lisp/time-stamp.el

   1 ;;; time-stamp.el --- Maintain last change time stamps in files edited by Emacs
   2
   3 ;; Copyright (C) 1989, 1993, 1994, 1995, 1997, 2000, 2001, 2002, 2003,
   4 ;;   2004, 2005, 2006 Free Software Foundation, Inc.
   5
   6 ;; This file is part of GNU Emacs.
   7
   8 ;; Maintainer's Time-stamp: <2006-04-12 20:30:56 rms>
   9 ;; Maintainer: Stephen Gildea <gildea@stop.mail-abuse.org>
  10 ;; Keywords: tools
  11
  12 ;; GNU Emacs is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 2, or (at your option)
  15 ;; any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; A template in a file can be updated with a new time stamp when
  30 ;; you save the file.  For example:
  31 ;;     static char *ts = "sdmain.c Time-stamp: <2001-08-13 10:20:51 gildea>";
  32 ;; See the top of `time-stamp.el' for another example.
  33
  34 ;; To use time-stamping, add this line to your .emacs file:
  35 ;;     (add-hook 'before-save-hook 'time-stamp)
  36 ;; Now any time-stamp templates in your files will be updated automatically.
  37
  38 ;; See the documentation for the functions `time-stamp'
  39 ;; and `time-stamp-toggle-active' for details.
  40
  41 ;;; Code:
  42
  43 (defgroup time-stamp nil
  44   "Maintain last change time stamps in files edited by Emacs."
  45   :group 'data
  46   :group 'extensions)
  47
  48 (defcustom time-stamp-format "%:y-%02m-%02d %02H:%02M:%02S %u"
  49   "*Format of the string inserted by \\[time-stamp].
  50 The value may be a string or a list.  Lists are supported only for
  51 backward compatibility; see variable `time-stamp-old-format-warn'.
  52
  53 A string is used verbatim except for character sequences beginning
  54 with %, as follows.  The values of non-numeric formatted items depend
  55 on the locale setting recorded in `system-time-locale' and
  56 `locale-coding-system'.  The examples here are for the default
  57 \(`C') locale.
  58
  59 %:a  weekday name: `Monday'.            %#A gives uppercase: `MONDAY'
  60 %3a  abbreviated weekday: `Mon'.        %3A gives uppercase: `MON'
  61 %:b  month name: `January'.             %#B gives uppercase: `JANUARY'
  62 %3b  abbreviated month: `Jan'.          %3B gives uppercase: `JAN'
  63 %02d day of month
  64 %02H 24-hour clock hour
  65 %02I 12-hour clock hour
  66 %02m month number
  67 %02M minute
  68 %#p  `am' or `pm'.                      %P  gives uppercase: `AM' or `PM'
  69 %02S seconds
  70 %w   day number of week, Sunday is 0
  71 %02y 2-digit year: `03'                 %:y 4-digit year: `2003'
  72 %z   time zone name: `est'.             %Z  gives uppercase: `EST'
  73
  74 Non-date items:
  75 %%   a literal percent character: `%'
  76 %f   file name without directory        %F  gives absolute pathname
  77 %s   system name
  78 %u   user's login name                  %U  user's full name
  79 %h   mail host name
  80
  81 Decimal digits between the % and the type character specify the
  82 field width.  Strings are truncated on the right; years on the left.
  83 A leading zero in the field width zero-fills a number.
  84
  85 For example, to get the format used by the `date' command,
  86 use \"%3a %3b %2d %02H:%02M:%02S %Z %:y\".
  87
  88 In the future these formats will be aligned more with `format-time-string'.
  89 Because of this transition, the default padding for numeric formats will
  90 change in a future version.  Therefore either a padding width should be
  91 specified, or the : modifier should be used to explicitly request the
  92 historical default."
  93   :type 'string
  94   :group 'time-stamp
  95   :version "20.1")
  96 ;;;###autoload(put 'time-stamp-format 'safe-local-variable 'stringp)
  97
  98 (defcustom time-stamp-active t
  99   "*Non-nil to enable time-stamping of buffers by \\[time-stamp].
 100 Can be toggled by \\[time-stamp-toggle-active].
 101 See also the variable `time-stamp-warn-inactive'."
 102   :type 'boolean
 103   :group 'time-stamp)
 104
 105 (defcustom time-stamp-warn-inactive t
 106   "Have \\[time-stamp] warn if a buffer did not get time-stamped.
 107 If non-nil, a warning is displayed if `time-stamp-active' has
 108 deactivated time stamping and the buffer contains a template that
 109 otherwise would have been updated."
