lisp/time-stamp.el

   1 ;;; time-stamp.el --- Maintain last change time stamps in files edited by Emacs
   2
   3 ;; Copyright (C) 1989, 1993-1995, 1997, 2000-2014 Free Software
   4 ;; 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 3 of the License, or
  15 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  24
  25 ;;; Commentary:
  26
  27 ;; A template in a file can be updated with a new time stamp when
  28 ;; you save the file.  For example:
  29 ;;     static char *ts = "sdmain.c Time-stamp: <2001-08-13 10:20:51 gildea>";
  30 ;; See the top of `time-stamp.el' for another example.
  31
  32 ;; To use time-stamping, add this line to your init file:
  33 ;;     (add-hook 'before-save-hook 'time-stamp)
  34 ;; Now any time-stamp templates in your files will be updated automatically.
  35
  36 ;; See the documentation for the functions `time-stamp'
  37 ;; and `time-stamp-toggle-active' for details.
  38
  39 ;;; Code:
  40
  41 (defgroup time-stamp nil
  42   "Maintain last change time stamps in files edited by Emacs."
  43   :group 'data
  44   :group 'extensions)
  45
  46 (defcustom time-stamp-format "%:y-%02m-%02d %02H:%02M:%02S %u"
  47   "Format of the string inserted by \\[time-stamp].
  48 The value may be a string or a list.  Lists are supported only for
  49 backward compatibility; see variable `time-stamp-old-format-warn'.
  50
  51 A string is used verbatim except for character sequences beginning
  52 with %, as follows.  The values of non-numeric formatted items depend
  53 on the locale setting recorded in `system-time-locale' and
  54 `locale-coding-system'.  The examples here are for the default
  55 \(`C') locale.
  56
  57 %:a  weekday name: `Monday'.            %#A gives uppercase: `MONDAY'
  58 %3a  abbreviated weekday: `Mon'.        %3A gives uppercase: `MON'
  59 %:b  month name: `January'.             %#B gives uppercase: `JANUARY'
  60 %3b  abbreviated month: `Jan'.          %3B gives uppercase: `JAN'
  61 %02d day of month
  62 %02H 24-hour clock hour
  63 %02I 12-hour clock hour
  64 %02m month number
  65 %02M minute
  66 %#p  `am' or `pm'.                      %P  gives uppercase: `AM' or `PM'
  67 %02S seconds
  68 %w   day number of week, Sunday is 0
  69 %02y 2-digit year: `03'                 %:y 4-digit year: `2003'
  70 %z   time zone name: `est'.             %Z  gives uppercase: `EST'
  71
  72 Non-date items:
  73 %%   a literal percent character: `%'
  74 %f   file name without directory        %F  gives absolute pathname
  75 %s   system name
  76 %u   user's login name                  %U  user's full name
  77 %h   mail host name
  78
  79 Decimal digits between the % and the type character specify the
  80 field width.  Strings are truncated on the right; years on the left.
  81 A leading zero in the field width zero-fills a number.
  82
  83 For example, to get the format used by the `date' command,
  84 use \"%3a %3b %2d %02H:%02M:%02S %Z %:y\".
  85
  86 In the future these formats will be aligned more with `format-time-string'.
  87 Because of this transition, the default padding for numeric formats will
  88 change in a future version.  Therefore either a padding width should be
  89 specified, or the : modifier should be used to explicitly request the
  90 historical default."
  91   :type 'string
  92   :group 'time-stamp
  93   :version "20.1")
  94 ;;;###autoload(put 'time-stamp-format 'safe-local-variable 'stringp)
  95
  96 (defcustom time-stamp-active t
  97   "Non-nil to enable time-stamping of buffers by \\[time-stamp].
  98 Can be toggled by \\[time-stamp-toggle-active].
  99 See also the variable `time-stamp-warn-inactive'."
 100   :type 'boolean
 101   :group 'time-stamp)
 102
 103 (defcustom time-stamp-warn-inactive t
 104   "Have \\[time-stamp] warn if a buffer did not get time-stamped.
