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 Free Software Foundation, Inc.
   5
   6 ;; This file is part of GNU Emacs.
   7
   8 ;; Maintainer's Time-stamp: <2004-09-25 20:55:35 gildea>
   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
  97 (defcustom time-stamp-active t
  98   "*Non-nil to enable time-stamping of buffers by \\[time-stamp].
  99 Can be toggled by \\[time-stamp-toggle-active].
 100 See also the variable `time-stamp-warn-inactive'."
 101   :type 'boolean
 102   :group 'time-stamp)
 103
 104 (defcustom time-stamp-warn-inactive t
 105   "Have \\[time-stamp] warn if a buffer did not get time-stamped.
 106 If non-nil, a warning is displayed if `time-stamp-active' has
 107 deactivated time stamping and the buffer contains a template that
 108 otherwise would have been updated."
 109   :type 'boolean
 110   :group 'time-stamp
 111   :version "19.29")
 112
 113 (defcustom time-stamp-old-format-warn 'ask
 114   "Action if `time-stamp-format' is an old-style list.
 115 If `error', the format is not used.  If `ask', the user is queried about
 116 using the time-stamp-format.  If `warn', a warning is displayed.
 117 If nil, no notification is given."
 118   :type '(choice (const :tag "Don't use the format" error)
 119                  (const ask)
 120                  (const warn)
 121                  (const :tag "No notification" nil))
 122   :group 'time-stamp)
 123
 124 (defcustom time-stamp-time-zone nil
 125   "If non-nil, a string naming the timezone to be used by \\[time-stamp].
 126 Format is the same as that used by the environment variable TZ on your system."
 127   :type '(choice (const nil) string)
 128   :group 'time-stamp
 129   :version "20.1")
 130
 131
 132 ;;; Do not change time-stamp-line-limit, time-stamp-start,
 133 ;;; time-stamp-end, time-stamp-pattern, time-stamp-inserts-lines,
 134 ;;; or time-stamp-count in your .emacs or you will be incompatible
 135 ;;; with other people's files!  If you must change them, do so only
 136 ;;; in the local variables section of the file itself.
 137
 138
 139 (defvar time-stamp-line-limit 8     ;Do not change!
 140   "Lines of a file searched; positive counts from start, negative from end.
 141 The patterns `time-stamp-start' and `time-stamp-end' must be found in
 142 the first (last) `time-stamp-line-limit' lines of the file for the
 143 file to be time-stamped by \\[time-stamp].  A value of 0 searches the
 144 entire buffer (use with care).
 145
 146 This value can also be set with the variable `time-stamp-pattern'.
 147
 148 Do not change `time-stamp-line-limit', `time-stamp-start',
 149 `time-stamp-end', or `time-stamp-pattern' for yourself or you will be
 150 incompatible with other people's files!  If you must change them for some
 151 application, do so in the local variables section of the time-stamped file
 152 itself.")
 153
 154
 155 (defvar time-stamp-start "Time-stamp:[ \t]+\\\\?[\"<]+"    ;Do not change!
 156   "Regexp after which the time stamp is written by \\[time-stamp].
 157 See also the variables `time-stamp-end' and `time-stamp-line-limit'.
 158
 159 This value can also be set with the variable `time-stamp-pattern'.
 160
 161 Do not change `time-stamp-line-limit', `time-stamp-start',
 162 `time-stamp-end', or `time-stamp-pattern' for yourself or you will be
 163 incompatible with other people's files!  If you must change them for some
 164 application, do so in the local variables section of the time-stamped file
 165 itself.")
 166
 167
 168 (defvar time-stamp-end "\\\\?[\">]"    ;Do not change!
 169   "Regexp marking the text after the time stamp.
 170 \\[time-stamp] deletes the text between the first match of `time-stamp-start'
 171 and the following match of `time-stamp-end', then writes the
 172 time stamp specified by `time-stamp-format' between them.
