517 lines
18 KiB
EmacsLisp
517 lines
18 KiB
EmacsLisp
;;; timezone.el --- time zone package for GNU Emacs
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;; Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
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;; Author: Masanobu Umeda
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;; Maintainer: umerin@mse.kyutech.ac.jp
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;; Keywords: news
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;; This file is free software; you can redistribute it and/or modify
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;; it under the terms of the GNU General Public License as published by
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;; the Free Software Foundation; either version 2, or (at your option)
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;; any later version.
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;; This file is distributed in the hope that it will be useful,
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;; but WITHOUT ANY WARRANTY; without even the implied warranty of
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;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;; GNU General Public License for more details.
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;; You should have received a copy of the GNU General Public License
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;; along with GNU Emacs; see the file COPYING. If not, write to
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;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
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;;; Commentary:
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;; Modified 1 February 1994 by Kyle Jones to fix broken
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;; timezone-floor function.
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;; Modified 25 January 1994 by Kyle Jones so that it will
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;; work under version 18 of Emacs. Provided timezone-floor
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;; and timezone-abs functions.
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;; Modified 4 October 1999 by Yuuichi Teranishi so that it will
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;; work with old GNUS 3.14.4 under version 18 of Emacs.
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;;; Code:
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(defvar timezone-world-timezones
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'(("PST" . -800)
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("PDT" . -700)
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("MST" . -700)
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("MDT" . -600)
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("CST" . -600)
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("CDT" . -500)
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("EST" . -500)
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("EDT" . -400)
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("AST" . -400) ;by <clamen@CS.CMU.EDU>
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("NST" . -330) ;by <clamen@CS.CMU.EDU>
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("UT" . +000)
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("GMT" . +000)
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("BST" . +100)
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("MET" . +100)
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("EET" . +200)
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("JST" . +900)
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("GMT+1" . +100) ("GMT+2" . +200) ("GMT+3" . +300)
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("GMT+4" . +400) ("GMT+5" . +500) ("GMT+6" . +600)
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("GMT+7" . +700) ("GMT+8" . +800) ("GMT+9" . +900)
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("GMT+10" . +1000) ("GMT+11" . +1100) ("GMT+12" . +1200) ("GMT+13" . +1300)
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("GMT-1" . -100) ("GMT-2" . -200) ("GMT-3" . -300)
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("GMT-4" . -400) ("GMT-5" . -500) ("GMT-6" . -600)
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("GMT-7" . -700) ("GMT-8" . -800) ("GMT-9" . -900)
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("GMT-10" . -1000) ("GMT-11" . -1100) ("GMT-12" . -1200))
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"*Time differentials of timezone from GMT in +-HHMM form.
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This list is obsolescent, and is present only for backwards compatibility,
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because time zone names are ambiguous in practice.
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Use `current-time-zone' instead.")
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(defvar timezone-months-assoc
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'(("JAN" . 1)("FEB" . 2)("MAR" . 3)
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("APR" . 4)("MAY" . 5)("JUN" . 6)
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("JUL" . 7)("AUG" . 8)("SEP" . 9)
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("OCT" . 10)("NOV" . 11)("DEC" . 12))
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"Alist of first three letters of a month and its numerical representation.")
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(defun timezone-make-date-arpa-standard (date &optional local timezone)
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"Convert DATE to an arpanet standard date.
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Optional 2nd argument LOCAL specifies the default local timezone of the DATE;
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if nil, GMT is assumed.
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Optional 3rd argument TIMEZONE specifies a time zone to be represented in;
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if nil, the local time zone is assumed."
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(let ((new (timezone-fix-time date local timezone)))
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(timezone-make-arpa-date (aref new 0) (aref new 1) (aref new 2)
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(timezone-make-time-string
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(aref new 3) (aref new 4) (aref new 5))
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(aref new 6))
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))
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(defun timezone-make-date-sortable (date &optional local timezone)
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"Convert DATE to a sortable date string.
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Optional 2nd argument LOCAL specifies the default local timezone of the DATE;
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if nil, GMT is assumed.