 105 If non-nil, a warning is displayed if `time-stamp-active' has
 106 deactivated time stamping and the buffer contains a template that
 107 otherwise would have been updated."
 108   :type 'boolean
 109   :group 'time-stamp
 110   :version "19.29")
 111
 112 (defcustom time-stamp-old-format-warn 'ask
 113   "Action if `time-stamp-format' is an old-style list.
 114 If `error', the format is not used.  If `ask', the user is queried about
 115 using the time-stamp-format.  If `warn', a warning is displayed.
 116 If nil, no notification is given."
 117   :type '(choice (const :tag "Don't use the format" error)
 118                  (const ask)
 119                  (const warn)
 120                  (const :tag "No notification" nil))
 121   :group 'time-stamp)
 122
 123 (defcustom time-stamp-time-zone nil
 124   "If non-nil, a string naming the timezone to be used by \\[time-stamp].
 125 Format is the same as that used by the environment variable TZ on your system."
 126   :type '(choice (const nil) string)
 127   :group 'time-stamp
 128   :version "20.1")
 129 ;;;###autoload(put 'time-stamp-time-zone 'safe-local-variable 'string-or-null-p)
 130
 131 ;;; Do not change time-stamp-line-limit, time-stamp-start,
 132 ;;; time-stamp-end, time-stamp-pattern, time-stamp-inserts-lines,
 133 ;;; or time-stamp-count in your .emacs or you will be incompatible
 134 ;;; with other people's files!  If you must change them, do so only
 135 ;;; in the local variables section of the file itself.
 136
 137
 138 (defvar time-stamp-line-limit 8     ;Do not change!
 139   "Lines of a file searched; positive counts from start, negative from end.
 140 The patterns `time-stamp-start' and `time-stamp-end' must be found in
 141 the first (last) `time-stamp-line-limit' lines of the file for the
 142 file to be time-stamped by \\[time-stamp].  A value of 0 searches the
 143 entire buffer (use with care).
 144
 145 This value can also be set with the variable `time-stamp-pattern'.
 146
 147 Do not change `time-stamp-line-limit', `time-stamp-start',
 148 `time-stamp-end', or `time-stamp-pattern' for yourself or you will be
 149 incompatible with other people's files!  If you must change them for some
 150 application, do so in the local variables section of the time-stamped file
 151 itself.")
 152 ;;;###autoload(put 'time-stamp-line-limit 'safe-local-variable 'integerp)
 153
 154 (defvar time-stamp-start "Time-stamp:[ \t]+\\\\?[\"<]+"    ;Do not change!
 155   "Regexp after which the time stamp is written by \\[time-stamp].
 156 See also the variables `time-stamp-end' and `time-stamp-line-limit'.
 157
 158 This value can also be set with the variable `time-stamp-pattern'.
 159
 160 Do not change `time-stamp-line-limit', `time-stamp-start',
 161 `time-stamp-end', or `time-stamp-pattern' for yourself or you will be
 162 incompatible with other people's files!  If you must change them for some
 163 application, do so in the local variables section of the time-stamped file
 164 itself.")
 165 ;;;###autoload(put 'time-stamp-start 'safe-local-variable 'stringp)
 166
 167 (defvar time-stamp-end "\\\\?[\">]"    ;Do not change!
 168   "Regexp marking the text after the time stamp.
 169 \\[time-stamp] deletes the text between the first match of `time-stamp-start'
 170 and the following match of `time-stamp-end', then writes the
 171 time stamp specified by `time-stamp-format' between them.
 172
 173 This value can also be set with the variable `time-stamp-pattern'.
 174
 175 The end text normally starts on the same line as the start text ends,
 176 but if there are any newlines in `time-stamp-format', the same number
 177 of newlines must separate the start and end.  \\[time-stamp] tries
 178 to not change the number of lines in the buffer.  `time-stamp-inserts-lines'
 179 controls this behavior.