 173
 174 This value can also be set with the variable `time-stamp-pattern'.
 175
 176 The end text normally starts on the same line as the start text ends,
 177 but if there are any newlines in `time-stamp-format', the same number
 178 of newlines must separate the start and end.  \\[time-stamp] tries
 179 to not change the number of lines in the buffer.  `time-stamp-inserts-lines'
 180 controls this behavior.
 181
 182 Do not change `time-stamp-start', `time-stamp-end', `time-stamp-pattern',
 183 or `time-stamp-inserts-lines' for yourself or you will be incompatible
 184 with other people's files!  If you must change them for some application,
 185 do so in the local variables section of the time-stamped file itself.")
 186
 187
 188 (defvar time-stamp-inserts-lines nil    ;Do not change!
 189   "Whether \\[time-stamp] can change the number of lines in a file.
 190 If nil, \\[time-stamp] skips as many lines as there are newlines in
 191 `time-stamp-format' before looking for the `time-stamp-end' pattern,
 192 thus it tries not to change the number of lines in the buffer.
 193 If non-nil, \\[time-stamp] starts looking for the end pattern
 194 immediately after the start pattern.  This behavior can cause
 195 unexpected changes in the buffer if used carelessly, but it is useful
 196 for generating repeated time stamps.
 197
 198 Do not change `time-stamp-end' or `time-stamp-inserts-lines' for
 199 yourself or you will be incompatible with other people's files!
 200 If you must change them for some application, do so in the local
 201 variables section of the time-stamped file itself.")
 202
 203
 204 (defvar time-stamp-count 1              ;Do not change!
 205   "How many templates \\[time-stamp] will look for in a buffer.
 206 The same time stamp will be written in each case.
 207
 208 Do not change `time-stamp-count' for yourself or you will be
 209 incompatible with other people's files!  If you must change it for
 210 some application, do so in the local variables section of the
 211 time-stamped file itself.")
 212
 213
 214 (defvar time-stamp-pattern nil          ;Do not change!
 215   "Convenience variable setting all `time-stamp' location and format values.
 216 This string has four parts, each of which is optional.
 217 These four parts set `time-stamp-line-limit', `time-stamp-start',
 218 `time-stamp-format', and `time-stamp-end'.  See the documentation
 219 for each of these variables for details.
 220
 221 The first part is a number followed by a slash; the number sets the number
 222 of lines at the beginning (negative counts from end) of the file searched
 223 for the time stamp.  The number and the slash may be omitted to use the
 224 normal value.
 225
 226 The second part is a regexp identifying the pattern preceding the time stamp.
 227 This part may be omitted to use the normal pattern.
 228
 229 The third part specifies the format of the time stamp inserted.  See
 230 the documentation for `time-stamp-format' for details.  Specify this
 231 part as \"%%\" to use the normal format.
 232
 233 The fourth part is a regexp identifying the pattern following the time stamp.
 234 This part may be omitted to use the normal pattern.
 235
 236 Examples:
 237 \"-10/\"
 238 \"-9/^Last modified: %%$\"
 239 \"@set Time-stamp: %:b %:d, %:y$\"
 240 \"newcommand{\\\\\\\\timestamp}{%%}\"
 241
 242 Do not change `time-stamp-pattern' `time-stamp-line-limit',
 243 `time-stamp-start', or `time-stamp-end' for yourself or you will be
 244 incompatible with other people's files!  If you must change them for
 245 some application, do so only in the local variables section of the
 246 time-stamped file itself.")
 247
 248
 249
 250 ;;;###autoload
 251 (defun time-stamp ()
 252   "Update the time stamp string(s) in the buffer.
 253 A template in a file can be automatically updated with a new time stamp
 254 every time you save the file.  Add this line to your .emacs file:
 255     (add-hook 'before-save-hook 'time-stamp)
 256 or customize `before-save-hook' through Custom.