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Optional 3rd argument TIMEZONE specifies a timezone to be represented in;
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if nil, the local time zone is assumed."
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(let ((new (timezone-fix-time date local timezone)))
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(timezone-make-sortable-date (aref new 0) (aref new 1) (aref new 2)
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(timezone-make-time-string
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(aref new 3) (aref new 4) (aref new 5)))
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))
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;;
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;; Parsers and Constructors of Date and Time
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;;
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(defun timezone-make-arpa-date (year month day time &optional timezone)
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"Make arpanet standard date string from YEAR, MONTH, DAY, and TIME.
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Optional argument TIMEZONE specifies a time zone."
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(let ((zone
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(if (listp timezone)
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(let* ((m (timezone-zone-to-minute timezone))
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(absm (if (< m 0) (- m) m)))
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(format "%c%02d%02d"
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(if (< m 0) ?- ?+) (/ absm 60) (% absm 60)))
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timezone)))
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(format "%02d %s %04d %s %s"
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day
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(capitalize (car (rassq month timezone-months-assoc)))
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year
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time
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zone)))
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(defun timezone-make-sortable-date (year month day time)
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"Make sortable date string from YEAR, MONTH, DAY, and TIME."
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(format "%4d%02d%02d%s"
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year month day time))
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(defun timezone-make-time-string (hour minute second)
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"Make time string from HOUR, MINUTE, and SECOND."
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(format "%02d:%02d:%02d" hour minute second))
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(defun timezone-parse-date (date)
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"Parse DATE and return a vector [YEAR MONTH DAY TIME TIMEZONE].
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19 is prepended to year if necessary. Timezone may be nil if nothing.
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Understands the following styles:
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(1) 14 Apr 89 03:20[:12] [GMT]
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(2) Fri, 17 Mar 89 4:01[:33] [GMT]
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(3) Mon Jan 16 16:12[:37] [GMT] 1989
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(4) 6 May 1992 1641-JST (Wednesday)
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(5) 22-AUG-1993 10:59:12.82
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(6) Thu, 11 Apr 16:17:12 91 [MET]
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(7) Mon, 6 Jul 16:47:20 T 1992 [MET]
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(8) 1996-06-24 21:13:12 [GMT]
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(9) 1996-06-24 21:13-ZONE"
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;; Get rid of any text properties.
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(and (stringp date)
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(or (text-properties-at 0 date)
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(next-property-change 0 date))
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(setq date (copy-sequence date))
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(set-text-properties 0 (length date) nil date))
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(let ((date (or date ""))
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(year nil)
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(month nil)
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(day nil)
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(time nil)
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(zone nil)) ;This may be nil.
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(cond ((string-match
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"\\([0-9]+\\)[ \t]+\\([^ \t,]+\\)[ \t]+\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9:]+\\)[ \t]*\\([-+a-zA-Z0-9]+\\)" date)
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;; Styles: (1) and (2) with timezone and buggy timezone
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;; This is most common in mail and news,
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;; so it is worth trying first.