 180
 181 Do not change `time-stamp-start', `time-stamp-end', `time-stamp-pattern',
 182 or `time-stamp-inserts-lines' for yourself or you will be incompatible
 183 with other people's files!  If you must change them for some application,
 184 do so in the local variables section of the time-stamped file itself.")
 185 ;;;###autoload(put 'time-stamp-end 'safe-local-variable 'stringp)
 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 ;;;###autoload(put 'time-stamp-inserts-lines 'safe-local-variable 'symbolp)
 203
 204
 205 (defvar time-stamp-count 1              ;Do not change!
 206   "How many templates \\[time-stamp] will look for in a buffer.
 207 The same time stamp will be written in each case.
 208
 209 Do not change `time-stamp-count' for yourself or you will be
 210 incompatible with other people's files!  If you must change it for
 211 some application, do so in the local variables section of the
 212 time-stamped file itself.")
 213 ;;;###autoload(put 'time-stamp-count 'safe-local-variable 'integerp)
 214
 215
 216 (defvar time-stamp-pattern nil          ;Do not change!
 217   "Convenience variable setting all `time-stamp' location and format values.
 218 This string has four parts, each of which is optional.
 219 These four parts set `time-stamp-line-limit', `time-stamp-start',
 220 `time-stamp-format', and `time-stamp-end'.  See the documentation
 221 for each of these variables for details.
 222
 223 The first part is a number followed by a slash; the number sets the number
 224 of lines at the beginning (negative counts from end) of the file searched
 225 for the time stamp.  The number and the slash may be omitted to use the
 226 normal value.
 227
 228 The second part is a regexp identifying the pattern preceding the time stamp.
 229 This part may be omitted to use the normal pattern.
 230
 231 The third part specifies the format of the time stamp inserted.  See
 232 the documentation for `time-stamp-format' for details.  Specify this
 233 part as \"%%\" to use the normal format.
 234
 235 The fourth part is a regexp identifying the pattern following the time stamp.
 236 This part may be omitted to use the normal pattern.
 237
 238 Examples:
 239 \"-10/\"
 240 \"-9/^Last modified: %%$\"
 241 \"@set Time-stamp: %:b %:d, %:y$\"
 242 \"newcommand{\\\\\\\\timestamp}{%%}\"
 243
 244 Do not change `time-stamp-pattern' `time-stamp-line-limit',
 245 `time-stamp-start', or `time-stamp-end' for yourself or you will be
 246 incompatible with other people's files!  If you must change them for
 247 some application, do so only in the local variables section of the
 248 time-stamped file itself.")
 249 ;;;###autoload(put 'time-stamp-pattern 'safe-local-variable 'stringp)
 250
 251
 252
 253 ;;;###autoload
 254 (defun time-stamp ()
 255   "Update the time stamp string(s) in the buffer.
 256 A template in a file can be automatically updated with a new time stamp
 257 every time you save the file.  Add this line to your init file:
 258     (add-hook 'before-save-hook 'time-stamp)
 259 or customize `before-save-hook' through Custom.
 260 Normally the template must appear in the first 8 lines of a file and
 261 look like one of the following:
 262       Time-stamp: <>
 263       Time-stamp: \" \"
 264 The time stamp is written between the brackets or quotes:
 265       Time-stamp: <2001-02-18 10:20:51 gildea>
 266 The time stamp is updated only if the variable `time-stamp-active' is non-nil.
 267 The format of the time stamp is set by the variable `time-stamp-pattern' or
 268 `time-stamp-format'.  The variables `time-stamp-pattern',
 269 `time-stamp-line-limit', `time-stamp-start', `time-stamp-end',
 270 `time-stamp-count', and `time-stamp-inserts-lines' control finding
 271 the template."