 110   :type 'boolean
 111   :group 'time-stamp
 112   :version "19.29")
 113
 114 (defcustom time-stamp-old-format-warn 'ask
 115   "Action if `time-stamp-format' is an old-style list.
 116 If `error', the format is not used.  If `ask', the user is queried about
 117 using the time-stamp-format.  If `warn', a warning is displayed.
 118 If nil, no notification is given."
 119   :type '(choice (const :tag "Don't use the format" error)
 120                  (const ask)
 121                  (const warn)
 122                  (const :tag "No notification" nil))
 123   :group 'time-stamp)
 124
 125 (defcustom time-stamp-time-zone nil
 126   "If non-nil, a string naming the timezone to be used by \\[time-stamp].
 127 Format is the same as that used by the environment variable TZ on your system."
 128   :type '(choice (const nil) string)
 129   :group 'time-stamp
 130   :version "20.1")
 131
 132
 133 ;;; Do not change time-stamp-line-limit, time-stamp-start,
 134 ;;; time-stamp-end, time-stamp-pattern, time-stamp-inserts-lines,
 135 ;;; or time-stamp-count in your .emacs or you will be incompatible
 136 ;;; with other people's files!  If you must change them, do so only
 137 ;;; in the local variables section of the file itself.
 138
 139
 140 (defvar time-stamp-line-limit 8     ;Do not change!
 141   "Lines of a file searched; positive counts from start, negative from end.
 142 The patterns `time-stamp-start' and `time-stamp-end' must be found in
 143 the first (last) `time-stamp-line-limit' lines of the file for the
 144 file to be time-stamped by \\[time-stamp].  A value of 0 searches the
 145 entire buffer (use with care).
 146
 147 This value can also be set with the variable `time-stamp-pattern'.
 148
 149 Do not change `time-stamp-line-limit', `time-stamp-start',
 150 `time-stamp-end', or `time-stamp-pattern' for yourself or you will be
 151 incompatible with other people's files!  If you must change them for some
 152 application, do so in the local variables section of the time-stamped file
 153 itself.")
 154 ;;;###autoload(put 'time-stamp-line-limit 'safe-local-variable 'integerp)
 155
 156 (defvar time-stamp-start "Time-stamp:[ \t]+\\\\?[\"<]+"    ;Do not change!
 157   "Regexp after which the time stamp is written by \\[time-stamp].
 158 See also the variables `time-stamp-end' and `time-stamp-line-limit'.
 159
 160 This value can also be set with the variable `time-stamp-pattern'.
 161
 162 Do not change `time-stamp-line-limit', `time-stamp-start',
 163 `time-stamp-end', or `time-stamp-pattern' for yourself or you will be
 164 incompatible with other people's files!  If you must change them for some
 165 application, do so in the local variables section of the time-stamped file
 166 itself.")
 167 ;;;###autoload(put 'time-stamp-start 'safe-local-variable 'stringp)
 168
 169 (defvar time-stamp-end "\\\\?[\">]"    ;Do not change!
 170   "Regexp marking the text after the time stamp.
 171 \\[time-stamp] deletes the text between the first match of `time-stamp-start'
 172 and the following match of `time-stamp-end', then writes the
 173 time stamp specified by `time-stamp-format' between them.
 174
 175 This value can also be set with the variable `time-stamp-pattern'.
 176
 177 The end text normally starts on the same line as the start text ends,
 178 but if there are any newlines in `time-stamp-format', the same number
 179 of newlines must separate the start and end.  \\[time-stamp] tries
 180 to not change the number of lines in the buffer.  `time-stamp-inserts-lines'
 181 controls this behavior.
 182
 183 Do not change `time-stamp-start', `time-stamp-end', `time-stamp-pattern',
 184 or `time-stamp-inserts-lines' for yourself or you will be incompatible
 185 with other people's files!  If you must change them for some application,
 186 do so in the local variables section of the time-stamped file itself.")
 187 ;;;###autoload(put 'time-stamp-end 'safe-local-variable 'stringp)
 188
 189
 190 (defvar time-stamp-inserts-lines nil    ;Do not change!
 191   "Whether \\[time-stamp] can change the number of lines in a file.
 192 If nil, \\[time-stamp] skips as many lines as there are newlines in
 193 `time-stamp-format' before looking for the `time-stamp-end' pattern,
 194 thus it tries not to change the number of lines in the buffer.
