X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/7ff974482e2c90a827846675de48dd7235ebee14..409cc4a3ea9e7461572a04f021ff3993e9a516f6:/lisp/time.el

diff --git a/lisp/time.el b/lisp/time.el
index 14a6a17d39..3929fdcc65 100644
--- a/lisp/time.el
+++ b/lisp/time.el
@@ -1,6 +1,7 @@
-;;; time.el --- display time and load in mode line of Emacs.
+;;; time.el --- display time, load and mail indicator in mode line of Emacs -*-coding: utf-8 -*-
 
-;; Copyright (C) 1985, 1986, 1987, 1993, 1994 Free Software Foundation, Inc.
+;; Copyright (C) 1985, 1986, 1987, 1993, 1994, 1996, 2000, 2001, 2002,
+;;   2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
 
 ;; Maintainer: FSF
 
@@ -8,7 +9,7 @@
 
 ;; 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)
+;; 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,
@@ -17,38 +18,92 @@
 ;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; 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:
 
-;;; Facilities to display current time/date and a new-mail indicator
-;;; in the Emacs mode line.  The single entry point is `display-time'.
+;; Facilities to display current time/date and a new-mail indicator
+;; in the Emacs mode line.  The single entry point is `display-time'.
 
 ;;; Code:
 
-(defvar display-time-mail-file nil
+(defgroup display-time nil
+  "Display time and load in mode line of Emacs."
+  :group 'mode-line
+  :group 'mail)
+
+
+(defcustom display-time-mail-file nil
   "*File name of mail inbox file, for indicating existence of new mail.
-Non-nil and not a string means don't check for mail.  nil means use
-default, which is system-dependent, and is the same as used by Rmail.")
+Non-nil and not a string means don't check for mail; nil means use
+default, which is system-dependent, and is the same as used by Rmail."
+  :type '(choice (const :tag "None" none)
+		 (const :tag "Default" nil)
+		 (file :format "%v"))
+  :group 'display-time)
+
+(defcustom display-time-mail-directory nil
+  "*Name of mail inbox directory, for indicating existence of new mail.
+Any nonempty regular file in the directory is regarded as newly arrived mail.
+If nil, do not check a directory for arriving mail."
+  :type '(choice (const :tag "None" nil)
+		 (directory :format "%v"))
+  :group 'display-time)
+
+(defcustom display-time-mail-function nil
+  "*Function to call, for indicating existence of new mail.
+If nil, that means use the default method: check that the file
+specified by `display-time-mail-file' is nonempty or that the
+directory `display-time-mail-directory' contains nonempty files."
+  :type '(choice (const :tag "Default" nil)
+		 (function))
+  :group 'display-time)
+
+(defcustom display-time-default-load-average 0
+  "*Which load average value will be shown in the mode line.
+Almost every system can provide values of load for past 1 minute, past 5 or
+past 15 minutes.  The default is to display 1 minute load average."
+  :type '(choice (const :tag "1 minute load" 0)
+		 (const :tag "5 minutes load" 1)
+		 (const :tag "15 minutes load" 2)
+		 (const :tag "None" nil))
+  :group 'display-time)
+
+(defvar display-time-load-average nil
+  "Load average currently being shown in mode line.")
+
+(defcustom display-time-load-average-threshold 0.1
+  "*Load-average values below this value won't be shown in the mode line."
+  :type 'number
+  :group 'display-time)
 
 ;;;###autoload
-(defvar display-time-day-and-date nil "\
-*Non-nil means \\[display-time] should display day and date as well as time.")
+(defcustom display-time-day-and-date nil "\
+*Non-nil means \\[display-time] should display day and date as well as time."
+  :type 'boolean
+  :group 'display-time)
 
-(defvar display-time-process nil)
+(defvar display-time-timer nil)
 
-(defvar display-time-interval 60
-  "*Seconds between updates of time in the mode line.")
+(defcustom display-time-interval 60
+  "*Seconds between updates of time in the mode line."
+  :type 'integer
+  :group 'display-time)
 