 272   (interactive)
 273   (let ((line-limit time-stamp-line-limit)
 274         (ts-start time-stamp-start)
 275         (ts-format time-stamp-format)
 276         (ts-end time-stamp-end)
 277         (ts-count time-stamp-count)
 278         (format-lines 0)
 279         (end-lines 1)
 280         (start nil)
 281         search-limit)
 282     (if (stringp time-stamp-pattern)
 283         (progn
 284           (string-match "\\`\\(\\(-?[0-9]+\\)/\\)?\\([^%]+\\)?\\(\\(%[-.,:@+_ #^()0-9]*[A-Za-z%][^%]*\\)*%[-.,:@+_ #^()0-9]*[A-Za-z%]\\)?\\([^%]+\\)?\\'" time-stamp-pattern)
 285           (and (match-beginning 2)
 286                (setq line-limit
 287                      (string-to-number (match-string 2 time-stamp-pattern))))
 288           (and (match-beginning 3)
 289                (setq ts-start (match-string 3 time-stamp-pattern)))
 290           (and (match-beginning 4)
 291                (not (string-equal (match-string 4 time-stamp-pattern) "%%"))
 292                (setq ts-format (match-string 4 time-stamp-pattern)))
 293           (and (match-beginning 6)
 294                (setq ts-end (match-string 6 time-stamp-pattern)))))
 295     (cond ((not (integerp line-limit))
 296            (setq line-limit 8)
 297            (message "time-stamp-line-limit is not an integer")
 298            (sit-for 1)))
 299     (cond ((not (integerp ts-count))
 300            (setq ts-count 1)
 301            (message "time-stamp-count is not an integer")
 302            (sit-for 1))
 303           ((< ts-count 1)
 304            ;; We need to call time-stamp-once at least once
 305            ;; to output any warnings about time-stamp not being active.
 306            (setq ts-count 1)))
 307     ;; Figure out what lines the end should be on.
 308     (if (stringp ts-format)
 309         (let ((nl-start 0))
 310           (while (string-match "\n" ts-format nl-start)
 311             (setq format-lines (1+ format-lines) nl-start (match-end 0)))))
 312     (let ((nl-start 0))
 313       (while (string-match "\n" ts-end nl-start)
 314         (setq end-lines (1+ end-lines) nl-start (match-end 0))))
 315     ;; Find overall what lines to look at
 316     (save-excursion
 317       (save-restriction
 318         (widen)
 319         (cond ((> line-limit 0)
 320                (goto-char (setq start (point-min)))
 321                (forward-line line-limit)
 322                (setq search-limit (point)))
 323               ((< line-limit 0)
 324                (goto-char (setq search-limit (point-max)))
 325                (forward-line line-limit)
 326                (setq start (point)))
 327               (t                        ;0 => no limit (use with care!)
 328                (setq start (point-min))
 329                (setq search-limit (point-max))))))
 330     (while (and start
 331                 (< start search-limit)
 332                 (> ts-count 0))
 333       (setq start (time-stamp-once start search-limit ts-start ts-end
 334                                    ts-format format-lines end-lines))
 335       (setq ts-count (1- ts-count))))
 336   nil)
 337
 338 (defun time-stamp-once (start search-limit ts-start ts-end
 339                         ts-format format-lines end-lines)
 340   "Update one time stamp.  Internal routine called by \\[time-stamp].
 341 Returns the end point, which is where `time-stamp' begins the next search."
 342   (let ((case-fold-search nil)
 343         (end nil)
 344         end-search-start
 345         (end-length nil))
 346     (save-excursion
 347       (save-restriction
 348         (widen)
 349         ;; Find the location of the time stamp.