 257 Normally the template must appear in the first 8 lines of a file and
 258 look like one of the following:
 259       Time-stamp: <>
 260       Time-stamp: \" \"
 261 The time stamp is written between the brackets or quotes:
 262       Time-stamp: <2001-02-18 10:20:51 gildea>
 263 The time stamp is updated only if the variable `time-stamp-active' is non-nil.
 264 The format of the time stamp is set by the variable `time-stamp-pattern' or
 265 `time-stamp-format'.  The variables `time-stamp-pattern',
 266 `time-stamp-line-limit', `time-stamp-start', `time-stamp-end',
 267 `time-stamp-count', and `time-stamp-inserts-lines' control finding
 268 the template."
 269   (interactive)
 270   (let ((line-limit time-stamp-line-limit)
 271         (ts-start time-stamp-start)
 272         (ts-format time-stamp-format)
 273         (ts-end time-stamp-end)
 274         (ts-count time-stamp-count)
 275         (format-lines 0)
 276         (end-lines 1)
 277         (start nil)
 278         search-limit)
 279     (if (stringp time-stamp-pattern)
 280         (progn
 281           (string-match "\\`\\(\\(-?[0-9]+\\)/\\)?\\([^%]+\\)?\\(\\(%[-.,:@+_ #^()0-9]*[A-Za-z%][^%]*\\)*%[-.,:@+_ #^()0-9]*[A-Za-z%]\\)?\\([^%]+\\)?\\'" time-stamp-pattern)
 282           (and (match-beginning 2)
 283                (setq line-limit
 284                      (string-to-number (match-string 2 time-stamp-pattern))))
 285           (and (match-beginning 3)
 286                (setq ts-start (match-string 3 time-stamp-pattern)))
 287           (and (match-beginning 4)
 288                (not (string-equal (match-string 4 time-stamp-pattern) "%%"))
 289                (setq ts-format (match-string 4 time-stamp-pattern)))
 290           (and (match-beginning 6)
 291                (setq ts-end (match-string 6 time-stamp-pattern)))))
 292     (cond ((not (integerp line-limit))
 293            (setq line-limit 8)
 294            (message "time-stamp-line-limit is not an integer")
 295            (sit-for 1)))
 296     (cond ((not (integerp ts-count))
 297            (setq ts-count 1)
 298            (message "time-stamp-count is not an integer")
 299            (sit-for 1))
 300           ((< ts-count 1)
 301            ;; We need to call time-stamp-once at least once
 302            ;; to output any warnings about time-stamp not being active.
 303            (setq ts-count 1)))
 304     ;; Figure out what lines the end should be on.
 305     (if (stringp ts-format)
 306         (let ((nl-start 0))
 307           (while (string-match "\n" ts-format nl-start)
 308             (setq format-lines (1+ format-lines) nl-start (match-end 0)))))
 309     (let ((nl-start 0))
 310       (while (string-match "\n" ts-end nl-start)
 311         (setq end-lines (1+ end-lines) nl-start (match-end 0))))
 312     ;; Find overall what lines to look at
 313     (save-excursion
 314       (save-restriction
 315         (widen)
 316         (cond ((> line-limit 0)
 317                (goto-char (setq start (point-min)))
 318                (forward-line line-limit)
 319                (setq search-limit (point)))
 320               ((< line-limit 0)
 321                (goto-char (setq search-limit (point-max)))
 322                (forward-line line-limit)
 323                (setq start (point)))
 324               (t                        ;0 => no limit (use with care!)
 325                (setq start (point-min))
 326                (setq search-limit (point-max))))))
 327     (while (and start
 328                 (< start search-limit)
 329                 (> ts-count 0))
 330       (setq start (time-stamp-once start search-limit ts-start ts-end
 331                                    ts-format format-lines end-lines))
 332       (setq ts-count (1- ts-count))))
 333   nil)
 334
 335 (defun time-stamp-once (start search-limit ts-start ts-end
 336                         ts-format format-lines end-lines)
 337   "Update one time stamp.  Internal routine called by \\[time-stamp].
 338 Returns the end point, which is where `time-stamp' begins the next search."
 339   (let ((case-fold-search nil)
 340         (end nil)
 341         end-search-start
 342         (end-length nil))
 343     (save-excursion
 344       (save-restriction
 345         (widen)
 346         ;; Find the location of the time stamp.