-(defvar display-time-24hr-format nil
+(defcustom display-time-24hr-format nil
   "*Non-nil indicates time should be displayed as hh:mm, 0 <= hh <= 23.
-Nil means 1 <= hh <= 12, and an AM/PM suffix is used.")
+A value of nil means 1 <= hh <= 12, and an AM/PM suffix is used."
+  :type 'boolean
+  :group 'display-time)
 
 (defvar display-time-string nil)
 
-(defvar display-time-hook nil
-  "* List of functions to be called when the time is updated on the mode line.")
+(defcustom display-time-hook nil
+  "*List of functions to be called when the time is updated on the mode line."
+  :type 'hook
+  :group 'display-time)
 
 (defvar display-time-server-down-time nil
    "Time when mail file's file system was recorded to be down.
@@ -56,53 +111,103 @@ If that file system seems to be up, the value is nil.")
 
 ;;;###autoload
 (defun display-time ()
-  "Display current time, load level, and mail flag in mode line of each buffer.
-Updates automatically every minute.
+  "Enable display of time, load level, and mail flag in mode lines.
+This display updates automatically every minute.
 If `display-time-day-and-date' is non-nil, the current day and date
 are displayed as well.
-After each update, `display-time-hook' is run with `run-hooks'."
+This runs the normal hook `display-time-hook' after each update."
   (interactive)
-  (let ((live (and display-time-process
-		   (eq (process-status display-time-process) 'run))))
-    (if (not live)
-	(progn
-	  (if display-time-process
-	      (delete-process display-time-process))
-	  (or global-mode-string (setq global-mode-string '("")))
-	  (or (memq 'display-time-string global-mode-string)
-	      (setq global-mode-string
-		    (append global-mode-string '(display-time-string))))
-	  (setq display-time-string "")
-	  ;; Using a pty is wasteful, and the separate session causes
-	  ;; annoyance sometimes (some systems kill idle sessions).
-	  (let ((process-connection-type nil))
-	    (setq display-time-process
-		  (start-process "display-time" nil
-				 (expand-file-name "wakeup" exec-directory)
-				 (int-to-string display-time-interval))))
-	  (process-kill-without-query display-time-process)
-	  (set-process-sentinel display-time-process 'display-time-sentinel)
-	  (set-process-filter display-time-process 'display-time-filter)))))
-
-(defun display-time-sentinel (proc reason)
-  (or (eq (process-status proc) 'run)
-      (setq display-time-string ""))
-  ;; Force mode-line updates
-  (save-excursion (set-buffer (other-buffer)))
-  (set-buffer-modified-p (buffer-modified-p))
-  (sit-for 0))
+  (display-time-mode 1))
+
+;; This business used to be simpler when all mode lines had the same
+;; face and the image could just be pbm.  Now we try to rely on an xpm
+;; image with a transparent background.  Otherwise, set the background
+;; for pbm.
+
+(defcustom display-time-mail-face nil
+  "Face to use for `display-time-mail-string'.
+If `display-time-use-mail-icon' is non-nil, the image's
+background color is the background of this face.  Set this to
+make the mail indicator stand out on a color display."
+  :group 'mode-line-faces
+  :group 'display-time
+  :version "22.1"
+  :type '(choice (const :tag "None" nil) face))
+
+(defvar display-time-mail-icon
+  (find-image '((:type xpm :file "letter.xpm" :ascent center)
+		(:type pbm :file "letter.pbm" :ascent center)))
+  "Image specification to offer as the mail indicator on a graphic display.
+See `display-time-use-mail-icon' and `display-time-mail-face'.")
 