 350         (while (and (< (goto-char start) search-limit)
 351                     (not end)
 352                     (re-search-forward ts-start search-limit 'move))
 353           (setq start (point))
 354           (if (not time-stamp-inserts-lines)
 355               (forward-line format-lines))
 356           (setq end-search-start (max start (point)))
 357           (if (= (forward-line end-lines) 0)
 358               (progn
 359                (and (bolp) (backward-char))
 360                (let ((line-end (min (point) search-limit)))
 361                  (if (>= line-end end-search-start)
 362                      (progn
 363                       (goto-char end-search-start)
 364                       (if (re-search-forward ts-end line-end t)
 365                           (progn
 366                             (setq end (match-beginning 0))
 367                             (setq end-length (- (match-end 0) end))))))))))))
 368     (if end
 369         (progn
 370           ;; do all warnings outside save-excursion
 371           (cond
 372            ((not time-stamp-active)
 373             (if time-stamp-warn-inactive
 374                 ;; don't signal an error in a write-file-hook
 375                 (progn
 376                   (message "Warning: time-stamp-active is off; did not time-stamp buffer.")
 377                   (sit-for 1))))
 378            ((not (and (stringp ts-start)
 379                       (stringp ts-end)))
 380             (message "time-stamp-start or time-stamp-end is not a string")
 381             (sit-for 1))
 382            (t
 383             (let ((new-time-stamp (time-stamp-string ts-format)))
 384               (if (and (stringp new-time-stamp)
 385                        (not (string-equal (buffer-substring start end)
 386                                           new-time-stamp)))
 387                   (save-excursion
 388                     (save-restriction
 389                       (widen)
 390                       (delete-region start end)
 391                       (goto-char start)
 392                       (insert-and-inherit new-time-stamp)
 393                       (setq end (point))
 394                       ;; remove any tabs used to format time stamp
 395                       (if (search-backward "\t" start t)
 396                           (progn
 397                             (untabify start end)
 398                             (setq end (point))))))))))))
 399     ;; return the location after this time stamp, if there was one
 400     (and end end-length
 401          (+ end end-length))))
 402
 403
 404 ;;;###autoload
 405 (defun time-stamp-toggle-active (&optional arg)
 406   "Toggle `time-stamp-active', setting whether \\[time-stamp] updates a buffer.
 407 With ARG, turn time stamping on if and only if arg is positive."
 408   (interactive "P")
 409   (setq time-stamp-active
 410         (if (null arg)
 411             (not time-stamp-active)
 412           (> (prefix-numeric-value arg) 0)))
 413   (message "time-stamp is now %s." (if time-stamp-active "active" "off")))
 414
 415
 416 (defun time-stamp-string (&optional ts-format)
 417   "Generate the new string to be inserted by \\[time-stamp].
 418 Optionally use format TS-FORMAT instead of `time-stamp-format' to
 419 format the string."
 420   (or ts-format
 421       (setq ts-format time-stamp-format))
 422   (if (stringp ts-format)
 423       (if (stringp time-stamp-time-zone)
 424           (let ((ts-real-time-zone (getenv "TZ")))
 425             (unwind-protect
 426                 (progn
 427                   (setenv "TZ" time-stamp-time-zone)
 428                   (format-time-string
 429                    (time-stamp-string-preprocess ts-format)))
 430               (setenv "TZ" ts-real-time-zone)))
 431         (format-time-string
 432          (time-stamp-string-preprocess ts-format)))
 433     ;; handle version 1 compatibility
 434     (cond ((or (eq time-stamp-old-format-warn 'error)
 435                (and (eq time-stamp-old-format-warn 'ask)
 436                     (not (y-or-n-p "Use non-string time-stamp-format? "))))
 437            (message "Warning: no time-stamp: time-stamp-format not a string")
 438            (sit-for 1)
 439            nil)
 440           (t
 441            (cond ((eq time-stamp-old-format-warn 'warn)
 442                   (message "Obsolescent time-stamp-format type; should be string")
 443                   (sit-for 1)))
 444            (time-stamp-fconcat ts-format " ")))))
 445
 446 (defconst time-stamp-no-file "(no file)"
 447   "String to use when the buffer is not associated with a file.")
 448
 449 ;;; time-stamp is transitioning to using the new, expanded capabilities
 450 ;;; of format-time-string.  During the process, this function implements
 451 ;;; intermediate, compatible formats and complains about old, soon to
 452 ;;; be unsupported, formats.  This function will get a lot (a LOT) shorter
 453 ;;; when the transition is complete and we can just pass most things
 454 ;;; straight through to format-time-string.