 347         (while (and (< (goto-char start) search-limit)
 348                     (not end)
 349                     (re-search-forward ts-start search-limit 'move))
 350           (setq start (point))
 351           (if (not time-stamp-inserts-lines)
 352               (forward-line format-lines))
 353           (setq end-search-start (max start (point)))
 354           (if (= (forward-line end-lines) 0)
 355               (progn
 356                (and (bolp) (backward-char))
 357                (let ((line-end (min (point) search-limit)))
 358                  (if (>= line-end end-search-start)
 359                      (progn
 360                       (goto-char end-search-start)
 361                       (if (re-search-forward ts-end line-end t)
 362                           (progn
 363                             (setq end (match-beginning 0))
 364                             (setq end-length (- (match-end 0) end))))))))))))
 365     (if end
 366         (progn
 367           ;; do all warnings outside save-excursion
 368           (cond
 369            ((not time-stamp-active)
 370             (if time-stamp-warn-inactive
 371                 ;; don't signal an error in a write-file-hook
 372                 (progn
 373                   (message "Warning: time-stamp-active is off; did not time-stamp buffer.")
 374                   (sit-for 1))))
 375            ((not (and (stringp ts-start)
 376                       (stringp ts-end)))
 377             (message "time-stamp-start or time-stamp-end is not a string")
 378             (sit-for 1))
 379            (t
 380             (let ((new-time-stamp (time-stamp-string ts-format)))
 381               (if (and (stringp new-time-stamp)
 382                        (not (string-equal (buffer-substring start end)
 383                                           new-time-stamp)))
 384                   (save-excursion
 385                     (save-restriction
 386                       (widen)
 387                       (delete-region start end)
 388                       (goto-char start)
 389                       (insert-and-inherit new-time-stamp)
 390                       (setq end (point))
 391                       ;; remove any tabs used to format time stamp
 392                       (if (search-backward "\t" start t)
 393                           (progn
 394                             (untabify start end)
 395                             (setq end (point))))))))))))
 396     ;; return the location after this time stamp, if there was one
 397     (and end end-length
 398          (+ end end-length))))
 399
 400
 401 ;;;###autoload
 402 (defun time-stamp-toggle-active (&optional arg)
 403   "Toggle `time-stamp-active', setting whether \\[time-stamp] updates a buffer.
 404 With ARG, turn time stamping on if and only if arg is positive."
 405   (interactive "P")
 406   (setq time-stamp-active
 407         (if (null arg)
 408             (not time-stamp-active)
 409           (> (prefix-numeric-value arg) 0)))
 410   (message "time-stamp is now %s." (if time-stamp-active "active" "off")))
 411
 412
 413 (defun time-stamp-string (&optional ts-format)
 414   "Generate the new string to be inserted by \\[time-stamp].
 415 Optionally use format TS-FORMAT instead of `time-stamp-format' to
 416 format the string."
 417   (or ts-format
 418       (setq ts-format time-stamp-format))
 419   (if (stringp ts-format)
 420       (if (stringp time-stamp-time-zone)
 421           (let ((ts-real-time-zone (getenv "TZ")))
 422             (unwind-protect
 423                 (progn
 424                   (set-time-zone-rule time-stamp-time-zone)
 425                   (format-time-string
 426                    (time-stamp-string-preprocess ts-format)))
 427               (set-time-zone-rule ts-real-time-zone)))
 428         (format-time-string
 429          (time-stamp-string-preprocess ts-format)))
 430     ;; handle version 1 compatibility
 431     (cond ((or (eq time-stamp-old-format-warn 'error)
 432                (and (eq time-stamp-old-format-warn 'ask)
 433                     (not (y-or-n-p "Use non-string time-stamp-format? "))))
 434            (message "Warning: no time-stamp: time-stamp-format not a string")
 435            (sit-for 1)
 436            nil)
 437           (t
 438            (cond ((eq time-stamp-old-format-warn 'warn)
 439                   (message "Obsolescent time-stamp-format type; should be string")
 440                   (sit-for 1)))
 441            (time-stamp-fconcat ts-format " ")))))
 442
 443 (defconst time-stamp-no-file "(no file)"
 444   "String to use when the buffer is not associated with a file.")
