(battery-status-function): Use w32-battery-status on Windows.

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

;;; battery.el --- display battery status information  -*- coding: iso-8859-1 -*-

;; Copyright (C) 1997, 1998, 2000, 2001, 2002, 2003, 2004,
;;   2005, 2006, 2007, 2008 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 3, 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., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;; There is at present support for GNU/Linux, OS X and Windows.  This
;; library supports both the `/proc/apm' file format of Linux version
;; 1.3.58 or newer and the `/proc/acpi/' directory structure of Linux
;; 2.4.20 and 2.6.  Darwin (OS X) is supported by using the `pmset'
;; program.  Windows is supported by the GetSystemPowerStatus API call.

;;; 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)
	((and (eq system-type 'darwin)
	      (condition-case nil
		  (with-temp-buffer
		    (and (eq (call-process "pmset" nil t nil "-g" "ps") 0)
			 (> (buffer-size) 0)))
		(error nil)))
	 'battery-pmset)
	((eq system-type 'windows-nt)
	 'w32-battery-status))
  "*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-acpi)
	 "Power %L, battery %B at %r (%p%% load, remaining time %t)")
	((eq battery-status-function 'battery-pmset)
	 "%L power, battery %B (%p%% load, remaining time %t)")
	(battery-status-function
	 "Power %L, battery %B (%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'.  Here are the ones generally available:
%c Current capacity (mAh or mWh)
%r Current rate of charge or discharge
%B Battery status (verbose)
%b Battery status: empty means high, `-' means low,
   `!' means critical, and `+' means charging
%d Temperature (in degrees Celsius)
%L AC line status (verbose)
%p Battery load percentage
%m Remaining time (to charge or discharge) in minutes
%h Remaining time (to charge or discharge) in hours
%t Remaining time (to charge or discharge) in the form `h:min'"
  :type '(choice string (const nil))
  :group 'battery)

(defvar battery-mode-line-string nil
  "String to display in the mode line.")
;;;###autoload (put 'battery-mode-line-string 'risky-local-variable t)

(defcustom battery-mode-line-format
  (cond ((eq battery-status-function 'battery-linux-proc-acpi)