
				      ""))))))
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (eq (buffer-local-value 'major-mode buf) mode))))

;;;###autoload
(defun ibuffer-mark-modified-buffers ()
  "Mark all modified buffers."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf) (buffer-modified-p buf))))

;;;###autoload
(defun ibuffer-mark-unsaved-buffers ()
  "Mark all modified buffers that have an associated file."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf) (and (buffer-local-value 'buffer-file-name buf)
			(buffer-modified-p buf)))))

;;;###autoload
(defun ibuffer-mark-dissociated-buffers ()
  "Mark all buffers whose associated file does not exist."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (with-current-buffer buf
	 (or
	  (and buffer-file-name
	       (not (file-exists-p buffer-file-name)))
	  (and (eq major-mode 'dired-mode)
	       (boundp 'dired-directory)
	       (stringp dired-directory)
	       (not (file-exists-p (file-name-directory dired-directory)))))))))

;;;###autoload
(defun ibuffer-mark-help-buffers ()
  "Mark buffers like *Help*, *Apropos*, *Info*."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (with-current-buffer buf
	 (memq major-mode ibuffer-help-buffer-modes)))))

;;;###autoload
(defun ibuffer-mark-compressed-file-buffers ()
  "Mark buffers whose associated file is compressed."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (with-current-buffer buf
	 (and buffer-file-name
	      (string-match ibuffer-compressed-file-name-regexp
			   buffer-file-name))))))

;;;###autoload
(defun ibuffer-mark-old-buffers ()
  "Mark buffers which have not been viewed in `ibuffer-old-time' hours."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf)
       (with-current-buffer buf
	 ;; hacked from midnight.el
	 (when buffer-display-time
	   (let* ((tm (current-time))
		  (now (+ (* (float (ash 1 16)) (car tm))
			  (float (cadr tm)) (* 0.0000001 (caddr tm))))
		  (then (+ (* (float (ash 1 16))
			      (car buffer-display-time))
			   (float (cadr buffer-display-time))
			   (* 0.0000001 (caddr buffer-display-time)))))
	     (> (- now then) (* 60 60 ibuffer-old-time))))))))

;;;###autoload
(defun ibuffer-mark-special-buffers ()
  "Mark all buffers whose name begins and ends with '*'."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf) (string-match "^\\*.+\\*$"
				 (buffer-name buf)))))

;;;###autoload
(defun ibuffer-mark-read-only-buffers ()
  "Mark all read-only buffers."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf) (buffer-local-value 'buffer-read-only buf))))

;;;###autoload
(defun ibuffer-mark-dired-buffers ()
  "Mark all `dired' buffers."
  (interactive)
  (ibuffer-mark-on-buffer
   #'(lambda (buf) (eq (buffer-local-value 'major-mode buf) 'dired-mode))))

;;;###autoload
(defun ibuffer-do-occur (regexp &optional nlines)
  "View lines which match REGEXP in all marked buffers.
Optional argument NLINES says how many lines of context to display: it
defaults to one."
  (interactive (occur-read-primary-args))
  (if (or (not (integerp nlines))
	  (< nlines 0))
      (setq nlines 0))
  (when (zerop (ibuffer-count-marked-lines))
    (ibuffer-set-mark ibuffer-marked-char))
  (let ((ibuffer-do-occur-bufs nil))
    ;; Accumulate a list of marked buffers
    (ibuffer-map-marked-lines
     #'(lambda (buf _mark)
	 (push buf ibuffer-do-occur-bufs)))
    (occur-1 regexp nlines ibuffer-do-occur-bufs)))

(provide 'ibuf-ext)

;; Local Variables:
;; generated-autoload-file: "ibuffer.el"
;; End:

;;; ibuf-ext.el ends here