 445
 446 ;;; time-stamp is transitioning to using the new, expanded capabilities
 447 ;;; of format-time-string.  During the process, this function implements
 448 ;;; intermediate, compatible formats and complains about old, soon to
 449 ;;; be unsupported, formats.  This function will get a lot (a LOT) shorter
 450 ;;; when the transition is complete and we can just pass most things
 451 ;;; straight through to format-time-string.
 452 ;;;      At all times, all the formats recommended in the doc string
 453 ;;; of time-stamp-format will work not only in the current version of
 454 ;;; Emacs, but in all versions that have been released within the past
 455 ;;; two years.
 456 ;;;      The : modifier is a temporary conversion feature used to resolve
 457 ;;; ambiguous formats--formats that are changing (over time) incompatibly.
 458 (defun time-stamp-string-preprocess (format &optional time)
 459   "Use a FORMAT to format date, time, file, and user information.
 460 Optional second argument TIME is only for testing.
 461 Implements non-time extensions to `format-time-string'
 462 and all `time-stamp-format' compatibility."
 463   (let ((fmt-len (length format))
 464         (ind 0)
 465         cur-char
 466         (prev-char nil)
 467         (result "")
 468         field-width
 469         field-result
 470         alt-form change-case require-padding
 471         (paren-level 0))
 472     (while (< ind fmt-len)
 473       (setq cur-char (aref format ind))
 474       (setq
 475        result
 476        (concat result
 477       (cond
 478        ((eq cur-char ?%)
 479         ;; eat any additional args to allow for future expansion
 480         (setq alt-form nil change-case nil require-padding nil field-width "")
 481         (while (progn
 482                  (setq ind (1+ ind))
 483                  (setq cur-char (if (< ind fmt-len)
 484                                     (aref format ind)
 485                                   ?\0))
 486                  (or (eq ?. cur-char)
 487                      (eq ?, cur-char) (eq ?: cur-char) (eq ?@ cur-char)
 488                      (eq ?- cur-char) (eq ?+ cur-char) (eq ?_ cur-char)
 489                      (eq ?\  cur-char) (eq ?# cur-char) (eq ?^ cur-char)
 490                      (and (eq ?\( cur-char)
 491                           (not (eq prev-char ?\\))
 492                           (setq paren-level (1+ paren-level)))
 493                      (if (and (eq ?\) cur-char)
 494                               (not (eq prev-char ?\\))
 495                               (> paren-level 0))
 496                          (setq paren-level (1- paren-level))
 497                        (and (> paren-level 0)
 498                             (< ind fmt-len)))
 499                      (if (and (<= ?0 cur-char) (>= ?9 cur-char))
 500                          ;; get format width
 501                          (let ((field-index ind))
 502                            (while (progn
 503                                     (setq ind (1+ ind))
 504                                     (setq cur-char (if (< ind fmt-len)
 505                                                        (aref format ind)
 506                                                      ?\0))
 507                                     (and (<= ?0 cur-char) (>= ?9 cur-char))))
 508                            (setq field-width (substring format field-index ind))
 509                            (setq ind (1- ind))
 510                            t))))
 511           (setq prev-char cur-char)
 512           ;; some characters we actually use
 513           (cond ((eq cur-char ?:)
 514                  (setq alt-form t))
 515                 ((eq cur-char ?#)
 516                  (setq change-case t))))
 517         (setq field-result
 518         (cond
 519          ((eq cur-char ?%)
 520           "%%")
 521          ((eq cur-char ?a)              ;day of week
 522           (if change-case
 523               (format-time-string "%#a" time)
 524             (or alt-form (not (string-equal field-width ""))
 525                 (time-stamp-conv-warn "%a" "%:a"))
 526             (if (and alt-form (not (string-equal field-width "")))
