1 ;;; parse-time.el --- parsing time strings
3 ;; Copyright (C) 1996, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
4 ;; 2008, 2009, 2010 Free Software Foundation, Inc.
6 ;; Author: Erik Naggum <erik@naggum.no>
9 ;; This file is part of GNU Emacs.
11 ;; GNU Emacs is free software: you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation, either version 3 of the License, or
14 ;; (at your option) any later version.
16 ;; GNU Emacs is distributed in the hope that it will be useful,
17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 ;; GNU General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
26 ;; With the introduction of the `encode-time', `decode-time', and
27 ;; `format-time-string' functions, dealing with time became simpler in
28 ;; Emacs. However, parsing time strings is still largely a matter of
29 ;; heuristics and no common interface has been designed.
31 ;; `parse-time-string' parses a time in a string and returns a list of 9
32 ;; values, just like `decode-time', where unspecified elements in the
33 ;; string are returned as nil. `encode-time' may be applied on these
34 ;; values to obtain an internal time value.
38 (eval-when-compile (require 'cl
)) ;and ah ain't kiddin' 'bout it
41 (when (featurep 'xemacs
)
42 (defvar parse-time-syntax
(make-vector 256 nil
))))
43 (defvar parse-time-digits
(make-vector 256 nil
))
45 ;; Byte-compiler warnings
46 (defvar parse-time-elt
)
47 (defvar parse-time-val
)
49 (unless (aref parse-time-digits ?
0)
50 (loop for i from ?
0 to ?
9
51 do
(aset parse-time-digits i
(- i ?
0))))
53 (when (featurep 'xemacs
)
54 (unless (aref parse-time-syntax ?
0)
55 (loop for i from ?
0 to ?
9
56 do
(aset parse-time-syntax i ?
0))
57 (loop for i from ?A to ?Z
58 do
(aset parse-time-syntax i ?A
))
59 (loop for i from ?a to ?z
60 do
(aset parse-time-syntax i ?a
))
61 (aset parse-time-syntax ?
+ 1)
62 (aset parse-time-syntax ?- -
1)
63 (aset parse-time-syntax ?
: ?d
)))
65 (defsubst digit-char-p
(char)
66 (aref parse-time-digits char
))
69 (if (featurep 'xemacs
)
70 (defsubst parse-time-string-chars
(char)
71 (and (< char
(length parse-time-syntax
))
72 (aref parse-time-syntax char
)))
73 (defsubst parse-time-string-chars
(char)
75 (let (case-fold-search str
)
76 (cond ((eq char ?
+) 1)
79 ((string-match "[[:upper:]]" (setq str
(string char
))) ?A
)
80 ((string-match "[[:lower:]]" str
) ?a
)
81 ((string-match "[[:digit:]]" str
) ?
0)))))))
83 (put 'parse-error
'error-conditions
'(parse-error error
))
84 (put 'parse-error
'error-message
"Parsing error")
86 (defsubst parse-integer
(string &optional start end
)
87 "[CL] Parse and return the integer in STRING, or nil if none."
91 (end (or end
(length string
))))
93 (let ((sign (aref string index
)))
94 (if (or (eq sign ?
+) (eq sign ?-
))
95 (setq sign
(parse-time-string-chars sign
)
98 (while (and (< index end
)
99 (setq digit
(digit-char-p (aref string index
))))
100 (setq integer
(+ (* integer
10) digit
)
103 (signal 'parse-error
`("not an integer"
104 ,(substring string
(or start
0) end
)))
105 (* sign integer
))))))
107 (defun parse-time-tokenize (string)
108 "Tokenize STRING into substrings."
110 (end (length string
))
116 (while (and (< index end
) ;skip invalid characters
117 (not (setq c
(parse-time-string-chars (aref string index
)))))
119 (setq start index all-digits
(eq c ?
0))
120 (while (and (< (incf index
) end
) ;scan valid characters
121 (setq c
(parse-time-string-chars (aref string index
))))
122 (setq all-digits
(and all-digits
(eq c ?
0))))
124 (push (if all-digits
(parse-integer string start index
)
125 (substring string start index
))
129 (defvar parse-time-months
'(("jan" .
1) ("feb" .
2) ("mar" .
3)
130 ("apr" .
4) ("may" .
5) ("jun" .
6)
131 ("jul" .
7) ("aug" .
8) ("sep" .
9)
132 ("oct" .
10) ("nov" .
11) ("dec" .
12)
133 ("january" .
1) ("february" .
2)
134 ("march" .
3) ("april" .
4) ("june" .
6)
135 ("july" .
7) ("august" .
