* Support for ACPI has been added to battery.el.
  Patch: battery-acpi-support.diff
  Provided-by: Mario Lang <mlang@debian.org>
  Date: Fri, 26 Sep 2003 15:30:43 +0200
  Added-by: Jerome Marant <jerome@debian.org>
  Status: appears to be incorporated upstream

diff -urNad /home/jerome/pkg/emacs21/svn/emacs/lisp/battery.el emacs/lisp/battery.el
--- /home/jerome/pkg/emacs21/svn/emacs/lisp/battery.el	2003-09-26 19:57:43.000000000 +0200
+++ emacs/lisp/battery.el	2003-09-28 17:19:22.000000000 +0200
@@ -42,7 +42,10 @@
 (defcustom battery-status-function
   (cond ((and (eq system-type 'gnu/linux)
 	      (file-readable-p "/proc/apm"))
-	 'battery-linux-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
@@ -56,7 +59,9 @@
 
 (defcustom battery-echo-area-format
   (cond ((eq battery-status-function 'battery-linux-proc-apm)
-	 "Power %L, battery %B (%p%% load, remaining time %t)"))
+	 "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
@@ -70,7 +75,9 @@
 
 (defcustom battery-mode-line-format
   (cond ((eq battery-status-function 'battery-linux-proc-apm)
-	 " [%b%p%%]"))
+	 " [%b%p%%]")
+	((eq battery-status-function 'battery-linux-proc-acpi)
+	 " [%b%p%%,%d°C]"))
   "*Control string formatting the string to display in the mode line.
 Ordinary characters in the control string are printed as-is, while
 conversion specifications introduced by a `%' character in the control
@@ -217,6 +224,122 @@
 	  (cons ?h (or (and hours (number-to-string hours)) "N/A"))
 	  (cons ?t (or remaining-time "N/A")))))
 
+
+;;; `/proc/acpi/' interface for Linux.
+
+(defun battery-linux-proc-acpi ()
+  "Get ACPI status information from Linux kernel.
+This function works only with the new `/proc/acpi/' format introduced
+in Linux version 2.4.20 and 2.6.0.
+
+The following %-sequences are provided:
+%c Current capacity (mAh)
+%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 in minutes
+%h Remaining time in hours
+%t Remaining time in the form `h:min'"
+  (let (capacity design-capacity rate rate-type charging-state warn low
+		 minutes hours)
+    ;; ACPI provides information about each battery present in the system in
+    ;; a separate subdirectory.  We are going to merge the available
+    ;; information together since displaying for a variable amount of
+    ;; batteries seems overkill for format-strings.
+    (mapc
+     (lambda (dir)
+       (with-temp-buffer
+	 (battery-insert-file-contents (expand-file-name "state" dir))
+	 (when (re-search-forward "present: +yes$" nil t)
+	   (and (re-search-forward "charging state: +\\(.*\\)$" nil t)
+		(or (null charging-state) (string= charging-state
+						   "unknown"))
+		;; On most multi-battery systems, most of the time only one
+		;; battery is "charging"/"discharging", the others are
+		;; "unknown".
+		(setq charging-state (match-string 1)))
+	   (when (re-search-forward "present rate: +\\([0-9]+\\) \\(m[AW]\\)$"
+				    nil t)
+	     (setq rate (+ (or rate 0) (string-to-int (match-string 1)))
+		   rate-type (or (and rate-type
+				      (if (string= rate-type (match-string 2))
+					  rate-type
+					(error
+					 "Inconsistent rate types (%s vs. %s)"
+					 rate-type (match-string 2))))
+				 (match-string 2))))
+	   (when (re-search-forward "remaining capacity: +\\([0-9]+\\) m[AW]h$"
+				    nil t)
+	     (setq capacity
+		   (+ (or capacity 0) (string-to-int (match-string 1))))))
+	 (goto-char (point-max))
+	 (battery-insert-file-contents (expand-file-name "info" dir))
+	 (when (re-search-forward "present: +yes$" nil t)
+	   (when (re-search-forward "design capacity: +\\([0-9]+\\) m[AW]h$"
+				    nil t)
+	     (setq design-capacity (+ (or design-capacity 0)
+				      (string-to-int (match-string 1)))))
+	   (when (re-search-forward "design capacity warning: +\\([0-9]+\\) m[AW]h$"
+				    nil t)
+	     (setq warn (+ (or warn 0) (string-to-int (match-string 1)))))
+	   (when (re-search-forward "design capacity low: +\\([0-9]+\\) m[AW]h$"
+				    nil t)
+	     (setq low (+ (or low 0)
+			  (string-to-int (match-string 1))))))))
+     (directory-files "/proc/acpi/battery/" t "BAT"))
+    (and capacity rate
+	 (setq minutes (if (zerop rate) 0
+			 (floor (* (/ (float (if (string= charging-state
+							  "charging")
+						 (- design-capacity capacity)
+					       capacity)) rate) 60)))
+	       hours (/ minutes 60)))
+    (list (cons ?c (or (and capacity (number-to-string capacity)) "N/A"))
+	  (cons ?L (or (when (file-exists-p "/proc/acpi/ac_adapter/AC/state")
+			 (with-temp-buffer
+			   (battery-insert-file-contents
+			    "/proc/acpi/ac_adapter/AC/state")
+			   (when (re-search-forward "state: +\\(.*\\)$" nil t)
+			     (match-string 1))))
+		       "N/A"))
+	  (cons ?d (or (when (file-exists-p
+			      "/proc/acpi/thermal_zone/THRM/temperature")
+			 (with-temp-buffer
+			   (battery-insert-file-contents
+			    "/proc/acpi/thermal_zone/THRM/temperature")
+			   (when (re-search-forward
+				  "temperature: +\\([0-9]+\\) C$" nil t)
+			     (match-string 1))))
+		       (when (file-exists-p
+			      "/proc/acpi/thermal_zone/THM/temperature")
+			 (with-temp-buffer
+			   (battery-insert-file-contents
+			    "/proc/acpi/thermal_zone/THM/temperature")
+			   (when (re-search-forward
+				  "temperature: +\\([0-9]+\\) C$" nil t)
+			     (match-string 1))))
+		       "N/A"))
+	  (cons ?r (or (and rate (concat (number-to-string rate) " "
+					 rate-type)) "N/A"))
+	  (cons ?B (or charging-state "N/A"))
+	  (cons ?b (or (and (string= charging-state "charging") "+")
+		       (and low (< capacity low) "!")
+	               (and warn (< capacity warn) "-")
+	               ""))
+	  (cons ?h (or (and hours (number-to-string hours)) "N/A"))
+	  (cons ?m (or (and minutes (number-to-string minutes)) "N/A"))
+	  (cons ?t (or (and minutes
+			    (format "%d:%02d" hours (- minutes (* 60 hours))))
+		       "N/A"))
+	  (cons ?p (or (and design-capacity capacity
+			    (number-to-string
+			     (floor (/ capacity
+				       (/ (float design-capacity) 100)))))
+		       "N/A")))))
+
 
 ;;; Private functions.