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(setq year 3 month 2 day 1 time 4 zone 5))
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((string-match
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"\\([0-9]+\\)[ \t]+\\([^ \t,]+\\)[ \t]+\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9:]+\\)[ \t]*\\'" date)
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;; Styles: (1) and (2) without timezone
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(setq year 3 month 2 day 1 time 4 zone nil))
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((string-match
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"\\([^ \t,]+\\),[ \t]+\\([0-9]+\\)[ \t]+\\([^ \t,]+\\)[ \t]+\\([0-9]+:[0-9:]+\\)[ \t]+\\(T[ \t]+\\|\\)\\([0-9]+\\)[ \t]*\\'" date)
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;; Styles: (6) and (7) without timezone
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(setq year 6 month 3 day 2 time 4 zone nil))
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((string-match
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"\\([^ \t,]+\\),[ \t]+\\([0-9]+\\)[ \t]+\\([^ \t,]+\\)[ \t]+\\([0-9]+:[0-9:]+\\)[ \t]+\\(T[ \t]+\\|\\)\\([0-9]+\\)[ \t]*\\([-+a-zA-Z0-9]+\\)" date)
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;; Styles: (6) and (7) with timezone and buggy timezone
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(setq year 6 month 3 day 2 time 4 zone 7))
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((string-match
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"\\([^ \t,]+\\)[ \t]+\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9:]+\\)[ \t]+\\([0-9]+\\)" date)
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;; Styles: (3) without timezone
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(setq year 4 month 1 day 2 time 3 zone nil))
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((string-match
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"\\([^ \t,]+\\)[ \t]+\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9:]+\\)[ \t]+\\([-+a-zA-Z0-9]+\\)[ \t]+\\([0-9]+\\)" date)
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;; Styles: (3) with timezone
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(setq year 5 month 1 day 2 time 3 zone 4))
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((string-match
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"\\([0-9]+\\)[ \t]+\\([^ \t,]+\\)[ \t]+\\([0-9]+\\)[ \t]+\\([0-9]+\\)[ \t]*\\([-+a-zA-Z0-9]+\\)" date)
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;; Styles: (4) with timezone
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(setq year 3 month 2 day 1 time 4 zone 5))
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((string-match
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"\\([0-9]+\\)-\\([A-Za-z]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+:[0-9]+\\)\\(\\.[0-9]+\\)?[ \t]+\\([-+a-zA-Z0-9]+\\)" date)
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;; Styles: (5) with timezone.
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(setq year 3 month 2 day 1 time 4 zone 6))
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((string-match
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"\\([0-9]+\\)-\\([A-Za-z]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+:[0-9]+\\)\\(\\.[0-9]+\\)?" date)
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;; Styles: (5) without timezone.
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(setq year 3 month 2 day 1 time 4 zone nil))
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((string-match
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"\\([0-9]+\\)-\\([0-9]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+:[0-9]+\\)[ \t]*\\([-+a-zA-Z0-9]+\\)" date)
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;; Styles: (8) with timezone.
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(setq year 1 month 2 day 3 time 4 zone 5))
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((string-match
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"\\([0-9]+\\)-\\([0-9]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+\\)[ \t]*\\([-+a-zA-Z0-9:]+\\)" date)
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;; Styles: (8) with timezone with a colon in it.
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(setq year 1 month 2 day 3 time 4 zone 5))
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((string-match
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"\\([0-9]+\\)-\\([0-9]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+:[0-9]+\\)" date)
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;; Styles: (8) without timezone.
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(setq year 1 month 2 day 3 time 4 zone nil))
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)
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(when year
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(setq year (match-string year date))
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;; Guess ambiguous years. Assume years < 69 don't predate the
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;; Unix Epoch, so are 2000+. Three-digit years are assumed to
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;; be relative to 1900.
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(if (< (length year) 4)
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(let ((y (string-to-int year)))
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(if (< y 69)
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(setq y (+ y 100)))
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(setq year (int-to-string (+ 1900 y)))))
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(setq month
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(if (= (aref date (+ (match-beginning month) 2)) ?-)
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;; Handle numeric months, spanning exactly two digits.
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(substring date
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(match-beginning month)
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(+ (match-beginning month) 2))
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(let* ((string (substring date
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(match-beginning month)
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(+ (match-beginning month) 3)))
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(monthnum
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(cdr (assoc (upcase string) timezone-months-assoc))))
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(if monthnum
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(int-to-string monthnum)))))
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(setq day (match-string day date))
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(setq time (match-string time date)))
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(if zone (setq zone (match-string zone date)))
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;; Return a vector.
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(if (and year month)
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(vector year month day time zone)
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(vector "0" "0" "0" "0" nil))))
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(defun timezone-parse-time (time)
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"Parse TIME (HH:MM:SS) and return a vector [hour minute second].
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Recognize HH:MM:SS, HH:MM, HHMMSS, HHMM."