 455 ;;;      At all times, all the formats recommended in the doc string
 456 ;;; of time-stamp-format will work not only in the current version of
 457 ;;; Emacs, but in all versions that have been released within the past
 458 ;;; two years.
 459 ;;;      The : modifier is a temporary conversion feature used to resolve
 460 ;;; ambiguous formats--formats that are changing (over time) incompatibly.
 461 (defun time-stamp-string-preprocess (format &optional time)
 462   "Use a FORMAT to format date, time, file, and user information.
 463 Optional second argument TIME is only for testing.
 464 Implements non-time extensions to `format-time-string'
 465 and all `time-stamp-format' compatibility."
 466   (let ((fmt-len (length format))
 467         (ind 0)
 468         cur-char
 469         (prev-char nil)
 470         (result "")
 471         field-width
 472         field-result
 473         alt-form change-case
 474         (paren-level 0))
 475     (while (< ind fmt-len)
 476       (setq cur-char (aref format ind))
 477       (setq
 478        result
 479        (concat result
 480       (cond
 481        ((eq cur-char ?%)
 482         ;; eat any additional args to allow for future expansion
 483         (setq alt-form nil change-case nil field-width "")
 484         (while (progn
 485                  (setq ind (1+ ind))
 486                  (setq cur-char (if (< ind fmt-len)
 487                                     (aref format ind)
 488                                   ?\0))
 489                  (or (eq ?. cur-char)
 490                      (eq ?, cur-char) (eq ?: cur-char) (eq ?@ cur-char)
 491                      (eq ?- cur-char) (eq ?+ cur-char) (eq ?_ cur-char)
 492                      (eq ?\s cur-char) (eq ?# cur-char) (eq ?^ cur-char)
 493                      (and (eq ?\( cur-char)
 494                           (not (eq prev-char ?\\))
 495                           (setq paren-level (1+ paren-level)))
 496                      (if (and (eq ?\) cur-char)
 497                               (not (eq prev-char ?\\))
 498                               (> paren-level 0))
 499                          (setq paren-level (1- paren-level))
 500                        (and (> paren-level 0)
 501                             (< ind fmt-len)))
 502                      (if (and (<= ?0 cur-char) (>= ?9 cur-char))
 503                          ;; get format width
 504                          (let ((field-index ind))
 505                            (while (progn
 506                                     (setq ind (1+ ind))
 507                                     (setq cur-char (if (< ind fmt-len)
 508                                                        (aref format ind)
 509                                                      ?\0))
 510                                     (and (<= ?0 cur-char) (>= ?9 cur-char))))
 511                            (setq field-width (substring format field-index ind))
 512                            (setq ind (1- ind))
 513                            t))))
 514           (setq prev-char cur-char)
 515           ;; some characters we actually use
 516           (cond ((eq cur-char ?:)
 517                  (setq alt-form t))
 518                 ((eq cur-char ?#)
 519                  (setq change-case t))))
 520         (setq field-result
 521         (cond
 522          ((eq cur-char ?%)
 523           "%%")
 524          ((eq cur-char ?a)              ;day of week
 525           (if change-case
 526               (format-time-string "%#a" time)
 527             (or alt-form (not (string-equal field-width ""))
 528                 (time-stamp-conv-warn "%a" "%:a"))
 529             (if (and alt-form (not (string-equal field-width "")))
 530                 ""                      ;discourage "%:3a"
 531               (format-time-string "%A" time))))
 532          ((eq cur-char ?A)
 533           (if alt-form
 534               (format-time-string "%A" time)
 535             (or change-case (not (string-equal field-width ""))
 536                 (time-stamp-conv-warn "%A" "%#A"))
 537             (format-time-string "%#A" time)))
 538          ((eq cur-char ?b)              ;month name
 539           (if change-case
 540               (format-time-string "%#b" time)
 541             (or alt-form (not (string-equal field-width ""))
 542                 (time-stamp-conv-warn "%b" "%:b"))
 543             (if (and alt-form (not (string-equal field-width "")))
 544                 ""                      ;discourage "%:3b"
 545             (format-time-string "%B" time))))
 546          ((eq cur-char ?B)
 547           (if alt-form
 548               (format-time-string "%B" time)