 195 If non-nil, \\[time-stamp] starts looking for the end pattern
 196 immediately after the start pattern.  This behavior can cause
 197 unexpected changes in the buffer if used carelessly, but it is useful
 198 for generating repeated time stamps.
 199
 200 Do not change `time-stamp-end' or `time-stamp-inserts-lines' for
 201 yourself or you will be incompatible with other people's files!
 202 If you must change them for some application, do so in the local
 203 variables section of the time-stamped file itself.")
 204 ;;;###autoload(put 'time-stamp-inserts-lines 'safe-local-variable 'symbolp)
 205
 206
 207 (defvar time-stamp-count 1              ;Do not change!
 208   "How many templates \\[time-stamp] will look for in a buffer.
 209 The same time stamp will be written in each case.
 210
 211 Do not change `time-stamp-count' for yourself or you will be
 212 incompatible with other people's files!  If you must change it for
 213 some application, do so in the local variables section of the
 214 time-stamped file itself.")
 215 ;;;###autoload(put 'time-stamp-count 'safe-local-variable 'integerp)
 216
 217
 218 (defvar time-stamp-pattern nil          ;Do not change!
 219   "Convenience variable setting all `time-stamp' location and format values.
 220 This string has four parts, each of which is optional.
 221 These four parts set `time-stamp-line-limit', `time-stamp-start',
 222 `time-stamp-format', and `time-stamp-end'.  See the documentation
 223 for each of these variables for details.
 224
 225 The first part is a number followed by a slash; the number sets the number
 226 of lines at the beginning (negative counts from end) of the file searched
 227 for the time stamp.  The number and the slash may be omitted to use the
 228 normal value.
 229
 230 The second part is a regexp identifying the pattern preceding the time stamp.
 231 This part may be omitted to use the normal pattern.
 232
 233 The third part specifies the format of the time stamp inserted.  See
 234 the documentation for `time-stamp-format' for details.  Specify this
 235 part as \"%%\" to use the normal format.
 236
 237 The fourth part is a regexp identifying the pattern following the time stamp.
 238 This part may be omitted to use the normal pattern.
 239
 240 Examples:
 241 \"-10/\"
 242 \"-9/^Last modified: %%$\"
 243 \"@set Time-stamp: %:b %:d, %:y$\"
 244 \"newcommand{\\\\\\\\timestamp}{%%}\"
 245
 246 Do not change `time-stamp-pattern' `time-stamp-line-limit',
 247 `time-stamp-start', or `time-stamp-end' for yourself or you will be
 248 incompatible with other people's files!  If you must change them for
 249 some application, do so only in the local variables section of the
 250 time-stamped file itself.")
 251 ;;;###autoload(put 'time-stamp-pattern 'safe-local-variable 'stringp)
 252
 253
 254
 255 ;;;###autoload
 256 (defun time-stamp ()
 257   "Update the time stamp string(s) in the buffer.
 258 A template in a file can be automatically updated with a new time stamp
 259 every time you save the file.  Add this line to your .emacs file:
 260     (add-hook 'before-save-hook 'time-stamp)
 261 or customize `before-save-hook' through Custom.
 262 Normally the template must appear in the first 8 lines of a file and
 263 look like one of the following:
 264       Time-stamp: <>
 265       Time-stamp: \" \"
 266 The time stamp is written between the brackets or quotes:
 267       Time-stamp: <2001-02-18 10:20:51 gildea>
 268 The time stamp is updated only if the variable `time-stamp-active' is non-nil.
 269 The format of the time stamp is set by the variable `time-stamp-pattern' or
 270 `time-stamp-format'.  The variables `time-stamp-pattern',
 271 `time-stamp-line-limit', `time-stamp-start', `time-stamp-end',
 272 `time-stamp-count', and `time-stamp-inserts-lines' control finding
 273 the template."