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(let ((time (or time ""))
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(hour nil)
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(minute nil)
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(second nil))
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(cond ((string-match "\\`\\([0-9]+\\):\\([0-9]+\\):\\([0-9]+\\)\\'" time)
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;; HH:MM:SS
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(setq hour 1 minute 2 second 3))
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((string-match "\\`\\([0-9]+\\):\\([0-9]+\\)\\'" time)
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;; HH:MM
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(setq hour 1 minute 2 second nil))
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((string-match "\\`\\([0-9][0-9]\\)\\([0-9][0-9]\\)\\([0-9][0-9]\\)\\'" time)
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;; HHMMSS
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(setq hour 1 minute 2 second 3))
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((string-match "\\`\\([0-9][0-9]\\)\\([0-9][0-9]\\)\\'" time)
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;; HHMM
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(setq hour 1 minute 2 second nil))
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)
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;; Return [hour minute second]
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(vector
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(if hour
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(substring time (match-beginning hour) (match-end hour)) "0")
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(if minute
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(substring time (match-beginning minute) (match-end minute)) "0")
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(if second
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(substring time (match-beginning second) (match-end second)) "0"))
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))
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;; Miscellaneous
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(defun timezone-zone-to-minute (timezone)
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"Translate TIMEZONE to an integer minute offset from GMT.
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TIMEZONE can be a cons cell containing the output of `current-time-zone',
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or an integer of the form +-HHMM, or a time zone name."
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(cond
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((consp timezone)
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(/ (car timezone) 60))
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(timezone
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(progn
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(setq timezone
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(or (and (stringp timezone) (cdr (assoc (upcase timezone) timezone-world-timezones)))
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;; +900
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timezone))
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(if (stringp timezone)
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(setq timezone (string-to-int timezone)))
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;; Taking account of minute in timezone.
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;; HHMM -> MM
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(let* ((abszone (abs timezone))
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(minutes (+ (* 60 (/ abszone 100)) (% abszone 100))))
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(if (< timezone 0) (- minutes) minutes))))
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(t 0)))
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(defun timezone-floor (arg &optional divisor)
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"Return the largest integer no grater than ARG.
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With optional DIVISOR, return the largest integer no greater than ARG/DIVISOR."
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(if (null divisor)
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(setq divisor 1))
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(if (< arg 0)
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(- (/ (- divisor 1 arg) divisor))
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(/ arg divisor)))
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(defun timezone-time-from-absolute (date seconds)
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"Compute the UTC time equivalent to DATE at time SECONDS after midnight.
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Return a list suitable as an argument to `current-time-zone',
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or nil if the date cannot be thus represented.
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DATE is the number of days elapsed since the (imaginary)
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Gregorian date Sunday, December 31, 1 BC."
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(let* ((current-time-origin 719163)
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;; (timezone-absolute-from-gregorian 1 1 1970)
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(days (- date current-time-origin))
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(days-1 (/ days 65536))
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(days-2 (% (/ days 256) 256))
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(days-3 (% days 256))
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;; (seconds-per-day (float 86400))
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(seconds-per-day-1 1)
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(seconds-per-day-2 81)
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(seconds-per-day-3 128)
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;; (seconds (+ seconds (* days seconds-per-day)))
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;; (current-time-arithmetic-base (float 65536))
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;; (hi (timezone-floor (/ seconds current-time-arithmetic-base)))
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;; (hibase (* hi current-time-arithmetic-base))
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;; (lo (timezone-floor (- seconds hibase)))
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(seconds-1 (/ seconds 65536))
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(seconds-2 (% (/ seconds 256) 256))
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(seconds-3 (% seconds 256))
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hi lo
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r
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seconds-per-day*days-1
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seconds-per-day*days-2
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seconds-per-day*days-3)
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(setq r (* days-3 seconds-per-day-3)
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seconds-per-day*days-3 (% r 256))
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(setq r (+ (/ r 256)
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(* days-2 seconds-per-day-3)
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(* days-3 seconds-per-day-2))
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seconds-per-day*days-2 (% r 256))
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(setq seconds-per-day*days-1 (+ (/ r 256)
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(* days-1 seconds-per-day-3)
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(* (/ days 256) seconds-per-day-2)
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(* days seconds-per-day-1)))
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(setq r (+ seconds-2 seconds-per-day*days-2)
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seconds-2 (% r 256)
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seconds-1 (+ seconds-1 (/ r 256)))
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(setq lo (+ (* seconds-2 256)
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seconds-3 seconds-per-day*days-3))
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(setq hi (+ seconds-1 seconds-per-day*days-1))
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;; (and (< (abs (- seconds (+ hibase lo))) 2) ; Check for integer overflow.