 527                 ""                      ;discourage "%:3a"
 528               (format-time-string "%A" time))))
 529          ((eq cur-char ?A)
 530           (if alt-form
 531               (format-time-string "%A" time)
 532             (or change-case (not (string-equal field-width ""))
 533                 (time-stamp-conv-warn "%A" "%#A"))
 534             (format-time-string "%#A" time)))
 535          ((eq cur-char ?b)              ;month name
 536           (if change-case
 537               (format-time-string "%#b" time)
 538             (or alt-form (not (string-equal field-width ""))
 539                 (time-stamp-conv-warn "%b" "%:b"))
 540             (if (and alt-form (not (string-equal field-width "")))
 541                 ""                      ;discourage "%:3b"
 542             (format-time-string "%B" time))))
 543          ((eq cur-char ?B)
 544           (if alt-form
 545               (format-time-string "%B" time)
 546             (or change-case (not (string-equal field-width ""))
 547                 (time-stamp-conv-warn "%B" "%#B"))
 548             (format-time-string "%#B" time)))
 549          ((eq cur-char ?d)              ;day of month, 1-31
 550           (time-stamp-do-number cur-char alt-form field-width time))
 551          ((eq cur-char ?H)              ;hour, 0-23
 552           (time-stamp-do-number cur-char alt-form field-width time))
 553          ((eq cur-char ?I)              ;hour, 1-12
 554           (time-stamp-do-number cur-char alt-form field-width time))
 555          ((eq cur-char ?m)              ;month number, 1-12
 556           (time-stamp-do-number cur-char alt-form field-width time))
 557          ((eq cur-char ?M)              ;minute, 0-59
 558           (time-stamp-do-number cur-char alt-form field-width time))
 559          ((eq cur-char ?p)              ;am or pm
 560           (or change-case
 561               (time-stamp-conv-warn "%p" "%#p"))
 562           (format-time-string "%#p" time))
 563          ((eq cur-char ?P)              ;AM or PM
 564           (format-time-string "%p" time))
 565          ((eq cur-char ?S)              ;seconds, 00-60
 566           (time-stamp-do-number cur-char alt-form field-width time))
 567          ((eq cur-char ?w)              ;weekday number, Sunday is 0
 568           (format-time-string "%w" time))
 569          ((eq cur-char ?y)              ;year
 570           (or alt-form (not (string-equal field-width ""))
 571               (time-stamp-conv-warn "%y" "%:y"))
 572           (string-to-number (format-time-string "%Y" time)))
 573          ((eq cur-char ?Y)              ;4-digit year, new style
 574           (string-to-number (format-time-string "%Y" time)))
 575          ((eq cur-char ?z)              ;time zone lower case
 576           (if change-case
 577               ""                        ;discourage %z variations
 578             (format-time-string "%#Z" time)))
 579          ((eq cur-char ?Z)
 580           (if change-case
 581               (format-time-string "%#Z" time)
 582             (format-time-string "%Z" time)))
 583          ((eq cur-char ?f)              ;buffer-file-name, base name only
 584           (if buffer-file-name
 585               (file-name-nondirectory buffer-file-name)
 586             time-stamp-no-file))
 587          ((eq cur-char ?F)              ;buffer-file-name, full path
 588           (or buffer-file-name
 589               time-stamp-no-file))
 590          ((eq cur-char ?s)              ;system name
 591           (system-name))
 592          ((eq cur-char ?u)              ;user name
 593           (user-login-name))
 594          ((eq cur-char ?U)              ;user full name
 595           (user-full-name))
 596          ((eq cur-char ?l)              ;logname (undocumented user name alt)
 597           (user-login-name))
 598          ((eq cur-char ?L)              ;(undocumented alt user full name)
 599           (user-full-name))
 600          ((eq cur-char ?h)              ;mail host name
 601           (time-stamp-mail-host-name))
 602          ((eq cur-char ?q)              ;(undocumented unqual hostname)
 603           (let ((qualname (system-name)))
 604             (if (string-match "\\." qualname)