 274   (interactive)
 275   (let ((line-limit time-stamp-line-limit)
 276         (ts-start time-stamp-start)
 277         (ts-format time-stamp-format)
 278         (ts-end time-stamp-end)
 279         (ts-count time-stamp-count)
 280         (format-lines 0)
 281         (end-lines 1)
 282         (start nil)
 283         search-limit)
 284     (if (stringp time-stamp-pattern)
 285         (progn
 286           (string-match "\\`\\(\\(-?[0-9]+\\)/\\)?\\([^%]+\\)?\\(\\(%[-.,:@+_ #^()0-9]*[A-Za-z%][^%]*\\)*%[-.,:@+_ #^()0-9]*[A-Za-z%]\\)?\\([^%]+\\)?\\'" time-stamp-pattern)
 287           (and (match-beginning 2)
 288                (setq line-limit
 289                      (string-to-number (match-string 2 time-stamp-pattern))))
 290           (and (match-beginning 3)
 291                (setq ts-start (match-string 3 time-stamp-pattern)))
 292           (and (match-beginning 4)
 293                (not (string-equal (match-string 4 time-stamp-pattern) "%%"))
 294                (setq ts-format (match-string 4 time-stamp-pattern)))
 295           (and (match-beginning 6)
 296                (setq ts-end (match-string 6 time-stamp-pattern)))))
 297     (cond ((not (integerp line-limit))
 298            (setq line-limit 8)
 299            (message "time-stamp-line-limit is not an integer")
 300            (sit-for 1)))
 301     (cond ((not (integerp ts-count))
 302            (setq ts-count 1)
 303            (message "time-stamp-count is not an integer")
 304            (sit-for 1))
 305           ((< ts-count 1)
 306            ;; We need to call time-stamp-once at least once
 307            ;; to output any warnings about time-stamp not being active.
 308            (setq ts-count 1)))
 309     ;; Figure out what lines the end should be on.
 310     (if (stringp ts-format)
 311         (let ((nl-start 0))
 312           (while (string-match "\n" ts-format nl-start)
 313             (setq format-lines (1+ format-lines) nl-start (match-end 0)))))
 314     (let ((nl-start 0))
 315       (while (string-match "\n" ts-end nl-start)
 316         (setq end-lines (1+ end-lines) nl-start (match-end 0))))
 317     ;; Find overall what lines to look at
 318     (save-excursion
 319       (save-restriction
 320         (widen)
 321         (cond ((> line-limit 0)
 322                (goto-char (setq start (point-min)))
 323                (forward-line line-limit)
 324                (setq search-limit (point)))
 325               ((< line-limit 0)
 326                (goto-char (setq search-limit (point-max)))
 327                (forward-line line-limit)
 328                (setq start (point)))
 329               (t                        ;0 => no limit (use with care!)
 330                (setq start (point-min))
 331                (setq search-limit (point-max))))))
 332     (while (and start
 333                 (< start search-limit)
 334                 (> ts-count 0))
 335       (setq start (time-stamp-once start search-limit ts-start ts-end
 336                                    ts-format format-lines end-lines))
 337       (setq ts-count (1- ts-count))))
 338   nil)
 339
 340 (defun time-stamp-once (start search-limit ts-start ts-end
 341                         ts-format format-lines end-lines)
 342   "Update one time stamp.  Internal routine called by \\[time-stamp].
 343 Returns the end point, which is where `time-stamp' begins the next search."
 344   (let ((case-fold-search nil)
 345         (end nil)
 346         end-search-start
 347         (end-length nil))
 348     (save-excursion
 349       (save-restriction
 350         (widen)
 351         ;; Find the location of the time stamp.
 352         (while (and (< (goto-char start) search-limit)
 353                     (not end)
 354                     (re-search-forward ts-start search-limit 'move))
 355           (setq start (point))
 356           (if (not time-stamp-inserts-lines)
 357               (forward-line format-lines))
 358           (setq end-search-start (max start (point)))
 359           (if (= (forward-line end-lines) 0)
 360               (progn
 361                (and (bolp) (backward-char))
 362                (let ((line-end (min (point) search-limit)))
 363                  (if (>= line-end end-search-start)
 364                      (progn
 365                       (goto-char end-search-start)
 366                       (if (re-search-forward ts-end line-end t)
 367                           (progn
 368                             (setq end (match-beginning 0))
 369                             (setq end-length (- (match-end 0) end))))))))))))
 370     (if end
 371         (progn
 372           ;; do all warnings outside save-excursion
 373           (cond
 374            ((not time-stamp-active)
 375             (if time-stamp-warn-inactive
 376                 ;; don't signal an error in a write-file-hook
 377                 (progn
 378                   (message "Warning: time-stamp-active is off; did not time-stamp buffer.")