-(defvar display-time-string-forms
-  '((if display-time-day-and-date
-        (format "%s %s %s " dayname monthname day)
+;; Fixme: Default to icon on graphical display?
+(defcustom display-time-use-mail-icon nil
+  "Non-nil means use an icon as mail indicator on a graphic display.
+Otherwise use `display-time-mail-string'.  The icon may consume less
+of the mode line.  It is specified by `display-time-mail-icon'."
+  :group 'display-time
+  :type 'boolean)
+
+;; Fixme: maybe default to the character if we can display Unicode.
+(defcustom display-time-mail-string "Mail"
+  "String to use as the mail indicator in `display-time-string-forms'.
+This can use the Unicode letter character if you can display it."
+  :group 'display-time
+  :version "22.1"
+  :type '(choice (const "Mail")
+		 ;; Use :tag here because the Lucid menu won't display
+		 ;; multibyte text.
+		 (const :tag "Unicode letter character" "✉")
+		 string))
+
+(defcustom display-time-format nil
+  "*String specifying format for displaying the time in the mode line.
+See the function `format-time-string' for an explanation of
+how to write this string.  If this is nil, the defaults
+depend on `display-time-day-and-date' and `display-time-24hr-format'."
+  :type '(choice (const :tag "Default" nil)
+		 string)
+  :group 'display-time)
+
+(defcustom display-time-string-forms
+  '((if (and (not display-time-format) display-time-day-and-date)
+	(format-time-string "%a %b %e " now)
       "")
-    (format "%s:%s%s"
-            (if display-time-24hr-format 24-hours 12-hours)
-            minutes
-            (if display-time-24hr-format "" am-pm))
+    (propertize
+     (format-time-string (or display-time-format
+			     (if display-time-24hr-format "%H:%M" "%-I:%M%p"))
+			 now)
+     'help-echo (format-time-string "%a %b %e, %Y" now))
     load
-    (if mail " Mail" ""))
-  "*A list of expressions governing display of the time in the mode line.
+    (if mail
+	;; Build the string every time to act on customization.
+	;; :set-after doesn't help for `customize-option'.  I think it
+	;; should.
+	(concat
+	 " "
+	 (propertize
+	  display-time-mail-string
+	  'display `(when (and display-time-use-mail-icon
+			       (display-graphic-p))
+		      ,@display-time-mail-icon
+		      ,@(if (and display-time-mail-face
+				 (memq (plist-get (cdr display-time-mail-icon)
+						  :type)
+				       '(pbm xbm)))
+			    (let ((bg (face-attribute display-time-mail-face
+						      :background)))
+			      (if (stringp bg)
+				  (list :background bg)))))
+	  'face display-time-mail-face
+	  'help-echo "You have new mail; mouse-2: Read mail"
+	  'mouse-face 'mode-line-highlight
+	  'local-map (make-mode-line-mouse-map 'mouse-2
+					       read-mail-command)))
+      ""))
+  "*List of expressions governing display of the time in the mode line.
+For most purposes, you can control the time format using `display-time-format'
+which is a more standard interface.
+
 This expression is a list of expressions that can involve the keywords
 `load', `day', `month', and `year', `12-hours', `24-hours', `minutes',
 `seconds', all numbers in string form, and `monthname', `dayname', `am-pm',
@@ -111,46 +216,129 @@ and `time-zone' all alphabetic strings, and `mail' a true/nil value.
 For example, the form
 
   '((substring year -2) \"/\" month \"/\" day
-    " " 24-hours \":\" minutes \":\" seconds
+    \" \" 24-hours \":\" minutes \":\" seconds
     (if time-zone \" (\") time-zone (if time-zone \")\")
     (if mail \" Mail\" \"\"))
 
-would give mode line times like `94/12/30 21:07:48 (UTC)'.")
+would give mode line times like `94/12/30 21:07:48 (UTC)'."
+  :type 'sexp
+  :group 'display-time)
 