8)
136 ("september" .
9) ("october" .
10)
137 ("november" .
11) ("december" .
12)))
138 (defvar parse-time-weekdays
'(("sun" .
0) ("mon" .
1) ("tue" .
2)
139 ("wed" .
3) ("thu" .
4) ("fri" .
5)
140 ("sat" .
6) ("sunday" .
0) ("monday" .
1)
141 ("tuesday" .
2) ("wednesday" .
3)
142 ("thursday" .
4) ("friday" .
5)
144 (defvar parse-time-zoneinfo
`(("z" 0) ("ut" 0) ("gmt" 0)
145 ("pst" ,(* -
8 3600)) ("pdt" ,(* -
7 3600) t
)
146 ("mst" ,(* -
7 3600)) ("mdt" ,(* -
6 3600) t
)
147 ("cst" ,(* -
6 3600)) ("cdt" ,(* -
5 3600) t
)
148 ("est" ,(* -
5 3600)) ("edt" ,(* -
4 3600) t
))
149 "(zoneinfo seconds-off daylight-savings-time-p)")
151 (defvar parse-time-rules
152 `(((6) parse-time-weekdays
)
154 ((4) parse-time-months
)
157 ,#'(lambda () (and (stringp parse-time-elt
)
158 (= (length parse-time-elt
) 8)
159 (= (aref parse-time-elt
2) ?
:)
160 (= (aref parse-time-elt
5) ?
:)))
162 ((8 7) parse-time-zoneinfo
163 ,#'(lambda () (car parse-time-val
))
164 ,#'(lambda () (cadr parse-time-val
)))
167 (and (stringp parse-time-elt
)
168 (= 5 (length parse-time-elt
))
169 (or (= (aref parse-time-elt
0) ?
+)
170 (= (aref parse-time-elt
0) ?-
))))
171 ,#'(lambda () (* 60 (+ (parse-integer parse-time-elt
3 5)
172 (* 60 (parse-integer parse-time-elt
1 3)))
173 (if (= (aref parse-time-elt
0) ?-
) -
1 1))))
175 ,#'(lambda () (and (stringp parse-time-elt
)
176 (= (length parse-time-elt
) 10)
177 (= (aref parse-time-elt
4) ?-
)
178 (= (aref parse-time-elt
7) ?-
)))
181 ,#'(lambda () (and (stringp parse-time-elt
)
182 (= (length parse-time-elt
) 5)
183 (= (aref parse-time-elt
2) ?
:)))
184 [0 2] [3 5] ,#'(lambda () 0))
186 ,#'(lambda () (and (stringp parse-time-elt
)
187 (= (length parse-time-elt
) 4)
188 (= (aref parse-time-elt
1) ?
:)))
189 [0 1] [2 4] ,#'(lambda () 0))
191 ,#'(lambda () (and (stringp parse-time-elt
)
192 (= (length parse-time-elt
) 7)
193 (= (aref parse-time-elt
1) ?
:)))
195 ((5) (50 110) ,#'(lambda () (+ 1900 parse-time-elt
)))
196 ((5) (0 49) ,#'(lambda () (+ 2000 parse-time-elt
))))
197 "(slots predicate extractor...)")
198 ;;;###autoload(put 'parse-time-rules 'risky-local-variable t)
201 (defun parse-time-string (string)
202 "Parse the time-string STRING into (SEC MIN HOUR DAY MON YEAR DOW DST TZ).
203 The values are identical to those of `decode-time', but any values that are
204 unknown are returned as nil."
205 (let ((time (list nil nil nil nil nil nil nil nil nil
))
206 (temp (parse-time-tokenize (downcase string
))))
208 (let ((parse-time-elt (pop temp
))
209 (rules parse-time-rules
)
211 (while (and rules
(not exit
))
212 (let* ((rule (pop rules
))
214 (predicate (pop rule
))
216 (when (and (not (nth (car slots
) time
)) ;not already set
217 (setq parse-time-val
(cond ((and (consp predicate
)
218 (not (eq (car predicate
)
220 (and (numberp parse-time-elt
)
221 (<= (car predicate
) parse-time-elt
)
222 (<= parse-time-elt
(cadr predicate
))
225 (cdr (assoc parse-time-elt
226 (symbol-value predicate
))))
227 ((funcall predicate
)))))
230 (let ((new-val (and rule
231 (let ((this (pop rule
)))
235 (aref this
0) (aref this
1))
237 (rplaca (nthcdr (pop slots
) time
)
238 (or new-val parse-time-val
)))))))))
241 (provide 'parse-time
)
243 ;;; parse-time.el ends here