 549             (or change-case (not (string-equal field-width ""))
 550                 (time-stamp-conv-warn "%B" "%#B"))
 551             (format-time-string "%#B" time)))
 552          ((eq cur-char ?d)              ;day of month, 1-31
 553           (time-stamp-do-number cur-char alt-form field-width time))
 554          ((eq cur-char ?H)              ;hour, 0-23
 555           (time-stamp-do-number cur-char alt-form field-width time))
 556          ((eq cur-char ?I)              ;hour, 1-12
 557           (time-stamp-do-number cur-char alt-form field-width time))
 558          ((eq cur-char ?m)              ;month number, 1-12
 559           (time-stamp-do-number cur-char alt-form field-width time))
 560          ((eq cur-char ?M)              ;minute, 0-59
 561           (time-stamp-do-number cur-char alt-form field-width time))
 562          ((eq cur-char ?p)              ;am or pm
 563           (or change-case
 564               (time-stamp-conv-warn "%p" "%#p"))
 565           (format-time-string "%#p" time))
 566          ((eq cur-char ?P)              ;AM or PM
 567           (format-time-string "%p" time))
 568          ((eq cur-char ?S)              ;seconds, 00-60
 569           (time-stamp-do-number cur-char alt-form field-width time))
 570          ((eq cur-char ?w)              ;weekday number, Sunday is 0
 571           (format-time-string "%w" time))
 572          ((eq cur-char ?y)              ;year
 573           (or alt-form (not (string-equal field-width ""))
 574               (time-stamp-conv-warn "%y" "%:y"))
 575           (string-to-number (format-time-string "%Y" time)))
 576          ((eq cur-char ?Y)              ;4-digit year, new style
 577           (string-to-number (format-time-string "%Y" time)))
 578          ((eq cur-char ?z)              ;time zone lower case
 579           (if change-case
 580               ""                        ;discourage %z variations
 581             (format-time-string "%#Z" time)))
 582          ((eq cur-char ?Z)
 583           (if change-case
 584               (format-time-string "%#Z" time)
 585             (format-time-string "%Z" time)))
 586          ((eq cur-char ?f)              ;buffer-file-name, base name only
 587           (if buffer-file-name
 588               (file-name-nondirectory buffer-file-name)
 589             time-stamp-no-file))
 590          ((eq cur-char ?F)              ;buffer-file-name, full path
 591           (or buffer-file-name
 592               time-stamp-no-file))
 593          ((eq cur-char ?s)              ;system name
 594           (system-name))
 595          ((eq cur-char ?u)              ;user name
 596           (user-login-name))
 597          ((eq cur-char ?U)              ;user full name
 598           (user-full-name))
 599          ((eq cur-char ?l)              ;logname (undocumented user name alt)
 600           (user-login-name))
 601          ((eq cur-char ?L)              ;(undocumented alt user full name)
 602           (user-full-name))
 603          ((eq cur-char ?h)              ;mail host name
 604           (time-stamp-mail-host-name))
 605          ((eq cur-char ?q)              ;(undocumented unqual hostname)
 606           (let ((qualname (system-name)))
 607             (if (string-match "\\." qualname)
 608                 (substring qualname 0 (match-beginning 0))
 609               qualname)))
 610          ((eq cur-char ?Q)              ;(undocumented fully-qualified host)
 611           (system-name))
 612          ))
 613         (let ((padded-result
 614                (format (format "%%%s%c"
 615                                field-width
 616                                (if (numberp field-result) ?d ?s))
 617                        (or field-result ""))))
 618           (let* ((initial-length (length padded-result))
 619                  (desired-length (if (string-equal field-width "")
 620                                      initial-length
 621                                    (string-to-number field-width))))
 622             (if (> initial-length desired-length)
 623                 ;; truncate strings on right, years on left
 624                 (if (stringp field-result)
 625                     (substring padded-result 0 desired-length)
 626                   (if (eq cur-char ?y)
 627                       (substring padded-result (- desired-length))
 628                     padded-result))     ;non-year numbers don't truncate
 629               padded-result))))
 630        (t
 631         (char-to-string cur-char)))))
 632       (setq ind (1+ ind)))
 633     result))
 634
 635 (defun time-stamp-do-number (format-char alt-form field-width time)
 636   "Handle compatible FORMAT-CHAR where only default width/padding will change.