 379                   (sit-for 1))))
 380            ((not (and (stringp ts-start)
 381                       (stringp ts-end)))
 382             (message "time-stamp-start or time-stamp-end is not a string")
 383             (sit-for 1))
 384            (t
 385             (let ((new-time-stamp (time-stamp-string ts-format)))
 386               (if (and (stringp new-time-stamp)
 387                        (not (string-equal (buffer-substring start end)
 388                                           new-time-stamp)))
 389                   (save-excursion
 390                     (save-restriction
 391                       (widen)
 392                       (delete-region start end)
 393                       (goto-char start)
 394                       (insert-and-inherit new-time-stamp)
 395                       (setq end (point))
 396                       ;; remove any tabs used to format time stamp
 397                       (if (search-backward "\t" start t)
 398                           (progn
 399                             (untabify start end)
 400                             (setq end (point))))))))))))
 401     ;; return the location after this time stamp, if there was one
 402     (and end end-length
 403          (+ end end-length))))
 404
 405
 406 ;;;###autoload
 407 (defun time-stamp-toggle-active (&optional arg)
 408   "Toggle `time-stamp-active', setting whether \\[time-stamp] updates a buffer.
 409 With ARG, turn time stamping on if and only if arg is positive."
 410   (interactive "P")
 411   (setq time-stamp-active
 412         (if (null arg)
 413             (not time-stamp-active)
 414           (> (prefix-numeric-value arg) 0)))
 415   (message "time-stamp is now %s." (if time-stamp-active "active" "off")))
 416
 417
 418 (defun time-stamp-string (&optional ts-format)
 419   "Generate the new string to be inserted by \\[time-stamp].
 420 Optionally use format TS-FORMAT instead of `time-stamp-format' to
 421 format the string."
 422   (or ts-format
 423       (setq ts-format time-stamp-format))
 424   (if (stringp ts-format)
 425       (if (stringp time-stamp-time-zone)
 426           (let ((ts-real-time-zone (getenv "TZ")))
 427             (unwind-protect
 428                 (progn
 429                   (set-time-zone-rule time-stamp-time-zone)
 430                   (format-time-string
 431                    (time-stamp-string-preprocess ts-format)))
 432               (set-time-zone-rule ts-real-time-zone)))
 433         (format-time-string
 434          (time-stamp-string-preprocess ts-format)))
 435     ;; handle version 1 compatibility
 436     (cond ((or (eq time-stamp-old-format-warn 'error)
 437                (and (eq time-stamp-old-format-warn 'ask)
 438                     (not (y-or-n-p "Use non-string time-stamp-format? "))))
 439            (message "Warning: no time-stamp: time-stamp-format not a string")
 440            (sit-for 1)
 441            nil)
 442           (t
 443            (cond ((eq time-stamp-old-format-warn 'warn)
 444                   (message "Obsolescent time-stamp-format type; should be string")
 445                   (sit-for 1)))
 446            (time-stamp-fconcat ts-format " ")))))
 447
 448 (defconst time-stamp-no-file "(no file)"
 449   "String to use when the buffer is not associated with a file.")
 450
 451 ;;; time-stamp is transitioning to using the new, expanded capabilities
 452 ;;; of format-time-string.  During the process, this function implements
 453 ;;; intermediate, compatible formats and complains about old, soon to
 454 ;;; be unsupported, formats.  This function will get a lot (a LOT) shorter
 455 ;;; when the transition is complete and we can just pass most things
 456 ;;; straight through to format-time-string.
 457 ;;;      At all times, all the formats recommended in the doc string
 458 ;;; of time-stamp-format will work not only in the current version of
 459 ;;; Emacs, but in all versions that have been released within the past
 460 ;;; two years.
 461 ;;;      The : modifier is a temporary conversion feature used to resolve
 462 ;;; ambiguous formats--formats that are changing (over time) incompatibly.
 463 (defun time-stamp-string-preprocess (format &optional time)
 464   "Use a FORMAT to format date, time, file, and user information.
 465 Optional second argument TIME is only for testing.
 466 Implements non-time extensions to `format-time-string'
 467 and all `time-stamp-format' compatibility."
