1 ;;; parse-time.el --- parsing time strings
3 ;; Copyright (C) 1996, 2000-2014 Free Software Foundation, Inc.
5 ;; Author: Erik Naggum <erik@naggum.no>
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software: you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation, either version 3 of the License, or
13 ;; (at your option) any later version.
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
25 ;; With the introduction of the `encode-time', `decode-time', and
26 ;; `format-time-string' functions, dealing with time became simpler in
27 ;; Emacs. However, parsing time strings is still largely a matter of
28 ;; heuristics and no common interface has been designed.
30 ;; `parse-time-string' parses a time in a string and returns a list of 9
31 ;; values, just like `decode-time', where unspecified elements in the
32 ;; string are returned as nil. `encode-time' may be applied on these
33 ;; values to obtain an internal time value.
37 (eval-when-compile (require 'cl-lib))
39 (defvar parse-time-digits (make-vector 256 nil))
41 ;; Byte-compiler warnings
42 (defvar parse-time-elt)
43 (defvar parse-time-val)
45 (unless (aref parse-time-digits ?0)
46 (cl-loop for i from ?0 to ?9
47 do (aset parse-time-digits i (- i ?0))))
49 (defsubst digit-char-p (char)
50 (aref parse-time-digits char))
52 (defsubst parse-time-string-chars (char)
54 (let (case-fold-search str)
55 (cond ((eq char ?+) 1)
58 ((string-match "[[:upper:]]" (setq str (string char))) ?A)
59 ((string-match "[[:lower:]]" str) ?a)
60 ((string-match "[[:digit:]]" str) ?0)))))
62 (put 'parse-error 'error-conditions '(parse-error error))
63 (put 'parse-error 'error-message "Parsing error")
65 (defsubst parse-integer (string &optional start end)
66 "[CL] Parse and return the integer in STRING, or nil if none."
70 (end (or end (length string))))
72 (let ((sign (aref string index)))
73 (if (or (eq sign ?+) (eq sign ?-))
74 (setq sign (parse-time-string-chars sign)
77 (while (and (< index end)
78 (setq digit (digit-char-p (aref string index))))
79 (setq integer (+ (* integer 10) digit)
82 (signal 'parse-error `("not an integer"
83 ,(substring string (or start 0) end)))
86 (defun parse-time-tokenize (string)
87 "Tokenize STRING into substrings."
95 (while (and (< index end) ;Skip invalid characters.
96 (not (setq c (parse-time-string-chars (aref string index)))))
98 (setq start index all-digits (eq c ?0))
99 (while (and (< (cl-incf index) end) ;Scan valid characters.
100 (setq c (parse-time-string-chars (aref string index))))
101 (setq all-digits (and all-digits (eq c ?0))))
103 (push (if all-digits (parse-integer string start index)
104 (substring string start index))
108 (defvar parse-time-months '(("jan" . 1) ("feb" . 2) ("mar" . 3)
109 ("apr" . 4) ("may" . 5) ("jun" . 6)
110 ("jul" . 7) ("aug" . 8) ("sep" . 9)
111 ("oct" . 10) ("nov" . 11) ("dec" . 12)
112 ("january" . 1) ("february" . 2)
113 ("march" . 3) ("april" . 4) ("june" . 6)
114 ("july" . 7) ("august" . 8)
115 ("september" . 9) ("october" . 10)
116 ("november" . 11) ("december" . 12)))
117 (defvar parse-time-weekdays '(("sun" . 0) ("mon" . 1) ("tue" . 2)
118 ("wed" . 3) ("thu" . 4) ("fri" . 5)
119 ("sat" . 6) ("sunday" . 0) ("monday" . 1)
120 ("tuesday" . 2) ("wednesday" . 3)
121 ("thursday" . 4) ("friday" . 5)
123 (defvar parse-time-zoneinfo `(("z" 0) ("ut" 0) ("gmt" 0)
124 ("pst" ,(* -8 3600)) ("pdt" ,(* -7 3600) t)
125 ("mst" ,(* -7 3600)) ("mdt" ,(* -6 3600) t)
126 ("cst" ,(* -6 3600)) ("cdt" ,(* -5 3600) t)
127 ("est" ,(* -5 3600)) ("edt" ,(* -4 3600) t))
128 "(zoneinfo seconds-off daylight-savings-time-p)")
130 (defvar parse-time-rules
131 `(((6) parse-time-weekdays)
133 ((4) parse-time-months)
136 ,#'(lambda () (and (stringp parse-time-elt)
137 (= (length parse-time-elt) 8)
138 (= (aref parse-time-elt 2) ?:)
139 (= (aref parse-time-elt 5) ?:)))
141 ((8 7) parse-time-zoneinfo
142 ,#'(lambda () (car parse-time-val))
143 ,#'(lambda () (cadr parse-time-val)))
146 (and (stringp parse-time-elt)
147 (= 5 (length parse-time-elt))
148 (or (= (aref parse-time-elt 0) ?+)
149 (= (aref parse-time-elt 0) ?-))))
150 ,#'(lambda () (* 60 (+ (parse-integer parse-time-elt 3 5)
151 (* 60 (parse-integer parse-time-elt 1 3)))
152 (if (= (aref parse-time-elt 0) ?-) -1 1))))
154 ,#'(lambda () (and (stringp parse-time-elt)
155 (= (length parse-time-elt) 10)
156 (= (aref parse-time-elt 4) ?-)
157 (= (aref parse-time-elt 7) ?-)))
160 ,#'(lambda () (and (stringp parse-time-elt)
161 (= (length parse-time-elt) 5)
162 (= (aref parse-time-elt 2) ?:)))
163 [0 2] [3 5] ,#'(lambda () 0))
165 ,#'(lambda () (and (stringp parse-time-elt)
166 (= (length parse-time-elt) 4)
167 (= (aref parse-time-elt 1) ?:)))
168 [0 1] [2 4] ,#'(lambda () 0))
170 ,#'(lambda () (and (stringp parse-time-elt)
171 (= (length parse-time-elt) 7)
172 (= (aref parse-time-elt 1) ?:)))
174 ((5) (50 110) ,#'(lambda () (+ 1900 parse-time-elt)))
175 ((5) (0 49) ,#'(lambda () (+ 2000 parse-time-elt))))
176 "(slots predicate extractor...)")
177 ;;;###autoload(put 'parse-time-rules 'risky-local-variable t)
180 (defun parse-time-string (string)
181 "Parse the time-string STRING into (SEC MIN HOUR DAY MON YEAR DOW DST TZ).
182 The values are identical to those of `decode-time', but any values that are
183 unknown are returned as nil."
184 (let ((time (list nil nil nil nil nil nil nil nil nil))
185 (temp (parse-time-tokenize (downcase string))))
187 (let ((parse-time-elt (pop temp))
188 (rules parse-time-rules)
190 (while (and rules (not exit))
191 (let* ((rule (pop rules))
193 (predicate (pop rule))
195 (when (and (not (nth (car slots) time)) ;not already set
197 (cond ((and (consp predicate)
198 (not (eq (car predicate)
200 (and (numberp parse-time-elt)
201 (<= (car predicate) parse-time-elt)
202 (<= parse-time-elt (cadr predicate))
205 (cdr (assoc parse-time-elt
206 (symbol-value predicate))))
207 ((funcall predicate)))))
210 (let ((new-val (if rule
211 (let ((this (pop rule)))
215 (aref this 0) (aref this 1))
218 (rplaca (nthcdr (pop slots) time) new-val))))))))
221 (provide 'parse-time)
223 ;;; parse-time.el ends here