 637 ALT-FORM is whether `#' specified.  FIELD-WIDTH is the string
 638 width specification or \"\".  TIME is the time to convert."
 639   (let ((format-string (concat "%" (char-to-string format-char))))
 640     (and (not alt-form) (string-equal field-width "")
 641          (time-stamp-conv-warn format-string
 642                                (format "%%:%c" format-char)))
 643     (if (and alt-form (not (string-equal field-width "")))
 644         ""                              ;discourage "%:2d" and the like
 645       (string-to-number (format-time-string format-string time)))))
 646
 647 (defvar time-stamp-conversion-warn t
 648   "Warn about soon-to-be-unsupported forms in `time-stamp-format'.
 649 If nil, these warnings are disabled, which would be a bad idea!
 650 You really need to update your files instead.
 651
 652 The new formats will work with old versions of Emacs.
 653 New formats are being recommended now to allow `time-stamp-format'
 654 to change in the future to be compatible with `format-time-string'.
 655 The new forms being recommended now will continue to work then.")
 656
 657
 658 (defun time-stamp-conv-warn (old-form new-form)
 659   "Display a warning about a soon-to-be-obsolete format.
 660 Suggests replacing OLD-FORM with NEW-FORM."
 661   (cond
 662    (time-stamp-conversion-warn
 663     (with-current-buffer (get-buffer-create "*Time-stamp-compatibility*")
 664       (goto-char (point-max))
 665       (if (bobp)
 666           (progn
 667             (insert
 668              "The formats recognized in time-stamp-format will change in a future release\n"
 669              "to be compatible with the new, expanded format-time-string function.\n\n"
 670              "The following obsolescent time-stamp-format construct(s) were found:\n\n")))
 671       (insert "\"" old-form "\" -- use " new-form "\n"))
 672     (display-buffer "*Time-stamp-compatibility*"))))
 673
 674
 675
 676 (defun time-stamp-mail-host-name ()
 677   "Return the name of the host where the user receives mail.
 678 This is the value of `mail-host-address' if bound and a string,
 679 otherwise the value of the function `system-name'."
 680   (or (and (boundp 'mail-host-address)
 681            (stringp mail-host-address)
 682            mail-host-address)
 683       (system-name)))
 684
 685 ;;; the rest of this file is for version 1 compatibility
 686
 687 (defun time-stamp-fconcat (list sep)
 688   "Similar to (mapconcat 'funcall LIST SEP) but LIST allows literals.
 689 If an element of LIST is a symbol, it is funcalled to get the string to use;
 690 the separator SEP is used between two strings obtained by funcalling a
 691 symbol.  Otherwise the element itself is inserted; no separator is used
 692 around literals."
 693   (let ((return-string "")
 694         (insert-sep-p nil))
 695     (while list
 696       (cond ((symbolp (car list))
 697              (if insert-sep-p
 698                  (setq return-string (concat return-string sep)))
 699              (setq return-string (concat return-string (funcall (car list))))
 700              (setq insert-sep-p t))
 701             (t
 702              (setq return-string (concat return-string (car list)))
 703              (setq insert-sep-p nil)))
 704       (setq list (cdr list)))
 705     return-string))
 706
 707 (provide 'time-stamp)
 708
 709 ;;; time-stamp.el ends here