 468   (let ((fmt-len (length format))
 469         (ind 0)
 470         cur-char
 471         (prev-char nil)
 472         (result "")
 473         field-width
 474         field-result
 475         alt-form change-case require-padding
 476         (paren-level 0))
 477     (while (< ind fmt-len)
 478       (setq cur-char (aref format ind))
 479       (setq
 480        result
 481        (concat result
 482       (cond
 483        ((eq cur-char ?%)
 484         ;; eat any additional args to allow for future expansion
 485         (setq alt-form nil change-case nil require-padding nil field-width "")
 486         (while (progn
 487                  (setq ind (1+ ind))
 488                  (setq cur-char (if (< ind fmt-len)
 489                                     (aref format ind)
 490                                   ?\0))
 491                  (or (eq ?. cur-char)
 492                      (eq ?, cur-char) (eq ?: cur-char) (eq ?@ cur-char)
 493                      (eq ?- cur-char) (eq ?+ cur-char) (eq ?_ cur-char)
 494                      (eq ?\s cur-char) (eq ?# cur-char) (eq ?^ cur-char)
 495                      (and (eq ?\( cur-char)
 496                           (not (eq prev-char ?\\))
 497                           (setq paren-level (1+ paren-level)))
 498                      (if (and (eq ?\) cur-char)
 499                               (not (eq prev-char ?\\))
 500                               (> paren-level 0))
 501                          (setq paren-level (1- paren-level))
 502                        (and (> paren-level 0)
 503                             (< ind fmt-len)))
 504                      (if (and (<= ?0 cur-char) (>= ?9 cur-char))
 505                          ;; get format width
 506                          (let ((field-index ind))
 507                            (while (progn
 508                                     (setq ind (1+ ind))
 509                                     (setq cur-char (if (< ind fmt-len)
 510                                                        (aref format ind)
 511                                                      ?\0))
 512                                     (and (<= ?0 cur-char) (>= ?9 cur-char))))
 513                            (setq field-width (substring format field-index ind))
 514                            (setq ind (1- ind))
 515                            t))))
 516           (setq prev-char cur-char)
 517           ;; some characters we actually use
 518           (cond ((eq cur-char ?:)
 519                  (setq alt-form t))
 520                 ((eq cur-char ?#)
 521                  (setq change-case t))))
 522         (setq field-result
 523         (cond
 524          ((eq cur-char ?%)
 525           "%%")
 526          ((eq cur-char ?a)              ;day of week
 527           (if change-case
 528               (format-time-string "%#a" time)
 529             (or alt-form (not (string-equal field-width ""))
 530                 (time-stamp-conv-warn "%a" "%:a"))
 531             (if (and alt-form (not (string-equal field-width "")))
 532                 ""                      ;discourage "%:3a"
 533               (format-time-string "%A" time))))
 534          ((eq cur-char ?A)
 535           (if alt-form
 536               (format-time-string "%A" time)
 537             (or change-case (not (string-equal field-width ""))
 538                 (time-stamp-conv-warn "%A" "%#A"))
 539             (format-time-string "%#A" time)))
 540          ((eq cur-char ?b)              ;month name
 541           (if change-case
 542               (format-time-string "%#b" time)
 543             (or alt-form (not (string-equal field-width ""))
 544                 (time-stamp-conv-warn "%b" "%:b"))
 545             (if (and alt-form (not (string-equal field-width "")))
 546                 ""                      ;discourage "%:3b"
 547             (format-time-string "%B" time))))
 548          ((eq cur-char ?B)
 549           (if alt-form
 550               (format-time-string "%B" time)
 551             (or change-case (not (string-equal field-width ""))
 552                 (time-stamp-conv-warn "%B" "%#B"))
 553             (format-time-string "%#B" time)))
 554          ((eq cur-char ?d)              ;day of month, 1-31
 555           (time-stamp-do-number cur-char alt-form field-width time))
 556          ((eq cur-char ?H)              ;hour, 0-23
 557           (time-stamp-do-number cur-char alt-form field-width time))
 558          ((eq cur-char ?I)              ;hour, 1-12
 559           (time-stamp-do-number cur-char alt-form field-width time))
 560          ((eq cur-char ?m)              ;month number, 1-12
 561           (time-stamp-do-number cur-char alt-form field-width time))
 562          ((eq cur-char ?M)              ;minute, 0-59
 563           (time-stamp-do-number cur-char alt-form field-width time))
 564          ((eq cur-char ?p)              ;am or pm
 565           (or change-case
 566               (time-stamp-conv-warn "%p" "%#p"))
 567           (format-time-string "%#p" time))
 568          ((eq cur-char ?P)              ;AM or PM
 569           (format-time-string "%p" time))
 570          ((eq cur-char ?S)              ;seconds, 00-60
 571           (time-stamp-do-number cur-char alt-form field-width time))
 572          ((eq cur-char ?w)              ;weekday number, Sunday is 0
 573           (format-time-string "%w" time))