-(defun display-time-filter (proc string)
-  (let* ((time (current-time-string))
-         (load (condition-case ()
-                   (if (zerop (car (load-average))) ""
-                     (let ((str (format " %03d" (car (load-average)))))
-                       (concat (substring str 0 -2) "." (substring str -2))))
-                 (error "")))
+(defun display-time-event-handler ()
+  (display-time-update)
+  ;; Do redisplay right now, if no input pending.
+  (sit-for 0)
+  (let* ((current (current-time))
+	 (timer display-time-timer)
+	 ;; Compute the time when this timer will run again, next.
+	 (next-time (timer-relative-time
+		     (list (aref timer 1) (aref timer 2) (aref timer 3))
+		     (* 5 (aref timer 4)) 0)))
+    ;; If the activation time is far in the past,
+    ;; skip executions until we reach a time in the future.
+    ;; This avoids a long pause if Emacs has been suspended for hours.
+    (or (> (nth 0 next-time) (nth 0 current))
+	(and (= (nth 0 next-time) (nth 0 current))
+	     (> (nth 1 next-time) (nth 1 current)))
+	(and (= (nth 0 next-time) (nth 0 current))
+	     (= (nth 1 next-time) (nth 1 current))
+	     (> (nth 2 next-time) (nth 2 current)))
+	(progn
+	  (timer-set-time timer (timer-next-integral-multiple-of-time
+				 current display-time-interval)
+			  display-time-interval)
+	  (timer-activate timer)))))
+
+(defun display-time-next-load-average ()
+  (interactive)
+  (if (= 3 (setq display-time-load-average (1+ display-time-load-average)))
+      (setq display-time-load-average 0))
+  (display-time-update)
+  (sit-for 0))
+
+(defun display-time-mail-check-directory ()
+  (let ((mail-files (directory-files display-time-mail-directory t))
+	(size 0))
+    (while (and mail-files (= size 0))
+      ;; Count size of regular files only.
+      (setq size (+ size (or (and (file-regular-p (car mail-files))
+				  (nth 7 (file-attributes (car mail-files))))
+			     0)))
+      (setq mail-files (cdr mail-files)))
+    (if (> size 0)
+	size
+      nil)))
+
+(defun display-time-update ()
+  "Update the display-time info for the mode line.
+However, don't redisplay right now.
+
+This is used for things like Rmail `g' that want to force an
+update which can wait for the next redisplay."
+  (let* ((now (current-time))
+	 (time (current-time-string now))
+         (load (if (null display-time-load-average)
+		   ""
+		 (condition-case ()
+		     ;; Do not show values less than
+		     ;; `display-time-load-average-threshold'.
+		     (if (> (* display-time-load-average-threshold 100)
+			    (nth display-time-load-average (load-average)))
+			 ""
+		       ;; The load average number is mysterious, so
+		       ;; provide some help.
+		       (let ((str (format " %03d"
+					  (nth display-time-load-average
+					       (load-average)))))
+			 (propertize
+			  (concat (substring str 0 -2) "." (substring str -2))
+			  'local-map (make-mode-line-mouse-map
+				      'mouse-2 'display-time-next-load-average)
+			  'mouse-face 'mode-line-highlight
+			  'help-echo (concat
+				      "System load average for past "
+				      (if (= 0 display-time-load-average)
+					  "1 minute"
+					(if (= 1 display-time-load-average)
+					    "5 minutes"
+					  "15 minutes"))
+				      "; mouse-2: next"))))
+		   (error ""))))
          (mail-spool-file (or display-time-mail-file
                               (getenv "MAIL")
                               (concat rmail-spool-directory
                                       (user-login-name))))
-	 (mail (and (stringp mail-spool-file)
-		    (or (null display-time-server-down-time)
-			;; If have been down for 20 min, try again.
-			(> (- (nth 1 (current-time))
-			      display-time-server-down-time)
-			   1200))
-		    (let ((start-time (current-time)))
-		      (prog1
-			  (display-time-file-nonempty-p mail-spool-file)
-			(if (> (- (nth 1 (current-time)) (nth 1 start-time))
-			       20)
-			    ;; Record that mail file is not accessible.
-			    (setq display-time-server-down-time 
-				  (nth 1 (current-time)))
-			  ;; Record that mail file is accessible.
-			  (setq display-time-server-down-time nil))))))
+	 (mail (or (and display-time-mail-function
+			(funcall display-time-mail-function))
+		   (and display-time-mail-directory
+			(display-time-mail-check-directory))
+		   (and (stringp mail-spool-file)
+			(or (null display-time-server-down-time)
+			    ;; If have been down for 20 min, try again.
+			    (> (- (nth 1 now) display-time-server-down-time)
+			       1200)
+			    (and (< (nth 1 now) display-time-server-down-time)
+				 (> (- (nth 1 now)
+				       display-time-server-down-time)
+				    -64336)))
+			(let ((start-time (current-time)))
+			  (prog1
+			      (display-time-file-nonempty-p mail-spool-file)
+			    (if (> (- (nth 1 (current-time))
+				      (nth 1 start-time))
+				   20)
+				;; Record that mail file is not accessible.
+				(setq display-time-server-down-time
+				      (nth 1 (current-time)))
+			      ;; Record that mail file is accessible.
+			      (setq display-time-server-down-time nil)))))))
          (24-hours (substring time 11 13))
-         (hour (string-to-int 24-hours))
+         (hour (string-to-number 24-hours))
          (12-hours (int-to-string (1+ (% (+ hour 11) 12))))
          (am-pm (if (>= hour 12) "pm" "am"))
          (minutes (substring time 14 16))
          (seconds (substring time 17 19))
-         (time-zone (car (cdr (current-time-zone))))
+         (time-zone (car (cdr (current-time-zone now))))
          (day (substring time 8 10))
          (year (substring time 20 24))
          (monthname (substring time 4 7))
@@ -163,16 +351,49 @@ would give mode line times like `94/12/30 21:07:48 (UTC)'.")
               ("Sep" . "9") ("Oct" . "10") ("Nov" . "11") ("Dec" . "12")))))
          (dayname (substring time 0 3)))
     (setq display-time-string
-          (mapconcat 'eval display-time-string-forms "")))
-  (run-hooks 'display-time-hook)
-  ;; Force redisplay of all buffers' mode lines to be considered.
-  (save-excursion (set-buffer (other-buffer)))
-  (set-buffer-modified-p (buffer-modified-p))
-  ;; Do redisplay right now, if no input pending.
-  (sit-for 0))
+          (mapconcat 'eval display-time-string-forms ""))
+    ;; This is inside the let binding, but we are not going to document
+    ;; what variables are available.
+    (run-hooks 'display-time-hook))
+  (force-mode-line-update))
 