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;; (cons hi lo))
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(cons hi lo)
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))
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(defun timezone-time-zone-from-absolute (date seconds)
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"Compute the local time zone for DATE at time SECONDS after midnight.
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Return a list in the same format as current-time-zone's result,
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or nil if the local time zone could not be computed.
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DATE is the number of days elapsed since the (imaginary)
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Gregorian date Sunday, December 31, 1 BC."
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(and (fboundp 'current-time-zone)
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(let ((utc-time (timezone-time-from-absolute date seconds)))
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(and utc-time
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(let ((zone (current-time-zone utc-time)))
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(and (car zone) zone))))))
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(defsubst timezone-fix-time-1 (year month day hour minute second)
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"Fix date and time.
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For old `timezone-fix-time' function.
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Arguments are YEAR, MONTH, DAY, HOUR, MINUTE and SECOND."
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;; MINUTE may be larger than 60 or smaller than -60.
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(let ((hour-fix
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(if (< minute 0)
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;;(/ (- minute 59) 60) (/ minute 60)
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;; ANSI C compliance about truncation of integer division
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;; by eggert@twinsun.com (Paul Eggert)
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(- (/ (- 59 minute) 60)) (/ minute 60))))
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(setq hour (+ hour hour-fix))
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(setq minute (- minute (* 60 hour-fix))))
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;; HOUR may be larger than 24 or smaller than 0.
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(cond ((<= 24 hour) ;24 -> 00
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(setq hour (- hour 24))
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(setq day (1+ day))
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(if (< (timezone-last-day-of-month month year) day)
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(progn
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(setq month (1+ month))
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(setq day 1)
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(if (< 12 month)
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(progn
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(setq month 1)
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(setq year (1+ year))
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))
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)))
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((> 0 hour)
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(setq hour (+ hour 24))
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(setq day (1- day))
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(if (> 1 day)
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(progn
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(setq month (1- month))
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(if (> 1 month)
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(progn
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(setq month 12)
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(setq year (1- year))
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))
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(setq day (timezone-last-day-of-month month year))
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)))
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)
|
||
(vector year month day hour minute second))
|
||
|
||
(defsubst timezone-fix-time-2 (date local timezone)
|
||
"Convert DATE (default timezone LOCAL) to YYYY-MM-DD-HH-MM-SS-ZONE vector.
|
||
If LOCAL is nil, it is assumed to be GMT.
|
||
If TIMEZONE is nil, use the local time zone."
|
||
(let* ((date (timezone-parse-date date))
|
||
(year (string-to-int (aref date 0)))
|
||
(year (cond ((< year 50)
|
||
(+ year 2000))
|
||
((< year 100)
|
||
(+ year 1900))
|
||
(t year)))
|
||
(month (string-to-int (aref date 1)))
|
||
(day (string-to-int (aref date 2)))
|
||
(time (timezone-parse-time (aref date 3)))
|
||
(hour (string-to-int (aref time 0)))
|
||
(minute (string-to-int (aref time 1)))
|
||
(second (string-to-int (aref time 2)))
|
||
(local (or (aref date 4) local)) ;Use original if defined
|
||
(timezone
|
||
(or timezone
|
||
(timezone-time-zone-from-absolute
|
||
(timezone-absolute-from-gregorian month day year)
|
||
(+ second (* 60 (+ minute (* 60 hour)))))))
|
||
(diff (- (timezone-zone-to-minute timezone)
|
||
(timezone-zone-to-minute local)))
|
||
(minute (+ minute diff))
|
||
(hour-fix (timezone-floor minute 60)))
|
||
(setq hour (+ hour hour-fix))
|
||
(setq minute (- minute (* 60 hour-fix)))
|
||
;; HOUR may be larger than 24 or smaller than 0.