 574          ((eq cur-char ?y)              ;year
 575           (or alt-form (not (string-equal field-width ""))
 576               (time-stamp-conv-warn "%y" "%:y"))
 577           (string-to-number (format-time-string "%Y" time)))
 578          ((eq cur-char ?Y)              ;4-digit year, new style
 579           (string-to-number (format-time-string "%Y" time)))
 580          ((eq cur-char ?z)              ;time zone lower case
 581           (if change-case
 582               ""                        ;discourage %z variations
 583             (format-time-string "%#Z" time)))
 584          ((eq cur-char ?Z)
 585           (if change-case
 586               (format-time-string "%#Z" time)
 587             (format-time-string "%Z" time)))
 588          ((eq cur-char ?f)              ;buffer-file-name, base name only
 589           (if buffer-file-name
 590               (file-name-nondirectory buffer-file-name)
 591             time-stamp-no-file))
 592          ((eq cur-char ?F)              ;buffer-file-name, full path
 593           (or buffer-file-name
 594               time-stamp-no-file))
 595          ((eq cur-char ?s)              ;system name
 596           (system-name))
 597          ((eq cur-char ?u)              ;user name
 598           (user-login-name))
 599          ((eq cur-char ?U)              ;user full name
 600           (user-full-name))
 601          ((eq cur-char ?l)              ;logname (undocumented user name alt)
 602           (user-login-name))
 603          ((eq cur-char ?L)              ;(undocumented alt user full name)
 604           (user-full-name))
 605          ((eq cur-char ?h)              ;mail host name
 606           (time-stamp-mail-host-name))
 607          ((eq cur-char ?q)              ;(undocumented unqual hostname)
 608           (let ((qualname (system-name)))
 609             (if (string-match "\\." qualname)
 610                 (substring qualname 0 (match-beginning 0))
 611               qualname)))
 612          ((eq cur-char ?Q)              ;(undocumented fully-qualified host)
 613           (system-name))
 614          ))
 615         (let ((padded-result
 616                (format (format "%%%s%c"
 617                                field-width
 618                                (if (numberp field-result) ?d ?s))
 619                        (or field-result ""))))
 620           (let* ((initial-length (length padded-result))
 621                  (desired-length (if (string-equal field-width "")
 622                                      initial-length
 623                                    (string-to-number field-width))))
 624             (if (> initial-length desired-length)
 625                 ;; truncate strings on right, years on left
 626                 (if (stringp field-result)
 627                     (substring padded-result 0 desired-length)
 628                   (if (eq cur-char ?y)
 629                       (substring padded-result (- desired-length))
 630                     padded-result))     ;non-year numbers don't truncate
 631               padded-result))))
 632        (t
 633         (char-to-string cur-char)))))
 634       (setq ind (1+ ind)))
 635     result))
 636
 637 (defun time-stamp-do-number (format-char alt-form field-width time)
 638   "Handle compatible FORMAT-CHAR where only default width/padding will change.
 639 ALT-FORM is whether `#' specified.  FIELD-WIDTH is the string
 640 width specification or \"\".  TIME is the time to convert."
 641   (let ((format-string (concat "%" (char-to-string format-char))))
 642     (and (not alt-form) (string-equal field-width "")
 643          (time-stamp-conv-warn format-string
 644                                (format "%%:%c" format-char)))
 645     (if (and alt-form (not (string-equal field-width "")))
 646         ""                              ;discourage "%:2d" and the like
 647       (string-to-number (format-time-string format-string time)))))
 648
 649 (defvar time-stamp-conversion-warn t
 650   "Warn about soon-to-be-unsupported forms in `time-stamp-format'.
 651 If nil, these warnings are disabled, which would be a bad idea!
 652 You really need to update your files instead.
 653
 654 The new formats will work with old versions of Emacs.
 655 New formats are being recommended now to allow `time-stamp-format'
 656 to change in the future to be compatible with `format-time-string'.
 657 The new forms being recommended now will continue to work then.")
 658
 659
 660 (defun time-stamp-conv-warn (old-form new-form)
 661   "Display a warning about a soon-to-be-obsolete format.
 662 Suggests replacing OLD-FORM with NEW-FORM."
 663   (cond
 664    (time-stamp-conversion-warn
 665     (save-excursion
 666       (set-buffer (get-buffer-create "*Time-stamp-compatibility*"))
 667       (goto-char (point-max))
 668       (if (bobp)
 669           (progn
 670             (insert
 671              "The formats recognized in time-stamp-format will change in a future release\n"
 672              "to be compatible with the new, expanded format-time-string function.\n\n"
 673              "The following obsolescent time-stamp-format construct(s) were found:\n\n")))
 674       (insert "\"" old-form "\" -- use " new-form "\n"))
 675     (display-buffer "*Time-stamp-compatibility*"))))
 676
 677
 678
 679 (defun time-stamp-mail-host-name ()
 680   "Return the name of the host where the user receives mail.