 (defun display-time-file-nonempty-p (file)
   (and (file-exists-p file)
        (< 0 (nth 7 (file-attributes (file-chase-links file))))))
 
+;;;###autoload
+(define-minor-mode display-time-mode
+  "Toggle display of time, load level, and mail flag in mode lines.
+With a numeric arg, enable this display if arg is positive.
+
+When this display is enabled, it updates automatically every minute.
+If `display-time-day-and-date' is non-nil, the current day and date
+are displayed as well.
+This runs the normal hook `display-time-hook' after each update."
+  :global t :group 'display-time
+  (and display-time-timer (cancel-timer display-time-timer))
+  (setq display-time-timer nil)
+  (setq display-time-string "")
+  (or global-mode-string (setq global-mode-string '("")))
+  (setq display-time-load-average display-time-default-load-average)
+  (if display-time-mode
+      (progn
+	(or (memq 'display-time-string global-mode-string)
+	    (setq global-mode-string
+		  (append global-mode-string '(display-time-string))))
+	;; Set up the time timer.
+	(setq display-time-timer
+	      (run-at-time t display-time-interval
+			   'display-time-event-handler))
+	;; Make the time appear right away.
+	(display-time-update)
+	;; When you get new mail, clear "Mail" from the mode line.
+	(add-hook 'rmail-after-get-new-mail-hook
+		  'display-time-event-handler))
+    (remove-hook 'rmail-after-get-new-mail-hook
+		 'display-time-event-handler)))
+
+(provide 'time)
+
+;;; arch-tag: b9c1623f-b5cb-48e4-b650-482a4d23c5a6
 ;;; time.el ends here