|
||
(cond ((<= 24 hour) ;24 -> 00
|
||
(setq hour (- hour 24))
|
||
(setq day (1+ day))
|
||
(if (< (timezone-last-day-of-month month year) day)
|
||
(progn
|
||
(setq month (1+ month))
|
||
(setq day 1)
|
||
(if (< 12 month)
|
||
(progn
|
||
(setq month 1)
|
||
(setq year (1+ year))
|
||
))
|
||
)))
|
||
((> 0 hour)
|
||
(setq hour (+ hour 24))
|
||
(setq day (1- day))
|
||
(if (> 1 day)
|
||
(progn
|
||
(setq month (1- month))
|
||
(if (> 1 month)
|
||
(progn
|
||
(setq month 12)
|
||
(setq year (1- year))
|
||
))
|
||
(setq day (timezone-last-day-of-month month year))
|
||
)))
|
||
)
|
||
(vector year month day hour minute second timezone)))
|
||
|
||
(defun timezone-fix-time (a1 a2 a3 &optional a4 a5 a6)
|
||
"Fix date and time.
|
||
(Old API: A1=YEAR A2=MONTH A3=DAY A4=HOUR A5=MINUTE A6=SECOND).
|
||
Convert DATE (default timezone LOCAL) to YYYY-MM-DD-HH-MM-SS-ZONE vector.
|
||
If LOCAL is nil, it is assumed to be GMT.
|
||
If TIMEZONE is nil, use the local time zone.
|
||
(New API: A1=DATE A2=LOCAL A3=TIMEZONE)"
|
||
(if a4
|
||
(timezone-fix-time-1 a1 a2 a3 a4 a5 a6)
|
||
(timezone-fix-time-2 a1 a2 a3)))
|
||
|
||
;; Partly copied from Calendar program by Edward M. Reingold.
|
||
;; Thanks a lot.
|
||
|
||
(defun timezone-last-day-of-month (month year)
|
||
"The last day in MONTH during YEAR."
|
||
(if (and (= month 2) (timezone-leap-year-p year))
|
||
29
|
||
(aref [31 28 31 30 31 30 31 31 30 31 30 31] (1- month))))
|
||
|
||
(defun timezone-leap-year-p (year)
|
||
"Return t if YEAR is a Gregorian leap year."
|
||
(or (and (zerop (% year 4))
|
||
(not (zerop (% year 100))))
|
||
(zerop (% year 400))))
|
||
|
||
(defun timezone-day-number (month day year)
|
||
"Return the day number within the year of the date MONTH/DAY/YEAR."
|
||
(let ((day-of-year (+ day (* 31 (1- month)))))
|
||
(if (> month 2)
|
||
(progn
|
||
(setq day-of-year (- day-of-year (/ (+ 23 (* 4 month)) 10)))
|
||
(if (timezone-leap-year-p year)
|
||
(setq day-of-year (1+ day-of-year)))))
|
||
day-of-year))
|
||
|
||
(defun timezone-absolute-from-gregorian (month day year)
|
||
"The number of days between the Gregorian date 12/31/1 BC and MONTH/DAY/YEAR.
|
||
The Gregorian date Sunday, December 31, 1 BC is imaginary."
|
||
(+ (timezone-day-number month day year);; Days this year
|
||
(* 365 (1- year));; + Days in prior years
|
||
(/ (1- year) 4);; + Julian leap years
|
||
(- (/ (1- year) 100));; - century years
|
||
(/ (1- year) 400)));; + Gregorian leap years
|
||
|
||
;;; @ End.
|
||
;;;
|
||
|
||
(require 'product)
|
||
(product-provide (provide 'timezone) (require 'apel-ver))
|
||
|
||
;;; timezone.el ends here
|