 681 This is the value of `mail-host-address' if bound and a string,
 682 otherwise the value of the function `system-name'."
 683   (or (and (boundp 'mail-host-address)
 684            (stringp mail-host-address)
 685            mail-host-address)
 686       (system-name)))
 687
 688 ;;; the rest of this file is for version 1 compatibility
 689
 690 (defun time-stamp-fconcat (list sep)
 691   "Similar to (mapconcat 'funcall LIST SEP) but LIST allows literals.
 692 If an element of LIST is a symbol, it is funcalled to get the string to use;
 693 the separator SEP is used between two strings obtained by funcalling a
 694 symbol.  Otherwise the element itself is inserted; no separator is used
 695 around literals."
 696   (let ((return-string "")
 697         (insert-sep-p nil))
 698     (while list
 699       (cond ((symbolp (car list))
 700              (if insert-sep-p
 701                  (setq return-string (concat return-string sep)))
 702              (setq return-string (concat return-string (funcall (car list))))
 703              (setq insert-sep-p t))
 704             (t
 705              (setq return-string (concat return-string (car list)))
 706              (setq insert-sep-p nil)))
 707       (setq list (cdr list)))
 708     return-string))
 709
 710 ;;; Some functions used in time-stamp-format
 711
 712 ;;; These functions have been obsolete since 1995
 713 ;;; and will be removed in a future Emacs release.
 714 ;;; Meanwhile, discourage other packages from using them.
 715 (dolist (function '(time-stamp-month-dd-yyyy time-stamp-dd/mm/yyyy
 716                     time-stamp-mon-dd-yyyy   time-stamp-dd-mon-yy
 717                     time-stamp-yy/mm/dd      time-stamp-yyyy/mm/dd
 718                     time-stamp-yyyy-mm-dd    time-stamp-yymmdd
 719                     time-stamp-hh:mm:ss      time-stamp-hhmm))
 720   (make-obsolete function
 721                  "use `time-stamp-string' or `format-time-string' instead."
 722                  "20.1"))
 723
 724 ;;; pretty form, suitable for a title page
 725
 726 (defun time-stamp-month-dd-yyyy ()
 727   "Return the current date as a string in \"Month DD, YYYY\" form."
 728   (format-time-string "%B %e, %Y"))
 729
 730 (defun time-stamp-dd/mm/yyyy ()
 731   "Return the current date as a string in \"DD/MM/YYYY\" form."
 732   (format-time-string "%d/%m/%Y"))
 733
 734 ;;; same as __DATE__ in ANSI C
 735
 736 (defun time-stamp-mon-dd-yyyy ()
 737   "Return the current date as a string in \"Mon DD YYYY\" form.
 738 The first character of DD is space if the value is less than 10."
 739   (format-time-string "%b %d %Y"))
 740
 741 ;;; RFC 822 date
 742
 743 (defun time-stamp-dd-mon-yy ()
 744   "Return the current date as a string in \"DD Mon YY\" form."
 745   (format-time-string "%d %b %y"))
 746
 747 ;;; RCS 3 date
 748
 749 (defun time-stamp-yy/mm/dd ()
 750   "Return the current date as a string in \"YY/MM/DD\" form."
 751   (format-time-string "%y/%m/%d"))
 752
 753 ;;; RCS 5 date
 754
 755 (defun time-stamp-yyyy/mm/dd ()
 756   "Return the current date as a string in \"YYYY/MM/DD\" form."
 757   (format-time-string "%Y/%m/%d"))
 758
 759 ;;; ISO 8601 date
 760
 761 (defun time-stamp-yyyy-mm-dd ()
 762   "Return the current date as a string in \"YYYY-MM-DD\" form."
 763   (format-time-string "%Y-%m-%d"))
 764
 765 (defun time-stamp-yymmdd ()
 766   "Return the current date as a string in \"YYMMDD\" form."
 767   (format-time-string "%y%m%d"))
 768
 769 (defun time-stamp-hh:mm:ss ()
 770   "Return the current time as a string in \"HH:MM:SS\" form."
 771   (format-time-string "%T"))
 772
 773 (defun time-stamp-hhmm ()
 774   "Return the current time as a string in \"HHMM\" form."
 775   (format-time-string "%H%M"))
 776
 777 (provide 'time-stamp)
 778
 779 ;;; arch-tag: 8a12c5c3-25d6-4a71-adc5-24b0e025a1e7
 780 ;;; time-stamp.el ends here