(function): Use restricted-sexp as parent.

[bpt/emacs.git] / lisp / battery.el

;;; battery.el --- display battery status information

;; Copyright (C) 1997, 1998, 2000, 2001, 2003, 2004
;;           Free Software Foundation, Inc.

;; Author: Ralph Schleicher <rs@nunatak.allgaeu.org>
;; Keywords: hardware

;; 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 2, 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; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; There is at present support for interpreting the new `/proc/apm'
;; file format of Linux version 1.3.58 or newer and for the `/proc/acpi/'
;; directory structure of Linux 2.4.20 and 2.6.

;;; Code:

(require 'timer)
(eval-when-compile (require 'cl))

\f
(defgroup battery nil
  "Display battery status information."
  :prefix "battery-"
  :group 'hardware)

(defcustom battery-status-function
  (cond ((and (eq system-type 'gnu/linux)
	      (file-readable-p "/proc/apm"))
	 'battery-linux-proc-apm)
	((and (eq system-type 'gnu/linux)
	      (file-directory-p "/proc/acpi/battery"))
	 'battery-linux-proc-acpi))
  "*Function for getting battery status information.
The function has to return an alist of conversion definitions.
Its cons cells are of the form

    (CONVERSION . REPLACEMENT-TEXT)

CONVERSION is the character code of a \"conversion specification\"
introduced by a `%' character in a control string."
  :type '(choice (const nil) function)
  :group 'battery)

(defcustom battery-echo-area-format
  (cond ((eq battery-status-function 'battery-linux-proc-apm)
	 "Power %L, battery %B (%p%% load, remaining time %t)")
	((eq battery-status-function 'battery-linux-proc-acpi)
	 "Power %L, battery %B at %r (%p%% load, remaining time %t)"))
  "*Control string formatting the string to display in the echo area.
Ordinary characters in the control string are printed as-is, while
conversion specifications introduced by a `%' character in the control
string are substituted as defined by the current value of the variable
`battery-status-function'."
  :type '(choice string (const nil))
  :group 'battery)

(defvar battery-mode-line-string nil
  "String to display in the mode line.")

(defcustom battery-mode-line-format
  (cond ((eq battery-status-function 'battery-linux-proc-apm)
	 " [%b%p%%]")
	((eq battery-status-function 'battery-linux-proc-acpi)