 605                 (substring qualname 0 (match-beginning 0))
 606               qualname)))
 607          ((eq cur-char ?Q)              ;(undocumented fully-qualified host)
 608           (system-name))
 609          ))
 610         (let ((padded-result
 611                (format (format "%%%s%c"
 612                                field-width
 613                                (if (numberp field-result) ?d ?s))
 614                        (or field-result ""))))
 615           (let* ((initial-length (length padded-result))
 616                  (desired-length (if (string-equal field-width "")
 617                                      initial-length
 618                                    (string-to-number field-width))))
 619             (if (> initial-length desired-length)
 620                 ;; truncate strings on right, years on left
 621                 (if (stringp field-result)
 622                     (substring padded-result 0 desired-length)
 623                   (if (eq cur-char ?y)
 624                       (substring padded-result (- desired-length))
 625                     padded-result))     ;non-year numbers don't truncate
 626               padded-result))))
 627        (t
 628         (char-to-string cur-char)))))
 629       (setq ind (1+ ind)))
 630     result))
 631
 632 (defun time-stamp-do-number (format-char alt-form field-width time)
 633   "Handle compatible FORMAT-CHAR where only default width/padding will change.
 634 ALT-FORM is whether `#' specified.  FIELD-WIDTH is the string
 635 width specification or \"\".  TIME is the time to convert."
 636   (let ((format-string (concat "%" (char-to-string format-char))))
 637     (and (not alt-form) (string-equal field-width "")
 638          (time-stamp-conv-warn format-string
 639                                (format "%%:%c" format-char)))
 640     (if (and alt-form (not (string-equal field-width "")))
 641         ""                              ;discourage "%:2d" and the like
 642       (string-to-number (format-time-string format-string time)))))
 643
 644 (defvar time-stamp-conversion-warn t
 645   "Warn about soon-to-be-unsupported forms in `time-stamp-format'.
 646 If nil, these warnings are disabled, which would be a bad idea!
 647 You really need to update your files instead.
 648
 649 The new formats will work with old versions of Emacs.
 650 New formats are being recommended now to allow `time-stamp-format'
 651 to change in the future to be compatible with `format-time-string'.
 652 The new forms being recommended now will continue to work then.")
 653
 654
 655 (defun time-stamp-conv-warn (old-form new-form)
 656   "Display a warning about a soon-to-be-obsolete format.
 657 Suggests replacing OLD-FORM with NEW-FORM."
 658   (cond
 659    (time-stamp-conversion-warn
 660     (save-excursion
 661       (set-buffer (get-buffer-create "*Time-stamp-compatibility*"))
 662       (goto-char (point-max))
 663       (if (bobp)
 664           (progn
 665             (insert
 666              "The formats recognized in time-stamp-format will change in a future release\n"
 667              "to be compatible with the new, expanded format-time-string function.\n\n"
 668              "The following obsolescent time-stamp-format construct(s) were found:\n\n")))
 669       (insert "\"" old-form "\" -- use " new-form "\n"))
 670     (display-buffer "*Time-stamp-compatibility*"))))
 671
 672
 673
 674 (defun time-stamp-mail-host-name ()
 675   "Return the name of the host where the user receives mail.
 676 This is the value of `mail-host-address' if bound and a string,
 677 otherwise the value of the function `system-name'."
 678   (or (and (boundp 'mail-host-address)
 679            (stringp mail-host-address)
 680            mail-host-address)
 681       (system-name)))
 682
 683 ;;; the rest of this file is for version 1 compatibility
 684
 685 (defun time-stamp-fconcat (list sep)
 686   "Similar to (mapconcat 'funcall LIST SEP) but LIST allows literals.
 687 If an element of LIST is a symbol, it is funcalled to get the string to use;
 688 the separator SEP is used between two strings obtained by funcalling a
 689 symbol.  Otherwise the element itself is inserted; no separator is used
 690 around literals."
 691   (let ((return-string "")
 692         (insert-sep-p nil))
 693     (while list
 694       (cond ((symbolp (car list))
 695              (if insert-sep-p
 696                  (setq return-string (concat return-string sep)))
 697              (setq return-string (concat return-string (funcall (car list))))
 698              (setq insert-sep-p t))
 699             (t
 700              (setq return-string (concat return-string (car list)))
 701              (setq insert-sep-p nil)))
 702       (setq list (cdr list)))
 703     return-string))
 704
 705 ;;; Some functions used in time-stamp-format
 706
 707 ;;; These functions have been obsolete since 1995
 708 ;;; and will be removed in Emacs 22.
 709 ;;; Meanwhile, discourage other packages from using them.
 710 (let ((obsolete-functions '(time-stamp-month-dd-yyyy
 711                             time-stamp-dd/mm/yyyy
 712                             time-stamp-mon-dd-yyyy
 713                             time-stamp-dd-mon-yy
 714                             time-stamp-yy/mm/dd
 715                             time-stamp-yyyy/mm/dd
 716                             time-stamp-yyyy-mm-dd
 717                             time-stamp-yymmdd
 718                             time-stamp-hh:mm:ss
 719                             time-stamp-hhmm)))
 720   (while obsolete-functions
 721     (make-obsolete (car obsolete-functions)
 722                    "use time-stamp-string or format-time-string instead."
 723                    "20.1")
 724     (setq obsolete-functions (cdr obsolete-functions))))
 725
 726 ;;; pretty form, suitable for a title page
 727
 728 (defun time-stamp-month-dd-yyyy ()
 729   "Return the current date as a string in \"Month DD, YYYY\" form."
 730   (format-time-string "%B %e, %Y"))
 731
 732 (defun time-stamp-dd/mm/yyyy ()
 733   "Return the current date as a string in \"DD/MM/YYYY\" form."
 734   (format-time-string "%d/%m/%Y"))
 735
 736 ;;; same as __DATE__ in ANSI C
 737
 738 (defun time-stamp-mon-dd-yyyy ()
 739   "Return the current date as a string in \"Mon DD YYYY\" form.
 740 The first character of DD is space if the value is less than 10."
 741   (format-time-string "%b %d %Y"))
 742
 743 ;;; RFC 822 date
 744
 745 (defun time-stamp-dd-mon-yy ()
 746   "Return the current date as a string in \"DD Mon YY\" form."
 747   (format-time-string "%d %b %y"))
 748
 749 ;;; RCS 3 date
 750
 751 (defun time-stamp-yy/mm/dd ()
 752   "Return the current date as a string in \"YY/MM/DD\" form."
 753   (format-time-string "%y/%m/%d"))
 754
 755 ;;; RCS 5 date
 756
 757 (defun time-stamp-yyyy/mm/dd ()
 758   "Return the current date as a string in \"YYYY/MM/DD\" form."
 759   (format-time-string "%Y/%m/%d"))
 760
 761 ;;; ISO 8601 date
 762
 763 (defun time-stamp-yyyy-mm-dd ()
 764   "Return the current date as a string in \"YYYY-MM-DD\" form."
 765   (format-time-string "%Y-%m-%d"))
 766
 767 (defun time-stamp-yymmdd ()
 768   "Return the current date as a string in \"YYMMDD\" form."
 769   (format-time-string "%y%m%d"))
 770
 771 (defun time-stamp-hh:mm:ss ()
 772   "Return the current time as a string in \"HH:MM:SS\" form."
 773   (format-time-string "%T"))
 774
 775 (defun time-stamp-hhmm ()
 776   "Return the current time as a string in \"HHMM\" form."
 777   (format-time-string "%H%M"))
 778
 779 (provide 'time-stamp)
 780
 781 ;;; arch-tag: 8a12c5c3-25d6-4a71-adc5-24b0e025a1e7
 782 ;;; time-stamp.el ends here